Clinical impact of EUS elastography followed by contrast-enhanced EUS in patients with focal pancreatic masses and negative EUS-guided FNA

DEFF Research Database (Denmark)

Iordache, Sevastiţa; Costache, Mădălin Ionuţ; Popescu, Carmen Florina

2016-01-01

and negative cytopathology after EUS-FNA, based on previously published results and cut-offs of real-time elastographic (RTE) EUS and contrast-enhanced harmonic (CEH) EUS. MATERIAL AND METHODS: We included in the study a subgroup of 50 consecutive patients with focal pancreatic masses which underwent EUS...... malignancy, the sensitivity, specificity and accuracy of RTE-EUS were: 97.7%, 77.4%, and 84% respectively. CEH-EUS had similar results: 89.5%, 80.7%, and 84%, respectively. In 25 patients with soft/mixed appearance during elastography,sequential assessment using contrast-enhanced EUSwas performed...

Novel Technique for Hepatic Fiducial Marker Placement for Stereotactic Body Radiation Therapy

International Nuclear Information System (INIS)

Jarraya, Hajer; Chalayer, Chloé; Tresch, Emmanuelle; Bonodeau, Francois; Lacornerie, Thomas; Mirabel, Xavier; Boulanger, Thomas; Taieb, Sophie; Kramar, Andrew; Lartigau, Eric; Ceugnart, Luc

2014-01-01

Purpose: To report experience with fiducial marker insertion and describe an advantageous, novel technique for fiducial placement in the liver for stereotactic body radiation therapy with respiratory tracking. Methods and Materials: We implanted 1444 fiducials (single: 834; linked: 610) in 328 patients with 424 hepatic lesions. Two methods of implantation were compared: the standard method (631 single fiducials) performed on 153 patients from May 2007 to May 2010, and the cube method (813 fiducials: 610 linked/203 single) applied to 175 patients from April 2010 to March 2013. The standard method involved implanting a single marker at a time. The novel technique entailed implanting 2 pairs of linked markers when possible in a way to occupy the perpendicular edges of a cube containing the tumor inside. Results: Mean duration of the cube method was shorter than the standard method (46 vs 61 minutes; P<.0001). Median numbers of skin and subcapsular entries were significantly smaller with the cube method (2 vs 4, P<.0001, and 2 vs 4, P<.0001, respectively). The rate of overall complications (total, major, and minor) was significantly lower in the cube method group compared with the standard method group (5.7% vs 13.7%; P=.013). Major complications occurred while using single markers only. The success rate was 98.9% for the cube method and 99.3% for the standard method. Conclusions: We propose a new technique of hepatic fiducial implantation that makes use of linked fiducials and involves fewer skin entries and shorter time of implantation. The technique is less complication-prone and is migration-resistant

Full automatic fiducial marker detection on coil arrays for accurate instrumentation placement during MRI guided breast interventions

Science.gov (United States)

Filippatos, Konstantinos; Boehler, Tobias; Geisler, Benjamin; Zachmann, Harald; Twellmann, Thorsten

2010-02-01

With its high sensitivity, dynamic contrast-enhanced MR imaging (DCE-MRI) of the breast is today one of the first-line tools for early detection and diagnosis of breast cancer, particularly in the dense breast of young women. However, many relevant findings are very small or occult on targeted ultrasound images or mammography, so that MRI guided biopsy is the only option for a precise histological work-up [1]. State-of-the-art software tools for computer-aided diagnosis of breast cancer in DCE-MRI data offer also means for image-based planning of biopsy interventions. One step in the MRI guided biopsy workflow is the alignment of the patient position with the preoperative MR images. In these images, the location and orientation of the coil localization unit can be inferred from a number of fiducial markers, which for this purpose have to be manually or semi-automatically detected by the user. In this study, we propose a method for precise, full-automatic localization of fiducial markers, on which basis a virtual localization unit can be subsequently placed in the image volume for the purpose of determining the parameters for needle navigation. The method is based on adaptive thresholding for separating breast tissue from background followed by rigid registration of marker templates. In an evaluation of 25 clinical cases comprising 4 different commercial coil array models and 3 different MR imaging protocols, the method yielded a sensitivity of 0.96 at a false positive rate of 0.44 markers per case. The mean distance deviation between detected fiducial centers and ground truth information that was appointed from a radiologist was 0.94mm.

Single-operator EUS-guided cholangiopancreatography for difficult pancreaticobiliary access (with video).

Science.gov (United States)

Brauer, Brian C; Chen, Yang K; Fukami, Norio; Shah, Raj J

2009-09-01

When conventional ERCP methods fail because of periampullary or ductal obstruction, EUS-guided cholangiopancreatography (EUS-CP) may aid in pancreaticobiliary access. To report our experience when using single-operator EUS-CP. An academic tertiary-referral center. Consecutive patients undergoing EUS-CP were prospectively identified. These patients had undergone failed attempt(s) at therapeutic ERCP. A data sheet was used to record indications, reasons for failed ERCP, EUS-CP visualization of the duct of interest, transpapillary or transenteric intervention, clinical follow-up, and complications. Technical success was decompression of the duct of interest. Clinical success was resolution of jaundice or a > or = 50% reduction in pain or narcotics, as applicable. Between February 2003 and June 2007, EUS-CP was attempted in 20 patients (11 men, 9 women; mean [SD] age 58 +/- 14.9 years). Indications included jaundice (n = 8), biliary stones (n = 3), chronic pancreatitis (n = 6), acute pancreatitis (n = 2), and papillary stenosis (n = 1). Reasons for failed ERCP included periampullary mass (n = 8), intradiverticular papillae (n = 4), and pancreatic duct (PD) stricture (n = 7) or stone (n = 1). Technical success was achieved in 18 of 20 patients (90%). Biliary decompression was obtained in 11 of 12 patients (92%) (7 transpapillary and 4 transenteric-transcholedochal). Pancreatic decompression was obtained in 7 of 8 patients (88%) (3 transpapillary, 4 transgastric). On follow-up, clinical improvement was noted in 15 of 20 patients (70%). For treatment of pain associated with chronic pancreatitis, pain scores decreased by a mean of 1.75 (P = .18). Complications (in 2 of 20 [10%]) included perforation (n = 1) and respiratory failure (n = 1). A single-center nonrandomized observational study with a small patient population. At our academic referral center, single-operator EUS-CP provided decompression of obstructed ducts and may be performed after a failed attempt at

Novel ex vivo model for hands-on teaching of and training in EUS-guided biliary drainage: creation of "Mumbai EUS" stereolithography/3D printing bile duct prototype (with videos)

NARCIS (Netherlands)

Dhir, Vinay; Itoi, Takao; Fockens, Paul; Perez-Miranda, Manuel; Khashab, Mouen A.; Seo, Dong Wan; Yang, Ai Ming; Lawrence, Khek Yu; Maydeo, Amit

2015-01-01

Background: EUS-guided biliary drainage (EUS-BD) has emerged as an alternative rescue method in patients with failed ERCP. Opportunities for teaching and training are limited because of a low case volume at most centers. Objective: To evaluate a stereolithography/3-dimensional (3D) printing bile

Comparison between skin-mounted fiducials and bone-implanted fiducials for image-guided neurosurgery

Science.gov (United States)

Rost, Jennifer; Harris, Steven S.; Stefansic, James D.; Sillay, Karl; Galloway, Robert L., Jr.

2004-05-01

Point-based registration for image-guided neurosurgery has become the industry standard. While the use of intrinsic points is appealing because of its retrospective nature, affixing extrinsic objects to the head prior to scanning has been demonstrated to provide much more accurate registrations. Points of reference between image space and physical space are called fiducials. The extrinsic objects which generate those points are fiducial markers. The markers can be broken down into two classifications: skin-mounted and bone-implanted. Each has distinct advantages and disadvantages. Skin-mounted fiducials require simply sticking them on the patient in locations suggested by the manufacturer, however, they can move with tractions placed on the skin, fall off and perhaps the most dangerous problem, they can be replaced by the patient. Bone implanted markers being rigidly affixed to the skull do not present such problems. However, a minor surgical intervention (analogous to dental work) must be performed to implant the markers prior to surgery. Therefore marker type and use has become a decision point for image-guided surgery. We have performed a series of experiments in an attempt to better quantify aspects of the two types of markers so that better informed decisions can be made. We have created a phantom composed of a full-size plastic skull [Wards Scientific Supply] with a 500 ml bag of saline placed in the brain cavity. The skull was then sealed. A skin mimicking material, DragonSkinTM [SmoothOn Company] was painted onto the surface and allowed to dry. Skin mounted fiducials [Medtronic-SNT] and bone-implanted markers [Z-Kat]were placed on the phantom. In addition, three additional bone-implanted markers were placed (two on the base of the skull and one in the eye socket for use as targets). The markers were imaged in CT and 4 MRI sequences (T1-weighted, T2 weighted, SPGR, and a functional series.) The markers were also located in physical space using an Optotrak

Pancreatic duct drainage using EUS-guided rendezvous technique for stenotic pancreaticojejunostomy.

Science.gov (United States)

Takikawa, Tetsuya; Kanno, Atsushi; Masamune, Atsushi; Hamada, Shin; Nakano, Eriko; Miura, Shin; Ariga, Hiroyuki; Unno, Jun; Kume, Kiyoshi; Kikuta, Kazuhiro; Hirota, Morihisa; Yoshida, Hiroshi; Katayose, Yu; Unno, Michiaki; Shimosegawa, Tooru

2013-08-21

The patient was a 30-year-old female who had undergone excision of the extrahepatic bile duct and Roux-en-Y hepaticojejunostomy for congenital biliary dilatation at the age of 7. Thereafter, she suffered from recurrent acute pancreatitis due to pancreaticobiliary maljunction and received subtotal stomach-preserving pancreaticoduodenectomy. She developed a pancreatic fistula and an intra-abdominal abscess after the operation. These complications were improved by percutaneous abscess drainage and antibiotic therapy. However, upper abdominal discomfort and the elevation of serum pancreatic enzymes persisted due to stenosis from the pancreaticojejunostomy. Because we could not accomplish dilation of the stenosis by endoscopic retrograde cholangiopancreatography, we tried an endoscopic ultrasonography (EUS) guided rendezvous technique for pancreatic duct drainage. After transgastric puncture of the pancreatic duct using an EUS-fine needle aspiration needle, the guidewire was inserted into the pancreatic duct and finally reached to the jejunum through the stenotic anastomosis. We changed the echoendoscope to an oblique-viewing endoscope, then grasped the guidewire and withdrew it through the scope. The stenosis of the pancreaticojejunostomy was dilated up to 4 mm, and a pancreatic stent was put in place. Though the pancreatic stent was removed after three months, the patient remained symptom-free. Pancreatic duct drainage using an EUS-guided rendezvous technique was useful for the treatment of a stenotic pancreaticojejunostomy after pancreaticoduodenectomy.

Indications, results, and clinical impact of endoscopic ultrasound (EUS)-guided sampling in gastroenterology

DEFF Research Database (Denmark)

Dumonceau, Jean-Marc; Deprez, Pierre H; Jenssen, Christian

2017-01-01

For pancreatic solid lesions, ESGE recommends performing endoscopic ultrasound (EUS)-guided sampling as first-line procedure when a pathological diagnosis is required. Alternatively, percutaneous sampling may be considered in metastatic disease.Strong recommendation, moderate quality evidence.In ...

Technical aspects of endoscopic ultrasound (EUS)-guided sampling in gastroenterology: European Society of Gastrointestinal Endoscopy (ESGE) Technical Guideline - March 2017.

Science.gov (United States)

Polkowski, Marcin; Jenssen, Christian; Kaye, Philip; Carrara, Silvia; Deprez, Pierre; Gines, Angels; Fernández-Esparrach, Gloria; Eisendrath, Pierre; Aithal, Guruprasad P; Arcidiacono, Paolo; Barthet, Marc; Bastos, Pedro; Fornelli, Adele; Napoleon, Bertrand; Iglesias-Garcia, Julio; Seicean, Andrada; Larghi, Alberto; Hassan, Cesare; van Hooft, Jeanin E; Dumonceau, Jean-Marc

2017-10-01

For routine EUS-guided sampling of solid masses and lymph nodes (LNs) ESGE recommends 25G or 22G needles (high quality evidence, strong recommendation); fine needle aspiration (FNA) and fine needle biopsy (FNB) needles are equally recommended (high quality evidence, strong recommendation).When the primary aim of sampling is to obtain a core tissue specimen, ESGE suggests using 19G FNA or FNB needles or 22G FNB needles (low quality evidence, weak recommendation).ESGE recommends using 10-mL syringe suction for EUS-guided sampling of solid masses and LNs with 25G or 22G FNA needles (high quality evidence, strong recommendation) and other types of needles (low quality evidence, weak recommendation). ESGE suggests neutralizing residual negative pressure in the needle before withdrawing the needle from the target lesion (moderate quality evidence, weak recommendation).ESGE does not recommend for or against using the needle stylet for EUS-guided sampling of solid masses and LNs with FNA needles (high quality evidence, strong recommendation) and suggests using the needle stylet for EUS-guided sampling with FNB needles (low quality evidence, weak recommendation).ESGE suggests fanning the needle throughout the lesion when sampling solid masses and LNs (moderate quality evidence, weak recommendation).ESGE equally recommends EUS-guided sampling with or without on-site cytologic evaluation (moderate quality evidence, strong recommendation). When on-site cytologic evaluation is unavailable, ESGE suggests performance of three to four needle passes with an FNA needle or two to three passes with an FNB needle (low quality evidence, weak recommendation).For diagnostic sampling of pancreatic cystic lesions without a solid component, ESGE suggests emptying the cyst with a single pass of a 22G or 19G needle (low quality evidence, weak recommendation). For pancreatic cystic lesions with a solid component, ESGE suggests sampling of the solid component using the same technique as in the

Safety and Efficacy of Ultrasound-Guided Fiducial Marker Implantation for CyberKnife Radiation Therapy

Energy Technology Data Exchange (ETDEWEB)

Kim, Jae Hyun; Hong, Seong; Sook; Kim, Jung Hoon; Park, Hyun Jeong; Chang, Yun Woo; Chang, A Ram [Soonchunhyang University Seoul Hospital, Seoul (Korea, Republic of); Kwon, Seok Beom [Hallym University College of Medicine, Chuncheon (Korea, Republic of)

2012-06-15

To evaluate the safety and technical success rate of an ultrasound-guided fiducial marker implantation in preparation for CyberKnife radiation therapy. We retrospectively reviewed 270 percutaneous ultrasound-guided fiducial marker implantations in 77 patients, which were performed from June 2008 through March 2011. Of 270 implantations, 104 were implanted in metastatic lymph nodes, 96 were in the liver, 39 were in the pancreas, and 31 were in the prostate. During and after the implantation, major and minor procedure-related complications were documented. We defined technical success as the implantation enabling adequate treatment planning and CT simulation. The major and minor complication rates were 1% and 21%, respectively. One patient who had an implantation in the liver suffered severe abdominal pain, biloma, and pleural effusion, which were considered as major complication. Abdominal pain was the most common complication in 11 patients (14%). Among nine patients who had markers inserted in the prostate, one had transient hematuria for less than 24 hours, and the other experienced transient voiding difficulty. Of the 270 implantations, 261 were successful (97%). The reasons for unsuccessful implantations included migration of fiducial markers (five implantations, 2%) and failure to discriminate the fiducial markers (three implantations, 1%). Among the unsuccessful implantation cases, six patients required additional procedures (8%). The symptomatic complications following ultrasound-guided percutaneous implantation of fiducial markers are relatively low. However, careful consideration of the relatively higher rate of migration and discrimination failure is needed when performing ultrasound-guided percutaneous implantations of fiducial markers.

Endoscopic ultrasound-guided pancreatic fluid collections' transmural drainage outcomes in 100 consecutive cases of pseudocysts and walled off necrosis: a single-centre experience from the United Kingdom.

Science.gov (United States)

Shekhar, Chander; Maher, Ben; Forde, Colm; Mahon, Brinder Singh

2017-11-09

Endoscopic ultrasound-guided drainage is a minimally invasive first-line modality for the drainage of pancreatic fluid collection (PFC) resulting in a shorter hospital stay and less morbidity compared with surgical cystogastrostomy. Our aim is to evaluate potential differences in the outcomes of endoscopic ultrasound (EUS) guided transmural drainage (EUS-TD) drainage of pancreatic pseudocyst (PP) and walled-off necrosis (WON). We retrospectively reviewed 100 consecutive EUS-guided drainages of PFC utilising EUS reports; clinical notes and imaging with follow-up (FU) to 12 months. All procedures were undertaken under conscious sedation with EUS guidance alone (without fluoroscopy) and placement of plastic double pigtail stents. In these 100 sequential cases, there were 78 cases of PP and 22 cases of WON. All 22/22(100%) cases of WON had successful EUS-guided stent placement. In 2/22(9%), there was little or no clinical improvement. These two patients required further computed tomography (CT)-guided drainage and one of these patients (1/22) (4.5%) developed recurrence within 12 months FU after removal of stents. In case of PP, overall stent placement was successful in 76/78 (97%) patients, but 6/78(8%) required 2nd EUS procedure after failure to show clinical improvement; 3/78(2.5%) required further CT-guided drainage. The overall complication rate was 9%(9/100) with 4%(4/100) requiring endoscopic or CT-guided intervention with no overall 30-day mortality. This is the largest series from a single UK centre demonstrating that EUS-guided cystogastrostomy of PFC drainage using plastic double pigtail stents is sufficient in majority of cases with PFC including that of WON, with or without infection.

Asian EUS Cup-05: Successful management of peripancreatic tumors by endoscopic ultrasound-guided radiofrequency ablation

OpenAIRE

Oh, Dongwook; Seo, Dong Wan

2017-01-01

Background: Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) could be used as an effective alternative treatment for peripancreatic tumor. Herein, we reported a case of adrenal adenoma which was treated by EUS-RFA. Case Report: A 38-year-old woman presented with ?moon face,? ?buffalo hump,? and weight gain of 9 kg in 12 months. Initial contrast-enhanced abdominal computed tomography showed a 2.8 cm left adrenal mass, and the patient was diagnosed with Cushing?s syndrome due to l...

Indications, results, and clinical impact of endoscopic ultrasound (EUS)-guided sampling in gastroenterology: European Society of Gastrointestinal Endoscopy (ESGE) Clinical Guideline - Updated January 2017.

Science.gov (United States)

Dumonceau, Jean-Marc; Deprez, Pierre H; Jenssen, Christian; Iglesias-Garcia, Julio; Larghi, Alberto; Vanbiervliet, Geoffroy; Aithal, Guruprasad P; Arcidiacono, Paolo G; Bastos, Pedro; Carrara, Silvia; Czakó, László; Fernández-Esparrach, Gloria; Fockens, Paul; Ginès, Àngels; Havre, Roald F; Hassan, Cesare; Vilmann, Peter; van Hooft, Jeanin E; Polkowski, Marcin

2017-07-01

For pancreatic solid lesions, ESGE recommends performing endoscopic ultrasound (EUS)-guided sampling as first-line procedure when a pathological diagnosis is required. Alternatively, percutaneous sampling may be considered in metastatic disease.Strong recommendation, moderate quality evidence.In the case of negative or inconclusive results and a high degree of suspicion of malignant disease, ESGE suggests re-evaluating the pathology slides, repeating EUS-guided sampling, or surgery.Weak recommendation, low quality evidence.In patients with chronic pancreatitis associated with a pancreatic mass, EUS-guided sampling results that do not confirm cancer should be interpreted with caution.Strong recommendation, low quality evidence.For pancreatic cystic lesions (PCLs), ESGE recommends EUS-guided sampling for biochemical analyses plus cytopathological examination if a precise diagnosis may change patient management, except for lesions ≤ 10 mm in diameter with no high risk stigmata. If the volume of PCL aspirate is small, it is recommended that carcinoembryonic antigen (CEA) level determination be done as the first analysis.Strong recommendation, low quality evidence.For esophageal cancer, ESGE suggests performing EUS-guided sampling for the assessment of regional lymph nodes (LNs) in T1 (and, depending on local treatment policy, T2) adenocarcinoma and of lesions suspicious for metastasis such as distant LNs, left liver lobe lesions, and suspected peritoneal carcinomatosis.Weak recommendation, low quality evidence.For lymphadenopathy of unknown origin, ESGE recommends performing EUS-guided (or alternatively endobronchial ultrasound [EBUS]-guided) sampling if the pathological result is likely to affect patient management and no superficial lymphadenopathy is easily accessible.Strong recommendation, moderate quality evidence.In the case of solid liver masses suspicious for metastasis, ESGE suggests performing EUS-guided sampling if the pathological result is likely

Comparison of CT Fluoroscopy-Guided Manual and CT-Guided Robotic Positioning System for In Vivo Needle Placements in Swine Liver

International Nuclear Information System (INIS)

Cornelis, F.; Takaki, H.; Laskhmanan, M.; Durack, J. C.; Erinjeri, J. P.; Getrajdman, G. I.; Maybody, M.; Sofocleous, C. T.; Solomon, S. B.; Srimathveeravalli, G.

2015-01-01

PurposeTo compare CT fluoroscopy-guided manual and CT-guided robotic positioning system (RPS)-assisted needle placement by experienced IR physicians to targets in swine liver.Materials and MethodsManual and RPS-assisted needle placement was performed by six experienced IR physicians to four 5 mm fiducial seeds placed in swine liver (n = 6). Placement performance was assessed for placement accuracy, procedure time, number of confirmatory scans, needle manipulations, and procedure radiation dose. Intra-modality difference in performance for each physician was assessed using paired t test. Inter-physician performance variation for each modality was analyzed using Kruskal–Wallis test.ResultsPaired comparison of manual and RPS-assisted placements to a target by the same physician indicated accuracy outcomes was not statistically different (manual: 4.53 mm; RPS: 4.66 mm; p = 0.41), but manual placement resulted in higher total radiation dose (manual: 1075.77 mGy/cm; RPS: 636.4 mGy/cm; p = 0.03), required more confirmation scans (manual: 6.6; RPS: 1.6; p < 0.0001) and needle manipulations (manual: 4.6; RPS: 0.4; p < 0.0001). Procedure time for RPS was longer than manual placement (manual: 6.12 min; RPS: 9.7 min; p = 0.0003). Comparison of inter-physician performance during manual placement indicated significant differences in the time taken to complete placements (p = 0.008) and number of repositions (p = 0.04) but not in other study measures (p > 0.05). Comparison of inter-physician performance during RPS-assisted placement suggested statistically significant differences in procedure time (p = 0.02) and not in other study measures (p > 0.05).ConclusionsCT-guided RPS-assisted needle placement reduced radiation dose, number of confirmatory scans, and needle manipulations when compared to manual needle placement by experienced IR physicians, with equivalent accuracy

Comparison of CT Fluoroscopy-Guided Manual and CT-Guided Robotic Positioning System for In Vivo Needle Placements in Swine Liver

Energy Technology Data Exchange (ETDEWEB)

Cornelis, F.; Takaki, H. [Memorial Sloan-Kettering Cancer Center, Interventional Radiology Service, Department of Radiology (United States); Laskhmanan, M. [Perfint Healthcare Inc (India); Durack, J. C.; Erinjeri, J. P.; Getrajdman, G. I.; Maybody, M.; Sofocleous, C. T.; Solomon, S. B.; Srimathveeravalli, G., E-mail: srimaths@mskcc.org [Memorial Sloan-Kettering Cancer Center, Interventional Radiology Service, Department of Radiology (United States)

2015-10-15

PurposeTo compare CT fluoroscopy-guided manual and CT-guided robotic positioning system (RPS)-assisted needle placement by experienced IR physicians to targets in swine liver.Materials and MethodsManual and RPS-assisted needle placement was performed by six experienced IR physicians to four 5 mm fiducial seeds placed in swine liver (n = 6). Placement performance was assessed for placement accuracy, procedure time, number of confirmatory scans, needle manipulations, and procedure radiation dose. Intra-modality difference in performance for each physician was assessed using paired t test. Inter-physician performance variation for each modality was analyzed using Kruskal–Wallis test.ResultsPaired comparison of manual and RPS-assisted placements to a target by the same physician indicated accuracy outcomes was not statistically different (manual: 4.53 mm; RPS: 4.66 mm; p = 0.41), but manual placement resulted in higher total radiation dose (manual: 1075.77 mGy/cm; RPS: 636.4 mGy/cm; p = 0.03), required more confirmation scans (manual: 6.6; RPS: 1.6; p < 0.0001) and needle manipulations (manual: 4.6; RPS: 0.4; p < 0.0001). Procedure time for RPS was longer than manual placement (manual: 6.12 min; RPS: 9.7 min; p = 0.0003). Comparison of inter-physician performance during manual placement indicated significant differences in the time taken to complete placements (p = 0.008) and number of repositions (p = 0.04) but not in other study measures (p > 0.05). Comparison of inter-physician performance during RPS-assisted placement suggested statistically significant differences in procedure time (p = 0.02) and not in other study measures (p > 0.05).ConclusionsCT-guided RPS-assisted needle placement reduced radiation dose, number of confirmatory scans, and needle manipulations when compared to manual needle placement by experienced IR physicians, with equivalent accuracy.

Comparison of transhepatic and extrahepatic routes for EUS-guided rendezvous procedure for distal CBD obstruction.

Science.gov (United States)

Dhir, Vinay; Bhandari, Suryaprakash; Bapat, Mukta; Joshi, Nitin; Vivekanandarajah, Suhirdan; Maydeo, Amit

2013-04-01

EUS-guided rendezvous procedure (EUS-RV) can be done by the transhepatic (TH) or the extrahepatic (EH) route. There is no data on the preferred access route when both routes are available. To compare the success, complications, and duration of hospitalization for patients undergoing EUS-RV by the TH or the EH route. Patients with distal common bile duct (CBD) obstruction, who failed selective cannulation, underwent EUS-RV by the TH route through the stomach or the EH route through the duodenum. A total of 35 patients were analysed (17 TH, 18 EH). The mean procedure time was significantly longer for the TH group (34.4 vs. 25.7 min; p = 0.0004). There was no difference in the technical success (94.1 vs. 100%). However, the TH group had a higher incidence of post-procedure pain (44.1 vs. 5.5%; p = 0.017), bile leak (11.7 vs. 0; p = 0.228), and air under diaphragm (11.7 vs. 0; p = 0.228). All bile leaks were small and managed conservatively. Duration of hospitalization was significantly higher for the TH group (2.52 vs. 0.17 days; p = 0.015). EUS-RV has similar success rate by the TH or the EH route. However, the TH route has higher post-procedure pain, longer procedure time, and longer duration of hospitalization. The EH route should be preferred for EUS-RV in patients with distal CBD obstruction when both access routes are technically feasible.

Identifying indications for percutaneous (PTC) vs. endoscopic ultrasound (EUS)- guided "rendezvous" procedure in biliary obstruction and incomplete endoscopic retrograde cholangiography (ERC).

Science.gov (United States)

Albert, J G; Finkelmeier, F; Friedrich-Rust, M; Kronenberger, B; Trojan, J; Zeuzem, S; Sarrazin, C

2014-10-01

The variety of rendezvous (RV) procedures has recently been extended by EUS- and PTCD-guided procedures as a complementary means to conventional ERCP. We have identified indication criteria and the potential of biliary PTCD-guided vs. EUS-guided RV. Consecutive patients with bile duct obstruction who underwent RV were included. In all, ERCP alone was unable to achieve treatment success. Indication, technical success, and outcome in PTCD- vs. EUS-guided RV were retrospectively compared to identify criteria that indicate preference of RV technique. Site of obstruction, clinical scenario (stenosis with abscess vs. no abscess) and reason for previous failure of ERC were evaluated. In 32 patients, three different indications for RV procedures were identified: First, a one-step access to assist in failed ERCP (type 1, intra-ductal RV); second, temporary drainage for prolonged treatment of complex biliary disease (type 2, intra-ductal RV), and drainage of cholangio-abscess with re-establishing bile outflow (type 3, intra-abscess RV). Indication of PTCD- vs. EUS-guided rendezvous was competitive in type 1, but exclusive in favor of PTCD in types 2 and 3. The site of biliary obstruction indicated the anatomic location of RV procedures. This classification may help to define inclusion criteria for prospective studies on biliary RV procedures. Choice of therapeutic strategy depends on the anatomic location of the biliary obstruction and the type of the biliary lesion. PTCD-guided RV might improve outcome in cholangio-abscess. © Georg Thieme Verlag KG Stuttgart · New York.

EUS-guided drainage of pancreatic fluid collections using a novel lumen-apposing metal stent on an electrocautery-enhanced delivery system: a large retrospective study (with video).

Science.gov (United States)

Rinninella, Emanuele; Kunda, Rastislav; Dollhopf, Markus; Sanchez-Yague, Andres; Will, Uwe; Tarantino, Ilaria; Gornals Soler, Joan; Ullrich, Sebastian; Meining, Alexander; Esteban, Josè Miguel; Enz, Thomas; Vanbiervliet, Geoffroy; Vleggaar, Frank; Attili, Fabia; Larghi, Alberto

2015-12-01

A lumen-apposing, self-expanding metal stent incorporated in an electrocautery-enhanced delivery system for EUS-guided drainage of pancreatic fluid collections (PFCs) recently has become available. The aim of this study was to analyze the safety and clinical effectiveness of this newly developed device in this clinical setting. This was a retrospective analysis of all consecutive patients with PFCs who underwent EUS-guided drainage using the study device in 13 European centers. Ninety-three patients with PFCs (80% with complex collections) underwent drainage using the study device. Penetration of the PFC was accomplished directly with the study device in 74.2% of patients, and successful stent placement was accomplished in all but 1 patient, mostly without fluoroscopic assistance. Direct endoscopic necrosectomy (DEN) was carried out in 31 of 52 cases (59.6%) of walled-off necrosis and in 2 of 4 cases (50%) of acute peripancreatic fluid collection. Complete resolution of the PFC was obtained in 86 cases (92.5%), with no recurrence during follow-up. Treatment failure occurred in 6 patients because of persistent infection requiring surgery (n = 3), perforation and massive bleeding caused by the nasocystic drainage catheter (NCDC) (n = 2), and the need for a larger opening to extract large necrotic tissue pieces (n = 1). Major adverse events occurred in 5 patients (perforation and massive bleeding caused by the NCDC in 2 patients, 1 pneumoperitoneum and 1 stent dislodgement during DEN, and 1 postdrainage infection) and were mostly not related to the drainage procedure. EUS-guided drainage with the electrocautery-enhanced delivery system is a safe, easy to perform, and a highly effective minimally invasive treatment modality for PFCs. Copyright © 2015 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

Endoscopic ultrasonography-guided pancreatic duct access: techniques and literature review of pancreatography, transmural drainage and rendezvous techniques.

Science.gov (United States)

Itoi, Takao; Kasuya, Kazuhiko; Sofuni, Atsushi; Itokawa, Fumihide; Kurihara, Toshio; Yasuda, Ichiro; Nakai, Yousuke; Isayama, Hiroyuki; Moriyasu, Fuminori

2013-05-01

Endoscopic ultrasonography-guided (EUS)-guided pancreatic interventions have gained increasing attention. Here we review EUS-guided pancreatic duct (PD) access techniques and outcomes. EUS-guided PD intervention is divided into two types, antegrade and rendezvous techniques, following EUS-guided pancreatography. In the antegrade technique, pancreaticoenterostomy is carried out by stent placement between the PD and the stomach, duodenum, or jejunum. Transenteric antegrade PD stenting is conducted by stent placement, advancing anteriorly into the PD through the pancreatic tract. The rendezvous technique is carried out by using a guidewire through the papilla or anastomotic site for retrograde stent insertion. In terms of EUS-guided PD stenting, 11 case reports totaling 75 patients (35 normal anatomy, 40 altered anatomy) have been published. The technical success rate was greater than 70%. Early adverse events, including severe hematoma and severe pancreatitis,occurred in seven (63.6%) of 11 reports. Regarding the rendezvous technique, 12 case reports totaling 52 patients (22 normal anatomy, 30 altered anatomy) have been published. The technical success rate ranged from 25% to 100%. It was 48% in one report that involved more than 20 cases. Once stents were placed, all patients became free of symptoms. Early mild adverse events occurred in four (36.4%) of 11 reports. In conclusion, although it can be risky because of possible serious or even fatal adverse events, including pancreatic juice leakage, perforation and severe acute pancreatitis, EUS-PD access seems to be promising for treating symptomatic pancreatic diseases caused by PD stricture and pancreaticoenterostomy stricture. © 2013 The Authors. Digestive Endoscopy © 2013 Japan Gastroenterological Endoscopy Society.

Impact of EUS-guided FNA on management of gastric carcinoma

DEFF Research Database (Denmark)

Hassan, Hazem; Vilmann, Peter; Sharma, Vijay

2010-01-01

EUS is an integral part of the pretherapeutic evaluation program for patients with upper GI cancer.......EUS is an integral part of the pretherapeutic evaluation program for patients with upper GI cancer....

Rescue EUS-guided intrahepatic biliary drainage for malignant hilar biliary stricture after failed transpapillary re-intervention.

Science.gov (United States)

Minaga, Kosuke; Takenaka, Mamoru; Kitano, Masayuki; Chiba, Yasutaka; Imai, Hajime; Yamao, Kentaro; Kamata, Ken; Miyata, Takeshi; Omoto, Shunsuke; Sakurai, Toshiharu; Watanabe, Tomohiro; Nishida, Naoshi; Kudo, Masatoshi

2017-11-01

Treatment of unresectable malignant hilar biliary stricture (UMHBS) is challenging, especially after failure of repeated transpapillary endoscopic stenting. Endoscopic ultrasonography-guided intrahepatic biliary drainage (EUS-IBD) is a recent technique for intrahepatic biliary decompression, but indications for its use for complex hilar strictures have not been well studied. The aim of this study was to assess the feasibility and safety of EUS-IBD for UMHBS after failed transpapillary re-intervention. Retrospective analysis of all consecutive patients with UMHBS of Bismuth II grade or higher who, between December 2008 and May 2016, underwent EUS-IBD after failed repeated transpapillary interventions. The technical success, clinical success, and complication rates were evaluated. Factors associated with clinical ineffectiveness of EUS-IBD were explored. A total of 30 patients (19 women, median age 66 years [range 52-87]) underwent EUS-IBD for UMHBS during the study period. Hilar biliary stricture morphology was classified as Bismuth II, III, or IV in 5, 13, and 12 patients, respectively. The median number of preceding endoscopic interventions was 4 (range 2-14). EUS-IBD was required because the following procedures failed: duodenal scope insertion (n = 4), accessing the papilla after duodenal stent insertion (n = 5), or achieving desired intrahepatic biliary drainage (n = 21). Technical success with EUS-IBD was achieved in 29 of 30 patients (96.7%) and clinical success was attained in 22 of these 29 (75.9%). Mild peritonitis occurred in three of 30 (10%) and was managed conservatively. Stent dysfunction occurred in 23.3% (7/30). There was no procedure-related mortality. On multivariable analysis, Bismuth IV stricture predicted clinical ineffectiveness (odds ratio = 12.7, 95% CI 1.18-135.4, P = 0.035). EUS-IBD may be a feasible and effective rescue alternative with few major complications after failed transpapillary endoscopic re-intervention in patients

An international multicenter study comparing EUS-guided pancreatic duct drainage with enteroscopy-assisted endoscopic retrograde pancreatography after Whipple surgery.

Science.gov (United States)

Chen, Yen-I; Levy, Michael J; Moreels, Tom G; Hajijeva, Gulara; Will, Uwe; Artifon, Everson L; Hara, Kazuo; Kitano, Masayuki; Topazian, Mark; Abu Dayyeh, Barham; Reichel, Andreas; Vilela, Tiago; Ngamruengphong, Saowanee; Haito-Chavez, Yamile; Bukhari, Majidah; Okolo, Patrick; Kumbhari, Vivek; Ismail, Amr; Khashab, Mouen A

2017-01-01

Endoscopic management of post-Whipple pancreatic adverse events (AEs) with enteroscopy-assisted endoscopic retrograde pancreatography (e-ERP) is associated with high failure rates. EUS-guided pancreatic duct drainage (EUS-PDD) has shown promising results; however, no comparative data have been done for these 2 modalities. The goal of this study is to compare EUS-PDD with e-ERP in terms of technical success (PDD through dilation/stent), clinical success (improvement/resolution of pancreatic-type symptoms), and AE rates in patients with post-Whipple anatomy. This is an international multicenter comparative retrospective study at 7 tertiary centers (2 United States, 2 European, 2 Asian, and 1 South American). All consecutive patients who underwent EUS-PDD or e-ERP between January 2010 and August 2015 were included. In total, 66 patients (mean age, 57 years; 48% women) and 75 procedures were identified with 40 in EUS-PDD and 35 in e-ERP. Technical success was achieved in 92.5% of procedures in the EUS-PDD group compared with 20% of procedures in the e-ERP group (OR, 49.3; P procedures in the EUS-PDD group compared with 23.1% in the e-ERP group (OR, 23.3; P Procedure time and length of stay were not significantly different between the 2 groups. EUS-PDD is superior to e-ERP in post-Whipple anatomy in terms of efficacy with acceptable safety. As such, EUS-PDD should be considered as a potential first-line treatment in post-pancreaticoduodenectomy anatomy when necessary expertise is available. Copyright © 2017 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

SU-F-J-43: Positional Variation of Implanted Fiducial Markers Over the Course of Image Guided Radiotherapy for Pancreatic Cancer

Energy Technology Data Exchange (ETDEWEB)

Shen, S; Jacob, R; Popple, R; Wu, X; Cardan, R; Brezovich, I [University Alabama Birmingham, Birmingham, AL (United States)

2016-06-15

Purpose: Pancreas is a soft-tissue organ, implanted fiducials can change positions due to migration or tissue deformation. This study quantified positional variation of fiducials in IGRT for pancreatic cancer. Methods: 20 patients had at least 3 gold fiducials implanted in pancreas under EUS guidance. Patients had 4D-CT simulation for gated treatment. Daily gated OBI kV images (Turebeam) were used for positional alignment with fiducials for total of 25 or 28 fractions. Relative distances among 3 fiducials (d{sub 1–} {sub 2}, d{sub 1–3}, d{sub 2–3}) were measured from 4D-CT end-of-expiration phase bin; and from gated kV images in first, mid, and last fraction (n=180). Results: The median duration between implant and simulation was 11 (range 0–41) days. The median duration between simulation and first fraction was 17 (range 8–24) days. The median relative distance was 12 (range 4–78) mm for d{sub 1–2}, 24 (range 6–80) mm for d{sub 1–3}, and 19 (range 5–63) mm for d{sub 2–3}. The median deviation was 1 mm for d{sub 1–2}, d{sub 1–3}, d{sub 2–3} between simulation and first fraction, first and mid fraction, mid and last fraction (n=180). Two patients (10%) had deviation >= 5 mm (5, 11 mm) between simulation and first fraction. One patient (5%) had deviation >= 5 mm (11 mm) between first and mid fraction. No patient (0%) had deviation >= 5 mm between mid and last fraction. In all 3 cases with deviation >=5 mm, only one fiducial was significantly deviated. No clear evidence that deviation size was associated with time interval between implant and first fraction. Conclusion: Implanted gold fiducials were quite stable over time in their relative positions in pancreas. Our data suggested at least 3 fiducials are needed. In cases that one fiducial was significantly deviated in daily kV images, this fiducial should be excluded in image guidance.

EUS-guided rendezvous for difficult biliary cannulation using a standardized algorithm: a multicenter prospective pilot study (with videos).

Science.gov (United States)

Iwashita, Takuji; Yasuda, Ichiro; Mukai, Tsuyoshi; Iwata, Keisuke; Ando, Nobuhiro; Doi, Shinpei; Nakashima, Masanori; Uemura, Shinya; Mabuchi, Masatoshi; Shimizu, Masahito

2016-02-01

Biliary cannulation is necessary in therapeutic ERCP for biliary disorders. EUS-guided rendezvous (EUS-RV) can salvage failed cannulation. Our aim was to determine the safety and efficacy of EUS-RV by using a standardized algorithm with regard to the endoscope position in a prospective study. EUS-RV was attempted after failed cannulation in 20 patients. In a standardized approach, extrahepatic bile duct (EHBD) cannulation was preferentially attempted from the second portion of the duodenum (D2) followed by additional approaches to the EHBD from the duodenal bulb (D1) or to the intrahepatic bile duct from the stomach, if necessary. A guidewire was placed in an antegrade fashion into the duodenum. After the guidewire was placed, the endoscope was exchanged for a duodenoscope to complete the cannulation. The bile duct was accessed from the D2 in 10 patients, but from the D1 in 5 patients and the stomach in 4 patients because of no dilation or tumor invasion at the distal EHBD. In the remaining patient, biliary puncture was not attempted due to the presence of collateral vessels. The guidewire was successfully manipulated in 80% of patients: 100% (10/10) with the D2 approach and 66.7% (6/9) with other approaches. The overall success rate was 80% (16/20). Failed EUS-RV was salvaged with a percutaneous approach in 2 patients, repeat ERCP in 1 patient, and conservative management in 1 patient. Minor adverse events occurred in 15% of patients (3/20). EUS-RV is a safe and effective salvage method. Using EUS-RV to approach the EHBD from the D2 may improve success rates. Copyright © 2016 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

EUS-FNA for the Diagnosis of Retroperitoneal Primitive Neuroectodermal Tumor

Directory of Open Access Journals (Sweden)

Aijaz A. Sofi

2011-01-01

Full Text Available Primitive neuroectodermal tumor (PNET is a rare “small round blue cell tumor” that is diagnosed by open biopsy or percutaneous biopsy of the lesion under radiologic guidance. In this case report, we present a novel approach to the diagnosis of a retroperitoneal PNET by endoscopic ultrasound- (EUS- guided fine needle aspiration (FNA. A 35-year-old man presented with the history of left-sided flank pain and swelling of 3-weeks duration. Computerized tomography (CT scan of his abdomen revealed a 12.8 × 13 × 12.5 cm cystic and solid mass arising from the retroperitoneum and displacing the third and fourth portions of the duodenum. He underwent EUS which revealed a well-circumscribed heterogeneous mass abutting the inferior portion of the stomach. EUS-FNA of the mass revealed malignant cells consistent with primitive neuroectodermal tumor (PNET/Ewing's sarcoma. EUS-guided FNA is an appropriate technique for diagnosing retroperitoneal PNET/Ewing's sarcoma.

Visibility of fiducial markers used for image-guided radiation therapy on optical coherence tomography for registration with CT: An esophageal phantom study.

Science.gov (United States)

Jelvehgaran, Pouya; Alderliesten, Tanja; Weda, Jelmer J A; de Bruin, Martijn; Faber, Dirk J; Hulshof, Maarten C C M; van Leeuwen, Ton G; van Herk, Marcel; de Boer, Johannes F

2017-12-01

Optical coherence tomography (OCT) is of interest to visualize microscopic esophageal tumor extensions to improve tumor delineation for radiation therapy (RT) planning. Fiducial marker placement is a common method to ensure target localization during planning and treatment. Visualization of these fiducial markers on OCT permits integrating OCT and computed tomography (CT) images used for RT planning via image registration. We studied the visibility of 13 (eight types) commercially available solid and liquid fiducial markers in OCT images at different depths using dedicated esophageal phantoms and evaluated marker placement depth in clinical practice. We designed and fabricated dedicated esophageal phantoms, in which three layers mimic the anatomical wall structures of a healthy human esophagus. We successfully implanted 13 commercially available fiducial markers that varied in diameter and material property at depths between 0.5 and 3.0 mm. The resulting esophageal phantoms were imaged with OCT, and marker visibility was assessed qualitatively and quantitatively using the contrast-to-background-noise ratio (CNR). The CNR was defined as the difference between the mean intensity of the fiducial markers and the mean intensity of the background divided by the standard deviation of the background intensity. To determine whether, in current clinical practice, the implanted fiducial markers are within the OCT visualization range (up to 3.0 mm depth), we retrospectively measured the distance of 19 fiducial markers to the esophageal lumen on CT scans of 16 esophageal cancer patients. In the esophageal phantoms, all the included fiducial markers were visible on OCT at all investigated depths. Solid fiducial markers were better visible on OCT than liquid fiducial markers with a 1.74-fold higher CNR. Although fiducial marker identification per type and size was slightly easier for superficially implanted fiducial markers, we observed no difference in the ability of OCT to

Fiducial marker guided stereotactic liver radiotherapy: Is a time delay between marker implantation and planning CT needed?

DEFF Research Database (Denmark)

Worm, Esben S; Bertholet, Jenny; Høyer, Morten

2016-01-01

To minimize the risk of marker migration in fiducial marker guided liver SBRT it is common to add a delay of a week between marker implantation and planning CT. This study found that such a delay is unnecessary and could be avoided to minimize the treatment preparation time.......To minimize the risk of marker migration in fiducial marker guided liver SBRT it is common to add a delay of a week between marker implantation and planning CT. This study found that such a delay is unnecessary and could be avoided to minimize the treatment preparation time....

Fluid collection after partial pancreatectomy: EUS drainage and long-term follow-up.

Science.gov (United States)

Caillol, Fabrice; Godat, Sebastien; Turrini, Olivier; Zemmour, Christophe; Bories, Erwan; Pesenti, Christian; Ratone, Jean Phillippe; Ewald, Jacques; Delpero, Jean Robert; Giovannini, Marc

2018-03-29

Postoperative fluid collection due to pancreatic leak is the most frequent complication after pancreatic surgery. Endoscopic ultrasound (EUS)-guided drainage of post-pancreatic surgery fluid collection is the gold standard procedure; however, data on outcomes of this procedure are limited. The primary endpoint of our study was relapse over longterm followup, and the secondary endpoint was the efficiency and safety of EUS-guided drainage of post-pancreatic surgery fluid collection. This retrospective study was conducted at a single center from December 2008 to April 2016. Global morbidity was defined as the occurrence of an event involving additional endoscopic procedures, hospitalization, or interventional radiologic or surgical procedures. EUS-guided drainage was considered a clinical failure if surgery was required to treat a relapse after stent removal. Fortyone patients were included. The technical success rate was 100%. Drainage was considered a clinical success in 93% (39/41) of cases. Additionally, 19 (46%) complications were identified as global morbidity. The duration between surgery and EUS-guided drainage was not a significantly related factor for morbidity rate (P = 0.8); however, bleeding due to arterial injuries (splenic artery and gastroduodenal artery) from salvage drainage procedures occurred within 25 days following the initial surgery. There was no difference in survival between patients with and without complications. No relapse was reported during the followup (median: 44.75 months; range: 29.24 to 65.74 months). EUSguided drainage for post-pancreatic surgery fluid collection was efficient with no relapse during longterm followup. Morbidity rate was independent of the duration between the initial surgery and EUS-guided drainage; however, bleeding risk was likely more important in cases of early drainage.

Feasibility study of EUS-NOTES as a novel approach for peroral cholecysto-gastrostomy

DEFF Research Database (Denmark)

Saftoiu, Adrian; Vilmann, P; Bhutani, M S

2013-01-01

EUS-guided cholecysto-gastrostomy might be a useful minimally invasive procedure used for salvage drainage in advanced pancreaticobiliary cancers, but also for drainage of the gallbladder in acute cholecystitis in patients deemed unfit for laparoscopic surgery.......EUS-guided cholecysto-gastrostomy might be a useful minimally invasive procedure used for salvage drainage in advanced pancreaticobiliary cancers, but also for drainage of the gallbladder in acute cholecystitis in patients deemed unfit for laparoscopic surgery....

Fluorescence cytology with 5-aminolevulinic acid in EUS-guided FNA as a method for differentiating between malignant and benign lesions (with video).

Science.gov (United States)

Ikeura, Tsukasa; Takaoka, Makoto; Uchida, Kazushige; Shimatani, Masaaki; Miyoshi, Hideaki; Kato, Kota; Ohe, Chisato; Uemura, Yoshiko; Kaibori, Masaki; Kwon, A-Hon; Okazaki, Kazuichi

2015-01-01

EUS-guided FNA (EUS-FNA) has been increasingly performed to obtain specimens for the pathological evaluation of patients with GI and pancreaticobiliary masses as well as lymphadenopathies of unknown origin. Photodynamic diagnosis by using 5-aminolebulinic acid (ALA) has been reported to be useful for enabling the visual differentiation between malignant and normal tissue in various cancers. To evaluate the diagnostic accuracy of fluorescence cytology with ALA in EUS-FNA. A prospective study. A single center. A total of 28 consecutive patients who underwent EUS-FNA for the pathological diagnosis of a pancreaticobiliary mass lesion or intra-abdominal lymphadenopathy of unknown origin. Patients were orally administered ALA 3 to 6 hours before EUS-FNA. The sample was obtained via EUS-FNA for fluorescence cytology and conventional cytology. A single gastroenterologist performed the fluorescence cytology by using fluorescence microscopy after the procedure, independently of the conventional cytology by pathologists. The accuracy of fluorescence cytology with ALA in the differentiation between benign and malignant lesions by comparing the results of fluorescence cytology with the final diagnosis. Of the 28 patients included in the study, 22 were considered as having malignant lesions and 6 patients as having benign lesions. Fluorescence cytology could correctly discriminate between benign and malignant lesions in all patients. Therefore, both the sensitivity and specificity of fluorescence cytology were 100% in our study. Fluorescence cytology was performed by only 1 gastroenterologist with a small number of patients. Fluorescence cytology with ALA in EUS-FNA may be an effective and simple method for differentiating between benign and malignant lesions. Copyright © 2015 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

EUS needle identification comparison and evaluation (NICE) study (with videos)

Science.gov (United States)

Tang, Shou-jiang; Vilmann, Andreas S.; Saftoiu, Adrian; Wang, Wanmei; Streba, Costin; Fink, Peter P.; Griswold, Michael; Wu, Ruonan; Dietrich, Christoph F.; Jenssen, Christian; Hocke, Michael; Kantowski, Marcus; Pohl, Jürgen; Fockens, Paul; Annema, Jouke T.; van der Heijden, Erik H.F.M.; Havre, Roald Flesland; Pham, Khanh Do-Cong; Kunda, Rastislav; Deprez, Pierre H.; Mariana, Jinga; Vazquez-Sequeiros, Enrique; Larghi, Alberto; Buscarini, Elisabetta; Fusaroli, Pietro; Lahav, Maor; Puri, Rajesh; Garg, Pramod Kumar; Sharma, Malay; Maluf-Filho, Fauze; Sahai, Anand; Brugge, William R.; Lee, Linda S.; Aslanian, Harry R.; Wang, Andrew Y.; Shami, Vanessa M.; Markowitz, Arnold; Siddiqui, Ali A.; Mishra, Girish; Scheiman, James M.; Isenberg, Gerard; Siddiqui, Uzma D.; Shah, Raj J.; Buxbaum, James; Watson, Rabindra R.; Willingham, Field F.; Bhutani, Manoop S.; Levy, Michael J.; Harris, Cynthia; Wallace, Michael B.; Nolsøe, Christian Pállson; Lorentzen, Torben; Bang, Niels; Sørensen, Sten Mellerup; Gilja, Odd Helge; D’Onofrio, Mirko; Piscaglia, Fabio; Gritzmann, Norbert; Radzina, Maija; Sparchez, Zeno Adrian; Sidhu, Paul S.; Freeman, Simon; McCowan, Timothy C.; de Araujo, Cyrillo Rodrigues; Patel, Akash; del Ali, Mohammad A; Campbell, Garth; Chen, Edward; Vilmann, Peter

2017-01-01

Background and Aims Endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) or biopsy is widely practiced. Optimal sonographic visualization of the needle is critical for image guided interventions. There are several commercially available needles but no bench-top testing and direct comparison of these needles to reveal their inherent echogenicity. The aims are to provide bench-top data that can be used to guide clinical applications and to promote future device research and development. Methods Descriptive bench-top testing and comparison. Bench-top testing of 8 commonly used EUS-FNA needles (all of 22 gauge in size): SonoTip Pro Control (Medi-Globe); Expect Slimline (Boston Scientific); EchoTip, EchoTip Ultra, EchoTip ProCore High Definition, (Cook Medical); ClearView (Conmed); EZ Shot2 (Olympus); BNX (Beacon Endoscopic); and 2 new prototype needles that are coated by echogenic polymers by Medi-Globe. Blinded evaluation of standardized and unedited videos by 43 EUS endoscopists and 17 radiologists specialized in gastrointestinal ultrasound examination that is unfamiliar with EUS needle devices. Results There was no significant difference in the ratings and rankings of these needles between endosonographers and radiologists. Overall, one prototype needle was rated as the best, ranking 10% to 40% higher than all other needles (p<0.01). Among the commercially available needles, the EchoTip Ultra needle and the ClearView needle were top choices. The EZ Shot 2 needle was ranked statistically lower than other needles (30%–75% worse, p<0.001). Conclusions All FNA needles have their inherent and different echogenicity, and these differences are similarly recognized by EUS endoscopists and radiologists. Needles with polymeric coating from the entire shaft to the needle tip may offer better echogenicity. PMID:26873530

Metastatic tonsillar squamous cell carcinoma masquerading as a pancreatic cystic tumor and diagnosed by EUS-guided FNA.

Science.gov (United States)

Glass, Ryan; Andrawes, Sherif A; Hamele-Bena, Diane; Tong, Guo-Xia

2017-11-01

Metastatic carcinoma to the pancreas is uncommon and head and neck squamous carcinoma metastatic to the pancreas is extremely rare. Metastatic squamous cell carcinoma to the pancreas presents a unique diagnostic challenge: in addition to mimicking the rare primary squamous cell carcinoma of the pancreas based on cytologic, histologic, and immunohistochemical features, it may be mistaken for a cystic neoplasm of the pancreas because of its high predilection for cystic degeneration in metastatic sites. Herein, we report a case of tonsillar squamous cell carcinoma with a cystic pancreatic metastasis diagnosed by ultrasound-guided fine needle aspiration biopsy (EUS-FNA). This represents a third reported case of metastatic squamous cell carcinoma to the pancreas from the head and neck region. Metastatic squamous cell carcinoma should be considered in the differential diagnosis of EUS-FNA during evaluation of pancreatic cystic lesion. © 2017 Wiley Periodicals, Inc.

K.s. Micro-implant placement guide.

Science.gov (United States)

Sharma, K; Sangwan, A

2014-09-01

A one of the greatest concerns with orthodontic mini-implants is risk of injury to dental roots during placement is, especially when they are inserted between teeth. Many techniques have been used to facilitate safe placement of interradicular miniscrews. Brass Wires or metallic markers are easy to place in the interproximal spaces, but because their relative positions may be inconsistent in different radio -graphic views, they are not always accurate. K.S. micro implant placement guide suggested in this article is simple design and easy in fabrication, required minimal equipment for fabrication and does not disturb the existing appliance system, clearly located in the radiograph and the mini-screw can be easily inserted through the guide reducing the chance of implant misplacement.

K.S. Micro-Implant Placement Guide

OpenAIRE

Sharma, K; Sangwan, A

2014-01-01

A one of the greatest concerns with orthodontic mini-implants is risk of injury to dental roots during placement is, especially when they are inserted between teeth. Many techniques have been used to facilitate safe placement of interradicular miniscrews. Brass Wires or metallic markers are easy to place in the interproximal spaces, but because their relative positions may be inconsistent in different radio -graphic views, they are not always accurate. K.S. micro implant placement guide sugge...

EUS Elastography: Advances in Diagnostic EUS of the Pancreas

International Nuclear Information System (INIS)

Lee, Tae Hee; Cha, Sang Woo; Cho, Young Deok

2012-01-01

Elastography is an imaging modality for the evaluation of tissue stiffness, which has been used for the analysis of superficial organs, such as those of the breast and prostate. The measurement of tissue elasticity has been reported to be useful for the diagnosis and differentiation of tumors, which are stiffer than normal tissues. Endoscopic ultrasonography elastography (EUS-EG) is a promising imaging technique with a high degree of accuracy for the differential diagnosis of solid pancreatic tumors. Recent introduction of second generation EUS-EG allows for the quantitative analysis of tissue stiffness. Here, we review our knowledge and preliminary experience with the use of EUS-elastography for the diagnosis of pancreatic disease.

Quantification and comparison of visibility and image artifacts of a new liquid fiducial marker in a lung phantom for image-guided radiation therapy

Energy Technology Data Exchange (ETDEWEB)

Scherman Rydhög, Jonas, E-mail: per.jonas.scherman.rydhoeg@regionh.dk; Munck af Rosenschöld, Per [Department of Oncology, Section of Radiotherapy, 3994, Rigshospitalet, Blegdamsvej 9, Copenhagen 2100, Denmark and Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, Copenhagen 2100 (Denmark); Irming Jølck, Rasmus; Andresen, Thomas Lars [DTU Nanotech, Department of Micro- and Nanotechnology, Center for Nanomedicine and Theranostics, Technical University of Denmark, Building 423, Kongens Lyngby 2800 (Denmark)

2015-06-15

Purpose: A new biodegradable liquid fiducial marker was devised to allow for easy insertion in lung tumors using thin needles. The purpose of this study was to evaluate the visibility of the liquid fiducial markers for image-guided radiation therapy and compare to existing solid fiducial markers and to one existing liquid fiducial marker currently commercially available. Methods: Fiducial marker visibility was quantified in terms of contrast to noise ratio (CNR) on planar kilovoltage x-ray images in a thorax phantom for different concentrations of the radio-opaque component of the new liquid fiducial marker, four solid fiducial markers, and one existing liquid fiducial marker. Additionally, the image artifacts produced on computer tomography (CT) and cone-beam CT (CBCT) of all fiducial markers were quantified. Results: The authors found that the new liquid fiducial marker with the highest concentration of the radio-opaque component had a CNR > 2.05 for 62/63 exposures, which compared favorably to the existing solid fiducial markers and to the existing liquid fiducial marker evaluated. On CT and CBCT, the new liquid fiducial marker with the highest concentration produced lower streaking index artifact (30 and 14, respectively) than the solid gold markers (113 and 20, respectively) and the existing liquid fiducial marker (39 and 20, respectively). The size of the image artifact was larger for all of the liquid fiducial markers compared to the solid fiducial markers because of their larger physical size. Conclusions: The visibility and the image artifacts produced by the new liquid fiducial markers were comparable to existing solid fiducial markers and the existing liquid fiducial marker. The authors conclude that the new liquid fiducial marker represents an alternative to the fiducial markers tested.

Internship guide : Work placements step by step

NARCIS (Netherlands)

Haag, Esther

2013-01-01

Internship Guide: Work Placements Step by Step has been written from the practical perspective of a placement coordinator. This book addresses the following questions : what problems do students encounter when they start thinking about the jobs their degree programme prepares them for? How do you

MR-guided stereotactic neurosurgery-comparison of fiducial-based and anatomical landmark transformation approaches

International Nuclear Information System (INIS)

Hunsche, S; Sauner, D; Maarouf, M; Hoevels, M; Luyken, K; Schulte, O; Lackner, K; Sturm, V; Treuer, H

2004-01-01

For application in magnetic resonance (MR) guided stereotactic neurosurgery, two methods for transformation of MR-image coordinates in stereotactic, frame-based coordinates exist: the direct stereotactic fiducial-based transformation method and the indirect anatomical landmark method. In contrast to direct stereotactic MR transformation, indirect transformation is based on anatomical landmark coregistration of stereotactic computerized tomography and non-stereotactic MR images. In a patient study, both transformation methods have been investigated with visual inspection and mutual information analysis. Comparison was done for our standard imaging protocol, including t2-weighted spin-echo as well as contrast enhanced t1-weighted gradient-echo imaging. For t2-weighted spin-echo imaging, both methods showed almost similar and satisfying performance with a small, but significant advantage for fiducial-based transformation. In contrast, for t1-weighted gradient-echo imaging with more geometric distortions due to field inhomogenities and gradient nonlinearity than t2-weighted spin-echo imaging, mainly caused by a reduced bandwidth per pixel, anatomical landmark transformation delivered markedly better results. Here, fiducial-based transformation yielded results which are intolerable for stereotactic neurosurgery. Mean Euclidian distances between both transformation methods were 0.96 mm for t2-weighted spin-echo and 1.67 mm for t1-weighted gradient-echo imaging. Maximum deviations were 1.72 mm and 3.06 mm, respectively

MR-guided stereotactic neurosurgery-comparison of fiducial-based and anatomical landmark transformation approaches

Energy Technology Data Exchange (ETDEWEB)

Hunsche, S [Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne (Germany); Sauner, D [Institute for Diagnostic and Interventional Radiology, Friedrich-Schiller-University of Jena, Jena (Germany); Maarouf, M [Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne (Germany); Hoevels, M [Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne (Germany); Luyken, K [Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne (Germany); Schulte, O [Department of Radiology, University of Cologne, Cologne (Germany); Lackner, K [Department of Radiology, University of Cologne, Cologne (Germany); Sturm, V [Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne (Germany); Treuer, H [Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne (Germany)

2004-06-21

For application in magnetic resonance (MR) guided stereotactic neurosurgery, two methods for transformation of MR-image coordinates in stereotactic, frame-based coordinates exist: the direct stereotactic fiducial-based transformation method and the indirect anatomical landmark method. In contrast to direct stereotactic MR transformation, indirect transformation is based on anatomical landmark coregistration of stereotactic computerized tomography and non-stereotactic MR images. In a patient study, both transformation methods have been investigated with visual inspection and mutual information analysis. Comparison was done for our standard imaging protocol, including t2-weighted spin-echo as well as contrast enhanced t1-weighted gradient-echo imaging. For t2-weighted spin-echo imaging, both methods showed almost similar and satisfying performance with a small, but significant advantage for fiducial-based transformation. In contrast, for t1-weighted gradient-echo imaging with more geometric distortions due to field inhomogenities and gradient nonlinearity than t2-weighted spin-echo imaging, mainly caused by a reduced bandwidth per pixel, anatomical landmark transformation delivered markedly better results. Here, fiducial-based transformation yielded results which are intolerable for stereotactic neurosurgery. Mean Euclidian distances between both transformation methods were 0.96 mm for t2-weighted spin-echo and 1.67 mm for t1-weighted gradient-echo imaging. Maximum deviations were 1.72 mm and 3.06 mm, respectively.

EUS – Fine- Needle Aspiration Biopsy (FNAB in the Diagnosis of Pancreatic Adenocarcinoma: A Review

Directory of Open Access Journals (Sweden)

Kalogeraki Alexandra

2016-03-01

Full Text Available Solid masses of the pancreas represent a variety of benign and malignant neoplasms of the exocrine and endocrine tissues of the pancreas. A tissue diagnosis is often required to direct therapy in the face of uncertain diagnosis or if the patient is not a surgical candidate either due to advanced disease or comorbidities. Endoscopic ultrasound (EUS is a relatively new technology that employs endoscopy and high-frequency ultrasound (US. EUS involves imaging of the pancreatic head and the uncinate from the duodenum and imaging of the body and tail from the stomach. It has been shown to be a highly sensitive method for the detection of pancreatic masses. It is superior to extracorporeal US and computed tomographic (CT scans, especially when the pancreatic tumor is smaller than 2-3 cm. Although EUS is highly sensitive in detecting pancreatic solid masses, its ability to differentiate between inflammatory masses and malignant disease is limited. Endoscopic retrograde cholangiopancreatography (ERCP brushing, CT-guided biopsies, and transabdominal ultrasound (US have been the standard nonsurgical methods for obtaining a tissue diagnosis of pancreatic lesions, but a substantial false-negative rate has been reported. Transabdominal US-guided fine-needle aspiration biopsy (US-FNAB has been used for tissue diagnosis in patients with suspected pancreatic carcinoma. It has been shown to be highly specific, with no false-positive diagnoses. With the advent of curvilinear echoendoscopes, transgastric and transduodenal EUS-FNAB of the pancreas have become a reality EUS with FNAB has revolutionized the ability to diagnose and stage cancers of the gastrointestinal tract and assess the pancreas. Gastrointestinal cancers can be looked at with EUS and their depth of penetration into the intestinal wall can be determined. Any suspicious appearing lymph nodes can be biopsied using EUS/FNAB. The pancreas is another organ that is well visualized with EUS. Abnormalities

Quantitative contrast-enhanced harmonic EUS in differential diagnosis of focal pancreatic masses (with videos)

DEFF Research Database (Denmark)

Săftoiu, Adrian; Vilmann, Peter; Dietrich, Christoph F

2015-01-01

BACKGROUND: The role of EUS with contrast agents can be expanded through the use of time-intensity curve (TIC) analysis and computer-aided interpretation. OBJECTIVE: To validate the use of parameters derived from TIC analysis in an artificial neural network (ANN) classification model designed......-guided FNA (EUS-FNA), TIC analysis, and ANN processing. MAIN OUTCOME MEASUREMENTS: Sensitivity, specificity, positive and negative predictive values (PPV, NPV) for EUS-FNA, CEH-EUS, and the ANN. RESULTS: After excluding all of the recordings that did not meet the technical and procedural criteria, 112 cases...... rise time, mean transit time, and time to peak. For the ANN, sensitivity was 94.64%, specificity 94.44%, PPV 97.24%, and NPV 89.47%. LIMITATIONS: Only PC and CP lesions were included. CONCLUSION: Parameters obtained through TIC analysis can differentiate between PC and CP cases and can be used...

Endoscopic ultrasound-guided transmural drainage of postoperative pancreatic collections.

Science.gov (United States)

Tilara, Amy; Gerdes, Hans; Allen, Peter; Jarnagin, William; Kingham, Peter; Fong, Yuman; DeMatteo, Ronald; D'Angelica, Michael; Schattner, Mark

2014-01-01

Pancreatic leak is a major cause of morbidity after pancreatectomy. Traditionally, peripancreatic fluid collections have been managed by percutaneous or operative drainage. Data for endoscopic ultrasound (EUS)-guided drainage of postoperative fluid collections are limited. Here we report on the safety, efficacy, and timing of EUS-guided drainage of postoperative peripancreatic collections. This is a retrospective review of 31 patients who underwent EUS-guided drainage of fluid collections after pancreatic resection. Technical success was defined as successful transgastric deployment of at least one double pigtail plastic stent. Clinical success was defined as resolution of the fluid collection on follow-up CT scan and resolution of symptoms. Early drainage was defined as initial transmural stent placement within 30 days after surgery. Endoscopic ultrasound-guided drainage was performed effectively with a technical success rate of 100%. Clinical success was achieved in 29 of 31 patients (93%). Nineteen of the 29 patients (65%) had complete resolution of their symptoms and collection with the first endoscopic procedure. Repeat drainage procedures, including some with necrosectomy, were required in the remaining 10 patients, with eventual resolution of collection and symptoms. Two patients who did not achieve durable clinical success required percutaneous drainage by interventional radiology. Seventeen (55%) of 31 patients had successful early drainage completed within 30 days of their operation. Endoscopic ultrasound-guided drainage of fluid collections after pancreatic resection is safe and effective. Early drainage (collections was not associated with increased complications in this series. Copyright © 2014 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

EUS-guided drainage of pancreatic fluid collections using a novel lumen-apposing metal stent on an electrocautery-enhanced delivery system : a large retrospective study (with video)

NARCIS (Netherlands)

Rinninella, Emanuele; Kunda, Rastislav; Dollhopf, Markus; Sanchez-Yague, Andres; Will, Uwe; Tarantino, Ilaria; Gornals Soler, Joan; Ullrich, Sebastian; Meining, Alexander; Esteban, Josè Miguel; Enz, Thomas; Vanbiervliet, Geoffroy; Vleggaar, FP; Attili, Fabia; Larghi, Alberto

2015-01-01

BACKGROUND AND AIMS: A lumen-apposing, self-expanding metal stent incorporated in an electrocautery-enhanced delivery system for EUS-guided drainage of pancreatic fluid collections (PFCs) recently has become available. The aim of this study was to analyze the safety and clinical effectiveness of

Image-guided intracranial cannula placement for awake in vivo microdialysis in nonhuman primates

Science.gov (United States)

Chen, Antong; Bone, Ashleigh; Hines, Catherine D. G.; Dogdas, Belma; Montgomery, Tamara O.; Michener, Maria; Winkelmann, Christopher T.; Ghafurian, Soheil; Lubbers, Laura S.; Renger, John; Bagchi, Ansuman; Uslaner, Jason M.; Johnson, Colena; Zariwala, Hatim A.

2016-03-01

Intracranial microdialysis is used for sampling neurochemicals and large peptides along with their metabolites from the interstitial fluid (ISF) of the brain. The ability to perform this in nonhuman primates (NHP) e.g., rhesus could improve the prediction of pharmacokinetic (PK) and pharmacodynamics (PD) action of drugs in human. However, microdialysis in rhesus brains is not as routinely performed as in rodents. One challenge is that the precise intracranial probe placement in NHP brains is difficult due to the richness of the anatomical structure and the variability of the size and shape of brains across animals. Also, a repeatable and reproducible ISF sampling from the same animal is highly desirable when combined with cognitive behaviors or other longitudinal study end points. Toward that end, we have developed a semi-automatic flexible neurosurgical method employing MR and CT imaging to (a) derive coordinates for permanent guide cannula placement in mid-brain structures and (b) fabricate a customized recording chamber to implant above the skull for enclosing and safeguarding access to the cannula for repeated experiments. In order to place the intracranial guide cannula in each subject, the entry points in the skull and the depth in the brain were derived using co-registered images acquired from MR and CT scans. The anterior/posterior (A/P) and medial-lateral (M/L) rotation in the pose of the animal was corrected in the 3D image to appropriately represent the pose used in the stereotactic frame. An array of implanted fiducial markers was used to transform stereotactic coordinates to the images. The recording chamber was custom fabricated using computer-aided design (CAD), such that it would fit the contours of the individual skull with minimum error. The chamber also helped in guiding the cannula through the entry points down a trajectory into the depth of the brain. We have validated our method in four animals and our results indicate average placement error

Self-aggregation of magnetic semiconductor EuS nanocrystals

International Nuclear Information System (INIS)

Tanaka, Atsushi; Hasegawa, Yasuchika; Kamikubo, Hironari; Kataoka, Mikio; Kawai, Tsuyoshi

2009-01-01

Controlled formation of aggregates having organized structure of cube-shaped EuS nanocrystals is reported. The EuS aggregates in liquid media (methanol) were obtained by means of van der Waals interaction between EuS nanocrystals. The packing structure of the EuS aggregates is characterized with transmission electron microscopy (TEM) and small angle X-ray scattering measurements (SAXS). TEM image indicates the EuS nanocrystals form self-aggregated 2D orthogonal lattice structure. The diffraction peak of (111) of SAXS profile shows that the cube-shaped EuS form 3D cubic superlattice. We successfully demonstrated that the aggregates of cube-shaped EuS nanocrystals formed cubic stacking structure.

Endoscopic Ultrasound-Guided Perirectal Abscess Drainage without Drainage Catheter: A Case Series

Directory of Open Access Journals (Sweden)

Eun Kwang Choi

2017-05-01

Full Text Available A perirectal abscess is a relatively common disease entity that occurs as a postsurgical complication or as a result of various medical conditions. Endoscopic ultrasound (EUS-guided drainage was recently described as a promising alternative treatment. Previous reports have recommended placement of a drainage catheter through the anus for irrigation, which is inconvenient to the patient and carries a risk of accidental dislodgement. We report four cases of perirectal abscess that were successfully treated with only one or two 7 F double pigtail plastic stent placements and without a drainage catheter for irrigation.

Fiducial registration error as a statistical process control metric in image-guided radiotherapy with prostatic markers

International Nuclear Information System (INIS)

Ung, M.N.; Wee, Leonard

2010-01-01

Full text: Portal imaging of implanted fiducial markers has been in use for image-guided radiotherapy (TORT) of prostate cancer, with ample attention to localization accuracy and organ motion. The geometric uncertainties in point-based rigid-body (PBRB) image registration during localization of prostate fiducial markers can be quantified in terms of a fiducial registration error (FRE). Statistical process control charts for individual patients can be designed to identify potentially significant deviation of FRE from expected behaviour. In this study, the aim was to retrospectively apply statistical process control methods to FREs in 34 individuals to identify parameters that may impact on the process stability in image-based localization. A robust procedure for estimating control parameters, control lim its and fixed tolerance levels from a small number of initial observations has been proposed and discussed. Four distinct types of qualitative control chart behavior have been observed. Probable clinical factors leading to IORT process instability are discussed in light of the control chart behaviour. Control charts have been shown to be a useful decision-making tool for detecting potentially out-of control processes on an individual basis. It can sensitively identify potential problems that warrant more detailed investigation in the 10RT of prostate cancer.

Lipiodol as a Fiducial Marker for Image-Guided Radiation Therapy for Bladder Cancer

Energy Technology Data Exchange (ETDEWEB)

Freilich, Jessica M.; Spiess, Philippe E.; Biagioli, Matthew C.; Fernandez, Daniel C.; Shi, Ellen J.; Hunt, Dylan C.; Gupta, Shilpa; Wilder, Richard B., E-mail: richard.wilder@moffitt.org [Moffitt Cancer Center, Tampa, FL (United States)

2014-03-15

Purpose: To evaluate Lipiodol as a liquid, radio-opaque fiducial marker for image-guided radiation therapy (IGRT) for bladder cancer; Materials and Methods: Between 2011 and 2012, 5 clinical T2a-T3b N0 M0 stage II-III bladder cancer patients were treated with maximal transurethral resection of a bladder tumor (TURBT) and image-guided radiation therapy (IGRT) to 64.8 Gy in 36 fractions ± concurrent weekly cisplatin-based or gemcitabine chemotherapy. Ten to 15mL Lipiodol, using 0.5mL per injection, was injected into bladder submucosa circumferentially around the entire periphery of the tumor bed immediately following maximal TURBT. The authors looked at inter-observer variability regarding the size and location of the tumor bed (CTVboost) on computed tomography scans with versus without Lipiodol. Results: Median follow-up was 18 months. Lipiodol was visible on every orthogonal two-dimensional kV portal image throughout the entire, 7-week course of IGRT. There was a trend towards improved inter-observer agreement on the CTVboost with Lipiodol (p = 0.06). In 2 of 5 patients, the tumor bed based upon Lipiodol extended outside a planning target volume that would have been treated with a radiation boost based upon a cystoscopy report and an enhanced computed tomography (CT) scan for staging. There was no toxicity attributable to Lipiodol: Conclusions: Lipiodol constitutes a safe and effective fiducial marker that an urologist can use to demarcate a tumor bed immediately following maximal TURBT. Lipiodol decreases inter-observer variability in the definition of the extent and location of a tumor bed on a treatment planning CT scan for a radiation boost. (author)

Lipiodol as a Fiducial Marker for Image-Guided Radiation Therapy for Bladder Cancer

Directory of Open Access Journals (Sweden)

Jessica M. Freilich

2014-04-01

Full Text Available Purpose To evaluate Lipiodol as a liquid, radio-opaque fiducial marker for image-guided radiation therapy (IGRT for bladder cancer.Materials and Methods Between 2011 and 2012, 5 clinical T2a-T3b N0 M0 stage II-III bladder cancer patients were treated with maximal transurethral resection of a bladder tumor (TURBT and image-guided radiation therapy (IGRT to 64.8 Gy in 36 fractions ± concurrent weekly cisplatin-based or gemcitabine chemotherapy. Ten to 15mL Lipiodol, using 0.5mL per injection, was injected into bladder submucosa circumferentially around the entire periphery of the tumor bed immediately following maximal TURBT. The authors looked at inter-observer variability regarding the size and location of the tumor bed (CTVboost on computed tomography scans with versus without Lipiodol.Results Median follow-up was 18 months. Lipiodol was visible on every orthogonal two-dimensional kV portal image throughout the entire, 7-week course of IGRT. There was a trend towards improved inter-observer agreement on the CTVboost with Lipiodol (p = 0.06. In 2 of 5 patients, the tumor bed based upon Lipiodol extended outside a planning target volume that would have been treated with a radiation boost based upon a cystoscopy report and an enhanced computed tomography (CT scan for staging. There was no toxicity attributable to Lipiodol.Conclusions Lipiodol constitutes a safe and effective fiducial marker that an urologist can use to demarcate a tumor bed immediately following maximal TURBT. Lipiodol decreases inter-observer variability in the definition of the extent and location of a tumor bed on a treatment planning CT scan for a radiation boost.

Fiducial-based registration with a touchable region model.

Science.gov (United States)

Kim, Sungmin; Kazanzides, Peter

2017-02-01

Image-guided surgery requires registration between an image coordinate system and an intraoperative coordinate system that is typically referenced to a tracking device. In fiducial-based registration methods, this is achieved by localizing points (fiducials) in each coordinate system. Often, both localizations are performed manually, first by picking a fiducial point in the image and then by using a hand-held tracked pointer to physically touch the corresponding fiducial on the patient. These manual procedures introduce localization error that is user-dependent and can significantly decrease registration accuracy. Thus, there is a need for a registration method that is tolerant of imprecise fiducial localization in the preoperative and intraoperative phases. We propose the iterative closest touchable point (ICTP) registration framework, which uses model-based localization and a touchable region model. This method consists of three stages: (1) fiducial marker localization in image space, using a fiducial marker model, (2) initial registration with paired-point registration, and (3) fine registration based on the iterative closest point method. We perform phantom experiments with a fiducial marker design that is commonly used in neurosurgery. The results demonstrate that ICTP can provide accuracy improvements compared to the standard paired-point registration method that is widely used for surgical navigation and surgical robot systems, especially in cases where the surgeon introduces large localization errors. The results demonstrate that the proposed method can reduce the effect of the surgeon's localization performance on the accuracy of registration, thereby producing more consistent and less user-dependent registration outcomes.

The Placement Handbook. A Guide for the Competitive Employment of the Handicapped.

Science.gov (United States)

Horn, Adelaide; Drury, Stephen

This handbook stresses those components that are considered peripheral to the placement process but that must precede the actual placement. The philosophy of placement upon which this guide is based appears first. Discussions follow of the basic components of the process of training and placement of handicapped individuals, including a varied…

A new fiducial marker for Image-guided radiotherapy of prostate cancer: Clinical experience

Energy Technology Data Exchange (ETDEWEB)

Carl, Jesper; Nielsen, Jane; Holmberg, Mats; Hoejkjaer Larsen, Erik; Fabrin, Knud; Fisker, Rune V. (Dept. of Medical Physics, Oncology, Aalborg Hospital (Denmark))

2008-08-15

Background. A new fiducial marker for image guided radiotherapy (IGRT) based on a removable prostate stent made of Ni Ti has been developed during two previous clinical feasibility studies. The marker is currently being evaluated for IGRT treatment in a third clinical study. Method. The new marker is used to co-register MR and planning CT scans with high accuracy in the region around the prostate. The co-registered MR-CT volumes are used for delineation of GTV before planning. In each treatment session the IGRT system is used to position the patient before treatment. The IGRT system use a stereo pair of kV images matched to corresponding Digital Reconstructed Radiograms (DRR) from the planning CT scan. The match is done using mutual gray scale information. The pair of DRR's for positioning is created in the IGRT system with a threshold in the Look Up Table (LUT). The resulting match provides the necessary shift in couch coordinates to position the stent with an accuracy of 1-2 mm within the planned position. Results. At the present time 39 patients have received the new marker. Of the 39 one has migrated to the bladder. Deviations of more than 5 mm between CTV outlined on CT and MR are seen in several cases and in anterior-posterior (AP), left-right (LR) and cranial-caudal (CC) directions. Intra-fraction translation movements up to +/- 3 mm are seen as well. As the stent is also clearly visible on images taken with high voltage x-rays using electronic portal images devices (EPID), the positioning has been verified independently of the IGRT system. Discussion. The preliminary result of an on going clinical study of a Ni Ti prostate stent, potentially a new fiducial marker for image guided radiotherapy, looks promising. The risk of migration appears to be much lower compared to previous designs

A new fiducial marker for Image-guided radiotherapy of prostate cancer: clinical experience.

Science.gov (United States)

Carl, Jesper; Nielsen, Jane; Holmberg, Mats; Højkjaer Larsen, Erik; Fabrin, Knud; Fisker, Rune V

2008-01-01

A new fiducial marker for image guided radiotherapy (IGRT) based on a removable prostate stent made of Ni Ti has been developed during two previous clinical feasibility studies. The marker is currently being evaluated for IGRT treatment in a third clinical study. The new marker is used to co-register MR and planning CT scans with high accuracy in the region around the prostate. The co-registered MR-CT volumes are used for delineation of GTV before planning. In each treatment session the IGRT system is used to position the patient before treatment. The IGRT system use a stereo pair of kV images matched to corresponding Digital Reconstructed Radiograms (DRR) from the planning CT scan. The match is done using mutual gray scale information. The pair of DRR's for positioning is created in the IGRT system with a threshold in the Look Up Table (LUT). The resulting match provides the necessary shift in couch coordinates to position the stent with an accuracy of 1-2 mm within the planned position. At the present time 39 patients have received the new marker. Of the 39 one has migrated to the bladder. Deviations of more than 5 mm between CTV outlined on CT and MR are seen in several cases and in anterior-posterior (AP), left-right (LR) and cranial-caudal (CC) directions. Intra-fraction translation movements up to +/- 3 mm are seen as well. As the stent is also clearly visible on images taken with high voltage x-rays using electronic portal images devices (EPID), the positioning has been verified independently of the IGRT system. The preliminary result of an on going clinical study of a Ni Ti prostate stent, potentially a new fiducial marker for image guided radiotherapy, looks promising. The risk of migration appears to be much lower compared to previous designs.

A new fiducial marker for Image-guided radiotherapy of prostate cancer: Clinical experience

International Nuclear Information System (INIS)

Carl, Jesper; Nielsen, Jane; Holmberg, Mats; Hoejkjaer Larsen, Erik; Fabrin, Knud; Fisker, Rune V.

2008-01-01

Background. A new fiducial marker for image guided radiotherapy (IGRT) based on a removable prostate stent made of Ni Ti has been developed during two previous clinical feasibility studies. The marker is currently being evaluated for IGRT treatment in a third clinical study. Method. The new marker is used to co-register MR and planning CT scans with high accuracy in the region around the prostate. The co-registered MR-CT volumes are used for delineation of GTV before planning. In each treatment session the IGRT system is used to position the patient before treatment. The IGRT system use a stereo pair of kV images matched to corresponding Digital Reconstructed Radiograms (DRR) from the planning CT scan. The match is done using mutual gray scale information. The pair of DRR's for positioning is created in the IGRT system with a threshold in the Look Up Table (LUT). The resulting match provides the necessary shift in couch coordinates to position the stent with an accuracy of 1-2 mm within the planned position. Results. At the present time 39 patients have received the new marker. Of the 39 one has migrated to the bladder. Deviations of more than 5 mm between CTV outlined on CT and MR are seen in several cases and in anterior-posterior (AP), left-right (LR) and cranial-caudal (CC) directions. Intra-fraction translation movements up to +/- 3 mm are seen as well. As the stent is also clearly visible on images taken with high voltage x-rays using electronic portal images devices (EPID), the positioning has been verified independently of the IGRT system. Discussion. The preliminary result of an on going clinical study of a Ni Ti prostate stent, potentially a new fiducial marker for image guided radiotherapy, looks promising. The risk of migration appears to be much lower compared to previous designs

Implantation and Stability of Metallic Fiducials Within Pulmonary Lesions

International Nuclear Information System (INIS)

Kupelian, Patrick A.; Forbes, Alan; Willoughby, Twyla R. M.S.; Wallace, Karen; Manon, Rafael R.; Meeks, Sanford L.; Herrera, Luis; Johnston, Alan; Herran, Juan J.

2007-01-01

Purpose: To report and describe implantation techniques and stability of metallic fiducials in lung lesions to be treated with external beam radiotherapy. Methods and Materials: Patients undergoing radiation therapy for small early-stage lung cancer underwent implantation with small metallic markers. Implantation was either transcutaneous under computed tomographic (CT) or fluoroscopic guidance or transbronchial with the superDimension/Bronchus system (radiofrequency signal-based bronchoscopy guidance related to CT images). Results: Implantation was performed transcutaneously in 15 patients and transbronchially in 8 patients. Pneumothorax occurred with eight of the 15 transcutaneous implants, six of which required chest tube placement. None of the patients who underwent transbronchial implantation developed pneumothorax. Successfully inserted markers were all usable during gated image-guided radiotherapy. Marker stability was determined by observing the variation in gross target volume (GTV) centroid relative to the marker on repeated CT scans. Average three-dimensional variation in the GTV center relative to the marker was 2.6 ± 1.3 (SD) mm, and the largest variation along any anatomic axis for any patient was <5 mm. Average GTV volume decrease during the observation period was 34% ± 23%. Gross tumor volumes do not appear to shrink uniformly about the center of the tumor, but rather the tumor shapes deform substantially throughout treatment. Conclusions: Transbronchial marker placement is less invasive than transcutaneous placement, which is associated with high pneumothorax rates. Although marker geometry can be affected by tumor shrinkage, implanted markers are stable within tumors throughout the treatment duration regardless of implantation method

Radiation dose associated with CT-guided drain placement for pediatric patients

Energy Technology Data Exchange (ETDEWEB)

Schwartz, Cody J.; Isaacson, Ari J.; Fordham, Lynn Ansley; Ivanovic, Marija; Dixon, Robert G. [University of North Carolina at Chapel Hill, Department of Radiology, UNC Health Care, Chapel Hill, NC (United States); Taylor, J.B. [University of North Carolina at Chapel Hill, Environment, Health and Safety, Chapel Hill, NC (United States)

2017-05-15

To date, there are limited radiation dose data on CT-guided procedures in pediatric patients. Our goal was to quantify the radiation dose associated with pediatric CT-guided drain placement and follow-up drain evaluations in order to estimate effective dose. We searched the electronic medical record and picture archiving and communication system (PACS) to identify all pediatric (<18 years old) CT-guided drain placements performed between January 2008 and December 2013 at our institution. We compiled patient data and radiation dose information from CT-guided drain placements as well as pre-procedural diagnostic CTs and post-procedural follow-up fluoroscopic abscess catheter injections (sinograms). Then we converted dose-length product, fluoroscopy time and number of acquisitions to effective doses using Monte Carlo simulations and age-appropriate conversion factors based on annual quality-control testing. Fifty-two drainages were identified with mean patient age of 11.0 years (5 weeks to 17 years). Most children had diagnoses of appendicitis (n=23) or inflammatory bowel disease (n=11). Forty-seven patients had diagnostic CTs, with a mean effective dose of 7.3 mSv (range 1.1-25.5 mSv). Drains remained in place for an average of 16.9 days (range 0-75 days), with an average of 0.9 (0-5) sinograms per patient in follow-up. The mean effective dose for all drainages and follow-up exams was 5.3 mSv (0.7-17.1) and 62% (32/52) of the children had effective doses less than 5 mSv. The majority of pediatric patients who have undergone CT-guided drain placements at our institution have received total radiation doses on par with diagnostic ranges. This information could be useful when describing the dose of radiation to parents and providers when CT-guided drain placement is necessary. (orig.)

Radiation dose associated with CT-guided drain placement for pediatric patients

International Nuclear Information System (INIS)

Schwartz, Cody J.; Isaacson, Ari J.; Fordham, Lynn Ansley; Ivanovic, Marija; Dixon, Robert G.; Taylor, J.B.

2017-01-01

To date, there are limited radiation dose data on CT-guided procedures in pediatric patients. Our goal was to quantify the radiation dose associated with pediatric CT-guided drain placement and follow-up drain evaluations in order to estimate effective dose. We searched the electronic medical record and picture archiving and communication system (PACS) to identify all pediatric (<18 years old) CT-guided drain placements performed between January 2008 and December 2013 at our institution. We compiled patient data and radiation dose information from CT-guided drain placements as well as pre-procedural diagnostic CTs and post-procedural follow-up fluoroscopic abscess catheter injections (sinograms). Then we converted dose-length product, fluoroscopy time and number of acquisitions to effective doses using Monte Carlo simulations and age-appropriate conversion factors based on annual quality-control testing. Fifty-two drainages were identified with mean patient age of 11.0 years (5 weeks to 17 years). Most children had diagnoses of appendicitis (n=23) or inflammatory bowel disease (n=11). Forty-seven patients had diagnostic CTs, with a mean effective dose of 7.3 mSv (range 1.1-25.5 mSv). Drains remained in place for an average of 16.9 days (range 0-75 days), with an average of 0.9 (0-5) sinograms per patient in follow-up. The mean effective dose for all drainages and follow-up exams was 5.3 mSv (0.7-17.1) and 62% (32/52) of the children had effective doses less than 5 mSv. The majority of pediatric patients who have undergone CT-guided drain placements at our institution have received total radiation doses on par with diagnostic ranges. This information could be useful when describing the dose of radiation to parents and providers when CT-guided drain placement is necessary. (orig.)

Improvement in Interobserver Accuracy in Delineation of the Lumpectomy Cavity Using Fiducial Markers

International Nuclear Information System (INIS)

Shaikh, Talha; Chen Ting; Khan, Atif; Yue, Ning J.; Kearney, Thomas; Cohler, Alan; Haffty, Bruce G.; Goyal, Sharad

2010-01-01

Purpose: To determine, whether the presence of gold fiducial markers would improve the inter- and intraphysician accuracy in the delineation of the surgical cavity compared with a matched group of patients who did not receive gold fiducial markers in the setting of accelerated partial-breast irradiation (APBI). Methods and Materials: Planning CT images of 22 lumpectomy cavities were reviewed in a cohort of 22 patients; 11 patients received four to six gold fiducial markers placed at the time of surgery. Three physicians categorized the seroma cavity according to cavity visualization score criteria and delineated each of the 22 seroma cavities and the clinical target volume. Distance between centers of mass, percentage overlap, and average surface distance for all patients were assessed. Results: The mean seroma volume was 36.9 cm 3 and 34.2 cm 3 for fiducial patients and non-fiducial patients, respectively (p = ns). Fiducial markers improved the mean cavity visualization score, to 3.6 ± 1.0 from 2.5 ± 1.3 (p < 0.05). The mean distance between centers of mass, average surface distance, and percentage overlap for the seroma and clinical target volume were significantly improved in the fiducial marker patients as compared with the non-fiducial marker patients (p < 0.001). Conclusions: The placement of gold fiducial markers placed at the time of lumpectomy improves interphysician identification and delineation of the seroma cavity and clinical target volume. This has implications in radiotherapy treatment planning for accelerated partial-breast irradiation and for boost after whole-breast irradiation.

Computer guided pre-operative planning and dental implant placement

Directory of Open Access Journals (Sweden)

Dušan Grošelj

2007-05-01

Full Text Available Background: Implants in dentistry are, besides fixed, removable and maxillofacial prosthodontics, one of the reliable possibility to make functional and aesthetic rehabilitation of the edentulism. Surgical and prosthodontic implant complications are often an inattentive consequence of wrong diagnosis, planning, and placement. In this article we present a technique using a highly advanced software program along with a rapid prototyping technology named stereolithography. A planning software for implant placement needs basically the high quality computed tomographic scan of one or both jaws for making accurate preoperative diagnostics and 3D preoperative plan. Later individual drill guide is designed and generated based on both the CT images and the preoperative planning. The patient specific drill guide transfers the virtual planning to the patient’s mouth at time of surgery.Conclusions: The advantages of computer guided implantology are the better prepared surgery with visualisation of critical anatomic structures, assessment of available bone and data about bone quality, increased confidence for the surgeon, deceased operative time, less frequent use of bone grafts, higher quality of collaboration between specialists and prosthetic lab and better communication with patients. Radiographic examination of the operation field for computer guided planning for implant placement is due to high costs justified as the most important information source on the areas to be implanted.

Effects of line fiducial parameters and beamforming on ultrasound calibration

OpenAIRE

Ameri, Golafsoun; Baxter, John S. H.; McLeod, A. Jonathan; Peters, Terry M.; Chen, Elvis C. S.

2017-01-01

Ultrasound (US)-guided interventions are often enhanced via integration with an augmented reality environment, a necessary component of which is US calibration. Calibration requires the segmentation of fiducials, i.e., a phantom, in US images. Fiducial localization error (FLE) can decrease US calibration accuracy, which fundamentally affects the total accuracy of the interventional guidance system. Here, we investigate the effects of US image reconstruction techniques as well as phantom mater...

SU-F-T-660: Evaluating the Benefit of Using Dual-Function Fiducial Markers for In-Situ Delivery of Radiosenistizing Gold Nanoparticles During Image-Guided Radiotherapy

Energy Technology Data Exchange (ETDEWEB)

AlMansour, S; Chin, J; Sajo, E; Ngwa, W [University Massachusetts Lowell, Lowell, MA (United States)

2016-06-15

Purpose: Dual-function fiducials loaded with radiosensitizers, like gold nanoparticles (GNP), offer an innovative approach for ensuring geometric accuracy during image-guided radiotherapy (IGRT) and significantly increasing therapeutic efficacy due to controlled in-situ release of the radiosensitizers. This study retrospectively investigates the dosimetric benefit of using up to two such dual-function fiducial markers instead of traditional single function fiducials during IGRT. Methods: A computational code was developed to investigate the dosimetric benefit for 10 real patient tumor volumes of up to 6.5 cm diameter. The intra-tumoral space-time biodistribution of the GNP was modeled as in previous studies based on Fick’s second law. The corresponding dose-enhancement for each tumor voxel due to the GNP was also calculated for clinical 6MV beam configurations. Various loading concentrations (25–50 mg/g) were studied, as a function of GNP size, to determine potential for clinically significant dose enhancement. The time between initial implantation of dual-function fiducials to the beginning of radiotherapy was assumed to be 14 days as typical for many clinics. Results: A single dual-function fiducial could achieve at least a DEF of 1.2 for patients with tumors less than 1.4 cm diameter after 14 days. Replacing two single function fiducials with dual-function ones at the same locations achieved at least the required minimal DEF for tumors that are 2 cm diameter in 3 patients. The results also revealed dosimetrically better fiducial locations which could enable significant DEF when using one or two dual function fiducials. 2 nm sizes showed the most feasibility. Conclusion: The results highlight the potential of tumor sub-volume radiation boosting using GNP released from fiducials, and the ability to customize the DEF throughout the tumor by using two dual-function fiducials, varying the initial concentration and nanoparticle size. The results demonstrate

SU-F-T-660: Evaluating the Benefit of Using Dual-Function Fiducial Markers for In-Situ Delivery of Radiosenistizing Gold Nanoparticles During Image-Guided Radiotherapy

International Nuclear Information System (INIS)

AlMansour, S; Chin, J; Sajo, E; Ngwa, W

2016-01-01

Purpose: Dual-function fiducials loaded with radiosensitizers, like gold nanoparticles (GNP), offer an innovative approach for ensuring geometric accuracy during image-guided radiotherapy (IGRT) and significantly increasing therapeutic efficacy due to controlled in-situ release of the radiosensitizers. This study retrospectively investigates the dosimetric benefit of using up to two such dual-function fiducial markers instead of traditional single function fiducials during IGRT. Methods: A computational code was developed to investigate the dosimetric benefit for 10 real patient tumor volumes of up to 6.5 cm diameter. The intra-tumoral space-time biodistribution of the GNP was modeled as in previous studies based on Fick’s second law. The corresponding dose-enhancement for each tumor voxel due to the GNP was also calculated for clinical 6MV beam configurations. Various loading concentrations (25–50 mg/g) were studied, as a function of GNP size, to determine potential for clinically significant dose enhancement. The time between initial implantation of dual-function fiducials to the beginning of radiotherapy was assumed to be 14 days as typical for many clinics. Results: A single dual-function fiducial could achieve at least a DEF of 1.2 for patients with tumors less than 1.4 cm diameter after 14 days. Replacing two single function fiducials with dual-function ones at the same locations achieved at least the required minimal DEF for tumors that are 2 cm diameter in 3 patients. The results also revealed dosimetrically better fiducial locations which could enable significant DEF when using one or two dual function fiducials. 2 nm sizes showed the most feasibility. Conclusion: The results highlight the potential of tumor sub-volume radiation boosting using GNP released from fiducials, and the ability to customize the DEF throughout the tumor by using two dual-function fiducials, varying the initial concentration and nanoparticle size. The results demonstrate

Use of guiding sheaths in peroral fluoroscopic gastroduodenal stent placement

International Nuclear Information System (INIS)

Bae, Jae-Ik; Shin, Ji Hoon; Song, Ho-Young; Yoon, Chang Jin; Nam, Deok Ho; Choi, Won-Chan; Lim, Jin-Oh

2005-01-01

Our purpose was to assess the safety and usefulness of guiding sheaths in peroral fluoroscopic gastroduodenal stent placement. Two types of guiding sheath were made from straight polytetrafluoroethylene tubes. Type A was 80 cm in length, 4 mm in outer diameter and 3 mm in inner diameter. Type B was 70 cm in length, 6 mm in outer diameter and 5 mm in inner diameter. The type A sheath was used in 18 patients in whom a catheter-guide wire combination failed to pass through a stricture. The type B sheath was used in 22 patients in whom a stent delivery system failed to pass through the stricture due to loop formation within the gastric lumen. The overall success rate for guiding a catheter-guide wire through a stricture after using the type A sheath was 89%. The overall success rate for passing a stent delivery system through a stricture after using the type B sheath was 100%. All procedures were tolerated by the patients without any significant complications. The guiding sheaths were safe and useful in peroral fluoroscopic gastroduodenal stent placement. (orig.)

Endoscopic Ultrasound-Guided Biliary Drainage

International Nuclear Information System (INIS)

Artifon, Everson L.A.; Ferreira, Fla'vio C.; Sakai, Paulo

2012-01-01

To demonstrate a comprehensive review of published articles regarding endoscopic ultrasound (EUS)-guided biliary drainage. Review of studies regarding EUS-guided biliary drainage including case reports, case series and previous reviews. EUS-guided hepaticogastrostomy, coledochoduodenostomy and choledoantrostomy are advanced biliary and pancreatic endoscopy procedures, and together make up the echo-guided biliary drainage. Hepaticogastrostomy is indicated in cases of hilar obstruction, while the procedure of choice is the coledochoduodenostomy or choledochoantrostomy in distal lesions. Both procedures must be performed only after unsuccessful ERCPs. The indication of these procedures must be made under a multidisciplinary view while sharing information with the patient or legal guardian. Hepaticogastrostomy and coledochoduodenostomy or choledochoantrostomy are feasible when performed by endoscopists with expertise in biliopancreatic endoscopy. Advanced echo-endoscopy should currently be performed under a rigorous protocol in educational institutions.

Endoscopic Ultrasound-Guided Biliary Drainage

Energy Technology Data Exchange (ETDEWEB)

Artifon, Everson L.A.; Ferreira, Fla& #x27; vio C.; Sakai, Paulo [University of Saeo Paulo, Saeo Paulo (Brazil)

2012-02-15

To demonstrate a comprehensive review of published articles regarding endoscopic ultrasound (EUS)-guided biliary drainage. Review of studies regarding EUS-guided biliary drainage including case reports, case series and previous reviews. EUS-guided hepaticogastrostomy, coledochoduodenostomy and choledoantrostomy are advanced biliary and pancreatic endoscopy procedures, and together make up the echo-guided biliary drainage. Hepaticogastrostomy is indicated in cases of hilar obstruction, while the procedure of choice is the coledochoduodenostomy or choledochoantrostomy in distal lesions. Both procedures must be performed only after unsuccessful ERCPs. The indication of these procedures must be made under a multidisciplinary view while sharing information with the patient or legal guardian. Hepaticogastrostomy and coledochoduodenostomy or choledochoantrostomy are feasible when performed by endoscopists with expertise in biliopancreatic endoscopy. Advanced echo-endoscopy should currently be performed under a rigorous protocol in educational institutions.

Alleviating Pancreatic Cancer-Associated Pain Using Endoscopic Ultrasound-Guided Neurolysis

Science.gov (United States)

Takenaka, Mamoru; Kamata, Ken; Yoshikawa, Tomoe; Nakai, Atsushi; Omoto, Shunsuke; Miyata, Takeshi; Yamao, Kentaro; Imai, Hajime; Sakamoto, Hiroki; Kitano, Masayuki; Kudo, Masatoshi

2018-01-01

The most common symptom in patients with advanced pancreatic cancer is abdominal pain. This has traditionally been treated with nonsteroidal anti-inflammatory drugs and opioid analgesics. However, these treatments result in inadequate pain control or drug-related adverse effects in some patients. An alternative pain-relief modality is celiac plexus neurolysis, in which the celiac plexus is chemically ablated. This procedure was performed percutaneously or intraoperatively until 1996, when endoscopic ultrasound (EUS)-guided celiac plexus neurolysis was first described. In this transgastric anterior approach, a neurolytic agent is injected around the celiac trunk under EUS guidance. The procedure gained popularity as a minimally invasive approach and is currently widely used to treat pancreatic cancer-associated pain. We focus on two relatively new techniques of EUS-guided neurolysis: EUS-guided celiac ganglia neurolysis and EUS-guided broad plexus neurolysis, which have been developed to improve efficacy. Although the techniques are safe and effective in general, some serious adverse events including ischemic and infectious complications have been reported as the procedure has gained widespread popularity. We summarize reported clinical outcomes of EUS-guided neurolysis in pancreatic cancer (from the PubMed and Embase databases) with a goal of providing information useful in developing strategies for pancreatic cancer-associated pain alleviation. PMID:29462851

Endoscopic Ultrasonography-Guided Techniques for Accessing and Draining the Biliary System and the Pancreatic Duct.

Science.gov (United States)

Rimbaş, Mihai; Larghi, Alberto

2017-10-01

When endoscopic retrograde cholangiopancreatography (ERCP) fails to decompress the biliary system or the pancreatic duct, endoscopic ultrasonography (EUS)-guided biliary or pancreatic access and drainage can be used. Data show a high success rate and acceptable adverse event rate for EUS-guided biliary drainage. The outcomes of EUS-guided biliary drainage seem equivalent to percutaneous drainage and ERCP, whereas only retrospective studies are available for pancreatic duct drainage. In this article, revision of the technical and clinical status and the current evidence of interventional EUS-guided biliary and pancreatic duct access and drainage are presented. Copyright © 2017 Elsevier Inc. All rights reserved.

Feasibility Study of EUS-NOTES as a Novel Approach for Pancreatic Cancer Staging and Therapy

DEFF Research Database (Denmark)

Săftoiu, Adrian; Bhutani, Manoop S; Vilmann, Peter

2012-01-01

-guided transgastric approach was tested for ease of access to the tail of the pancreas. Gastric wound closure was finally performed in several animals using various commercial and prototype endoscopic accessories. Results: The results showed the ability of EUS-NOTES technology to facilitate a transgastric approach...

Endoscopic Ultrasound-Guided Rendezvous Technique for Failed Biliary Cannulation in Benign and Resectable Malignant Biliary Disorders.

Science.gov (United States)

Shiomi, Hideyuki; Yamao, Kentaro; Hoki, Noriyuki; Hisa, Takeshi; Ogura, Takeshi; Minaga, Kosuke; Masuda, Atsuhiro; Matsumoto, Kazuya; Kato, Hironari; Kamada, Hideki; Goto, Daisuke; Imai, Hajime; Takenaka, Mamoru; Noguchi, Chishio; Nishikiori, Hidefumi; Chiba, Yasutaka; Kutsumi, Hiromu; Kitano, Masayuki

2018-03-01

Endoscopic ultrasound-guided rendezvous technique (EUS-RV) has emerged as an effective salvage method for unsuccessful biliary cannulation. However, its application for benign and resectable malignant biliary disorders has not been fully evaluated. To assess the efficacy and safety of EUS-RV for benign and resectable malignant biliary disorders. This was a multicenter prospective study from 12 Japanese referral centers. Patients who underwent EUS-RV after failed biliary cannulation for biliary disorder were candidates for this study. Inclusion criteria were unsuccessful biliary cannulation for therapeutic endoscopic retrograde cholangiopancreatography with benign and potentially resectable malignant biliary obstruction. Exclusion criteria included unresectable malignant biliary obstruction, inaccessible papillae due to surgically altered upper gastrointestinal anatomy or duodenal stricture, and previous sphincterotomy and/or biliary stent placement. The primary outcome was the technical success rate of biliary cannulation; procedure time, adverse events, and clinical outcomes were secondary outcomes. Twenty patients were prospectively enrolled. The overall technical success rate and median procedure time were 85% and 33 min, respectively. Guidewire manipulation using a 4-Fr tapered tip catheter contributed to the success in advancing the guidewire into the duodenum. Adverse events were identified in 15% patients, including 2 with biliary peritonitis and 1 mild pancreatitis. EUS-RV did not affect surgical maneuvers or complications associated with surgery, or postoperative course. EUS-RV may be a safe and feasible salvage method for unsuccessful biliary cannulation for benign or resectable malignant biliary disorders. Use of a 4-Fr tapered tip catheter may improve the overall EUS-RV success rate.

Advanced Placement Mathematics Calculus, Grade 12 Curriculum Guide.

Science.gov (United States)

Scharf, John; And Others

This document is a guide to the advanced placement program in calculus for grade 12 in the city schools in Warren, Ohio. The program covers analytic geometry, differential and integral calculus of algebraic functions, elementary transcendental functions, and applications of differentiation and integration. The philosophy and aims of the program…

Assessment of prostatic fiducial marker introduction: patient morbidity, staff satisfaction and improved treatment field placement

International Nuclear Information System (INIS)

Brown, Simon; Lehman, Margot; Ferrari-Anderson, Janet; Glyde, Alan; Burmeister, Elizabeth; Nicol, David

2011-01-01

Increased accuracy when using fiducial markers for prostate localisation is well documented. This project aimed to establish the improvement in accuracy when using gold markers for daily prostate localisation, to assess patient satisfaction and morbidity from the transrectal implantation of gold seed markers and establish staff attitudes towards the newly introduced processes. Twenty patients with prostate cancer had three gold seeds implanted into the base, apex and central zone of the prostate transrectally using ultrasound guidance. Surveys were conducted to assess staff and patient satisfaction with the process of gold seed localisation. The gold markers were used to localise the prostate on a daily basis using megavoltage electronic portal imaging. Measurements were taken to establish the increase in accuracy when using gold fiducial markers compared with using the surrounding bony anatomy. Inter-fraction motion (1 standard deviation (SD)) of the fiducial markers was 2.20, 4.28 and 4.27 mm in the LR, SI and AP directions, respectively. Intra-fraction prostate motion (1 SD) was measured as 0.8 mm LR, 1.1 mm SI and 2.0 mm AP. The patient survey showed that the insertion and associated side effects were acceptable, with 5% of patients stating that the seed insertion was worse than the prostate biopsy, and 23.1% of patients experienced short duration (1–2 days) haematuria. The staff survey showed that daily online image guidance was achievable without affecting patient throughput. Thirty percent of treatment staff believed that performing online daily localisation did not add any extra time to a standard treatment, and the remaining 70% thought that the added time was minimal (2–4 min). Gold fiducial markers are an accurate, reliable and tolerable method of daily prostate localisation.

Line fiducial material and thickness considerations for ultrasound calibration

Science.gov (United States)

Ameri, Golafsoun; McLeod, A. J.; Baxter, John S. H.; Chen, Elvis C. S.; Peters, Terry M.

2015-03-01

Ultrasound calibration is a necessary procedure in many image-guided interventions, relating the position of tools and anatomical structures in the ultrasound image to a common coordinate system. This is a necessary component of augmented reality environments in image-guided interventions as it allows for a 3D visualization where other surgical tools outside the imaging plane can be found. Accuracy of ultrasound calibration fundamentally affects the total accuracy of this interventional guidance system. Many ultrasound calibration procedures have been proposed based on a variety of phantom materials and geometries. These differences lead to differences in representation of the phantom on the ultrasound image which subsequently affect the ability to accurately and automatically segment the phantom. For example, taut wires are commonly used as line fiducials in ultrasound calibration. However, at large depths or oblique angles, the fiducials appear blurred and smeared in ultrasound images making it hard to localize their cross-section with the ultrasound image plane. Intuitively, larger diameter phantoms with lower echogenicity are more accurately segmented in ultrasound images in comparison to highly reflective thin phantoms. In this work, an evaluation of a variety of calibration phantoms with different geometrical and material properties for the phantomless calibration procedure was performed. The phantoms used in this study include braided wire, plastic straws, and polyvinyl alcohol cryogel tubes with different diameters. Conventional B-mode and synthetic aperture images of the phantoms at different positions were obtained. The phantoms were automatically segmented from the ultrasound images using an ellipse fitting algorithm, the centroid of which is subsequently used as a fiducial for calibration. Calibration accuracy was evaluated for these procedures based on the leave-one-out target registration error. It was shown that larger diameter phantoms with lower

Preliminary Results of Emergency Computed Tomography-Guided Ventricular Drain Placement-Precision for the Most Difficult Cases.

Science.gov (United States)

Nowacki, Andreas; Wagner, Franca; Söll, Nicole; Hakim, Arsany; Beck, Jürgen; Raabe, Andreas; Z'Graggen, Werner J

2018-04-05

External ventricular drainage (EVD) catheter placement is one of the most commonly performed neurosurgical procedures. The study's objective was to compare a computed tomography (CT) bolt scan-guided approach for the placement of EVDs with conventional landmark-based insertion. In this retrospective case-control study, we analyzed patients undergoing bolt-kit EVD catheter placement, either CT-guided or landmark-based, between 2013 and 2016. The CT bolt scan-guided approach was based on a dose-reduced CT scan after bolt fixation with immediate image reconstruction along the axis of the bolt to evaluate the putative insertion axis. If needed, angulation of the bolt was corrected and the procedure repeated before the catheter was inserted. Primary endpoint was the accuracy of insertion. Secondary endpoints were the overall number of attempts, duration of intervention, complication rates, and cumulative radiation dose. In total, 34 patients were included in the final analysis. In the group undergoing CT-guided placement, the average ventricle width was significantly smaller (P = 0.04) and average midline shift significantly more pronounced (P = 0.01). CT-guided placement resulted in correct positioning of the catheter in the ipsilateral frontal horn in all 100% of the cases compared with landmark-guided insertion (63%; P = 0.01). Application of the CT-guided approach increased the number of total CT scans (3.6 ± 1.9) and the overall radiation dose (3.34 ± 1.61 mSv) compared with the freehand insertion group (1.84 ± 2.0 mSv and 1.55 ± 1.66 mSv). No differences were found for the other secondary outcome parameters. CT-guided bolt-kit EVD catheter placement is feasible and accurate in the most difficult cases. Copyright © 2018 Elsevier Inc. All rights reserved.

Ultrasound-guided supra-acetabular pin placement in pelvic external fixation: description of a surgical technique and results.

Science.gov (United States)

Chana-Rodríguez, Francisco; Cuervas-Mons, Manuel; Rojo-Manaute, José; Mora, Félix; Arnal, Juan; Vaquero-Martín, Javier

2017-11-01

Pelvic fracture in trauma patients can lead to hemodynamic instability. External fixation is a treatment capable of stabilizing these injuries in the context of damage control surgery. Supra-acetabular pin offers the greater biomechanical stability but requires the use of intraoperative fluoroscopy. The aim of this study was to analyze our results for an ultrasound-guided supra-acetabular pinning. Cross-sectional study with cadaveric specimens. Ultrasound-guided pin placement assessed by fluoroscopy and dissection. Fourteen ultrasound-guided supra-acetabular pins were placed in seven cadaveric specimens. Excellent placement in all cases, evaluated with radiological control. Good qualitative bone fixation after dissection. One femoral cutaneous nerve was not found during anatomic dissection and was assumed injured. Ultrasound-guided supra-acetabular pin placement is a feasible and effective technique. Our study indicates that pin placement without intraoperative fluoroscopy is feasible without compromising the reliability of its placement. © 2017 Elsevier Ltd. All rights reserved.

Real time elastography endoscopic ultrasound (RTE-EUS), a comprehensive review

Energy Technology Data Exchange (ETDEWEB)

Dietrich, C.F., E-mail: christoph.dietrich@ckbm.de [Med. Klinik 2, Caritas-Krankenhaus Bad Mergentheim (Germany); Department of Gastroenterology, Research Center of Gastroenterology and Hepatology, University of Medicine and Pharmacy of Craiova (Romania); Klinik für Innere Medizin, Krankenhaus Märkisch Oderland (Germany); Săftoiu, A.; Jenssen, C. [Med. Klinik 2, Caritas-Krankenhaus Bad Mergentheim (Germany); Department of Gastroenterology, Research Center of Gastroenterology and Hepatology, University of Medicine and Pharmacy of Craiova (Romania); Klinik für Innere Medizin, Krankenhaus Märkisch Oderland (Germany)

2014-03-15

Real-time elastography (RTE) performed during endoscopic ultrasound (EUS) is a relatively new technique which allows the evaluation of tissue stiffness, with the intent of better characterising lesions during EUS examinations. The aim of this comprehensive review was to describe the technique of RTE-EUS, as well as the clinical applications, including the study of pancreatic lesions, but also hepatobiliary, gastrointestinal (GI) tract pathology (including anal canal), lymph nodes, adrenal glands, lung and mediastinum, as well as urogenital applications. One of the advantages of the RTE-EUS technique is especially the possibility to be used in various locations accessible from the GI tract. Future developments are also briefly discussed, as elastography is a tissue characterising technique that will certainly not replace biopsy, but will rather be an adjunct during EUS examinations, due to its ease of use and low cost.

Real time elastography endoscopic ultrasound (RTE-EUS), a comprehensive review

International Nuclear Information System (INIS)

Dietrich, C.F.; Săftoiu, A.; Jenssen, C.

2014-01-01

Real-time elastography (RTE) performed during endoscopic ultrasound (EUS) is a relatively new technique which allows the evaluation of tissue stiffness, with the intent of better characterising lesions during EUS examinations. The aim of this comprehensive review was to describe the technique of RTE-EUS, as well as the clinical applications, including the study of pancreatic lesions, but also hepatobiliary, gastrointestinal (GI) tract pathology (including anal canal), lymph nodes, adrenal glands, lung and mediastinum, as well as urogenital applications. One of the advantages of the RTE-EUS technique is especially the possibility to be used in various locations accessible from the GI tract. Future developments are also briefly discussed, as elastography is a tissue characterising technique that will certainly not replace biopsy, but will rather be an adjunct during EUS examinations, due to its ease of use and low cost

A fiducial detection algorithm for real-time image guided IMRT based on simultaneous MV and kV imaging.

Science.gov (United States)

Mao, Weihua; Riaz, Nadeem; Lee, Louis; Wiersma, Rodney; Xing, Lei

2008-08-01

The advantage of highly conformal dose techniques such as 3DCRT and IMRT is limited by intrafraction organ motion. A new approach to gain near real-time 3D positions of internally implanted fiducial markers is to analyze simultaneous onboard kV beam and treatment MV beam images (from fluoroscopic or electronic portal image devices). Before we can use this real-time image guidance for clinical 3DCRT and IMRT treatments, four outstanding issues need to be addressed. (1) How will fiducial motion blur the image and hinder tracking fiducials? kV and MV images are acquired while the tumor is moving at various speeds. We find that a fiducial can be successfully detected at a maximum linear speed of 1.6 cm/s. (2) How does MV beam scattering affect kV imaging? We investigate this by varying MV field size and kV source to imager distance, and find that common treatment MV beams do not hinder fiducial detection in simultaneous kV images. (3) How can one detect fiducials on images from 3DCRT and IMRT treatment beams when the MV fields are modified by a multileaf collimator (MLC)? The presented analysis is capable of segmenting a MV field from the blocking MLC and detecting visible fiducials. This enables the calculation of nearly real-time 3D positions of markers during a real treatment. (4) Is the analysis fast enough to track fiducials in nearly real time? Multiple methods are adopted to predict marker positions and reduce search regions. The average detection time per frame for three markers in a 1024 x 768 image was reduced to 0.1 s or less. Solving these four issues paves the way to tracking moving fiducial markers throughout a 3DCRT or IMRT treatment. Altogether, these four studies demonstrate that our algorithm can track fiducials in real time, on degraded kV images (MV scatter), in rapidly moving tumors (fiducial blurring), and even provide useful information in the case when some fiducials are blocked from view by the MLC. This technique can provide a gating signal or

Quantification of MRI visibility and artifacts at 3T of liquid fiducial marker in a pancreas tissue-mimicking phantom

DEFF Research Database (Denmark)

Schneider, Sergej; Jølck, Rasmus Irming; Troost, Esther Gera Cornelia

2018-01-01

Purpose: X-ray-based position verification of the target volume in image-guided radiation therapy (IGRT) of patients with pancreatic ductal adenocarcinoma (PDAC) is currently performed on solid fiducial markers that are implanted under endoscopic ultrasonography. A new biodegradable liquid fiduci...

Endoscopic Ultrasound Guided Rendezvous Drainage of Biliary Obstruction Using a New Flexible 19-Gauge Fine Needle Aspiration Needle.

Science.gov (United States)

Tang, Zhouwen; Igbinomwanhia, Efehi; Elhanafi, Sherif; Othman, Mohamed O

2016-01-01

Background and Aim. A successful endoscopic ultrasound guided rendezvous (EUS-RV) biliary drainage is dependent on accurate puncture of the bile duct and precise guide wire manipulation across the ampulla of Vater. We aim to study the feasibility of using a flexible 19-gauge fine aspiration needle in the performance of EUS-RV biliary drainage. Method. This is a retrospective case series of EUS-RV biliary drainage procedures at a single center. Patients who failed ERCP during the same session for benign or malignant biliary obstruction underwent EUS-RV using a flexible, nitinol covered, 19-gauge needle for biliary access and guide wire manipulation. Result. 24 patients underwent EUS-RV biliary drainage via extrahepatic access while 1 attempt was via intrahepatic access. The technical success rate was 80%, including 83.3% of cases via extrahepatic access. There was no significant difference in success rate of inpatient and outpatient procedures, benign or malignant indications, or type of guide wire used. Adverse events included mild pancreatitis (3 patients) and cholangitis (1 patient). Conclusion. A flexible 19-gauge needle for biliary access can be safe and effective when used to perform EUS-RV biliary drainage. Direct comparison between the nitinol needle and conventional metal needles in the performance of EUS guided biliary drainage is needed.

Virtually fabricated guide for placement of the C-tube miniplate.

Science.gov (United States)

Paek, Janghyun; Jeong, Do-Min; Kim, Yong; Kim, Seong-Hun; Chung, Kyu-Rhim; Nelson, Gerald

2014-05-01

This paper introduces a virtually planned and stereolithographically fabricated guiding system that will allow the clinician to plan carefully for the best location of the device and to achieve an accurate position without complications. The scanned data from preoperative dental casts were edited to obtain preoperative 3-dimensional (3D) virtual models of the dentition. After the 3D virtual models were repositioned, the 3D virtual surgical guide was fabricated. A surgical guide was created onscreen, and then these virtual guides were materialized into real ones using the stereolithographic technique. Whereas the previously described guide required laboratory work to be performed by the orthodontist, our technique is more convenient because the laboratory work is done remotely by computer-aided design/computer-aided manufacturing technology. Because the miniplate is firmly held in place as the patient holds his or her mandibular teeth against the occlusal pad of the surgical guide, there is no risk that the miniscrews can slide on the bone surface during placement. The software program (2.5-dimensional software) in this study combines 2-dimensional cephalograms with 3D virtual dental models. This software is an effective and efficient alternative to 3D software when 3D computed tomography data are not available. To confidently and safely place a miniplate with screw fixation, a simple customized guide for an orthodontic miniplate was introduced. The use of a custom-made, rigid guide when placing miniplates will minimize complications such as vertical mislocation or slippage of the miniplate during placement. Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Novel needle guide reduces time to perform ultrasound-guided femoral nerve catheter placement: A randomised controlled trial.

Science.gov (United States)

Turan, Alparslan; Babazade, Rovnat; Elsharkawy, Hesham; Esa, Wael Ali Sakr; Maheshwari, Kamal; Farag, Ehab; Zimmerman, Nicole M; Soliman, Loran Mounir; Sessler, Daniel I

2017-03-01

Ultrasound-guided nerve blocks have become the standard when performing regional nerve blocks in anaesthesia. Infiniti Plus (CIVCO Medical Solutions, Kalona, Iowa, USA) is a needle guide that has been recently developed to help clinicians in performing ultrasound-guided nerve blocks. We tested the hypothesis that femoral nerve catheter placement carried out with the Infiniti Plus needle guide will be quicker to perform than without the Infiniti Plus. Secondary aims were to assess whether the Infiniti Plus needle guide decreased the number of block attempts and also whether it improved needle visibility. A randomised, controlled trial. Cleveland Clinic, Cleveland, Ohio, USA. We enrolled adult patients having elective total knee arthroplasty with a femoral nerve block and femoral nerve catheter. Patients, who were pregnant or those who had preexisting neuropathy involving the surgical limb, coagulopathy, infection at the block site or allergy to local anaesthetics were excluded. Patients were randomised into two groups to receive the ultrasound-guided femoral nerve catheter placement with or without the Infiniti Plus needle guide. The time taken to place the femoral nerve catheter, the number of attempts, the success rate and needle visibility were recorded. We used an overall α of 0.05 for both the primary and secondary analyses; the secondary analyses were Bonferroni corrected to control for multiple comparisons. The median (interquartile range Q1 to Q3) time to perform the femoral nerve catheter placement was 118 (100 to 150) s with Infiniti Plus and 177 (130 to 236) s without Infiniti Plus. Infiniti Plus significantly reduced the time spent performing femoral nerve catheterisation, with estimated ratio of means [(95% confidence interval), P value] of 0.67 [(0.60 to 0.75), P Infiniti Plus compared with no Infiniti Plus. However, Infiniti Plus had no effect on the odds of a successful femoral nerve catheter placement, number of attempts or percentage of perfect

Preparation of EuSe nanoparticles from Eu(III) complex containing selenides

International Nuclear Information System (INIS)

Adachi, Taka-aki; Tanaka, Atsushi; Hasegawa, Yasuchika; Kawai, Tsuyoshi

2008-01-01

The EuSe nanoparticles were prepared by the thermal reduction of Europium nitrate with new organic selenium compound, tetraphenylphosphonium diphenylphosphinediselenide (PPh 4 )(Se 2 P(C 6 H 5 ) 2 ), for the first time. EuSe nanoparticles were identified by the X-ray diffraction (XRD), the transmission electron microscope (TEM) and the energy dispersive X-ray spectroscopy (EDX) measurements. The average size of the EuSe nanoparticles was found to be 19 nm. The energy gap in EuSe nanoparticles of 19 nm was estimated by edge of absorption band, giving the energy gap of 1.86 eV

Diagnostic accuracy of endoscopic ultrasonography (EUS) for the preoperative locoregional staging of primary gastric cancer.

Science.gov (United States)

Mocellin, Simone; Pasquali, Sandro

2015-02-06

accuracy can be considered clinically useful to guide physicians in the locoregional staging of people with gastric cancer. However, it should be noted that between-study heterogeneity was not negligible: unfortunately, we could not identify any consistent source of the observed heterogeneity. Therefore, all accuracy measures reported in the present work and summarizing the available evidence should be interpreted cautiously. Moreover, we must emphasize that the analysis of positive and negative likelihood values revealed that EUS diagnostic performance cannot be considered optimal either for disease confirmation or for exclusion, especially for the ability of EUS to distinguish T1a (mucosal) versus T1b (submucosal) cancers and positive versus negative lymph node status. By analyzing the data from the largest series ever considered, we found that the diagnostic accuracy of EUS might be considered clinically useful to guide physicians in the locoregional staging of people with gastric carcinoma. However, the heterogeneity of the results warrants special caution, as well as further investigation for the identification of factors influencing the outcome of this diagnostic tool. Moreover, physicians should be warned that EUS performance is lower in diagnosing superficial tumors (T1a versus T1b) and lymph node status (positive versus negative). Overall, we observed large heterogeneity and its source needs to be understood before any definitive conclusion can be drawn about the use of EUS can be proposed in routine clinical settings.

Electron-spin polarization in tunnel junctions with ferromagnetic EuS barriers

International Nuclear Information System (INIS)

Hao, X.; Moodera, J.S.; Meservey, R.

1989-01-01

The authors report here spin-polarized tunneling experiments using non-ferromagnetic electrodes and ferromagnetic EuS barriers. Because of the conduction band in EuS splits into spin-up and spin-down subbands when the temperature is below 16.7 K, the Curie temperature of EuS, the tunnel barrier for electrons with different spin directions is different, therefore giving rise to tunnel current polarization. The spin-filter effect, as it may be called, was observed earlier, directly or indirectly, by several groups: Esaki et al. made a tunneling study on junctions having EuS and EuSe barriers; Thompson et al. studied Schottky barrier tunneling between In and doped EuS; Muller et al. and Kisker et al. performed electron field emission experiments on EuS-coated tungsten tips. The field emission experiments gave a maximum polarization of (89 + 7)% for the emitted electrons. Although the previous tunneling studies did not directly show electron polarization, their results were explained by the same spin- filter effect. This work uses the spin-polarized tunneling technique to show directly that tunnel current is indeed polarized and polarization can be as high as 85%

Quantification and comparison of visibility and image artifacts of a new liquid fiducial marker in a lung phantom for image-guided radiation therapy

DEFF Research Database (Denmark)

Rydhög, Jonas Scherman; Jølck, Rasmus Irming; Andresen, Thomas Lars

2015-01-01

fiducial marker, four solid fiducial markers, and one existing liquid fiducial marker. Additionally, the image artifacts produced on computer tomography (CT) and cone-beam CT (CBCT) of all fiducial markers were quantified. Results : The authors found that the new liquid fiducial marker with the highest...... concentration of the radio-opaque component had a CNR > 2.05 for 62/63 exposures, which compared favorably to the existing solid fiducial markers and to the existing liquid fiducial marker evaluated. On CT and CBCT, the new liquid fiducial marker with the highest concentration produced lower streaking index...

Impact of endoscopic ultrasonography (EUS) on surgical decision-making in upper gastrointestinal tract cancer

DEFF Research Database (Denmark)

Mortensen, Michael Bau; Edwin, B; Hünerbein, M

2007-01-01

BACKGROUND: Endoscopic ultrasonography (EUS) is an integrated part of the pretherapeutic evaluation program for patients with upper gastrointestinal (GI) tract cancer. Whether the clinical impact of EUS differs between surgeons from different countries is unknown. The same applies to the potential...... clinical influence of EUS misinterpretations. The aim of this study was to evaluate the interobserver agreement on predefined treatment strategies between surgeons from four different countries, with and without EUS, and to evaluate the clinical consequences of EUS misinterpretations. METHODS: One hundred...... patients with upper GI tract cancer were randomly selected from all upper GI tract cancer patients treated at Odense University Hospital between 1997 and 2000. Based on patient records and EUS database results, a case story was created with and without the EUS result for each patient. Four surgeons were...

Intraprostatic fiducials for image guidance: Workflow implications in a single linac department

International Nuclear Information System (INIS)

Middleton, Mark; See, Andrew; Rolfo, Aldo; Medwell, Steve; Joon, Michael Lim; Joon, Daryl Lim; Martin, Jarad; Khoo, Vincent

2008-01-01

Purpose: To assess the accuracy and implications on workflow of an online correction electronic portal imaging (EPI) protocol utilising bony anatomy in the online environment and an assessment of three implanted gold seed fiducial markers in the offline environment. This paper summarises an initial trial to establish the range of systematic and random errors present in patient set-up for both bony anatomy and fiducial markers, and to calculate optimal clinical target volume (CTV) to planning target volume (PTV) margins. The impact of the introduction of such a technique was also assessed in terms of impact on workflow and resource management in a single machine unit (SMU). Methods and materials: Pre treatment electronic portal images (EPIs) were acquired and bony anatomy was matched with CT derived digitally reconstructed radiographs (DRRs). Intervention in field placement was made if field placement fell outside the range of 4 mm on any of the orthogonal axes. In the offline environment the position of the implanted gold seed fiducials was aligned with that of the DRRs. An analysis of set-up error, total error and internal organ motion was then undertaken, with full statistical analysis of systematic and random errors. Results: Eleven patients completed treatment as specified, with 1006 EPIs available for analysis. Treatment times were in the order of 10.4 min. Set-up errors were in the order of 2.7 mm right-left, 2.4 mm sup-inf and 1.6 mm ant-pst. These were reduced to 1.2 mm, 0.7 mm and 0.9 mm respectively utilising an online correction protocol. However there was minimal impact on total error and internal organ motion. Using the data obtained in both the online and offline environments optimal CTV-PTV margins were calculated for correcting to bone, correcting to gold seed fiducials and also the possibility of EPI malfunction. Conclusions: Daily targeting of the prostate is both technically feasible and can be carried out in an efficient and accurate manner. An

CT-guided procedures: evaluation of a phantom system to teach accurate needle placement

International Nuclear Information System (INIS)

Dimmick, S.; Jones, M.; Challen, J.; Iedema, J.; Wattuhewa, U.; Coucher, J.

2007-01-01

Aim: To evaluate the use of a phantom system to help teach the basic techniques of accurate CT-guided needle placement, thereby avoiding the risks associated with teaching on patients. Materials and Methods: Gelatine phantoms with five, 1.9 cm embedded spherical wooden targets were constructed. Four trainee operators performed 15 simulated biopsy procedures on the targets (series one) and repeated identical procedures 2 weeks later (series two). Statistical analysis of accuracy of needle placement and subject confidence were performed. Results: Significant sequential improvement in axial plane angular error was noted with the average error decreasing by 0.33 degrees after every five procedures performed (95% CI: -0.58 to -0.08, p = 0.01). Operator confidence indicated significant improvement both within each series and from series one to series two (95% CI: 0.08 to 1.17, p = 0.025 and 95% CI: 0.00 to 0.58, p = 0.05) respectively. However, variability in operator performance made statistically significant improvement in other variables unproven. Conclusion: Despite the study comprising a relatively small number of participants and procedures, it clearly demonstrated the effectiveness of teaching operators to perform CT-guided procedures using a phantom system. Needle placement accuracy significantly improved, with a reduction in axial angular error, and improved operator confidence without the risks associated with training on patients. Three of the operators in this study had never performed a CT-guided procedure previously, and their proficiency, after a relatively short but intense period of training, was impressive. The use of phantoms should be considered routinely for basic training of CT-guided needle placement

Multicenter randomized controlled trial comparing the performance of 22 gauge versus 25 gauge EUS-FNA needles in solid masses

DEFF Research Database (Denmark)

Vilmann, Peter; S?ftoiu, Adrian; Hollerbach, Stephan

2013-01-01

Few randomized studies have assessed the clinical performance of 25-gauge (25G) needles compared with 22-gauge (22G) needles during endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) biopsy of intra-abdominal lesions. We aimed to compare the diagnostic yield, as well as performance...

Accuracy of EUS for estimating the depth of tumor invasion and for diagnosing lymph node metastasis and recurrence in patients with m3 and sm esophageal carcinomas

International Nuclear Information System (INIS)

Arima, Miwako; Tada, Masahiro; Tanaka, Youichi; Arima, Hideaki

2006-01-01

Esophagus-preserving therapy has been increasingly used to treat esophageal cancer invading the m 3 and sm, thereby avoiding radical surgery. However, many problems remain to be solved, including the diagnosis of lymph node metastasis and recurrence and the assessment of long-term outcomes. We studied 132 patients who had esophageal cancer with m 3 and sm invasion. Clinical course after esophagus-preserving therapy, and the accuracy and roles of endoscopic ultrasonography (EUS) for diagnosing the depth of tumor invasion, lymph node metastasis, and recurrence were assessed. EUS can be used to examine the cervical, thoracic, and abdominal regions, without being affected by heat beats. Therefore, EUS can more clearly depict lymph nodes than CT or US. The accuracy of EUS was 86.4% for estimating the depth of tumor invasion and 82% for diagnosing lymph node metastasis. All cases of nodal recurrence were diagnosed by EUS. Among patients who received chemoradiotherapy, enlarged lymph nodes often appeared around 3 years after treatment, and recurrence was diagnosed slightly later than that in patients who underwent endoscopic mucosal resection. Endoscopic ultrasound-guided fine-needle aspiration biopsy was sometimes performed to determine the treatment policy. Patients who receive chemoradiotherapy should undergo regular long-term follow-up by CT, US, and EUS. EUS is essential for the earlier detection of recurrence. (author)

Effects of line fiducial parameters and beamforming on ultrasound calibration.

Science.gov (United States)

Ameri, Golafsoun; Baxter, John S H; McLeod, A Jonathan; Peters, Terry M; Chen, Elvis C S

2017-01-01

Ultrasound (US)-guided interventions are often enhanced via integration with an augmented reality environment, a necessary component of which is US calibration. Calibration requires the segmentation of fiducials, i.e., a phantom, in US images. Fiducial localization error (FLE) can decrease US calibration accuracy, which fundamentally affects the total accuracy of the interventional guidance system. Here, we investigate the effects of US image reconstruction techniques as well as phantom material and geometry on US calibration. It was shown that the FLE was reduced by 29% with synthetic transmit aperture imaging compared with conventional B-mode imaging in a Z-bar calibration, resulting in a 10% reduction of calibration error. In addition, an evaluation of a variety of calibration phantoms with different geometrical and material properties was performed. The phantoms included braided wire, plastic straws, and polyvinyl alcohol cryogel tubes with different diameters. It was shown that these properties have a significant effect on calibration error, which is a variable based on US beamforming techniques. These results would have important implications for calibration procedures and their feasibility in the context of image-guided procedures.

Fiducial inference - A Neyman-Pearson interpretation

NARCIS (Netherlands)

Salome, D; VonderLinden, W; Dose,; Fischer, R; Preuss, R

1999-01-01

Fisher's fiducial argument is a tool for deriving inferences in the form of a probability distribution on the parameter space, not based on Bayes's Theorem. Lindley established that in exceptional situations fiducial inferences coincide with posterior distributions; in the other situations fiducial

Preoperative noninvasive EUS evaluation in patients with esophageal cancer considered for esophagectomy.

Science.gov (United States)

Gheorghe, Cristian; Stanescu, Codrut; Gheorghe, Liana; Bancila, Ion; Herlea, Vlad; Becheanu, Gabriel; Voinea, Daniela; Iacob, Razvan; Lupescu, Ioana; Anghel, Rodica; Croitoru, Adina; Popescu, Irinel

2006-06-01

Worldwide, esophageal cancer ranks fifth in the mortality rate regarding tumor locations. EUS is an essential tool in the evaluation of these patients allowing accurate staging and permitting stratified treatment options. AIM. We have studied prospectively the impact of EUS in the evaluation and decision for therapy of patients with esophageal cancer diagnosed in our center. From March 2001 through March 2006, 220 patients were hospitalized at the Center of Gastroenterology and Hepatology, Fundeni Clinical Institute, with the diagnosis of esophageal cancer. Out of the 220 patients, 41 patients, with no major comorbidities contraindicating esophagectomy already having been screened by abdominal and thoracic CT to disclose distant metastases, had EUS with the definite purpose of staging esophageal carcinoma and selecting adequate therapy. Assuming that without preoperative staging by EUS, all 41 patients in the study group would have been offered surgical treatment, we evaluated the number of patients and the modality in which EUS resulted in changes to the therapeutic plan. Depth of invasion was recorded for the 41 patients as follows: T1 in 2 patients (4.9%), T2 in 6 patients (14.6%), T3 in 24 patients (58.5%), and T4 in 10 patients (22%). Regional lymph node (N) status as determined by EUS criteria was as follows: N0 in 7 patients (17%) and N1 in 34 patients (83%). Assessment of distant metastases (M) was recorded showing 4 patients with celiac axis lymph nodes metastases (M1). Preoperative EUS staging changed the decision for surgery in 18 of 41 patients (44%) (p<0.0001) and allowed primary esophagectomy in only 6 patients (15%) (p<0.0001). Compared to histopathology, the overall accuracy of EUS staging for pT1 and pT2 was 80% for staging pT3 and pT4 77% and for lymph node evaluation was approximately 75%. Esophageal EUS offers useful information to clinicians caring for patients with esophageal cancer, impacts clinical decision making, and should be used in

Computed tomography fluoroscopy-guided placement of iliosacral screws in patients with unstable posterior pelvic fractures

International Nuclear Information System (INIS)

Iguchi, Toshihiro; Ogawa, Ken-Ichi; Doi, Takeshi; Munetomo, Kazuo; Miyasho, Koji; Hiraki, Takao; Kanazawa, Susumu; Ozaki, Toshifumi

2010-01-01

The purpose of this study was to evaluate retrospectively the safety and effectiveness of the computed tomography (CT) fluoroscopy-guided placement of iliosacral screws in patients with unstable posterior pelvic fractures. Six patients (four women and two men; mean age 55.8 years; range 35-77 years) with unstable posterior pelvic fractures underwent iliosacral screw placement under CT fluoroscopy guidance between November 2007 and August 2008. Unstable pelvic ring injury (AO types B and C) was the indication for this procedure. In all the six patients except one, CT fluoroscopy-guided placement had been technically successful. In one patient, a second screw had been inserted, with a tilt to the caudal site, and slightly advanced into the extrasacral body; afterward, it could be exchanged safely for a shorter screw. Five patients and one patient underwent placement of two screws and one screw, respectively. The mean duration of the procedure was 15.0 min (range 9-30 min) per screw; the duration was 12.3 min and 18.2 min for the first and second screws, respectively. No complications requiring treatment occurred during or after the procedure. The mean clinical and radiologic follow-up period was 14 months (range 6-21 months). All pelvic injuries had healed satisfactorily, without complication, and all patients are now doing well clinically and can walk. CT fluoroscopy-guided placement of iliosacral screws is a safe and effective treatment in patients with unstable posterior pelvic fractures. (orig.)

EUS for the staging of gastric cancer: a meta-analysis.

Science.gov (United States)

Mocellin, Simone; Marchet, Alberto; Nitti, Donato

2011-06-01

The role of EUS in the locoregional staging of gastric carcinoma is undefined. We aimed to comprehensively review and quantitatively summarize the available evidence on the staging performance of EUS. We systematically searched the MEDLINE, Cochrane, CANCERLIT, and EMBASE databases for relevant studies published until July 2010. Formal meta-analysis of diagnostic accuracy parameters was performed by using a bivariate random-effects model. Fifty-four studies enrolling 5601 patients with gastric cancer undergoing disease staging with EUS were eligible for the meta-analysis. EUS staging accuracy across eligible studies was measured by computing overall sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR). EUS can differentiate T1-2 from T3-4 gastric cancer with high accuracy, with overall sensitivity, specificity, PLR, NLR, and DOR of 0.86 (95% CI, 0.81-0.90), 0.91 (95% CI, 0.89-0.93), 9.8 (95% CI, 7.5-12.8), 0.15 (95% CI, 0.11-0.21), and 65 (95% CI, 41-105), respectively. In contrast, the diagnostic performance of EUS for lymph node status is less reliable, with overall sensitivity, specificity, PLR, NLR, and DOR of 0.69 (95% CI, 0.63-0.74), 0.84 (95% CI, 0.81-0.88), 4.4 (95% CI, 3.6-5.4), 0.37 (95% CI, 0.32-0.44), and 12 (95% CI, 9-16), respectively. Results regarding single T categories (including T1 substages) and Bayesian nomograms to calculate posttest probabilities for any target condition prevalence are also provided. Statistical heterogeneity was generally high; unfortunately, subgroup analysis did not identify a consistent source of the heterogeneity. Our results support the use of EUS for the locoregional staging of gastric cancer, which can affect the therapeutic management of these patients. However, clinicians must be aware of the performance limits of this staging tool. Copyright © 2011 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

Accuracy Assessment of Immediate and Delayed Implant Placements Using CAD/CAM Surgical Guides.

Science.gov (United States)

Alzoubi, Fawaz; Massoomi, Nima; Nattestad, Anders

2016-10-01

The aim of this study is to assess the accuracy of immediately placed implants using Anatomage Invivo5 computer-assisted design/computer-assisted manufacturing (CAD/CAM) surgical guides and compare the accuracy to delayed implant placement protocol. Patients who had implants placed using Anatomage Invivo5 CAD/CAM surgical guides during the period of 2012-2015 were evaluated retrospectively. Patients who received immediate implant placements and/or delayed implant placements replacing 1-2 teeth were included in this study. Pre- and postsurgical images were superimposed to evaluate deviations at the crest, apex, and angle. A total of 40 implants placed in 29 patients were included in this study. The overall mean deviations measured at the crest, apex, and angle were 0.86 mm, 1.25 mm, and 3.79°, respectively. The means for the immediate group deviations were: crest = 0.85 mm, apex = 1.10, and angle = 3.49°. The means for the delayed group deviations were: crest = 0.88 mm, apex = 1.59, and angle = 4.29°. No statistically significant difference was found at the crest and angle; however, there was a statistically significant difference between the immediate and delayed group at the apex, with the immediate group presenting more accurate placements at the apical point than the delayed group. CAD/CAM surgical guides can be reliable tools to accurately place implants immediately and/or in a delayed fashion. No statistically significant differences were found between the delayed and the immediate group at the crest and angle, however apical position was more accurate in the immediate group.

Fluoroscopic-guided covered metallic stent placement for gastric outlet obstruction and post-operative gastroenterostomy anastomotic stricture

Energy Technology Data Exchange (ETDEWEB)

Lee, Jeong Min; Han, Young Min; Kim, Chong Soo; Lee, Sang Young; Lee, Soo Teik; Yang, Doo Hyun

2001-07-01

AIM: To evaluate the feasibility and safety of fluoroscopic-guided covered metallic stent placements in providing palliative care for patients with inoperable malignant gastric outlet obstruction. MATERIALS AND METHODS: Under fluoroscopic guidance, placement of self-expandable, covered stents was attempted in 20 patients with inoperable or recurrent gastric cancer (age range 36-79 years). All patients had inoperable gastric outlet obstruction, 13 with native anatomy and seven with post-operative anatomy (gastrointestinal anastomotic sites). All patients had intolerance to oral alimentation and/or vomiting after ingestion. Success was defined both technically and clinically. RESULTS: The placement of the stent was technically successful in 18 patients and failed in two patients (technical success: 90%). The cause of the technical failures was an inability to negotiate the guide wire through the obstruction sites in spite of the use of both fluoroscopic and endoscopic guidance. After stent placement, 15 patients were able to ingest at least liquids and had a markedly decreased incidence of vomiting (clinical success: 75%). During the mean follow-up of 6 weeks, there have been no stent reocclusion and no life-threatening complications except migration of two stents in one patient. CONCLUSION: Fluoroscopically guided covered metallic stent placement appears to be valuable for the palliative treatment of malignant obstruction of gastric outlet and post-operative gastrointestinal anastomoses. Lee, J.M. et al. (2001)

Magnet Fiducialization with Coordinate Measuring Machines

Energy Technology Data Exchange (ETDEWEB)

Friedsam, H.; Oren, W.; Pietryka, M.; /SLAC

2005-08-12

One of the fundamental alignment problems encountered when building a particle accelerator is the transfer of a component's magnetic centerline position to external fiducials. This operation, dubbed fiducialization, is critical because it can contribute significantly to the alignment error budget. The fiducialization process requires two measurements: (1) from magnetic centerline to mechanical centerline, and (2) from mechanical centerline to external fiducials. This paper will focus on methods for observing the second measurement. Two Stanford Linear Collider (SLC) examples are presented. The object of magnet fiducialization is to relate the magnet-defined beamline position to exterior reference surfaces. To be useful for later component alignment, this relationship must be established in a manner consistent with overall positioning tolerances. The error budget for the SLC's {+-} 100 {micro}m component to component alignment tolerance is as follows: magnetic centerline to mechanical centerline--{sigma} = {+-}30 {micro}m; mechanical centerline to fiducial marks--{sigma} = {+-}50 {micro}m; and fiducial marks to adjacent components--{sigma} = {+-}80 {micro}m; the TOTAL {sigma} = {+-}100 {micro}m. The offset between the mechanical and magnetic centerlines of well-known magnets is generally smaller than the {+-}30 {micro}m measurement tolerance. It is commonly assumed to be zero without measurement. When this tiny value must be measured, extreme care is necessary to avoid obscuring the offset with measurement tool registration errors. In contrast, the mechanical centerline to fiducial measurement must be performed on every magnet. The 50 {micro}m tolerance for this operation is only slightly larger and pushes conventional surveying technology to its limit.

Magnet Fiducialization with Coordinate Measuring Machines

International Nuclear Information System (INIS)

Friedsam, H.; Oren, W.; Pietryka, M.; SLAC

2005-01-01

One of the fundamental alignment problems encountered when building a particle accelerator is the transfer of a component's magnetic centerline position to external fiducials. This operation, dubbed fiducialization, is critical because it can contribute significantly to the alignment error budget. The fiducialization process requires two measurements: (1) from magnetic centerline to mechanical centerline, and (2) from mechanical centerline to external fiducials. This paper will focus on methods for observing the second measurement. Two Stanford Linear Collider (SLC) examples are presented. The object of magnet fiducialization is to relate the magnet-defined beamline position to exterior reference surfaces. To be useful for later component alignment, this relationship must be established in a manner consistent with overall positioning tolerances. The error budget for the SLC's ± 100 (micro)m component to component alignment tolerance is as follows: magnetic centerline to mechanical centerline--σ = ±30 (micro)m; mechanical centerline to fiducial marks--σ = ±50 (micro)m; and fiducial marks to adjacent components--σ = ±80 (micro)m; the TOTAL σ = ±100 (micro)m. The offset between the mechanical and magnetic centerlines of well-known magnets is generally smaller than the ±30 (micro)m measurement tolerance. It is commonly assumed to be zero without measurement. When this tiny value must be measured, extreme care is necessary to avoid obscuring the offset with measurement tool registration errors. In contrast, the mechanical centerline to fiducial measurement must be performed on every magnet. The 50 (micro)m tolerance for this operation is only slightly larger and pushes conventional surveying technology to its limit

Endoscopic Ultrasound-Guided Fine Needle Aspiration versus Percutaneous Ultrasound-Guided Fine Needle Aspiration in Diagnosis of Focal Pancreatic Masses.

Science.gov (United States)

Okasha, Hussein Hassan; Naga, Mazen Ibrahim; Esmat, Serag; Naguib, Mohamed; Hassanein, Mohamed; Hassani, Mohamed; El-Kassas, Mohamed; Mahdy, Reem Ezzat; El-Gemeie, Emad; Farag, Ali Hassan; Foda, Ayman Mohamed

2013-10-01

Pancreatic carcinoma is one of the leading cancer morbidity and mortality world-wide. Controversy has arisen about whether the percutaneous approach with computed tomography/ultrasonography-guidance fine needle aspiration (US-FNA) or endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is the preferred method to obtain diagnostic tissue. Our purpose of this study is to compare between the diagnostic accuracy of EUS-FNA and percutaneous US-FNA in diagnosis of pancreatic cancer. A total of 197 patients with pancreatic masses were included in the study, 125 patients underwent US-FNA (Group 1) and 72 patients underwent EUS-FNA (Group 2). EUS-FNA has nearly the same accuracy (88.9%) as US-FNA (87.2%) in diagnosis of pancreatic cancer. The sensitivity, specificity, positive predictive value and negative predictive value for EUS-FNA was 84%, 100%, 100%, 73.3% respectively. It was 85.5%, 90.4%, 94.7%, 76% respectively for US-FNA. EUS-FNA had a lower complication rate (1.38%) than US-FNA (5.6%). EUS-FNA has nearly the same accuracy as US-FNA of pancreatic masses with a lower complication rate.

Clinical Experience With Image-Guided Radiotherapy in an Accelerated Partial Breast Intensity-Modulated Radiotherapy Protocol

International Nuclear Information System (INIS)

Leonard, Charles E.; Tallhamer, Michael M.S.; Johnson, Tim; Hunter, Kari C.M.D.; Howell, Kathryn; Kercher, Jane; Widener, Jodi; Kaske, Terese; Paul, Devchand; Sedlacek, Scot; Carter, Dennis L.

2010-01-01

Purpose: To explore the feasibility of fiducial markers for the use of image-guided radiotherapy (IGRT) in an accelerated partial breast intensity modulated radiotherapy protocol. Methods and Materials: Nineteen patients consented to an institutional review board approved protocol of accelerated partial breast intensity-modulated radiotherapy with fiducial marker placement and treatment with IGRT. Patients (1 patient with bilateral breast cancer; 20 total breasts) underwent ultrasound guided implantation of three 1.2- x 3-mm gold markers placed around the surgical cavity. For each patient, table shifts (inferior/superior, right/left lateral, and anterior/posterior) and minimum, maximum, mean error with standard deviation were recorded for each of the 10 BID treatments. The dose contribution of daily orthogonal films was also examined. Results: All IGRT patients underwent successful marker placement. In all, 200 IGRT treatment sessions were performed. The average vector displacement was 4 mm (range, 2-7 mm). The average superior/inferior shift was 2 mm (range, 0-5 mm), the average lateral shift was 2 mm (range, 1-4 mm), and the average anterior/posterior shift was 3 mm (range, 1 5 mm). Conclusions: This study shows that the use of IGRT can be successfully used in an accelerated partial breast intensity-modulated radiotherapy protocol. The authors believe that this technique has increased daily treatment accuracy and permitted reduction in the margin added to the clinical target volume to form the planning target volume.

The endoscopic ultrasonography-guided rendezvous technique for biliary cannulation: a technical review.

Science.gov (United States)

Isayama, Hiroyuki; Nakai, Yousuke; Kawakubo, Kazumichi; Kawakami, Hiroshi; Itoi, Takao; Yamamoto, Natsuyo; Kogure, Hirofumi; Koike, Kazuhiko

2013-04-01

Steady progress is being made in endoscopic biliary intervention, especially endoscopic ultrasonography (EUS)-guided procedures. The EUS-guided rendezvous technique (EUS-RV) is a salvage method for failed selective biliary cannulation. The overall success rate of EUS-RV in 247 cases from seven published articles was 74 % and the incidence of complications was 11 %. The main cause of failed rendezvous cannulation was difficulty passing a biliary stricture or papilla due to poor guidewire (GW) manipulation. A recent large study found a 98.3 % success rate and superiority to precutting. This report suggested using a hydrophilic guidewire. Major complications were bleeding (0.8 %), bile leakage (1.2 %), peritonitis (0.4 %), pneumoperitoneum (0.2 %), and pancreatitis (1.6 %). The approach routes for EUS-RV were transgastric, transduodenal short position, and transduodenal long position. The appropriate route for each patient should be used. GW selection for EUS-RV is critical, and a hydrophilic GW might be the most useful. The catheter can be inserted through the papilla alongside or over the wire. Alongside cannulation is convenient, but difficult. The problem with the over-the-wire technique is withdrawal of the GW in the accessory channel. EUS-RV is effective and safe, but is not established. The efficacy should be confirmed in a prospective comparative trial, and the necessary specialist equipment should be developed.

Endoscopic ultrasound-guided coil or glue injection in post-cyanoacrylate gastric variceal re-bleed.

Science.gov (United States)

Mukkada, Roy J; Antony, Rajesh; Chooracken, Mathew J; Francis, Jose V; Chettupuzha, Antony P; Mathew, Pradeep G; Augustine, Philip; Koshy, Abraham

2018-04-09

N-butyl-cyanoacrylate injection is recommended in bleeding/recently bled gastric varices. However, cyanoacrylate injection is associated with re-bleed in 25% to 50% of patients. Endoscopic ultrasound (EUS)-guided coil application is an emerging treatment modality for bleeding gastric varices. The aim of this study was to compare EUS-guided coil application combined with or without cyanoacrylate glue injection to injection alone in post-glue gastric variceal re-bleed. A retrospective analysis of a prospectively maintained database was performed. Thirty patients who re-bled after cyanoacrylate injection and who had EUS-guided coil application to gastric varices were included. The comparison was done with data of 51 patients who had only repeat cyanoacrylate injection. Both groups had a follow up for 12 months. EUS-guided coil application was done under endosonographic guidance. A single coil was placed in 7, two coils in each of 13 patients, three in 5, four in 3, five in one, and 6 coils in one patient. In addition, cyanoacrylate glue injection was given in 15 patients. Eight patients had repeat EUS-guided coil application 1 month later. Re-bleed and mortality were assessed. Coilng: Six out of 30 (20%) patients re-bled during follow up of 9 to 365 days. Three out of 30 (10%) died. One patient died 9 days after the procedure due to acute respiratory distress syndrome, one died 4 months after the procedure due to a re-bleed and one 5 months after the procedure due to spontaneous bacterial peritonitis. Glue only: 26/51 (51%) re-bled during follow up of 45 to 365 days. EUS-guided coil application resulted in significantly less re-bleed than glue-only (Kaplan-Meir survival analysis with log-rank test, z = 5.4, p guided coil application with/without cyanoacrylate injection for the obliteration of gastric varices is effective for post-cyanoacrylate gastric variceal re-bleed.

Image guided placement of temporary anchorage devices for tooth movement

Energy Technology Data Exchange (ETDEWEB)

Bahl-Palomo, L.; Bissada, N. [Case Western Reserve Univ. School of Dental Medicine, Dept. of Periodontics, Cleveland, OH (United States); Palomo, J.M.; Hans, M.G. [Case Western Reserve Univ. School of Dental Medicine, Dept. of Orthodontics, Cleveland, OH (United States)

2007-06-15

The aim of this project is to develop an image guided protocol for placement of a temporary anchorage device without surgically reflecting a mucoperiosteal flap. Eighteen orthodontic cases were selected for skeletal anchorage from the department of orthodontics at Case University. CBCT images of the subjects were taken using the Hitachi CB MercuRay system set at 15 mA, 120 kVp. CBCT images evaluated the ideal location for TAD placement in three dimensions. Horizontal and vertical linear measurements were taken from fixed dental landmarks to clearly define the location for placement. Transverse slices were used to evaluate the thickness of the buccal plate. Using the transverse view, the angle of insertion was determined such that the maximum buccal plate surface area would contact the screw. TADs were placed in the optimum location, with the most appropriate angle of insertion using a closed approach and with minimal local anesthesia and without flap elevation. Results: All TADs were placed without anatomic encroachment and enabled fixed orthodontic anchorage. (orig.)

Image guided placement of temporary anchorage devices for tooth movement

International Nuclear Information System (INIS)

Bahl-Palomo, L.; Bissada, N.; Palomo, J.M.; Hans, M.G.

2007-01-01

The aim of this project is to develop an image guided protocol for placement of a temporary anchorage device without surgically reflecting a mucoperiosteal flap. Eighteen orthodontic cases were selected for skeletal anchorage from the department of orthodontics at Case University. CBCT images of the subjects were taken using the Hitachi CB MercuRay system set at 15 mA, 120 kVp. CBCT images evaluated the ideal location for TAD placement in three dimensions. Horizontal and vertical linear measurements were taken from fixed dental landmarks to clearly define the location for placement. Transverse slices were used to evaluate the thickness of the buccal plate. Using the transverse view, the angle of insertion was determined such that the maximum buccal plate surface area would contact the screw. TADs were placed in the optimum location, with the most appropriate angle of insertion using a closed approach and with minimal local anesthesia and without flap elevation. Results: All TADs were placed without anatomic encroachment and enabled fixed orthodontic anchorage. (orig.)

Observation of unusual critical region behavior in the magnetic susceptibility of EuSe

Science.gov (United States)

Bykovetz, N.; Klein, J.; Lin, C. L.

2018-05-01

The Europium Chalcogenides (EuCh: EuO, EuS, EuSe, and EuTe) have been regarded as model examples of simple, cubic, Heisenberg exchange coupled magnetic systems, with a ferromagnetic nearest-neighbor exchange constant J1 and an antiferromagnetic next-nearest-neighbor constant J2. Unlike the other EuCh, EuSe exhibits a range of complex magnetic behaviors, the latter being attributed to EuSe being near the point where J2=-J1, where its magnetism appears to consist of nearly de-coupled 2D ferromagnetic sheets. Analysis of precision SQUID measurements of the magnetic susceptibility χ in EuSe showed that in the region from ˜Tc to ˜2Tc, a fit of the data to the critical equation χ = χ2Tc(T/Tc-1)-γ gives γ=2.0, an exponent not predicted by any current theory. Additionally, this fit predicts that Tc should be ˜0K. We tentatively interpret this by saying that in the paramagnetic region the system "thinks" EuSe should not order above T=0. Tc=0K is predicted by the Mermin-Wagner theorem (MW) for Heisenberg-coupled 2D magnetic systems, and we can show that when J2=-J1, MW can also be applied to the J1, J2 exchange model of the EuCh to give a rigorous Tc=0 prediction. Under 10 kbar applied pressure EuSe exhibits a different γ and fitted Tc. An additional, and rather strange, critical-region effect was discovered. The EuSe sample was found to exhibit a relaxation effect in a small range of temperatures, just above and just below the actual Tc of 4.7K, with time constants of up to 5 minutes. We cannot yet fully explain this observed macroscopic effect.

Endosonography guided management of pancreatic fluid collections

DEFF Research Database (Denmark)

Vilmann, Andreas S; Menachery, John; Tang, Shou-Jiang

2015-01-01

complications of pancreatitis can include acute peri-pancreatic fluid collection, acute necrotic collection, pseudocyst formation, and walled-off necrosis. Interventional endoscopic ultrasound (EUS) has been increasing utilized in managing these local complications. After performing a PubMed search, the authors...... manually applied pre-defined inclusion criteria or a filter to identify publications relevant to EUS and pancreatic collections (PFCs). The authors then reviewed the utility, efficacy, and risks associated with using therapeutic EUS and involved EUS devices in treating PFCs. Due to the development...... to diagnose PFCs and perform image-guided interventions. After draining a PFC, the amount of tissue necrosis is the most important predictor of a successful outcome. Hence, it seems logical to classify these collections based on their percentage of necrotic component or debris present when viewed by imaging...

Accuracy and Quality Assessment of EUS-FNA: A Single-Center Large Cohort of Biopsies

Directory of Open Access Journals (Sweden)

Benjamin Ephraim Bluen

2012-01-01

Full Text Available Introduction. Thorough quality control (QC study with systemic monitoring and evaluation is crucial to optimizing the effectiveness of EUS-FNA. Methods. Retrospective analysis was composed of investigating consecutive patient files that underwent EUS-FNA. QC specifically focused on diagnostic accuracy, impacts on preexisting diagnoses, and case management. Results. 268 patient files were evaluated. EUS-FNA cytology helped establish accurate diagnoses in 92.54% (248/268 of patients. Sensitivity, specificity, PPV, NPV, and accuracy were 83%, 100%, 100%, 91.6%, and 94%, respectively. The most common biopsy site was the pancreas (68%. The most accurate location for EUS-FNA was the esophagus, 13/13 (100%, followed by the pancreas (89.6%. EUS-FNA was least informative for abdominal lymph nodes (70.5%. After FNA and followup, eight false negatives for tumors were found (3%, while 7.5% of samples still lacked a definitive diagnosis. Discussion. QC suggests that the diagnostic accuracy of EUS-FNA might be improved further by (1 taking more FNA passes from suspected lesions, (2 optimizing needle selection (3 having an experienced echo-endoscopist available during the learning curve, and (4 having a cytologist present during the procedure. QC also identified remediable reporting errors. In conclusion, QC study is valuable in identifying weaknesses and thereby augmenting the effectiveness of EUS-FNA.

Palliation of malignant gastric obstruction : fluoroscopic guided covered metallic stent placement

International Nuclear Information System (INIS)

Lee, Jeong Min; Han, Young Min; Kim, Chong Soo; Lee, Sang Yong; Choi, Ki Chul; Lee, Soo Tak; Han, Hyun Young

2000-01-01

To demonstrate the feasibility and clinical efficacy of self-expanding, covered metallic stent placement for the palliative treatment of malignant gastric obstruction. Under fluoroscopic guidance, the placement of self-expanding, covered stents was attempted in 23 patients (age range, 31-78 years) with inoperable or recurrent gastric malignancies. All 23 suffered dysphagia and/or vomiting after the ingestion of soft foods, or swallowing difficulty. Three different types of self-expanding, covered metallic stents were used and in all patients, these were placed perorally using over the guide wire technique. Success was defined both technically and clinically. Stent placement was technically successful in 19 patients (82.6%) but because the guidewire failed to successfully negotiate the sites at which there was obstruction, was unsuccessful in four (17.4%). Stent placement was well tolerated in all patients except one, in whom an acutely angled efferent loop from remnant stomach was present. In this case, stent placement required a strong metallic guidewire. After placement, 17 of the 19 patients (89.5%) were able to ingest solid and/or soft foods without dysphagia and showed a markedly decreased incidence of vomiting. Two others showed some improvement in the frequency of vomiting but were able to ingest only a liquid diet. In one patient, the stent migrated two days after the procedure. During the follow-up period of 2-7 months (mean, 74 days), there were no clinically significant complications. For the short-term palliative treatment of patients with gastric inlet or outlet obstruction, the placement of self-expanding metallic stents has proven relatively easy and safe, as well as reasonably effective. (author)

Six-dimensional correction of intra-fractional prostate motion with CyberKnife stereotactic body radiation therapy

Directory of Open Access Journals (Sweden)

Sean eCollins

2011-12-01

Full Text Available AbstractLarge fraction radiation therapy offers a shorter course of treatment and radiobiological advantages for prostate cancer treatment. The CyberKnife is an attractive technology for delivering large fraction doses based on the ability to deliver highly conformal radiation therapy to moving targets. In addition to intra-fractional translational motion (left-right, superior-inferior and anterior-posterior, prostate rotation (pitch, roll and yaw can increase geographical miss risk. We describe our experience with six-dimensional (6D intrafraction prostate motion correction using CyberKnife stereotactic body radiation therapy (SBRT. Eighty-eight patients were treated by SBRT alone or with supplemental external radiation therapy. Trans-perineal placement of four gold fiducials within the prostate accommodated X-ray guided prostate localization and beam adjustment. Fiducial separation and non-overlapping positioning permitted the orthogonal imaging required for 6D tracking. Fiducial placement accuracy was assessed using the CyberKnife fiducial extraction algorithm. Acute toxicities were assessed using Common Toxicity Criteria (CTC v3. There were no Grade 3, or higher, complications and acute morbidity was minimal. Ninety-eight percent of patients completed treatment employing 6D prostate motion tracking with intrafractional beam correction. Suboptimal fiducial placement limited treatment to 3D tracking in 2 patients. Our experience may guide others in performing 6D correction of prostate motion with CyberKnife SBRT.

Reliability of implant placement with stereolithographic surgical guides generated from computed tomography: clinical data from 94 implants.

Science.gov (United States)

Ersoy, Ahmet Ersan; Turkyilmaz, Ilser; Ozan, Oguz; McGlumphy, Edwin A

2008-08-01

Dental implant placement requires precise planning with regard to anatomic limitations and restorative goals. The aim of this study was to evaluate the match between the positions and axes of the planned and placed implants using stereolithographic (SLA) surgical guides. Ninety-four implants were placed using SLA surgical guides generated from computed tomography (CT) between 2005 and 2006. Radiographic templates were used for all subjects during CT imaging. After obtaining three-dimensional CT images, each implant was virtually placed on the CT images. SLA surgical guides, fabricated using an SLA machine with a laser beam to polymerize the liquid photo-polymerized resin, were used during implant placement. A new CT scan was taken for each subject following implant placement. Special software was used to fuse the images of the planned and placed implants, and the locations and axes were compared. Compared to the planned implants, the placed implants showed angular deviation of 4.9 degrees+/-2.36 degrees, whereas the mean linear deviation was 1.22+/-0.85 mm at the implant neck and 1.51+/-1 mm at the implant apex. Compared to the implant planning, the angular deviation and linear deviation at the neck and apex of the placed maxillary implants were 5.31 degrees+/-0.36 degrees, 1.04+/-0.56 mm, and 1.57+/-0.97 mm, respectively, whereas corresponding figures for placed mandibular implants were 4.44 degrees+/-0.31 degrees, 1.42+/-1.05 mm, and 1.44+/-1.03 mm, respectively. SLA surgical guides using CT data may be reliable in implant placement and make flapless implant placement possible.

Cardiac embolization of an implanted fiducial marker for hepatic stereotactic body radiotherapy: a case report

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Hennessey Hooman

2009-11-01

Full Text Available Abstract Introduction In liver stereotactic body radiotherapy, reduction of normal tissue irradiation requires daily image guidance. This is typically accomplished by imaging a surrogate to the tumor. The surrogate is often an implanted metal fiducial marker. There are few reports addressing the specific risks of hepatic fiducial marker implantation. These risks are assumed to be similar to percutaneous liver biopsies which are associated with a 1-4% complication rate - almost always pain or bleeding. To the best of our knowledge, we present the first case of such a fiducial marker migrating to the heart. Case presentation An 81-year-old Caucasian man (5 years post-gastrectomy for a gastric adenocarcinoma was referred post-second line palliative chemotherapy for radiotherapy of an isolated liver metastasis. It was decided to proceed with treatment and platinum fiducials were chosen for radiation targeting. Under local anesthesia, three Nester embolization coils (Cook Medical Inc., Bloomington, IN, USA were implanted under computed tomography guidance. Before the placement of each coil, the location of the tip of the delivery needle was confirmed by computed tomography imaging. During the procedure, the third coil unexpectedly migrated through the hepatic vein to the inferior vena cava and lodged at the junction of the vena cava and the right atrium. The patient remained asymptomatic. He was immediately referred to angiography for extraction of the coil. Using fluoroscopic guidance, an EN Snare Retrieval System (Hatch Medical L.L.C., Snellville, GA, USA was introduced through a jugular catheter; it successfully grasped the coil and the coil was removed. The patient was kept overnight for observation and no immediate or delayed complications were encountered due to the migration or retrieval of the coil. He subsequently went on to be treated using the remaining fiducials. Conclusion Implanted fiducial markers are increasingly used for stereotactic

Dosimetric implications of residual seminal vesicle motion in fiducial-guided intensity-modulated radiotherapy for prostate cancer

International Nuclear Information System (INIS)

Stenmark, Matthew H.; Vineberg, Karen; Ten Haken, Randall K.; Hamstra, Daniel A.; Feng, Mary

2012-01-01

To determine whether residual interfraction seminal vesicle (SV) displacement necessitates specific planning target volume (PTV) margins during fiducial-guided intensity modulated radiation therapy (IMRT) of the prostate. A planning computed tomography (CT) scan and 2 subsequent CT scans were prospectively obtained for 20 prostate cancer patients with intraprostatic fiducial markers. After CT registration, SV displacement relative to the prostate was quantified as a function of margin size for both the proximal (1 cm) SV (PSV) and the full SV (FSV). Two IMRT plans were simulated for each patient (prostate + PSV and prostate + FSV) both with a uniform 5-mm PTV margin. Minimum clinical target volume (CTV) dose (D min ) and the volume of SV receiving 95% of the prescription dose (V 95% ) were assessed during treatment and compared with the initial plan. In all cases, SV displacement with respect to the prostate was greater for the FSV compared with the PSV. To ensure at least 95% geometrical coverage of the CTV for 90% of patients, margins of 5 and 8 mm were required for the PSV and FSV, respectively. Dosimetrically, residual SV displacement had minimal impact on PSV coverage compared with FSV coverage. For the PSV D min was ≥95% of the prescribed dose in 90% of patients with an overall mean V 95% of 99.6 ± 0.8%; for the FSV D min was ≥95% of the prescribed dose in only 45% of patients with a mean V 95% of 97.9 ± 2.4%. The SVs move differentially from the prostate and exhibit greater variation with increasing distance from the prostate. For plans targeting just the prostate and PSVs, 5-mm PTV expansions are adequate. However, despite daily localization of the prostate, larger PTV margins are required for cases where the intent is to completely cover the FSV.

Bone Reduction to Facilitate Immediate Implant Placement and Loading Using CAD/CAM Surgical Guides for Patients With Terminal Dentition.

Science.gov (United States)

Alzoubi, Fawaz; Massoomi, Nima; Nattestad, Anders

2016-10-01

The aim of this study is to present a method, using 3 computer-aided design/computer-aided manufacturing (CAD/CAM) surgical guides, to accurately obtain the desired bone reduction followed by immediate implant placements and loading for patients diagnosed with terminal dentition. Patients who had bone reduction, implants placed, and immediate loading using Anatomage Invivo 5 CAD/CAM surgical guides between the period 2013 and 2015 were evaluated retrospectively. Patients diagnosed with terminal dentition and treated using the "3-guide technique" were identified. Pre- and postsurgical images were superimposed to evaluate deviations of the bone reduction and deviations at the crest, apex, and angle of implants placed. Twenty-six implants placed in 5 patients were included in this study. The overall deviation means measured for bone reduction was 1.98 mm. The overall deviation means measured for implant placement at the crest, apex, and angle were 1.43 mm, 1.90 mm, and 4.14°, respectively. The CAD/CAM surgical guide fabrication is an emerging tool that may facilitate the surgical process and aid in safe and predictable execution of bone reduction and immediate implant placement. Using 3 CAD/CAM surgical guides, a method is presented to obtain the desired bone reduction followed by immediate implant placement and loading for patients diagnosed with terminal dentition. This method may improve guide stability for patients with terminal dentition undergoing complete implant-supported treatment by taking advantage of the teeth to be extracted.

Prospective implementation of an algorithm for bedside intravascular ultrasound-guided filter placement in critically ill patients.

Science.gov (United States)

Killingsworth, Christopher D; Taylor, Steven M; Patterson, Mark A; Weinberg, Jordan A; McGwin, Gerald; Melton, Sherry M; Reiff, Donald A; Kerby, Jeffrey D; Rue, Loring W; Jordan, William D; Passman, Marc A

2010-05-01

Although contrast venography is the standard imaging method for inferior vena cava (IVC) filter insertion, intravascular ultrasound (IVUS) imaging is a safe and effective option that allows for bedside filter placement and is especially advantageous for immobilized critically ill patients by limiting resource use, risk of transportation, and cost. This study reviewed the effectiveness of a prospectively implemented algorithm for IVUS-guided IVC filter placement in this high-risk population. Current evidence-based guidelines were used to create a clinical decision algorithm for IVUS-guided IVC filter placement in critically ill patients. After a defined lead-in phase to allow dissemination of techniques, the algorithm was prospectively implemented on January 1, 2008. Data were collected for 1 year using accepted reporting standards and a quality assurance review performed based on intent-to-treat at 6, 12, and 18 months. As defined in the prospectively implemented algorithm, 109 patients met criteria for IVUS-directed bedside IVC filter placement. Technical feasibility was 98.1%. Only 2 patients had inadequate IVUS visualization for bedside filter placement and required subsequent placement in the endovascular suite. Technical success, defined as proper deployment in an infrarenal position, was achieved in 104 of the remaining 107 patients (97.2%). The filter was permanent in 21 (19.6%) and retrievable in 86 (80.3%). The single-puncture technique was used in 101 (94.4%), with additional dual access required in 6 (5.6%). Periprocedural complications were rare but included malpositioning requiring retrieval and repositioning in three patients, filter tilt >/=15 degrees in two, and arteriovenous fistula in one. The 30-day mortality rate for the bedside group was 5.5%, with no filter-related deaths. Successful placement of IVC filters using IVUS-guided imaging at the bedside in critically ill patients can be established through an evidence-based prospectively

Normal anatomy of the anal wall and perianal spaces: An EUS, MRI and cadaveric correlative study

International Nuclear Information System (INIS)

Chung, Soo Young; Ryu, Sie Tae; Park, Ki Soon; Lee, Yul; Bae, Sang Hoon; Kang, Heung Sik

1994-01-01

To understand the normal endosonographic anatomy of the perianal spaces, and to evaluate the diagnostic efficacy and limitation of endorectal sonography(EUS), correlative study with MRI, cadaveric sectional image and cadaveric MRI were performed. EUS images of the normal 6 perianal spaces (pelvirectal, ischiorectal, intersphincteric, subcutaneous, central, submucous space) which were bounded by internal and external anal sphincters, rectal wall and levator ani muscle were correlated with MRI in 10 normal persons, cadaveric sectional images and cadaveric MRI in 2 cadavers. Pelvirectal space located superior to levator ani muscle could be demonstrable only on anterior wall scan but could not be visualized on lateral or posterior wall scan on EUS. Five perianal spaces located inferior to levator ani muscle were well seen on anterior, lateral, and posterior wall EUS. MRI was superior to EUS in the evaluation of pelvirectal and ischiorectal spaces but equal or inferior to EUS in the evaluation of intersphincteric, subcutaneous, central and submucous spaces. EUS was valuable in the evaluation of perianal spaces inferior to levator ani muscle but was limited in the evaluation of perianal spaces superior to levator ani muscle

Bedside intravascular ultrasound-guided inferior vena cava filter placement in medical-surgical intensive care critically-ill patients

Directory of Open Access Journals (Sweden)

Mohammad A. Abusedera

2015-09-01

Conclusions: Bedside IVUS-guided filter placement in medical-surgical critically ill patient in intensive care unit is a feasible, safe and reliable technique for IVC interruption. IVUS may be the most appropriate tool to guide filter insertion in obese patient.

TEACHERS' GUIDES. WORLD HISTORY FOR THE ACADEMICALLY TALENTED. ADVANCED PLACEMENT EUROPEAN HISTORY.

Science.gov (United States)

AUGSPURGER, EVERETT F.; AND OTHERS

PREPARED BY TEACHERS AND SUPERVISORS WORKING WITH A 2-YEAR DEMONSTRATION PROJECT, THIS DOCUMENT CONTAINS GUIDES FOR A WORLD HISTORY COURSE (PREHISTORY TO EARLY 20TH CENTURY) FOR THE GIFTED AND AN ADVANCED PLACEMENT COURSE IN EUROPEAN HISTORY (ANCIENT CIVILIZATION TO EARLY 20TH CENTURY). STUDENTS ARE EXPECTED TO STUDY HISTORICAL ISSUES AND DEVELOP…

SU-E-J-219: Quantitative Evaluation of Motion Effects On Accuracy of Image-Guided Radiotherapy with Fiducial Markers Using CT Imaging

Energy Technology Data Exchange (ETDEWEB)

Ali, I; Oyewale, S; Ahmad, S; Algan, O [University of Oklahoma Health Sciences, Oklahoma City, OK (United States); Alsbou, N [Department of Electrical and Computer Engineering, Ada, OH (United States)

2014-06-01

Purpose: To investigate quantitatively patient motion effects on the localization accuracy of image-guided radiation with fiducial markers using axial CT (ACT), helical CT (HCT) and cone-beam CT (CBCT) using modeling and experimental phantom studies. Methods: Markers with different lengths (2.5 mm, 5 mm, 10 mm, and 20 mm) were inserted in a mobile thorax phantom which was imaged using ACT, HCT and CBCT. The phantom moved with sinusoidal motion with amplitudes ranging 0–20 mm and a frequency of 15 cycles-per-minute. Three parameters that include: apparent marker lengths, center position and distance between the centers of the markers were measured in the different CT images of the mobile phantom. A motion mathematical model was derived to predict the variations in the previous three parameters and their dependence on the motion in the different imaging modalities. Results: In CBCT, the measured marker lengths increased linearly with increase in motion amplitude. For example, the apparent length of the 10 mm marker was about 20 mm when phantom moved with amplitude of 5 mm. Although the markers have elongated, the center position and the distance between markers remained at the same position for different motion amplitudes in CBCT. These parameters were not affected by motion frequency and phase in CBCT. In HCT and ACT, the measured marker length, center and distance between markers varied irregularly with motion parameters. The apparent lengths of the markers varied with inverse of the phantom velocity which depends on motion frequency and phase. Similarly the center position and distance between markers varied inversely with phantom speed. Conclusion: Motion may lead to variations in maker length, center position and distance between markers using CT imaging. These effects should be considered in patient setup using image-guided radiation therapy based on fiducial markers matching using 2D-radiographs or volumetric CT imaging.

SU-E-J-219: Quantitative Evaluation of Motion Effects On Accuracy of Image-Guided Radiotherapy with Fiducial Markers Using CT Imaging

International Nuclear Information System (INIS)

Ali, I; Oyewale, S; Ahmad, S; Algan, O; Alsbou, N

2014-01-01

Purpose: To investigate quantitatively patient motion effects on the localization accuracy of image-guided radiation with fiducial markers using axial CT (ACT), helical CT (HCT) and cone-beam CT (CBCT) using modeling and experimental phantom studies. Methods: Markers with different lengths (2.5 mm, 5 mm, 10 mm, and 20 mm) were inserted in a mobile thorax phantom which was imaged using ACT, HCT and CBCT. The phantom moved with sinusoidal motion with amplitudes ranging 0–20 mm and a frequency of 15 cycles-per-minute. Three parameters that include: apparent marker lengths, center position and distance between the centers of the markers were measured in the different CT images of the mobile phantom. A motion mathematical model was derived to predict the variations in the previous three parameters and their dependence on the motion in the different imaging modalities. Results: In CBCT, the measured marker lengths increased linearly with increase in motion amplitude. For example, the apparent length of the 10 mm marker was about 20 mm when phantom moved with amplitude of 5 mm. Although the markers have elongated, the center position and the distance between markers remained at the same position for different motion amplitudes in CBCT. These parameters were not affected by motion frequency and phase in CBCT. In HCT and ACT, the measured marker length, center and distance between markers varied irregularly with motion parameters. The apparent lengths of the markers varied with inverse of the phantom velocity which depends on motion frequency and phase. Similarly the center position and distance between markers varied inversely with phantom speed. Conclusion: Motion may lead to variations in maker length, center position and distance between markers using CT imaging. These effects should be considered in patient setup using image-guided radiation therapy based on fiducial markers matching using 2D-radiographs or volumetric CT imaging

Extra Luminal Entrapment of Guide Wire; A Rare Complication of Central Venous Catheter Placement in Right Internal Jugular Vein.

Science.gov (United States)

Ansari, Md Abu Masud; Kumar, Naveen; Kumar, Shailesh; Kumari, Sarita

2016-10-01

Central venous Catheterization (CVC) is a commonly performed procedure for venous access. It is associated with several complications. We report a rare case of extra luminal entrapment of guide wire during CVC placement in right jugular vein. We report a case of 28 years old female patient presented in our emergency with history of entrapped guide wire in right side of neck during CVC. X-ray showed coiling of guide wire in neck. CT Angiography showed guide wire coursing in between common carotid artery and internal jugular vein (IJV), closely abutting the wall of both vessels. The guide wire was coiled with end coursing behind the esophageal wall. Guide wire was removed under fluoroscopic guide manipulation under local anesthesia. We want to emphasize that even though CVC placement is common and simple procedure, serious complication can occur in hands of untrained operator. The procedure should be performed under supervision, if done by trainee. Force should never be applied to advance the guide wire if resistance is encountered.

Accurate pre-surgical determination for self-drilling miniscrew implant placement using surgical guides and cone-beam computed tomography.

Science.gov (United States)

Miyazawa, Ken; Kawaguchi, Misuzu; Tabuchi, Masako; Goto, Shigemi

2010-12-01

Miniscrew implants have proven to be effective in providing absolute orthodontic anchorage. However, as self-drilling miniscrew implants have become more popular, a problem has emerged, i.e. root contact, which can lead to perforation and other root injuries. To avoid possible root damage, a surgical guide was fabricated and cone-beam computed tomography (CBCT) was used to incorporate guide tubes drilled in accordance with the planned direction of the implants. Eighteen patients (5 males and 13 females; mean age 23.8 years; minimum 10.7, maximum 45.5) were included in the study. Forty-four self-drilling miniscrew implants (diameter 1.6, and length 8 mm) were placed in interradicular bone using a surgical guide procedure, the majority in the maxillary molar area. To determine the success rates, statistical analysis was undertaken using Fisher's exact probability test. CBCT images of post-surgical self-drilling miniscrew implant placement showed no root contact (0/44). However, based on CBCT evaluation, it was necessary to change the location or angle of 52.3 per cent (23/44) of the guide tubes prior to surgery in order to obtain optimal placement. If orthodontic force could be applied to the screw until completion of orthodontic treatment, screw anchorage was recorded as successful. The total success rate of all miniscrews was 90.9 per cent (40/44). Orthodontic self-drilling miniscrew implants must be inserted carefully, particularly in the case of blind placement, since even guide tubes made on casts frequently require repositioning to avoid the roots of the teeth. The use of surgical guides, fabricated using CBCT images, appears to be a promising technique for placement of orthodontic self-drilling miniscrew implants adjacent to the dental roots and maxillary sinuses.

Endoscopic ultrasound in pancreatic cancer: innovative applications beyond the basics.

Science.gov (United States)

Yoo, Joseph; Kistler, C Andrew; Yan, Linda; Dargan, Andrew; Siddiqui, Ali A

2016-12-01

Endoscopic ultrasound (EUS) has become a mainstay in assisting in the diagnosis and staging of pancreatic cancer. In addition, EUS provides a modality to treat chronic pain through celiac plexus neurolysis. Currently, there is growing data and utilization of EUS in more diverse and innovative applications aimed at providing more sophisticated diagnostic, prognostic and therapeutic options for patients with pancreatic cancer. EUS delivery of chemotherapy, viral and biological vectors and fiducial markers may eventually revolutionize the way clinicians approach the care of a patient with pancreatic cancer.

Planning and implementing an implanted fiducial programme for prostate cancer radiation therapy

International Nuclear Information System (INIS)

Thompson, A.; Owen, R.; Laferlita, M.; Fox, C.; Foroudi, F.; Tai, K. H.; Styles, C.

2008-01-01

Full text: Using implanted gold seeds as fiducial markers to verify the position of the prostate in radiation therapy is well accepted and is becoming the standard of practice and requirement for international multicentre trials. In 2006 the decision was made at the Peter MacCallum Caner Centre (Peter Mac) to plan for and implement this process as standard clinical practice for radical dose prostate treatments (74-78 Gy). Before this, programme verification of field placement for prostate cancer radiation treatment was routinely carried out using regular off-line electronic portal imaging with matching of bony anatomy. A small multidisciplinary team investigated and assisted in the implementation of this new practice across the Peter Mac sites at East Melbourne and our three satellite centres. Issues considered included seed size, number and position in the prostate, implant equipment, imaging equipment and procedure and consent and information forms. The use of a custom made fiducial pack, comprehensive patient information and a daily on-line imaging process was implemented. The experience of the first 28 patients at Peter Mac from January 2007 to May 2007 inclusive is reported on.

[Endoscopic ultrasound guided rendezvous for biliary drainage].

Science.gov (United States)

Knudsen, Marie Høxbro; Vilmann, Peter; Hassan, Hazem; Karstensen, John Gésdal

2015-04-27

Endoscopic retrograde cholangiography (ERCP) is currently standard treatment for biliary drainage. Endoscopic ultrasound guided rendezvous (EUS-RV) is a novel method to overcome an unsuccessful biliary drainage procedure. Under endoscopic ultrasound guidance a guidewire is passed via a needle from the stomach or duodenum to the common bile duct and from there on to the duodenum enabling ERCP. With a relatively high rate of success EUS-RV should be considered as an alternative to biliary drainage and surgical intervention.

MRI-guided robotic system for transperineal prostate interventions: proof of principle

International Nuclear Information System (INIS)

Van den Bosch, Michiel R; Moman, Maaike R; Van Vulpen, Marco; Battermann, Jan J; Lagendijk, Jan J W; Moerland, Marinus A; Duiveman, Ed; Van Schelven, Leonard J; De Leeuw, Hendrik

2010-01-01

In this study, we demonstrate the proof of principle of the University Medical Center Utrecht (UMCU) robot dedicated to magnetic resonance imaging (MRI)-guided interventions in patients. The UMCU robot consists of polymers and non-ferromagnetic materials. For transperineal prostate interventions, it can be placed between the patient's legs inside a closed bore 1.5T MR scanner. The robot can manually be translated and rotated resulting in five degrees of freedom. It contains a pneumatically driven tapping device to automatically insert a needle stepwise into the prostate using a controller unit outside the scanning room. To define the target positions and to verify the needle insertion point and the needle trajectory, a high-resolution 3D balanced steady state free precession (bSSFP) scan that provides a T2/T1-weighted contrast is acquired. During the needle insertion fast 2D bSSFP images are generated to track the needle on-line. When the target position is reached, the radiation oncologist manually places a fiducial gold marker (small seed) at this location. In total two needle trajectories are used to place all markers. Afterwards, a high-resolution 3D bSSFP scan is acquired to visualize the fiducial gold markers. Four fiducial gold markers were placed transperineally into the prostate of a patient with a clinical stage T3 prostate cancer. In the generated scans, it was possible to discriminate the patient's anatomy, the needle and the markers. All markers were delivered inside the prostate. The procedure time was 1.5 h. This study proves that MRI-guided needle placement and seed delivery in the prostate with the UMCU robot are feasible. (note)

MRI-guided robotic system for transperineal prostate interventions: proof of principle

Energy Technology Data Exchange (ETDEWEB)

Van den Bosch, Michiel R; Moman, Maaike R; Van Vulpen, Marco; Battermann, Jan J; Lagendijk, Jan J W; Moerland, Marinus A [Department of Radiotherapy, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht (Netherlands); Duiveman, Ed; Van Schelven, Leonard J [Medical Technology and Clinical Physics, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht (Netherlands); De Leeuw, Hendrik [Image Sciences Institute, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht (Netherlands)], E-mail: M.R.vandenBosch@umcutrecht.nl

2010-03-07

In this study, we demonstrate the proof of principle of the University Medical Center Utrecht (UMCU) robot dedicated to magnetic resonance imaging (MRI)-guided interventions in patients. The UMCU robot consists of polymers and non-ferromagnetic materials. For transperineal prostate interventions, it can be placed between the patient's legs inside a closed bore 1.5T MR scanner. The robot can manually be translated and rotated resulting in five degrees of freedom. It contains a pneumatically driven tapping device to automatically insert a needle stepwise into the prostate using a controller unit outside the scanning room. To define the target positions and to verify the needle insertion point and the needle trajectory, a high-resolution 3D balanced steady state free precession (bSSFP) scan that provides a T2/T1-weighted contrast is acquired. During the needle insertion fast 2D bSSFP images are generated to track the needle on-line. When the target position is reached, the radiation oncologist manually places a fiducial gold marker (small seed) at this location. In total two needle trajectories are used to place all markers. Afterwards, a high-resolution 3D bSSFP scan is acquired to visualize the fiducial gold markers. Four fiducial gold markers were placed transperineally into the prostate of a patient with a clinical stage T3 prostate cancer. In the generated scans, it was possible to discriminate the patient's anatomy, the needle and the markers. All markers were delivered inside the prostate. The procedure time was 1.5 h. This study proves that MRI-guided needle placement and seed delivery in the prostate with the UMCU robot are feasible. (note)

Spin fluctuations in EuS

International Nuclear Information System (INIS)

Hartmann, A.

1996-02-01

Demagnetization effects break the isotropy of spin waves. During spring 1995, Peter Boeni et al. performed polarized neutron measurements on EuS using the triple axis spectrometer IN14 at the ILL in Grenoble, in order to investigate the influence of dipolar interactions on the spin waves. In the following work the analysis of the experimental data is described. (author) 25 figs., 2 tabs., 9 refs

Search for Spin Filtering By Electron Tunneling Through Ferromagnetic EuS Barriers in Pbs

Science.gov (United States)

Figielski, T.; Morawski, A.; Wosinski, T.; Wrotek, S.; Makosa, A.; Lusakowska, E.; Story, T.; Sipatov, A. Yu.; Szczerbakow, A.; Grasza, K.;

Post-clip placement MRI following second-look US-guided core biopsy for suspicious lesions identified on breast MRI

Energy Technology Data Exchange (ETDEWEB)

Song, Sung Eun [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); Korea University Anam Hospital, Korea University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Cho, Nariya [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Seoul National University Medical Research Centre, Institute of Radiation Medicine, Seoul (Korea, Republic of); Han, Wonshik [Seoul National University Hospital, Department of Surgery, Seoul (Korea, Republic of)

2017-12-15

To evaluate whether the post-clip placement MRI following second-look ultrasound (US)-guided core biopsy is useful to confirm the adequate sampling of suspicious lesions identified on breast MRI. Between 2014 and 2016, 31 consecutive women with 34 suspicious lesions that had not been identified on previous mammography or US were detected using MRI. Among them, 26 women with 29 lesions (mean size 1.5 cm, range 0.5-5.8 cm) found by second-look US underwent US-guided biopsy, subsequent clip insertion and post-clip placement MRI. Five women with five lesions that were not found by second-look US underwent MRI-guided biopsy. The technical success rate and lesion characteristics were described. The technical success rate was 96.6% (28/29). One failure case was a benign, 1.1-cm non-mass enhancement. Of the 28 success cases, 23 (82.1%) were masses and 5 (17.9%) were non-mass enhancements; 17 (60.7%) were benign, 4 (14.3%) were high-risk and 7 (25.0%) were malignant lesions. The technical success rate was 100% (28/28) for masses and 83.3% (5/6) for non-mass enhancements. Post-clip placement MRI following US-guided biopsy is useful in confirming the adequate sampling of lesions identified on MRI. This method could be an alternative to MRI-guided biopsy for lesions visible on US. (orig.)

Post-clip placement MRI following second-look US-guided core biopsy for suspicious lesions identified on breast MRI

International Nuclear Information System (INIS)

Song, Sung Eun; Cho, Nariya; Han, Wonshik

2017-01-01

To evaluate whether the post-clip placement MRI following second-look ultrasound (US)-guided core biopsy is useful to confirm the adequate sampling of suspicious lesions identified on breast MRI. Between 2014 and 2016, 31 consecutive women with 34 suspicious lesions that had not been identified on previous mammography or US were detected using MRI. Among them, 26 women with 29 lesions (mean size 1.5 cm, range 0.5-5.8 cm) found by second-look US underwent US-guided biopsy, subsequent clip insertion and post-clip placement MRI. Five women with five lesions that were not found by second-look US underwent MRI-guided biopsy. The technical success rate and lesion characteristics were described. The technical success rate was 96.6% (28/29). One failure case was a benign, 1.1-cm non-mass enhancement. Of the 28 success cases, 23 (82.1%) were masses and 5 (17.9%) were non-mass enhancements; 17 (60.7%) were benign, 4 (14.3%) were high-risk and 7 (25.0%) were malignant lesions. The technical success rate was 100% (28/28) for masses and 83.3% (5/6) for non-mass enhancements. Post-clip placement MRI following US-guided biopsy is useful in confirming the adequate sampling of lesions identified on MRI. This method could be an alternative to MRI-guided biopsy for lesions visible on US. (orig.)

Intra-operative reliability of ShapeMatch cutting guide placement in total knee arthroplasty.

Science.gov (United States)

Clark, Gavin; Leong, Anthony; McEwen, Peter; Steele, Robert; Tran, Ton; Trivett, Adrian

2013-01-01

Custom cutting guides based on pre-operative imaging have been introduced for total knee arthroplasty (TKA). The aim of this prospective cohort study was to assess the reliability of repeated placement of custom cutting guides by multiple surgeons in a group of patients undergoing TKA. Custom cutting guides (ShapeMatch®, Stryker Orthopaedics) were designed from pre-operative MRI scans. The treating surgeon placed each guide on the femur and tibia of each patient three times without pinning the block. The three-dimensional position and orientation of the guide was measured for each repetition using a computer navigation system. The surgeon was blinded to the navigation system display. Data from 24 patients and 6 surgeons were analyzed. Intraclass correlation coefficients for all measurement parameters were in the range 0.889-0.997 (excellent), and all comparisons were statistically significant (p reliable.

Three-dimensional C-arm CT-guided transjugular intrahepatic portosystemic shunt placement: Feasibility, technical success and procedural time

Energy Technology Data Exchange (ETDEWEB)

Ketelsen, Dominik; Groezinger, Gerd; Maurer, Michael; Grosse, Ulrich; Horger, Marius; Nikolaou, Konstantin; Syha, Roland [University of Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany); Lauer, Ulrich M. [University of Tuebingen, Internal Medicine I, Department of Gastroenterology, Hepatology and Infectious disease, Tuebingen (Germany)

2016-12-15

Establishment of transjugular intrahepatic portosystemic shunts (TIPS) constitutes a standard procedure in patients suffering from portal hypertension. The most difficult step in TIPS placement is blind puncture of the portal vein. This study aimed to evaluate three-dimensional mapping of portal vein branches and targeted puncture of the portal vein. Twelve consecutive patients suffering from refractory ascites by liver cirrhosis were included in this retrospective study to evaluate feasibility, technical success and procedural time of C-arm CT-targeted puncture of the portal vein. As a control, 22 patients receiving TIPS placement with fluoroscopy-guided blind puncture were included to compare procedural time. Technical success could be obtained in 100 % of the study group (targeted puncture) and in 95.5 % of the control group (blind puncture). Appropriate, three-dimensional C-arm CT-guided mapping of the portal vein branches could be achieved in all patients. The median number of punctures in the C-arm CT-guided study group was 2 ± 1.3 punctures. Procedural time was significantly lower in the study group (14.8 ± 8.2 min) compared to the control group (32.6 ± 22.7 min) (p = 0.02). C-arm CT-guided portal vein mapping is technically feasible and a promising tool for TIPS placement resulting in a significant reduction of procedural time. (orig.)

Validation of deformable image registration algorithms on CT images of ex vivo porcine bladders with fiducial markers

NARCIS (Netherlands)

Wognum, S.; Heethuis, S. E.; Rosario, T.; Hoogeman, M. S.; Bel, A.

2014-01-01

The spatial accuracy of deformable image registration (DIR) is important in the implementation of image guided adaptive radiotherapy techniques for cancer in the pelvic region. Validation of algorithms is best performed on phantoms with fiducial markers undergoing controlled large deformations.

WE-AB-303-05: Breathing Motion of Liver Segments From Fiducial Tracking During Robotic Radiosurgery and Comparison with 4D-CT-Derived Fiducial Motion

International Nuclear Information System (INIS)

Sutherland, J; Pantarotto, J; Nair, V; Cook, G; Plourde, M; Vandervoort, E

2015-01-01

Purpose: To quantify respiratory-induced motion of liver segments using the positions of implanted fiducials during robotic radiosurgery. This study also compared fiducial motion derived from four-dimensional computed tomography (4D-CT) maximum intensity projections (MIP) with motion derived from imaging during treatment. Methods: Forty-two consecutive liver patients treated with liver ablative radiotherapy were accrued to an ethics approved retrospective study. The liver segment in which each fiducial resided was identified. Fiducial positions throughout each treatment fraction were determined using orthogonal kilovoltage images. Any data due to patient repositioning or motion was removed. Mean fiducial positions were calculated. Fiducial positions beyond two standard deviations of the mean were discarded and remaining positions were fit to a line segment using least squares minimization (LSM). For eight patients, fiducial motion was derived from 4D-CT MIPs by calculating the CT number weighted mean position of the fiducial on each slice and fitting a line segment to these points using LSM. Treatment derived fiducial trajectories were corrected for patient rotation and compared to MIP derived trajectories. Results: The mean total magnitude of fiducial motion across all liver segments in left-right, anteroposterior, and superoinferior (SI) directions were 3.0 ± 0.2 mm, 9.3 ± 0.4 mm, and 20.5 ± 0.5 mm, respectively. Differences in per-segment mean fiducial motion were found with SI motion ranging from 12.6 ± 0.8 mm to 22.6 ± 0.9 mm for segments 3 and 8, respectively. Large, varied differences between treatment and MIP derived motion at simulation were found with the mean difference for SI motion being 2.6 mm (10.8 mm standard deviation). Conclusion: The magnitude of liver fiducial motion was found to differ by liver segment. MIP derived liver fiducial motion differed from motion observed during treatment, implying that 4D-CTs may not accurately capture the

WE-AB-303-05: Breathing Motion of Liver Segments From Fiducial Tracking During Robotic Radiosurgery and Comparison with 4D-CT-Derived Fiducial Motion

Energy Technology Data Exchange (ETDEWEB)

Sutherland, J; Pantarotto, J; Nair, V; Cook, G; Plourde, M; Vandervoort, E [The Ottawa Hospital Cancer Centre, Ottawa, Ontario (Canada)

2015-06-15

Purpose: To quantify respiratory-induced motion of liver segments using the positions of implanted fiducials during robotic radiosurgery. This study also compared fiducial motion derived from four-dimensional computed tomography (4D-CT) maximum intensity projections (MIP) with motion derived from imaging during treatment. Methods: Forty-two consecutive liver patients treated with liver ablative radiotherapy were accrued to an ethics approved retrospective study. The liver segment in which each fiducial resided was identified. Fiducial positions throughout each treatment fraction were determined using orthogonal kilovoltage images. Any data due to patient repositioning or motion was removed. Mean fiducial positions were calculated. Fiducial positions beyond two standard deviations of the mean were discarded and remaining positions were fit to a line segment using least squares minimization (LSM). For eight patients, fiducial motion was derived from 4D-CT MIPs by calculating the CT number weighted mean position of the fiducial on each slice and fitting a line segment to these points using LSM. Treatment derived fiducial trajectories were corrected for patient rotation and compared to MIP derived trajectories. Results: The mean total magnitude of fiducial motion across all liver segments in left-right, anteroposterior, and superoinferior (SI) directions were 3.0 ± 0.2 mm, 9.3 ± 0.4 mm, and 20.5 ± 0.5 mm, respectively. Differences in per-segment mean fiducial motion were found with SI motion ranging from 12.6 ± 0.8 mm to 22.6 ± 0.9 mm for segments 3 and 8, respectively. Large, varied differences between treatment and MIP derived motion at simulation were found with the mean difference for SI motion being 2.6 mm (10.8 mm standard deviation). Conclusion: The magnitude of liver fiducial motion was found to differ by liver segment. MIP derived liver fiducial motion differed from motion observed during treatment, implying that 4D-CTs may not accurately capture the

Limited Role for Biliary Stent as Surrogate Fiducial Marker in Pancreatic Cancer: Stent and Intratumoral Fiducials Compared

Energy Technology Data Exchange (ETDEWEB)

Horst, Astrid van der, E-mail: a.vanderhorst@amc.uva.nl [Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands); Lens, Eelco; Wognum, Silvia; Jong, Rianne de [Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands); Hooft, Jeanin E. van [Department of Gastroenterology and Hepatology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands); Tienhoven, Geertjan van; Bel, Arjan [Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands)

2014-07-01

Purpose: Because of low soft-tissue contrast of cone beam computed tomography (CBCT), fiducial markers are often used for radiation therapy patient setup verification. For pancreatic cancer patients, biliary stents have been suggested as surrogate fiducials. Using intratumoral fiducials as standard for tumor position, this study aims to quantify the suitability of biliary stents for measuring interfractional and respiratory-induced position variations of pancreatic tumors. Methods and Materials: Eleven pancreatic cancer patients with intratumoral fiducials and a biliary stent were included in this study. Daily CBCT scans (243 in total) were registered with a reference CT scan, based on bony anatomy, on fiducial markers, and on the biliary stent, respectively. We analyzed the differences in tumor position (ie, markers center-of-mass position) among these 3 registrations. In addition, we measured for 9 patients the magnitude of respiratory-induced motion (MM) of the markers and of the stent on 4-dimensional CT (4DCT) and determined the difference between these 2 magnitudes (ΔMM). Results: The stent indicated tumor position better than bony anatomy in 67% of fractions; the absolute difference between the markers and stent registration was >5 mm in 46% of fractions and >10 mm in 20% of fractions. Large PTV margins (superior-inferior direction, >19 mm) would be needed to account for this interfractional position variability. On 4DCT, we found in superior-inferior direction a mean ΔMM of 0.5 mm (range, –2.6 to 4.2 mm). Conclusions: For respiratory-induced motion, the mean ΔMM is small, but for individual patients the absolute difference can be >4 mm. For interfractional position variations, a stent is, on average, a better surrogate fiducial than bony anatomy, but large PTV margins would still be required. Therefore, intratumoral fiducials are recommended for online setup verification for all pancreatic patients scheduled for radiation therapy, including

Genetic evolutionary taboo search for optimal marker placement in infrared patient setup

International Nuclear Information System (INIS)

Riboldi, M; Baroni, G; Spadea, M F; Tagaste, B; Garibaldi, C; Cambria, R; Orecchia, R; Pedotti, A

2007-01-01

In infrared patient setup adequate selection of the external fiducial configuration is required for compensating inner target displacements (target registration error, TRE). Genetic algorithms (GA) and taboo search (TS) were applied in a newly designed approach to optimal marker placement: the genetic evolutionary taboo search (GETS) algorithm. In the GETS paradigm, multiple solutions are simultaneously tested in a stochastic evolutionary scheme, where taboo-based decision making and adaptive memory guide the optimization process. The GETS algorithm was tested on a group of ten prostate patients, to be compared to standard optimization and to randomly selected configurations. The changes in the optimal marker configuration, when TRE is minimized for OARs, were specifically examined. Optimal GETS configurations ensured a 26.5% mean decrease in the TRE value, versus 19.4% for conventional quasi-Newton optimization. Common features in GETS marker configurations were highlighted in the dataset of ten patients, even when multiple runs of the stochastic algorithm were performed. Including OARs in TRE minimization did not considerably affect the spatial distribution of GETS marker configurations. In conclusion, the GETS algorithm proved to be highly effective in solving the optimal marker placement problem. Further work is needed to embed site-specific deformation models in the optimization process

Post-clip placement MRI following second-look US-guided core biopsy for suspicious lesions identified on breast MRI.

Science.gov (United States)

Song, Sung Eun; Cho, Nariya; Han, Wonshik

2017-12-01

To evaluate whether the post-clip placement MRI following second-look ultrasound (US)-guided core biopsy is useful to confirm the adequate sampling of suspicious lesions identified on breast MRI. Between 2014 and 2016, 31 consecutive women with 34 suspicious lesions that had not been identified on previous mammography or US were detected using MRI. Among them, 26 women with 29 lesions (mean size 1.5 cm, range 0.5-5.8 cm) found by second-look US underwent US-guided biopsy, subsequent clip insertion and post-clip placement MRI. Five women with five lesions that were not found by second-look US underwent MRI-guided biopsy. The technical success rate and lesion characteristics were described. The technical success rate was 96.6% (28/29). One failure case was a benign, 1.1-cm non-mass enhancement. Of the 28 success cases, 23 (82.1%) were masses and 5 (17.9%) were non-mass enhancements; 17 (60.7%) were benign, 4 (14.3%) were high-risk and 7 (25.0%) were malignant lesions. The technical success rate was 100% (28/28) for masses and 83.3% (5/6) for non-mass enhancements. Post-clip placement MRI following US-guided biopsy is useful in confirming the adequate sampling of lesions identified on MRI. This method could be an alternative to MRI-guided biopsy for lesions visible on US. • Post-clip MRI is useful for confirming adequate sampling of US-guided biopsy. • Post-clip MRI following US-guided biopsy revealed a 96.6 % technical success rate. • One technical failure case was a benign, 1.1-cm non-mass enhancement. • The technical success rate of US-guided biopsy for non-mass enhancements was 83.3 %.

Endoscopic Ultrasound-guided Drainage of Pancreatic Pseudocysts

DEFF Research Database (Denmark)

Ng, Pui Yung; Nytoft Rasmussen, Ditlev; Vilmann, Peter

2013-01-01

or by telephonic interview. RESULTS: A total of 61 procedures were performed. The symptoms that indicated drainage were abdominal pain (n = 43), vomiting (n = 7) and jaundice (n = 5). The procedure was technically successful in 57 of the 61 procedures (93%). The immediate complication rate was 5%. At a mean follow......-up of 45 weeks, the treatment success was 75%. The medium term complications appeared in 25% of cases, which included three cases each of stent clogging, stent migration, infection and six cases of recurrence. There was no mortality. CONCLUSION: EUS-guided drainage is an effective treatment for PPC...... with a successful outcome in most of patients. Most of the complications require minimal invasive surgical treatment or repeated EUS-guided drainage procedures....

Clinical results from first use of prostate stent as fiducial for radiotherapy of prostate cancer

Energy Technology Data Exchange (ETDEWEB)

Carl, Jesper; Nielsen, Jane (Dept. of Medical Physics, Dept. of Oncology, Aalborg Hospital, Aarhus Univ. Hospital, Aalborg (Denmark)), e-mail: jhc@rn.dk; Holmberg, Mats (Dept. of Oncology, Aalborg Hospital, Aarhus Univ. Hospital, Aalborg (Denmark)); Larsen, Erik Hoejkjaer; Fabrin, Knud (Dept. of Urology, Aalborg Hospital, Aarhus Univ. Hospital, Aalborg (Denmark)); Fisker, Rune V. (Dept. of Radiology, Aalborg Hospital, Aarhus Univ. Hospital, Aalborg (Denmark))

2011-05-15

Purpose. A clinical feasibility study using a removable prostate stent as fiducial for image-guided radiotherapy (IGRT) of localized prostate cancer (PC). Material and methods. The study included patients with local or locally advanced PC. The clinical target volume (CTV) was outlined on magnetic resonance (MR) images co-registered to planning computer tomography (CT) images. Daily online IGRT was delivered using the stent as fiducial. Risk of migration was estimated using multiple MR. Acute urinary toxicity was scored using the international prostate symptom score (IPSS). Late gastro-intestinal (GI) and genito-urinary (GU) toxicity was scored using the Radio Therapy Oncology Group (RTOG) score, biochemical failure (BF) was defined as an elevation of prostate specific antigen (PSA) above nadir plus 2 ng/ml after radiotherapy. Results. One hundred men were enrolled in the study. Ninety completed radiotherapy with the stent as fiducial. No migration of the stent was seen, but three cases of dislocation of the stent to the bladder were observed. Acute urinary toxicity based on IPSS was comparable to toxicity in patients who had gold markers (GM) as fiducials. Removal of the stent was associated with a high frequency of urinary retention. Late GI and GU toxicity and BF were comparable to those of other studies, but longer observation time is needed. Conclusions. This study reports the first clinical results of using a prostate stent as fiducial. No migration of the stent observed. Dislocation of the stent to the urinary bladder was observed in three cases, requiring removal of the stent and insertion of a new fiducial. Acute toxicity during radiotherapy evaluated from IPSS was comparable to toxicity in patients with GM. Removal of the stent was associated with a high frequency of post procedural urinary retention. Late toxicity and BF were comparable to those of other studies, though longer observation time is needed

Clinical results from first use of prostate stent as fiducial for radiotherapy of prostate cancer

International Nuclear Information System (INIS)

Carl, Jesper; Nielsen, Jane; Holmberg, Mats; Larsen, Erik Hoejkjaer; Fabrin, Knud; Fisker, Rune V.

2011-01-01

Purpose. A clinical feasibility study using a removable prostate stent as fiducial for image-guided radiotherapy (IGRT) of localized prostate cancer (PC). Material and methods. The study included patients with local or locally advanced PC. The clinical target volume (CTV) was outlined on magnetic resonance (MR) images co-registered to planning computer tomography (CT) images. Daily online IGRT was delivered using the stent as fiducial. Risk of migration was estimated using multiple MR. Acute urinary toxicity was scored using the international prostate symptom score (IPSS). Late gastro-intestinal (GI) and genito-urinary (GU) toxicity was scored using the Radio Therapy Oncology Group (RTOG) score, biochemical failure (BF) was defined as an elevation of prostate specific antigen (PSA) above nadir plus 2 ng/ml after radiotherapy. Results. One hundred men were enrolled in the study. Ninety completed radiotherapy with the stent as fiducial. No migration of the stent was seen, but three cases of dislocation of the stent to the bladder were observed. Acute urinary toxicity based on IPSS was comparable to toxicity in patients who had gold markers (GM) as fiducials. Removal of the stent was associated with a high frequency of urinary retention. Late GI and GU toxicity and BF were comparable to those of other studies, but longer observation time is needed. Conclusions. This study reports the first clinical results of using a prostate stent as fiducial. No migration of the stent observed. Dislocation of the stent to the urinary bladder was observed in three cases, requiring removal of the stent and insertion of a new fiducial. Acute toxicity during radiotherapy evaluated from IPSS was comparable to toxicity in patients with GM. Removal of the stent was associated with a high frequency of post procedural urinary retention. Late toxicity and BF were comparable to those of other studies, though longer observation time is needed

Clinical results from first use of prostate stent as fiducial for radiotherapy of prostate cancer.

Science.gov (United States)

Carl, Jesper; Nielsen, Jane; Holmberg, Mats; Larsen, Erik Hoejkjaer; Fabrin, Knud; Fisker, Rune V

2011-05-01

A clinical feasibility study using a removable prostate stent as fiducial for image-guided radiotherapy (IGRT) of localized prostate cancer (PC). The study included patients with local or locally advanced PC. The clinical target volume (CTV) was outlined on magnetic resonance (MR) images co-registered to planning computer tomography (CT) images. Daily online IGRT was delivered using the stent as fiducial. Risk of migration was estimated using multiple MR. Acute urinary toxicity was scored using the international prostate symptom score (IPSS). Late gastro-intestinal (GI) and genito-urinary (GU) toxicity was scored using the Radio Therapy Oncology Group (RTOG) score, biochemical failure (BF) was defined as an elevation of prostate specific antigen (PSA) above nadir plus 2 ng/ml after radiotherapy. One hundred men were enrolled in the study. Ninety completed radiotherapy with the stent as fiducial. No migration of the stent was seen, but three cases of dislocation of the stent to the bladder were observed. Acute urinary toxicity based on IPSS was comparable to toxicity in patients who had gold markers (GM) as fiducials. Removal of the stent was associated with a high frequency of urinary retention. Late GI and GU toxicity and BF were comparable to those of other studies, but longer observation time is needed. This study reports the first clinical results of using a prostate stent as fiducial. No migration of the stent observed. Dislocation of the stent to the urinary bladder was observed in three cases, requiring removal of the stent and insertion of a new fiducial. Acute toxicity during radiotherapy evaluated from IPSS was comparable to toxicity in patients with GM. Removal of the stent was associated with a high frequency of post procedural urinary retention. Late toxicity and BF were comparable to those of other studies, though longer observation time is needed.

Geometric programming facilities of EusLisp and assembly goal planner

International Nuclear Information System (INIS)

Matsui, Toshihiro; Sakane, Shigeyuki; Hirukawa, Hirohisa

1994-01-01

For robots in power plants to accomplish intelligent tasks such as maintenance, inspection, and assembly, the robots must have planning capabilities based on shape models of the environment. Such shape models are defined and manipulated by a program called a geometric modeler or a solid modeler. Although there are commercial solid modelers in the market, they are not always suitable for robotics research, since it is hard to integrate higher level planning functions which frequently access internal model representation. In order to accelerate advanced robotics research, we need a generic, extensible, efficient, and integration-oriented geometric modeler. After reviewing available modelers, we concluded that the object-oriented Lisp can be the best implementation language for solid modeling. The next section introduces the programming language, 'EusLisp', tuned for implementing a solid modeler for intelligent robot programming. The design philosophy and the structure and functions of EusLisp are stated. In the following sections, EusLisp's applications, i.e., viewpoint and light-source location planning, derivation of motion constraint, and assembly goal planning, are discussed. (J.P.N.)

Advances in the Management of Upper Gastrointestinal Subepithelial Tumor: Pathologic Diagnosis Using Endoscopy without Endoscopic Ultrasound-Guided Biopsy

Directory of Open Access Journals (Sweden)

Hang Lak Lee

2016-05-01

Full Text Available Until now, biopsy methods for subepithelial tumors (SETs have focused on endoscopic ultrasound (EUS-guided biopsy; however, these methods have several limitations. We devised a simple method for pathologic diagnosis of SETs. SETs are occasionally diagnosed during endoscopy, and lesions are generally small and asymptomatic. It can be challenging to decide on a management plan for large asymptomatic SETs. EUS imaging provides information regarding the size, layer, and echo pattern of the lesions. Patient management plans have traditionally been determined based on EUS images, whereby the endoscopist chooses to either monitor or remove the tumor. However, EUS alone cannot diagnose and evaluate upper gastrointestinal SETs with high accuracy. As sufficient tissue samples are required for the accurate diagnosis of SETs, EUS-guided biopsy techniques such as EUS fine-needle aspiration and trucut biopsy are currently used. However, these methods have a relatively low diagnostic accuracy and do not always provide information upon immunohistochemical staining. Endoscopists can easily detect a submucosal mass after creating an iatrogenic mucosal ulcer, after which tissue sampling is performed by using endoscopic biopsy. Furthermore, pathologic results can differentiate between benign and premalignant lesions. Here, we introduce a simple method for the pathologic diagnosis of SETs.

Reliability of implant placement after virtual planning of implant positions using cone beam CT data and surgical (guide) templates.

Science.gov (United States)

Nickenig, Hans-Joachim; Eitner, Stephan

2007-01-01

We assessed the reliability of implant placement after virtual planning of implant positions using cone-beam CT data and surgical guide templates. A total of 102 patients (250 implants, 55.4% mandibular; mean patient age, 40.4 years) who had undergone implant treatment therapy in an armed forces dental clinic (Cologne, Germany) between July 1, 2005 and December 1, 2005. They were treated with a system that allows transfer of virtual planning to surgical guide templates. Only in eight cases the surgical guides were not used because a delayed implant placement was necessary. In four posterior mandibular cases, handling was limited because of reduced interocclusal distance, requiring 50% shortening of the drill guides. The predictability of implant size was high: only one implant was changed to a smaller diameter (because of insufficient bone). In all cases, critical anatomical structures were protected and no complications were detected in postoperative panoramic radiographs. In 58.1% (147) of the 250 implants, a flapless surgery plan was realized. Implant placement after virtual planning of implant positions using cone beam CT data and surgical templates can be reliable for preoperative assessment of implant size, position, and anatomical complications. It is also indicative of cases amenable to flapless surgery.

A serious game for learning ultrasound-guided needle placement skills.

Science.gov (United States)

Chan, Wing-Yin; Qin, Jing; Chui, Yim-Pan; Heng, Pheng-Ann

2012-11-01

Ultrasound-guided needle placement is a key step in a lot of radiological intervention procedures such as biopsy, local anesthesia and fluid drainage. To help training future intervention radiologists, we develop a serious game to teach the skills involved. We introduce novel techniques for realistic simulation and integrate game elements for active and effective learning. This game is designed in the context of needle placement training based on the some essential characteristics of serious games. Training scenarios are interactively generated via a block-based construction scheme. A novel example-based texture synthesis technique is proposed to simulate corresponding ultrasound images. Game levels are defined based on the difficulties of the generated scenarios. Interactive recommendation of desirable insertion paths is provided during the training as an adaptation mechanism. We also develop a fast physics-based approach to reproduce the shadowing effect of needles in ultrasound images. Game elements such as time-attack tasks, hints and performance evaluation tools are also integrated in our system. Extensive experiments are performed to validate its feasibility for training.

A novel lumen-apposing metal stent for endoscopic ultrasound-guided drainage of pancreatic fluid collections

DEFF Research Database (Denmark)

Walter, Daisy; Will, Uwe; Sanchez-Yague, Andres

2015-01-01

BACKGROUND AND STUDY AIMS: A novel large-diameter, lumen-apposing, self-expanding metal stent with bilateral flanges was recently developed for endoscopic ultrasound (EUS)-guided transmural drainage of symptomatic pancreatic fluid collections (PFCs). The aim of this study was to evaluate the effi......BACKGROUND AND STUDY AIMS: A novel large-diameter, lumen-apposing, self-expanding metal stent with bilateral flanges was recently developed for endoscopic ultrasound (EUS)-guided transmural drainage of symptomatic pancreatic fluid collections (PFCs). The aim of this study was to evaluate...

Automated Identification of Fiducial Points on 3D Torso Images

Directory of Open Access Journals (Sweden)

Manas M. Kawale

2013-01-01

Full Text Available Breast reconstruction is an important part of the breast cancer treatment process for many women. Recently, 2D and 3D images have been used by plastic surgeons for evaluating surgical outcomes. Distances between different fiducial points are frequently used as quantitative measures for characterizing breast morphology. Fiducial points can be directly marked on subjects for direct anthropometry, or can be manually marked on images. This paper introduces novel algorithms to automate the identification of fiducial points in 3D images. Automating the process will make measurements of breast morphology more reliable, reducing the inter- and intra-observer bias. Algorithms to identify three fiducial points, the nipples, sternal notch, and umbilicus, are described. The algorithms used for localization of these fiducial points are formulated using a combination of surface curvature and 2D color information. Comparison of the 3D coordinates of automatically detected fiducial points and those identified manually, and geodesic distances between the fiducial points are used to validate algorithm performance. The algorithms reliably identified the location of all three of the fiducial points. We dedicate this article to our late colleague and friend, Dr. Elisabeth K. Beahm. Elisabeth was both a talented plastic surgeon and physician-scientist; we deeply miss her insight and her fellowship.

Percutaneous subclavian artery stent-graft placement following failed ultrasound guided subclavian venous access

Directory of Open Access Journals (Sweden)

Szkup Peter

2006-05-01

Full Text Available Abstract Background Ultrasound guidance for central and peripheral venous access has been proven to improve success rates and reduce complications of venous cannulation. Appropriately trained and experienced operators add significantly to diminished patient morbidity related to venous access procedures. We discuss a patient who required an arterial stent-graft to prevent arterial hemorrhage following inadvertent cannulation of the proximal, ventral, right subclavian artery related to unsuccessful ultrasound guided access of the subclavian vein. Case presentation During pre-operative preparation for aortic valve replacement and aorto-coronary bypass surgery an anesthetist attempted ultrasound guided venous access. The ultrasound guided attempt to access the right jugular vein failed and the ultrasound guided attempt at accessing the subclavian vein resulted in inappropriate placement of an 8.5 F sheath in the arterial system. Following angiographic imaging and specialist consultations, an arterial stent-graft was deployed in the right subclavian artery rather than perform an extensive anterior chest wall resection and dissection to extract the arterial sheath. The patient tolerated the procedure, without complication, despite occlusion of the right internal mammary artery and the right vertebral artery. There were no neurologic sequelae. There was no evidence of hemorrhage after subclavian artery sheath extraction and stent-graft implantation. Conclusion The attempted ultrasound guided puncture of the subclavian vein resulted in placement of an 8.5 F subclavian artery catheter. Entry of the catheter into the proximal subclavian artery beneath the medial clavicle, the medial first rib and the manubrium suggests that the operator, most likely, did not directly visualize the puncture needle enter the vessel with the ultrasound. The bones of the anterior chest impede the ultrasound beam and the vessels in this area would not be visible to ultrasound

Determination of optimal ultrasound planes for the initialisation of image registration during endoscopic ultrasound-guided procedures.

Science.gov (United States)

Bonmati, Ester; Hu, Yipeng; Gibson, Eli; Uribarri, Laura; Keane, Geri; Gurusami, Kurinchi; Davidson, Brian; Pereira, Stephen P; Clarkson, Matthew J; Barratt, Dean C

2018-06-01

Navigation of endoscopic ultrasound (EUS)-guided procedures of the upper gastrointestinal (GI) system can be technically challenging due to the small fields-of-view of ultrasound and optical devices, as well as the anatomical variability and limited number of orienting landmarks during navigation. Co-registration of an EUS device and a pre-procedure 3D image can enhance the ability to navigate. However, the fidelity of this contextual information depends on the accuracy of registration. The purpose of this study was to develop and test the feasibility of a simulation-based planning method for pre-selecting patient-specific EUS-visible anatomical landmark locations to maximise the accuracy and robustness of a feature-based multimodality registration method. A registration approach was adopted in which landmarks are registered to anatomical structures segmented from the pre-procedure volume. The predicted target registration errors (TREs) of EUS-CT registration were estimated using simulated visible anatomical landmarks and a Monte Carlo simulation of landmark localisation error. The optimal planes were selected based on the 90th percentile of TREs, which provide a robust and more accurate EUS-CT registration initialisation. The method was evaluated by comparing the accuracy and robustness of registrations initialised using optimised planes versus non-optimised planes using manually segmented CT images and simulated ([Formula: see text]) or retrospective clinical ([Formula: see text]) EUS landmarks. The results show a lower 90th percentile TRE when registration is initialised using the optimised planes compared with a non-optimised initialisation approach (p value [Formula: see text]). The proposed simulation-based method to find optimised EUS planes and landmarks for EUS-guided procedures may have the potential to improve registration accuracy. Further work will investigate applying the technique in a clinical setting.

Accurate guide wire of lag screw placement in the intertrochanteric fractures: a technical note.

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Li, Jiang; Wang, Liao; Li, Xiaodong; Feng, Kai; Tang, Jian; Wang, Xiaoqing

2017-09-01

Cephalomedullary fixations are commonly used in the treatment of intertrochanteric fractures. In clinical practice, one of the difficulties is when we exit the guide wire in a wrong position of femoral neck and insert near the hole again, the guide wire often flow into the previous track. This study develops a surgical technique to direct the guide wire to slip away the previous track and slip into a right position. When guide wire is exited to the cortex of femoral, we let the wire in and out at the cortical layer for several times to enlarge the entry hole. After that, electric drill is inverted, rubbed and entered slowly at a right angle. When guide wire encountered new resistance, the electric drill is turned back instantly. This technique can help trauma and orthopedic surgeons to obtain precision placement of the lag screw after the first try is failed.

Residual translational and rotational errors after kV X-ray image-guided correction of prostate location using implanted fiducials

International Nuclear Information System (INIS)

Wust, Peter; Graf, Reinhold; Boehmer, Dirk; Budach, Volker

2010-01-01

Purpose: To evaluate the residual errors and required safety margins after stereoscopic kilovoltage (kV) X-ray target localization of the prostate in image-guided radiotherapy (IGRT) using internal fiducials. Patients and Methods: Radiopaque fiducial markers (FMs) have been inserted into the prostate in a cohort of 33 patients. The ExacTrac/Novalis Body trademark X-ray 6d image acquisition system (BrainLAB AG, Feldkirchen, Germany) was used. Corrections were performed in left-right (LR), anterior-posterior (AP), and superior-inferior (SI) direction. Rotational errors around LR (x-axis), AP (y) and SI (z) have been recorded for the first series of nine patients, and since 2007 for the subsequent 24 patients in addition corrected in each fraction by using the Robotic Tilt Module trademark and Varian Exact Couch trademark. After positioning, a second set of X-ray images was acquired for verification purposes. Residual errors were registered and again corrected. Results: Standard deviations (SD) of residual translational random errors in LR, AP, and SI coordinates were 1.3, 1.7, and 2.2 mm. Residual random rotation errors were found for lateral (around x, tilt), vertical (around y, table), and longitudinal (around z, roll) and of 3.2 , 1.8 , and 1.5 . Planning target volume (PTV)-clinical target volume (CTV) margins were calculated in LR, AP, and SI direction to 2.3, 3.0, and 3.7 mm. After a second repositioning, the margins could be reduced to 1.8, 2.1, and 1.8 mm. Conclusion: On the basis of the residual setup error measurements, the margin required after one to two online X-ray corrections for the patients enrolled in this study would be at minimum 2 mm. The contribution of intrafractional motion to residual random errors has to be evaluated. (orig.)

Residual translational and rotational errors after kV X-ray image-guided correction of prostate location using implanted fiducials

Energy Technology Data Exchange (ETDEWEB)

Wust, Peter [Dept. of Radiation Oncology, Charite - Univ. Medicine Berlin, Campus Virchow-Klinikum, Berlin (Germany); Graf, Reinhold; Boehmer, Dirk; Budach, Volker

2010-10-15

Purpose: To evaluate the residual errors and required safety margins after stereoscopic kilovoltage (kV) X-ray target localization of the prostate in image-guided radiotherapy (IGRT) using internal fiducials. Patients and Methods: Radiopaque fiducial markers (FMs) have been inserted into the prostate in a cohort of 33 patients. The ExacTrac/Novalis Body trademark X-ray 6d image acquisition system (BrainLAB AG, Feldkirchen, Germany) was used. Corrections were performed in left-right (LR), anterior-posterior (AP), and superior-inferior (SI) direction. Rotational errors around LR (x-axis), AP (y) and SI (z) have been recorded for the first series of nine patients, and since 2007 for the subsequent 24 patients in addition corrected in each fraction by using the Robotic Tilt Module trademark and Varian Exact Couch trademark. After positioning, a second set of X-ray images was acquired for verification purposes. Residual errors were registered and again corrected. Results: Standard deviations (SD) of residual translational random errors in LR, AP, and SI coordinates were 1.3, 1.7, and 2.2 mm. Residual random rotation errors were found for lateral (around x, tilt), vertical (around y, table), and longitudinal (around z, roll) and of 3.2 , 1.8 , and 1.5 . Planning target volume (PTV)-clinical target volume (CTV) margins were calculated in LR, AP, and SI direction to 2.3, 3.0, and 3.7 mm. After a second repositioning, the margins could be reduced to 1.8, 2.1, and 1.8 mm. Conclusion: On the basis of the residual setup error measurements, the margin required after one to two online X-ray corrections for the patients enrolled in this study would be at minimum 2 mm. The contribution of intrafractional motion to residual random errors has to be evaluated. (orig.)

Nonfluoroscopic endoscopic ultrasound-guided transmural drainage of pancreatic pseudocysts at atypical locations

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Surinder Singh Rana

2016-01-01

Full Text Available Background: Pancreatic pseudocysts (PP at atypical locations are a therapeutic challenge and are usually managed surgically. Objective: We evaluated safety and efficacy of nonfluoroscopic endoscopic ultrasound (NF-EUS-guided transmural drainage in the management of PP at atypical locations. Patients and Methods: Retrospective analysis of 11 patients (all males; age range: 28-46 years with PP at atypical locations who were treated with NF-EUS-guided transmural drainage during the last 18 months was done. Results: Four patients had intra/peri-splenic, three patients had mediastinal, three patients had intrahepatic, and one patient had renal PP. Nine patients had chronic pancreatitis whereas two patients had acute pancreatitis. Alcohol was the etiology of pancreatitis in ten patients. The size of PP ranged from 4 to 10 cm. All patients had abdominal pain, and two patients had fever whereas one patient with mediastinal PP also had dysphagia. NF-EUS-guided transmural drainage could be done successfully in all patients. 7 Fr transmural stent (s was/were placed in six patients whereas single-time complete aspiration of PP was done in five patients. On endoscopic retrograde pancreatography, six patients had partial duct disruption whereas five patients had complete disruption. Bridging transpapillary stent (5 Fr was placed in all patients with partial disruption. All PP healed in 10/11 (91% patients within 2-4 weeks, and there has been no recurrence in 9 of these patients during a follow-up period of 4-18 months. One patient with splenic PP needed surgery for gastrointestinal bleed. Conclusion: PP at atypical locations can be effectively and safely treated with NF-EUS-guided transmural drainage.

Training and certification in endobronchial ultrasound-guided transbronchial needle aspiration

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Konge, Lars; Nayahangan, Leizl Joy; Clementsen, Paul Frost

2017-01-01

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) plays a key role in the staging of lung cancer, which is crucial for allocation to surgical treatment. EBUS-TBNA is a complicated procedure and simulation-based training is helpful in the first part of the long learning curve prior to performing the procedure on actual patients. New trainees should follow a structured training programme consisting of training on simulators to proficiency as assessed with a validated test followed by supervised practice on patients. The simulation-based training is superior to the traditional apprenticeship model and is recommended in the newest guidelines. EBUS-TBNA and oesophageal ultrasound-guided fine needle aspiration (EUS-FNA or EUS-B-FNA) are complementary to each other and the combined techniques are superior to either technique alone. It is logical to learn and to perform the two techniques in combination, however, for lung cancer staging solely EBUS-TBNA simulators exist, but hopefully in the future simulation-based training in EUS will be possible. PMID:28840013

Irregular echogenic foci representing coagulation necrosis: a useful but perhaps under-recognized EUS echo feature of malignant lymph node invasion.

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Bhutani, Manoop S; Saftoiu, Adrian; Chaya, Charles; Gupta, Parantap; Markowitz, Avi B; Willis, Maurice; Kessel, Ivan; Sharma, Gulshan; Zwischenberger, Joseph B

2009-06-01

Coagulation necrosis has been described in malignant lymph nodes. Our aim was to determine if coagulation necrosis in mediastinal lymph nodes imaged by EUS could be used as a useful echo feature for predicting malignant invasion. Patients with known or suspected lung cancer who had undergone mediastinal lymph node staging by EUS. Tertiary Care university hospital. An expert endosonographer blinded to the final diagnosis, reviewed the archived digital EUS images of lymph nodes prior to being sampled by FNA. LNs positive for malignancy by FNA were included. The benign group included lymph node images with either negative EUS-FNA or lymph nodes imaged by EUS but not subjected to EUS-FNA, with surgical correlation of their benign nature. 24 patients were included. 8 patients were found to have coagulation necrosis. 7/8 patients had positive result for malignancy by EUS-FNA. One patient determined to have coagulation necrosis had a non-malignant diagnosis indicating a false positive result. 16 patients had no coagulation necrosis. In 6 patients with no coagulation necrosis, the final diagnosis was malignant and in the remaining 10 cases, the final diagnosis was benign. For coagulation necrosis as an echo feature for malignant invasion, sensitivity was 54%, specificity was 91%, positive predictive value was 88%, negative predictive value was 63% and accuracy was 71%. Coagulation necrosis is a useful echo feature for mediastinal lymph node staging by EUS.

Electrocautery vs non-electrocautery dilation catheters in endoscopic ultrasonography-guided pancreatic fluid collection drainage

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Kitamura, Katsuya; Yamamiya, Akira; Ishii, Yu; Nomoto, Tomohiro; Honma, Tadashi; Yoshida, Hitoshi

2016-01-01

AIM: To investigate the safety and utility of an electrocautery dilation catheter for endoscopic ultrasonography (EUS)-guided pancreatic fluid collection drainage. METHODS: A single-center, exploratory, retrospective study was conducted between August 2010 and August 2014. This study was approved by the Medical Ethics Committee of our institution. Informed, written consent was obtained from each patient prior to the procedure. The subjects included 28 consecutive patients who underwent EUS-guided transmural drainage (EUS-TD) for symptomatic pancreatic and peripancreatic fluid collections (PFCs) by fine needle aspiration using a 19-gauge needle. These patients were retrospectively divided into two groups based on the use of an electrocautery dilation catheter as a fistula dilation device; 15 patients were treated with an electrocautery dilation catheter (electrocautery group), and 13 patients were treated with a non-electrocautery dilation catheter (non-electrocautery group). We evaluated the technical and clinical successes and the adverse events associated with EUS-TD for the treatment of PFCs between the two groups. RESULTS: There were no significant differences in age, sex, type, location and diameter of PFCs between the groups. Thirteen patients (87%) in the electrocautery group and 10 patients (77%) in the non-electrocautery group presented with infected PFCs. The technical success rates of EUS-TD for the treatment of PFCs were 100% (15/15) and 100% (13/13) for the electrocautery and the non-electrocautery groups, respectively. The clinical success rates of EUS-TD for the treatment of PFCs were 67% (10/15) and 69% (9/13) for the electrocautery and the non-electrocautery groups, respectively (P = 0.794). The procedure time of EUS-TD for the treatment of PFCs in the electrocautery group was significantly shorter than that of the non-electrocautery group (mean ± SD: 30 ± 12 min vs 52 ± 20 min, P electrocautery and the non-electrocautery groups, respectively (P

Induced spin-polarization of EuS at room temperature in Ni/EuS multilayers

Energy Technology Data Exchange (ETDEWEB)

Poulopoulos, P., E-mail: poulop@upatras.gr [Laboratory of High-Tech Materials, School of Engineering, University of Patras, 26504 Patras (Greece); Materials Science Department, University of Patras, 26504 Patras (Greece); Goschew, A.; Straub, A.; Fumagalli, P. [Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin-Dahlem (Germany); Kapaklis, V.; Wolff, M. [Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala (Sweden); Delimitis, A. [Chemical Process and Energy Resources Institute (CPERI), Centre for Research and Technology Hellas (CERTH), 57001 Thermi, Thessaloniki (Greece); Wilhelm, F.; Rogalev, A. [European Synchrotron Radiation Facility (ESRF), B.P.220, 38043 Grenoble (France); Pappas, S. D. [Laboratory of High-Tech Materials, School of Engineering, University of Patras, 26504 Patras (Greece); Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala (Sweden)

2014-03-17

Ni/EuS multilayers with excellent multilayer sequencing are deposited via e-beam evaporation on the native oxide of Si(100) wafers at 4 × 10{sup −9} millibars. The samples have very small surface and interface roughness and show sharp interfaces. Ni layers are nanocrystalline 4–8 nm thick and EuS layers are 2–4 nm thick and are either amorphous or nanocrystalline. Unlike for Co/EuS multilayers, all Eu ions are in divalent (ferromagnetic) state. We show a direct antiferromagnetic coupling between EuS and Ni layers. At room temperature, the EuS layers are spin-polarized due to the proximity of Ni. Therefore, Ni/EuS is a candidate for room-temperature spintronics applications.

Five-year follow-up using a prostate stent as fiducial in image-guided radiotherapy of prostate cancer.

Science.gov (United States)

Carl, Jesper; Sander, Lotte

2015-06-01

To report results from the five-year follow-up on a previously reported study using image-guided radiotherapy (IGRT) of localized or locally advanced prostate cancer (PC) and a removable prostate stent as fiducial. Patients with local or locally advanced PC were treated using five-field 3D conformal radiotherapy (3DRT). The clinical target volumes (CTV) were treated to 78 Gy in 39 fractions using daily on-line image guidance (IG). Late genito-urinary (GU) and gastro-intestinal (GI) toxicities were scored using the radiotherapy oncology group (RTOG) score and the common toxicity score of adverse events (CTC) score. Urinary symptoms were also scored using the international prostate symptom score (IPSS). Median observation time was 5.4 year. Sixty-two of the 90 patients from the original study cohort were eligible for toxicity assessment. Overall survival, cancer-specific survival and biochemical freedom from failure were 85%, 96% and 80%, respectively at five years after radiotherapy. Late toxicity GU and GI RTOG scores≥2 were 5% and 0%. Comparing pre- and post-radiotherapy IPSS scores indicate that development in urinary symptoms after radiotherapy may be complex. Prostate image-guided radiotherapy using a prostate stent demonstrated survival data comparable with recently published data. GU and GI toxicities at five-year follow-up were low and comparable to the lowest toxicity rates reported. These findings support that the precision of the prostate stent technique is at least as good as other techniques. IPSS revealed a complex development in urinary symptoms after radiotherapy.

Safe and successful endoscopic initial treatment and long-term eradication of gastric varices by endoscopic ultrasound-guided Histoacryl (N-butyl-2-cyanoacrylate) injection

OpenAIRE

Gubler, Christoph; Bauerfeind, Peter

2014-01-01

OBJECTIVE: Optimal endoscopic treatment of gastric varices is still not standardized nowadays. Actively bleeding varices may prohibit a successful endoscopic injection therapy of Histoacryl® (N-butyl-2-cyanoacrylate). Since 2006, we have treated gastric varices by standardized endoscopic ultrasound (EUS) guided Histoacryl injection therapy without severe adverse events. MATERIAL AND METHODS: We present a large single-center cohort over 7 years with a standardized EUS-guided sclerotherapy o...

Role of endoscopic ultrasound-guided fine-needle aspiration in adrenal lesions: analysis of 32 patients

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Rakesh K Gupta

2018-01-01

Full Text Available Objective: Endoscopic ultrasound-guided fine-needle aspiration cytology (EUS-FNAC is a precise and safe technique that provides both radiological and pathological diagnosis with a better diagnostic yield and minimal adverse events. EUS-FNAC led to the remarkable increase in the detection rate of incidentaloma found during radiologic staging or follow-up in various malignancy or unrelated conditions. Aims: We did this preliminary study with an aim to evaluate the role of EUS-FNA in diagnosing and classifying adrenal lesions, clinical impact, and compare the outcome with the previously published literature. Materials and Methods: We included 32 consecutive cases (both retrospective and prospective of EUS-guided adrenal aspirate performed over a period of 3.3 years. The indications for the aspirate in decreasing order were metastasis (most common carcinoma gall bladder > primary adrenal mass > disseminated tuberculosis > pyrexia of unknown origin. On EUS, 28 cases revealed space occupying lesion or mass (two cases bilateral and four cases revealed diffuse enlargement (two cases bilateral with a mean size of 21 mm. Results: The cytology reports were benign adrenal aspirate (43.8%, metastatic adenocarcinoma (15.6%, histoplasmosis (9.4%, tuberculosis (9.4%, round cell tumor (6.2%, adrenocortical carcinoma (3.1%, and descriptive (3.1%. Three cases (9.4% yielded inadequate sample. The TNM staging was altered in 22.23% of the cases by result of adrenal aspirate. Conclusions: EUS-FNA of the adrenal gland is a safe, quick, and sensitive and real-time diagnostic technique, which requires an integrated approach of clinician, endoscopist, and cytopathologist for high precision in diagnosis. Although the role of EUS-FNA for right adrenal is not much described, we found adequate sample yield in all the four patients that underwent the procedure.

Nasogastric tube placement with video-guided laryngoscope: A manikin simulator study.

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Lee, Xiao-Lun; Yeh, Li-Chun; Jin, Yau-Dung; Chen, Chun-Chih; Lee, Ming-Ho; Huang, Ping-Wun

2017-08-01

This study aimed to investigate video-guided laryngoscopy for nasogastric tube placement. This was an observational comparative study performed in a hospital. The participants included volunteers from the medical staff (physicians and nurses) experienced with nasogastric intubation, and non-medical staff (medical students, pharmacists and emergent medical technicians) with knowledge of nasogastric intubation but lacking procedural experience. Medical and non-medical hospital staff performed manual, laryngoscope-assisted and video-guided laryngoscope nasogastric intubation both in the presence and in the absence of an endotracheal tube, using a manikin. Nasogastric intubation times were compared between groups and methods. Using the video-guided laryngoscope resulted in a significantly shorter intubation time compared to the other 2 methods, both with and without an endotracheal tube, for the medical and non-medical staff alike (all p guided laryngoscope without endotracheal intubation, direct laryngoscope with endotracheal intubation and video-guided laryngoscope with endotracheal intubation compared to manual intubation without endotracheal intubation (0.49, 0.63 and 0.72 vs. 5.63, respectively, p ≤ 0.008). For non-medical staff, nasogastric intubation time was significantly shorter using video-guided laryngoscope without endotracheal intubation, direct laryngoscope with endotracheal intubation and video-guided laryngoscope with endotracheal intubation compared to manual intubation without endotracheal intubation (1.67, 1.58 and 0.95 vs. 6.9, respectively, p ≤ 0.002). And mean nasogastric intubation time for video-guided laryngoscope endotracheal intubation was significantly shorter for medical staff than for non-medical staff (0.49 vs. 1.67 min, respectively, p = 0.041). Video-guided laryngoscope reduces nasogastric intubation time compared to manual and direct laryngoscope intubation, which promotes a consistent technique when performed by

Comparison of diagnostic yield of endoscopic ultrasound-guided fine-needle aspiration cytology and cell block in solid lesions

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Avinash Bhat Balekuduru

2017-01-01

Full Text Available Background and Aim: Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA is a procedure of choice for the diagnostic evaluation of submucosal and periluminal lesions. Tissue sample can be obtained by EUS-FNA cytology (FNAC or cell block (CB. The aim of the present study is to compare diagnostic yield of EUS-FNA CB and cytology in the absence of onsite pathologist following a protocol-based EUS-FNA approach in solid lesions. Patients and Methods: Participants who underwent EUS-FNA at our center for solid submucosal or periluminal lesions (pancreas, lymph node, and liver between 2014 and 2016 were included, retrospectively. The indication for the procedure along with the clinical and other investigation details and the final etiological diagnosis were recorded on uniform structured data forms. The diagnostic yield of cytology and CB were compared using McNemar's test. The P < 0.05 was considered statistically significant. Results: EUS-FNA for solid lesion was performed in 130 lesions in 101 patients during the study period. Their mean age was 52.5 ± 12 years and 42.5% were female. Pancreatic masses were the most common lesions (37.7% followed by lymph nodes (36.9%. Submucosal lesions (17.7% and liver lesions (7.7% accounted for rest of the cases. The overall diagnostic yield for EUS-FNAC (70% and CB (74.6% was not significantly different (P = 0.3 and their combined yield was 85.3%. For the 23 patients with submucosal lesion, diagnostic yield of CB (82.6% was significantly better than cytology (47.8%, P = 0.04. Conclusions: EUS-guided CB has better yield compared to cytology in gastrointestinal submucosal lesions. The combination of CB with cytology improves the overall yield of the procedure; and hence, they should be considered complimentary rather than alternatives.

High Retention and Safety of Percutaneously Implanted Endovascular Embolization Coils as Fiducial Markers for Image-Guided Stereotactic Ablative Radiotherapy of Pulmonary Tumors

International Nuclear Information System (INIS)

Hong, Julian C.; Yu Yao; Rao, Aarti K.; Dieterich, Sonja; Maxim, Peter G.; Le, Quynh-Thu; Diehn, Maximilian; Sze, Daniel Y.; Kothary, Nishita; Loo, Billy W.

2011-01-01

Purpose: To compare the retention rates of two types of implanted fiducial markers for stereotactic ablative radiotherapy (SABR) of pulmonary tumors, smooth cylindrical gold 'seed' markers ('seeds') and platinum endovascular embolization coils ('coils'), and to compare the complication rates associated with the respective implantation procedures. Methods and Materials: We retrospectively analyzed the retention of percutaneously implanted markers in 54 consecutive patients between January 2004 and June 2009. A total of 270 markers (129 seeds, 141 coils) were implanted in or around 60 pulmonary tumors over 59 procedures. Markers were implanted using a percutaneous approach under computed tomography (CT) guidance. Postimplantation and follow-up imaging studies were analyzed to score marker retention relative to the number of markers implanted. Markers remaining near the tumor were scored as retained. Markers in a distant location (e.g., pleural space) were scored as lost. CT imaging artifacts near markers were quantified on radiation therapy planning scans. Results: Immediately after implantation, 140 of 141 coils (99.3%) were retained, compared to 110 of 129 seeds (85.3%); the difference was highly significant (p < 0.0001). Of the total number of lost markers, 45% were reported lost during implantation, but 55% were lost immediately afterwards. No additional markers were lost on longer-term follow-up. Implanted lesions were peripherally located for both seeds (mean distance, 0.33 cm from pleural surface) and coils (0.34 cm) (p = 0.96). Incidences of all pneumothorax (including asymptomatic) and pneumothorax requiring chest tube placement were lower in implantation of coils (23% and 3%, respectively) vs. seeds (54% and 29%, respectively; p = 0.02 and 0.01). The degree of CT artifact was similar between marker types. Conclusions: Retention of CT-guided percutaneously implanted coils is significantly better than that of seed markers. Furthermore, implanting coils is at

Extra Luminal Entrapment of Guide Wire; A Rare Complication of Central Venous Catheter Placement in Right Internal Jugular Vein

OpenAIRE

Ansari, Md Abu Masud; Kumar, Naveen; Kumar, Shailesh; Kumari, Sarita

2016-01-01

Central venous Catheterization (CVC) is a commonly performed procedure for venous access. It is associated with several complications. We report a rare case of extra luminal entrapment of guide wire during CVC placement in right jugular vein. We report a case of 28 years old female patient presented in our emergency with history of entrapped guide wire in right side of neck during CVC. X-ray showed coiling of guide wire in neck. CT Angiography showed guide wire coursing in between common caro...

Endoscopic ultrasound-guided evaluation of the pleura and cases of pleural effusion.

Science.gov (United States)

Sharma, Malay; Rameshbabu, Chittapuram Srinivasan

2017-01-01

The most efficient and cost-effective approach for the diagnosis of pleural exudates remains uncertain and is a subject of controversy. Essential factors to be considered include the respective diagnostic yields of thoracocentesis, closed pleural biopsy, and thoracoscopy. The role of endoscopic ultrasound (EUS) of the esophagus as a modality for the evaluation of pleural exudates has not yet been evaluated. The applied anatomy of the pleura has been discussed. The techniques involved in the EUS imaging of different aspects of the pleura in normal cases and in cases with pleural effusion are elaborated. The practical application of this knowledge can be useful in EUS-guided sampling of the pleural wall, pleural nodules, and in cases of pleural effusion.

Diagnostic accuracy of transabdominal high-resolution US for staging gallbladder cancer and differential diagnosis of neoplastic polyps compared with EUS.

Science.gov (United States)

Lee, Jeong Sub; Kim, Jung Hoon; Kim, Yong Jae; Ryu, Ji Kon; Kim, Yong-Tae; Lee, Jae Young; Han, Joon Koo

2017-07-01

To compare the diagnostic accuracy of transabdominal high-resolution ultrasound (HRUS) for staging gallbladder cancer and differential diagnosis of neoplastic polyps compared with endoscopic ultrasound (EUS) and pathology. Among 125 patients who underwent both HRUS and EUS, we included 29 pathologically proven cancers (T1 = 7, T2 = 19, T3 = 3) including 15 polypoid cancers and 50 surgically proven polyps (neoplastic = 30, non-neoplastic = 20). We reviewed formal reports and assessed the accuracy of HRUS and EUS for diagnosing cancer as well as the differential diagnosis of neoplastic polyps. Statistical analyses were performed using chi-square tests. The sensitivity, specificity, PPV, and NPV for gallbladder cancer were 82.7 %, 44.4 %, 82.7 %, and 44 % using HRUS and 86.2 %, 22.2 %, 78.1 %, and 33.3 % using EUS. HRUS and EUS correctly diagnosed the stage in 13 and 12 patients. The sensitivity, specificity, PPV, and NPV for neoplastic polyps were 80 %, 80 %, 86 %, and 73 % using HRUS and 73 %, 85 %, 88 %, and 69 % using EUS. Single polyps (8/20 vs. 21/30), larger (1.0 ± 0.28 cm vs. 1.9 ± 0.85 cm) polyps, and older age (52.5 ± 13.2 vs. 66.1 ± 10.3 years) were common in neoplastic polyps (p diagnostic accuracy for GB cancer compared with EUS. • HRUS and EUS showed similar diagnostic accuracy for differentiating neoplastic polyps. • Single, larger polyps and older age were common in neoplastic polyps. • HRUS is less invasive compared with EUS.

Precise placement of lag screws in operative treatment of trochanteric femoral fractures with a new guide system.

Science.gov (United States)

Poyanli, Oguz S; Soylemez, Salih; Ozkut, Afsar T; Uygur, Esat; Kemah, Bahattin; Unal, Omer K

2015-11-01

We assessed the accuracy of a new guide system that we developed to place lag screws in the proper position with the minimum number of attempts for operative treatment of trochanteric femoral fractures. A total of 55 consecutive trochanteric femoral fractures were treated with a cephalomedullary nail. The first 27 consecutive patients were treated with the standard operation (group A), while the new guide system was used in the last 28 consecutive patients (group B). The numbers of attempts to place K wires and the duration of surgery were noted. Accuracy of lag screw placement was evaluated by measuring the angle of deviation from the central axis of the femoral head. Deviation values ranged from -11̊ to +15̊ for the 27 cases in group A, with a median absolute deviation of 8̊±6̊. That in the 28 cases after the introduction of the new guide system (group B) ranged from -5̊ to +6̊, with a median absolute deviation of 0.5̊±3̊ (Pfractures. The present study indicated that this new guide system and nail facilitate accurate placement of lag screws in the appropriate position with the minimum number of attempts. Copyright © 2015 Elsevier Ltd. All rights reserved.

Consequences of fiducial marker error on three-dimensional computer animation of the temporomandibular joint

Science.gov (United States)

Leader, J. Ken, III; Boston, J. Robert; Rudy, Thomas E.; Greco, Carol M.; Zaki, Hussein S.

2001-05-01

Jaw motion has been used to diagnose jaw pain patients, and we have developed a 3D computer animation technique to study jaw motion. A customized dental clutch was worn during motion, and its consistent and rigid placement was a concern. The experimental protocol involved mandibular movements (vertical opening) and MR imaging. The clutch contained three motion markers used to collect kinematic data and four MR markers used as fiducial markers in the MR images. Fiducial marker misplacement was mimicked by analytically perturbing the position of the MR markers +/- 2, +/- 4, and +/- 6 degrees in the three anatomical planes. The percent difference between the original and perturbed MR marker position was calculated for kinematic parameters. The maximum difference across all perturbations for axial rotation, coronal rotation, sagittal rotation, axial translation, coronal translation, and sagittal translation were 176.85%, 191.84%, 0.64%, 9.76%, 80.75%, and 8.30%, respectively, for perturbing all MR markers, and 86.47%, 93.44%, 0.23%, 7.08%, 42.64%, and 13.64%, respectively, for perturbing one MR marker. The parameters representing movement in the sagittal plane, the dominant plane in vertical opening, were determined to be reasonably robust, while secondary movements in the axial and coronal planes were not considered robust.

Endoscopic ultrasound-guided radiofrequency ablation of the pancreas

DEFF Research Database (Denmark)

Silviu, Ungureanu Bogdan; Daniel, Pirici; Claudiu, Mărgăritescu

2015-01-01

ultrasound (EUS)-guided radiofrequency ablation (RFA) probe through a 19G needle in order to achieve a desirable necrosis area in the pancreas. Radiofrequency ablation of the head of the pancreas was performed on 10 Yorkshire pigs with a weight between 25 kg and 35 kg and a length of 40-70 cm. Using an EUS...... analysis revealed increased values of amylase, alkaline phosphatase, and gamma-glutamyl transpeptidase on the 3rd day but a decrease on the 5th day. After necropsy and isolation of the pancreas, the ablated area was easily found, describing a solid necrosis. The pathological examination revealed...

A Fiducial Approach to Extremes and Multiple Comparisons

Science.gov (United States)

Wandler, Damian V.

2010-01-01

Generalized fiducial inference is a powerful tool for many difficult problems. Based on an extension of R. A. Fisher's work, we used generalized fiducial inference for two extreme value problems and a multiple comparison procedure. The first extreme value problem is dealing with the generalized Pareto distribution. The generalized Pareto…

Initial Experience with Computed Tomography and Fluoroscopically Guided Placement of Push-Type Gastrostomy Tubes Using a Rupture-Free Balloon Catheter

International Nuclear Information System (INIS)

Fujita, Takeshi; Tanabe, Masahiro; Yamatogi, Shigenari; Shimizu, Kensaku; Matsunaga, Naofumi

2011-01-01

The purpose of this study was to evaluate the safety and feasibility of percutaneous radiologic gastrostomy placement of push-type gastrostomy tubes using a rupture-free balloon (RFB) catheter under computed tomography (CT) and fluoroscopic guidance. A total of 35 patients (23 men and 12 women; age range 57–93 years [mean 71.7]) underwent percutaneous CT and fluoroscopically guided gastrostomy placement of a push-type gastrostomy tube using an RFB catheter between April 2005 and July 2008. Technical success, procedure duration, and complications were analyzed. Percutaneous radiologic gastrostomy placement was considered technically successful in all patients. The median procedure time was 39 ± 13 (SD) min (range 24–78). The average follow-up time interval was 103 days (range 7–812). No major complications related to the procedure were encountered. No tubes failed because of blockage, and neither tube dislodgement nor intraperitoneal leakage occurred during the follow-up period. The investigators conclude that percutaneous CT and fluoroscopically guided gastrostomy placement with push-type tubes using an RFB catheter is a safe and effective means of gastric feeding when performed by radiologists.

Usefulness of {sup 18}F-FDG PET, combined FDG-PET/CT and EUS in diagnosing primary pancreatic carcinoma: A meta-analysis

Energy Technology Data Exchange (ETDEWEB)

Tang Shuang [Department of Nuclear Medicine, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127 (China); Huang Gang, E-mail: huang2802@163.com [Department of Nuclear Medicine, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127 (China); Liu Jianjun [Department of Nuclear Medicine, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127 (China); Liu Tao [Department of Orthopedics, Soochow University, Suzhou (China); Treven, Lyndal [Faculty of Public Health, University of Sydney, Sydney (Australia); Song Saoli; Zhang Chenpeng; Pan Lingling [Department of Nuclear Medicine, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127 (China); Zhang Ting [Department of Anesthesiology, Renji Hospital, Shanghai (China)

2011-04-15

The aim was to evaluate the diagnostic value of {sup 18}F-fluorodeoxyglucose-positron emission tomography ({sup 18}F-FDG PET), combined {sup 18}F-fluorodeoxyglucose-positron emission tomography/computed tomography ({sup 18}F-FDG PET/CT) and endoscopic ultrasonography (EUS) in diagnosing patients with pancreatic carcinoma. MEDLINE, EMBASE, Cochrane library and some other databases, from January 1966 to April 2009, were searched for initial studies. All the studies published in English or Chinese relating to the diagnostic value of {sup 18}F-FDG PET, PET/CT and EUS for patients with pancreatic cancer were collected. Methodological quality was assessed. The statistic software called 'Meta-Disc 1.4' was used for data analysis. Results: 51 studies were included in this meta-analysis. The pooled sensitivity estimate for combined PET/CT (90.1%) was significantly higher than PET (88.4%) and EUS (81.2%). The pooled specificity estimate for EUS (93.2%) was significantly higher than PET (83.1%) and PET/CT (80.1%). The pooled DOR estimate for EUS (49.774) was significantly higher than PET (32.778) and PET/CT (27.105). SROC curves for PET/CT and EUS showed a little better diagnostic accuracy than PET alone. For PET alone, when interpreted the results with knowledge of other imaging tests, its sensitivity (89.4%) and specificity (80.1%) were closer to PET/CT. For EUS, its diagnostic value decreased in differentiating pancreatic cancer for patients with chronic pancreatitis. In conclusion, PET/CT was a high sensitive and EUS was a high specific modality in diagnosing patients with pancreatic cancer. PET/CT and EUS could play different roles during different conditions in diagnosing pancreatic carcinoma.

Endoscopic ultrasound-guided fine-needle aspiration cytology in the evaluation of suspected tuberculosis in patients with isolated mediastinal lymphadenopathy

DEFF Research Database (Denmark)

Puri, R.; Vilmann, P.; Sud, R.

2010-01-01

Patients with suspected tuberculosis without pulmonary lesions and with mediastinal lymphadenopathy often pose a diagnostic challenge. Endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) cytology is an established modality to evaluate mediastinal and abdominal lesions. The aim...... of the present study was to evaluate the role of EUS-FNA in isolated mediastinal lymphadenopathy in patients suspected of having tuberculosis....

Clinical impact of endoscopic ultrasound-guided fine needle aspiration biopsy in patients with upper gastrointestinal tract malignancies. A prospective study

DEFF Research Database (Denmark)

Mortensen, M B; Pless, T; Durup, J

2001-01-01

BACKGROUND AND STUDY AIMS: Several studies have evaluated the accuracy of endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) in the upper gastrointestinal tract, but so far no studies have specifically evaluated the clinical impact of EUS-FNAB in upper gastrointestinal tract......% in esophageal, gastric, and pancreatic cancer, respectively. The staging-related clinical impact was similar for all three types of cancer (11-12.5%), whereas the diagnosis-related impact was highest in pancreatic cancer patients (86%). EUS-FNAB was inadequate in 13% and gave false-negative results in 5......%. The overall sensitivity, specificity and accuracy for EUS-FNAB were 80%, 78% and 80%, respectively. No complications related to the biopsy procedure were seen. CONCLUSIONS: If EUS-FNAB was performed only in cases where a positive malignant result would change patient management, then approximately one out...

Infectious peritonitis after endoscopic ultrasound-guided biliary drainage in a patient with ascites

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Nozomi Okuno

2018-04-01

Full Text Available Summary of Event: Bacterial, mycotic peritonitis and Candida fungemia developed in a patient with moderate ascites who had undergone endoscopic ultrasound-guided biliary drainage (EUS-BD. Antibiotics and antifungal agent were administered and ascites drainage was performed. Although the infection improved, the patient’s general condition gradually deteriorated due to aggravation of the primary cancer and he died.Teaching Point: This is the first report to describe infectious peritonitis after EUS-BD. Ascites carries the potential risk of severe complications. As such, in patients with ascites, endoscopic retrograde cholangiopancreatography (ERCP is typically preferred over EUS-BD or percutaneous drainage to prevent bile leakage. However, ERCP may not be possible in some patients with tumor invasion of the duodenum or with surgically altered anatomy. Thus, in patients with ascites who require EUS-BD, we recommend inserting the drainage tube percutaneously and draining the ascites before and after the intervention in order to prevent severe infection.

Utility and Safety of Endoscopic Ultrasound With Bronchoscope-Guided Fine-Needle Aspiration in Mediastinal Lymph Node Sampling: Systematic Review and Meta-Analysis.

Science.gov (United States)

Dhooria, Sahajal; Aggarwal, Ashutosh N; Gupta, Dheeraj; Behera, Digambar; Agarwal, Ritesh

2015-07-01

The use of endoscopic ultrasound with bronchoscope-guided fine-needle aspiration (EUS-B-FNA) has been described in the evaluation of mediastinal lymphadenopathy. Herein, we conduct a meta-analysis to estimate the overall diagnostic yield and safety of EUS-B-FNA combined with endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), in the diagnosis of mediastinal lymphadenopathy. The PubMed and EmBase databases were searched for studies reporting the outcomes of EUS-B-FNA in diagnosis of mediastinal lymphadenopathy. The study quality was assessed using the QualSyst tool. The yield of EBUS-TBNA alone and the combined procedure (EBUS-TBNA and EUS-B-FNA) were analyzed by calculating the sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio for each study, and pooling the study results using a random effects model. Heterogeneity and publication bias were assessed for individual outcomes. The additional diagnostic gain of EUS-B-FNA over EBUS-TBNA was calculated using proportion meta-analysis. Our search yielded 10 studies (1,080 subjects with mediastinal lymphadenopathy). The sensitivity of the combined procedure was significantly higher than EBUS-TBNA alone (91% vs 80%, P = .004), in staging of lung cancer (4 studies, 465 subjects). The additional diagnostic gain of EUS-B-FNA over EBUS-TBNA was 7.6% in the diagnosis of mediastinal adenopathy. No serious complication of EUS-B-FNA procedure was reported. Clinical and statistical heterogeneity was present without any evidence of publication bias. Combining EBUS-TBNA and EUS-B-FNA is an effective and safe method, superior to EBUS-TBNA alone, in the diagnosis of mediastinal lymphadenopathy. Good quality randomized controlled trials are required to confirm the results of this systematic review. Copyright © 2015 by Daedalus Enterprises.

Sucrose acetate isobutyrate-based nanogels as liquid fiducial tissue markers with potential use in image guided radiotherapy

DEFF Research Database (Denmark)

Bruun, Linda Maria; Schaarup-Jensen, Henrik; Jølck, Rasmus Irming

The poster presents the development of a liquid fiducial tissue marker based on sucrose acetate isobutyrate (SAIB) and uniform, coated gold nanoparticles (AuNPs). The PNIPAM-coated AuNP-SAIB gel provided high CT contrast and high in vivo stability and was assessed to be a suitable tissue marker f...

Practice guidelines for endoscopic ultrasound-guided celiac plexus neurolysis

DEFF Research Database (Denmark)

Wyse, Jonathan M; Battat, Robert; Sun, Siyu

2017-01-01

OBJECTIVES: The objective of guideline was to provide clear and relevant consensus statements to form a practical guideline for clinicians on the indications, optimal technique, safety and efficacy of endoscopic ultrasound guided celiac plexus neurolysis (EUS-CPN). METHODS: Six important clinical...

Practice guidelines for endoscopic ultrasound-guided celiac plexus neurolysis

NARCIS (Netherlands)

Wyse, J.M. (Jonathan M.); Battat, R. (Robert); Sun, S. (Siyu); A. Saftoiu (Adrian); Siddiqui, A.A. (Ali A.); Leong, A.T. (Ang Tiing); Arias, B.L.A. (Brenda Lucia Arturo); Fabbri, C. (Carlo); Adler, D.G. (Douglas G.); Santo, E. (Erwin); Kalaitzakis, E. (Evangelos); Artifon, E. (Everson); Mishra, G. (Girish); Okasha, H.H. (Hussein Hassan); J.-W. Poley (Jan-Werner); Guo, J. (Jintao); Vila, J.J. (Juan J.); Lee, L.S. (Linda S.); Sharma, M. (Malay); Bhutani, M.S. (Manoop S.); M. Giovannini (Marcello); Kitano, M. (Masayuki); Eloubeidi, M.A. (Mohamad Ali); Khashab, M.A. (Mouen A.); Nguyen, N.Q. (Nam Q.); Saxena, P. (Payal); Vilmann, P. (Peter); Fusaroli, P. (Pietro); Garg, P.K. (Pramod Kumar); Ho, S. (Sammy); Mukai, S. (Shuntaro); Carrara, S. (Silvia); Sridhar, S. (Subbaramiah); S. Lakhtakia (S.); Rana, S.S. (Surinder S.); Dhir, V. (Vinay); Sahai, A.V. (Anand V.)

2017-01-01

textabstractObjectives: The objective of guideline was to provide clear and relevant consensus statements to form a practical guideline for clinicians on the indications, optimal technique, safety and efficacy of endoscopic ultrasound guided celiac plexus neurolysis (EUS-CPN). Methods: Six important

On a laser beam fiducial line application for metrological purposes

International Nuclear Information System (INIS)

Batusov, V.; Budagov, J.; Lyablin, M.; Rusakovich, N.; Sisakyan, A.; Topilin, N.; Khubua, J.; Lasseur, C.

2008-01-01

The possibility of a collimated one-mode laser beam used as a fiducial line is considered. The technology of an 'extended' laser beam formation and application for a much extended fiducial line is proposed

Image-guided left ventricular lead placement in cardiac resynchronization therapy for patients with heart failure: a meta-analysis.

Science.gov (United States)

Jin, Yan; Zhang, Qi; Mao, Jia-Liang; He, Ben

2015-05-10

Heart failure (HF) is a debilitating condition that affects millions of people worldwide. One means of treating HF is cardiac resynchronization therapy (CRT). Recently, several studies have examined the use of echocardiography (ECHO) in the optimization of left ventricular (LV) lead placement to increase the response to CRT. The objective of this study was to synthesize the available data on the comparative efficacy of image-guided and standard CRT. We searched the PubMed, Cochrane, Embase, and ISI Web of Knowledge databases through April 2014 with the following combinations of search terms: left ventricular lead placement, cardiac resynchronization therapy, image-guided, and echocardiography-guided. Studies meeting all of the inclusion criteria and none of the exclusion criteria were eligible for inclusion. The primary outcome measures were CRT response rate, change in LV ejection fraction (LVEF), and change in LV end systolic volume (LVESV). Secondary outcomes included the rates of all-cause mortality and HF-related hospitalization. Our search identified 103 articles, 3 of which were included in the analysis. In total, 270 patients were randomized to the image-guided CRT and 241, to the standard CRT. The pooled estimates showed a significant benefit for image-guided CRT (CRT response: OR, 2.098, 95 % CI, 1.432-3.072; LVEF: difference in means, 3.457, 95 % CI, 1.910-5.005; LVESV: difference in means, -20.36, 95 % CI, -27.819 - -12.902). Image-guided CRT produced significantly better clinical outcomes than the standard CRT. Additional trials are warranted to validate the use of imaging in the prospective optimization of CRT.

Endoscopic Ultrasound-Guided Biliary Drainage Using Self-Expandable Metal Stent for Malignant Biliary Obstruction

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Lei Lu

2017-01-01

Full Text Available Purpose. Endoscopic ultrasound-guided biliary drainage (EUS-BD has been increasingly reported worldwide. However, studies concerning EUS-BD from Mainland China are sporadic. This study aims to investigate the feasibility, efficacy, and safety of EUS-BD using SEMS in a single center from Mainland China. Methods. Between November 2011 and August 2015, 24 patients underwent EUS-BD using a standardized algorithm. Results. Three patients underwent rendezvous technique (RV, 4 underwent hepaticogastrostomy (HGS, and 17 underwent choledochoduodenostomy (CDS. The technical and clinical success rates were 95.8% (23/24 and 100% (23/23, respectively. Mean procedure time for the CDS group (35.9 ± 5.0 min or HGS group (39.3 ± 5.0 min was significantly shorter than that for the RV group (64.7 ± 9.1 min (P<0.05. Complications (13% included (1 cholangitis and (2 postprocedure hemorrhage. During the follow-up periods (mean 6.4 months, 22 (91.7% patients died of tumor progression with mean stent patency of 5.8 ± 2.2 months. Stent occlusion occurred in 2 (8.7% patients. Conclusion. EUS-BD using SEMS is a feasible, effective, and safe alternative for biliary decompression after failed ERCP. EUS-RV may not be the first-line choice for EUS-BD in a medium volume center. Further evaluation and experience of this method are needed.

A novel "hitch-and-ride" deep biliary cannulation method during rendezvous endoscopic ultrasound-guided ERCP technique.

Science.gov (United States)

Nakai, Yousuke; Isayama, Hiroyuki; Matsubara, Saburo; Kogure, Hirofumi; Mizuno, Suguru; Hamada, Tsuyoshi; Takahara, Naminatsu; Nakamura, Tomoka; Sato, Tatsuya; Takeda, Tsuyoshi; Hakuta, Ryunosuke; Ishigaki, Kazunaga; Saito, Kei; Tada, Minoru; Koike, Kazuhiko

2017-10-01

Background and study aim Endoscopic ultrasound-guided rendezvous (EUS-RV) is increasingly reported as a treatment option after failed endoscopic retrograde cholangiopancreatography. We developed a novel "hitch-and-ride" catheter for biliary cannulation to reduce the risk of guidewire loss during EUS-RV. Patients and methods We retrospectively evaluated safety and technical success of EUS-RV between June 2011 and May 2016. Biliary cannulation during EUS-RV using three methods - over-the-wire, along-the-wire, and hitch-and-ride - were compared. Results A total of 30 EUS-RVs were attempted and the technical success rate was 93.3 %, with two failures (one bile duct puncture and one guidewire insertion). After 28 cases of successful guidewire passage, cannulation was attempted by the over-the-wire (n = 13), along-the-wire (n = 4) or hitch-and-ride (n = 11) method. Only the hitch-and-ride method achieved biliary cannulation without guidewire loss or conversion to the other methods. Time to cannulation was shorter with the hitch-and-ride method (4 minutes) than with over-the-wire and along-the-wire methods (9 and 13 minutes, respectively). The adverse event rate of EUS-RV was 23.3 %. Conclusion A novel hitch-and-ride catheter was feasible for biliary cannulation after EUS-RV. © Georg Thieme Verlag KG Stuttgart · New York.

Microscopic Gold Particle-Based Fiducial Markers for Proton Therapy of Prostate Cancer

International Nuclear Information System (INIS)

Lim, Young Kyung; Kwak, Jungwon; Kim, Dong Wook; Shin, Dongho; Yoon, Myonggeun; Park, Soah; Kim, Jin Sung; Ahn, Sung Hwan; Shin, Jungwook; Lee, Se Byeong; Park, Sung Yong; Pyo, Hong Ryeol; Kim, Dae Yong M.D.; Cho, Kwan Ho

2009-01-01

Purpose: We examined the feasibility of using fiducial markers composed of microscopic gold particles and human-compatible polymers as a means to overcome current problems with conventional macroscopic gold fiducial markers, such as dose reduction and artifact generation, in proton therapy for prostate cancer. Methods and Materials: We examined two types of gold particle fiducial marker interactions: that with diagnostic X-rays and with a therapeutic proton beam. That is, we qualitatively and quantitatively compared the radiographic visibility of conventional gold and gold particle fiducial markers and the CT artifacts and dose reduction associated with their use. Results: The gold particle fiducials could be easily distinguished from high-density structures, such as the pelvic bone, in diagnostic X-rays but were nearly transparent to a proton beam. The proton dose distribution was distorted <5% by the gold particle fiducials with a 4.9% normalized gold density; this was the case even in the worst configuration (i.e., parallel alignment with a single-direction proton beam). In addition, CT artifacts were dramatically reduced for the gold particle mixture. Conclusion: Mixtures of microscopic gold particles and human-compatible polymers have excellent potential as fiducial markers for proton therapy for prostate cancer. These include good radiographic visibility, low distortion of the depth-dose distribution, and few CT artifacts.

Comparison of respiratory surrogates for gated lung radiotherapy without internal fiducials

International Nuclear Information System (INIS)

Korreman, S.; Mostafavi, H.; Le, Q.T.; Boyer, A.

2006-01-01

An investigation was carried out to compare the ability of two respiratory surrogates to mimic actual lung tumor motion during audio coaching. The investigation employed video clips acquired after patients had had fiducial markers implanted in lung tumors to be used for image-guided stereoscopic radiotherapy. The positions of the markers in the clips were measured within the video frames and used as the standard for tumor volume motion. An external marker was tracked optically during the fluoroscopic acquisitions. An image correlation technique was developed to compute a gating signal from the fluoroscopic images. The correlation gating trace was similar to the optical gating trace in the phase regions of the respiratory cycle used for gating. A cross correlation analysis and comparison of the external optical marker gating with internal fluoroscopic gating was performed. The fluoroscopic image correlation surrogate was found to be superior to the external optical surrogate in the AP-views in four out of six cases. In one of the remaining two cases, the two surrogates performed comparably, while in the last case, the external fiducial trace performed best. It was concluded that fluoroscopic gating based on correlation of native image features in the fluoroscopic images will be adequate for respiratory gating

Comparison of respiratory surrogates for gated lung radiotherapy without internal fiducials

Energy Technology Data Exchange (ETDEWEB)

Korreman, S. [Rigshospitalet, Copenhagen (Denmark). Dept. of Radiation Oncology; Mostafavi, H. [Varian Medical Systems, Mountain View, CA (United States). Gintzon Technology Center; Le, Q.T.; Boyer, A. [Stanford Univ. School of Medicine, CA (United States). Dept. of Radiation Oncology

2006-09-15

An investigation was carried out to compare the ability of two respiratory surrogates to mimic actual lung tumor motion during audio coaching. The investigation employed video clips acquired after patients had had fiducial markers implanted in lung tumors to be used for image-guided stereoscopic radiotherapy. The positions of the markers in the clips were measured within the video frames and used as the standard for tumor volume motion. An external marker was tracked optically during the fluoroscopic acquisitions. An image correlation technique was developed to compute a gating signal from the fluoroscopic images. The correlation gating trace was similar to the optical gating trace in the phase regions of the respiratory cycle used for gating. A cross correlation analysis and comparison of the external optical marker gating with internal fluoroscopic gating was performed. The fluoroscopic image correlation surrogate was found to be superior to the external optical surrogate in the AP-views in four out of six cases. In one of the remaining two cases, the two surrogates performed comparably, while in the last case, the external fiducial trace performed best. It was concluded that fluoroscopic gating based on correlation of native image features in the fluoroscopic images will be adequate for respiratory gating.

CT fluoroscopy-guided preoperative short hook wire placement for small pulmonary lesions: evaluation of safety and identification of risk factors for pneumothorax.

Science.gov (United States)

Iguchi, Toshihiro; Hiraki, Takao; Gobara, Hideo; Fujiwara, Hiroyasu; Matsui, Yusuke; Miyoshi, Shinichiro; Kanazawa, Susumu

2016-01-01

To retrospectively evaluate the safety of computed tomography (CT) fluoroscopy-guided short hook wire placement for video-assisted thoracoscopic surgery and the risk factors for pneumothorax associated with this procedure. We analyzed 267 short hook wire placements for 267 pulmonary lesions (mean diameter, 9.9 mm). Multiple variables related to the patients, lesions, and procedures were assessed to determine the risk factors for pneumothorax. Complications (219 grade 1 and 4 grade 2 adverse events) occurred in 196 procedures. No grade 3 or above adverse events were observed. Univariate analysis revealed increased vital capacity (odds ratio [OR], 1.518; P = 0.021), lower lobe lesion (OR, 2.343; P =0.001), solid lesion (OR, 1.845; P = 0.014), prone positioning (OR, 1.793; P = 0.021), transfissural approach (OR, 11.941; P = 0.017), and longer procedure time (OR, 1.036; P = 0.038) were significant predictors of pneumothorax. Multivariate analysis revealed only the transfissural approach (OR, 12.171; P = 0.018) and a longer procedure time (OR, 1.048; P = 0.012) as significant independent predictors. Complications related to CT fluoroscopy-guided preoperative short hook wire placement often occurred, but all complications were minor. A transfissural approach and longer procedure time were significant independent predictors of pneumothorax. Complications related to CT fluoroscopy-guided preoperative short hook wire placement often occur. Complications are usually minor and asymptomatic. A transfissural approach and longer procedure time are significant independent predictors of pneumothorax.

Clinical utility of an endoscopic ultrasound-guided rendezvous technique via various approach routes.

Science.gov (United States)

Kawakubo, Kazumichi; Isayama, Hiroyuki; Sasahira, Naoki; Nakai, Yousuke; Kogure, Hirofumi; Hamada, Tsuyoshi; Miyabayashi, Koji; Mizuno, Suguru; Sasaki, Takashi; Ito, Yukiko; Yamamoto, Natsuyo; Hirano, Kenji; Tada, Minoru; Koike, Kazuhiko

2013-09-01

The endoscopic ultrasound-guided rendezvous techniques (EUS-rendezvous) provide reliable biliary access after failed endoscopic retrograde cholangiopancreatography (ERCP) cannulation. We evaluated the clinical utility of an EUS-rendezvous technique using various approach routes. Patients undergoing EUS-rendezvous for biliary access after failed bile duct cannulation in ERCP were included. EUS-rendezvous was performed via three approach routes depending on the patient's condition: transgastric, transduodenal in a short endoscopic position, or transduodenal in a long endoscopic position. The main outcomes were the technical success rates. Secondary outcomes were procedure time and complications. Fourteen patients (median age, 77 years) underwent EUS-rendezvous for biliary access resulting from failed biliary cannulation. The reasons for biliary drainage were malignant biliary obstruction in five patients and choledocholithiasis in nine. Transgastric, transduodenal in a short position, and transduodenal in a long position EUS-rendezvous was performed in five, five, and four patients, respectively. Bile duct puncture occurred in the left intrahepatic duct in four patients, right hepatic duct in one, middle common bile duct in four, and lower common bile duct in five. The technical success rate was 100 %. In four patients, the approach route was modified from transduodenal in a short position to transduodenal in a long position or transgastric route. The median procedure time was 81 min. One case each of biliary peritonitis and pancreatitis occurred and were managed conservatively. EUS-rendezvous provided safe and reliable transpapillary bile duct access after failed ERCP cannulation. The selection of the appropriate approach routes, depending on patient condition, is critical.

Diagnostic performance of EUS in predicting advanced cancer among patients with Barrett's esophagus and high-grade dysplasia/early adenocarcinoma: systematic review and meta-analysis.

Science.gov (United States)

Qumseya, Bashar J; Brown, Jessica; Abraham, Merna; White, Donna; Wolfsen, Herbert; Gupta, Neil; Vennalaganti, Prashanth; Sharma, Prateek; Wallace, Michael B

2015-04-01

The role of EUS among patients with Barrett's esophagus (BE) with high-grade dysplasia (HGD) or suspected mucosal carcinoma is controversial. To define the role of EUS in detecting advanced disease among patients with BE. Systematic review and meta-analysis. MEDLINE, Embase, Web of Science, and Cochrane Central databases. Patients with BE and HGD or esophageal adenocarcinoma (EAC) who were referred for endoscopic evaluation and underwent EUS. EUS. Pooled proportion of patients with advanced EAC identified by EUS among patients with BE who are referred for HGD or EAC (with or without visible lesions). Forest plots were used to contrast effect sizes in each of the studies and random effect models when tests of heterogeneity were significant (I(2) > 50% or P statistic). Of 1278 articles, 47 were reviewed in full text, and 11 articles met the inclusion criteria, including a total of 656 patients. Based on a random-effects model, the proportion of patients with advanced disease detected on EUS was 14% (95% confidence interval, 8%-22%; P advanced disease on EUS in the absence of nodules was 4% (95% confidence interval, 2%-6%, P < .0001). Significant heterogeneity among studies. EUS will result in a change in the therapeutic approach among in a significant minority of patients with BE who are referred for HGD or EAC. Copyright © 2015. Published by Elsevier Inc.

Neutron Scattering from Heisenberg Ferromagnets EuO and EuS

DEFF Research Database (Denmark)

Als-Nielsen, Jens Aage; Dietrich, O. W.; Passell, L.

1976-01-01

Neutron scattering has been used to study the magnetic ordering process in the isotropic exchange coupled ferromagnets EuO and EuS. Quantities investigated include the critical coefficients B and F+ and the critical exponents β, ν, and γ describing respectively the temperature dependence...

Endoscopic Ultrasound-guided Rendezvous Technique after Failed Endoscopic Retrograde Cholangiopancreatography: Which Approach Route Is the Best?

Science.gov (United States)

Okuno, Nozomi; Hara, Kazuo; Mizuno, Nobumasa; Hijioka, Susumu; Tajika, Masahiro; Tanaka, Tsutomu; Ishihara, Makoto; Hirayama, Yutaka; Onishi, Sachiyo; Niwa, Yasumasa; Yamao, Kenji

2017-12-01

Objective The endoscopic ultrasound-guided rendezvous technique (EUS-RV) is a salvage method for failed selective biliary cannulation. Three puncture routes have been reported, with many comparisons between the intra-hepatic and extra-hepatic biliary ducts. We used the trans-esophagus (TE) and trans-jejunum (TJ) routes. In the present study, the utility of EUS-RV for biliary access was evaluated, focusing on the approach routes. Methods and Patients In 39 patients, 42 puncture routes were evaluated in detail. EUS-RV was performed between January 2010 and December 2014. The patients were prospectively enrolled, and their clinical data were retrospectively collected. Results The patients' median age was 71 (range 29-84) years. The indications for endoscopic retrograde cholangiopancreatography (ERCP) were malignant biliary obstruction in 24 patients and benign biliary disease in 15. The technical success rate was 78.6% (33/42) and was similar among approach routes (p=0.377). The overall complication rate was 16.7% (7/42) and was similar among approach routes (p=0.489). However, mediastinal emphysema occurred in 2 TE route EUS-RV patients. No EUS-RV-related deaths occurred. Conclusion EUS-RV proved reliable after failed ERCP. The selection of the appropriate route based on the patient's condition is crucial.

The role of routine preoperative EUS when performed after contrast enhanced CT in the diagnostic work-up in patients suspected of pancreatic or periampullary cancer.

Science.gov (United States)

Cieslak, Kasia P; van Santvoort, Hjalmar C; Vleggaar, Frank P; van Leeuwen, Maarten S; ten Kate, Fibo J; Besselink, Marc G; Molenaar, I Quintus

2014-01-01

In patients suspected of pancreatic or periampullary cancer, abdominal contrast-enhanced computed tomography (CT) is the standard diagnostic modality. A supplementary endoscopic ultrasonography (EUS) is often performed, although there is only limited evidence of its additional diagnostic value. The aim of the study is to evaluate the additional diagnostic value of EUS over CT in deciding on exploratory laparotomy in patients suspected of pancreatic or periampullary cancer. We retrospectively analyzed 86 consecutive patients who routinely underwent CT and EUS before exploratory laparotomy with or without pancreatoduodenectomy for suspected pancreatic or periampullary carcinoma between 2007 and 2010. Primary outcomes were visibility of a mass, resectability on CT/EUS and resection with curative intent. A mass was visible on CT in 72/86 (84%) patients. In these 72 patients, EUS demonstrated a mass in 64/72 (89%) patients. Resectability was accurately predicted by CT in 65/72 (90%) and by EUS in 58/72 (81%) patients. In 14/86 (16%) patients no mass was seen on CT. EUS showed a mass in 12/14 (86%) of these patients. A malignant lesion was histological proven in 11/12 (92%) of these patients. Overall, resectability was accurately predicted by CT and EUS in 90% (77/86) and 84% (72/86), respectively. In patients with a visible mass on CT, suspected for pancreatic or periampullary cancer, EUS has no additional diagnostic value, does not influence the decision to perform laparotomy and should therefore not be performed routinely. In patients without a visible mass on CT, EUS is useful to confirm the presence of a tumor. Copyright © 2014 IAP and EPC. Published by Elsevier B.V. All rights reserved.

Eosinophilic esophageal myositis diagnosed by endoscopic ultrasound-guided fine-needle aspiration biopsy: a case report.

Science.gov (United States)

Igarashi, Ryo; Irisawa, Atsushi; Shibukawa, Goro; Yamabe, Akane; Fujisawa, Mariko; Sato, Ai; Maki, Takumi; Arakawa, Noriyuki; Yoshida, Yoshitsugu; Yamamoto, Shogo; Ikeda, Tsunehiko

2016-10-01

Eosinophilic esophagitis (EoE) is diagnosed by microscopic findings of eosinophilic infiltration into the squamous epithelium. In contrast, another disease concept termed "eosinophilic esophageal myositis (EoEM)" has been proposed, whereby there is eosinophilic infiltration into the muscularis propria instead. A 60-year-old man was referred to our hospital for chest pain, dysphagia, and several episodes of esophageal food impaction. Although EoE was suspected based on clinical features, biopsy specimens showed no mucosal eosinophilic infiltration. Endoscopic ultrasound (EUS) showed thickening of the muscularis propria layer and subsequent EUS-guided fine-needle aspiration biopsy (EUS-FNA) revealed eosinophilic infiltration into the muscularis propria. Although the patient's symptoms gradually improved after steroid administration, complete remission was not achieved after 1 year of treatment. This case may reflect a disorder distinct from typical EoE based on eosinophilic infiltration of the muscularis propria but not the squamous epithelium, and we, therefore, diagnosed it as EoEM using the EUS-FNA findings as reference.

A fast fiducial marker tracking model for fully automatic alignment in electron tomography

KAUST Repository

Han, Renmin; Zhang, Fa; Gao, Xin

2017-01-01

Automatic alignment, especially fiducial marker-based alignment, has become increasingly important due to the high demand of subtomogram averaging and the rapid development of large-field electron microscopy. Among the alignment steps, fiducial marker tracking is a crucial one that determines the quality of the final alignment. Yet, it is still a challenging problem to track the fiducial markers accurately and effectively in a fully automatic manner.In this paper, we propose a robust and efficient scheme for fiducial marker tracking. Firstly, we theoretically prove the upper bound of the transformation deviation of aligning the positions of fiducial markers on two micrographs by affine transformation. Secondly, we design an automatic algorithm based on the Gaussian mixture model to accelerate the procedure of fiducial marker tracking. Thirdly, we propose a divide-and-conquer strategy against lens distortions to ensure the reliability of our scheme. To our knowledge, this is the first attempt that theoretically relates the projection model with the tracking model. The real-world experimental results further support our theoretical bound and demonstrate the effectiveness of our algorithm. This work facilitates the fully automatic tracking for datasets with a massive number of fiducial markers.The C/C ++ source code that implements the fast fiducial marker tracking is available at https://github.com/icthrm/gmm-marker-tracking. Markerauto 1.6 version or later (also integrated in the AuTom platform at http://ear.ict.ac.cn/) offers a complete implementation for fast alignment, in which fast fiducial marker tracking is available by the

A fast fiducial marker tracking model for fully automatic alignment in electron tomography

KAUST Repository

Han, Renmin

2017-10-20

Automatic alignment, especially fiducial marker-based alignment, has become increasingly important due to the high demand of subtomogram averaging and the rapid development of large-field electron microscopy. Among the alignment steps, fiducial marker tracking is a crucial one that determines the quality of the final alignment. Yet, it is still a challenging problem to track the fiducial markers accurately and effectively in a fully automatic manner.In this paper, we propose a robust and efficient scheme for fiducial marker tracking. Firstly, we theoretically prove the upper bound of the transformation deviation of aligning the positions of fiducial markers on two micrographs by affine transformation. Secondly, we design an automatic algorithm based on the Gaussian mixture model to accelerate the procedure of fiducial marker tracking. Thirdly, we propose a divide-and-conquer strategy against lens distortions to ensure the reliability of our scheme. To our knowledge, this is the first attempt that theoretically relates the projection model with the tracking model. The real-world experimental results further support our theoretical bound and demonstrate the effectiveness of our algorithm. This work facilitates the fully automatic tracking for datasets with a massive number of fiducial markers.The C/C ++ source code that implements the fast fiducial marker tracking is available at https://github.com/icthrm/gmm-marker-tracking. Markerauto 1.6 version or later (also integrated in the AuTom platform at http://ear.ict.ac.cn/) offers a complete implementation for fast alignment, in which fast fiducial marker tracking is available by the

Endoscopic ultrasound-guided pancreaticobiliary intervention in patients with surgically altered anatomy and inaccessible papillae: A review of current literature

Science.gov (United States)

Martin, Aaron; Kistler, Charles Andrew; Wrobel, Piotr; Yang, Juliana F.; Siddiqui, Ali A.

2016-01-01

The management of pancreaticobiliary disease in patients with surgically altered anatomy is a growing problem for gastroenterologists today. Over the years, endoscopic ultrasound (EUS) has emerged as an important diagnostic and therapeutic modality in the treatment of pancreaticobiliary disease. Patient anatomy has become increasingly complex due to advances in surgical resection of pancreaticobiliary disease and EUS has emerged as the therapy of choice when endoscopic retrograde cholangiopancreatography failed cannulation or when the papilla is inaccessible such as in gastric obstruction or duodenal obstruction. The current article gives a comprehensive review of the current literature for EUS-guided intervention of the pancreaticobiliary tract in patients with altered surgical anatomy. PMID:27386471

Optical third harmonic generation in the magnetic semiconductor EuSe

Science.gov (United States)

Lafrentz, M.; Brunne, D.; Kaminski, B.; Pavlov, V. V.; Pisarev, R. V.; Henriques, A. B.; Yakovlev, D. R.; Springholz, G.; Bauer, G.; Bayer, M.

2012-01-01

Third harmonic generation (THG) has been studied in europium selenide EuSe in the vicinity of the band gap at 2.1-2.6 eV and at higher energies up to 3.7 eV. EuSe is a magnetic semiconductor crystalizing in centrosymmetric structure of rock-salt type with the point group m3m. For this symmetry the crystallographic and magnetic-field-induced THG nonlinearities are allowed in the electric-dipole approximation. Using temperature, magnetic field, and rotational anisotropy measurements, the crystallographic and magnetic-field-induced contributions to THG were unambiguously separated. Strong resonant magnetic-field-induced THG signals were measured at energies in the range of 2.1-2.6 eV and 3.1-3.6 eV for which we assign to transitions from 4f7 to 4f65d1 bands, namely involving 5d(t2g) and 5d(eg) states.

Balanced Propofol Sedation in Patients Undergoing EUS-FNA: A Pilot Study to Assess Feasibility and Safety

Directory of Open Access Journals (Sweden)

N. Pagano

2011-01-01

Full Text Available Introduction and aims. Balanced propofol sedation (BPS administered by gastroenterologists has gained popularity in endoscopic procedures. Few studies exist about the safety of this approach during endosonography with fine needle aspiration (EUS-FNA. We assessed the safety of BPS in EUS-FNA. Materials and methods. 112 consecutive patients, referred to our unit to perform EUS-FNA, from February 2008 to December 2009, were sedated with BPS. A second gastroenterologist administered the drugs and monitorized the patient. Results. All the 112 patients (62 males, mean age 58.35 completed the examination. The mean dose of midazolam and propofol was, respectively, of 2.1 mg (range 1–4 mg and 350 mg (range 180–400. All patients received oxygen with a mean flux of 4 liter/minute (range 2–6 liters/minute. The mean recovery time after procedure was 25 minutes (range 18–45 minutes. No major complications related to sedation were registered during all procedures. The oxygen saturation of all patients never reduced to less than 85%. Blood systolic pressure during and after the procedure never reduced to less than 100 mmHg. Conclusions. In our experience BPS administered by non-anaesthesiologists provided safe and successful sedation in patients undergoing EUS-FNA.

Endoscopic ultrasound guided biopsy performed routinely in lung cancer staging spares futile thoracotomies

DEFF Research Database (Denmark)

Larsen, Soeren S; Vilmann, Peter; Krasnik, Mark

2005-01-01

BACKGROUND: Up to 45% of operations with curative intent for non-small-cell lung cancer (NSCLC) can be regarded as futile, apparently because the stage of the disease is more advanced than expected preoperatively. During the past decade several studies have evaluated the usefulness of endoscopic...... ultrasound guided fine needle aspiration biopsy (EUS-FNA) in lung cancer staging with promising results. However, no randomised trials have been performed, in which a staging strategy with EUS-FNA performed in all patients is compared with a conventional workup. METHODS: Before surgery (i.e. mediastinoscopy...

Spatially modulated magnetic structure of EuS due to the tetragonal domain structure of SrTiO3 APS

CERN Document Server

Rosenberg, Aaron J.; Kirtley, John R.; Gedik, Nuh; Moodera, Jagadeesh S.; Moler, Kathryn A.

2017-12-15

The combination of ferromagnets with topological superconductors or insulators allows for new phases of matter that support excitations such as chiral edge modes and Majorana fermions. EuS, a wide-bandgap ferromagnetic insulator with a Curie temperature around 16 K, and SrTiO3 (STO), an important substrate for engineering heterostructures, may support these phases. We present scanning superconducting quantum interference device measurements of EuS grown epitaxially on STO that reveal micron-scale variations in ferromagnetism and paramagnetism. These variations are oriented along the STO crystal axes and only change their configuration upon thermal cycling above the STO cubic-to-tetragonal structural transition temperature at 105 K, indicating that the observed magnetic features are due to coupling between EuS and the STO tetragonal structure. We speculate that the STO tetragonal distortions may strain the EuS, altering the magnetic anisotropy on a micron scale. This result demonstrates that local variation in...

Monte Carlo simulations of the dosimetric impact of radiopaque fiducial markers for proton radiotherapy of the prostate

Science.gov (United States)

Newhauser, Wayne; Fontenot, Jonas; Koch, Nicholas; Dong, Lei; Lee, Andrew; Zheng, Yuanshui; Waters, Laurie; Mohan, Radhe

2007-06-01

Many clinical studies have demonstrated that implanted radiopaque fiducial markers improve targeting accuracy in external-beam radiotherapy, but little is known about the dose perturbations these markers may cause in patients receiving proton radiotherapy. The objective of this study was to determine what types of implantable markers are visible in setup radiographs and, at the same time, perturb the therapeutic proton dose to the prostate by less than 10%. The radiographic visibility of the markers was assessed by visual inspection of lateral setup radiographs of a pelvic phantom using a kilovoltage x-ray imaging system. The fiducial-induced perturbations in the proton dose were estimated with Monte Carlo simulations. The influence of marker material, size, placement depth and orientation within the pelvis was examined. The radiographic tests confirmed that gold and stainless steel markers were clearly visible and that titanium markers were not. The Monte Carlo simulations revealed that titanium and stainless steel markers minimally perturbed the proton beam, but gold markers cast unacceptably large dose shadows. A 0.9 mm diameter, 3.1 mm long cylindrical stainless steel marker provides good radiographic visibility yet perturbs the proton dose distribution in the prostate by less than 8% when using a parallel opposed lateral beam arrangement.

Assessment of a daily online implanted fiducial marker-guided prostate radiotherapy process.

Science.gov (United States)

Greer, P B; Dahl, K; Ebert, M A; White, M; Wratten, C; Ostwald, P; Pichler, P; Denham, J W

2008-10-01

The aims of this study were to investigate whether intrafraction prostate motion can affect the accuracy of online prostate positioning using implanted fiducial markers and to determine the effect of prostate rotations on the accuracy of the software-predicted set-up correction shifts. Eleven patients were treated with implanted prostate fiducial markers and online set-up corrections. Orthogonal electronic portal images were acquired to determine couch shifts before treatment. Verification images were also acquired during treatment to assess whether intrafraction motion had occurred. A limitation of the online image registration software is that it does not allow for in-plane prostate rotations (evident on lateral portal images) when aligning marker positions. The accuracy of couch shifts was assessed by repeating the registration measurements with separate software that incorporates full in-plane prostate rotations. Additional treatment time required for online positioning was also measured. For the patient group, the overall postalignment systematic prostate errors were less than 1.5 mm (1 standard deviation) in all directions (range 0.2-3.9 mm). The random prostate errors ranged from 0.8 to 3.3 mm (1 standard deviation). One patient exhibited intrafraction prostate motion, resulting in a postalignment prostate set-up error of more than 10 mm for one fraction. In 14 of 35 fractions, the postalignment prostate set-up error was greater than 5 mm in the anterior-posterior direction for this patient. Maximum prostate rotations measured from the lateral images varied from 2 degrees to 20 degrees for the patients. The differences between set-up shifts determined by the online software without in-plane rotations to align markers, and with rotations applied, was less than 1 mm (root mean square), with a maximum difference of 4.1 mm. Intrafraction prostate motion was found to reduce the effectiveness of the online set-up for one of the patients. A larger study is required

Immediate placement and provisionalization of maxillary anterior single implant with guided bone regeneration, connective tissue graft, and coronally positioned flap procedures.

Science.gov (United States)

Waki, Tomonori; Kan, Joseph Y K

2016-01-01

Immediate implant placement and provisionalization in the esthetic zone have been documented with success. The benefit of immediate implant placement and provisionalization is the preservation of papillary mucosa. However, in cases with osseous defects presenting on the facial bony plate, immediate implant placement procedures have resulted in facial gingival recession. Subepithelial connective tissue grafts for immediate implant placement and provisionalization procedures have been reported with a good esthetic outcome. Biotype conversion around implants with subepithelial connective tissue grafts have been advocated, and the resulting tissues appear to be more resistant to recession. The dimensions of peri-implant mucosa in a thick biotype were significantly greater than in a thin biotype. Connective tissue graft with coronally positioned flap procedures on natural teeth has also been documented with success. This article describes a technique combining immediate implant placement, provisionalization, guided bone regeneration (GBR), connective tissue graft, and a coronally positioned flap in order to achieve more stable peri-implant tissue in facial osseous defect situations.

Implementation of Fiducial-Based Image Registration in the Cyberknife Robotic System

International Nuclear Information System (INIS)

Saw, Cheng B.; Chen Hungcheng; Wagner, Henry

2008-01-01

Fiducial-based image registration methodology as implemented in the Cyberknife system is explored. The Cyberknife is a radiosurgery system that uses image guidance technology and computer-controlled robotics to determine target positions and adjust beam directions accordingly during the dose delivery. The image guidance system consists of 2 x-ray sources mounted on the ceiling and a detection system mounted on both sides of the treatment couch. Two orthogonal live radiographs are taken prior to and during patient treatment. Fiducial markers are identified on these radiographs and compared to a library of digital reconstructed radiographs (DRRs) using the fiducial extraction software. The fiducial extraction software initially sets an intensity threshold on the live radiographs to generate white areas on black images referred to as 'blobs.' Different threshold values are being used and blobs at the same location are assumed to originate from the same object. The number of blobs is then reduced by examining each blob against a predefined set of properties such as shape and exposure levels. The remaining blobs are further reduced by examining the location of the blobs in the inferior-superior patient axis. Those blobs that have the corresponding positions are assumed to originate from the same object. The remaining blobs are used to create fiducial configurations and are compared to the reference configuration from the computed tomography (CT) image dataset for treatment planning. The best-fit configuration is considered to have the appropriate fiducial markers. The patient position is determined based on these fiducial markers. During the treatment, the radiation beam is turned off when the Cyberknife changes nodes. This allows a time window to acquire live radiographs for the determination of the patient target position and to update the robotic manipulator to change beam orientations accordingly

Value of computed tomography for evaluating the injection site in endosonography-guided celiac plexus neurolysis

International Nuclear Information System (INIS)

Sakamoto, Hiroki; Kitano, Masayuki; Nishio, Takeshi; Takeyama, Yoshifumi; Yasuda, Chikao; Kudo, Masatoshi

2006-01-01

Endosonography-guided celiac plexus neurolysis (EUS-CPN) safely and effectively relieves pain associated with intra-abdominal malignancies when the neurolytic is accurately injected. We applied contrast medium to evaluate the ethanol injection sites in patients who received EUS-CPN due to abdominal pain caused by malignancies. We injected, under the guidance of endoscopic ultrasonography (EUS), ethanol containing 10% contrast medium into the celiac plexus of patients with intra-abdominal pain due to malignancies. Immediately after the endoscopic therapy, patients underwent computed tomography (CT) to confirm the injection site. Images of distribution of injected solutions were classified into three groups. Injected solution dispersed in unilateral and bilateral anterocrural space was defined as ''unilateral injection'' or bilateral injection'', respectively. Injected solution located out of the anterocrural space was defined as ''inappropriate injection''. Pre- and postprocedure pain was assessed using a standard analog scale. Before and 2, 4, 8, 12, and 16 weeks after the procedure, pain scores were evaluated. From April 2003 to May 2005, 13 patients were enrolled in this study. Improvement of pain score in the ''bilateral injection'' and ''unilateral injection'' groups was significantly superior to the change in the ''inappropriate injection'' group. Although EUS-CPN was effective in eight of 13 patients (61.5%), additional EUS-CPN to the ''inappropriate injection group'' increased the response rate to 84.6%. Injection of ethanol to the anterocrural space by EUS-CPN produced adequate pain relief. Immediate examination by CT for confirmation of injection sites after EUS-CPN would increase the likelihood of induction of pain relief. (author)

Combined kV and MV imaging for real-time tracking of implanted fiducial markers

International Nuclear Information System (INIS)

Wiersma, R. D.; Mao Weihua; Xing, L.

2008-01-01

In the presence of intrafraction organ motion, target localization uncertainty can greatly hamper the advantage of highly conformal dose techniques such as intensity modulated radiation therapy (IMRT). To minimize the adverse dosimetric effect caused by tumor motion, a real-time knowledge of the tumor position is required throughout the beam delivery process. The recent integration of onboard kV diagnostic imaging together with MV electronic portal imaging devices on linear accelerators can allow for real-time three-dimensional (3D) tumor position monitoring during a treatment delivery. The aim of this study is to demonstrate a near real-time 3D internal fiducial tracking system based on the combined use of kV and MV imaging. A commercially available radiotherapy system equipped with both kV and MV imaging systems was used in this work. A hardware video frame grabber was used to capture both kV and MV video streams simultaneously through independent video channels at 30 frames per second. The fiducial locations were extracted from the kV and MV images using a software tool. The geometric tracking capabilities of the system were evaluated using a pelvic phantom with embedded fiducials placed on a moveable stage. The maximum tracking speed of the kV/MV system is approximately 9 Hz, which is primarily limited by the frame rate of the MV imager. The geometric accuracy of the system is found to be on the order of less than 1 mm in all three spatial dimensions. The technique requires minimal hardware modification and is potentially useful for image-guided radiation therapy systems

Fluoroscopy-assisted vs fluoroless endoscopic ultrasound-guided transmural drainage of pancreatic fluid collections: A comparative study.

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Consiglieri, Claudia F; Gornals, Joan B; Busquets, Juli; Peláez, Nuria; Secanella, Lluis; De-La-Hera, Meritxell; Sanzol, Resurrección; Fabregat, Joan; Castellote, José

2018-01-01

The need for fluoroscopy guidance in patients undergoing endoscopic ultrasound-guided transmural drainage (EUS-TMD) of peripancreatic fluid collections (PFCs) remains unclear. The aim of this study was to compare general outcomes of EUS-TMD of PFCs under fluoroscopy (F) vs fluoroless (FL). This is a comparative study with a retrospective analysis of a prospective and consecutive inclusion database at a tertiary centre, from 2009 to 2015. All patients were symptomatic pseudocyst (PSC) and walled-off pancreatic necrosis (WON). Two groups were assigned depending on availability of fluoroscopy. The groups were heterogeneous in terms of their demographic characteristics, PFCs and procedure. The main outcome measures included technical and clinical success, incidences, adverse events (AEs), and follow-up. Fifty EUS-TMD of PFCs from 86 EUS-guided drainages were included during the study period. Group F included 26 procedures, PSC 69.2%, WON 30.8%, metal stents 61.5% (46.1% lumen-apposing stent) and plastic stents 38.5%. Group FL included 24 procedures, PSC 37.5%, WON 62.5%, and metal stents 95.8% (lumen-apposing stents). Technical success was 100% in both groups, and clinical success was similar (F 88.5%, FL 87.5%). Technical incidences and intra-procedure AEs were only described in group F (7.6% and 11.5%, respectively) and none in group FL. Procedure time was less in group FL (8min, p=0.0341). Fluoroless in the EUS-TMD of PFCs does not involve more technical incidences or intra-procedure AEs. Technical and clinical success was similar in the two groups. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

C-arm Cone Beam Computed Tomographic Needle Path Overlay for Fluoroscopic-Guided Placement of Translumbar Central Venous Catheters

International Nuclear Information System (INIS)

Tam, Alda; Mohamed, Ashraf; Pfister, Marcus; Rohm, Esther; Wallace, Michael J.

2009-01-01

C-arm cone beam computed tomography is an advanced 3D imaging technology that is currently available on state-of-the-art flat-panel-based angiography systems. The overlay of cross-sectional imaging information can now be integrated with real-time fluoroscopy. This overlay technology was used to guide the placement of three percutaneous translumbar inferior vena cava catheters.

Ultrasound-guided Placement of a Foley Catheter Using a Hydrophilic Guide Wire

Directory of Open Access Journals (Sweden)

Mark Huber

2018-03-01

Full Text Available Acute urinary retention is a common problem in the emergency department. Patients can present in significant distress, necessitating the placement of a urinary catheter. Foley catheter placement can be difficult to accomplish depending on the etiology of the retention and the degree of the obstruction. In the case presented here, we used ultrasound guidance, a guidewire, and a Foley catheter to successfully relieve a patient’s urinary retention after multiple failed attempts.

Clinical Usefulness of Implanted Fiducial Markers for Hypofractionated Radiotherapy of Prostate Cancer

International Nuclear Information System (INIS)

Choi, Young Min; Ahn, Sung Hwan; Lee, Hyung Hwan; Lee, Hyung Sik; Hur, Woo Joo; Yoon, Jin Han; Kim, Tae Hyo; Kim, Soo Dong; Yun, Seong Guk

2011-01-01

To assess the usefulness of implanted fiducial markers in the setup of hypofractionated radiotherapy for prostate cancer patients by comparing a fiducial marker matched setup with a pelvic bone match. Four prostate cancer patients treated with definitive hypofractionated radiotherapy between September 2009 and August 2010 were enrolled in this study. Three gold fiducial markers were implanted into the prostate and through the rectum under ultrasound guidance around a week before radiotherapy. Glycerin enemas were given prior to each radiotherapy planning CT and every radiotherapy session. Hypofractionated radiotherapy was planned for a total dose of 59.5 Gy in daily 3.5 Gy with using the Novalis system. Orthogonal kV X-rays were taken before radiotherapy. Treatment positions were adjusted according to the results from the fusion of the fiducial markers on digitally reconstructed radiographs of a radiotherapy plan with those on orthogonal kV X-rays. When the difference in the coordinates from the fiducial marker fusion was less than 1 mm, the patient position was approved for radiotherapy. A virtual bone matching was carried out at the fiducial marker matched position, and then a setup difference between the fiducial marker matching and bone matching was evaluated. Three patients received a planned 17-fractionated radiotherapy and the rest underwent 16 fractionations. The setup error of the fiducial marker matching was 0.94±0.62 mm (range, 0.09 to 3.01 mm; median, 0.81 mm), and the means of the lateral, craniocaudal, and anteroposterior errors were 0.39±0.34 mm, 0.46±0.34 mm, and 0.57±0.59 mm, respectively. The setup error of the pelvic bony matching was 3.15±2.03 mm (range, 0.25 to 8.23 mm; median, 2.95 mm), and the error of craniocaudal direction (2.29±1.95 mm) was significantly larger than those of anteroposterior (1.73±1.31 mm) and lateral directions (0.45±0.37 mm), respectively (p< 0.05). Incidences of over 3 mm and 5 mm in setup difference among the

EUS-guided biliary drainage by using a standardized approach for malignant biliary obstruction: rendezvous versus direct transluminal techniques (with videos).

Science.gov (United States)

Khashab, Mouen A; Valeshabad, Ali Kord; Modayil, Rani; Widmer, Jessica; Saxena, Payal; Idrees, Mehak; Iqbal, Shahzad; Kalloo, Anthony N; Stavropoulos, Stavros N

2013-11-01

EUS-guided biliary drainage (EGBD) can be performed via direct transluminal or rendezvous techniques. It is unknown how both techniques compare in terms of efficacy and adverse events. To describe outcomes of EGBD performed by using a standardized approach and compare outcomes of rendezvous and transluminal techniques. Retrospective analysis of prospectively collected data. Two tertiary-care centers. Consecutive jaundiced patients with distal malignant biliary obstruction who underwent EGBD after failed ERCP between July 2006 and December 2012 were included. EGBD by using a standardized algorithm. Technical success, clinical success, and adverse events. During the study period, 35 patients underwent EGBD (rendezvous n = 13, transluminal n = 20). Technical success was achieved in 33 patients (94%), and clinical success was attained in 32 of 33 patients (97.0%). The mean postprocedure bilirubin level was 1.38 mg/dL in the rendezvous group and 1.33 mg/dL in the transluminal group (P = .88). Similarly, length of hospital stay was not different between groups (P = .23). There was no significant difference in adverse event rate between rendezvous and transluminal groups (15.4% vs 10%; P = .64). Long-term outcomes were comparable between groups, with 1 stent migration in the rendezvous group at 62 days and 1 stent occlusion in the transluminal group at 42 days after EGBD. Retrospective analysis, small number of patients, and selection bias. EGBD is safe and effective when the described standardized approach is used. Stent occlusion is not common during long-term follow-up. Both rendezvous and direct transluminal techniques seem to be equally effective and safe. The latter approach is a reasonable alternative to rendezvous EGBD. Copyright © 2013. Published by Mosby, Inc.

Endoscopic ultrasonography-guided rendezvous technique.

Science.gov (United States)

Tsuchiya, Takayoshi; Itoi, Takao; Sofuni, Atsushi; Tonozuka, Ryosuke; Mukai, Shuntaro

2016-04-01

Endoscopic retrograde cholangiopancreatography (ERCP) requires deep biliary cannulation. When deep biliary cannulation is failed, the endoscopic ultrasonography rendezvous technique (EUS-RV) is a useful salvage method. From the previous 15 articles that included 382 EUS-RV cases, the overall success rate of EUS-RV is 81 % with a complication rate of 10 %. In EUS-RV, the bile duct is punctured under EUS guidance and a guidewire is advanced into the duodenum via the papilla. The EUS scope is then switched to a duodenoscope and inserted into the bile duct over the guidewire exiting the papilla, or the guidewire is grasped with forceps and passed through the working channel; the catheter can then be inserted through the papilla over the wire. There are three puncture routes for EUS-RV: transgastric puncture of the intrahepatic bile duct (IHBD), transduodenal puncture of the extrahepatic bile duct (EHBD) via the proximal duodenum (D1), and transduodenal puncture of the EHBD via the second portion of the duodenum (D2). The puncture route for each patient should be selected based on the patient condition. GW selection for EUS-RV is critical, a hydrophilic GW is useful for this procedure. Although EUS-RV is now performed relatively routinely in a few high-volume centers, procedure standardization and the development of exclusive devices for EUS-RV are still underway. The development of exclusive devices for EUS-RV and prospective comparative studies with other salvage methods are needed to truly evaluate the procedure's usefulness and safety.

Endoscopic ultrasound in the evaluation of chronic upper abdominal pain of unknown etiology: a retrospective chart review examining the efficacy of EUS in determining a new diagnosis.

Science.gov (United States)

Thompson, Michelle B; Ramirez, Jonathan C; De La Rosa, Lisa M; Wood, Adam S; Desai, Shiv; Arjunan, Ananth; Song, Juhee; Erickson, Richard A

2015-02-01

To explore the utility of endoscopic ultrasound (EUS) in the evaluation of chronic upper abdominal pain (UAP) of undetermined etiology. Chronic UAP is a common problem with a challenging diagnosis and management. The role of EUS in the diagnosis of UAP may minimize additional testing; however, few studies describe the percentage of new diagnoses yielded in these patients. We conducted a retrospective analysis by reviewing electronic medical records at Scott and White Memorial Hospital, Texas A&M Health Sciences Center for patients with abdominal pain for ≥ 12 months not explained by previous workup referred for EUS for chronic UAP from January 1, 1998 through October 1, 2007. Patients with previous EUS in past 12 months were excluded from the study. Patient demographic data and imaging performed 6 months before and 24 months after EUS were reviewed and results documented. EUS was successful at diagnosing a new clinical etiology of chronic UAP in 33 patients (8.89%) with previous workup that was unrevealing for a definitive diagnosis. The most frequent diagnoses included pancreaticobiliary tree abnormalities, chronic pancreatitis, and fatty liver disease. Our results support the fact that the majority of patients UAP with prior imaging will have no identifiable organic etiology found on EUS to explain their pain; however, we suggest that EUS be considered in patients with suspected pancreatic or biliary pathology.

Comparison of 22G reverse-beveled versus standard needle for endoscopic ultrasound-guided sampling of solid pancreatic lesions

Science.gov (United States)

Alatawi, Abdullah; Beuvon, Frédéric; Grabar, Sophie; Leblanc, Sarah; Chaussade, Stanislas; Terris, Benoit; Barret, Maximilien

2015-01-01

Objectives Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) using standard needles has a high diagnostic value in the evaluation of solid pancreatic masses. Fenestrated needles have been developed to improve the quality of EUS-guided tissue sampling by providing core biopsies (FNB). Methods Patients with solid pancreatic masses of >2 cm were prospectively included in our study and randomized to receive EUS sampling, using either a standard 22G FNA or a 22G Procore® FNB needle. The main study endpoint was the number of needle passes required to obtain a diagnosis in more than 90% of cases. Results We included 100 patients (male = 63, female = 37; mean age = 68.4 years) in our study. We found that 88% of the lesions were malignant, with a mean size of 32 mm. A sample adequate for diagnosis was obtained in more than 90% of cases after the second needle pass in the FNB group, versus the third needle pass in the FNA group. Slide cellularity and presence of tissue microfragments were significantly higher in the FNB group. Sensitivity for the diagnosis of malignancy was 88.4% versus 97.8% for the EUS-FNA and EUS-FNB group, respectively, while specificity for both techniques was 100%. No complications were recorded. Conclusions Although the accuracy of both needle types for proving malignancy was similar, a lower number of passes was required with the FNB needles to achieve the same contributive sample rate as with the FNA needles. FNB also improved the histopathological quality of specimens, suggesting an overall superiority of FNB sampling. PMID:26279842

Augmented Reality-Guided Lumbar Facet Joint Injections.

Science.gov (United States)

Agten, Christoph A; Dennler, Cyrill; Rosskopf, Andrea B; Jaberg, Laurenz; Pfirrmann, Christian W A; Farshad, Mazda

2018-05-08

The aim of this study was to assess feasibility and accuracy of augmented reality-guided lumbar facet joint injections. A spine phantom completely embedded in hardened opaque agar with 3 ring markers was built. A 3-dimensional model of the phantom was uploaded to an augmented reality headset (Microsoft HoloLens). Two radiologists independently performed 20 augmented reality-guided and 20 computed tomography (CT)-guided facet joint injections each: for each augmented reality-guided injection, the hologram was manually aligned with the phantom container using the ring markers. The radiologists targeted the virtual facet joint and tried to place the needle tip in the holographic joint space. Computed tomography was performed after each needle placement to document final needle tip position. Time needed from grabbing the needle to final needle placement was measured for each simulated injection. An independent radiologist rated images of all needle placements in a randomized order blinded to modality (augmented reality vs CT) and performer as perfect, acceptable, incorrect, or unsafe. Accuracy and time to place needles were compared between augmented reality-guided and CT-guided facet joint injections. In total, 39/40 (97.5%) of augmented reality-guided needle placements were either perfect or acceptable compared with 40/40 (100%) CT-guided needle placements (P = 0.5). One augmented reality-guided injection missed the facet joint space by 2 mm. No unsafe needle placements occurred. Time to final needle placement was substantially faster with augmented reality guidance (mean 14 ± 6 seconds vs 39 ± 15 seconds, P Augmented reality-guided facet joint injections are feasible and accurate without potentially harmful needle placement in an experimental setting.

Fiducial-based fusion of 3D dental models with magnetic resonance imaging.

Science.gov (United States)

Abdi, Amir H; Hannam, Alan G; Fels, Sidney

2018-04-16

Magnetic resonance imaging (MRI) is widely used in study of maxillofacial structures. While MRI is the modality of choice for soft tissues, it fails to capture hard tissues such as bone and teeth. Virtual dental models, acquired by optical 3D scanners, are becoming more accessible for dental practice and are starting to replace the conventional dental impressions. The goal of this research is to fuse the high-resolution 3D dental models with MRI to enhance the value of imaging for applications where detailed analysis of maxillofacial structures are needed such as patient examination, surgical planning, and modeling. A subject-specific dental attachment was digitally designed and 3D printed based on the subject's face width and dental anatomy. The attachment contained 19 semi-ellipsoidal concavities in predetermined positions where oil-based ellipsoidal fiducial markers were later placed. The MRI was acquired while the subject bit on the dental attachment. The spatial position of the center of mass of each fiducial in the resultant MR Image was calculated by averaging its voxels' spatial coordinates. The rigid transformation to fuse dental models to MRI was calculated based on the least squares mapping of corresponding fiducials and solved via singular-value decomposition. The target registration error (TRE) of the proposed fusion process, calculated in a leave-one-fiducial-out fashion, was estimated at 0.49 mm. The results suggest that 6-9 fiducials suffice to achieve a TRE of equal to half the MRI voxel size. Ellipsoidal oil-based fiducials produce distinguishable intensities in MRI and can be used as registration fiducials. The achieved accuracy of the proposed approach is sufficient to leverage the merged 3D dental models with the MRI data for a finer analysis of the maxillofacial structures where complete geometry models are needed.

Failed common bile duct cannulation during pregnancy: Rescue with endoscopic ultrasound guided rendezvous procedure.

Science.gov (United States)

Singla, Vikas; Arora, Anil; Tyagi, Pankaj; Sharma, Praveen; Bansal, Naresh; Kumar, Ashish

2016-01-01

Common bile duct (CBD) stones can lead to serious complications and require intervention with either endoscopic retrograde cholangiopancreatography (ERCP) or laparoscopic techniques for urgent relief. On an average 10%-20% of the patients with gall bladder stones can have associated CBD stones. CBD stones during pregnancy can be associated with hazardous complications for both the mother and the fetus. Failed cannulation while performing ERCP during pregnancy is a technically demanding situation, which requires immediate rescue with special techniques. Conventional rescue techniques may not be feasible and can be associated with hazardous consequences. Endoscopic ultrasound (EUS) guided rendezvous technique has now emerged as a safe alternative, and in one of our patients, this technique was successfully attempted. To the best of our knowledge, this is the first case report in the literature on EUS-guided rendezvous procedure during pregnancy.

Can a Drill Guide Improve the Coracoid Graft Placement During the Latarjet Procedure? A Prospective Comparative Study With the Freehand Technique.

Science.gov (United States)

Barth, Johannes; Boutsiadis, Achilleas; Neyton, Lionel; Lafosse, Laurent; Walch, Gilles

2017-10-01

One of the factors that can affect the success of the Latarjet procedure is accurate coracoid graft (CG) placement. The use of a guide can improve placement of the CG and screw positioning in the sagittal and axial planes as compared with the classic open ("freehand") technique. Cohort study; Level of evidence, 2. A total of 49 patients who underwent a Latarjet procedure for the treatment of recurrent anterior shoulder instability were prospectively included; the procedure was performed with the freehand technique in 22 patients (group 1) and with use of a parallel drill guide during screw placement in 27 patients (group 2). All patients underwent a postoperative computed tomography scan with the same established protocol. The scans were used to evaluate and compare the position of the CG in the sagittal and axial planes, the direction of the screws (α angle), and overall contact of the graft with the anterior surface of the glenoid after the 2 surgical techniques. The CG was placed >60% below the native glenoid equator in 23 patients (85.2%) in group 2, compared with 14 patients (63.6%) in group 1 ( P = .004). In the axial plane, the position of the CG in group 2 patients was more accurate (85.2% and 88.9% flush) at the inferior and middle quartiles of the glenoid surface ( P = .012 and .009), respectively. Moreover, with the freehand technique (group 1), the graft was in a more lateral position in the inferior and middle quartiles ( P = .012 and .009, respectively). No differences were found between groups 1 and 2 regarding the mean α angle of the superior (9° ± 4.14° vs 11° ± 6.3°, P = .232) and inferior (9.5° ± 6° vs 10° ± 7.5°, P = .629) screws. However, the mean contact angle (angle between the posterior coracoid and the anterior glenoid surface) with the freehand technique (3.8° ± 6.8°) was better than that of the guide (8.55° ± 8°) ( P = .05). Compared with the classic freehand operative technique, the parallel drill guide can ensure

BIBLIOGRAPHIC GUIDE FOR ADVANCED PLACEMENT, LATIN.

Science.gov (United States)

BARRON, ROBERT; ROSELLE, LEONE

LITERARY AND CRITICAL WORKS, REFERENCE BOOKS, PERIODICALS, RECORDS, FILMS, AND FILMSTRIPS DEALING WITH ROMAN LITERATURE, HISTORY, CIVILIZATION, MYTHOLOGY, AND LANGUAGE ARE INCLUDED IN THIS BIBLIOGRAPHY OF RECOMMENDED READING IN ENGLISH FOR ADVANCED PLACEMENT PROGRAMS IN LATIN. THE LIST IS DIVIDED INTO TWO $500 GROUPS, SO THAT FOR CONVENIENCE IN…

Therapeutic aspects of endoscopic ultrasound

Science.gov (United States)

Woodward, Timothy A.

1999-06-01

Endoscopic ultrasound (EUS) is a technology that had been used primarily as a passive imaging modality. Recent advances have enabled us to move beyond the use of EUS solely as a staging tool to an interventional device. Current studies suggest that interventional applications of EUS will allow for minimally invasive assessment and therapies in a cost-effective manner. Endoscopic ultrasound with fine needle aspiration (EUS-FNA) has been demonstrated to be a technically feasible, relatively safe method of obtaining cytologic specimens. The clinical utility of EUS- FNA appears to be greatest in the diagnosis and staging of pancreatic cancer and in the nodal staging of gastrointestinal and pulmonary malignancies. In addition, EUS-FNA has demonstrated utility in the sampling pleural and ascitic fluid not generally appreciated or assessable to standard interventions. Interventional applications of EUS include EUS-guided pseudocyst drainage, EUS-guided injection of botulinum toxin in the treatment of achalasia, and EUS- guided celiac plexus neurolysis in the treatment of pancreatic cancer pain. Finally, EUS-guided fine-needle installation is being evaluated, in conjunction with recent bimolecular treatment modalities, as a delivery system in the treatment of certain gastrointestinal tumors.

Endoscopic ultrasound-guided radiofrequency ablation for management of benign solid pancreatic tumors.

Science.gov (United States)

Choi, Jun-Ho; Seo, Dong-Wan; Song, Tae Jun; Park, Do Hyun; Lee, Sang Soo; Lee, Sung Koo; Kim, Myung-Hwan

2018-05-04

 Radiofrequency ablation (RFA) has been increasingly employed in experimental and clinical settings for the management of pancreatic lesions. This study aimed to assess the safety and efficacy of endoscopic ultrasound (EUS)-guided RFA for benign solid pancreatic tumors.  In a single-center, prospective study, 10 patients with benign solid pancreatic tumors underwent EUS-RFA. After the RFA electrode had been inserted into the pancreatic mass, the radiofrequency generator was activated to deliver 50 W of ablation power.  Among the 10 patients, 16 sessions of EUS-RFA were successfully performed. Diagnoses included nonfunctioning neuroendocrine tumor (n = 7), solid pseudopapillary neoplasm (n = 2), and insulinoma (n = 1); the median largest diameter of the tumors was 20 mm (range 8 - 28 mm). During follow-up (median 13 months), radiologic complete response was achieved in seven patients. Two adverse events (12.4 %; 1 moderate and 1 mild) occurred.  EUS-RFA may be a safe and potentially effective treatment option in selected patients with benign solid pancreatic tumors. Multiple sessions may be required if there is a remnant tumor, and adverse events must be carefully monitored. © Georg Thieme Verlag KG Stuttgart · New York.

Body-mounted robotic instrument guide for image-guided cryotherapy of renal cancer

Science.gov (United States)

Hata, Nobuhiko; Song, Sang-Eun; Olubiyi, Olutayo; Arimitsu, Yasumichi; Fujimoto, Kosuke; Kato, Takahisa; Tuncali, Kemal; Tani, Soichiro; Tokuda, Junichi

2016-01-01

Purpose: Image-guided cryotherapy of renal cancer is an emerging alternative to surgical nephrectomy, particularly for those who cannot sustain the physical burden of surgery. It is well known that the outcome of this therapy depends on the accurate placement of the cryotherapy probe. Therefore, a robotic instrument guide may help physicians aim the cryotherapy probe precisely to maximize the efficacy of the treatment and avoid damage to critical surrounding structures. The objective of this paper was to propose a robotic instrument guide for orienting cryotherapy probes in image-guided cryotherapy of renal cancers. The authors propose a body-mounted robotic guide that is expected to be less susceptible to guidance errors caused by the patient’s whole body motion. Methods: Keeping the device’s minimal footprint in mind, the authors developed and validated a body-mounted, robotic instrument guide that can maintain the geometrical relationship between the device and the patient’s body, even in the presence of the patient’s frequent body motions. The guide can orient the cryotherapy probe with the skin incision point as the remote-center-of-motion. The authors’ validation studies included an evaluation of the mechanical accuracy and position repeatability of the robotic instrument guide. The authors also performed a mock MRI-guided cryotherapy procedure with a phantom to compare the advantage of robotically assisted probe replacements over a free-hand approach, by introducing organ motions to investigate their effects on the accurate placement of the cryotherapy probe. Measurements collected for performance analysis included accuracy and time taken for probe placements. Multivariate analysis was performed to assess if either or both organ motion and the robotic guide impacted these measurements. Results: The mechanical accuracy and position repeatability of the probe placement using the robotic instrument guide were 0.3 and 0.1 mm, respectively, at a depth

A fiducial skull marker for precise MRI-based stereotaxic surgery in large animal models.

Science.gov (United States)

Glud, Andreas Nørgaard; Bech, Johannes; Tvilling, Laura; Zaer, Hamed; Orlowski, Dariusz; Fitting, Lise Moberg; Ziedler, Dora; Geneser, Michael; Sangill, Ryan; Alstrup, Aage Kristian Olsen; Bjarkam, Carsten Reidies; Sørensen, Jens Christian Hedemann

2017-06-15

Stereotaxic neurosurgery in large animals is used widely in different sophisticated models, where precision is becoming more crucial as desired anatomical target regions are becoming smaller. Individually calculated coordinates are necessary in large animal models with cortical and subcortical anatomical differences. We present a convenient method to make an MRI-visible skull fiducial for 3D MRI-based stereotaxic procedures in larger experimental animals. Plastic screws were filled with either copper-sulfate solution or MRI-visible paste from a commercially available cranial head marker. The screw fiducials were inserted in the animal skulls and T1 weighted MRI was performed allowing identification of the inserted skull marker. Both types of fiducial markers were clearly visible on the MRÍs. This allows high precision in the stereotaxic space. The use of skull bone based fiducial markers gives high precision for both targeting and evaluation of stereotaxic systems. There are no metal artifacts and the fiducial is easily removed after surgery. The fiducial marker can be used as a very precise reference point, either for direct targeting or in evaluation of other stereotaxic systems. Copyright © 2017 Elsevier B.V. All rights reserved.

Filling a Plastic Bag with Carbon Dioxide: A Student-Designed Guided-Inquiry Lab for Advanced Placement and College Chemistry Courses

Science.gov (United States)

Lanni, Laura M.

2014-01-01

A guided-inquiry lab, suitable for first-year general chemistry or high school advanced placement chemistry, is presented that uses only inexpensive, store-bought materials. The reaction of sodium bicarbonate (baking soda) with aqueous acetic acid (vinegar), under the constraint of the challenge to completely fill a sealable plastic bag with the…

Technique of Injection of Hyaluronic Acid as a Prostatic Spacer and Fiducials Before Hypofractionated External Beam Radiotherapy for Prostate Cancer.

Science.gov (United States)

Boissier, Romain; Udrescu, Corina; Rebillard, Xavier; Terrier, Jean-Etienne; Faix, Antoine; Chapet, Olivier; Azria, David; Devonec, Marian; Paparel, Philippe; Ruffion, Alain

2017-01-01

To describe a technique combining the implantation of fiducials and a prostatic spacer (hyaluronic acid [HA]) to decrease the rectal toxicity after an image-guided external beam radiotherapy (EBRT) with hypofractionation for prostate cancer and to assess the tolerance and the learning curve of the procedure. Thirty patients with prostate cancer at low or intermediate risk were included in a phase II trial: image-guided EBRT of 62 Gy in 20 fractions of 3.1 Gy with intensity-modulated radiotherapy. A transrectal implantation of 3 fiducials and transperineal injection of 10 cc of HA (NASHA gel spacer, Q-Med AB, Uppsala, Sweden) between the rectum and the prostate was performed by 1 operator. The thickness of HA was measured at 10 points on magnetic resonance imaging to establish a quality score of the injection (maximum score = 10) and determine the learning curve of the procedure. The quality score increased from patients 1-10, 11-20, to 21-30 with respective median scores: 7 [2-10], 5 [4-7], and 8 [3-10]. The average thicknesses of HA between the base, middle part, and apex of the prostate and the rectum were the following: 15.1 mm [6.4-29], 9.8 mm [5-21.2], and 9.9 mm [3.2-21.5]. The injection of the HA induced a median pain score of 4 [1-8] and no residual pain at mid-long term. Creating an interface between the rectum and the prostate and the implantation of fiducials were feasible under local anesthesia with a short learning curve and could become a standard procedure before a hypofractionated EBRT for prostate cancer. Copyright © 2016 Elsevier Inc. All rights reserved.

Dosimetric adaptive IMRT driven by fiducial points

International Nuclear Information System (INIS)

Crijns, Wouter; Van Herck, Hans; Defraene, Gilles; Van den Bergh, Laura; Haustermans, Karin; Slagmolen, Pieter; Maes, Frederik; Van den Heuvel, Frank

2014-01-01

Purpose: Intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy have become standard treatments but are more sensitive to anatomical variations than 3D conformal techniques. To correct for inter- and intrafraction anatomical variations, fast and easy to implement methods are needed. Here, the authors propose a full dosimetric IMRT correction that finds a compromise in-between basic repositioning (the current clinical practice) and full replanning. It simplifies replanning by avoiding a recontouring step and a full dose calculation. It surpasses repositioning by updating the preoptimized fluence and monitor units (MU) using a limited number of fiducial points and a pretreatment (CB)CT. To adapt the fluence the fiducial points were projected in the beam's eye view (BEV). To adapt the MUs, point dose calculation towards the same fiducial points were performed. The proposed method is intrinsically fast and robust, and simple to understand for operators, because of the use of only four fiducial points and the beam data based point dose calculations. Methods: To perform our dosimetric adaptation, two fluence corrections in the BEV are combined with two MU correction steps along the beam's path. (1) A transformation of the fluence map such that it is realigned with the current target geometry. (2) A correction for an unintended scaling of the penumbra margin when the treatment beams scale to the current target size. (3) A correction for the target depth relative to the body contour and (4) a correction for the target distance to the source. The impact of the correction strategy and its individual components was evaluated by simulations on a virtual prostate phantom. This heterogeneous reference phantom was systematically subjected to population based prostate transformations to simulate interfraction variations. Additionally, a patient example illustrated the clinical practice. The correction strategy was evaluated using both dosimetric

Dosimetric adaptive IMRT driven by fiducial points

Energy Technology Data Exchange (ETDEWEB)

Crijns, Wouter, E-mail: wouter.crijns@uzleuven.be [Department of Oncology, Laboratory of Experimental Radiotherapy, KU Leuven, Herestraat 49, 3000 Leuven, Belgium and Medical Imaging Research Center, KU Leuven, Herestraat 49, 3000 Leuven (Belgium); Van Herck, Hans [Medical Imaging Research Center, KU Leuven, Herestraat 49, 3000 Leuven, Belgium and Department of Electrical Engineering (ESAT) – PSI, Center for the Processing of Speech and Images, KU Leuven, 3000 Leuven (Belgium); Defraene, Gilles; Van den Bergh, Laura; Haustermans, Karin [Department of Oncology, Laboratory of Experimental Radiotherapy, KU Leuven, Herestraat 49, 3000 Leuven (Belgium); Slagmolen, Pieter [Medical Imaging Research Center, KU Leuven, Herestraat 49, 3000 Leuven (Belgium); Department of Electrical Engineering (ESAT) – PSI, Center for the Processing of Speech and Images, KU Leuven, 3000 Leuven (Belgium); iMinds-KU Leuven Medical IT Department, KU Leuven, 3000 Leuven (Belgium); Maes, Frederik [Medical Imaging Research Center, KU Leuven, Herestraat 49, 3000 Leuven (Belgium); Department of Electrical Engineering (ESAT) – PSI, Center for the Processing of Speech and Images, KU Leuven and iMinds, 3000 Leuven (Belgium); Van den Heuvel, Frank [Department of Oncology, Laboratory of Experimental Radiotherapy, KU Leuven, Herestraat 49, 3000 Leuven, Belgium and Department of Oncology, MRC-CR-UK Gray Institute of Radiation Oncology and Biology, University of Oxford, Oxford OX1 2JD (United Kingdom)

2014-06-15

Purpose: Intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy have become standard treatments but are more sensitive to anatomical variations than 3D conformal techniques. To correct for inter- and intrafraction anatomical variations, fast and easy to implement methods are needed. Here, the authors propose a full dosimetric IMRT correction that finds a compromise in-between basic repositioning (the current clinical practice) and full replanning. It simplifies replanning by avoiding a recontouring step and a full dose calculation. It surpasses repositioning by updating the preoptimized fluence and monitor units (MU) using a limited number of fiducial points and a pretreatment (CB)CT. To adapt the fluence the fiducial points were projected in the beam's eye view (BEV). To adapt the MUs, point dose calculation towards the same fiducial points were performed. The proposed method is intrinsically fast and robust, and simple to understand for operators, because of the use of only four fiducial points and the beam data based point dose calculations. Methods: To perform our dosimetric adaptation, two fluence corrections in the BEV are combined with two MU correction steps along the beam's path. (1) A transformation of the fluence map such that it is realigned with the current target geometry. (2) A correction for an unintended scaling of the penumbra margin when the treatment beams scale to the current target size. (3) A correction for the target depth relative to the body contour and (4) a correction for the target distance to the source. The impact of the correction strategy and its individual components was evaluated by simulations on a virtual prostate phantom. This heterogeneous reference phantom was systematically subjected to population based prostate transformations to simulate interfraction variations. Additionally, a patient example illustrated the clinical practice. The correction strategy was evaluated using both dosimetric

Fiducialization of the small-aperture quadrupoles based on the vibrating wire method

Energy Technology Data Exchange (ETDEWEB)

Wang, Baichuan, E-mail: wangbaichuan@nint.ac.cn [State Key Laboratory of Intense Pulsed Radiation Simulation and Effect (Northwest Institute of Nuclear Technology), Xi' an 710024 (China); Tsinghua University, Beijing 100084 (China); Zheng, Shuxin, E-mail: zhengsx@tsinghua.edu.cn [Tsinghua University, Beijing 100084 (China); Wu, Lin; Du, Changtong; Xing, Qingzi [Tsinghua University, Beijing 100084 (China); Wang, Zhongming; Qiu, Mengtong [State Key Laboratory of Intense Pulsed Radiation Simulation and Effect (Northwest Institute of Nuclear Technology), Xi' an 710024 (China); Wang, Xuewu [Tsinghua University, Beijing 100084 (China)

2016-03-11

A fiducialization method based on vibrating wire is described dedicated to the problem of locating the magnetic center relative to external fiducials for the small-aperture quadrupoles. The advantage of this method is that the measurement of the wire position, which may be the main error source, is no longer needed. The position of the magnetic center can be directly obtained by measuring the position shift of the magnet fiducials. This method has been validated on small Permanent Magnet Quadrupoles (PMQs). Experiments have confirmed its feasibility of measuring PMQs with good repeatability of about 10 μm, and shown its high sensitivity as well as convenience.

CT fluoroscopy-guided preoperative short hook wire placement for small pulmonary lesions: evaluation of safety and identification of risk factors for pneumothorax

Energy Technology Data Exchange (ETDEWEB)

Iguchi, Toshihiro; Hiraki, Takao; Gobara, Hideo; Fujiwara, Hiroyasu; Matsui, Yusuke; Kanazawa, Susumu [Okayama University Medical School, Departments of Radiology, Okayama (Japan); Miyoshi, Shinichiro [Okayama University Medical School, General Thoracic Surgery, Okayama (Japan)

2016-01-15

To retrospectively evaluate the safety of computed tomography (CT) fluoroscopy-guided short hook wire placement for video-assisted thoracoscopic surgery and the risk factors for pneumothorax associated with this procedure. We analyzed 267 short hook wire placements for 267 pulmonary lesions (mean diameter, 9.9 mm). Multiple variables related to the patients, lesions, and procedures were assessed to determine the risk factors for pneumothorax. Complications (219 grade 1 and 4 grade 2 adverse events) occurred in 196 procedures. No grade 3 or above adverse events were observed. Univariate analysis revealed increased vital capacity (odds ratio [OR], 1.518; P = 0.021), lower lobe lesion (OR, 2.343; P = 0.001), solid lesion (OR, 1.845; P = 0.014), prone positioning (OR, 1.793; P = 0.021), transfissural approach (OR, 11.941; P = 0.017), and longer procedure time (OR, 1.036; P = 0.038) were significant predictors of pneumothorax. Multivariate analysis revealed only the transfissural approach (OR, 12.171; P = 0.018) and a longer procedure time (OR, 1.048; P = 0.012) as significant independent predictors. Complications related to CT fluoroscopy-guided preoperative short hook wire placement often occurred, but all complications were minor. A transfissural approach and longer procedure time were significant independent predictors of pneumothorax. (orig.)

CT fluoroscopy-guided preoperative short hook wire placement for small pulmonary lesions: evaluation of safety and identification of risk factors for pneumothorax

International Nuclear Information System (INIS)

Iguchi, Toshihiro; Hiraki, Takao; Gobara, Hideo; Fujiwara, Hiroyasu; Matsui, Yusuke; Kanazawa, Susumu; Miyoshi, Shinichiro

2016-01-01

To retrospectively evaluate the safety of computed tomography (CT) fluoroscopy-guided short hook wire placement for video-assisted thoracoscopic surgery and the risk factors for pneumothorax associated with this procedure. We analyzed 267 short hook wire placements for 267 pulmonary lesions (mean diameter, 9.9 mm). Multiple variables related to the patients, lesions, and procedures were assessed to determine the risk factors for pneumothorax. Complications (219 grade 1 and 4 grade 2 adverse events) occurred in 196 procedures. No grade 3 or above adverse events were observed. Univariate analysis revealed increased vital capacity (odds ratio [OR], 1.518; P = 0.021), lower lobe lesion (OR, 2.343; P = 0.001), solid lesion (OR, 1.845; P = 0.014), prone positioning (OR, 1.793; P = 0.021), transfissural approach (OR, 11.941; P = 0.017), and longer procedure time (OR, 1.036; P = 0.038) were significant predictors of pneumothorax. Multivariate analysis revealed only the transfissural approach (OR, 12.171; P = 0.018) and a longer procedure time (OR, 1.048; P = 0.012) as significant independent predictors. Complications related to CT fluoroscopy-guided preoperative short hook wire placement often occurred, but all complications were minor. A transfissural approach and longer procedure time were significant independent predictors of pneumothorax. (orig.)

Safe and successful endoscopic initial treatment and long-term eradication of gastric varices by endoscopic ultrasound-guided Histoacryl (N-butyl-2-cyanoacrylate) injection.

Science.gov (United States)

Gubler, Christoph; Bauerfeind, Peter

2014-09-01

Optimal endoscopic treatment of gastric varices is still not standardized nowadays. Actively bleeding varices may prohibit a successful endoscopic injection therapy of Histoacryl® (N-butyl-2-cyanoacrylate). Since 2006, we have treated gastric varices by standardized endoscopic ultrasound (EUS) guided Histoacryl injection therapy without severe adverse events. We present a large single-center cohort over 7 years with a standardized EUS-guided sclerotherapy of all patients with gastric varices. Application was controlled by fluoroscopy to immediately detect any glue embolization. Only perforating veins located within the gastric wall were treated. In the follow up, we repeated this treatment until varices were eradicated. Utmost patients (36 of 40) were treated during or within 24 h of active bleeding. About 32.5% of patients were treated while visible bleeding. Histoacryl injection was always technically successful and only two patients suffered a minor complication. Acute bleeding was stopped in all patients. About 15% (6 of 40) of patients needed an alternative rescue treatment in the longer course. Three patients got a transjugular portosystemic shunt and another three underwent an orthotopic liver transplantation. Mean long-term survival of 60 months was excellent. Active bleeding of gastric varices can be treated successfully without the necessity of gastric rinsing with EUS-guided injection of Histoacryl.

Image guided surgery for petrous apex lesions

International Nuclear Information System (INIS)

Van Havenbergh, T.; De Ridder, D.; Verlooy, J.; Koekelkoren, E.; Van De Heyning, P.

2003-01-01

To evaluate whether computer-assisted frameless stereotactic navigation in the temporal bone provides sufficient clinical application accuracy and thus a useful tool in temporal bone surgery. Two patients with petrous apex cholesterol granuloma were operated on by an epidural middle fossa approach using a Stealth/MedtronicTM neuronavigation system. Based an literature data optimal skin fiducial placement and registration methods were used. Intra-operative accuracy was checked using three precise anatomical landmarks. Drilling of the petrotis apex bone was guided by neuronavigation. Postoperative Computed Tomography (CT) images were fused with the preoperative CT and planning. The application of image-guidance in temporal bone surgery causes no additional burden to the patient nor prolongs the operating time. The accuracy measured at the anatomical landmarks was under 2,0 mm. This is confirmed by evaluation of bone removal through image fusion of pre- and postoperative CT scan. The clinical application of a neuronavigation system during petrous apex surgery can be regarded as useful. Using all available data on registration methods it seems possible to obtain intra-operative application accuracies of < 2,0 mm. Additional cadaver work is being performed to support these data. (author)

Percutaneous Placement of Central Venous Catheters: Comparing the Anatomical Landmark Method with the Radiologically Guided Technique for Central Venous Catheterization Through the Internal Jugular Vein in Emergent Hemodialysis Patients

Energy Technology Data Exchange (ETDEWEB)

Koroglu, M.; Demir, M.; Koroglu, B.K.; Sezer, M.T.; Akhan, O.; Yildiz, H.; Yavuz, L.; Baykal, B.; Oyar, O. [Suleyman Demirel Univ., Isparta (Turkey). Depts. of Radiology, Internal Medicine and Anesthesiology

2006-02-15

Purpose: To compare the success and immediate complication rates of the anatomical landmark method (group 1) and the radiologically (combined real-time ultrasound and fluoroscopy) guided technique (group 2) in the placement of central venous catheters in emergent hemodialysis patients. Material and Methods: The study was performed prospectively in a randomized manner. The success and immediate complication rates of radiologically guided placement of central venous access catheters through the internal jugular vein (n = 40) were compared with those of the anatomical landmark method (n 40). The success of placement, the complications, the number of passes required, and whether a single or double-wall puncture occurred were also noted and compared. Results: The groups were comparable in age and sex. The indication for catheter placement was hemodialysis access in all patients. Catheter placement was successful in all patients in group 2 and unsuccessful in 1 (2.5%) patient in group 1. All catheters functioned adequately and immediately after the placement (0% initial failure rate) in group 2, but 3 catheters (7.5% initial failure rate) were non-functional just after placement in group 1. The total number of needle passes, double venous wall puncture, and complication rate were significantly lower in group 2. Conclusion: Percutaneous central venous catheterization via the internal jugular vein can be performed by interventional radiologists with better technical success rates and lower immediate complications. In conclusion, central venous catheterization for emergent dialysis should be performed under both real-time ultrasound and fluoroscopic guidance.

Clinical outcomes of image guided radiation therapy (IGRT) with gold fiducial vaginal cuff markers for high-risk endometrial cancer

Energy Technology Data Exchange (ETDEWEB)

Monroe, Alan T.; Peddada, Anuj V. [Dept. of Radiation Oncology, Penrose Cancer Center, Colorado Springs (United States); Pikaart, Dirk [Dept. of Gynecologic Oncology, Penrose Cancer Center, Colorado Springs (United States)

2013-06-15

Objective. To report two year clinical outcomes of image guided radiation therapy (IGRT) to the vaginal cuff and pelvic lymph nodes in a series of high-risk endometrial cancer patients. Methods . Twenty-six consecutive high-risk endometrial cancer patients requiring adjuvant radiation to the vaginal cuff and regional lymph nodes were treated with vaginal cuff fiducial-based IGRT. Seventeen (65%) received sequential chemotherapy, most commonly with a sandwich technique. Brachytherapy followed external radiation in 11 patients to a median dose of 18 Gy in 3 fractions. The median external beam dose delivered was 47.5 Gy in 25 fractions. Results. All 656 fractions were successfully imaged and treated. The median overall translational shift required for correction was 9.1 mm (standard deviation, 5.2 mm) relative to clinical set-up with skin tattoos. Shifts of 1 cm, 1.5 cm, and 2 cm or greater were performed in 43%, 14%, and 4% of patients, respectively. Acute grade 2 gastrointestinal (GI) toxicity occurred in eight patients (30%) and grade 3 toxicity occurred in one. At two years, there have been no local or regional failures and actuarial overall survival is 95%. Conclusion. Daily image guidance for high-risk endometrial cancer results in a low incidence of acute GI/genitourinary (GU) toxicity with uncompromised tumor control at two years. Vaginal cuff translations can be substantial and may possibly result in underdosing if not properly considered.

Clinical outcomes of image guided radiation therapy (IGRT) with gold fiducial vaginal cuff markers for high-risk endometrial cancer

International Nuclear Information System (INIS)

Monroe, Alan T.; Peddada, Anuj V.; Pikaart, Dirk

2013-01-01

Objective. To report two year clinical outcomes of image guided radiation therapy (IGRT) to the vaginal cuff and pelvic lymph nodes in a series of high-risk endometrial cancer patients. Methods . Twenty-six consecutive high-risk endometrial cancer patients requiring adjuvant radiation to the vaginal cuff and regional lymph nodes were treated with vaginal cuff fiducial-based IGRT. Seventeen (65%) received sequential chemotherapy, most commonly with a sandwich technique. Brachytherapy followed external radiation in 11 patients to a median dose of 18 Gy in 3 fractions. The median external beam dose delivered was 47.5 Gy in 25 fractions. Results. All 656 fractions were successfully imaged and treated. The median overall translational shift required for correction was 9.1 mm (standard deviation, 5.2 mm) relative to clinical set-up with skin tattoos. Shifts of 1 cm, 1.5 cm, and 2 cm or greater were performed in 43%, 14%, and 4% of patients, respectively. Acute grade 2 gastrointestinal (GI) toxicity occurred in eight patients (30%) and grade 3 toxicity occurred in one. At two years, there have been no local or regional failures and actuarial overall survival is 95%. Conclusion. Daily image guidance for high-risk endometrial cancer results in a low incidence of acute GI/genitourinary (GU) toxicity with uncompromised tumor control at two years. Vaginal cuff translations can be substantial and may possibly result in underdosing if not properly considered

A Comparison of Endoscopic Ultrasound Guided Biopsy and Positron Emission Tomography with Integrated Computed Tomography in Lung Cancer Staging

DEFF Research Database (Denmark)

Larsen, Stine Schmidt; Vilmann, P; Krasnik, K

2009-01-01

BACKGROUND AND STUDY AIMS: Exact staging of patients with non-small-cell lung cancer (NSCLC) is important to improve selection of resectable and curable patients for surgery. Positron emission tomography with integrated computed tomography (PET/CT) and endoscopic ultrasound guided fine needle...... aspiration biopsy (EUS-FNA) are new and promising methods, but indications in lung cancer staging are controversial. Only few studies have compared the 2 methods. The aim of this study was to assess and compare the diagnostic values of PET/CT and EUS-FNA for diagnosing advanced lung cancer in patients, who...... had both procedures performed. PATIENTS AND METHODS: 27 patients considered to be potential candidates for resection of NSCLC underwent PET/CT and EUS-FNA. Diagnoses were confirmed either by open thoracotomy, mediastinoscopy or clinical follow-up. Advanced lung cancer was defined as tumour...

Developing Federated Services within Seismology: IRIS' involvement in the CoopEUS Project

Science.gov (United States)

Ahern, T. K.; Trabant, C. M.; Stults, M.

2014-12-01

As a founding member of the CoopEUS initiative, IRIS Data Services has partnered with five data centers in Europe and the UC Berkeley (NCEDC) in the US to implement internationally standardized web services to access seismological data using identical methodologies. The International Federation of Digital Seismograph Networks (FDSN) holds commission status within IASPEI/IUGG and as such is the international body that governs data exchange formats and access protocols within seismology. The CoopEUS project involves IRIS and UNAVCO as part of the EarthScope project and the European collaborators are all members of the European Plate Observing System (EPOS). CoopEUS includes one work package that attempts to coordinate data access between EarthScope and EPOS facilities. IRIS has worked with its partners in the FDSN to develop and adopt three key international service standards within seismology. These include 1) fdsn-dataselect, a service that returns time series data in a variety of standard formats, 2) fdsn-station, a service that returns related metadata about a seismic station in stationXML format, and 3) fdsn-event, a service that returns information about earthquakes and other seismic events in QuakeML format. Currently the 5 European data centers supporting these services include the ORFEUS Data Centre in the Netherlands, the GFZ German Research Centre for Geosciences in Potsdam, Germany, ETH Zurich in Switzerland, INGV in Rome, Italy, and the RESIF Data Centre in Grenoble France. Presently these seven centres can all be accessed using standardized web services with identical service calls and returns results in standardized ways. IRIS is developing an IRIS federator that will allow a client to seamlessly access information across the federated centers. Details and current status of the IRIS Federator will be presented.

SQUID magnetometry and magneto-optics of epitaxial EuS

International Nuclear Information System (INIS)

Rumpf, K.; Granitzer, P.; Krenn, H.; Kellner, W.; Pascher, H.; Kirchschlager, R.; Janecek, S.

2004-01-01

The complicated (H,T)-magnetic phase diagram of EuS is caused by the critical balance between nearest and next nearest neighbour exchange interaction (J NN = 0.119 K and J NNN =-0.1209 K) and leads to various spin arrangements NNSS..., NSN..., NNS, NNN... [NS denotes opposite ferromagnetic order in adjacent (111) planes]. Beside the subtle local exchange of 5d-t 2g electrons and localized holes with neighbouring Eu-4f spins, obviously also the strain status influences the occurrence of these different phases. We investigate the magnetic ordering phenomenon in a strained 2.5 μm EuS film on BaF 2 substrate by SQUID magnetometry and magneto-optics like spectral Faraday- and Kerr-effect measurements for temperatures from 2 K up to 200 K and for magnetic field up to 5 T. The magneto-optical probe monitors the local environment of the photoexcited electron-hole pair, called magnetic exciton, located within a ferromagnetic surrounding (photoinduced magnetic polaron), whereas the integral magnetization measured by SQUID is most sensitive to long-range magnetic ordering. In spite of the dissimilarity of measurement techniques we find an influence of the long-range magnetic order (e.g. of the NNS- or NNN-matrix) on the non-resonant Kerr reflection. The complementarity of SQUID and magneto-optical methods is stringent only in the (resonant) spectral range, where magnetic polarons are formed. (author)

Endoscopic ultrasound-guided fine-needle aspiration cytology in the evaluation of suspected tuberculosis in patients with isolated mediastinal lymphadenopathy

DEFF Research Database (Denmark)

Puri, R.; Vilmann, P.; Sud, R.

2010-01-01

Patients with suspected tuberculosis without pulmonary lesions and with mediastinal lymphadenopathy often pose a diagnostic challenge. Endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) cytology is an established modality to evaluate mediastinal and abdominal lesions. The aim...

Alternative radiation-free registration technique for image-guided pedicle screw placement in deformed cervico-thoracic segments.

Science.gov (United States)

Kantelhardt, Sven R; Neulen, Axel; Keric, Naureen; Gutenberg, Angelika; Conrad, Jens; Giese, Alf

2017-10-01

Image-guided pedicle screw placement in the cervico-thoracic region is a commonly applied technique. In some patients with deformed cervico-thoracic segments, conventional or 3D fluoroscopy based registration of image-guidance might be difficult or impossible because of the anatomic/pathological conditions. Landmark based registration has been used as an alternative, mostly using separate registration of each vertebra. We here investigated a routine for landmark based registration of rigid spinal segments as single objects, using cranial image-guidance software. Landmark based registration of image-guidance was performed using cranial navigation software. After surgical exposure of the spinous processes, lamina and facet joints and fixation of a reference marker array, up to 26 predefined landmarks were acquired using a pointer. All pedicle screws were implanted using image guidance alone. Following image-guided screw placement all patients underwent postoperative CT scanning. Screw positions as well as intraoperative and clinical parameters were retrospectively analyzed. Thirteen patients received 73 pedicle screws at levels C6 to Th8. Registration of spinal segments, using the cranial image-guidance succeeded in all cases. Pedicle perforations were observed in 11.0%, severe perforations of >2 mm occurred in 5.4%. One patient developed a transient C8 syndrome and had to be revised for deviation of the C7 pedicle screw. No other pedicle screw-related complications were observed. In selected patients suffering from pathologies of the cervico-thoracic region, which impair intraoperative fluoroscopy or 3D C-arm imaging, landmark based registration of image-guidance using cranial software is a feasible, radiation-saving and a safe alternative.

SU-E-J-37: Feasibility of Utilizing Carbon Fiducials to Increase Localization Accuracy of Lumpectomy Cavity for Partial Breast Irradiation

International Nuclear Information System (INIS)

Zhang, Y; Hieken, T; Mutter, R; Park, S; Yan, E; Brinkmann, D; Pafundi, D

2015-01-01

Purpose To investigate the feasibility of utilizing carbon fiducials to increase localization accuracy of lumpectomy cavity for partial breast irradiation (PBI). Methods Carbon fiducials were placed intraoperatively in the lumpectomy cavity following resection of breast cancer in 11 patients. The patients were scheduled to receive whole breast irradiation (WBI) with a boost or 3D-conformal PBI. WBI patients were initially setup to skin tattoos using lasers, followed by orthogonal kV on-board-imaging (OBI) matching to bone per clinical practice. Cone beam CT (CBCT) was acquired weekly for offline review. For the boost component of WBI and PBI, patients were setup with lasers, followed by OBI matching to fiducials, with final alignment by CBCT matching to fiducials. Using carbon fiducials as a surrogate for the lumpectomy cavity and CBCT matching to fiducials as the gold standard, setup uncertainties to lasers, OBI bone, OBI fiducials, and CBCT breast were compared. Results Minimal imaging artifacts were introduced by fiducials on the planning CT and CBCT. The fiducials were sufficiently visible on OBI for online localization. The mean magnitude and standard deviation of setup errors were 8.4mm ± 5.3 mm (n=84), 7.3mm ± 3.7mm (n=87), 2.2mm ± 1.6mm (n=40) and 4.8mm ± 2.6mm (n=87), for lasers, OBI bone, OBI fiducials and CBCT breast tissue, respectively. Significant migration occurred in one of 39 implanted fiducials in a patient with a large postoperative seroma. Conclusion OBI carbon fiducial-based setup can improve localization accuracy with minimal imaging artifacts. With increased localization accuracy, setup uncertainties can be reduced from 8mm using OBI bone matching to 3mm using OBI fiducial matching for PBI treatment. This work demonstrates the feasibility of utilizing carbon fiducials to increase localization accuracy to the lumpectomy cavity for PBI. This may be particularly attractive for localization in the setting of proton therapy and other scenarios

SU-E-J-37: Feasibility of Utilizing Carbon Fiducials to Increase Localization Accuracy of Lumpectomy Cavity for Partial Breast Irradiation

Energy Technology Data Exchange (ETDEWEB)

Zhang, Y; Hieken, T; Mutter, R; Park, S; Yan, E; Brinkmann, D; Pafundi, D [Mayo Clinic, Rochester, MN (United States)

2015-06-15

Purpose To investigate the feasibility of utilizing carbon fiducials to increase localization accuracy of lumpectomy cavity for partial breast irradiation (PBI). Methods Carbon fiducials were placed intraoperatively in the lumpectomy cavity following resection of breast cancer in 11 patients. The patients were scheduled to receive whole breast irradiation (WBI) with a boost or 3D-conformal PBI. WBI patients were initially setup to skin tattoos using lasers, followed by orthogonal kV on-board-imaging (OBI) matching to bone per clinical practice. Cone beam CT (CBCT) was acquired weekly for offline review. For the boost component of WBI and PBI, patients were setup with lasers, followed by OBI matching to fiducials, with final alignment by CBCT matching to fiducials. Using carbon fiducials as a surrogate for the lumpectomy cavity and CBCT matching to fiducials as the gold standard, setup uncertainties to lasers, OBI bone, OBI fiducials, and CBCT breast were compared. Results Minimal imaging artifacts were introduced by fiducials on the planning CT and CBCT. The fiducials were sufficiently visible on OBI for online localization. The mean magnitude and standard deviation of setup errors were 8.4mm ± 5.3 mm (n=84), 7.3mm ± 3.7mm (n=87), 2.2mm ± 1.6mm (n=40) and 4.8mm ± 2.6mm (n=87), for lasers, OBI bone, OBI fiducials and CBCT breast tissue, respectively. Significant migration occurred in one of 39 implanted fiducials in a patient with a large postoperative seroma. Conclusion OBI carbon fiducial-based setup can improve localization accuracy with minimal imaging artifacts. With increased localization accuracy, setup uncertainties can be reduced from 8mm using OBI bone matching to 3mm using OBI fiducial matching for PBI treatment. This work demonstrates the feasibility of utilizing carbon fiducials to increase localization accuracy to the lumpectomy cavity for PBI. This may be particularly attractive for localization in the setting of proton therapy and other scenarios

Fluoroscopically guided placement of self-expandable metallic stents and stent-grafts in the treatment of acute malignant colorectal obstruction.

Science.gov (United States)

Kim, Honsoul; Kim, Seung Hyoung; Choi, Sun Young; Lee, Kwang-Hun; Won, Jong Yoon; Lee, Do Yun; Lee, Jong Tae

2008-12-01

To evaluate the technical feasibility and clinical effectiveness of fluoroscopically guided placement of self-expandable metallic stents and stent-grafts for acute malignant colorectal obstruction. Radiologic images and clinical reports of 42 patients (22 men, 20 women; age range, 28-93 years; median age, 65.5 years) who underwent fluoroscopically guided colorectal stent insertion without endoscopic assistance for acute malignant obstruction were reviewed retrospectively. Eighteen patients received bare stents as a bridge to surgery. Twenty-four patients received 27 insertions of either a bare stent (n = 15) or a stent-graft (n = 12) for palliation. The obstruction was located in the rectum (n = 8), sigmoid (n = 17), descending colon (n = 8), splenic flexure (n = 3), and transverse colon (n = 6). Clinical success, defined as more than 50% dilatation of the stent with subsequent symptomatic improvement, was achieved in 41 of the 42 patients (98%). No major procedure-related complications occurred. Minor complications occurred in eight of the 45 procedures (18%). No perioperative mortalities occurred within 1 month after surgery. In the palliative group, the median stent patency was 62 days (range, 0-1,014 days). There was no statistically significant difference in stent patency between the bare stents (range, 0-855 days; median, 68 days) and stent-grafts (range, 1-1,014 days; median, 81 days). Fluoroscopically guided placement of self-expandable metallic stents and stent-grafts for the relief of acute malignant colorectal obstruction was technically feasible without endoscopic assistance-even in lesions proximal to the splenic flexure and transverse colon-and clinically effective in both bridge to surgery and palliative management.

Sample positioning in neutron diffraction experiments using a multi-material fiducial marker

Energy Technology Data Exchange (ETDEWEB)

Marais, D., E-mail: Deon.Marais@necsa.co.za [Research and Development Division, South African Nuclear Energy Corporation (Necsa) SOC Limited, PO Box 582, Pretoria 0001 (South Africa); School of Mechanical and Nuclear Engineering, North-West University, Potchefstroom 2520 (South Africa); Venter, A.M., E-mail: Andrew.Venter@necsa.co.za [Research and Development Division, South African Nuclear Energy Corporation (Necsa) SOC Limited, PO Box 582, Pretoria 0001 (South Africa); Faculty of Agriculture Science and Technology, North-West University, Mahikeng 2790 (South Africa); Markgraaff, J., E-mail: Johan.Markgraaff@nwu.ac.za [School of Mechanical and Nuclear Engineering, North-West University, Potchefstroom 2520 (South Africa); James, J., E-mail: Jon.James@open.ac.uk [Faculty of Mathematics, Computing and Technology, The Open University, Milton Keynes, MK76AA England (United Kingdom)

2017-01-01

An alternative sample positioning method is reported for use in conjunction with sample positioning and experiment planning software systems deployed on some neutron diffraction strain scanners. In this approach, the spherical fiducial markers and location trackers used with optical metrology hardware are replaced with a specifically designed multi-material fiducial marker that requires one diffraction measurement. In a blind setting, the marker position can be determined within an accuracy of ±164 µm with respect to the instrument gauge volume. The scheme is based on a pre-determined relationship that links the diffracted peak intensity to the absolute positioning of the fiducial marker with respect to the instrument gauge volume. Two methods for establishing the linking relationship are presented, respectively based on fitting multi-dimensional quadratic functions and a cross-correlation artificial neural network.

The Utility of Endoscopic Ultrasound Guided Fine Needle Aspiration in the Diagnosis of Infectious Diseases—Report of Three Cases

Directory of Open Access Journals (Sweden)

Mauro Ajaj Saieg

2013-01-01

Full Text Available Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA is a fast and minimally invasive methodology with a crucial impact on patients’ management. It has an important and established role in the diagnosis and staging of mediastinal and abdominal malignancies, but little is discussed in the literature on the usefulness of this technique in the diagnosis of infectious diseases. In the current report, we present three different cases where EUS was essential for reaching the diagnosis of tuberculosis and paracoccidiodomicosis in cases otherwise seen as malignant. In conclusion, EUS was successful not only in obtaining enough cells for morphological analysis, but also for the production of cell blocks and assessment of the presence of the microorganisms by special stains. EUS allied to fine needle biopsy was an important tool in determining diagnoses of enlarged lymph nodes, revealing the diagnosis of infectious diseases in cases otherwise seen as malignant. The wide use of this methodology in cases such as those reported here cannot only rule out malignancy, but also aid critically ill patients by installing early proper therapy without the need for aggressive interventions.

Reliability of a CAD/CAM Surgical Guide for Implant Placement: An In Vitro Comparison of Surgeons' Experience Levels and Implant Sites.

Science.gov (United States)

Park, Su-Jung; Leesungbok, Richard; Cui, Taixing; Lee, Suk Won; Ahn, Su-Jin

This in vitro study evaluated the reliability of a surgical guide with regard to different levels of operator surgical experience and implant site. A stereolithographic surgical guide for epoxy resin mandibles with three edentulous molar sites was produced using a computer-aided design/computer-assisted manufacture (CAD/CAM) system. Two surgeons with and two surgeons without implant surgery experience placed implants in a model either using or not using the CAD/CAM surgical guide. Four groups were created: inexperienced surgeon without the guide (group 1); experienced surgeon without the guide (group 2); inexperienced surgeon with the guide (group 3); and experienced surgeon with the guide (group 4). Planned implants and placed implants were superimposed using digital software, and deviation parameters were calculated. There were no significant differences in any of the deviation parameters between the groups when using the surgical guide. With respect to the implant sites, there were no significant differences among the groups in any parameter. Use of the CAD/CAM surgical guide reduced discrepancies among operators performing implant surgery regardless of their level of experience. Whether or not the guide was used, differences in the anterior-posterior implant site in the molar area did not affect the accuracy of implant placement.

Robot-assisted 3D-TRUS guided prostate brachytherapy: System integration and validation

International Nuclear Information System (INIS)

Wei Zhouping; Wan Gang; Gardi, Lori; Mills, Gregory; Downey, Donal; Fenster, Aaron

2004-01-01

Current transperineal prostate brachytherapy uses transrectal ultrasound (TRUS) guidance and a template at a fixed position to guide needles along parallel trajectories. However, pubic arch interference (PAI) with the implant path obstructs part of the prostate from being targeted by the brachytherapy needles along parallel trajectories. To solve the PAI problem, some investigators have explored other insertion trajectories than parallel, i.e., oblique. However, parallel trajectory constraints in current brachytherapy procedure do not allow oblique insertion. In this paper, we describe a robot-assisted, three-dimensional (3D) TRUS guided approach to solve this problem. Our prototype consists of a commercial robot, and a 3D TRUS imaging system including an ultrasound machine, image acquisition apparatus and 3D TRUS image reconstruction, and display software. In our approach, we use the robot as a movable needle guide, i.e., the robot positions the needle before insertion, but the physician inserts the needle into the patient's prostate. In a later phase of our work, we will include robot insertion. By unifying the robot, ultrasound transducer, and the 3D TRUS image coordinate systems, the position of the template hole can be accurately related to 3D TRUS image coordinate system, allowing accurate and consistent insertion of the needle via the template hole into the targeted position in the prostate. The unification of the various coordinate systems includes two steps, i.e., 3D image calibration and robot calibration. Our testing of the system showed that the needle placement accuracy of the robot system at the 'patient's' skin position was 0.15 mm±0.06 mm, and the mean needle angulation error was 0.07 deg. . The fiducial localization error (FLE) in localizing the intersections of the nylon strings for image calibration was 0.13 mm, and the FLE in localizing the divots for robot calibration was 0.37 mm. The fiducial registration error for image calibration was 0

EFSUMB Guidelines on Interventional Ultrasound (INVUS), Part IV - EUS-guided interventions

DEFF Research Database (Denmark)

Jenssen, C; Hocke, M; Fusaroli, P

2016-01-01

The fourth part of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) Guidelines on Interventional Ultrasound describes general aspects of endoscopic ultrasound-guided diagnostic and therapeutic interventions and assesses the evidence for endoscopic ultrasound-gu...

Oral Rehabilitation of a Patient With Ectodermal Dysplasia Treated With Fresh-Frozen Bone Allografts and Computer-Guided Implant Placement: A Clinical Case Report.

Science.gov (United States)

Maiorana, Carlo; Poli, Pier Paolo; Poggio, Carlo; Barbieri, Paola; Beretta, Mario

2017-05-01

Ectodermal dysplasia (ED) is an inherited disorder characterized by abnormality of ectodermally derived structures. A recurrent oral finding is oligodontia, which in turn leads to a severely hypotrophic alveolar process with typical knife-edge morphology and adverse ridge contours. This unfavorable anatomy can seriously hamper proper implant placement. Fresh-frozen bone (FFB) allografts recently have been proposed to augment the residual bone volume for implant placement purposes; however, scientific evidence concerning the use of FFB to treat ED patients is absent. Similarly, data reporting computer-aided template-guided implant placement in medically compromised patients are limited. Thus the purpose of this report is to illustrate the oral rehabilitation of a female patient affected by ED and treated with appositional FFB block grafts and consecutive computer-guided flapless implant placement in a 2-stage procedure. Fixed implant-supported dental prostheses were finally delivered to the patient, which improved her self-esteem and quality of life. During the follow-up recall 1 year after the prosthetic loading, the clinical examination showed healthy peri-implant soft tissues with no signs of bleeding on probing or pathologic probing depths. The panoramic radiograph confirmed the clinical stability of the result. Peri-implant marginal bone levels were radiographically stable with neither pathologic bone loss at the mesial and distal aspects of each implant nor peri-implant radiolucency. Within the limitations of this report, the use of FFB allografts in association with computer-aided flapless implant surgery might be considered a useful technique in patients affected by ED. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Note: A simple image processing based fiducial auto-alignment method for sample registration.

Science.gov (United States)

Robertson, Wesley D; Porto, Lucas R; Ip, Candice J X; Nantel, Megan K T; Tellkamp, Friedjof; Lu, Yinfei; Miller, R J Dwayne

2015-08-01

A simple method for the location and auto-alignment of sample fiducials for sample registration using widely available MATLAB/LabVIEW software is demonstrated. The method is robust, easily implemented, and applicable to a wide variety of experiment types for improved reproducibility and increased setup speed. The software uses image processing to locate and measure the diameter and center point of circular fiducials for distance self-calibration and iterative alignment and can be used with most imaging systems. The method is demonstrated to be fast and reliable in locating and aligning sample fiducials, provided here by a nanofabricated array, with accuracy within the optical resolution of the imaging system. The software was further demonstrated to register, load, and sample the dynamically wetted array.

Objective assessment of the aesthetic outcomes of breast cancer treatment: toward automatic localization of fiducial points on digital photographs

Science.gov (United States)

Udpa, Nitin; Sampat, Mehul P.; Kim, Min Soon; Reece, Gregory P.; Markey, Mia K.

2007-03-01

The contemporary goals of breast cancer treatment are not limited to cure but include maximizing quality of life. All breast cancer treatment can adversely affect breast appearance. Developing objective, quantifiable methods to assess breast appearance is important to understand the impact of deformity on patient quality of life, guide selection of current treatments, and make rational treatment advances. A few measures of aesthetic properties such as symmetry have been developed. They are computed from the distances between manually identified fiducial points on digital photographs. However, this is time-consuming and subject to intra- and inter-observer variability. The purpose of this study is to investigate methods for automatic localization of fiducial points on anterior-posterior digital photographs taken to document the outcomes of breast reconstruction. Particular emphasis is placed on automatic localization of the nipple complex since the most widely used aesthetic measure, the Breast Retraction Assessment, quantifies the symmetry of nipple locations. The nipple complexes are automatically localized using normalized cross-correlation with a template bank of variants of Gaussian and Laplacian of Gaussian filters. A probability map of likely nipple locations determined from the image database is used to reduce the number of false positive detections from the matched filter operation. The accuracy of the nipple detection was evaluated relative to markings made by three human observers. The impact of using the fiducial point locations as identified by the automatic method, as opposed to the manual method, on the calculation of the Breast Retraction Assessment was also evaluated.

Stone extraction balloon-guided repeat self-expanding metal stent placement

Institute of Scientific and Technical Information of China (English)

Hyung; Hun; Kim; Jeong; Seop; Moon; Soo; Hyung; Ryu; Jung; Hwan; Lee; You; Sun; Kim

2010-01-01

Self-expanding metal stent (SEMS) placement offers safe and effective palliation in patients with upper gastrointestinal obstruction due to a malignancy. Well described complications of SEMS placement include tumor growth, obstruction, and stent migration. SEMS occlusions are treated by SEMS redeployment, argon plasma coagulation application, balloon dilation, and surgical bypass. At our center, we usually place the second SEMS into the first SEMS if there is complete occlusion by the tumor. We discovered a...

Diagnostic value of NobelGuide to minimize the need for reconstructive surgery of jaws before implant placement: a review.

Science.gov (United States)

Scotti, Roberto; Pellegrino, Gerardo; Marchetti, Claudio; Corinaldesi, Guiseppe; Ciocca, Leonardo

2010-01-01

To test if using a CAD/CAM system might reduce the necessity of bone augmentation in patients with atrophic maxillary arches before implant therapy. Twenty male and female patients consecutively scheduled for bone augmentation of the jaw before implant surgery were included in this study, with a total of 29 jaws (maxillary and mandibular) to analyze for the implant-supported fixed prosthesis group and 19 maxillary arches for the implant-supported removable prosthesis group. NobelGuide System (Nobel Biocare), Autocad System (Autodesk), and routine manual CT measurements of available bone were used in this study. The total results of the mean values of the fixed prosthesis group plus the mean values of the removable prosthesis group showed a statistically significant difference between the NobelGuide intervention score and both manual (P = .004) and Autocad (P = .001) measurements. The NobelGuide System represents a viable diagnostic device to reduce the entity or avoid bone reconstructive surgery before implant placements in the atrophic maxilla and mandible.

Multiple Diagnostic Imaging of a Patient with Solid Pseudopapillary Tumour of the Pancreas: EUS, CT and FDG PET/CT

International Nuclear Information System (INIS)

Chong, Ari; Ha, Jungmin; Kwon, Seong Young

2014-01-01

Solid pseudopapillary neoplam of the pancreas (SPNP) is a rare tumour, making up approximately 1 % to 3 % of pancreatic tumours. About 90 % of SPNPs occur in young women (mean age 35 years). SPNP rarely causes symptoms and is usually detected incidentally. Differentiating SPNP from other pancreatic tumours is very important, because surgical resection may provide favourable outcomes. Metastases or invasion to other organs has been reported in 15% to 20% of patients with SPNP. Histologically, the uniform, bland-appearing, epithelial cells of SPNP are similar to the cells making up other pancreatic endocrine neoplasms. However, SPNP cannot be regarded as a pure pancreatic endocrine neoplasm because of the absence of chromogranin A expression and low expression of other endocrine markers. SPNP has not been associated with specific serum tumour markers. CT and MRI are used for the diagnosis and staging of SPNP. On contrast-enhanced CT, SPNP shows isoattenuation on precontrast CT, weak enhancement during the arterial phase and gradually increased enhancement during the portal venous phase. SPNP can appear as an encapsulated lesion with cystic degeneration, necrosis, haemorrhage or calcification. MRI can characterise internal signal intensities, including a blood component, which is helpful in making a differential diagnosis. Dong et al. analysed CT and MRI findings from eight patients with SPNP and reported that four lesions showed mixed solid and cystic components, and the others appeared almost completely solid. Stoita et al. reported that EUS-guided fine-needle aspiration was a minimally invasive, safe and reliable diagnostic method for SPNP. They reported that all seven lesions examined were hypoechoic, heterogeneous and well circumscribed. Their findings are very similar to the findings in our patient. In addition, it is clear from the EUS images of our patient that EUS provides better images for evaluating SPNP lesions than US of the pancreas (Figs. 1e and f and 2

Relationship of pancreatic mass size and diagnostic yield of endoscopic ultrasound-guided fine needle aspiration.

Science.gov (United States)

Siddiqui, Ali A; Brown, Lauren J; Hong, Shih-Kuang S; Draganova-Tacheva, Rossitza A; Korenblit, Jason; Loren, David E; Kowalski, Thomas E; Solomides, Charalambos

2011-11-01

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is central to discerning the diagnosis of solid pancreatic tumors through tissue acquisition. Test performance is affected by a number of factors including location of mass within the pancreas, presence of onsite cytology technologist, and number of passes with the needle. The influence of tumor size has not been well studied. The objective of the current study was to determine whether the size of mass affects the diagnostic accuracy for solid pancreatic lesions aspirated under EUS guidance. Data were collected retrospectively on all patients with solid pancreatic masses undergoing EUS-FNA from June 2003 to August 2010. The cytology samples were reported as positive, suspicious for malignancy, atypical, negative, or nondiagnostic. The gold standard for a cytological diagnosis was histological confirmation or clinical follow-up of more than 6 months with repeat imaging. Patients were divided into five groups based upon lesion size as follows: (a) less than 1 cm, (b) 1-2 cm, (c) 2-3 cm, (d) 3-4 cm, and (e) greater than 4 cm. Performance characteristics of EUS-FNA including sensitivity, specificity, and accuracy were compared for each group. Accuracy was defined as the ratio of the sum of true-positive and true-negative values divided by the number of lesions. We identified 583 patients with solid pancreatic lesions in which EUS-FNA was performed and adequate cellularity was obtained (47% men, mean age 65 ± 1.4 (SE) years). Overall, 486 (83%) of lesions were pancreatic adenocarcinoma, 18 (3%) were neuroendocrine tumors, 12 (2%) were lymphomas, and 67 (12%) were benign lesions. The median size of the mass was 3 cm (range, 0.5-7 cm). A mean of 4.9 passes (range, 1-9 passes) was needed to obtain adequate samples from lesions. The overall yield of obtaining adequate samples for diagnosis was 85%. When stratified by size, the EUS-FNA sensitivity for lesions with size 4 cm was 40, 75.9, 86.9, 93

Lung tumor tracking during stereotactic radiotherapy treatment with the CyberKnife: Marker placement and early results

International Nuclear Information System (INIS)

Nuyttens, J.J.; Prevost, J.B.; Praag, J.; Hoogeman, M.; Levendag, P.C.; Klaveren, R.J. van; Pattynama, P.M.T.

2006-01-01

Lung tumor tracking during stereotactic radiotherapy with the CyberKnife requires the insertion of markers in or close to the tumor. To reduce the risk of pneumothorax, three methods of marker placement were used: 1) intravascular coil placement, 2) percutaneous intrathoracal, and 3) percutaneous extrathoracal placement. We investigated the toxicity of marker placement and the tumor response of the lung tumor tracking treatment. Markers were placed in 20 patients with 22 tumors: 13 patients received a curative treatment, seven a palliative. The median Charlson Comorbidity Score was 4 (range: 1-8). Platinum fiducials and intravascular embolisation coils were used as markers. In total, 78 markers were placed: 34 intrathoracal, 23 intravascular and 21 extrathoracal. The PTV equaled the GTV + 5 mm. A median dose of 45 Gy (range: 30-60 Gy, in 3 fractions) was prescribed to the 70-85% isodose. The response was evaluated with a CTscan performed 6-8 weeks after the last treatment and routinely thereafter. The median follow-up was 4 months (range: 2-11). No severe toxicity due to the marker placement was seen. Pneumothorax was not seen. The local control was 100%. Four tumors in four patients showed a complete response, 15 tumors in 14 patients a partial response, and three tumors in two patients with metastatic disease had stable disease. No severe toxicity of marker placement was seen due to the appropriate choice of one of the three methods. CyberKnife tumor tracking with markers is feasible and resulted in excellent tumor response. Longer follow-up is needed to validate the local control

Surgical fiducial segmentation and tracking for pose estimation based on ultrasound B-mode images.

Science.gov (United States)

Lei Chen; Kuo, Nathanael; Aalamifar, Fereshteh; Narrow, David; Coon, Devin; Prince, Jerry; Boctor, Emad M

2016-08-01

Doppler ultrasound is a non-invasive diagnostic tool for the quantitative measurement of blood flow. However, given that it provides velocity data that is dependent on the location and angle of measurement, repeat measurements to detect problems over time may require an expert to return to the same location. We therefore developed an image-guidance system based on ultrasound B-mode images that enables an inexperienced user to position the ultrasound probe at the same site repeatedly in order to acquire a comparable time series of Doppler readings. The system utilizes a bioresorbable fiducial and complementing software composed of the fiducial detection, key points tracking, probe pose estimation, and graphical user interface (GUI) modules. The fiducial is an echogenic marker that is implanted at the surgical site and can be detected and tracked during ultrasound B-mode screening. The key points on the marker can next be used to determine the pose of the ultrasound probe with respect to the marker. The 3D representation of the probe with its position and orientation are then displayed in the GUI for the user guidance. The fiducial detection has been tested on the data sets collected from three animal studies. The pose estimation algorithm was validated by five data sets collected by a UR5 robot. We tested the system on a plastisol phantom and showed that it can detect and track the fiducial marker while displaying the probe pose in real-time.

Development and clinical evaluation of automatic fiducial detection for tumor tracking in cine megavoltage images during volumetric modulated arc therapy

International Nuclear Information System (INIS)

Azcona, Juan Diego; Li Ruijiang; Mok, Edward; Hancock, Steven; Xing Lei

2013-01-01

Purpose: Real-time tracking of implanted fiducials in cine megavoltage (MV) imaging during volumetric modulated arc therapy (VMAT) delivery is complicated due to the inherent low contrast of MV images and potential blockage of dynamic leaves configurations. The purpose of this work is to develop a clinically practical autodetection algorithm for motion management during VMAT. Methods: The expected field-specific segments and the planned fiducial position from the Eclipse (Varian Medical Systems, Palo Alto, CA) treatment planning system were projected onto the MV images. The fiducials were enhanced by applying a Laplacian of Gaussian filter in the spatial domain for each image, with a blob-shaped object as the impulse response. The search of implanted fiducials was then performed on a region of interest centered on the projection of the fiducial when it was within an open field including the case when it was close to the field edge or partially occluded by the leaves. A universal template formula was proposed for template matching and normalized cross correlation was employed for its simplicity and computational efficiency. The search region for every image was adaptively updated through a prediction model that employed the 3D position of the fiducial estimated from the localized positions in previous images. This prediction model allowed the actual fiducial position to be tracked dynamically and was used to initialize the search region. The artifacts caused by electronic interference during the acquisition were effectively removed. A score map was computed by combining both morphological information and image intensity. The pixel location with the highest score was selected as the detected fiducial position. The sets of cine MV images taken during treatment were analyzed with in-house developed software written in MATLAB (The Mathworks, Inc., Natick, MA). Five prostate patients were analyzed to assess the algorithm performance by measuring their positioning

SU-F-P-30: Clinical Assessment of Auto Beam-Hold Triggered by Fiducial Localization During Prostate RapidArc Delivery

Energy Technology Data Exchange (ETDEWEB)

Atkinson, P; Chen, Q [Flower Hospital, Sylvania, OH (United States)

2016-06-15

Purpose: To assess the clinical efficacy of auto beam hold during prostate RapidArc delivery, triggered by fiducial localization on kV imaging with a Varian True Beam. Methods: Prostate patients with four gold fiducials were candidates in this study. Daily setup was accomplished by aligning to fiducials using orthogonal kV imaging. During RapidArc delivery, a kV image was automatically acquired with a momentary beam hold every 60 degrees of gantry rotation. The position of each fiducial was identified by a search algorithm and compared to a predetermined 1.4 cm diameter target area. Treatment continued if all the fiducials were within the target area. If any fiducial was outside the target area the beam hold was not released, and the operators determined if the patient needed re-alignment using the daily setup method. Results: Four patients were initially selected. For three patients, the auto beam hold performed seamlessly. In one instance, the system correctly identified misaligned fiducials, stopped treatment, and the patient was re-positioned. The fourth patient had a prosthetic hip which sometimes blocked the fiducials and caused the fiducial search algorithm to fail. The auto beam hold was disabled for this patient and the therapists manually monitored the fiducial positions during treatment. Average delivery time for a 2-arc fraction was increased by 59 seconds. Phantom studies indicated the dose discrepancy related to multiple beam holds is <0.1%. For a plan with 43 fractions, the additional imaging increased dose by an estimated 68 cGy. Conclusion: Automated intrafraction kV imaging can effectively perform auto beam holds due to patient movement, with the exception of prosthetic hip patients. The additional imaging dose and delivery time are clinically acceptable. It may be a cost-effective alternative to Calypso in RapidArc prostate patient delivery. Further study is warranted to explore its feasibility under various clinical conditions.

SU-F-P-30: Clinical Assessment of Auto Beam-Hold Triggered by Fiducial Localization During Prostate RapidArc Delivery

International Nuclear Information System (INIS)

Atkinson, P; Chen, Q

2016-01-01

Purpose: To assess the clinical efficacy of auto beam hold during prostate RapidArc delivery, triggered by fiducial localization on kV imaging with a Varian True Beam. Methods: Prostate patients with four gold fiducials were candidates in this study. Daily setup was accomplished by aligning to fiducials using orthogonal kV imaging. During RapidArc delivery, a kV image was automatically acquired with a momentary beam hold every 60 degrees of gantry rotation. The position of each fiducial was identified by a search algorithm and compared to a predetermined 1.4 cm diameter target area. Treatment continued if all the fiducials were within the target area. If any fiducial was outside the target area the beam hold was not released, and the operators determined if the patient needed re-alignment using the daily setup method. Results: Four patients were initially selected. For three patients, the auto beam hold performed seamlessly. In one instance, the system correctly identified misaligned fiducials, stopped treatment, and the patient was re-positioned. The fourth patient had a prosthetic hip which sometimes blocked the fiducials and caused the fiducial search algorithm to fail. The auto beam hold was disabled for this patient and the therapists manually monitored the fiducial positions during treatment. Average delivery time for a 2-arc fraction was increased by 59 seconds. Phantom studies indicated the dose discrepancy related to multiple beam holds is <0.1%. For a plan with 43 fractions, the additional imaging increased dose by an estimated 68 cGy. Conclusion: Automated intrafraction kV imaging can effectively perform auto beam holds due to patient movement, with the exception of prosthetic hip patients. The additional imaging dose and delivery time are clinically acceptable. It may be a cost-effective alternative to Calypso in RapidArc prostate patient delivery. Further study is warranted to explore its feasibility under various clinical conditions.

Preoperative short hookwire placement for small pulmonary lesions: evaluation of technical success and risk factors for initial placement failure.

Science.gov (United States)

Iguchi, Toshihiro; Hiraki, Takao; Matsui, Yusuke; Fujiwara, Hiroyasu; Masaoka, Yoshihisa; Tanaka, Takashi; Sato, Takuya; Gobara, Hideo; Toyooka, Shinichi; Kanazawa, Susumu

2018-05-01

To retrospectively evaluate the technical success of computed tomography fluoroscopy-guided short hookwire placement before video-assisted thoracoscopic surgery and to identify the risk factors for initial placement failure. In total, 401 short hookwire placements for 401 lesions (mean diameter 9.3 mm) were reviewed. Technical success was defined as correct positioning of the hookwire. Possible risk factors for initial placement failure (i.e., requirement for placement of an additional hookwire or to abort the attempt) were evaluated using logistic regression analysis for all procedures, and for procedures performed via the conventional route separately. Of the 401 initial placements, 383 were successful and 18 failed. Short hookwires were finally placed for 399 of 401 lesions (99.5%). Univariate logistic regression analyses revealed that in all 401 procedures only the transfissural approach was a significant independent predictor of initial placement failure (odds ratio, OR, 15.326; 95% confidence interval, CI, 5.429-43.267; p < 0.001) and for the 374 procedures performed via the conventional route only lesion size was a significant independent predictor of failure (OR 0.793, 95% CI 0.631-0.996; p = 0.046). The technical success of preoperative short hookwire placement was extremely high. The transfissural approach was a predictor initial placement failure for all procedures and small lesion size was a predictor of initial placement failure for procedures performed via the conventional route. • Technical success of preoperative short hookwire placement was extremely high. • The transfissural approach was a significant independent predictor of initial placement failure for all procedures. • Small lesion size was a significant independent predictor of initial placement failure for procedures performed via the conventional route.

Comparison between radiation exposure levels using an image intensifier and a flat-panel detector-based system in image-guided central venous catheter placement in children weighing less than 10 kg

Energy Technology Data Exchange (ETDEWEB)

Miraglia, Roberto; Maruzzelli, Luigi; Cortis, Kelvin; Gerasia, Roberta; Maggio, Simona; Luca, Angelo [Diagnostic and Therapeutic Services, Mediterranean Institute for Transplantation and Advanced Specialized Therapies (ISMETT), Palermo (Italy); Piazza, Marcello [Department of Anesthesia, Mediterranean Institute for Transplantation and Advanced Specialized Therapies (ISMETT), Palermo (Italy); Tuzzolino, Fabio [Department of Information Technology, Mediterranean Institute for Transplantation and Advanced Specialized Therapies (ISMETT), Palermo (Italy)

2014-09-10

Ultrasound-guided central venous puncture and fluoroscopic guidance during central venous catheter (CVC) positioning optimizes technical success and lowers the complication rates in children, and is therefore considered standard practice. The purpose of this study was to compare the radiation exposure levels recorded during CVC placement in children weighing less than 10 kg in procedures performed using an image intensifier-based angiographic system (IIDS) to those performed in a flat-panel detector-based interventional suite (FPDS). A retrospective review of 96 image-guided CVC placements, between January 2008 and October 2013, in 49 children weighing less than 10 kg was performed. Mean age was 8.2 ± 4.4 months (range: 1-22 months). Mean weight was 7.1 ± 2.7 kg (range: 2.5-9.8 kg). The procedures were classified into two categories: non-tunneled and tunneled CVC placement. Thirty-five procedures were performed with the IIDS (21 non-tunneled CVC, 14 tunneled CVC); 61 procedures were performed with the FPDS (47 non-tunneled CVC, 14 tunneled CVC). For non-tunneled CVC, mean DAP was 113.5 ± 126.7 cGy cm{sup 2} with the IIDS and 15.9 ± 44.6 cGy . cm{sup 2} with the FPDS (P < 0.001). For tunneled CVC, mean DAP was 84.6 ± 81.2 cGy . cm{sup 2} with the IIDS and 37.1 ± 33.5 cGy cm{sup 2} with the FPDS (P = 0.02). The use of flat-panel angiographic equipment reduces radiation exposure in small children undergoing image-guided CVC placement. (orig.)

Usefulness of combined percutaneous-endoscopic rendezvous techniques after failed therapeutic endoscopic retrograde cholangiography in the era of endoscopic ultrasound guided rendezvous.

Science.gov (United States)

Yang, Min Jae; Kim, Jin Hong; Hwang, Jae Chul; Yoo, Byung Moo; Kim, Soon Sun; Lim, Sun Gyo; Won, Je Hwan

2017-12-01

The rendezvous approach is a salvage technique after failure of endoscopic retrograde cholangiography (ERC). In certain circumstances, percutaneous-endoscopic rendezvous (PE-RV) is preferred, and endoscopic ultrasound-guided rendezvous (EUS-RV) is difficult to perform. We aimed to evaluate PE-RV outcomes, describe the PE-RV techniques, and identify potential indications for PE-RV over EUS-RV.Retrospective analysis was conducted of a prospectively designed ERC database between January 2005 and December 2016 at a tertiary referral center including cases where PE-RV was used as a salvage procedure after ERC failure.During the study period, PE-RV was performed in 42 cases after failed therapeutic ERC; 15 had a surgically altered enteric anatomy. The technical success rate of PE-RV was 92.9% (39/42), with a therapeutic success rate of 88.1% (37/42). Potential indications for PE-RV over EUS-RV were identified in 23 cases, and either PE-RV or EUS-RV could have effectively been used in 19 cases. Endoscopic bile duct access was successfully achieved with PE-RV in 39 cases with accessible biliary orifice using one of PE-RV cannulation techniques (classic, n = 11; parallel, n = 19; and adjunctive maneuvers, n = 9).PE-RV uses a unique technology and has clinical indications that distinguish it from EUS-RV. Therefore, PE-RV can still be considered a useful salvage technique for the treatment of biliary obstruction after ERC failure.

A comparative study of two techniques (electrocardiogram- and landmark-guided for correct depth of the central venous catheter placement in paediatric patients undergoing elective cardiovascular surgery

Directory of Open Access Journals (Sweden)

Neeraj Kumar Barnwal

2016-01-01

Full Text Available Background and Aims: The complications of central venous catheterisation can be minimized by ensuring catheter tip placement just above the superior vena cava-right atrium junction. We aimed to compare two methods, using an electrocardiogram (ECG or landmark as guides, for assessing correct depth of central venous catheter (CVC placement. Methods: In a prospective randomised study of sixty patients of <12 years of age, thirty patients each were allotted randomly to two groups (ECG and landmark. After induction, central venous catheterisation was performed by either of the two techniques and position of CVC tip was compared in post-operative chest X-ray with respect to carina. Unpaired t-test was used for quantitative data and Chi-square test was used for qualitative data. Results: In ECG group, positions of CVC tip were above carina in 12, at carina in 9 and below carina in 9 patients. In landmark group, the positions of CVC tips were above carina in 10, at carina in 4 and below carina in 16 patients. Mean distance of CVC tip in ECG group was 0.34 ± 0.23 cm and 0.66 ± 0.35 cm in landmark group (P = 0.0001. Complications occurred in one patient in ECG group and in nine patients in landmark group (P = 0.0056. Conclusion: Overall, landmark-guided technique was comparable with ECG technique. ECG-guided technique was more precise for CVC tip placement closer to carina. The incidence of complications was more in the landmark group.

Minimal guided bone regeneration procedure for immediate implant placement in the esthetic zone

Directory of Open Access Journals (Sweden)

Nettemu Sunil Kumar

2013-01-01

Full Text Available The anterior maxilla presents a challenging milieu interior for ideal placement of implants because of the compromised bone quality. With the advent of intraoral bone harvesting and augmentation techniques, immediate implant placement into fresh extraction sockets have become more predictable. Immediate implant placement has numerous advantages compared to the delayed procedure including superior esthetic and functional outcomes, maintenance of soft and hard tissue integrity and increased patient compliance. This case report exhibits immediate implant placement in the maxillary esthetic zone by combining a minimal invasive autogenous block bone graft harvest technique for ensuring successful osseointegration of the implant at the extraction site.

US-guided placement of temporary internal jugular vein catheters: immediate technical success and complications in normal and high-risk patients

International Nuclear Information System (INIS)

Oguzkurt, Levent; Tercan, Fahri; Kara, Gulcan; Torun, Dilek; Kizilkilic, Osman; Yildirim, Tulin

2005-01-01

Objective: : To evaluate the technical success and immediate complication rates of temporary internal jugular vein (IJV) haemodialysis catheter placement in normal and high-risk patients. Methods and materials: Two-hundred and twenty temporary internal jugular vein catheters inserted under ultrasound guidance in 172 patients were prospectively analyzed. Of 172 patients, 93 (54%) were males and 79 (46%) were females (age range, 18-83; mean, 56.0 years). Of 220 catheters, 171 (78%) were placed in patients who had a risk factor for catheter placement like patients with disorder of haemostasis, poor compliance, and previous multiple catheter insertion in the same IJV. Forty-seven (21.3%) procedures were performed on bed-side. A catheter was inserted in the right IJV in 178 procedures (80.9%) and left IJV in 42 procedures. Of 172 patients, 112 (65%) had only one catheter placement and the rest had had more than one catheter placement (range, 1-5). Results: Technical success was achieved in all patients (100%). Average number of puncture was 1.24 (range, 1-3). One hundred and eighty-three insertions (83.1%) were single-wall punctures, whereas 37 punctures were double wall punctures. Nine (4%) minor complications were encountered. Inadvertent carotid artery puncture without a sequel in four procedures (1.8%), oozing of blood around the catheter in three procedures (1.4%), a small hematoma in one procedure (0.4%), and puncture through the pleura in one procedure (0.4%) without development of pneumothorax. Oozing of blood was seen only in patients with disorder of haemostasis. Conclusion: Ultrasound-guided placement of internal jugular vein catheters is very safe with very high success rate and few complications. It can safely be performed in high-risk patients, like patients with disorders of haemostasis and patients with previous multiple catheter insertion in the same vein

Geometry planning and image registration in magnetic particle imaging using bimodal fiducial markers

International Nuclear Information System (INIS)

Werner, F.; Hofmann, M.; Them, K.; Knopp, T.; Jung, C.; Salamon, J.; Kaul, M. G.; Mummert, T.; Adam, G.; Ittrich, H.; Werner, R.; Säring, D.; Weber, O. M.

2016-01-01

Purpose: Magnetic particle imaging (MPI) is a quantitative imaging modality that allows the distribution of superparamagnetic nanoparticles to be visualized. Compared to other imaging techniques like x-ray radiography, computed tomography (CT), and magnetic resonance imaging (MRI), MPI only provides a signal from the administered tracer, but no additional morphological information, which complicates geometry planning and the interpretation of MP images. The purpose of the authors’ study was to develop bimodal fiducial markers that can be visualized by MPI and MRI in order to create MP–MR fusion images. Methods: A certain arrangement of three bimodal fiducial markers was developed and used in a combined MRI/MPI phantom and also during in vivo experiments in order to investigate its suitability for geometry planning and image fusion. An algorithm for automated marker extraction in both MR and MP images and rigid registration was established. Results: The developed bimodal fiducial markers can be visualized by MRI and MPI and allow for geometry planning as well as automated registration and fusion of MR–MP images. Conclusions: To date, exact positioning of the object to be imaged within the field of view (FOV) and the assignment of reconstructed MPI signals to corresponding morphological regions has been difficult. The developed bimodal fiducial markers and the automated image registration algorithm help to overcome these difficulties.

Geometry planning and image registration in magnetic particle imaging using bimodal fiducial markers

Energy Technology Data Exchange (ETDEWEB)

Werner, F., E-mail: f.werner@uke.de; Hofmann, M.; Them, K.; Knopp, T. [Section for Biomedical Imaging, University Medical Center Hamburg-Eppendorf, Hamburg 20246, Germany and Institute for Biomedical Imaging, Hamburg University of Technology, Hamburg 21073 (Germany); Jung, C.; Salamon, J.; Kaul, M. G.; Mummert, T.; Adam, G.; Ittrich, H. [Department of Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, Hamburg 20246 (Germany); Werner, R.; Säring, D. [Institute for Computational Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg 20246 (Germany); Weber, O. M. [Philips Medical Systems DMC GmbH, Hamburg 22335 (Germany)

2016-06-15

Purpose: Magnetic particle imaging (MPI) is a quantitative imaging modality that allows the distribution of superparamagnetic nanoparticles to be visualized. Compared to other imaging techniques like x-ray radiography, computed tomography (CT), and magnetic resonance imaging (MRI), MPI only provides a signal from the administered tracer, but no additional morphological information, which complicates geometry planning and the interpretation of MP images. The purpose of the authors’ study was to develop bimodal fiducial markers that can be visualized by MPI and MRI in order to create MP–MR fusion images. Methods: A certain arrangement of three bimodal fiducial markers was developed and used in a combined MRI/MPI phantom and also during in vivo experiments in order to investigate its suitability for geometry planning and image fusion. An algorithm for automated marker extraction in both MR and MP images and rigid registration was established. Results: The developed bimodal fiducial markers can be visualized by MRI and MPI and allow for geometry planning as well as automated registration and fusion of MR–MP images. Conclusions: To date, exact positioning of the object to be imaged within the field of view (FOV) and the assignment of reconstructed MPI signals to corresponding morphological regions has been difficult. The developed bimodal fiducial markers and the automated image registration algorithm help to overcome these difficulties.

A linear programming approach for placement of applicants to academic programs.

Science.gov (United States)

Kassa, Biniyam Asmare

2013-01-01

This paper reports a linear programming approach for placement of applicants to study programs developed and implemented at the college of Business & Economics, Bahir Dar University, Bahir Dar, Ethiopia. The approach is estimated to significantly streamline the placement decision process at the college by reducing required man hour as well as the time it takes to announce placement decisions. Compared to the previous manual system where only one or two placement criteria were considered, the new approach allows the college's management to easily incorporate additional placement criteria, if needed. Comparison of our approach against manually constructed placement decisions based on actual data for the 2012/13 academic year suggested that about 93 percent of the placements from our model concur with the actual placement decisions. For the remaining 7 percent of placements, however, the actual placements made by the manual system display inconsistencies of decisions judged against the very criteria intended to guide placement decisions by the college's program management office. Overall, the new approach proves to be a significant improvement over the manual system in terms of efficiency of the placement process and the quality of placement decisions.

USES 2.0, The Uniform System for the Evaluation of Substances, version 2.0 ; supplement to EUSES

NARCIS (Netherlands)

Linders JBHJ; Jager DT (eds.); CSR; ECO

1997-01-01

Dit interimrapport beschrijft het risicobeoordelingssysteem voor landbouw- en niet-landbouwbestrijdingsmiddelen. Het zal worden geintegreerd met het European Union System for the Evaluation of Substances, EUSES 1.0, tot USES 2.0, de tweede versie van het Uniforme Beoordelingssysteem voor

Assessment of fiducial markers to enable the co-registration of photographs and MRI data.

Science.gov (United States)

Webb, Bridgette A; Petrovic, Andreas; Urschler, Martin; Scheurer, Eva

2015-03-01

To investigate the visualisation of novel external fiducial skin markers in photography and MRI. To co-register photographs and MR images, and additionally assess the spatial accuracy of these co-registrations with the view of future application in the investigation of forensically relevant soft tissue lesions. Strand-shaped fiducial markers were secured externally over hematomas on the thigh of 10 volunteers. The region of interest was photographed and examined using MRI at 3T in oblique and transversal orientations and the visibility of the markers assessed. Markers provided 'control points' in both sets of images, enabling the computation of an affine transform to register oblique MR images to photographs. The fiducial registration error was evaluated by calculating the root-mean-square error of nine corresponding evaluation points visible in both modalities. Fiducial markers were clearly visualised in both photography and MRI. The co-registration of photographs and oblique MR images was achieved for all participants. The overall root-mean-square error for registrations was 1.18mm (TIRM) and 1.46mm (TSE2D with SPAIR fat-suppression). The proposed approach led to the successful visualisation of non-invasive fiducial markers using photography and MRI (TIRM and TSE2D (SPAIR) sequences). This visualisation, combined with an affine transformation process provided a simple, cost-effective way to accurately co-register photographs and MR images of subcutaneous hematomas located on the thigh. Further investigation of the novel markers and the proposed co-visualisation approach holds potential to improve not only the forensic documentation of soft tissue lesions, but to also improve certain clinical applications, including the area of dermatology. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Percutaneous placement of ureteral stent

Energy Technology Data Exchange (ETDEWEB)

Kim, Seung Hyup; Park, Jae Hyung; Han, Joon Koo; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

1990-12-15

Antegrade placement of ureteral stents has successfully achieved in 41 of 46 ureters. When it was difficult to advance ureteral stents through the lesion, it was facilitated by retrograde guide-wire snare technique through urethra. Complications associated with the procedure were non-function of ureteral stent by occlusion, upward migration,and spontaneous fracture of ureteral stent. These complications were managed by percutaneous nephrostomy and removal of ureteral stents by guide-wire snare technique and insertion of a new ureteral stent. While blood cell in urine was markedly increased in about 50% of patients following the procedure.

Robust fluoroscopic tracking of fiducial markers: exploiting the spatial constraints

International Nuclear Information System (INIS)

Li Rui; Sharp, Gregory

2013-01-01

Two new fluoroscopic fiducial tracking methods that exploit the spatial relationship among the multiple implanted fiducial to achieve fast, accurate and robust tracking are proposed in this paper. The spatial relationship between multiple implanted markers are modeled as Gaussian distributions of their pairwise distances over time. The means and standard deviations of these distances are learned from training sequences, and pairwise distances that deviate from these learned distributions are assigned a low spatial matching score. The spatial constraints are incorporated in two different algorithms: a stochastic tracking method and a detection based method. In the stochastic method, hypotheses of the ‘true’ fiducial position are sampled from a pre-trained respiration motion model. Each hypothesis is assigned an importance value based on image matching score and spatial matching score. Learning the parameters of the motion model is needed in addition to learning the distribution parameters of the pairwise distances in the proposed stochastic tracking approach. In the detection based method, a set of possible marker locations are identified by using a template matching based fiducial detector. The best location is obtained by optimizing the image matching score and spatial matching score through non-serial dynamic programming. In this detection based approach, there is no need to learn the respiration motion model. The two proposed algorithms are compared with a recent work using a multiple hypothesis tracking (MHT) algorithm which is denoted by MHT, Tang et al (2007 Phys. Med. Biol. 52 4081–98). Phantom experiments were performed using fluoroscopic videos captured with known motion relative to an anthropomorphic phantom. The patient experiments were performed using a retrospective study of 16 fluoroscopic videos of liver cancer patients with implanted fiducials. For the motion phantom data sets, the detection based approach has the smallest tracking error (�

BioXmark for high-precision radiotherapy in an orthotopic pancreatic tumor mouse model. Experiences with a liquid fiducial marker

International Nuclear Information System (INIS)

Dobiasch, S.; Kampfer, S.; Burkhardt, R.; Wilkens, J.J.; Schilling, D.; Schmid, T.E.; Combs, S.E.

2017-01-01

High-precision radiotherapy (RT) requires precise positioning, particularly with high single doses. Fiducial markers in combination with onboard imaging are excellent tools to support this. The purpose of this study is to establish a pancreatic cancer mouse model for high-precision image-guided RT (IGRT) using the liquid fiducial marker BioXmark (Nanovi, Kongens Lyngby, Denmark). In an animal-based cancer model, different volumes of BioXmark (10-50 μl), application forms, and imaging modalities - cone-beam computer tomography (CBCT) incorporated in either the Small Animal Radiation Research Platform (SARRP) or the small-animal micro-CT Scanner (SkyScan; Bruker, Brussels, Belgium) - as well as subsequent RT with the SARRP system were analyzed to derive recommendations for BioXmark. Even small volumes (10 μl) of BioXmark could be detected by CBCT (SARRP and Skyscan). Larger volumes (50 μl) led to hardening artefacts. The position of BioXmark was monitored at least weekly by CBCT and was stable over 4 months. BioXmark was shown to be well tolerated; no changes in physical condition or toxic side effects were observed in comparison to control mice. BioXmark enabled an exact fusion with the original treatment plan with less hardening artefacts, and minimized the application of contrast agent for fractionated RT. An orthotopic pancreatic tumor mouse model was established for high-precision IGRT using a fiducial marker. BioXmark was successfully tested and provides the perfect basis for improved imaging in high-precision RT. BioXmark enables a unique application method and optimal targeted precision in fractionated RT. Therefore, preclinical trials evaluating novel fractionation regimens and/or combination treatment with high-end RT can be performed. (orig.) [de

Behandling af insulinom med alkoholsklerosering

DEFF Research Database (Denmark)

Schnack, Christina; Christensen, Carina Ørts; Beck-Nielsen, Henning

2012-01-01

The efficacy and safety of endoscopic ultrasound (EUS)-guided alcohol ablation of an insulinoma in a patient not candidate for surgery is being evaluated. A 89 year-old male patient with insulinoma and serious cardiac disease was treated with EUS-guided alcohol ablation. The only complication...... was a slight degree of pancreatitis. Two months after the ablation values of plasma glucose and serum pro-insulin were normalized. EUS-guided alcohol ablation is a safe and efficient alternative to surgical resection of insulinomas in poor surgical candidates....

Technique of Peritoneal Catheter Placement under Fluoroscopic Guidance

International Nuclear Information System (INIS)

Abdel-Aal, A.K.; Gaddikeri, S.; Saddekni, S.

2011-01-01

Peritoneal catheters are mainly used for peritoneal dialysis in patients with end-stage renal disease. Other uses of this catheter include intraperitoneal chemotherapy and gene therapy for ovarian cancer and draining of uncontrolled refractory ascites in patients with liver cirrhosis. Traditionally, surgeons place most of these peritoneal catheters either by laparoscopy or open laparotomy. We detail our percutaneous approach to placing peritoneal catheters using fluoroscopic guidance. We emphasize the use of additional ultrasound guidance, including gray scale and color Doppler ultrasound, to determine the safest puncture site and to guide the initial needle puncture in order to avoid bowel perforation and injury to epigastric artery. We present our experience in placing peritoneal catheters using this technique in 95 patients with various indications. Fluoroscopic guided percutaneous placement of peritoneal catheters is a safe, minimally invasive, and effective alternative to open surgical or laparoscopic placement.

Immediate implant placement and provisionalization with simultaneous guided bone regeneration in the esthetic zone

Directory of Open Access Journals (Sweden)

Chih-Long Chen

2011-03-01

Full Text Available The procedure for immediate implant placement and provisionalization is time-saving, possibly with only one surgical intervention required, although allowing maximal preservation of peri-implant tissues. In this case, we extracted a fractured maxillary right central incisor of a 46-year-old woman with high esthetic expectations, and a transmucosal implant was immediately installed. Simultaneous guided bone regeneration was performed to correct the defects at the facial side of the socket and augment the alveolar ridge horizontally. Primary stability of the implant body and wound closure without tension were confirmed. Connection of a 15° angled abutment and fabrication of a provisional acrylic resin crown without occlusal contact were also completed in the same appointment. After intensive follow-up and soft-tissue molding for 6 months, the customized zirconia abutment and all-ceramic crown were definitively fabricated. During the 18-month follow-up period, the patient was satisfied with the esthetic and functional results.

SU-F-P-40: Analysis of Pelvic Lymph Node Margin Using Prostate Fiducial Markers, for SBRT Treatments

Energy Technology Data Exchange (ETDEWEB)

Torres, J; Castro Pena, P; Garrigo, E; Zunino, S; Venencia, C [Instituto de Radioterapia - Fundacion Marie Curie, Cordoba (Argentina)

2016-06-15

Purpose: The use of fiducials markers in prostate treatment allows a precise localization of this volume. Typical prostate SBRT margins with fiducials markers are 5mm in all directions, except toward the rectum, where 3mm is used. For some patients nearby pelvic lymph nodes with 5mm margin need to be irradiate assuming that its localization is linked to the prostate fiducial markers instead of bony anatomy. The purpose of this work was to analyze the geometric impact of locate the lymph node regions through the patient positioning by prostate fiducial markers. Methods: 10 patients with prostate SBRT with lymph nodes irradiation were selected. Each patient had 5 implanted titanium fiducial markers. A Novalis TX (BrainLAB-Varian) with ExacTrac and aSi1000 portal image was used. Treatment plan uses 11 beams with a dose prescription (D95%) of 40Gy to the prostate and 25Gy to the lymph node in 5 fractions. Daily positioning was carried out by ExacTrac system based on the implanted fiducials as the reference treatment position; further position verification was performed using the ExacTrac and two portal images (gantry angle 0 and 90) based on bony structures. Comparison between reference position with bony based ExacTrac and portal image localization, was done for each treatment fraction Results: A total of 50 positioning analysis were done. The average discrepancy between reference treatment position and ExacTrac based on bony anatomy (pubic area) was 4.2mm [0.3; 11.2]. The discrepancy was <5mm in 61% of the cases and <9mm in 92%. Using portal images the average discrepancy was 3.7mm [0.0; 11.1]. The discrepancy was <5mm in 69% of the cases and <9mm in 96%. Conclusion: Localizing lymph node by prostate fiducial markers may produce large discrepancy as large as 11mm compared to bony based localization. Dosimetric impact of this discrepancy should be studied.

A multi-level rapid prototyping drill guide template reduces the perforation risk of pedicle screw placement in the lumbar and sacral spine.

Science.gov (United States)

Merc, Matjaz; Drstvensek, Igor; Vogrin, Matjaz; Brajlih, Tomaz; Recnik, Gregor

2013-07-01

The method of free-hand pedicle screw placement is generally safe although it carries potential risks. For this reason, several highly accurate computer-assisted systems were developed and are currently on the market. However, these devices have certain disadvantages. We have developed a method of pedicle screw placement in the lumbar and sacral region using a multi-level drill guide template, created with the rapid prototyping technology and have validated it in a clinical study. The aim of the study was to manufacture and evaluate the accuracy of a multi-level drill guide template for lumbar and first sacral pedicle screw placement and to compare it with the free-hand technique under fluoroscopy supervision. In 2011 and 2012, a randomized clinical trial was performed on 20 patients. 54 screws were implanted in the trial group using templates and 54 in the control group using the fluoroscopy-supervised free-hand technique. Furthermore, applicability for the first sacral level was tested. Preoperative CT-scans were taken and templates were designed using the selective laser sintering method. Postoperative evaluation and statistical analysis of pedicle violation, displacement, screw length and deviation were performed for both groups. The incidence of cortex perforation was significantly reduced in the template group; likewise, the deviation and displacement level of screws in the sagittal plane. In both groups there was no significantly important difference in deviation and displacement level in the transversal plane as not in pedicle screw length. The results for the first sacral level resembled the main investigated group. The method significantly lowers the incidence of cortex perforation and is therefore potentially applicable in clinical practice, especially in some selected cases. The applied method, however, carries a potential for errors during manufacturing and practical usage and therefore still requires further improvements.

Global Geodesy Using GPS Without Fiducial Sites

Science.gov (United States)

Heflin, Michael B.; Blewitt, Geoffrey

1994-01-01

Global Positioning System, GPS, used to make global geodetic measurements without use of fiducial site coordinates. Baseline lengths and geocentric radii for each site determined without having to fix any site coordinates. Given n globally distributed sites, n baseline lengths and n geocentric radii form polyhedron with each site at vertex and with geocenter at intersection of all radii. Geodetic information derived from structure of polyhedron and its change with time. Approach applied to any global geodetic technique.

USES 2.0, The Uniform System for the Evaluation of Substances, version 2.0 ; supplement to EUSES

NARCIS (Netherlands)

Linders JBHJ; Jager DT; CSR; ECO

1997-01-01

This interim report describes the updated risk assessment system for agricultural and non-agricultural pesticides. It will be integrated with the European Union System for the Evaluation of Substances, EUSES 1.0, into USES 2.0, the second version of the Uniform System for the Evaluation of

MRI-alone radiation therapy planning for prostate cancer: Automatic fiducial marker detection

International Nuclear Information System (INIS)

Ghose, Soumya; Mitra, Jhimli; Rivest-Hénault, David; Fazlollahi, Amir; Fripp, Jurgen; Dowling, Jason A.; Stanwell, Peter; Pichler, Peter; Sun, Jidi; Greer, Peter B.

2016-01-01

Purpose: The feasibility of radiation therapy treatment planning using substitute computed tomography (sCT) generated from magnetic resonance images (MRIs) has been demonstrated by a number of research groups. One challenge with an MRI-alone workflow is the accurate identification of intraprostatic gold fiducial markers, which are frequently used for prostate localization prior to each dose delivery fraction. This paper investigates a template-matching approach for the detection of these seeds in MRI. Methods: Two different gradient echo T1 and T2* weighted MRI sequences were acquired from fifteen prostate cancer patients and evaluated for seed detection. For training, seed templates from manual contours were selected in a spectral clustering manifold learning framework. This aids in clustering “similar” gold fiducial markers together. The marker with the minimum distance to a cluster centroid was selected as the representative template of that cluster during training. During testing, Gaussian mixture modeling followed by a Markovian model was used in automatic detection of the probable candidates. The probable candidates were rigidly registered to the templates identified from spectral clustering, and a similarity metric is computed for ranking and detection. Results: A fiducial detection accuracy of 95% was obtained compared to manual observations. Expert radiation therapist observers were able to correctly identify all three implanted seeds on 11 of the 15 scans (the proposed method correctly identified all seeds on 10 of the 15). Conclusions: An novel automatic framework for gold fiducial marker detection in MRI is proposed and evaluated with detection accuracies comparable to manual detection. When radiation therapists are unable to determine the seed location in MRI, they refer back to the planning CT (only available in the existing clinical framework); similarly, an automatic quality control is built into the automatic software to ensure that all gold

MRI-alone radiation therapy planning for prostate cancer: Automatic fiducial marker detection

Energy Technology Data Exchange (ETDEWEB)

Ghose, Soumya, E-mail: soumya.ghose@case.edu; Mitra, Jhimli [Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio 44106 and CSIRO Health and Biosecurity, The Australian e-Health & Research Centre, Herston, QLD 4029 (Australia); Rivest-Hénault, David; Fazlollahi, Amir; Fripp, Jurgen; Dowling, Jason A. [CSIRO Health and Biosecurity, The Australian e-Health & Research Centre, Herston, QLD 4029 (Australia); Stanwell, Peter [School of health sciences, The University of Newcastle, Newcastle, NSW 2308 (Australia); Pichler, Peter [Department of Radiation Oncology, Cavalry Mater Newcastle Hospital, Newcastle, NSW 2298 (Australia); Sun, Jidi; Greer, Peter B. [School of Mathematical and Physical Sciences, The University of Newcastle, Newcastle, NSW 2308, Australia and Department of Radiation Oncology, Cavalry Mater Newcastle Hospital, Newcastle, NSW 2298 (Australia)

2016-05-15

Purpose: The feasibility of radiation therapy treatment planning using substitute computed tomography (sCT) generated from magnetic resonance images (MRIs) has been demonstrated by a number of research groups. One challenge with an MRI-alone workflow is the accurate identification of intraprostatic gold fiducial markers, which are frequently used for prostate localization prior to each dose delivery fraction. This paper investigates a template-matching approach for the detection of these seeds in MRI. Methods: Two different gradient echo T1 and T2* weighted MRI sequences were acquired from fifteen prostate cancer patients and evaluated for seed detection. For training, seed templates from manual contours were selected in a spectral clustering manifold learning framework. This aids in clustering “similar” gold fiducial markers together. The marker with the minimum distance to a cluster centroid was selected as the representative template of that cluster during training. During testing, Gaussian mixture modeling followed by a Markovian model was used in automatic detection of the probable candidates. The probable candidates were rigidly registered to the templates identified from spectral clustering, and a similarity metric is computed for ranking and detection. Results: A fiducial detection accuracy of 95% was obtained compared to manual observations. Expert radiation therapist observers were able to correctly identify all three implanted seeds on 11 of the 15 scans (the proposed method correctly identified all seeds on 10 of the 15). Conclusions: An novel automatic framework for gold fiducial marker detection in MRI is proposed and evaluated with detection accuracies comparable to manual detection. When radiation therapists are unable to determine the seed location in MRI, they refer back to the planning CT (only available in the existing clinical framework); similarly, an automatic quality control is built into the automatic software to ensure that all gold

Transesophageal Echocardiography-Guided Epicardial Left Ventricular Lead Placement by Video-Assisted Thoracoscopic Surgery in Nonresponders to Biventricular Pacing and Previous Chest Surgery.

Science.gov (United States)

Schroeder, Carsten; Chung, Jane M; Mackall, Judith A; Cakulev, Ivan T; Patel, Aaron; Patel, Sunny J; Hoit, Brian D; Sahadevan, Jayakumar

2018-06-14

The aim of the study was to study the feasibility, safety, and efficacy of transesophageal echocardiography-guided intraoperative left ventricular lead placement via a video-assisted thoracoscopic surgery approach in patients with failed conventional biventricular pacing. Twelve patients who could not have the left ventricular lead placed conventionally underwent epicardial left ventricular lead placement by video-assisted thoracoscopic surgery. Eight patients had previous chest surgery (66%). Operative positioning was a modified far lateral supine exposure with 30-degree bed tilt, allowing for groin and sternal access. To determine the optimal left ventricular location for lead placement, the left ventricular surface was divided arbitrarily into nine segments. These segments were transpericardially paced using a hand-held malleable pacing probe identifying the optimal site verified by transesophageal echocardiography. The pacing leads were screwed into position via a limited pericardiotomy. The video-assisted thoracoscopic surgery approach was successful in all patients. Biventricular pacing was achieved in all patients and all reported symptomatic benefit with reduction in New York Heart Association class from III to I-II (P = 0.016). Baseline ejection fraction was 23 ± 3%; within 1-year follow-up, the ejection fraction increased to 32 ± 10% (P = 0.05). The mean follow-up was 566 days. The median length of hospital stay was 7 days with chest tube removal between postoperative days 2 and 5. In patients who are nonresponders to conventional biventricular pacing, intraoperative left ventricular lead placement using anatomical and functional characteristics via a video-assisted thoracoscopic surgery approach is effective in improving heart failure symptoms. This optimized left ventricular lead placement is feasible and safe. Previous chest surgery is no longer an exclusion criterion for a video-assisted thoracoscopic surgery approach.

SU-E-T-507: Interfractional Variation of Fiducial Marker Position During HDR Brachytherapy with Cervical Interstitial Needle Template

Energy Technology Data Exchange (ETDEWEB)

Shen, S; Kim, R; Benhabib, S; Araujo, J; Burnett, L; Duan, J; Popple, R; Wu, X; Cardan, R; Brezovich, I [UniversityAlabama Birmingham, Birmingham, AL (United Kingdom)

2014-06-01

Purpose: HDR brachytherapy using interstitial needle template for cervical cancer is commonly delivered in 4-5 fractions. Routine verification of needle positions before each fraction is often based on radiographic imaging of implanted fiducial markers. The current study evaluated interfractional displacement of implanted fiducial markers using CT images. Methods: 9 sequential patients with cervical interstitial needle implants were evaluated. The superior and inferior borders of the target volumes were defined by fiducial markers in planning CT. The implant position was verified with kV orthogonal images before each fraction. A second CT was acquired prior 3rd fraction (one or 2 days post planning CT). Distances from inferior and superior fiducial markers to pubic symphysis plane (perpendicular to vaginal obtulator)were measured. Distance from needle tip of a reference needle (next to the inferior marker) to the pubic symphysis plane was also determined. The difference in fiducial marker distance or needle tip distance between planning CT and CT prior 3rd fraction were measured to assess markers migration and needle displacement. Results: The mean inferior marker displacement was 4.5 mm and ranged 0.9 to 11.3 mm. The mean superior marker displacement was 2.7 mm and ranged 0 to 10.4 mm. There was a good association between inferior and superior marker displacement (r=0.95). Mean averaged inferior and superior marker displacement was 3.3 mm and ranged from 0.1 to 10.9 mm, with a standard deviation of 3.2 mm. The mean needle displacement was 5.6 mm and ranged 0.2 to 15.6 mm. Needle displacements were reduced (p<0.05) after adjusting according to needle-to-fiducials distance. Conclusion: There were small fiducial marker displacements between HDR fractions. Our study suggests a target margin of 9.7 mm to cover interfractional marker displacements (in 95% cases) for pretreatment verification based on radiographic imaging.

Enabling image fusion for a CT guided needle placement robot

Science.gov (United States)

Seifabadi, Reza; Xu, Sheng; Aalamifar, Fereshteh; Velusamy, Gnanasekar; Puhazhendi, Kaliyappan; Wood, Bradford J.

2017-03-01

Purpose: This study presents development and integration of hardware and software that enables ultrasound (US) and computer tomography (CT) fusion for a FDA-approved CT-guided needle placement robot. Having real-time US image registered to a priori-taken intraoperative CT image provides more anatomic information during needle insertion, in order to target hard-to-see lesions or avoid critical structures invisible to CT, track target motion, and to better monitor ablation treatment zone in relation to the tumor location. Method: A passive encoded mechanical arm is developed for the robot in order to hold and track an abdominal US transducer. This 4 degrees of freedom (DOF) arm is designed to attach to the robot end-effector. The arm is locked by default and is released by a press of button. The arm is designed such that the needle is always in plane with US image. The articulated arm is calibrated to improve its accuracy. Custom designed software (OncoNav, NIH) was developed to fuse real-time US image to a priori-taken CT. Results: The accuracy of the end effector before and after passive arm calibration was 7.07mm +/- 4.14mm and 1.74mm +/-1.60mm, respectively. The accuracy of the US image to the arm calibration was 5mm. The feasibility of US-CT fusion using the proposed hardware and software was demonstrated in an abdominal commercial phantom. Conclusions: Calibration significantly improved the accuracy of the arm in US image tracking. Fusion of US to CT using the proposed hardware and software was feasible.

Assessment of prostate motion during radiotherapy using fiducial markers and CT reconstruction

International Nuclear Information System (INIS)

Crook, J.; Salhani, D.; Yang, H.; Deshaies, Y.; Raymond, Y.; Malone, S.; Esche, B.

1996-01-01

Purpose: To assess changes in prostate position during a course of pelvic radiotherapy for prostate cancer using fiducial markers and sequential planning CT scans. Methods and Materials: Three gold seeds are implanted in the apex, base and posterior aspect of the prostate under trans-rectal ultrasound guidance prior to initial simulation. In addition, treatment planning CT scans with 5 mm slices through the prostate are obtained at 0 and 40 Gy. Patients are scanned, simulated and treated with full bladder and are positioned using a standard foam leg support from the knees to the ankles. Prostate movement is assessed by two independent methods: [1] Localization of the fiducial markers using orthogonal simulator films taken just prior to the initial and boost stages of treatment and [2] a three-dimensional reconstruction methodology using CT datasets again obtained prior to the initial and boost stages. In both cases, rigid-body transformations of selected bony landmarks were used to eliminate patient movement between simulations and CT scans. For CT reconstruction, high order polynomial extrapolation and Chebychev multi-domain interpolation methods are employed to determine the coordinates of the fiducial markers. Prostatic movement, between initial and boost imaging, is estimated from the variance of the position of the corresponding seeds. Results: At present, seed data is available for sixty (60) patients. An additional nineteen (19) patients were excluded because of suspected seed migration > 3.0 mm or a localization uncertainty > 1.5 mm. The range of movement seen in the lateral direction is -0.25 to 0.48 cm (mean: 0.11, SD: 0.15), in the cranio-caudal direction -1.57 to 0.64 cm (mean: 0.59 SD: 0.48), and in the antero-posterior direction -1.91 to .47 cm (mean: 0.53, SD: 0.39). Results disclosed 53% of the patients with a caudal shift of the prostate > 0.5 cm and 10% > 1.0 cm. Further, 60% of the patients showed a posterior shift > 0.5 cm and 27% > 1.0 cm. CT

Effect of Ultrasound-Guided Placement of Difficult-to-Place Peripheral Venous Catheters

DEFF Research Database (Denmark)

Partovi-Deilami, Kohyar; Nielsen, Jesper K.; Møller, Ann M.

2016-01-01

operated by nurse anesthetists for these patients. This prospective observational study with a pre/post design focused on inpatients with DIVA referred for PVC placement, a service provided by nurse anesthetists in most Scandinavian hospitals. The rate of success, procedure time, number of skin punctures......) with ultrasound. Procedure time was reduced from 20 to 10 minutes, discomfort was unchanged, and the median number of skin punctures decreased from 3 to 2. The incidence of central venous catheter placement dropped from 34% to 7%. Implementation of a training program and a mobile service in which nurse......, discomfort, catheter size, location, and incidence of central venous catheter placement are reported before and after implementation of a training program and a mobile service using ultrasound to place difficult-to-place PVCs. The success rate increased from 0% (0 of 33 patients) to 83% (58 of 70 patients...

Research of time fiducial and imaging VISAR laser for Shenguang-III laser facility

Science.gov (United States)

Zhang, Rui; Wang, Zhenguo; Tian, Xiaocheng; Zhou, Dandan; Zhu, Na; Wang, Jianjun; Li, Mingzhong; Xu, Dangpeng; Dang, Zhao; Hu, Dongxia; Zhu, Qihua; Zheng, Wanguo; Wang, Feng

2015-10-01

Time fiducial laser is an important tool for the precise measurement in high energy density physics experiments. The VISAR probe laser is also vital for shock wave diagnostics in ICF experiments. Here, time fiducial laser and VISAR light were generated from one source on SG-III laser facility. After generated from a 1064-nm DFB laser, the laser is modulated by an amplitude modulator driven by 10 GS/s arbitrary waveform generator. Using time division multiplexing technology, the ten-pulse time fiducial laser and the 20-ns VISAR pulse were split by a 1×2 multiplexer and then chosen by two acoustic optic modulators. Using the technique, cost of the system was reduced. The technologies adopted in the system also include pulse polarization stabilization, high precision fiber coupling and energy transmission. The time fiducial laser generated synchronized 12-beam 2ω and 4-beam 3ω laser, providing important reference marks for different detectors and making it convenient for the analysis of diagnostic data. After being amplified by fiber amplifiers and Nd:YAG rod amplifiers, the VISAR laser pulse was frequency-converted to 532-nm pulse by a thermally controlled LBO crystal with final output energy larger than 20 mJ. Finally, the green light was coupled into a 1-mm core diameter, multimode fused silica optical fiber and propagated to the imaging VISAR. The VISAR laser has been used in the VISAR diagnostic physics experiments. Shock wave loading and slowdown processes were measured. Function to measure velocity history of shock wave front movement in different kinds of materials was added to the SG-III laser facility.

Endoscopic ultrasound rendezvous for bile duct access using a transduodenal approach: cumulative experience at a single center. A case series.

Science.gov (United States)

Kim, Y S; Gupta, K; Mallery, S; Li, R; Kinney, T; Freeman, M L

2010-06-01

Endoscopic ultrasound (EUS)-assisted biliary access is utilized when conventional endoscopic retrograde cholangiopancreatography (ERCP) fails. We report a 10-year experience utilizing a transduodenal EUS rendezvous via a transpapillary route without dilation of the transduodenal tract, followed by immediate ERCP access. Patients included all EUS-guided rendezvous procedures for biliary access that were performed following ERCP failure. EUS-assisted bile duct puncture was performed via a transduodenal approach and a guide wire was advanced through the papilla without any dilation or bougienage of the tract; ERCP was performed immediately afterwards. EUS-assisted biliary rendezvous was attempted in 15 patients (mean age 66 +/- 18.2 years; malignant = 10, benign = 5). Mean diameter of measured bile ducts was 14.3 +/- 5.17 mm (range 4-23 mm). The reasons for initial ERCP failure were tumor infiltration or edema (n = 9), intradiverticular papilla (n = 2), pre-existing duodenal stent (n = 1), and anatomic anomalies (n = 3). Successful EUS-guided bile duct puncture and wire passage were achieved in all 15 patients (100 %), with drainage being successful in 12 / 15 (80 %). Failures occurred in three patients due to inability to traverse the biliary stricture (n = 2) or dissection of a choledochocele with the guide wire (n = 1); all were subsequently drained via percutaneous methods. Stents placed were metallic in eight patients and plastic in four. Complications consisted of moderate pancreatitis after a difficult ERCP attempt in one patient, and bacteremia after percutaneous biliary drainage in another. There were no instances of perforation, extraluminal air or fluid collections. EUS-assisted biliary drainage utilizing a transduodenal rendezvous approach demonstated a high success rate without any complications directly attributable to the EUS access. Advantages over percutaneous biliary and other methods of EUS biliary access include performance under the same

A Fiducial Reference Stie for Satellite Altimetry in Crete, Greece

Science.gov (United States)

Mertikas, Stelios; Donlon, Craig; Mavrocordatos, Constantin; Bojkov, Bojan; Femenias, Pierre; Parrinello, Tommaso; Picot, Nicolas; Desjonqueres, Jean-Damien; Andersen, Ole Baltazar

2016-08-01

With the advent of diverse satellite altimeters and variant measuring techniques, it has become mature in the scientific community, that an absolute reference Cal/Val site is regularly maintained to define, monitor, control the responses of any altimetric system.This work sets the ground for the establishment of a Fiducial Reference Site for ESA satellite altimetry in Gavdos and West Crete, Greece. It will consistently and reliably determine (a) absolute altimeter biases and their drifts; (b) relative bias among diverse missions; but also (c) continuously and independently connect different missions, on a common and reliable reference and also to SI-traceable measurements. Results from this fiducial reference site will be based on historic Cal/Val site measurement records, and will be the yardstick for building up capacity for monitoring climate change. This will be achieved by defining and assessing any satellite altimeter measurements to known, controlled and absolute reference signals with different techniques, processes and instrumentation.

Robust and efficient fiducial tracking for augmented reality in HD-laparoscopic video streams

Science.gov (United States)

Mueller, M.; Groch, A.; Baumhauer, M.; Maier-Hein, L.; Teber, D.; Rassweiler, J.; Meinzer, H.-P.; Wegner, In.

2012-02-01

Augmented Reality (AR) is a convenient way of porting information from medical images into the surgical field of view and can deliver valuable assistance to the surgeon, especially in laparoscopic procedures. In addition, high definition (HD) laparoscopic video devices are a great improvement over the previously used low resolution equipment. However, in AR applications that rely on real-time detection of fiducials from video streams, the demand for efficient image processing has increased due to the introduction of HD devices. We present an algorithm based on the well-known Conditional Density Propagation (CONDENSATION) algorithm which can satisfy these new demands. By incorporating a prediction around an already existing and robust segmentation algorithm, we can speed up the whole procedure while leaving the robustness of the fiducial segmentation untouched. For evaluation purposes we tested the algorithm on recordings from real interventions, allowing for a meaningful interpretation of the results. Our results show that we can accelerate the segmentation by a factor of 3.5 on average. Moreover, the prediction information can be used to compensate for fiducials that are temporarily occluded or out of scope, providing greater stability.

Location of pulmonary modules prior to video thoracoscopic surgery by CT-guided hook wire placement: Preliminary study

International Nuclear Information System (INIS)

Ferreiras, J.; Salmeron, I.; Bustos Garcia de Castro, A.; Hernando, F.; Gomez, A.; Torres, A.

1996-01-01

Despite the efficacy of computerized tomography (CT) or radiologically-guided percutaneous biopsy and that offluoroscopically-guided trans bronchial biopsy in characterizing pulmonary nodules, it is not always possible to determine the etiology using these techniques, making it necessary to resort to thoracotomy. Recent developments in endoscopicsurgery equipment and the availability of advance video imaging technology have extended the indications for both diagnostic and therapeutic thoracoscopy. Thus, a number of procedures that previously could only be performed bymeans of thoracotomy, such as resection of peripheral pulmonary nodules, can nowbe carried out by means of video thoracoscopic (VT) surgery. Palpation orvisual location of pulmonary nodules by thoracoscopy is essential but is not always possible when the nodules measure less than 20 mm or when their location is not subpleural. In such cases, a procedure for their prior location is useful. In eight patients with pulmonary nodules who were to undergo subsequent VT surgery, the attempt was made to locate the nodules by CT-guided placementof a hook wire, similar to that employed in breast, and methylene blue injection. The hook wire was correctly introduced without significant complications in all eight cases. The eight nodules were successfully resected during the thoracoscopic procedure, in which the hook wire and methylene blue staining were of great assistance. In certain cases, the location of pulmonary nodules by means of CT-guidehook wire placement and methylene blue injection allows the video thoracoscopic resection of lesions of difficult access. (Author)

Development of automatic navigation measuring system using template-matching software in image guided neurosurgery

International Nuclear Information System (INIS)

Watanabe, Yohei; Hayashi, Yuichiro; Fujii, Masazumi; Wakabayashi, Toshihiko; Kimura, Miyuki; Tsuzaka, Masatoshi; Sugiura, Akihiro

2010-01-01

An image-guided neurosurgery and neuronavigation system based on magnetic resonance imaging has been used as an indispensable tool for resection of brain tumors. Therefore, accuracy of the neuronavigation system, provided by periodic quality assurance (QA), is essential for image-guided neurosurgery. Two types of accuracy index, fiducial registration error (FRE) and target registration error (TRE), have been used to evaluate navigation accuracy. FRE shows navigation accuracy on points that have been registered. On the other hand, TRE shows navigation accuracy on points such as tumor, skin, and fiducial markers. This study shows that TRE is more reliable than FRE. However, calculation of TRE is a time-consuming, subjective task. Software for QA was developed to compute TRE. This software calculates TRE automatically by an image processing technique, such as automatic template matching. TRE was calculated by the software and compared with the results obtained by manual calculation. Using the software made it possible to achieve a reliable QA system. (author)

[Diagnostic utility of endoscopic ultrasonography elastography and contrast-enhanced harmonic endoscopic ultrasonography in a patient with type 2 autoimmune pancreatitis].

Science.gov (United States)

Yokode, Masataka; Shiomi, Hideyuki; Itai, Ryosuke; Mikami, Sakae; Yamashita, Yukimasa; Nakano, Ryota; Ezaki, Takeshi; Masuda, Atsuhiro; Zen, Yoh

2018-01-01

A referring hospital diagnosed a 57-year-old man with a pancreatic head mass. The initial endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) was inconclusive because of the small sample size. Endoscopic ultrasonography elastography (EUS-EG) and contrast-enhanced harmonic endoscopic ultrasonography (CE-EUS), conducted at our institute, raised the possibility of mass-forming pancreatitis or autoimmune pancreatitis (AIP). A repeat EUS-FNA revealed inflammatory changes, including a neutrophilic duct injury suggestive of type 2 AIP. The pancreatic lesion responded well to the steroid therapy. The present case suggests that EUS-EG and CE-EUS may be useful for diagnostic exclusion of pancreatic cancers, and the combined use of EUS-EG and CE-EUS, with EUS-FNA, may help characterize inflammatory pancreatic lesions.

W+W- production at the LHC. Fiducial cross sections and distributions in NNLO QCD

International Nuclear Information System (INIS)

Grazzini, Massimiliano; Wiesemann, Marius; Kallweit, Stefan; California Univ., Santa Barbara, CA; Pozzorini, Stefano; California Univ., Santa Barbara, CA; Rathlev, Dirk

2016-05-01

We consider QCD radiative corrections to W + W - production at the LHC and present the first fully differential predictions for this process at next-to-next-to-leading order (NNLO) in perturbation theory. Our computation consistently includes the leptonic decays of the W bosons, taking into account spin correlations, off-shell effects and non-resonant contributions. Detailed predictions are presented for the different-flavour channel pp→μ + e - ν μ anti ν e +X at √(s)=8 and 13 TeV. In particular, we discuss fiducial cross sections and distributions in the presence of standard selection cuts used in experimental W + W - and H→W + W - analyses at the LHC. The inclusive W + W - cross section receives large NNLO corrections, and, due to the presence of a jet veto, typical fiducial cuts have a sizeable influence on the behaviour of the perturbative expansion. The availability of differential NNLO predictions, both for inclusive and fiducial observables, will play an important role in the rich physics programme that is based on precision studies of W + W - signatures at the LHC.

K.S. Micro‑Implant Placement Guide

African Journals Online (AJOL)

after being injured by temporary orthodontic anchorage devices,[3] ... and does not disturb the existing appliance system, clearly ... The wire guide is fabricated using round 0.018 or 0.020 ... their clinical efficiency in anchorage control.

II Brazilian consensus statement on endoscopic ultrasonography.

Science.gov (United States)

Maluf-Filho, Fauze; de Oliveira, Joel Fernandez; Mendonça, Ernesto Quaresma; Carbonari, Augusto; Maciente, Bruno Antônio; Salomão, Bruno Chaves; Medrado, Bruno Frederico; Dotti, Carlos Marcelo; Lopes, César Vivian; Braga, Cláudia Utsch; M Dutra, Daniel Alencar; Retes, Felipe; Nakao, Frank; de Sousa, Giovana Biasia; de Paulo, Gustavo Andrade; Ardengh, Jose Celso; Dos Santos, Juliana Bonfim; Sampaio, Luciana Moura; Okawa, Luciano; Rossini, Lucio; de Brito Cardoso, Manoel Carlos; Ribeiro Camunha, Marco Antonio; Clarêncio, Marcos; Lera Dos Santos, Marcos Eduardo; Franco, Matheus; Schneider, Nutianne Camargo; Mascarenhas, Ramiro; Roda, Rodrigo; Matuguma, Sérgio; Guaraldi, Simone; Figueiredo, Viviane

2017-01-01

At the time of its introduction in the early 80s, endoscopic ultrasonography (EUS) was indicated for diagnostic purposes. Recently, EUS has been employed to assist or to be the main platform of complex therapeutic interventions. From a series of relevant new topics in the literature and based on the need to complement the I Brazilian consensus on EUS, twenty experienced endosonographers identified and reviewed the pertinent literature in databases. The quality of evidence, strength of recommendations, and level of consensus were graded and voted on. Consensus was reached for eight relevant topics: treatment of gastric varices, staging of nonsmall cell lung cancer, biliary drainage, tissue sampling of subepithelial lesions (SELs), treatment of pancreatic fluid collections, tissue sampling of pancreatic solid lesions, celiac neurolysis, and evaluation of the incidental pancreatic cysts. There is a high level of evidence for staging of nonsmall cell lung cancer; biopsy of SELs as the safest method; unilateral and bilateral injection techniques are equivalent for EUS-guided celiac neurolysis, and in patients with visible ganglia, celiac ganglia neurolysis appears to lead to better results. There is a moderate level of evidence for: yield of tissue sampling of pancreatic solid lesions is not influenced by the needle shape, gauge, or employed aspiration technique; EUS-guided and percutaneous biliary drainage present similar clinical success and adverse event rates; plastic and metallic stents are equivalent in the EUS-guided treatment of pancreatic pseudocyst. There is a low level of evidence in the routine use of EUS-guided treatment of gastric varices.

CT-guided fixation of sacral fractures and sacrolilac joint disruptions

International Nuclear Information System (INIS)

Nelson, D.W.; Duwelius, P.

1990-01-01

Placement of sacral fixation screws at surgery is performed blindly (ie, by palpation). The authors of this paper employed CT to localize the screw between the neutral foramina and anterior sacral cortex and to decrease the morbidity associated with general anesthesia and surgery. Six patients underwent CT-guided sacral fixation performed by means of the 7.0 mm A0 cannulated screw system. All patients had reducible vertical sacral fractures or sacroiliac joint disruptions. Following placement of an epidural catheter for anesthesia, patients were scanned in the prone or decubitus position. Measurements for placement of the guide pin were made from the preliminary scans. Following CT confirmation of satisfactory guide pin placement across the fracture, the screw track was drilled, the screw length was determined, and the fixation screw was placed in position. A CT scan was obtained to evaluate the final position of the screw

Percutaneous placement of peritoneal port-catheter in oncologic patients

International Nuclear Information System (INIS)

Orsi, Franco; Vigna, Paolo Della; Bonomo, Guido; Penco, Silvia; Lovati, Elena; Bellomi, Massimo

2004-01-01

The aim of this paper is to describe the technique of percutaneous ultrasound (US)-guided placement of a peritoneal port-catheter in an interventional radiological setting. Nineteen patients with peritoneal carcinomatosis were selected for intraperitoneal port-catheter placement in order to perform intracavitary receptor-immuno- or radio-immunotherapy with Ytrium-90. All the procedures were performed percutaneously under US and fluoro guidance; the insertion site for catheters was chosen according to abdominal conditions and US findings: all devices were implanted at the lower abdominal quadrants. All patients were followed up with CT and US according to the therapy protocol. The procedure was successfully completed in 15/19 patients, in 4 being contraindicated by peritoneal adhesions. No procedure-related complications and device occlusions during therapy were observed; one catheter displaced 7 months later the placement. In our experience, this procedure was feasible, reliable and easy to perform, allowing the correct administration of the planned intracavitary therapy. Peritoneal adhesions are the main limitation of peritoneal port placement. (orig.)

Comparison of Histologic Core Portions Acquired from a Core Biopsy Needle and a Conventional Needle in Solid Mass Lesions: A Prospective Randomized Trial.

Science.gov (United States)

Lee, Ban Seok; Cho, Chang-Min; Jung, Min Kyu; Jang, Jung Sik; Bae, Han Ik

2017-07-15

The superiority of endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) over EUS-guided fine needle aspiration (EUS-FNA) remains controversial. Given the lack of studies analyzing histologic specimens acquired from EUS-FNB or EUS-FNA, we compared the proportion of the histologic core obtained from both techniques. A total of 58 consecutive patients with solid mass lesions were enrolled and randomly assigned to the EUS-FNA or EUS-FNB groups. The opposite needle was used after the failure of core tissue acquisition using the initial needle with up to three passes. Using computerized analyses of the scanned histologic slide, the overall area and the area of the histologic core portion in specimens obtained by the two techniques were compared. No significant differences were identified between the two groups with respect to demographic and clinical characteristics. Fewer needle passes were required to obtain core specimens in the FNB group (pcore (11.8%±19.5% vs 8.0%±11.1%, p=0.376) or in the diagnostic accuracy (80.6% vs 81.5%, p=0.935) between two groups. The proportion of histologic core and the diagnostic accuracy were comparable between the FNB and FNA groups. However, fewer needle passes were required to establish an accurate diagnosis in EUS-FNB.

Quality assurance procedure for a gamma guided stereotactic breast biopsy system.

Science.gov (United States)

Welch, Benjamin L; Brem, Rachel; Black, Rachel; Majewski, Stan

2006-01-01

A quality assurance procedure has been developed for a prototype gamma-ray guided stereotactic biopsy system. The system consists of a compact small-field-of-view gamma-ray camera mounted to the rotational arm of a Lorad stereotactic biopsy system. The small-field-of-view gamma-ray camera has been developed for clinical applications where mammographic X-ray localization is not possible. Marker sources that can be imaged with the gamma-camera have been designed and built for quality assurance testing and to provide a fiducial reference mark. An algorithm for determining the three dimensional location of a region of interest, such as a lesion, relative to the fiducial mark has been implemented into the software control of the camera. This system can be used to determine the three-dimensional location of a region of interest from a stereo pair of images and that information can be used to guide a biopsy needle to that site. Point source phantom tests performed with the system have demonstrated that the camera can be used to localize a point of interest to within 1 mm, which is satisfactory for its use in needle localization.

Robust augmented reality registration method for localization of solid organs' tumors using CT-derived virtual biomechanical model and fluorescent fiducials.

Science.gov (United States)

Kong, Seong-Ho; Haouchine, Nazim; Soares, Renato; Klymchenko, Andrey; Andreiuk, Bohdan; Marques, Bruno; Shabat, Galyna; Piechaud, Thierry; Diana, Michele; Cotin, Stéphane; Marescaux, Jacques

2017-07-01

Augmented reality (AR) is the fusion of computer-generated and real-time images. AR can be used in surgery as a navigation tool, by creating a patient-specific virtual model through 3D software manipulation of DICOM imaging (e.g., CT scan). The virtual model can be superimposed to real-time images enabling transparency visualization of internal anatomy and accurate localization of tumors. However, the 3D model is rigid and does not take into account inner structures' deformations. We present a concept of automated AR registration, while the organs undergo deformation during surgical manipulation, based on finite element modeling (FEM) coupled with optical imaging of fluorescent surface fiducials. Two 10 × 1 mm wires (pseudo-tumors) and six 10 × 0.9 mm fluorescent fiducials were placed in ex vivo porcine kidneys (n = 10). Biomechanical FEM-based models were generated from CT scan. Kidneys were deformed and the shape changes were identified by tracking the fiducials, using a near-infrared optical system. The changes were registered automatically with the virtual model, which was deformed accordingly. Accuracy of prediction of pseudo-tumors' location was evaluated with a CT scan in the deformed status (ground truth). In vivo: fluorescent fiducials were inserted under ultrasound guidance in the kidney of one pig, followed by a CT scan. The FEM-based virtual model was superimposed on laparoscopic images by automatic registration of the fiducials. Biomechanical models were successfully generated and accurately superimposed on optical images. The mean measured distance between the estimated tumor by biomechanical propagation and the scanned tumor (ground truth) was 0.84 ± 0.42 mm. All fiducials were successfully placed in in vivo kidney and well visualized in near-infrared mode enabling accurate automatic registration of the virtual model on the laparoscopic images. Our preliminary experiments showed the potential of a biomechanical model with fluorescent

Development of a robust MRI fiducial system for automated fusion of MR-US abdominal images.

Science.gov (United States)

Favazza, Christopher P; Gorny, Krzysztof R; Callstrom, Matthew R; Kurup, Anil N; Washburn, Michael; Trester, Pamela S; Fowler, Charles L; Hangiandreou, Nicholas J

2018-05-21

We present the development of a two-component magnetic resonance (MR) fiducial system, that is, a fiducial marker device combined with an auto-segmentation algorithm, designed to be paired with existing ultrasound probe tracking and image fusion technology to automatically fuse MR and ultrasound (US) images. The fiducial device consisted of four ~6.4 mL cylindrical wells filled with 1 g/L copper sulfate solution. The algorithm was designed to automatically segment the device in clinical abdominal MR images. The algorithm's detection rate and repeatability were investigated through a phantom study and in human volunteers. The detection rate was 100% in all phantom and human images. The center-of-mass of the fiducial device was robustly identified with maximum variations of 2.9 mm in position and 0.9° in angular orientation. In volunteer images, average differences between algorithm-measured inter-marker spacings and actual separation distances were 0.53 ± 0.36 mm. "Proof-of-concept" automatic MR-US fusions were conducted with sets of images from both a phantom and volunteer using a commercial prototype system, which was built based on the above findings. Image fusion accuracy was measured to be within 5 mm for breath-hold scanning. These results demonstrate the capability of this approach to automatically fuse US and MR images acquired across a wide range of clinical abdominal pulse sequences. © 2018 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

Endoscopic ultrasound-guided biliary drainage using a newly designed metal stent with a thin delivery system: a preclinical study in phantom and porcine models.

Science.gov (United States)

Minaga, Kosuke; Kitano, Masayuki; Itonaga, Masahiro; Imai, Hajime; Miyata, Takeshi; Yamao, Kentaro; Tamura, Takashi; Nuta, Junya; Warigaya, Kenji; Kudo, Masatoshi

2017-12-08

This study was designed to evaluate the feasibility and safety of a newly designed self-expandable metal stent for endoscopic ultrasound-guided biliary drainage (EUS-BD) when it was delivered via three different stent delivery systems: a 7.5Fr delivery catheter with a bullet-shaped tip (7.5Fr-bullet), a 7Fr catheter with a bullet-shaped tip (7Fr-bullet), or a 7Fr catheter with a tee-shaped tip (7Fr-tee). This experimental study utilized a porcine model of biliary dilatation involving ten pigs. In the animal study, technical feasibility and clinical outcomes of the stent when placed with each of the delivery systems were examined. In addition, a phantom model was used to measure the resistance of these delivery systems to advancement. Phantom experiments showed that, compared with 7Fr-bullet, 7Fr-tee had less resistance force to the advancement of the stent delivery system. EUS-BD was technically successful in all ten pigs. Fistulous tract dilation was necessary in 100% (2/2), 75% (3/4), and 0% (0/4) of the pigs that underwent EUS-BD using 7.5Fr-bullet, 7Fr-bullet, and 7Fr-tee, respectively. There were no procedure-related complications. Our newly designed metal stent may be feasible and safe for EUS-BD, particularly when delivered by 7Fr-tee, because it eliminates the need for fistulous tract dilation.

Fiducial-based monocular 3D displacement measurement of breakwater armour unit models.

CSIR Research Space (South Africa)

Vieira, R

2008-11-01

Full Text Available This paper presents a fiducial-based approach to monitoring the movement of breakwater armour units in a model hall environment. Target symbols with known dimensions are attached to the physical models, allowing the recovery of three...

Treatment outcome of high-dose image-guided intensity-modulated radiotherapy using intra-prostate fiducial markers for localized prostate cancer at a single institute in Japan

International Nuclear Information System (INIS)

Takeda, Ken; Shimizu, Eiji; Abe, Keiko; Shirata, Yuko; Ishikawa, Yohjiro

2012-01-01

Several studies have confirmed the advantages of delivering high doses of external beam radiotherapy to achieve optimal tumor-control outcomes in patients with localized prostate cancer. We evaluated the medium-term treatment outcome after high-dose, image-guided intensity-modulated radiotherapy (IMRT) using intra-prostate fiducial markers for clinically localized prostate cancer. In total, 141 patients with localized prostate cancer treated with image-guided IMRT (76 Gy in 13 patients and 80 Gy in 128 patients) between 2003 and 2008 were enrolled in this study. The patients were classified according to the National Comprehensive Cancer Network-defined risk groups. Thirty-six intermediate-risk patients and 105 high-risk patients were included. Androgen-deprivation therapy was performed in 124 patients (88%) for a median of 11 months (range: 2–88 months). Prostate-specific antigen (PSA) relapse was defined according to the Phoenix-definition (i.e., an absolute nadir plus 2 ng/ml dated at the call). The 5-year actuarial PSA relapse-free survival, the 5-year distant metastasis-free survival, the 5-year cause-specific survival (CSS), the 5-year overall survival (OS) outcomes and the acute and late toxicities were analyzed. The toxicity data were scored according to the Common Terminology Criteria for Adverse Events, version 4.0. The median follow-up was 60 months. The 5-year PSA relapse-free survival rates were 100% for the intermediate-risk patients and 82.2% for the high-risk patients; the 5-year actuarial distant metastasis-free survival rates were 100% and 95% for the intermediate- and high-risk patients, respectively; the 5-year CSS rates were 100% for both patient subsets; and the 5-year OS rates were 100% and 91.7% for the intermediate- and high-risk patients, respectively. The Gleason score (<8 vs. ≥8) was significant for the 5-year PSA relapse-free survival on multivariate analysis (p = 0.044). There was no grade 3 or 4 acute toxicity. The incidence of

Portal placement in elbow arthroscopy by novice surgeons: cadaver study.

Science.gov (United States)

Claessen, Femke M A P; Kachooei, Amir R; Kolovich, Gregory P; Buijze, Geert A; Oh, Luke S; van den Bekerom, Michel P J; Doornberg, Job N

2017-07-01

In this anatomical cadaver study, the distance between major nerves and ligaments at risk for injury and portal sites created by trainees was measured. Trainees, inexperienced in elbow arthroscopy, have received a didactic lecture and cadaver instruction prior to portal placement. The incidence of iatrogenic injury from novice portal placement was also determined. Anterolateral, direct lateral, and anteromedial arthroscopic portals were created in ten cadavers by ten inexperienced trainees in elbow arthroscopy. After creating each portal, the trajectory of the portal was marked with a guide pin. Subsequently, the cadavers were dissected and the distances between the guide pin in the anterolateral, direct lateral, and anteromedial portals and important ligaments and nerves were measured. The difference between the distance of the direct lateral portal and the posterior antebrachial cutaneous nerve (PABCN) (22 mm, p cadaver instruction session alone. Level of evidence V.

Alternative fiducial markers for Vero real-time tumor tracking radiotherapy: A phantom study

Science.gov (United States)

Park, Shin-Hyung; Kim, Jae-Chul; Kim, Sung Joon

2016-12-01

The objective of this study was to investigate the feasibility of potential fiducial markers consisting of various materials in a Vero real-time tumor-tracking (RTTT) system. In order to determine the applicability of fiducial markers for the Vero RTTT system, we tested various markers consisting of 8 kinds of material (titanium, stainless steel, high-carbon steel, pure steel, copper, silver, tantalum, and gold) with various diameters ranging from 0.3 mm to 1.6 mm and a length of 5 mm. Additionally, a commercial gold coil marker (Visicoil™, IBA dosimetry, Schwarzenbruck, Germany) of diameter 0.5 mm and length 1 cm was included for evaluation. The radiologic visibility on kV fluoroscopy/kV CT scan images of the fiducial markers was evaluated. The detectability on the RTTT system was tested using a two-dimensional moving phantom (Brainlab AG, Feldkirchen, Germany), producing sinusoidal motion. The target center's accuracy was evaluated by calculating the deviation of the position of a metal sphere from the center on the dose profile. Dose profiles were measured using Gafchromic EBT2 films (International Specialty Products, NJ, USA). All markers were visible on kV fluoroscopy/kV CT while markers with atomic number ≥ 25.7 were detectable on the Vero RTTT system. All the detected markers showed excellent geometric accuracy.

Daily online localization using implanted fiducial markers and its impact on planning target volume for carcinoma prostate.

Science.gov (United States)

Khosa, Robin; Nangia, Sapna; Chufal, Kundan S; Ghosh, D; Kaul, Rakesh; Sharma, Lalit

2010-01-01

Aim of the study was to assess prostate motion on daily basis with respect to setup and to compare the shifts based on bony anatomy and gold fiducial markers. Gold fiducial markers were inserted in prostate under U/S guidance and daily portal images were taken and compared with digitally reconstructed images, both using bony landmarks and fiducial markers as reference. A dose of 2 MU was given for two orthogonal images daily. The mean and standard deviation of displacement using gold seeds and bone were calculated. Systematic and random errors were generated. The planning target volume (PTV) was calculated using the Van Herk formula. A total of 180 portal images from 10 patients were studied. The mean displacement along x, y and z axes was 1.67 mm, 3.58 mm, and 1.76 mm using fiducial markers and 2.12 mm, 3.47 mm, and 2.09 mm using bony landmarks, respectively. The mean internal organ motion was 1.23 mm (+1.45), 3.11 mm (+2.69 mm); and 1.87 mm (+1.67 mm) along x, y and z axes, respectively. The PTV to account for prostate motion if daily matching was not done was 4.64 mm, 10.41 mm and 4.40 mm along lateral, superoinferior, and anteroposterior directions, respectively. If bony landmarks were used for daily matching, margins of 3.61 mm, 7.31 mm, and 4.72 mm in lateral, superoinferior, and anteroposterior directions should be added to the clinical target volume. Daily alignment using gold fiducial markers is an effective method of localizing prostate displacement. It provides the option of reducing margins, thus limiting normal tissue toxicity and allowing the possibility of dose escalation for better long-term control.

Utility of core biopsy with concurrent ROSE FNA in the diagnosis of pancreatic tumor-does the biopsy add any diagnostic benefit?

Science.gov (United States)

Yan, Lei; Ikemura, Kenji; Park, Ji-Weon

2018-02-01

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) and endoscopic ultrasound-guided core-needle biopsy (EUS-CNB) are widely used for diagnosis of pancreatic tumors. The aim of our study was to compare the diagnostic performance of ROSE EUS-FNA and EUS-CNB for diagnosis of pancreatic malignancy during the same EUS. Patients who underwent both FNA and CNB during the same EUS for pancreatic solid lesion were reviewed retrospectively. Sample adequacy, diagnostic yield (defined as percentage of definitive diagnosis), sensitivity and specificity for malignancy were compared between FNA and CNB. A total of 48 patients with solid pancreatic lesions were evaluated. The proportions of adequate samples were 48/48 (100%) for FNA and 45/48 (93.7%) for core biopsy (P = .24). The diagnostic yield was 42/48 (87.5%) and 33/48 (68.7%) for FNA and CNB respectively (P = .046). The incremental increase in diagnostic yield by combining both methods was 2/48 (4%). The diagnostic yield for malignancy was 30/32 (93.7%) for FNA and 23/32 (71.8%) for CNB (P = .043). The sensitivity for the diagnosis of malignancy for FNA and CNB were 90.6% and 69%, respectively (P = .045). The specificity was 100% for both methods. The sensitivity for diagnosing malignancy increased to 93.8% when the two methods were combined. The difference in diagnostic yield was not associated with lesion size or location. EUS-guided FNA is a superior method of assessing solid pancreatic lesion and pancreatic malignancy with better diagnostic yield and higher sensitivity than EUS-CNB. © 2017 Wiley Periodicals, Inc.

A review of longitudinal community and hospital placements in medical education: BEME Guide No. 26.

Science.gov (United States)

Thistlethwaite, J E; Bartle, Emma; Chong, Amy Ai Ling; Dick, Marie-Louise; King, David; Mahoney, Sarah; Papinczak, Tracey; Tucker, George

2013-08-01

Traditionally, clinical learning for medical students consists of short-term and opportunistic encounters with primarily acute-care patients, supervised by an array of clinician preceptors. In response to educational concerns, some medical schools have developed longitudinal placements rather than short-term rotations. Many of these longitudinal placements are also integrated across the core clinical disciplines, are commonly termed longitudinal integrated clerkships (LICs) and often situated in rural locations. This review aimed to explore, analyse and synthesise evidence relating to the effectiveness of longitudinal placements, for medical students in particular to determine which aspects are most critical to successful outcomes. Extensive search of the literature resulted in 1679 papers and abstracts being considered, with 53 papers ultimately being included for review. The review group coded these 53 papers according to standard BEME review guidelines. Specific information extracted included: data relating to effectiveness, the location of the study, number of students involved, format, length and description of placement, the learning outcomes, research design, the impact level for evaluation and the main evaluation methods and findings. We applied a realist approach to consider what works well for whom and under what circumstances. The early LICs were all community-based immersion programs, situated in general practice and predominantly in rural settings. More recent LIC innovations were situated in tertiary-level specialist ambulatory care in urban settings. Not all placements were integrated across medical disciplines but were longitudinal in relation to location, patient base and/or supervision. Twenty-four papers focussed on one of four programs from different viewpoints. Most evaluations were student opinion (survey, interview, focus group) and/or student assessment results. Placements varied from one half day per week for six months through to full time

USES 2.0, The Uniform System for the Evaluation of Substances, version 2.0 ; supplement to EUSES

OpenAIRE

Linders JBHJ; Jager DT (eds.); CSR; ECO

1997-01-01

This interim report describes the updated risk assessment system for agricultural and non-agricultural pesticides. It will be integrated with the European Union System for the Evaluation of Substances, EUSES 1.0, into USES 2.0, the second version of the Uniform System for the Evaluation of Substances. The report is primarily made as preparation to the programming and testing of USES 2.0.

Comparison of prostate set-up accuracy and margins with off-line bony anatomy corrections and online implanted fiducial-based corrections.

Science.gov (United States)

Greer, P B; Dahl, K; Ebert, M A; Wratten, C; White, M; Denham, J W

2008-10-01

The aim of the study was to determine prostate set-up accuracy and set-up margins with off-line bony anatomy-based imaging protocols, compared with online implanted fiducial marker-based imaging with daily corrections. Eleven patients were treated with implanted prostate fiducial markers and online set-up corrections. Pretreatment orthogonal electronic portal images were acquired to determine couch shifts and verification images were acquired during treatment to measure residual set-up error. The prostate set-up errors that would result from skin marker set-up, off-line bony anatomy-based protocols and online fiducial marker-based corrections were determined. Set-up margins were calculated for each set-up technique using the percentage of encompassed isocentres and a margin recipe. The prostate systematic set-up errors in the medial-lateral, superior-inferior and anterior-posterior directions for skin marker set-up were 2.2, 3.6 and 4.5 mm (1 standard deviation). For our bony anatomy-based off-line protocol the prostate systematic set-up errors were 1.6, 2.5 and 4.4 mm. For the online fiducial based set-up the results were 0.5, 1.4 and 1.4 mm. A prostate systematic error of 10.2 mm was uncorrected by the off-line bone protocol in one patient. Set-up margins calculated to encompass 98% of prostate set-up shifts were 11-14 mm with bone off-line set-up and 4-7 mm with online fiducial markers. Margins from the van Herk margin recipe were generally 1-2 mm smaller. Bony anatomy-based set-up protocols improve the group prostate set-up error compared with skin marks; however, large prostate systematic errors can remain undetected or systematic errors increased for individual patients. The margin required for set-up errors was found to be 10-15 mm unless implanted fiducial markers are available for treatment guidance.

In Vivo Tooth-Supported Implant Surgical Guides Fabricated With Desktop Stereolithographic Printers: Fully Guided Surgery Is More Accurate Than Partially Guided Surgery.

Science.gov (United States)

Bencharit, Sompop; Staffen, Adam; Yeung, Matthew; Whitley, Daniel; Laskin, Daniel M; Deeb, George R

2018-02-21

Desktop stereolithographic printers combined with intraoral scanning and implant planning software promise precise and cost-effective guided implant surgery. The purpose of the present study was to determine the overall range of accuracy of tooth-supported guided implant surgery using desktop printed stereolithographic guides. A cross-sectional study comparing fully and partially guided implant surgery was conducted. Preoperative cone beam computed tomography (CBCT) and intraoral scans were used to plan the implant sites. Surgical guides were then fabricated using a desktop stereolithographic 3-dimensional printer. Postoperative CBCT was used to evaluate the accuracy of placement. Deviations from the planned positions were used as the primary outcome variables. The planning software used, implant systems, and anterior/posterior positions were the secondary outcome variables. The differences between the planned and actual implant positions in the mesial, distal, buccal, and lingual dimensions and buccolingual angulations were determined, and the accuracy was compared statistically using the 1-tail F-test (P = .01), box plots, and 95% confidence intervals for the mean. Sixteen partially edentulous patients requiring placement of 31 implants were included in the present study. The implant deviations from the planned positions for mesial, distal, buccal, and lingual dimensions and buccolingual angulations with the fully guided protocol (n = 20) were 0.17 ± 0.78 mm, 0.44 ± 0.78 mm, 0.23 ± 1.08 mm, -0.22 ± 1.44 mm, and -0.32° ± 2.36°, respectively. The corresponding implant deviations for the partially guided protocol (n = 11) were 0.33 ± 1.38 mm, -0.03 ± 1.59 mm, 0.62 ± 1.15 mm, -0.27 ± 1.61 mm, and 0.59° ± 6.83°. The difference between the variances for fully and partially guided surgery for the distal and angulation dimensions was statistically significant (P = .006 and P guided implant surgery is more accurate than

Diagnostic Yield and Safety of Endoscopic Ultrasound Guided Fine Needle Aspiration of Central Mediastinal Lung Masses

Directory of Open Access Journals (Sweden)

Enrique Vazquez-Sequeiros

2013-01-01

Full Text Available Background and Aims. EUS-FNA is an accurate and safe technique to biopsy mediastinal lymph nodes. However, there are few data pertaining to the role of EUS-FNA to biopsy central lung masses. The aim of the study was to assess the diagnostic yield and safety of EUS-FNA of indeterminate central mediastinal lung masses. Methods. Design: Retrospective review of a prospectively maintained database; noncomparative. Setting: Tertiary referral center. From 10/2004 to 12/2010, all patients with a lung mass located within proximity to the esophagus were referred for EUS-FNA. Main Outcome Measurement: EUS-FNA diagnostic accuracy and safety. Results. 73 consecutive patients were included. EUS allowed detection in 62 (85% patients with lack of visualization prohibiting FNA in 11 patients. Among sampled lesions, one patient (1/62 = 1.6% had a benign lung mass (hamartoma, while the remaining 61 patients (61/62 = 98.4% had a malignant mass (primary lung cancer: 55/61 = 90%; lung metastasis: 6/61 = 10%. The sensitivity, specificity, and accuracy of EUS-FNA were 96.7%, 100%, and 96.7%, respectively. The sensitivity was 80.8% when considering nonvisualized masses. One patient developed a pneumothorax (1/62 = 1.6%. Conclusions. EUS-FNA appears to be an accurate and safe technique for tissue diagnosis of central mediastinal lung masses.

First magnetic resonance imaging-guided aortic stenting and cava filter placement using a polyetheretherketone-based magnetic resonance imaging-compatible guidewire in swine: proof of concept.

Science.gov (United States)

Kos, Sebastian; Huegli, Rolf; Hofmann, Eugen; Quick, Harald H; Kuehl, Hilmar; Aker, Stephanie; Kaiser, Gernot M; Borm, Paul J A; Jacob, Augustinus L; Bilecen, Deniz

2009-05-01

The purpose of this study was to demonstrate feasibility of percutaneous transluminal aortic stenting and cava filter placement under magnetic resonance imaging (MRI) guidance exclusively using a polyetheretherketone (PEEK)-based MRI-compatible guidewire. Percutaneous transluminal aortic stenting and cava filter placement were performed in 3 domestic swine. Procedures were performed under MRI-guidance in an open-bore 1.5-T scanner. The applied 0.035-inch guidewire has a PEEK core reinforced by fibres, floppy tip, hydrophilic coating, and paramagnetic markings for passive visualization. Through an 11F sheath, the guidewire was advanced into the abdominal (swine 1) or thoracic aorta (swine 2), and the stents were deployed. The guidewire was advanced into the inferior vena cava (swine 3), and the cava filter was deployed. Postmortem autopsy was performed. Procedural success, guidewire visibility, pushability, and stent support were qualitatively assessed by consensus. Procedure times were documented. Guidewire guidance into the abdominal and thoracic aortas and the inferior vena cava was successful. Stent deployments were successful in the abdominal (swine 1) and thoracic (swine 2) segments of the descending aorta. Cava filter positioning and deployment was successful. Autopsy documented good stent and filter positioning. Guidewire visibility through applied markers was rated acceptable for aortic stenting and good for venous filter placement. Steerability, pushability, and device support were good. The PEEK-based guidewire allows either percutaneous MRI-guided aortic stenting in the thoracic and abdominal segments of the descending aorta and filter placement in the inferior vena cava with acceptable to good device visibility and offers good steerability, pushability, and device support.

First Magnetic Resonance Imaging-Guided Aortic Stenting and Cava Filter Placement Using a Polyetheretherketone-Based Magnetic Resonance Imaging-Compatible Guidewire in Swine: Proof of Concept

International Nuclear Information System (INIS)

Kos, Sebastian; Huegli, Rolf; Hofmann, Eugen; Quick, Harald H.; Kuehl, Hilmar; Aker, Stephanie; Kaiser, Gernot M.; Borm, Paul J. A.; Jacob, Augustinus L.; Bilecen, Deniz

2009-01-01

The purpose of this study was to demonstrate feasibility of percutaneous transluminal aortic stenting and cava filter placement under magnetic resonance imaging (MRI) guidance exclusively using a polyetheretherketone (PEEK)-based MRI-compatible guidewire. Percutaneous transluminal aortic stenting and cava filter placement were performed in 3 domestic swine. Procedures were performed under MRI-guidance in an open-bore 1.5-T scanner. The applied 0.035-inch guidewire has a PEEK core reinforced by fibres, floppy tip, hydrophilic coating, and paramagnetic markings for passive visualization. Through an 11F sheath, the guidewire was advanced into the abdominal (swine 1) or thoracic aorta (swine 2), and the stents were deployed. The guidewire was advanced into the inferior vena cava (swine 3), and the cava filter was deployed. Postmortem autopsy was performed. Procedural success, guidewire visibility, pushability, and stent support were qualitatively assessed by consensus. Procedure times were documented. Guidewire guidance into the abdominal and thoracic aortas and the inferior vena cava was successful. Stent deployments were successful in the abdominal (swine 1) and thoracic (swine 2) segments of the descending aorta. Cava filter positioning and deployment was successful. Autopsy documented good stent and filter positioning. Guidewire visibility through applied markers was rated acceptable for aortic stenting and good for venous filter placement. Steerability, pushability, and device support were good. The PEEK-based guidewire allows either percutaneous MRI-guided aortic stenting in the thoracic and abdominal segments of the descending aorta and filter placement in the inferior vena cava with acceptable to good device visibility and offers good steerability, pushability, and device support.

Creating a distortion characterisation dataset for visual band cameras using fiducial markers

CSIR Research Space (South Africa)

Jermy, R

2015-11-01

Full Text Available . This will allow other researchers to perform the same steps and create better algorithms to accurately locate fiducial markers and calibrate cameras. A second dataset that can be used to assess the accuracy of the stereo vision of two calibrated cameras is also...

Optimization in multi-implant placement for immediate loading in edentulous arches using a modified surgical template and prototyping: a case report.

Science.gov (United States)

Jayme, Sérgio J; Muglia, Valdir A; de Oliveira, Rafael R; Novaes, Arthur B Júnior

2008-01-01

Immediate loading of dental implants shortens the treatment time and makes it possible to give the patient an esthetic appearance throughout the treatment period. Placement of dental implants requires precise planning that accounts for anatomic limitations and restorative goals. Diagnosis can be made with the assistance of computerized tomographic scanning, but transfer of planning to the surgical field is limited. Recently, novel CAD/CAM techniques such as stereolithographic rapid prototyping have been developed to build surgical guides in an attempt to improve precision of implant placement. The aim of this case report was to show a modified surgical template used throughout implant placement as an alternative to a conventional surgical guide.

Conformal radiotherapy for prostate cancer: contribution of pelvic immobilization and new fiducial markers

International Nuclear Information System (INIS)

Garcia, R.; Oozeer, R.; Le Thanh, H.; Chauvet, B.; Toy, B.J.; Reboul, F.

1997-01-01

To reduce errors in the positioning of patients treated with external conformal radiotherapy for prostate cancer, we evaluated both the use of an immobilization device and new fiducial markers. The immobilization device consisted of an individual mold made of polyurethane foam. Two sets of skin markers located on the anterior tibial surfaces were used to identify the pelvic isocenter. The patient's position was evaluated by orthogonal port film which were then compared with the original simulation film. Results are presented with respect to orthogonal axes. Comparison with classic procedures without immobilization showed that use of the mold and new fiducial markers led to a decrease in set-up errors which were less than 5 mm. With the use of an immobilization device and optimized techniques for patients' positioning, conformal radiotherapy of prostate cancer is more accurate. (authors)

Percutaneous transluminal angioplasty and stent placement for iliofemoral arterial atherosclerotic occlusive disease

International Nuclear Information System (INIS)

Zheng Yanbo; Jiang Wenjin; Liu Sheng; Song Xuepeng; Sheng Qirui

2006-01-01

Objectives: To assess the safety and efficacy of percutaneous transluminal angioplasty (PTA) and stent placement for the treatment of iliofemoral arterial atherosclerotic occlusive diseases. Methods From April 1999 to August 2004, 13 cases of iliofemoral arterial occlusions were recanalized with contact thrombolytic therapy combined with guide wire mechanical recanalization method, followed by angioplasty and stent placement. A total of 25 self-expanding Wallstents were deployed. All patients were followed up by means of duplex ultrasound, angiography, or both. Results: All 13 cases were successfully recanalized, with technical successful rate of 100%. Available follow-up for all patients from 8 months-5 years (mean 26.2 months) included one patient undergoing again with successful contact thrombolysis because of early thrombosis; another patient with recurrent symptoms at 19 month after operation undertaking surgical bypass because of later reocclusion; all of the rest stents showing patency by the end of the study. Conclusions: Contact thrombolysis combined with guide wire mechanical recanalization for iliofemoral arterial occlusion is safe and effective, whereas PTA and stent placement would have the nearly same efficacy for the disease with mild injury and low restenosis. (authors)

Harmonic Contrast-Enhanced Endoscopic Ultrasonography for the Guidance of Fine-Needle Aspiration in Solid Pancreatic Masses

DEFF Research Database (Denmark)

Seicean, A; Badea, R; Moldovan-Pop, A

2015-01-01

Purpose: The global accuracy of fine-needle aspiration guided by endoscopic ultrasound (EUS-FNA) for pancreatic adenocarcinoma is about 85 %. The use of contrast agents during EUS to highlight vessels and the necrotic parts of pancreatic masses may improve biopsy guidance. Our aim was to assess...... whether the guidance of FNA by harmonic contrast-enhanced endoscopic ultrasound (CH-EUS) would increase diagnostic accuracy relative to conventional EUS-FNA in the same pancreatic masses. Patients and Methods: In a prospective study, EUS-FNA was performed in patients with pancreatic masses on CT scan......, followed by harmonic CH-EUS using SonoVue. A second cluster of CH-EUS-FNA was performed on contrast-enhanced images. The final diagnosis was based on the results of EUS-FNA and surgery, or the findings after 12 months' follow-up. Results: The final diagnosis was adenocarcinoma (n = 35), chronic...

SU-F-J-137: Intrafractional Change of the Relationship Between Internal Fiducials and External Breathing Signal in Pancreatic Cancer Stereotactic Body Radiation Therapy

Energy Technology Data Exchange (ETDEWEB)

Pettersson, N; Murphy, J; Simpson, D; Cervino, L [University of California, San Diego, La Jolla, CA (United States)

2016-06-15

Purpose: The use of respiratory gating for management of breathing motion during stereotactic body radiation therapy (SBRT) relies on a consistent relationship between the breathing signal and the actual position of the internal target. This relationship was investigated in patients treated for pancreatic cancer. Methods: Four patients with pancreatic cancer undergoing SBRT that had implanted fiducials in the tumor were included in this study. Treatment plans were generated based on the exhale phases (30–70%) from the pre-treatment 4DCT. The margin between the internal target volume (ITV) and the planning target volume was three mm. After patient setup using cone-beam CT, simultaneous fluoroscopic imaging and breathing motion monitoring were used during at least three breathing cycles to verify the fiducial position and to optimize the gating window. After treatment, fluoroscopic images were acquired for verification purposes and exported for retrospective analyses. Fiducial positions were determined using a template-matching algorithm. For each dataset, we established a linear relationship between the fiducial position and the anterior-posterior (AP) breathing signal. The relationships before and after treatment were compared and the dose distribution impact evaluated. Results: Seven pre- and post-treatment fluoroscopic pairs were available for fiducial position analyses in the superior-inferior (SI) and left-right (LR) directions, and five in the AP direction. Time between image acquisitions was typically six to eight minutes. An average absolute change of 1.2±0.7 mm (range: 0.1–1.7) of the SI fiducial position relative to the external signal was found. Corresponding numbers for the LR and AP fiducial positions were 0.9±1.0 mm (range: 0.2–3.0) and 0.5±0.4 mm (range: 0.2–1.2), respectively. The dose distribution impact was small in both the ITV and organs-at-risk. Conclusion: The relationship change between fiducial position and external breathing

SU-F-J-137: Intrafractional Change of the Relationship Between Internal Fiducials and External Breathing Signal in Pancreatic Cancer Stereotactic Body Radiation Therapy

International Nuclear Information System (INIS)

Pettersson, N; Murphy, J; Simpson, D; Cervino, L

2016-01-01

Purpose: The use of respiratory gating for management of breathing motion during stereotactic body radiation therapy (SBRT) relies on a consistent relationship between the breathing signal and the actual position of the internal target. This relationship was investigated in patients treated for pancreatic cancer. Methods: Four patients with pancreatic cancer undergoing SBRT that had implanted fiducials in the tumor were included in this study. Treatment plans were generated based on the exhale phases (30–70%) from the pre-treatment 4DCT. The margin between the internal target volume (ITV) and the planning target volume was three mm. After patient setup using cone-beam CT, simultaneous fluoroscopic imaging and breathing motion monitoring were used during at least three breathing cycles to verify the fiducial position and to optimize the gating window. After treatment, fluoroscopic images were acquired for verification purposes and exported for retrospective analyses. Fiducial positions were determined using a template-matching algorithm. For each dataset, we established a linear relationship between the fiducial position and the anterior-posterior (AP) breathing signal. The relationships before and after treatment were compared and the dose distribution impact evaluated. Results: Seven pre- and post-treatment fluoroscopic pairs were available for fiducial position analyses in the superior-inferior (SI) and left-right (LR) directions, and five in the AP direction. Time between image acquisitions was typically six to eight minutes. An average absolute change of 1.2±0.7 mm (range: 0.1–1.7) of the SI fiducial position relative to the external signal was found. Corresponding numbers for the LR and AP fiducial positions were 0.9±1.0 mm (range: 0.2–3.0) and 0.5±0.4 mm (range: 0.2–1.2), respectively. The dose distribution impact was small in both the ITV and organs-at-risk. Conclusion: The relationship change between fiducial position and external breathing

Development and Implementation of an Ultrasound-Guided Peripheral Intravenous Catheter Program for Emergency Nurses.

Science.gov (United States)

Edwards, Courtney; Jones, Jodi

2018-01-01

Emergency medical care often necessitates placement of peripheral intravenous (PIV) catheters. When traditional methods for obtaining PIV access are not successful, ultrasound guidance is a rescue technique for peripheral vascular placement that improves the quality of patient care. The aim of this training program was to develop a process where emergency nurses would be competent to perform ultrasound guided PIV to improve the quality of patient care delivered while reducing throughput time. Administrative program development required creating a nursing practice statement, procedure guideline, operational plan, and competency validation. A training program comprising both didactic and hands-on training was developed and provided by emergency medicine physicians with formal ultrasound fellowship training. In determining whether the training program was adequate in preparing the student to place an ultrasound-guided PIV, 92.9% of students "agreed" or "strongly agreed." In having confidence in their ability to obtain an ultrasound guided PIV catheter placement, 35.7% of respondents "agreed" and 64.3% "strongly agreed." In finding it difficult to be successful in achieving ultrasound guided PIV catheter placement, 71.4% of students "strongly disagreed" and 14.3% "disagreed." All students (100%) felt it was a feasible task to train nurses to successfully place ultrasound-guided PIV catheters and 71.4% of students strongly support continuing to provide this training program and competency validation. Establishment of an effective didactic and hands-on training program resulted in emergency department nurses becoming competent in placement of ultrasound guided PIV catheters to provide optimal patient care. Copyright © 2017 Emergency Nurses Association. Published by Elsevier Inc. All rights reserved.

Clinical outcome of fiducial-less CyberKnife radiosurgery for stage I non-small cell lung cancer

International Nuclear Information System (INIS)

Jung, In Hye; Song, Si Yeol; Cho, Byung Chul; Kwak, Jung Won; Jung, Nuri Hyun; Kim, Su Ssan; Choi, Eun Kyung; Jung, Jin Hong; Je, Hyoung Uk; Choi, Won Sik

2015-01-01

To evaluate the treatment results in early stage non-small cell lung cancer patients who have undergone fiducial-less CyberKnife radiosurgery (CKRS). From June 2011 to November 2013, 58 patients underwent CKRS at Asan Medical Center for stage I lung cancer. After excluding 14 patients, we retrospectively reviewed the records of the remaining 44 patients. All analyses were performed using SPSS ver. 21. The median age at diagnosis was 75 years. Most patients had inoperable primary lung cancer with a poor pulmonary function test with comorbidity or old age. The clinical stage was IA in 30 patients (68.2%), IB in 14 (31.8%). The mean tumor size was 2.6 cm (range, 1.2 to 4.8 cm), and the tumor was smaller than 2 cm in 12 patients (27.3%). The radiation dose given was 48-60 Gy in 3-4 fractions. In a median follow-up of 23.1 months, local recurrence occurred in three patients (2-year local recurrence-free survival rate, 90.4%) and distant metastasis occurred in 13 patients. All patients tolerated the radiosurgery well, only two patients developing grade 3 dyspnea. The most common complications were radiation-induced fibrosis and pneumonitis. Eight patients died due to cancer progression. The results showed that fiducial-less CKRS shows comparable local tumor control and survival rates to those of LINAC-based SABR or CKRS with a fiducial marker. Thus, fiducial-less CKRS using Xsight lung tracking system can be effectively and safely performed for patients with medically inoperable stage I non-small cell lung cancer without any risk of procedure-related complication

Clinical outcome of fiducial-less CyberKnife radiosurgery for stage I non-small cell lung cancer

Energy Technology Data Exchange (ETDEWEB)

Jung, In Hye; Song, Si Yeol; Cho, Byung Chul; Kwak, Jung Won; Jung, Nuri Hyun; Kim, Su Ssan; Choi, Eun Kyung [Dept. of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Jung, Jin Hong [Dept. of Radiation Oncology, Kyung Hee University Medical Center, Kyung Hee University School of Medicine, Seoul (Korea, Republic of); Je, Hyoung Uk [Dept. of Radiation Oncology, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan (Korea, Republic of); Choi, Won Sik [Dept. of Radiation Oncology, Gangneung Asan Hospital, Uiversity of Ulsan College of Medicine, Gangneung (Korea, Republic of)

2015-06-15

To evaluate the treatment results in early stage non-small cell lung cancer patients who have undergone fiducial-less CyberKnife radiosurgery (CKRS). From June 2011 to November 2013, 58 patients underwent CKRS at Asan Medical Center for stage I lung cancer. After excluding 14 patients, we retrospectively reviewed the records of the remaining 44 patients. All analyses were performed using SPSS ver. 21. The median age at diagnosis was 75 years. Most patients had inoperable primary lung cancer with a poor pulmonary function test with comorbidity or old age. The clinical stage was IA in 30 patients (68.2%), IB in 14 (31.8%). The mean tumor size was 2.6 cm (range, 1.2 to 4.8 cm), and the tumor was smaller than 2 cm in 12 patients (27.3%). The radiation dose given was 48-60 Gy in 3-4 fractions. In a median follow-up of 23.1 months, local recurrence occurred in three patients (2-year local recurrence-free survival rate, 90.4%) and distant metastasis occurred in 13 patients. All patients tolerated the radiosurgery well, only two patients developing grade 3 dyspnea. The most common complications were radiation-induced fibrosis and pneumonitis. Eight patients died due to cancer progression. The results showed that fiducial-less CKRS shows comparable local tumor control and survival rates to those of LINAC-based SABR or CKRS with a fiducial marker. Thus, fiducial-less CKRS using Xsight lung tracking system can be effectively and safely performed for patients with medically inoperable stage I non-small cell lung cancer without any risk of procedure-related complication.

Hawking, fiducial, and free-fall temperature of black hole on gravity's rainbow

Energy Technology Data Exchange (ETDEWEB)

Gim, Yongwan; Kim, Wontae [Sogang University, Department of Physics, Seoul (Korea, Republic of)

2016-03-15

On gravity's rainbow, the energy of test particles deforms the geometry of a black hole in such a way that the corresponding Hawking temperature is expected to be modified. It means that the fiducial and free-fall temperatures on the black hole background should also be modified according to deformation of the geometry. In this work, the probing energy of test particles is assumed as the average energy of the Hawking particle in order to study the particle back reaction of the geometry by using the advantage of gravity's rainbow. We shall obtain the modified fiducial and free-fall temperatures, respectively. The behaviors of these two temperatures on the horizon tell us that black hole complementarity is still well defined on gravity's rainbow. (orig.)

Generalized Confidence Intervals and Fiducial Intervals for Some Epidemiological Measures

Directory of Open Access Journals (Sweden)

Ionut Bebu

2016-06-01

Full Text Available For binary outcome data from epidemiological studies, this article investigates the interval estimation of several measures of interest in the absence or presence of categorical covariates. When covariates are present, the logistic regression model as well as the log-binomial model are investigated. The measures considered include the common odds ratio (OR from several studies, the number needed to treat (NNT, and the prevalence ratio. For each parameter, confidence intervals are constructed using the concepts of generalized pivotal quantities and fiducial quantities. Numerical results show that the confidence intervals so obtained exhibit satisfactory performance in terms of maintaining the coverage probabilities even when the sample sizes are not large. An appealing feature of the proposed solutions is that they are not based on maximization of the likelihood, and hence are free from convergence issues associated with the numerical calculation of the maximum likelihood estimators, especially in the context of the log-binomial model. The results are illustrated with a number of examples. The overall conclusion is that the proposed methodologies based on generalized pivotal quantities and fiducial quantities provide an accurate and unified approach for the interval estimation of the various epidemiological measures in the context of binary outcome data with or without covariates.

Solid Pseudopapillary Neoplasm of the Pancreas in Young Male Patients: Three Case Reports

Directory of Open Access Journals (Sweden)

Akira Aso

2017-01-01

Full Text Available A preoperative diagnosis of solid pseudopapillary neoplasms (SPNs in young male patients is difficult to achieve using radiological images. We herein present three cases of young male patients with relatively small SPNs. Endoscopic ultrasound (EUS showed well-encapsulated, smooth-surfaced, heterogeneous solid lesions in all patients, and all preoperative diagnoses were achieved by EUS-guided fine needle aspiration (EUS-FNA. The final pathological diagnosis after surgery was an SPN with a Ki-67 labeling index of <2%. SPNs should be considered even in young male patients. EUS with EUS-FNA could be a useful diagnostic modality for SPNs even in young male patients.

Daily online bony correction is required for prostate patients without fiducial markers or soft-tissue imaging.

Science.gov (United States)

Johnston, M L; Vial, P; Wiltshire, K L; Bell, L J; Blome, S; Kerestes, Z; Morgan, G W; O'Driscoll, D; Shakespeare, T P; Eade, T N

2011-09-01

To compare online position verification strategies with offline correction protocols for patients undergoing definitive prostate radiotherapy. We analysed 50 patients with implanted fiducial markers undergoing curative prostate radiation treatment, all of whom underwent daily kilovoltage imaging using an on-board imager. For each treatment, patients were set-up initially with skin tattoos and in-room lasers. Orthogonal on-board imager images were acquired and the couch shift to match both bony anatomy and the fiducial markers recorded. The set-up error using skin tattoos and offline bone correction was compared with online bone correction. The fiducial markers were used as the reference. Data from 1923 fractions were analysed. The systematic error was ≤1 mm for all protocols. The average random error was 2-3mm for online bony correction and 3-5mm for skin tattoos or offline-bone. Online-bone showed a significant improvement compared with offline-bone in the number of patients with >5mm set-up errors for >10% (P20% (Pmarkers or daily soft-tissue imaging. Copyright © 2011 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

Comparison of prostate set-up accuracy and margins with off-line bony anatomy corrections and online implanted fiducial-based corrections

International Nuclear Information System (INIS)

Greer, P. B.; Dahl, K.; Ebert, M. A.; Wratten, C.; White, M.; Denham, K. W.

2008-01-01

Full text: The aim of the study was to determine prostate set-up accuracy and set-up margins with off-line bony anatomy-based imaging protocols, compared with online implanted fiducial marker-based imaging with daily corrections. Eleven patients were treated with implanted prostate fiducial markers and online set-up corrections. Pretreatment orthogonal electronic portal images were acquired to determine couch shifts and verification images were acquired during treatment to measure residual set-up error. The prostate set-up errors that would result from skin marker set-up, off-line bony anatomy-based protocols and online fiducial marker-based corrections were determined. Set-up margins were calculated for each set-up technique using the percentage of encompassed isocentres land a margin recipe. The prostate systematic set-up errors in the medial-lateral, superior-inferior and anterior-I posterior directions for skin marker set-up were 2.2, 3.6 and 4.5 mm (1 standard deviation). For our bony anatomy-I based off-line protocol the prostate systematic set-up errors were 1.6, 2.5 and 4.4 mm. For the online fiducial based set-up the results were 0.5, 1.4 and 1.4 mm. A prostate systematic error of 10.2 mm was uncorrected by the off-line bone protocol in one patient. Set-up margins calculated to encompass 98% of prostate set-up shifts were 111-14 mm with bone off-line set-up and 4-7 mm with online fiducial markers. Margins from the van Herk margin I recipe were generally 1-2 mm smaller. Bony anatomy-based set-up protocols improve the group prostate set-up error compared with skin marks; however, large prostate systematic errors can remain undetected or systematic (errors increased for individual patients. The margin required for set-up errors was found to be 10-15 mm unless I implanted fiducial markers are available for treatment guidance.

Endoscopic ultrasound elastography for evaluation of lymph nodes and pancreatic masses: a multicenter study

DEFF Research Database (Denmark)

Giovannini, Marc; Thomas, Botelberge; Erwan, Bories

2009-01-01

AIM: To evaluate the ability of endoscopic ultrasound (EUS) elastography to distinguish benign from malignant pancreatic masses and lymph nodes. METHODS: A multicenter study was conducted and included 222 patients who underwent EUS examination with assessment of a pancreatic mass (n = 121) or lymph...... node (n = 101). The classification as benign or malignant, based on the real time elastography pattern, was compared with the classification based on the B-mode EUS images and with the final diagnosis obtained by EUS-guided fine needle aspiration (EUS-FNA) and/or by surgical pathology. An interobserver...... study was performed. RESULTS: The sensitivity and specificity of EUS elastography to differentiate benign from malignant pancreatic lesions are 92.3% and 80.0%, respectively, compared to 92.3% and 68.9%, respectively, for the conventional B-mode images. The sensitivity and specificity of EUS...

Technical Note: Error metrics for estimating the accuracy of needle/instrument placement during transperineal magnetic resonance/ultrasound-guided prostate interventions.

Science.gov (United States)

Bonmati, Ester; Hu, Yipeng; Villarini, Barbara; Rodell, Rachael; Martin, Paul; Han, Lianghao; Donaldson, Ian; Ahmed, Hashim U; Moore, Caroline M; Emberton, Mark; Barratt, Dean C

2018-04-01

Image-guided systems that fuse magnetic resonance imaging (MRI) with three-dimensional (3D) ultrasound (US) images for performing targeted prostate needle biopsy and minimally invasive treatments for prostate cancer are of increasing clinical interest. To date, a wide range of different accuracy estimation procedures and error metrics have been reported, which makes comparing the performance of different systems difficult. A set of nine measures are presented to assess the accuracy of MRI-US image registration, needle positioning, needle guidance, and overall system error, with the aim of providing a methodology for estimating the accuracy of instrument placement using a MR/US-guided transperineal approach. Using the SmartTarget fusion system, an MRI-US image alignment error was determined to be 2.0 ± 1.0 mm (mean ± SD), and an overall system instrument targeting error of 3.0 ± 1.2 mm. Three needle deployments for each target phantom lesion was found to result in a 100% lesion hit rate and a median predicted cancer core length of 5.2 mm. The application of a comprehensive, unbiased validation assessment for MR/US guided systems can provide useful information on system performance for quality assurance and system comparison. Furthermore, such an analysis can be helpful in identifying relationships between these errors, providing insight into the technical behavior of these systems. © 2018 American Association of Physicists in Medicine.

Understanding the information and resource needs of UK health and social care placement students.

Science.gov (United States)

Callaghan, Lynne; Doherty, Alan; Lea, Susan J; Webster, Daniel

2008-12-01

Students on health and social care degree programmes spend 50% of their time on practice placements. Because of the diversity of settings and the need to evidence their work, it is vital to understand the information and resource needs of placement students. The aim of this investigation was to understand the needs of placement students in terms of accessing resources whilst they are in the field in order to inform a guide to meet these needs. Focus groups were conducted with students on midwifery, social work and post-registration health professions degree programmes on three different sites across the region. Data were analysed using Thematic Content Analysis. Three themes emerged from the data: inequality, user education needs and students' solutions and strategies. It is essential to speak to placement students in order to understand their needs in terms of accessing and using library resources. The timing and content of information skills training is key to meeting student needs while on placement.

Three-finger tracheal palpation to guide endotracheal tube depth in children.

Science.gov (United States)

Gamble, Jonathan J; McKay, William P; Wang, Andrew F; Yip, Kinsha A; O'Brien, Jennifer M; Plewes, Christopher E

2014-10-01

Accurate endotracheal tube (ETT) depth is critical, especially in children. The current tools used to guide appropriate ETT depth have significant limitations. To evaluate the utility of tracheal palpation in the neck to guide appropriate ETT placement in children. A prospective observational study with a convenience sample of 50 children was conducted. During intubation, an investigator palpated the trachea with three fingertips side-by-side extending upward from the suprasternal notch. The anesthesiologist advanced the ETT slowly until palpated at the sternal notch. The investigator stated ETT palpation certainty as 'strongly felt', 'weakly felt', or 'not felt.' Final ETT position was determined by bronchoscopy and categorized as 'ETT too shallow' (tip in proximal ¼ of trachea), 'ETT too deep' (tip in distal ¼ of trachea), or 'ETT placement satisfactory' (between those extremes). Thirty boys and 20 girls undergoing dental surgery with nasal intubation were recruited (median age 4.4 years; range 2.0-10.8). The ETT (all ≥4 mm ID) was palpable at the sternal notch in all patients: 46 of 50 strongly palpable and 4 of 50 weakly palpable. The experimental methods led to satisfactory ETT placement in 49 of 50 patients, too deep in 1 of 50 patients. Compared with the Pediatrics Advanced Life Support (PALS) predictive formula, satisfactory placement would have been 41 of 50 patients (P guide ETT placement has excellent clinical performance and better guides appropriate ETT depth than the PALS formula in our study population. © 2014 John Wiley & Sons Ltd.

Transesophageal Ultrasonography for Lung Cancer Staging

DEFF Research Database (Denmark)

Konge, Lars; Annema, Jouke; Vilmann, Peter

2013-01-01

Accurate mediastinal nodal staging is essential for patients with resectable non-small-cell lung cancer and is achieved by combined endobronchial ultrasound and transesophageal endoscopic ultrasound (EUS). Training requirements for EUS-guided fine-needle aspiration (FNA) for lung cancer staging...

Pretherapeutic evaluation of patients with upper gastrointestinal tract cancer using endoscopic and laparoscopic ultrasonography.

Science.gov (United States)

Mortensen, Michael Bau

2012-12-01

A detailed and correct pretherapeutic evaluation of stage and resectability is mandatory for an optimal treatment strategy and results in patients with cancer of the esophagus, stomach or pancreas (UGIC). Curative surgery should only be attempted in patients with limited extent of their disease, patients with locally advanced disease should be allocated for neo-adjuvant therapy, while the remaining patients should be referred for palliative measures following a quick, lenient and correct pretherapeutic evaluation. This thorough evaluation and subsequent treatment assignment is also valuable in the identification of uniform patient cohorts for new treatment protocols as well as for the continuing comparison of research data. But despite the importance of accurate pretherapeutic assessment being repeatedly emphasized insufficient staging has been - and is still accepted as - leading to high rates of explorative surgery as well as heterogeneous selection of patients for new treatment trials. Based on the results from the authors PhD thesis he concluded that endoscopic ultrasonography (EUS) as a single imaging modality provided detailed information that hitherto had been inaccessible. EUS was considered a significant progress regarding the loco-regional assessment of stage and resectability, but it was also evident that EUS alone was incapable of providing all the necessary information. In addition, there were no evidence regarding the EUS safety profile, patient tolerance of the procedure and no data on the clinical impact of both EUS and EUS guided fine-needle aspiration biopsy (EUS-FNA) in UGIC patients. Therefore, the author chose to conduct additional EUS trials and to test the use of EUS-FNA, laparoscopy (LAP), laparoscopic ultrasonography (LUS) and LUS guided biopsy in order to improve the overall pretherapeutic evaluation and thus the patient selection. The aim of this thesis was to describe the sequential development, testing and clinical results of a new

New endoscopic ultrasonography techniques for pancreticobiliary diseases

Energy Technology Data Exchange (ETDEWEB)

Kamata, Ken; Kitano, Masayuki; Omoto, Shunsuke; Kadosaka, Kumpei; Miyata, Takeshi; Minaga, Kosuke; Yamao, Kentaro; Imai, Hajime; Kudo, Masatoshii [Dept. of Gastroenterology and Hepatology, Kinki University Faculty of Medicine, Osaka (Japan)

2016-07-15

Endoscopic ultrasonography (EUS) is widely used to evaluate pancreaticobiliary diseases, especially pancreatic masses. EUS has a good ability to detect pancreatic masses, but it is not sufficient for the differential diagnosis of various types of lesions. In order to address the limitations of EUS, new techniques have been developed to improve the characterization of the lesions detected by EUS. EUS-guided fine needle aspiration (EUS-FNA) has been used for diagnosing pancreatic tumors. In order to improve the histological diagnostic yield, a EUS-FNA needle with a core trap has recently been developed. Contrast-enhanced harmonic EUS is a new imaging modality that uses an ultrasonographic contrast agent to visualize blood flow in fine vessels. This technique is useful in the diagnosis of pancreatic solid lesions and in confirming the presence of vascularity in mural nodules for cystic lesions. EUS elastography analyzes several different variables to measure tissue elasticity, color patterns, and strain ratio, using analytical techniques such as hue-histogram analysis, and artificial neural networks, which are useful for the diagnosis of chronic pancreatitis and pancreatic cancer.

TH-CD-207A-09: Stay On Target: Dynamic, Patient-Specific Templates of Fiducial Marker Clusters for IGRT

International Nuclear Information System (INIS)

Campbell, W; Miften, M; Jones, B

2016-01-01

Purpose: Pancreatic SBRT relies on extremely accurate delivery of ablative radiation doses to the target, and intra-fractional tracking of fiducial markers can facilitate improvements in dose delivery. However, this requires algorithms that are able to find fiducial markers with high speed and accuracy. The purpose of this study was to develop a novel marker tracking algorithm that is robust against many of the common errors seen with traditional template matching techniques. Methods: Using CBCT projection images, a method was developed to create detailed template images of fiducial marker clusters without prior knowledge of the number of markers, their positions, or their orientations. Briefly, the method (i) enhances markers in projection images, (ii) stabilizes the cluster’s position, (iii) reconstructs the cluster in 3D, and (iv) precomputes a set of static template images dependent on gantry angle. Furthermore, breathing data were used to produce 4D reconstructions of clusters, yielding dynamic template images dependent on gantry angle and breathing amplitude. To test these two approaches, static and dynamic templates were used to track the motion of marker clusters in more than 66,000 projection images from 75 CBCT scans of 15 pancreatic SBRT patients. Results: For both static and dynamic templates, the new technique was able to locate marker clusters present in projection images 100% of the time. The algorithm was also able to correctly locate markers in several instances where only some of the markers were visible due to insufficient field-of-view. In cases where clusters exhibited deformation and/or rotation during breathing, dynamic templates resulted in cross-correlation scores up to 70% higher than static templates. Conclusion: Patient-specific templates provided complete tracking of fiducial marker clusters in CBCT scans, and dynamic templates helped to provide higher cross-correlation scores for deforming/rotating clusters. This novel algorithm

TH-CD-207A-09: Stay On Target: Dynamic, Patient-Specific Templates of Fiducial Marker Clusters for IGRT

Energy Technology Data Exchange (ETDEWEB)

Campbell, W; Miften, M; Jones, B [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, CO (United States)

2016-06-15

Purpose: Pancreatic SBRT relies on extremely accurate delivery of ablative radiation doses to the target, and intra-fractional tracking of fiducial markers can facilitate improvements in dose delivery. However, this requires algorithms that are able to find fiducial markers with high speed and accuracy. The purpose of this study was to develop a novel marker tracking algorithm that is robust against many of the common errors seen with traditional template matching techniques. Methods: Using CBCT projection images, a method was developed to create detailed template images of fiducial marker clusters without prior knowledge of the number of markers, their positions, or their orientations. Briefly, the method (i) enhances markers in projection images, (ii) stabilizes the cluster’s position, (iii) reconstructs the cluster in 3D, and (iv) precomputes a set of static template images dependent on gantry angle. Furthermore, breathing data were used to produce 4D reconstructions of clusters, yielding dynamic template images dependent on gantry angle and breathing amplitude. To test these two approaches, static and dynamic templates were used to track the motion of marker clusters in more than 66,000 projection images from 75 CBCT scans of 15 pancreatic SBRT patients. Results: For both static and dynamic templates, the new technique was able to locate marker clusters present in projection images 100% of the time. The algorithm was also able to correctly locate markers in several instances where only some of the markers were visible due to insufficient field-of-view. In cases where clusters exhibited deformation and/or rotation during breathing, dynamic templates resulted in cross-correlation scores up to 70% higher than static templates. Conclusion: Patient-specific templates provided complete tracking of fiducial marker clusters in CBCT scans, and dynamic templates helped to provide higher cross-correlation scores for deforming/rotating clusters. This novel algorithm

Laboratory Guide for Residual Stress Sample Alignment and Experiment Planning-October 2011 Version

Energy Technology Data Exchange (ETDEWEB)

Cornwell, Paris A [ORNL; Bunn, Jeffrey R [ORNL; Schmidlin, Joshua E [ORNL; Hubbard, Camden R [ORNL

2012-04-01

The December 2010 version of the guide, ORNL/TM-2008/159, by Jeff Bunn, Josh Schmidlin, Camden Hubbard, and Paris Cornwell, has been further revised due to a major change in the GeoMagic Studio software for constructing a surface model. The Studio software update also includes a plug-in module to operate the FARO Scan Arm. Other revisions for clarity were also made. The purpose of this revision document is to guide the reader through the process of laser alignment used by NRSF2 at HFIR and VULCAN at SNS. This system was created to increase the spatial accuracy of the measurement points in a sample, reduce the use of neutron time used for alignment, improve experiment planning, and reduce operator error. The need for spatial resolution has been driven by the reduction in gauge volumes to the sub-millimeter level, steep strain gradients in some samples, and requests to mount multiple samples within a few days for relating data from each sample to a common sample coordinate system. The first step in this process involves mounting the sample on an indexer table in a laboratory set up for offline sample mounting and alignment in the same manner it would be mounted at either instrument. In the shared laboratory, a FARO ScanArm is used to measure the coordinates of points on the sample surface ('point cloud'), specific features and fiducial points. A Sample Coordinate System (SCS) needs to be established first. This is an advantage of the technique because the SCS can be defined in such a way to facilitate simple definition of measurement points within the sample. Next, samples are typically mounted to a frame of 80/20 and fiducial points are attached to the sample or frame then measured in the established sample coordinate system. The laser scan probe on the ScanArm can then be used to scan in an 'as-is' model of the sample as well as mounting hardware. GeoMagic Studio 12 is the software package used to construct the model from the point cloud the

Laboratory Guide for Residual Stress Sample Alignment and Experiment Planning-October 2011 Version

International Nuclear Information System (INIS)

Cornwell, Paris A.; Bunn, Jeffrey R.; Schmidlin, Joshua E.; Hubbard, Camden R.

2012-01-01

The December 2010 version of the guide, ORNL/TM-2008/159, by Jeff Bunn, Josh Schmidlin, Camden Hubbard, and Paris Cornwell, has been further revised due to a major change in the GeoMagic Studio software for constructing a surface model. The Studio software update also includes a plug-in module to operate the FARO Scan Arm. Other revisions for clarity were also made. The purpose of this revision document is to guide the reader through the process of laser alignment used by NRSF2 at HFIR and VULCAN at SNS. This system was created to increase the spatial accuracy of the measurement points in a sample, reduce the use of neutron time used for alignment, improve experiment planning, and reduce operator error. The need for spatial resolution has been driven by the reduction in gauge volumes to the sub-millimeter level, steep strain gradients in some samples, and requests to mount multiple samples within a few days for relating data from each sample to a common sample coordinate system. The first step in this process involves mounting the sample on an indexer table in a laboratory set up for offline sample mounting and alignment in the same manner it would be mounted at either instrument. In the shared laboratory, a FARO ScanArm is used to measure the coordinates of points on the sample surface ('point cloud'), specific features and fiducial points. A Sample Coordinate System (SCS) needs to be established first. This is an advantage of the technique because the SCS can be defined in such a way to facilitate simple definition of measurement points within the sample. Next, samples are typically mounted to a frame of 80/20 and fiducial points are attached to the sample or frame then measured in the established sample coordinate system. The laser scan probe on the ScanArm can then be used to scan in an 'as-is' model of the sample as well as mounting hardware. GeoMagic Studio 12 is the software package used to construct the model from the point cloud the scan arm creates. Once

Visibility and artifacts of gold fiducial markers used for image guided radiation therapy of pancreatic cancer on MRI

International Nuclear Information System (INIS)

Gurney-Champion, Oliver J.; Lens, Eelco; Horst, Astrid van der; Houweling, Antonetta C.; Tienhoven, Geertjan van; Bel, Arjan; Klaassen, Remy; Hooft, Jeanin E. van; Stoker, Jaap; Nederveen, Aart J.

2015-01-01

Purpose: In radiation therapy of pancreatic cancer, tumor alignment prior to each treatment fraction is improved when intratumoral gold fiducial markers (from here onwards: markers), which are visible on computed tomography (CT) and cone beam CT, are used. Visibility of these markers on magnetic resonance imaging (MRI) might improve image registration between CT and magnetic resonance (MR) images for tumor delineation purposes. However, concomitant image artifacts induced by markers are undesirable. The extent of visibility and artifact size depend on MRI-sequence parameters. The authors’ goal was to determine for various markers their potential to be visible and to generate artifacts, using measures that are independent of the MRI-sequence parameters. Methods: The authors selected ten different markers suitable for endoscopic placement in the pancreas and placed them into a phantom. The markers varied in diameter (0.28–0.6 mm), shape, and iron content (0%–0.5%). For each marker, the authors calculated T 2 ∗ -maps and ΔB 0 -maps using MRI measurements. A decrease in relaxation time T 2 ∗ can cause signal voids, associated with visibility, while a change in the magnetic field B 0 can cause signal shifts, which are associated with artifacts. These shifts inhibit accurate tumor delineation. As a measure for potential visibility, the authors used the volume of low T 2 ∗ , i.e., the volume for which T 2 ∗ differed from the background by >15 ms. As a measure for potential artifacts, the authors used the volume for which |ΔB 0 | > 9.4 × 10 −8 T (4 Hz). To test whether there is a correlation between visibility and artifact size, the authors calculated the Spearman’s correlation coefficient (R s ) between the volume of low T 2 ∗ and the volume of high |ΔB 0 |. The authors compared the maps with images obtained using a clinical MR-sequence. Finally, for the best visible marker as well as the marker that showed the smallest artifact, the authors

Patient-specific targeting guides compared with traditional instrumentation for glenoid component placement in shoulder arthroplasty: a multi-surgeon study in 70 arthritic cadaver specimens.

Science.gov (United States)

Throckmorton, Thomas W; Gulotta, Lawrence V; Bonnarens, Frank O; Wright, Stephen A; Hartzell, Jeffrey L; Rozzi, William B; Hurst, Jason M; Frostick, Simon P; Sperling, John W

2015-06-01

The purpose of this study was to compare the accuracy of patient-specific guides for total shoulder arthroplasty (TSA) with traditional instrumentation in arthritic cadaver shoulders. We hypothesized that the patient-specific guides would place components more accurately than standard instrumentation. Seventy cadaver shoulders with radiographically confirmed arthritis were randomized in equal groups to 5 surgeons of varying experience levels who were not involved in development of the patient-specific guidance system. Specimens were then randomized to patient-specific guides based off of computed tomography scanning, standard instrumentation, and anatomic TSA or reverse TSA. Variances in version or inclination of more than 10° and more than 4 mm in starting point were considered indications of significant component malposition. TSA glenoid components placed with patient-specific guides averaged 5° of deviation from the intended position in version and 3° in inclination; those with standard instrumentation averaged 8° of deviation in version and 7° in inclination. These differences were significant for version (P = .04) and inclination (P = .01). Multivariate analysis of variance to compare the overall accuracy for the entire cohort (TSA and reverse TSA) revealed patient-specific guides to be significantly more accurate (P = .01) for the combined vectors of version and inclination. Patient-specific guides also had fewer instances of significant component malposition than standard instrumentation did. Patient-specific targeting guides were more accurate than traditional instrumentation and had fewer instances of component malposition for glenoid component placement in this multi-surgeon cadaver study of arthritic shoulders. Long-term clinical studies are needed to determine if these improvements produce improved functional outcomes. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Liquid fiducial marker performance during radiotherapy of locally advanced non small cell lung cancer

DEFF Research Database (Denmark)

Rydhög, Jonas Scherman; Mortensen, Steen Riisgaard; Larsen, Klaus Richter

2016-01-01

We analysed the positional and structural stability of a long-term biodegradable liquid fiducial marker (BioXmark) for radiotherapy in patients with locally advanced lung cancer. Markers were injected via endoscopic- or endobronchial ultrasound in lymph nodes and reachable primary tumours. Marker...

Tailor-made Surgical Guide Reduces Incidence of Outliers of Cup Placement.

Science.gov (United States)

Hananouchi, Takehito; Saito, Masanobu; Koyama, Tsuyoshi; Sugano, Nobuhiko; Yoshikawa, Hideki

2010-04-01

Malalignment of the cup in total hip arthroplasty (THA) increases the risks of postoperative complications such as neck cup impingement, dislocation, and wear. We asked whether a tailor-made surgical guide based on CT images would reduce the incidence of outliers beyond 10 degrees from preoperatively planned alignment of the cup compared with those without the surgical guide. We prospectively followed 38 patients (38 hips, Group 1) having primary THA with the conventional technique and 31 patients (31 hips, Group 2) using the surgical guide. We designed the guide for Group 2 based on CT images and fixed it to the acetabular edge with a Kirschner wire to indicate the planned cup direction. Postoperative CT images showed the guide reduced the number of outliers compared with the conventional method (Group 1, 23.7%; Group 2, 0%). The surgical guide provided more reliable cup insertion compared with conventional techniques. Level II, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Keyword: Placement

Science.gov (United States)

Cassuto, Leonard

2012-01-01

The practical goal of graduate education is placement of graduates. But what does "placement" mean? Academics use the word without thinking much about it. "Placement" is a great keyword for the graduate-school enterprise. For one thing, its meaning certainly gives a purpose to graduate education. Furthermore, the word is a portal into the way of…

Role of endoscopic ultrasound in the diagnosis and staging of pancreatic cancer

DEFF Research Database (Denmark)

Saftoiu, Adrian; Vilmann, Peter

2009-01-01

. The introduction of EUS-guided fine needle aspiration allows a preoperative diagnosis in patients with resectable cancer, as well as a confirmation of diagnosis before chemoradiotherapy for those that are not. This comprehensive review highlighted the diagnostic capabilities of EUS including the newest refinements...

The Efficacy of the Coaxial Technique Using a 6-Fr Introducer Sheath in Stent Placement for Treating the Obstructions Proximal to the Descending Colon

Energy Technology Data Exchange (ETDEWEB)

Chang, Il Soo; Park, Sang Woo; Hwang, Dae Yong; Seong, Moo Kyung; Joh, Hee Kyung; Yoon, So Young; Cho, Yo Han; Choe, Won Hyeok [Konkuk University Hospital, Seoul (Korea, Republic of)

2011-02-15

We wanted to evaluate the efficacy of stent placement using the coaxial technique with a stiff, long introducer sheath in patients with technical failure using an angiographic catheter for the obstructions proximal to the descending colon. Self-expandable metallic stent placement was attempted under fluoroscopy-guidance in 77 consecutive patients who had malignant colorectal obstruction. Stent placement was performed using an angiographic catheter and a guide wire. If the angiographic catheter could not be advanced over the guide wire into the obstructive lesions proximal to the descending colon, then a 6-Fr introducer sheath was used. The technical success rate, the clinical success rate and the complications were analyzed. Successful stent placement was achieved in 75 of 77 patients (97%). The angiographic catheter failed to advance into the obstructive lesions of 11 patients (M:F = 7:4: mean age, 65.5 years) whose lesions were at the level of the splenic flexure or transverse colon. Therefore, the coaxial technique was implemented in all these 11 patients using a 6-Fr stiff introducer sheath and then the stent placement was successful. There were no complications related to the use of a stiff introducer sheath. Clinical success, which was defined as relief of clinical obstructive bowel symptoms, was obtained within 24 hours in all of patients. The coaxial technique using a stiff introducer sheath can increase the technical success of fluoroscopy-guided, self-expandable metallic stent placement in patients with colonic obstruction proximal to the descending colon

The Efficacy of the Coaxial Technique Using a 6-Fr Introducer Sheath in Stent Placement for Treating the Obstructions Proximal to the Descending Colon

International Nuclear Information System (INIS)

Chang, Il Soo; Park, Sang Woo; Hwang, Dae Yong; Seong, Moo Kyung; Joh, Hee Kyung; Yoon, So Young; Cho, Yo Han; Choe, Won Hyeok

2011-01-01

We wanted to evaluate the efficacy of stent placement using the coaxial technique with a stiff, long introducer sheath in patients with technical failure using an angiographic catheter for the obstructions proximal to the descending colon. Self-expandable metallic stent placement was attempted under fluoroscopy-guidance in 77 consecutive patients who had malignant colorectal obstruction. Stent placement was performed using an angiographic catheter and a guide wire. If the angiographic catheter could not be advanced over the guide wire into the obstructive lesions proximal to the descending colon, then a 6-Fr introducer sheath was used. The technical success rate, the clinical success rate and the complications were analyzed. Successful stent placement was achieved in 75 of 77 patients (97%). The angiographic catheter failed to advance into the obstructive lesions of 11 patients (M:F = 7:4: mean age, 65.5 years) whose lesions were at the level of the splenic flexure or transverse colon. Therefore, the coaxial technique was implemented in all these 11 patients using a 6-Fr stiff introducer sheath and then the stent placement was successful. There were no complications related to the use of a stiff introducer sheath. Clinical success, which was defined as relief of clinical obstructive bowel symptoms, was obtained within 24 hours in all of patients. The coaxial technique using a stiff introducer sheath can increase the technical success of fluoroscopy-guided, self-expandable metallic stent placement in patients with colonic obstruction proximal to the descending colon

[Overal cognitive assessment in Basque-speaking people with advanced dementia. Validation to the Basque language of the Severe Mini-Mental State Examination SMMSE (SMMSE-eus)].

Science.gov (United States)

Buiza, Cristina; Yanguas, Javier; Zulaica, Amaia; Antón, Iván; Arriola, Enrique; García, Alvaro

2018-04-13

Adaptation and validation to the Basque language of tests to assess advanced cognitive impairment is a not covered need for Basque-speaking people. The present work shows the validation of the Basque version of the Severe Mini Mental State Examination (SMMSE). A total of 109 people with advanced dementia (MECinternal consistency (alpha=0.92), a good test-retest reliability (r=0.88; Pinternal consistency and inter-rater reliability, and to a lesser extent, test-retest reliability, made the SMMSE-eus a valid test for the brief assessment of cognitive status in people with advanced dementia in Basque-speaking people. For this reason, the SMMSE-eus is a usable and reliable alternative for assessing Basque-speaking people in their mother-tongue, or preferred language. Copyright © 2017 SEGG. Publicado por Elsevier España, S.L.U. All rights reserved.

Lack of Correlation Between External Fiducial Positions and Internal Tumor Positions During Breath-Hold CT

International Nuclear Information System (INIS)

Hunjan, Sandeep; Starkschall, George; Prado, Karl; Dong Lei; Balter, Peter

2010-01-01

Purpose: For thoracic tumors, if four-dimensional computed tomography (4DCT) is unavailable, the internal margin can be estimated by use of breath-hold (BH) CT scans acquired at end inspiration (EI) and end expiration (EE). By use of external surrogates for tumor position, BH accuracy is estimated by minimizing the difference between respiratory extrema BH and mean equivalent-phase free breathing (FB) positions. We tested the assumption that an external surrogate for BH accuracy correlates with internal tumor positional accuracy during BH CT. Methods and Materials: In 16 lung cancer patients, 4DCT images, as well as BH CT images at EI and EE, were acquired. Absolute differences between BH and mean equivalent-phase (FB) positions were calculated for both external fiducials and gross tumor volume (GTV) centroids as metrics of external and internal BH accuracy, respectively, and the results were correlated. Results: At EI, the absolute difference between mean FB and BH fiducial displacement correlated poorly with the absolute difference between FB and BH GTV centroid positions on CT images (R 2 = 0.11). Similarly, at EE, the absolute difference between mean FB and BH fiducial displacements correlated poorly with the absolute difference between FB and BH GTV centroid positions on CT images (R 2 = 0.18). Conclusions: External surrogates for tumor position are not an accurate metric of BH accuracy for lung cancer patients. This implies that care should be taken when using such an approach because an incorrect internal margin could be generated.

Measurement of Neutrino Oscillation Parameters Using Anti-fiducial Charged Current Events in MINOS

Energy Technology Data Exchange (ETDEWEB)

Strait, Matthew Levy [Univ. of Minnesota, Minneapolis, MN (United States)

2010-09-01

Abstract The Main Injector Neutrino Oscillation Search (MINOS) obse rves the disappearance of muon neutrinos as they propagate in the long baseline Neutri nos at the Main Injector (NuMI) beam. MINOS consists of two detectors. The near detector sam ples the initial composition of the beam. The far detector, 735 km away, looks for an energy-d ependent deficit in the neutrino spectrum. This energy-dependent deficit is interpreted as q uantum mechanical oscillations be- tween neutrino flavors. A measurement is made of the effective two-neutrino mixing parameters Δ m 2 ≈ Δ m ² 23 and sin ² 2 θ ≈ sin ² 2 θ ₂₃ . The primary MINOS analysis uses charged current events in the fiducial volume of the far detector. This analysis uses the roughly equal-sized sample of events that fails the fiducial cut, consisting of interact ions outside the fiducial region of the detector and in the surrounding rock. These events provide a n independent and complementary measurement, albeit weaker due to incomplete reconstructi on of the events. This analysis reports on an exposure of 7 . 25 × 10 ²⁰ protons-on-target. Due to poor energy resolution, the meas urement of sin ² 2 θ is much weaker than established results, but the measuremen t of sin ² 2 θ > 0 . 56 at 90% confidence is consistent with the accepted value. The measur ement of Δ m 2 is much stronger. Assuming sin 2 ² θ = 1 , Δ m ² = (2 . 20 ± 0 . 18[stat] ± 0 . 14[syst]) × 10 - ^-3 eV ² .

Endosonography-related mortality and morbidity for pulmonary indications: a nationwide survey in the Netherlands.

Science.gov (United States)

von Bartheld, Martin B; Annema, Jouke T

2015-12-01

Endosonography is being implemented rapidly in pulmonary medicine for the diagnosis and staging of lung cancer, the assessment of sarcoidosis, and the assessment of mediastinal lesions. Although serious adverse events (SAEs) have been described, safety data outside cohort studies are scarce. To assess the SAE and mortality rate of EUS-guided FNA (EUS-FNA) and endobronchial ultrasound guided transbronchial needle aspiration (EBUS-TBNA) for mediastinal and/or hilar analysis. Nationwide, retrospective survey by using questionnaires. All hospitals in the Netherlands. All patients undergoing EUS-FNA and EBUS-TBNA for intrathoracic analysis in the period 1999 to 2011. EUS-FNA and EBUS-TBNA. Occurrence of fatal outcomes and SAEs. Detailed information was obtained for each reported case, and all cases were reviewed independently by 2 investigators, including identification of risk factors. All 89 hospitals (100%) responded. An estimated 14,075 EUS-FNA and 2675 EBUS procedures were performed. Seven patients died after endosonography (5 EUS-FNA, 2 EBUS [mortality rate 0.04%]). All fatalities occurred in patients of poor performance status (American Society of Anesthesiologists Physical Status Classification System score of III/IV). Twenty-five SAEs were reported (22 EUS-FNA, 3 EBUS [SAE rate of 0.15%; EUS-FNA 0.16%, EBUS 0.11%]). SAEs were mostly (64%) of infectious origin. No specific risk factors for infectious adverse events could be identified. Retrospective study, possible recall bias, overrepresentation of EUS-FNA cases. Endosonography appears to be a safe technique for the analysis of mediastinal and/or hilar lesions. Poor performance status is a risk factor for fatal outcomes. Mediastinitis and/or mediastinal abscess formation is rare but is a potential and dangerous adverse event of endosonography. Copyright © 2015 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

Respiratory-Gated Proton Beam Therapy for Hepatocellular Carcinoma Adjacent to the Gastrointestinal Tract without Fiducial Markers

Directory of Open Access Journals (Sweden)

Miu Mizuhata

2018-02-01

Full Text Available The efficacy of proton beam therapy (PBT for hepatocellular carcinoma (HCC has been reported, but insertion of fiducial markers in the liver is usually required. We evaluated the efficacy and toxicity of respiratory-gated PBT without fiducial markers for HCC located within 2 cm of the gastrointestinal tract. From March 2011 to December 2015 at our institution, 40 patients were evaluated (median age, 72 years; range, 38–87 years. All patients underwent PBT at a dose of 60 to 80 cobalt gray equivalents (CGE in 20 to 38 fractions. The median follow-up period was 19.9 months (range, 1.2–72.3 months. The median tumor size was 36.5 mm (range, 11–124 mm. Kaplan–Meier estimates of the 2-year overall survival, progression-free survival, and local tumor control rates were 76%, 60%, and 94%, respectively. One patient (2.5% developed a grade 3 gastric ulcer and one (2.5% developed grade 3 ascites retention; none of the remaining patients developed grade >3 toxicities (National Cancer Institute Common Terminology Criteria for Adverse Events ver. 4.0.. This study indicates that PBT without fiducial markers achieves good local control without severe treatment-related toxicity of the gastrointestinal tract for HCC located within 2 cm of the gastrointestinal tract.

Measurement of the Higgs boson fiducial and differential cross sections in the 4\\ell decay channel at 13 TeV with the ATLAS detector

CERN Document Server

Salvucci, Antonio; The ATLAS collaboration

2017-01-01

This poster presents a measurement of the inclusive and differential fiducial cross sections of Higgs-boson production in the four leptons (electrons or muons) final state. The data sample, collected by the ATLAS experiment in 2015 and 2016, corresponds to an integrated luminosity of \\SI{36.1}{\\per\\femto\\barn} of proton-proton collisions produced at the Large Hadron Collider at a centre-of-mass energy of \\SI{13}{\\TeV}. The inclusive fiducial cross section has been measured to be in agreement with the Standard Model (SM) prediction. Moreover, several differential fiducial cross sections have been measured for observables sensitive to the Higgs-boson production and decay. Good agreement has been found between data and SM predictions.

Endoscopic ultrasound in the diagnosis and staging of pancreatic cancer

Directory of Open Access Journals (Sweden)

J. Iglesias García

Full Text Available Pancreatic cancer is the 5th leading cause of cancer-related death in Western countries. The 5-year survival rate is approximately 4%, without significant changes over the last 50 years. This poor survival rate and bad prognosis are associated with the diagnosis of advanced-stage disease, which precludes the only potential curative treatment - surgical resection. In this setting, the main objective in the management of pancreatic cancer is to perform an early diagnosis and a correct staging of the disease. Endoscopic ultrasonography (EUS appears to be an essential tool for the diagnosis and staging of pancreatic cancer. EUS diagnostic accuracy for detecting pancreatic tumors ranges from 85 to 100%, clearly superior to other imaging techniques. EUS accuracy for the local staging of pancreatic cancer ranges from 70 to 90%, superior or equivalent to other imaging modalities. EUS-guided fine-needle aspiration allows a cyto-histological diagnosis in nearly 90% of cases, with a very low complication rate. At present, the formal indications for EUS-guided fine-needle aspiration are the necessity of palliative treatment or whenever the possibility of neoadjuvant treatment is present. It could be also indicated to differentiate pancreatic adenocarcinoma from other pancreatic conditions, like lymphoma, metastasis, autoimmune pancreatitis or chronic pancreatitis. We can conclude that EUS is an essential tool in the management of patients with pancreatic tumors.

Endoscopic ultrasound in the diagnosis and staging of pancreatic cancer

Directory of Open Access Journals (Sweden)

J. Iglesias García

2009-09-01

Full Text Available Pancreatic cancer is the 5th leading cause of cancer-related death in Western countries. The 5-year survival rate is approximately 4%, without significant changes over the last 50 years. This poor survival rate and bad prognosis are associated with the diagnosis of advanced-stage disease, which precludes the only potential curative treatment - surgical resection. In this setting, the main objective in the management of pancreatic cancer is to perform an early diagnosis and a correct staging of the disease. Endoscopic ultrasonography (EUS appears to be an essential tool for the diagnosis and staging of pancreatic cancer. EUS diagnostic accuracy for detecting pancreatic tumors ranges from 85 to 100%, clearly superior to other imaging techniques. EUS accuracy for the local staging of pancreatic cancer ranges from 70 to 90%, superior or equivalent to other imaging modalities. EUS-guided fine-needle aspiration allows a cyto-histological diagnosis in nearly 90% of cases, with a very low complication rate. At present, the formal indications for EUS-guided fine-needle aspiration are the necessity of palliative treatment or whenever the possibility of neoadjuvant treatment is present. It could be also indicated to differentiate pancreatic adenocarcinoma from other pancreatic conditions, like lymphoma, metastasis, autoimmune pancreatitis or chronic pancreatitis. We can conclude that EUS is an essential tool in the management of patients with pancreatic tumors.

3D Printing Guide Implant Placement: A Case Report

Directory of Open Access Journals (Sweden)

Vlahović Zoran

2017-03-01

Full Text Available Background: Cone Beam Computer Tomography (CBCT is representing a new concept of radiological diagnostics and its application occupies a special place in implantology. Today, preoperative planning, and quantitative and qualitative jaw bone analysis cannot be done without the use of these techniques. The latest in a series of achievements in this field is a method of making a guide for implant using a 3D printing technique. This way pre implantology planning reduces the chance of surgical complications to a minimum and allows installation of dental implants in the most optimal position for future prosthetic work. Aim: To show benefits of guide implantation in clinical practice.

Les "Questions et réponses sur les évangiles" d'Eusèbe de Césarée: étude et édition du résumé grec

OpenAIRE

Zamagni, Claudio; Junod, Eric; Le Boulluec, Alain

2005-01-01

Cette thèse propose la première édition critique de l’une des traditions les plus importantes des Questions et réponses sur les évangiles d’Eusèbe de Césarée, dont l’original est perdu. Il s’agit de l’édition du manuscrit contenant l’anthologie grecque du manuscrit Vaticanus Pal. Gr. 220. Cette anthologie est composée presque intégralement d’une suite d’extraits du texte original, non résumés, dont l’auteur n’est pas Eusèbe et dont la date ne peut pas être reportée avant le V-VIème siècle. Ce...

MRI-guided prostate focal laser ablation therapy using a mechatronic needle guidance system

Science.gov (United States)

Cepek, Jeremy; Lindner, Uri; Ghai, Sangeet; Davidson, Sean R. H.; Trachtenberg, John; Fenster, Aaron

2014-03-01

Focal therapy of localized prostate cancer is receiving increased attention due to its potential for providing effective cancer control in select patients with minimal treatment-related side effects. Magnetic resonance imaging (MRI)-guided focal laser ablation (FLA) therapy is an attractive modality for such an approach. In FLA therapy, accurate placement of laser fibers is critical to ensuring that the full target volume is ablated. In practice, error in needle placement is invariably present due to pre- to intra-procedure image registration error, needle deflection, prostate motion, and variability in interventionalist skill. In addition, some of these sources of error are difficult to control, since the available workspace and patient positions are restricted within a clinical MRI bore. In an attempt to take full advantage of the utility of intraprocedure MRI, while minimizing error in needle placement, we developed an MRI-compatible mechatronic system for guiding needles to the prostate for FLA therapy. The system has been used to place interstitial catheters for MRI-guided FLA therapy in eight subjects in an ongoing Phase I/II clinical trial. Data from these cases has provided quantification of the level of uncertainty in needle placement error. To relate needle placement error to clinical outcome, we developed a model for predicting the probability of achieving complete focal target ablation for a family of parameterized treatment plans. Results from this work have enabled the specification of evidence-based selection criteria for the maximum target size that can be confidently ablated using this technique, and quantify the benefit that may be gained with improvements in needle placement accuracy.

Usefulness of normal saline for sealing the needle track after CT-guided lung biopsy

International Nuclear Information System (INIS)

Li, Y.; Du, Y.; Luo, T.Y.; Yang, H.F.; Yu, J.H.; Xu, X.X.; Zheng, H.J.; Li, B.

2015-01-01

Aim: To determine whether the use of normal saline for sealing the needle track can reduce the incidence of pneumothorax and chest tube placement after computed tomography (CT)-guided lung biopsy. Materials and methods: A prospective, randomised, controlled trial enrolling 322 patients was conducted. All patients were randomly assigned to one of two groups: those in whom the needle track was not sealed with normal saline (n=161, Group A) and those who did receive normal saline (n=161, Group B). CT-guided biopsy was performed with coaxial technique. Normal saline, which ranged from 1–3 ml, was injected while the trocar needle was being withdrawn. Patient characteristics, lesion, and procedure variables were analysed as potential risk variables for occurrence of pneumothorax and chest tube placement. Results: The incidence of pneumothorax was 26.1% in Group A and 6.2% in Group B (p<0.001). Nine patients in Group A and one patient in Group B required chest tube placement (p=0.010). Using multiple logistic regression analysis, smaller lesion size, greater needle–pleural angle, longer lesion–pleural distance, presence of emphysema, and no sealing the needle track with normal saline were significantly associated with an increased risk of pneumothorax, and that the latter three factors were also associated with an increased risk of pneumothorax requiring chest tube placement. Conlusion: Normal saline for sealing the needle track significantly reduces the incidence of pneumothorax and prevents subsequent chest tube placement after CT-guided lung biopsy. - Highlights: • Normal saline is an effective sealant for use in lung biopsy. • This technique reduced the incidence of pneumothorax and chest tube placement. • This technique should be recommended for CT-guided lung biopsy.

Pneumatically Operated MRI-Compatible Needle Placement Robot for Prostate Interventions

OpenAIRE

Fischer, Gregory S.; Iordachita, Iulian; Csoma, Csaba; Tokuda, Junichi; Mewes, Philip W.; Tempany, Clare M.; Hata, Nobuhiko; Fichtinger, Gabor

2008-01-01

Magnetic Resonance Imaging (MRI) has potential to be a superior medical imaging modality for guiding and monitoring prostatic interventions. The strong magnetic field prevents the use of conventional mechatronics and the confined physical space makes it extremely challenging to access the patient. We have designed a robotic assistant system that overcomes these difficulties and promises safe and reliable intra-prostatic needle placement inside closed high-field MRI scanners. The robot perform...

CT fluoroscopy-guided vs. multislice CT biopsy mode-guided lung biopsies: Accuracy, complications and radiation dose

International Nuclear Information System (INIS)

Prosch, Helmut; Stadler, Alfred; Schilling, Matthias; Bürklin, Sandra; Eisenhuber, Edith; Schober, Ewald; Mostbeck, Gerhard

2012-01-01

Background: The aim of this retrospective study was to compare the diagnostic accuracy, the frequency of complications, the duration of the interventions and the radiation doses of CT fluoroscopy (CTF) guided biopsies of lung lesions with those of multislice CT (MS-CT) biopsy mode-guided biopsies. Methods: Data and images from 124 consecutive patients undergoing CTF-guided lung biopsy (group A) and 132 MS-CT-biopsy mode-guided lung biopsy (group B) were reviewed. CTF-guided biopsies were performed on a Siemens Emotion 6 CT scanner with intermittent or continuous CT-fluoroscopy, MS-CT biopsy mode-guided biopsies were performed on a Siemens Emotion 16 CT scanner. All biopsies were performed with a coaxial needle technique. Results: The two groups (A vs. B) did not differ significantly regarding sensitivity (95.5% vs. 95.9%), specificity (96.7% vs. 95.5%), negative predictive value (87.9% vs. 84%) or positive predictive value (98.8% vs. 98.9%). Pneumothorax was observed in 30.0% and 32.5% of the patients, respectively. Chest tube placement was necessary in 4% (group A) and 13% (group B) of the patients. The duration of the intervention was significantly longer in group A (median 37 min vs. 32 min, p = 0.04). The mean CT dose index (CTDI) was 422 in group A and 36.3 in group B (p < 0.001). Conclusion: Compared to CTF-guided biopsies, chest biopsies using the MS-CT biopsy mode show dramatically lower CTDI levels. Although the diagnostic yield of the procedures do not differ significantly, biopsies using the MS-CT-biopsy mode have a three-fold higher rate of chest tube placement.

Timing-Constrained FPGA Placement: A Force-Directed Formulation and Its Performance Evaluation

Directory of Open Access Journals (Sweden)

Srilata Raman

1996-01-01

Full Text Available In this paper we present a simple but efficient timing-driven placement algorithm for FPGAs. The algorithm computes forces acting on a logic block in the FPGA to determine its relative location with respect to other blocks. The forces depend on the criticality of nets shared between the two blocks. Unlike other net-based approaches, timing constraints are incorporated directly into the force equations to guide the placement. Slot assignment is then used to move the blocks into valid slot locations on the FPGA chip. The assignment algorithm also makes use of the delay information of nets so that the final placement is able to meet the timing criteria specified for the circuit. The novelty of the approach lies in the formulation of the force equations and the manner in which weights of the nets are dynamically altered to influence the placement. Experiments conducted on industrial test circuits and MCNC circuits give very promising results and indicate that the algorithm succeeds in significantly reducing the maximum delay in the circuit. In addition, routability is not adversely affected and running time is low.

Development of the Animal Management and Husbandry Online Placement Tool.

Science.gov (United States)

Bates, Lucy; Crowther, Emma; Bell, Catriona; Kinnison, Tierney; Baillie, Sarah

2013-01-01

The workplace provides veterinary students with opportunities to develop a range of skills, making workplace learning an important part of veterinary education in many countries. Good preparation for work placements is vital to maximize learning; to this end, our group has developed a series of three computer-aided learning (CAL) packages to support students. The third of this series is the Animal Management and Husbandry Online Placement Tool (AMH OPT). Students need a sound knowledge of animal husbandry and the ability to handle the common domestic species. However, teaching these skills at university is not always practical and requires considerable resources. In the UK, the Royal College of Veterinary Surgeons (RCVS) requires students to complete 12 weeks of pre-clinical animal management and husbandry work placements or extramural studies (EMS). The aims are for students to improve their animal handling skills and awareness of husbandry systems, develop communication skills, and understand their future clients' needs. The AMH OPT is divided into several sections: Preparation, What to Expect, Working with People, Professionalism, Tips, and Frequently Asked Questions. Three stakeholder groups (university EMS coordinators, placement providers, and students) were consulted initially to guide the content and design and later to evaluate previews. Feedback from stakeholders was used in an iterative design process, resulting in a program that aims to facilitate student preparation, optimize the learning opportunities, and improve the experience for both students and placement providers. The CAL is available online and is open-access worldwide to support students during veterinary school.

Image-guided radiotherapy in near real time with intensity-modulated radiotherapy megavoltage treatment beam imaging.

Science.gov (United States)

Mao, Weihua; Hsu, Annie; Riaz, Nadeem; Lee, Louis; Wiersma, Rodney; Luxton, Gary; King, Christopher; Xing, Lei; Solberg, Timothy

2009-10-01

To utilize image-guided radiotherapy (IGRT) in near real time by obtaining and evaluating the online positions of implanted fiducials from continuous electronic portal imaging device (EPID) imaging of prostate intensity-modulated radiotherapy (IMRT) delivery. Upon initial setup using two orthogonal images, the three-dimensional (3D) positions of all implanted fiducial markers are obtained, and their expected two-dimensional (2D) locations in the beam's-eye-view (BEV) projection are calculated for each treatment field. During IMRT beam delivery, EPID images of the megavoltage treatment beam are acquired in cine mode and subsequently analyzed to locate 2D locations of fiducials in the BEV. Simultaneously, 3D positions are estimated according to the current EPID image, information from the setup portal images, and images acquired at other gantry angles (the completed treatment fields). The measured 2D and 3D positions of each fiducial are compared with their expected 2D and 3D setup positions, respectively. Any displacements larger than a predefined tolerance may cause the treatment system to suspend the beam delivery and direct the therapists to reposition the patient. Phantom studies indicate that the accuracy of 2D BEV and 3D tracking are better than 1 mm and 1.4 mm, respectively. A total of 7330 images from prostate treatments were acquired and analyzed, showing a maximum 2D displacement of 6.7 mm and a maximum 3D displacement of 6.9 mm over 34 fractions. This EPID-based, real-time IGRT method can be implemented on any external beam machine with portal imaging capabilities without purchasing any additional equipment, and there is no extra dose delivered to the patient.

Conventional multi-slice computed tomography (CT) and cone-beam CT (CBCT) for computer-aided implant placement. Part II: reliability of mucosa-supported stereolithographic guides.

Science.gov (United States)

Arisan, Volkan; Karabuda, Zihni Cüneyt; Pişkin, Bülent; Özdemir, Tayfun

2013-12-01

Deviations of implants that were placed by conventional computed tomography (CT)- or cone beam CT (CBCT)-derived mucosa-supported stereolithographic (SLA) surgical guides were analyzed in this study. Eleven patients were randomly scanned by a multi-slice CT (CT group) or a CBCT scanner (CBCT group). A total of 108 implants were planned on the software and placed using SLA guides. A new CT or CBCT scan was obtained and merged with the planning data to identify the deviations between the planned and placed implants. Results were analyzed by Mann-Whitney U test and multiple regressions (p < .05). Mean angular and linear deviations in the CT group were 3.30° (SD 0.36), and 0.75 (SD 0.32) and 0.80 mm (SD 0.35) at the implant shoulder and tip, respectively. In the CBCT group, mean angular and linear deviations were 3.47° (SD 0.37), and 0.81 (SD 0.32) and 0.87 mm (SD 0.32) at the implant shoulder and tip, respectively. No statistically significant differences were detected between the CT and CBCT groups (p = .169 and p = .551, p = .113 for angular and linear deviations, respectively). Implant placement via CT- or CBCT-derived mucosa-supported SLA guides yielded similar deviation values. Results should be confirmed on alternative CBCT scanners. © 2012 Wiley Periodicals, Inc.

Fast-MICP for frameless image-guided surgery

International Nuclear Information System (INIS)

Lee, Jiann-Der; Huang, Chung-Hsien; Wang, Sheng-Ta; Lin, Chung-Wei; Lee, Shin-Tseng

2010-01-01

Purpose: In image-guided surgery (IGS) systems, image-to-physical registration is critical for reliable anatomical information mapping and spatial guidance. Conventional stereotactic frame-based or fiducial-based approaches provide accurate registration but are not patient-friendly. This study proposes a frameless cranial IGS system that uses computer vision techniques to replace the frame or fiducials with the natural features of the patient. Methods: To perform a cranial surgery with the proposed system, the facial surface of the patient is first reconstructed by stereo vision. Accuracy is ensured by capturing parallel-line patterns projected from a calibrated LCD projector. Meanwhile, another facial surface is reconstructed from preoperative computed tomography (CT) images of the patient. The proposed iterative closest point (ICP)-based algorithm [fast marker-added ICP (Fast-MICP)] is then used to register the two facial data sets, which transfers the anatomical information from the CT images to the physical space. Results: Experimental results reveal that the Fast-MICP algorithm reduces the computational cost of marker-added ICP (J.-D. Lee et al., ''A coarse-to-fine surface registration algorithm for frameless brain surgery,'' in Proceedings of International Conference of the IEEE Engineering in Medicine and Biology Society, 2007, pp. 836-839) to 10% and achieves comparable registration accuracy, which is under 3 mm target registration error (TRE). Moreover, two types of optical-based spatial digitizing devices can be integrated for further surgical navigation. Anatomical information or image-guided surgical landmarks can be projected onto the patient to obtain an immersive augmented reality environment. Conclusion: The proposed frameless IGS system with stereo vision obtains TRE of less than 3 mm. The proposed Fast-MICP registration algorithm reduces registration time by 90% without compromising accuracy.

Fast-MICP for frameless image-guided surgery

Energy Technology Data Exchange (ETDEWEB)

Lee, Jiann-Der; Huang, Chung-Hsien; Wang, Sheng-Ta; Lin, Chung-Wei; Lee, Shin-Tseng [Department of Electrical Engineering, Chang Gung University, Tao-Yuan 333, Taiwan (China); Department of Medical Mechatronics, Chang Gung University, Tao-Yuan 333, Taiwan (China); Department of Neurosurgery and Medical Augmented Reality Research Center, Chang Gung Memorial Hospital, No. 199, Tunghwa Rd., Taipei 105, Taiwan (China)

2010-09-15

Purpose: In image-guided surgery (IGS) systems, image-to-physical registration is critical for reliable anatomical information mapping and spatial guidance. Conventional stereotactic frame-based or fiducial-based approaches provide accurate registration but are not patient-friendly. This study proposes a frameless cranial IGS system that uses computer vision techniques to replace the frame or fiducials with the natural features of the patient. Methods: To perform a cranial surgery with the proposed system, the facial surface of the patient is first reconstructed by stereo vision. Accuracy is ensured by capturing parallel-line patterns projected from a calibrated LCD projector. Meanwhile, another facial surface is reconstructed from preoperative computed tomography (CT) images of the patient. The proposed iterative closest point (ICP)-based algorithm [fast marker-added ICP (Fast-MICP)] is then used to register the two facial data sets, which transfers the anatomical information from the CT images to the physical space. Results: Experimental results reveal that the Fast-MICP algorithm reduces the computational cost of marker-added ICP (J.-D. Lee et al., ''A coarse-to-fine surface registration algorithm for frameless brain surgery,'' in Proceedings of International Conference of the IEEE Engineering in Medicine and Biology Society, 2007, pp. 836-839) to 10% and achieves comparable registration accuracy, which is under 3 mm target registration error (TRE). Moreover, two types of optical-based spatial digitizing devices can be integrated for further surgical navigation. Anatomical information or image-guided surgical landmarks can be projected onto the patient to obtain an immersive augmented reality environment. Conclusion: The proposed frameless IGS system with stereo vision obtains TRE of less than 3 mm. The proposed Fast-MICP registration algorithm reduces registration time by 90% without compromising accuracy.

Reliability of implant surgical guides based on soft-tissue models.

Science.gov (United States)

Maney, Pooja; Simmons, David E; Palaiologou, Archontia; Kee, Edwin

2012-12-01

The purpose of this study was to determine the accuracy of implant surgical guides fabricated on diagnostic casts. Guides were fabricated with radiopaque rods representing implant positions. Cone beam computerized tomograms were taken with guides in place. Accuracy was evaluated using software to simulate implant placement. Twenty-two sites (47%) were considered accurate (13 of 24 maxillary and 9 of 23 mandibular sites). Soft-tissue models do not always provide sufficient accuracy for fabricating implant surgical guides.

Incidence of bacteremia in cirrhotic patients undergoing upper endoscopic ultrasonography.

Science.gov (United States)

Fernández-Esparrach, Gloria; Sendino, Oriol; Araujo, Isis; Pellisé, Maria; Almela, Manel; González-Suárez, Begoña; López-Cerón, María; Córdova, Henry; Sanabria, Erwin; Uchima, Hugo; Llach, Josep; Ginès, Àngels

2014-01-01

The incidence of bacteremia after endoscopic ultrasonography (EUS) or EUS-guided fine-needle aspiration (EUS-FNA) is between 0% and 4%, but there are no data on this topic in cirrhotic patients. To prospectively assess the incidence of bacteremia in cirrhotic patients undergoing EUS and EUS-FNA. We enrolled 41 cirrhotic patients. Of these, 16 (39%) also underwent EUS-FNA. Blood cultures were obtained before and at 5 and 30 min after the procedure. When EUS-FNA was used, an extra blood culture was obtained after the conclusion of radial EUS and before the introduction of the sectorial echoendoscope. All patients were clinically followed up for 7 days for signs of infection. Blood cultures were positive in 16 patients. In 10 patients, blood cultures grew coagulase-negative Staphylococcus, Corynebacterium species, Propionibacterium species or Acinetobacterium Lwoffii, which were considered contaminants (contamination rate 9.8%, 95% CI: 5.7-16%). The remaining 6 patients had true positive blood cultures and were considered to have had true bacteremia (15%, 95% CI: 4-26%). Blood cultures were positive after diagnostic EUS in five patients but were positive after EUS-FNA in only one patient. Thus, the frequency of bacteremia after EUS and EUS-FNA was 12% and 6%, respectively (95% CI: 2-22% and 0.2-30%, respectively). Only one of the patients who developed bacteremia after EUS had a self-limiting fever with no other signs of infection. Asymptomatic Gram-positive bacteremia developed in cirrhotic patients after EUS and EUS-FNA at a rate higher than in non-cirrhotic patients. However, this finding was not associated with any clinically significant infections. Copyright © 2013 Elsevier España, S.L. and AEEH y AEG. All rights reserved.

Role of endoscopic ultrasonography in treatment and prognostic evaluation of esophageal and gastric varices

Directory of Open Access Journals (Sweden)

LI Shuang

2016-12-01

Full Text Available Through a comprehensive evaluation of collateral circulation establishment in portal hypertension, endoscopic ultrasonography (EUS not only helps to predict and evaluate the risks of first bleeding from esophageal and gastric varices and recurrence and rebleeding after treatment, but also guides and participates in the treatment of varices. This article introduces the unique advantages of EUS in the treatment and prognostic evaluation of esophageal and gastric varices and provides an important reference for individualized treatment of patients with liver cirrhosis complicated by esophageal and gastric varices. EUS also helps to improve treatment safety and response rate. EUS for the systematic treatment of portal hypertension has become a hot research topic in recent years.

Active illumination based 3D surface reconstruction and registration for image guided medialization laryngoplasty

Science.gov (United States)

Jin, Ge; Lee, Sang-Joon; Hahn, James K.; Bielamowicz, Steven; Mittal, Rajat; Walsh, Raymond

2007-03-01

The medialization laryngoplasty is a surgical procedure to improve the voice function of the patient with vocal fold paresis and paralysis. An image guided system for the medialization laryngoplasty will help the surgeons to accurately place the implant and thus reduce the failure rates of the surgery. One of the fundamental challenges in image guided system is to accurately register the preoperative radiological data to the intraoperative anatomical structure of the patient. In this paper, we present a combined surface and fiducial based registration method to register the preoperative 3D CT data to the intraoperative surface of larynx. To accurately model the exposed surface area, a structured light based stereo vision technique is used for the surface reconstruction. We combined the gray code pattern and multi-line shifting to generate the intraoperative surface of the larynx. To register the point clouds from the intraoperative stage to the preoperative 3D CT data, a shape priori based ICP method is proposed to quickly register the two surfaces. The proposed approach is capable of tracking the fiducial markers and reconstructing the surface of larynx with no damage to the anatomical structure. We used off-the-shelf digital cameras, LCD projector and rapid 3D prototyper to develop our experimental system. The final RMS error in the registration is less than 1mm.

Against the odds: foster carers' perceptions of family, commitment and belonging in successful placements.

Science.gov (United States)

Oke, Nicholas; Rostill-Brookes, Helen; Larkin, Michael

2013-01-01

This study examines carer attributes associated with placement stability for teenagers growing up in long term foster care, focusing on unexpected placement success. We explored experiences and perceptions relating to family, belonging and commitment in a group of foster carers providing a stable placement for a young person who had not been expected to settle. These placements showed positive outcome, despite factors in the child's history that might have predicted otherwise. Seven foster carers were interviewed following a semi-structured guide, which covered their ideas about their relationship with the child in question, about the foster family, and the child's sense of belonging in foster and birth family. Analysis of carers' accounts of placements which had succeeded 'against the odds' revealed four major themes, described under the headings My Child--emotional bonding, the carers' enlarged view of family and their parental regard for the young person; Jam in the Sandwich--working within a 'compromised space' between Local Authority and birth family; Repair and Rebuild--the craft of fostering including managing the foster/birth family boundary; Sticking with It--resilience, tenacity and maintaining hopefulness. The carers' accounts offer pointers towards the ingredients of successful placements and prompt reflection on how these may be supported and promoted. They also highlight tensions inherent in the foster carer task relating to carers' parental functioning for young people in long-term foster care.

Post-General Anesthesia Ultrasound-Guided Venous Mapping Increases Autogenous Access Placement Rates.

Science.gov (United States)

Png, C Y Maximilian; Korayem, Adam; Finlay, David J

2018-04-18

between the groups in terms of outpatient vein mapping plans (P=0.10), however when comparing the PAUS plans to the outpatient vein mapping plans, there was again a significantly increased proportion of preferred access types in the PAUS group compared to the outpatient group (P<0.001). In the ordinal logit multivariate analysis, the only significant variable was the post-anesthesia ultrasound, which positively correlated with more favorable access configurations (coefficient=2.61, P<0.001). The bivariate logit regression for autogenous access maturation rates found no significant difference between the without-PAUS group and the PAUS group (P=0.13). Introducing a post-anesthesia ultrasound mapping to guide vein-finding significantly increases the quality and quantity of suitable veins found, subsequently leading to increased proportions preferred access placement (autogenous vs. prosthetic and forearm vs. upper extremity). Copyright © 2018 Elsevier Inc. All rights reserved.

Spectral CT with metal artifacts reduction software for improvement of tumor visibility in the vicinity of gold fiducial markers.

Science.gov (United States)

Brook, Olga R; Gourtsoyianni, Sofia; Brook, Alexander; Mahadevan, Anand; Wilcox, Carol; Raptopoulos, Vassilios

2012-06-01

To evaluate spectral computed tomography (CT) with metal artifacts reduction software (MARS) for reduction of metal artifacts associated with gold fiducial seeds. Thirteen consecutive patients with 37 fiducial seeds implanted for radiation therapy of abdominal lesions were included in this HIPAA-compliant, institutional review board-approved prospective study. Six patients were women (46%) and seven were men (54%). The mean age was 61.1 years (median, 58 years; range, 29-78 years). Spectral imaging was used for arterial phase CT. Images were reconstructed with and without MARS in axial, coronal, and sagittal planes. Two radiologists independently reviewed reconstructions and selected the best image, graded the visibility of the tumor, and assessed the amount of artifacts in all planes. A linear-weighted κ statistic and Wilcoxon signed-rank test were used to assess interobserver variability. Histogram analysis with the Kolmogorov-Smirnov test was used for objective evaluation of artifacts reduction. Fiducial seeds were placed in pancreas (n = 5), liver (n = 7), periportal lymph nodes (n = 1), and gallbladder bed (n = 1). MARS-reconstructed images received a better grade than those with standard reconstruction in 60% and 65% of patients by the first and second radiologist, respectively. Tumor visibility was graded higher with standard versus MARS reconstruction (grade, 3.7 ± 1.0 vs 2.8 ± 1.1; P = .001). Reduction of blooming was noted on MARS-reconstructed images (P = .01). Amount of artifacts, for both any and near field, was significantly smaller on sagittal and coronal MARS-reconstructed images than on standard reconstructions (P MARS-reconstructed images than on standard reconstructions (P MARS than with standard reconstruction in 35 of 37 patients (P MARS improved tumor visibility in the vicinity of gold fiducial seeds.

Comparison of bougie-guided insertion of Proseal tm laryngeal mask airway with digital technique in adults

Directory of Open Access Journals (Sweden)

Anand Kuppusamy

2010-01-01

Full Text Available The Proseal TM laryngeal mask airway (PLMA TM , Laryngeal Mask Company, UK was designed to improve ventilatory characteristics and offer protection against regurgitation and gastric insufflation. The PLMA is a modified laryngeal mask airway with large ventral cuff, dorsal cuff and a drain tube. These modifications improve seal around glottis and enable better ventilatory characteristics. The drain tube prevents gastric distension and offers protection against aspiration. There were occasional problems, like failed insertion and inadequate ventilation, in placing PLMA TM using the classical digital technique. To overcome these problems, newer placement techniques like thumb insertion technique, introducer tool placement and gum elastic bougie (GEB-aided placement were devised. We compared classical digital placement of PLMA TM with gum elastic bougie-aided technique in 60 anaesthetised adult patients (with 30 patients in each group with respect to number of attempts to successful placement, effective airway time, airway trauma during insertion, postoperative airway morbidity and haemodynamic response to insertion. The number of attempts to successful placement, airway trauma during insertion and haemodynamic response to insertion were comparable among the two groups, while effective airway time and oropharyngeal leak pressure were significantly higher in bougie- guided insertion of PLMA. Postoperatively, sore throat was more frequent with digital technique while dysphagia was more frequent with bougie-guided technique. Hence gum elastic bougie guided, laryngoscope aided insertion of PLMA is an excellent alternate to classical digital technique.

The process and challenges of obtaining and sustaining clinical placements for nursing and allied health students.

Science.gov (United States)

Taylor, Christine; Angel, Liz; Nyanga, Lucy; Dickson, Cathy

2017-10-01

To describe the process and challenges from a project that aimed to develop processes, source new placements and place students primarily in the discipline of nursing, but also occupational therapy, physiotherapy, podiatry, social work, and speech therapy. Clinical experience in health facilities is an essential element of health professional education, yet globally, there is a lack of clinical placements to meet demands. Educational providers are seeking placements in nontraditional facilities, yet little has been reported on the challenges in the process of procuring clinical placements. The project used a descriptive approach within a quality implementation framework. The project was guided by the quality implementation framework that included four critical steps: considerations of the host setting, structuring the implementation, supporting the implementation and improving future applications. A total of 115 new student placements were finalised across six health disciplines, including elderly care, nongovernment organisations and general practice. Sixty-two nursing students were placed in the new placements during the project. Challenges included communication, the time-consuming nature of the process and 'gatekeeping' blocks to obtaining placements. Recommendations included the importance of personal interaction in developing and maintaining relationships, and the need for clear communication processes and documentation. Potential areas for research are also given. There is great potential for growth in establishing new placements outside the traditional placement facilities for nursing and allied health and for expanding already existing nonhospital placements. Clinical professional experiences are essential to any nursing or allied health programme. There is an increasing demand for, and global lack of, clinical placements for nursing and allied health students. The results provide nursing and allied health educators and managers a framework for planning

Evaluation of an infrared camera and X-ray system using implanted fiducials in patients with lung tumors for gated radiation therapy

International Nuclear Information System (INIS)

Willoughby, Twyla R.; Forbes, Alan R.; Buchholz, Daniel; Langen, Katja M.; Wagner, Thomas H.; Zeidan, Omar A.; Kupelian, Patrick A.; Meeks, Sanford L.

2006-01-01

Purpose: To report on the initial clinical use of a commercially available system to deliver gated treatment using implanted fiducials, in-room kV X-rays, and an infrared camera tracking system. Methods and Materials: ExacTrac Adaptive Gating from BrainLab is a localization system using infrared cameras and X-rays. Gating signals are the patient's breathing pattern obtained from infrared reflectors on the patient. kV X-rays of an implanted fiducial are synchronized to the breathing pattern. After localization and shift of the patient to isocenter, the breathing pattern is used to gate Radiation. Feasibility tests included localization accuracy, radiation output constancy, and dose distributions with gating. Clinical experience is reported on treatment of patients with small lung lesions. Results: Localization accuracy of a moving target with gating was 1.7 mm. Dose constancy measurements showed insignificant change in output with gating. Improvements of dose distributions on moving targets improved with gating. Eleven patients with lung lesions were implanted with 20 mm x 0.7 mm gold coil (Visicoil). The implanted fiducial was used to localize and treat the patients with gating. Treatment planning and repeat computed tomographic scans showed that the change in center of gross target volume (GTV) to implanted marker averaged 2.47 mm due in part to asymmetric tumor shrinkage. Conclusion: ExacTrac Adaptive Gating has been used to treat lung lesions. Initial system evaluation verified its accuracy and usability. Implanted fiducials are visible in X-rays and did not migrate

A Meta-Analysis of Bilateral Essure® Procedural Placement Success Rates on First Attempt.

Science.gov (United States)

Frietze, Gabriel; Leyser-Whalen, Ophra; Rahman, Mahbubur; Rouhani, Mahta; Berenson, Abbey B

2015-12-01

Background: The Essure ® (Bayer HealthCare Pharmaceuticals, Leverkusen, Germany) female sterilization procedure entails using a hysteroscope to guide a microinsert into the Fallopian tube openings. Failed placement can lead to patient dissatisfaction, repeat procedures, unintended or ectopic pregnancy, perforation of internal organs, or need for subsequent medical interventions. Additional interventions increase women's health risks, and costs for patients and the health care industry. Demonstrated successful placement rates are 63%-100%. To date, there have not been any systematic analyses of variables associated with placement rates. Objectives: The aims of this review were: (1) to estimate the average rate of successful bilateral Essure microinsert placement on first attempt; and (2) to identify variables associated with successful placement. Materials and Methods: A meta-analysis was conducted on 64 published studies and 19 variables. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, all published studies between November 2001 and February 2015 were reviewed. The studies were taken from from PubMed and Google Scholar, and by using the the "snowball" method that reported variables associated with successful bilateral Essure placement rates. Results: The weighted average rate of successful bilateral microinsert placement on first attempt was 92% (0.92 [95% confidence interval: 0.904-0.931]). Variables associated with successful placements were: (1) newer device models; (2) higher body mass index; and (3) a higher percent of patients who received local anesthesia. Conclusions: The data gathered for this review indicate that the highest bilateral success rates may be obtained by utilizing the newest Essure device model with local anesthesia in heavier patients. More standardized data reporting in published Essure studies is recommended. (J GYNECOL SURG 31:308).

SU-F-P-42: “To Navigate, Or Not to Navigate: HDR BT in Recurrent Spine Lesions”

Energy Technology Data Exchange (ETDEWEB)

Voros, L; Cohen, G; Zaider, M; Yamada, Y [Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

2016-06-15

Purpose: We compare the accuracy of HDR catheter placement for paraspinal lesions using O-arm CBCT imaging combined with StealthStation navigation and traditional fluoroscopically guided catheter placement. Methods: CT and MRI scans were acquired pre-treatment to outline the lesions and design treatment plans (pre-plans) to meet dosimetric constrains. The pre-planned catheter trajectories were transferred into the StealthStation Navigation system prior to the surgery. The StealthStation is an infra red (IR) optical navigation system used for guidance of surgical instruments. An intraoperative CBCT scan (O-arm) was acquired with reference IR optical fiducials anchored onto the patient and registered with the preplan image study to guide surgical instruments in relation to the patients’ anatomy and to place the brachytherapy catheters along the pre-planned trajectories. The final treatment plan was generated based on a 2nd intraoperative CBCT scan reflecting achieved implant geometry. The 2nd CBCT was later registered with the initial CT scan to compare the preplanned dwell positions with actual dwell positions (catheter placements). Similar workflow was used in placement of 8 catheters (1 patient) without navigation, but under fluoroscopy guidance in an interventional radiology suite. Results: A total of 18 catheters (3 patients) were placed using navigation assisted surgery. Average displacement of 0.66 cm (STD=0.37cm) was observed between the pre-plan source positions and actual source positions in the 3 dimensional space. This translates into an average 0.38 cm positioning error in one direction including registration errors, digitization errors, and the surgeons ability to follow the planned trajectory. In comparison, average displacement of non-navigated catheters was 0.50 cm (STD=0.22cm). Conclusion: Spinal lesion HDR brachytherapy planning is a difficult task. Catheter placement has a direct impact on target coverage and dose to critical structures. While

Retrospective Analysis of the Accuracy of Ultrasound-Guided Magnetic Resonance Arthrogram Injections of the Hip in the Office Setting.

Science.gov (United States)

Jernick, Michael; Walker Gallego, Edward; Nuzzo, Michael

2017-12-01

Ultrasound (US)-guided intra-articular hip injections have been proposed in the literature to be accurate, reliable, and safe alternatives to fluoroscopy-guided injections. To evaluate the accuracy of US-guided magnetic resonance (MR) arthrogram injections of the hip performed in the office setting by a single orthopaedic surgeon and elucidate the potential effects that patient age, sex, and body mass index (BMI) have on contrast placement. Case series; Level of evidence, 4. From a review of the senior author's office database, 89 patients (101 hips) who had US-guided MR arthrogram injections performed between December 2014 and June 2016 were identified. Official radiology reports were evaluated to determine whether extra-articular contrast was noted. Patient variables, including BMI, age, and sex, were evaluated between patients who had inappropriately placed contrast and those who did not. Of the 101 hip injections, there were 6 cases that demonstrated inadequate contrast placement within the joint, likely secondary to extravasation or incorrect placement; however, an MR arthrogram was adequately interpreted in all cases. There were no significant differences noted between those with appropriate versus inappropriate contrast placement when evaluating BMI ( P = .57), age ( P = .33), or sex ( P = .67), and neither group had an adverse event. US-guided injections are safe and accurate alternatives to fluoroscopy-guided injections in the office setting, with 94% accuracy. Furthermore, BMI, age, and sex did not play a statistically significant role among patients with inappropriately placed contrast.

Intra-operative fiducial-based CT/fluoroscope image registration framework for image-guided robot-assisted joint fracture surgery.

Science.gov (United States)

Dagnino, Giulio; Georgilas, Ioannis; Morad, Samir; Gibbons, Peter; Tarassoli, Payam; Atkins, Roger; Dogramadzi, Sanja

2017-08-01

Joint fractures must be accurately reduced minimising soft tissue damages to avoid negative surgical outcomes. To this regard, we have developed the RAFS surgical system, which allows the percutaneous reduction of intra-articular fractures and provides intra-operative real-time 3D image guidance to the surgeon. Earlier experiments showed the effectiveness of the RAFS system on phantoms, but also key issues which precluded its use in a clinical application. This work proposes a redesign of the RAFS's navigation system overcoming the earlier version's issues, aiming to move the RAFS system into a surgical environment. The navigation system is improved through an image registration framework allowing the intra-operative registration between pre-operative CT images and intra-operative fluoroscopic images of a fractured bone using a custom-made fiducial marker. The objective of the registration is to estimate the relative pose between a bone fragment and an orthopaedic manipulation pin inserted into it intra-operatively. The actual pose of the bone fragment can be updated in real time using an optical tracker, enabling the image guidance. Experiments on phantom and cadavers demonstrated the accuracy and reliability of the registration framework, showing a reduction accuracy (sTRE) of about [Formula: see text] (phantom) and [Formula: see text] (cadavers). Four distal femur fractures were successfully reduced in cadaveric specimens using the improved navigation system and the RAFS system following the new clinical workflow (reduction error [Formula: see text], [Formula: see text]. Experiments showed the feasibility of the image registration framework. It was successfully integrated into the navigation system, allowing the use of the RAFS system in a realistic surgical application.

Endoscopic ultrasound elastography for evaluation of lymph nodes and pancreatic masses: a multicenter study.

Science.gov (United States)

Giovannini, Marc; Thomas, Botelberge; Erwan, Bories; Christian, Pesenti; Fabrice, Caillol; Benjamin, Esterni; Geneviève, Monges; Paolo, Arcidiacono; Pierre, Deprez; Robert, Yeung; Walter, Schimdt; Hanz, Schrader; Carl, Szymanski; Christoph, Dietrich; Pierre, Eisendrath; Jean-Luc, Van Laethem; Jacques, Devière; Peter, Vilmann; Andrian, Saftoiu

2009-04-07

To evaluate the ability of endoscopic ultrasound (EUS) elastography to distinguish benign from malignant pancreatic masses and lymph nodes. A multicenter study was conducted and included 222 patients who underwent EUS examination with assessment of a pancreatic mass (n = 121) or lymph node (n = 101). The classification as benign or malignant, based on the real time elastography pattern, was compared with the classification based on the B-mode EUS images and with the final diagnosis obtained by EUS-guided fine needle aspiration (EUS-FNA) and/or by surgical pathology. An interobserver study was performed. The sensitivity and specificity of EUS elastography to differentiate benign from malignant pancreatic lesions are 92.3% and 80.0%, respectively, compared to 92.3% and 68.9%, respectively, for the conventional B-mode images. The sensitivity and specificity of EUS elastography to differentiate benign from malignant lymph nodes was 91.8% and 82.5%, respectively, compared to 78.6% and 50.0%, respectively, for the B-mode images. The kappa coefficient was 0.785 for the pancreatic masses and 0.657 for the lymph nodes. EUS elastography is superior compared to conventional B-mode imaging and appears to be able to distinguish benign from malignant pancreatic masses and lymph nodes with a high sensitivity, specificity and accuracy. It might be reserved as a second line examination to help characterise pancreatic masses after negative EUS-FNA and might increase the yield of EUS-FNA for lymph nodes.

Resection of deep-seated gliomas using neuroimaging for stereotactic placement of guidance catheters

Energy Technology Data Exchange (ETDEWEB)

Matsumoto, Kengo; Higashi, Hisato; Tomita, Susumu; Furuta, Tomohisa; Ohmoto, Takashi [Okayama Univ. (Japan). School of Medicine

1995-03-01

A simple computed tomography- (CT) or magnetic resonance (MR) imaging-guided stereotactic method for guided microsurgical resection of either deep-seated gliomas or tumors adjacent to an eloquent area is described. The technique employs the Brown-Roberts-Wells stereotactic system and twist drills, 2.7 mm in diameter, for the stereotactic placement of 2.4 mm diameter scaled guidance catheters through the calvaria. In a patient with a deep-seated small glioma, less than 2 cm diameter, one catheter was implanted into the center of the enhanced mass through the cerebral cortex. In the other 14 patients, three to six catheters were used which made the tumor border clearer. After implantation of the guidance catheters, the stereotactic frame was removed and a standard open craniotomy performed. Target localization is not affected by brain movement, which is inevitable during open surgery. The tumor involved the frontal lobe in eight patients, the parietal lobe in two, and the thalamus in five. In all cases the lesion was quickly localized and radical removal was acheived. Neurological complications occurred in only one patient who suffered transient hemiparesis after the resection of a lesion in the pyramidal tract. The results demonstrate that microsurgery combined with CT- or MR imaging-guided stereotactic placement of guidance catheters is a new option for surgery of deep-seated gliomas or tumors adjacent to an eloquent area. (author).

Image-Guided Radiotherapy in Near Real Time With Intensity-Modulated Radiotherapy Megavoltage Treatment Beam Imaging

International Nuclear Information System (INIS)

Mao Weihua; Hsu, Annie; Riaz, Nadeem; Lee, Louis; Wiersma, Rodney; Luxton, Gary; King, Christopher; Xing Lei; Solberg, Timothy

2009-01-01

Purpose: To utilize image-guided radiotherapy (IGRT) in near real time by obtaining and evaluating the online positions of implanted fiducials from continuous electronic portal imaging device (EPID) imaging of prostate intensity-modulated radiotherapy (IMRT) delivery. Methods and Materials: Upon initial setup using two orthogonal images, the three-dimensional (3D) positions of all implanted fiducial markers are obtained, and their expected two-dimensional (2D) locations in the beam's-eye-view (BEV) projection are calculated for each treatment field. During IMRT beam delivery, EPID images of the megavoltage treatment beam are acquired in cine mode and subsequently analyzed to locate 2D locations of fiducials in the BEV. Simultaneously, 3D positions are estimated according to the current EPID image, information from the setup portal images, and images acquired at other gantry angles (the completed treatment fields). The measured 2D and 3D positions of each fiducial are compared with their expected 2D and 3D setup positions, respectively. Any displacements larger than a predefined tolerance may cause the treatment system to suspend the beam delivery and direct the therapists to reposition the patient. Results: Phantom studies indicate that the accuracy of 2D BEV and 3D tracking are better than 1 mm and 1.4 mm, respectively. A total of 7330 images from prostate treatments were acquired and analyzed, showing a maximum 2D displacement of 6.7 mm and a maximum 3D displacement of 6.9 mm over 34 fractions. Conclusions: This EPID-based, real-time IGRT method can be implemented on any external beam machine with portal imaging capabilities without purchasing any additional equipment, and there is no extra dose delivered to the patient.

Incorporation of a laser range scanner into image-guided liver surgery: Surface acquisition, registration, and tracking

OpenAIRE

Cash, David M.; Sinha, Tuhin K.; Chapman, William C.; Terawaki, Hiromi; Dawant, Benoit M.; Galloway, Robert L.; Miga, Michael I.

2003-01-01

As image guided surgical procedures become increasingly diverse, there will be more scenarios where point-based fiducials cannot be accurately localized for registration and rigid body assumptions no longer hold. As a result, procedures will rely more frequently on anatomical surfaces for the basis of image alignment and will require intraoperative geometric data to measure and compensate for tissue deformation in the organ. In this paper we outline methods for which a laser range scanner may...

Validation of deformable image registration algorithms on CT images of ex vivo porcine bladders with fiducial markers

Energy Technology Data Exchange (ETDEWEB)

Wognum, S., E-mail: s.wognum@gmail.com; Heethuis, S. E.; Bel, A. [Department of Radiation Oncology, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam (Netherlands); Rosario, T. [Department of Radiation Oncology, VU University Medical Center, De Boelelaan 1117, 1081 HZ Amsterdam (Netherlands); Hoogeman, M. S. [Department of Radiation Oncology, Erasmus MC Cancer Institute, Erasmus Medical Center, Groene Hilledijk 301, 3075 EA Rotterdam (Netherlands)

2014-07-15

Purpose: The spatial accuracy of deformable image registration (DIR) is important in the implementation of image guided adaptive radiotherapy techniques for cancer in the pelvic region. Validation of algorithms is best performed on phantoms with fiducial markers undergoing controlled large deformations. Excised porcine bladders, exhibiting similar filling and voiding behavior as human bladders, provide such an environment. The aim of this study was to determine the spatial accuracy of different DIR algorithms on CT images ofex vivo porcine bladders with radiopaque fiducial markers applied to the outer surface, for a range of bladder volumes, using various accuracy metrics. Methods: Five excised porcine bladders with a grid of 30–40 radiopaque fiducial markers attached to the outer wall were suspended inside a water-filled phantom. The bladder was filled with a controlled amount of water with added contrast medium for a range of filling volumes (100–400 ml in steps of 50 ml) using a luer lock syringe, and CT scans were acquired at each filling volume. DIR was performed for each data set, with the 100 ml bladder as the reference image. Six intensity-based algorithms (optical flow or demons-based) implemented in theMATLAB platform DIRART, a b-spline algorithm implemented in the commercial software package VelocityAI, and a structure-based algorithm (Symmetric Thin Plate Spline Robust Point Matching) were validated, using adequate parameter settings according to values previously published. The resulting deformation vector field from each registration was applied to the contoured bladder structures and to the marker coordinates for spatial error calculation. The quality of the algorithms was assessed by comparing the different error metrics across the different algorithms, and by comparing the effect of deformation magnitude (bladder volume difference) per algorithm, using the Independent Samples Kruskal-Wallis test. Results: The authors found good structure

Validation of deformable image registration algorithms on CT images of ex vivo porcine bladders with fiducial markers.

Science.gov (United States)

Wognum, S; Heethuis, S E; Rosario, T; Hoogeman, M S; Bel, A

2014-07-01

The spatial accuracy of deformable image registration (DIR) is important in the implementation of image guided adaptive radiotherapy techniques for cancer in the pelvic region. Validation of algorithms is best performed on phantoms with fiducial markers undergoing controlled large deformations. Excised porcine bladders, exhibiting similar filling and voiding behavior as human bladders, provide such an environment. The aim of this study was to determine the spatial accuracy of different DIR algorithms on CT images of ex vivo porcine bladders with radiopaque fiducial markers applied to the outer surface, for a range of bladder volumes, using various accuracy metrics. Five excised porcine bladders with a grid of 30-40 radiopaque fiducial markers attached to the outer wall were suspended inside a water-filled phantom. The bladder was filled with a controlled amount of water with added contrast medium for a range of filling volumes (100-400 ml in steps of 50 ml) using a luer lock syringe, and CT scans were acquired at each filling volume. DIR was performed for each data set, with the 100 ml bladder as the reference image. Six intensity-based algorithms (optical flow or demons-based) implemented in theMATLAB platform DIRART, a b-spline algorithm implemented in the commercial software package VelocityAI, and a structure-based algorithm (Symmetric Thin Plate Spline Robust Point Matching) were validated, using adequate parameter settings according to values previously published. The resulting deformation vector field from each registration was applied to the contoured bladder structures and to the marker coordinates for spatial error calculation. The quality of the algorithms was assessed by comparing the different error metrics across the different algorithms, and by comparing the effect of deformation magnitude (bladder volume difference) per algorithm, using the Independent Samples Kruskal-Wallis test. The authors found good structure accuracy without dependency on

Validation of deformable image registration algorithms on CT images of ex vivo porcine bladders with fiducial markers

International Nuclear Information System (INIS)

Wognum, S.; Heethuis, S. E.; Bel, A.; Rosario, T.; Hoogeman, M. S.

2014-01-01

Purpose: The spatial accuracy of deformable image registration (DIR) is important in the implementation of image guided adaptive radiotherapy techniques for cancer in the pelvic region. Validation of algorithms is best performed on phantoms with fiducial markers undergoing controlled large deformations. Excised porcine bladders, exhibiting similar filling and voiding behavior as human bladders, provide such an environment. The aim of this study was to determine the spatial accuracy of different DIR algorithms on CT images ofex vivo porcine bladders with radiopaque fiducial markers applied to the outer surface, for a range of bladder volumes, using various accuracy metrics. Methods: Five excised porcine bladders with a grid of 30–40 radiopaque fiducial markers attached to the outer wall were suspended inside a water-filled phantom. The bladder was filled with a controlled amount of water with added contrast medium for a range of filling volumes (100–400 ml in steps of 50 ml) using a luer lock syringe, and CT scans were acquired at each filling volume. DIR was performed for each data set, with the 100 ml bladder as the reference image. Six intensity-based algorithms (optical flow or demons-based) implemented in theMATLAB platform DIRART, a b-spline algorithm implemented in the commercial software package VelocityAI, and a structure-based algorithm (Symmetric Thin Plate Spline Robust Point Matching) were validated, using adequate parameter settings according to values previously published. The resulting deformation vector field from each registration was applied to the contoured bladder structures and to the marker coordinates for spatial error calculation. The quality of the algorithms was assessed by comparing the different error metrics across the different algorithms, and by comparing the effect of deformation magnitude (bladder volume difference) per algorithm, using the Independent Samples Kruskal-Wallis test. Results: The authors found good structure

MR-guided direct arthrography of the glenohumeral joint

International Nuclear Information System (INIS)

Soh, E.; Bearcroft, P.W.P.; Graves, M.J.; Black, R.; Lomas, D.J.

2008-01-01

Aim: To evaluate the feasibility of magnetic resonance (MR)-guided direct arthrography of the glenohumeral joint with a 1.5 T MR system, performing the entire procedure in a single MR examination. Materials and methods: MR-guided direct arthrography was performed on 11 patients. MR imaging guidance and interactive MR fluoroscopy, with in-room control and display system, were used for needle placement and contrast medium injection. The outcome measures were success or failure of joint puncture, the time taken for introduction of contrast medium, and the diagnostic quality of the subsequent MR arthrography images. Results: Contrast medium was successfully instilled into the joint and diagnostic quality MR arthrography images were obtained in all cases. The median time from initial placement of the skin marker to introduction of the contrast medium was 17 min (range 11-29 min). There were no immediate post-procedure complications. Conclusion: Accurate needle placement is feasible in a single MR examination on a commercial 1.5 T closed-bore MR system, using an in-room control and display system together with interactive fluoroscopic imaging, and this was used to provide direct MR arthrography in this study

Radiologic placement of Hickman catheters

International Nuclear Information System (INIS)

Robertson, L.J.; Mauro, M.A.; Jaques, P.F.

1988-01-01

Hickman catheter inserter has previously been predominantly accomplished surgically by means of venous cutdown or percutaneous placement in the operating room. The authors describe their method and results for 55 consecutive percutaneous placements of Hickman catheters in the interventional radiology suite. Complication rates were comparable to those for surgical techniques. Radiologic placement resulted in increased convenience, decreased time and cost of insertion, and super fluoroscopic control of catheter placement and any special manipulations. Modern angiographic materials provide safer access to the subclavian vein than traditional methods. The authors conclude that radiologic placement of Hickman catheters offers significant advantages over traditional surgical placement

Supporting Student Nurses Learning in and through Clinical Practice: The Role of the Clinical Guide.

Science.gov (United States)

Andrews, Margaret; Roberts, Debbie

2003-01-01

A clinical guide is an experienced nurse who supports nursing students throughout the program, particularly in clinical placements. More than a mentor, a guide is fully involved in promoting deep learning in clinical settings. (SK)

Accuracy of heart rate variability estimation by photoplethysmography using an smartphone: Processing optimization and fiducial point selection.

Science.gov (United States)

Ferrer-Mileo, V; Guede-Fernandez, F; Fernandez-Chimeno, M; Ramos-Castro, J; Garcia-Gonzalez, M A

2015-08-01

This work compares several fiducial points to detect the arrival of a new pulse in a photoplethysmographic signal using the built-in camera of smartphones or a photoplethysmograph. Also, an optimization process for the signal preprocessing stage has been done. Finally we characterize the error produced when we use the best cutoff frequencies and fiducial point for smartphones and photopletysmograph and compare if the error of smartphones can be reasonably be explained by variations in pulse transit time. The results have revealed that the peak of the first derivative and the minimum of the second derivative of the pulse wave have the lowest error. Moreover, for these points, high pass filtering the signal between 0.1 to 0.8 Hz and low pass around 2.7 Hz or 3.5 Hz are the best cutoff frequencies. Finally, the error in smartphones is slightly higher than in a photoplethysmograph.

Accuracy of Ultrasound-Based (BAT) Prostate-Repositioning: A Three-Dimensional On-Line Fiducial-Based Assessment With Cone-Beam Computed Tomography

International Nuclear Information System (INIS)

Boda-Heggemann, Judit; Koehler, Frederick Marc; Kuepper, Beate; Wolff, Dirk; Wertz, Hansjoerg; Mai, Sabine; Hesser, Juergen; Lohr, Frank; Wenz, Frederik

2008-01-01

Purpose: To assess the accuracy of ultrasound-based repositioning (BAT) before prostate radiation with fiducial-based three-dimensional matching with cone-beam computed tomography (CBCT). Patients and Methods: Fifty-four positionings in 8 patients with 125 I seeds/intraprostatic calcifications as fiducials were evaluated. Patients were initially positioned according to skin marks and after this according to bony structures based on CBCT. Prostate position correction was then performed with BAT. Residual error after repositioning based on skin marks, bony anatomy, and BAT was estimated by a second CBCT based on user-independent automatic fiducial registration. Results: Overall mean value (MV ± SD) residual error after BAT based on fiducial registration by CBCT was 0.7 ± 1.7 mm in x (group systematic error [M] = 0.5 mm; SD of systematic error [Σ] = 0.8 mm; SD of random error [σ] = 1.4 mm), 0.9 ± 3.3 mm in y (M = 0.5 mm, Σ = 2.2 mm, σ = 2.8 mm), and -1.7 ± 3.4 mm in z (M = -1.7 mm, Σ = 2.3 mm, σ = 3.0 mm) directions, whereas residual error relative to positioning based on skin marks was 2.1 ± 4.6 mm in x (M = 2.6 mm, Σ = 3.3 mm, σ = 3.9 mm), -4.8 ± 8.5 mm in y (M = -4.4 mm, Σ = 3.7 mm, σ = 6.7 mm), and -5.2 ± 3.6 mm in z (M = -4.8 mm, Σ = 1.7 mm, σ = 3.5mm) directions and relative to positioning based on bony anatomy was 0 ± 1.8 mm in x (M = 0.2 mm, Σ = 0.9 mm, σ = 1.1 mm), -3.5 ± 6.8 mm in y (M = -3.0 mm, Σ = 1.8 mm, σ = 3.7 mm), and -1.9 ± 5.2 mm in z (M = -2.0 mm, Σ = 1.3 mm, σ = 4.0 mm) directions. Conclusions: BAT improved the daily repositioning accuracy over skin marks or even bony anatomy. The results obtained with BAT are within the precision of extracranial stereotactic procedures and represent values that can be achieved with several users with different education levels. If sonographic visibility is insufficient, CBCT or kV/MV portal imaging with implanted fiducials are recommended

Evaluating the Effects of Basic Skills Mathematics Placement on Academic Outcomes of Community College Students

Science.gov (United States)

Melguizo, Tatiana; Bo, Hans; Prather, George; Kim, Bo

2011-01-01

The main objective of the authors' proposed study is to evaluate the effectiveness of math placement policies for entering community college students on these students' academic success in math, and their transfer and graduation rates. The main research question that guides the proposed study is: What are the effects of various basic skills…

Endoscopic ultrasound guided radiofrequency ablation, for pancreatic cystic neoplasms and neuroendocrine tumors

Science.gov (United States)

Pai, Madhava; Habib, Nagy; Senturk, Hakan; Lakhtakia, Sundeep; Reddy, Nageshwar; Cicinnati, Vito R; Kaba, Iyad; Beckebaum, Susanne; Drymousis, Panagiotis; Kahaleh, Michel; Brugge, William

2015-01-01

AIM: To outline the feasibility, safety, adverse events and early results of endoscopic ultrasound (EUS)-radiofrequency ablation (RFA) in pancreatic neoplasms using a novel probe. METHODS: This is a multi-center, pilot safety feasibility study. The intervention described was radiofrequency ablation (RF) which was applied with an innovative monopolar RF probe (1.2 mm Habib EUS-RFA catheter) placed through a 19 or 22 gauge fine needle aspiration (FNA) needle once FNA was performed in patients with a tumor in the head of the pancreas. The Habib™ EUS-RFA is a 1 Fr wire (0.33 mm, 0.013”) with a working length of 190 cm, which can be inserted through the biopsy channel of an echoendoscope. RF power is applied to the electrode at the end of the wire to coagulate tissue in the liver and pancreas. RESULTS: Eight patients [median age of 65 (range 27-82) years; 7 female and 1 male] were recruited in a prospective multicenter trial. Six had a pancreatic cystic neoplasm (four a mucinous cyst, one had intraductal papillary mucinous neoplasm and one a microcystic adenoma) and two had a neuroendocrine tumors (NET) in the head of pancreas. The mean size of the cystic neoplasm and NET were 36.5 mm (SD ± 17.9 mm) and 27.5 mm (SD ± 17.7 mm) respectively. The EUS-RFA was successfully completed in all cases. Among the 6 patients with a cystic neoplasm, post procedure imaging in 3-6 mo showed complete resolution of the cysts in 2 cases, whilst in three more there was a 48.4% reduction [mean pre RF 38.8 mm (SD ± 21.7 mm) vs mean post RF 20 mm (SD ± 17.1 mm)] in size. In regards to the NET patients, there was a change in vascularity and central necrosis after EUS-RFA. No major complications were observed within 48 h of the procedure. Two patients had mild abdominal pain that resolved within 3 d. CONCLUSION: EUS-RFA of pancreatic neoplasms with a novel monopolar RF probe was well tolerated in all cases. Our preliminary data suggest that the procedure is straightforward and safe. The

Percutaneous catheter drainage of thoracic fluid: the usefulness and safety of bedside trocar placement under ultrasound guidance

Energy Technology Data Exchange (ETDEWEB)

Lee, Heon [Seoul Medical Center, Seoul (Korea, Republic of)

2006-07-15

The author wanted to evaluate the usefulness and safety of the trocar technique for US-guided bedside catheter placement into thoracic fluid collections, and this technique has generally been reserved for the larger or superficial fluid collections. 42 drainage procedures were performed in 38 patients at the bedside. The patients were positioned supine or semi-upright. A drainage catheter system with a stylet and cannula assembly was used and all of the catheters were inserted using the trocar technique. The procedures consisted of drainage of empyema (n=14), malignant effusion (n=13), lung abscess (n=3), massive transudate (n=8), hemothorax (n=2) and chest wall hematoma (n=2). The clinical results were classified as successful (complete and partially successful), failure or undetermined. The medical records and images were retrospectively reviewed to evaluate the success rate, the complications and the procedure time. Technical success was achieved in all of the 42 procedures. With using the trocar technique, all the catheters were placed into even the small collections without significant complications. Drainage was successful in 36 (85.7%) of the 42 procedures. The average volume of thoracic fluid that was aspirated manually at the time of catheter placement was 420 mL (range: 35 to 1470 mL). The procedure time was less than 10 minutes from US-localization to complete catheter placement in all of the procedures. The trocar technique under US guidance can be an efficient and safe alternative to the Seldinger or guide-wire exchange technique for bedside catheter placement in the critically ill or hemodynamically unstable patients.

Placement of acid spoil materials

Energy Technology Data Exchange (ETDEWEB)

Pionke, H B; Rogowski, A S

1982-06-01

Potentially there are several chemical and hydrologic problems associated with placement of acid spoil materials. The rationale for a deep placement well below the soil surface, and preferably below a water table, is to prevent or minimize oxidation of pyrite to sulfuric acid and associated salts by reducing the supply of oxygen. If, however, substantial sulfuric acid or associated salts are already contained within the spoil because of present or previous mining, handling and reclamation operations (or if large supplies of indigenous salts exist, placement below a water table) may actually increase the rate of acid and salt leaching. Specific placement of acid- and salt-containing spoil should be aimed at preventing contact with percolating water or rising water tables. We recommend placement based on chemical and physical spoil properties that may affect water percolation O/sub 2/ diffusion rates in the profile. Both the deeper placement of acid spoil and coarser particle size can substantially reduce the amount of acid drainage. Placement above the water table with emphasis on percolate control may be better for high sulfate spoils, while placement below the non-fluctuating water table may be better for pyritic spoils.

Reliable and valid assessment of competence in endoscopic ultrasonography and fine-needle aspiration for mediastinal staging of non-small cell lung cancer

DEFF Research Database (Denmark)

Konge, Lars; Vilmann, P; Clementsen, P

2012-01-01

Fine-needle aspiration (FNA) guided by endoscopic ultrasonography (EUS) is important in mediastinal staging of non-small cell lung cancer (NSCLC). Training standards and implementation strategies of this technique are currently under discussion. The aim of this study was to explore the reliabilit...... and validity of a newly developed EUS Assessment Tool (EUSAT) designed to measure competence in EUS - FNA for mediastinal staging of NSCLC....

Development of wide area tracking method for augmented reality using multi-range fiducials

International Nuclear Information System (INIS)

Ishii, Hirotake; Fujino, Hidenori; Yan, Weida; Yang, Shoufeng; Shimoda, Hiroshi; Izumi, Masanori

2009-01-01

A new fiducial marker for augmented reality was designed along with a method that recognizes the markers captured by a camera and calculates the relative position and orientation between the markers and the camera. These markers can be used at both long and short distances without increasing the number of markers pasted in the environment. Results of the experimental evaluation show that the new marker can be used in a larger area than circular markers and more stably than square markers. (author)

Entrapment of Guide Wire in an Inferior Vena Cava Filter: A Technique for Removal

International Nuclear Information System (INIS)

Abdel-Aal, Ahmed Kamel; Saddekni, Souheil; Hamed, Maysoon Farouk; Fitzpatrick, Farley

2013-01-01

Entrapment of a central venous catheter (CVC) guide wire in an inferior vena cava (IVC) filter is a rare, but reported complication during CVC placement. With the increasing use of vena cava filters (VCFs), this number will most likely continue to grow. The consequences of this complication can be serious, as continued traction upon the guide wire may result in filter dislodgement and migration, filter fracture, or injury to the IVC. We describe a case in which a J-tipped guide wire introduced through a left subclavian access without fluoroscopic guidance during CVC placement was entrapped at the apex of an IVC filter. We describe a technique that we used successfully in removing the entrapped wire through the left subclavian access site. We also present simple useful recommendations to prevent this complication.

Radiologic Placement of Uncovered Stents for the Treatment of Malignant Colonic Obstruction Proximal to the Descending Colon

Energy Technology Data Exchange (ETDEWEB)

Yoon, Jehong; Kwon, Se Hwan, E-mail: Kwon98@khu.ac.kr [Kyung Hee University, Department of Radiology, College of Medicine (Korea, Republic of); Lee, Chang-Kyun [Kyung Hee University, Department of Internal Medicine, College of Medicine (Korea, Republic of); Park, Sun Jin [Kyung Hee University, Department of Surgery, College of Medicine (Korea, Republic of); Oh, Ji Young [Kyung Hee University Hospital at Gangdong, Department of Radiology (Korea, Republic of); Oh, Joo Hyeong [Kyung Hee University, Department of Radiology, College of Medicine (Korea, Republic of)

2017-01-15

PurposeTo evaluate the safety, feasibility, and patency rates of radiologic placement of uncovered stents for the treatment of malignant colonic obstruction proximal to the descending colon.Materials and MethodsThis was a retrospective, single-center study. From May 2003 to March 2015, 53 image-guided placements of uncovered stents (44 initial placements, 9 secondary placements) were attempted in 44 patients (male:female = 23:21; mean age, 71.8 years). The technical and clinical success, complication rates, and patency rates of the stents were also evaluated. Technical success was defined as the successful deployment of the stent under fluoroscopic guidance alone and clinical success was defined as the relief of obstructive symptoms or signs within 48 h of stent deployment.ResultsIn total, 12 (27.3 %) patients underwent preoperative decompression, while 32 (72.7 %) underwent decompression with palliative intent. The technical success rate was 93.2 % (41/44) for initial placement and 88.9 % (8/9) for secondary placement. Secondary stent placement in the palliative group was required in nine patients after successful initial stent placement due to stent obstruction from tumor ingrowth (n = 7) and stent migration (n = 2). The symptoms of obstruction were relieved in all successful cases (100 %). In the palliative group, the patency rates were 94.4 % at 1 month, 84.0 % at 3 months, 64.8 % at 6 months, and 48.6 % at 12 months.ConclusionsThe radiologic placement of uncovered stents for the treatment of malignant obstruction proximal to the descending colon is feasible and safe, and provides acceptable clinical results.

Increased central common drive to ankle plantar flexor and dorsiflexor muscles during visually guided gait

DEFF Research Database (Denmark)

Jensen, Peter; Jensen, Nicole Jacqueline; Terkildsen, Cecilie Ulbæk

2018-01-01

When we walk in a challenging environment, we use visual information to modify our gait and place our feet carefully on the ground. Here, we explored how central common drive to ankle muscles changes in relation to visually guided foot placement. Sixteen healthy adults aged 23 ± 5 years participa......When we walk in a challenging environment, we use visual information to modify our gait and place our feet carefully on the ground. Here, we explored how central common drive to ankle muscles changes in relation to visually guided foot placement. Sixteen healthy adults aged 23 ± 5 years...

Correlation Theory Applied to the Static and Dynamic Properties of EuO and EuS

DEFF Research Database (Denmark)

Lindgård, Per-Anker

1982-01-01

was used previously in the correlation theory2) primarily to calculate static properties. Self‐consistent dynamic and static calculations have here been performed for EuO, which is an ideal Heisenberg magnet with significant second‐nearest‐neighbor interaction (J2 = J1/5). The two‐pole approximation...... a cutoff of the spectrum at high frequencies, which cannot be seen experimentally, but which significantly influences the frequency moments. It was found that the finite J2 has significant importance for a comparison between theory and experiment. It is concluded that the calculation for a simple cubic n.......n. magnet by Hubbard3) does not describe the EuO data accurately, neither with respect to line shape nor frequency scale. Significant differences are to be expected between EuO and EuS having opposite sign for J2....

Augmented reality-guided neurosurgery: accuracy and intraoperative application of an image projection technique.

Science.gov (United States)

Besharati Tabrizi, Leila; Mahvash, Mehran

2015-07-01

An augmented reality system has been developed for image-guided neurosurgery to project images with regions of interest onto the patient's head, skull, or brain surface in real time. The aim of this study was to evaluate system accuracy and to perform the first intraoperative application. Images of segmented brain tumors in different localizations and sizes were created in 10 cases and were projected to a head phantom using a video projector. Registration was performed using 5 fiducial markers. After each registration, the distance of the 5 fiducial markers from the visualized tumor borders was measured on the virtual image and on the phantom. The difference was considered a projection error. Moreover, the image projection technique was intraoperatively applied in 5 patients and was compared with a standard navigation system. Augmented reality visualization of the tumors succeeded in all cases. The mean time for registration was 3.8 minutes (range 2-7 minutes). The mean projection error was 0.8 ± 0.25 mm. There were no significant differences in accuracy according to the localization and size of the tumor. Clinical feasibility and reliability of the augmented reality system could be proved intraoperatively in 5 patients (projection error 1.2 ± 0.54 mm). The augmented reality system is accurate and reliable for the intraoperative projection of images to the head, skull, and brain surface. The ergonomic advantage of this technique improves the planning of neurosurgical procedures and enables the surgeon to use direct visualization for image-guided neurosurgery.

A Fully Actuated Robotic Assistant for MRI-Guided Prostate Biopsy and Brachytherapy

Science.gov (United States)

Li, Gang; Su, Hao; Shang, Weijian; Tokuda, Junichi; Hata, Nobuhiko; Tempany, Clare M.; Fischer, Gregory S.

2014-01-01

Intra-operative medical imaging enables incorporation of human experience and intelligence in a controlled, closed-loop fashion. Magnetic resonance imaging (MRI) is an ideal modality for surgical guidance of diagnostic and therapeutic procedures, with its ability to perform high resolution, real-time, high soft tissue contrast imaging without ionizing radiation. However, for most current image-guided approaches only static pre-operative images are accessible for guidance, which are unable to provide updated information during a surgical procedure. The high magnetic field, electrical interference, and limited access of closed-bore MRI render great challenges to developing robotic systems that can perform inside a diagnostic high-field MRI while obtaining interactively updated MR images. To overcome these limitations, we are developing a piezoelectrically actuated robotic assistant for actuated percutaneous prostate interventions under real-time MRI guidance. Utilizing a modular design, the system enables coherent and straight forward workflow for various percutaneous interventions, including prostate biopsy sampling and brachytherapy seed placement, using various needle driver configurations. The unified workflow compromises: 1) system hardware and software initialization, 2) fiducial frame registration, 3) target selection and motion planning, 4) moving to the target and performing the intervention (e.g. taking a biopsy sample) under live imaging, and 5) visualization and verification. Phantom experiments of prostate biopsy and brachytherapy were executed under MRI-guidance to evaluate the feasibility of the workflow. The robot successfully performed fully actuated biopsy sampling and delivery of simulated brachytherapy seeds under live MR imaging, as well as precise delivery of a prostate brachytherapy seed distribution with an RMS accuracy of 0.98mm. PMID:25076821

The significance test controversy revisited the fiducial Bayesian alternative

CERN Document Server

Lecoutre, Bruno

2014-01-01

The purpose of this book is not only to revisit the “significance test controversy,”but also to provide a conceptually sounder alternative. As such, it presents a Bayesian framework for a new approach to analyzing and interpreting experimental data. It also prepares students and researchers for reporting on experimental results. Normative aspects: The main views of statistical tests are revisited and the philosophies of Fisher, Neyman-Pearson and Jeffrey are discussed in detail. Descriptive aspects: The misuses of Null Hypothesis Significance Tests are reconsidered in light of Jeffreys’ Bayesian conceptions concerning the role of statistical inference in experimental investigations. Prescriptive aspects: The current effect size and confidence interval reporting practices are presented and seriously questioned. Methodological aspects are carefully discussed and fiducial Bayesian methods are proposed as a more suitable alternative for reporting on experimental results. In closing, basic routine procedures...

Kilovoltage Imaging of Implanted Fiducials to Monitor Intrafraction Motion With Abdominal Compression During Stereotactic Body Radiation Therapy for Gastrointestinal Tumors

Energy Technology Data Exchange (ETDEWEB)

Yorke, Ellen, E-mail: yorke@mskcc.org [Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Xiong, Ying [Department of Radiation Oncology, China-Japan Friendship Hospital, Beijing (China); Han, Qian [Department of Radiotherapy, Henan Provincial People' s Hospital, Zhengzhou (China); Zhang, Pengpeng; Mageras, Gikas; Lovelock, Michael; Pham, Hai; Xiong, Jian-Ping [Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Goodman, Karyn A. [Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York (United States)

2016-07-01

Purpose: To assess intrafraction respiratory motion using a commercial kilovoltage imaging system for abdominal tumor patients with implanted fiducials and breathing constrained by pneumatic compression during stereotactic body radiation therapy (SBRT). Methods and Materials: A pneumatic compression belt limited respiratory motion in 19 patients with radiopaque fiducials in or near their tumor during SBRT for abdominal tumors. Kilovoltage images were acquired at 5- to 6-second intervals during treatment using a commercial system. Intrafractional fiducial displacements were measured using in-house software. The dosimetric effect of the observed displacements was calculated for 3 sessions for each patient. Results: Intrafraction displacement patterns varied between patients and between individual treatment sessions. Averaged over 19 patients, 73 sessions, 7.6% of craniocaudal displacements exceeded 0.5 cm, and 1.2% exceeded 0.75 cm. The calculated single-session dose to 95% of gross tumor volume differed from planned by an average of −1.2% (range, −11.1% to 4.8%) but only for 4 patients was the total 3-session calculated dose to 95% of gross tumor volume more than 3% different from planned. Conclusions: Our pneumatic compression limited intrafractional abdominal target motion, maintained target position established at setup, and was moderately effective in preserving coverage. Commercially available intrafractional imaging is useful for surveillance but can be made more effective and reliable.

Kilovoltage Imaging of Implanted Fiducials to Monitor Intrafraction Motion With Abdominal Compression During Stereotactic Body Radiation Therapy for Gastrointestinal Tumors

International Nuclear Information System (INIS)

Yorke, Ellen; Xiong, Ying; Han, Qian; Zhang, Pengpeng; Mageras, Gikas; Lovelock, Michael; Pham, Hai; Xiong, Jian-Ping; Goodman, Karyn A.

2016-01-01

Purpose: To assess intrafraction respiratory motion using a commercial kilovoltage imaging system for abdominal tumor patients with implanted fiducials and breathing constrained by pneumatic compression during stereotactic body radiation therapy (SBRT). Methods and Materials: A pneumatic compression belt limited respiratory motion in 19 patients with radiopaque fiducials in or near their tumor during SBRT for abdominal tumors. Kilovoltage images were acquired at 5- to 6-second intervals during treatment using a commercial system. Intrafractional fiducial displacements were measured using in-house software. The dosimetric effect of the observed displacements was calculated for 3 sessions for each patient. Results: Intrafraction displacement patterns varied between patients and between individual treatment sessions. Averaged over 19 patients, 73 sessions, 7.6% of craniocaudal displacements exceeded 0.5 cm, and 1.2% exceeded 0.75 cm. The calculated single-session dose to 95% of gross tumor volume differed from planned by an average of −1.2% (range, −11.1% to 4.8%) but only for 4 patients was the total 3-session calculated dose to 95% of gross tumor volume more than 3% different from planned. Conclusions: Our pneumatic compression limited intrafractional abdominal target motion, maintained target position established at setup, and was moderately effective in preserving coverage. Commercially available intrafractional imaging is useful for surveillance but can be made more effective and reliable.

Split-mouth comparison of the accuracy of computer-generated and conventional surgical guides.

Science.gov (United States)

Farley, Nathaniel E; Kennedy, Kelly; McGlumphy, Edwin A; Clelland, Nancy L

2013-01-01

Recent clinical studies have shown that implant placement is highly predictable with computer-generated surgical guides; however, the reliability of these guides has not been compared to that of conventional guides clinically. This study aimed to compare the accuracy of reproducing planned implant positions with computer-generated and conventional surgical guides using a split-mouth design. Ten patients received two implants each in symmetric locations. All implants were planned virtually using a software program and information from cone beam computed tomographic scans taken with scan appliances in place. Patients were randomly selected for computer-aided design/computer-assisted manufacture (CAD/CAM)-guided implant placement on their right or left side. Conventional guides were used on the contralateral side. Patients underwent operative cone beam computed tomography postoperatively. Planned and actual implant positions were compared using three-dimensional analyses capable of measuring volume overlap as well as differences in angles and coronal and apical positions. Results were compared using a mixed-model repeated-measures analysis of variance and were further analyzed using a Bartlett test for unequal variance (α = .05). Implants placed with CAD/CAM guides were closer to the planned positions in all eight categories examined. However, statistically significant differences were shown only for coronal horizontal distances. It was also shown that CAD/CAM guides had less variability than conventional guides, which was statistically significant for apical distance. Implants placed using CAD/CAM surgical guides provided greater accuracy in a lateral direction than conventional guides. In addition, CAD/CAM guides were more consistent in their deviation from the planned locations than conventional guides.

Why good placements matter: Pre-placement and placement risk factors associated with mental health disorders in pre-school children in foster care.

Science.gov (United States)

Hillen, Thomas; Gafson, Leonie

2015-07-01

Pre-school children placed in local authority care show elevated rates of mental health disorders when compared to the general population. This study investigated risk factors for mental health disorders relating to the period prior to entering care and while in care. A representative sample of 43 children in care aged 0-72 months in an inner London borough underwent comprehensive multidimensional assessments. Presence of emotional, behavioural, attachment and adaptive disorders was ascertained. Exposure to two pre-placement risk factors and six placement risk factors was compared between children with and without a disorder. A total of 26 children (60.5%) had at least one mental health disorder. The two pre-placement risk factors, multiple types of maltreatment and entry into care after the age of 6 months, were both significantly associated with mental health disorders. The three placement risk factors of sudden placement moves, multiple placement moves and child-carer alienation showed a significant association with mental health disorders. There was a strong correlation between the number of risk factors and the number of co-morbid mental health disorders per child (r = .67, p school mental health. © The Author(s) 2014.

Endoskopisk ultralydvejledt rendezvous til intern drænage ved galdevejsobstruktion

DEFF Research Database (Denmark)

Knudsen, Marie Høxbro; Vilmann, Peter; Hassan, Hazem

2015-01-01

Endoscopic ultrasound guided rendezvous for biliary drainage Endoscopic retrograde cholangiography (ERCP) is currently standard treatment for biliary drainage. Endoscopic ultrasound guided rendezvous (EUS-RV) is a novel method to overcome an unsuccessful biliary drainage procedure. Under endoscopic...

In-bore setup and software for 3T MRI-guided transperineal prostate biopsy

International Nuclear Information System (INIS)

Tokuda, Junichi; Tuncali, Kemal; Song, Sang-Eun; Fedorov, Andriy; Oguro, Sota; Fennessy, Fiona M; Tempany, Clare M; Hata, Nobuhiko; Iordachita, Iulian; Lasso, Andras

2012-01-01

MRI-guided prostate biopsy in conventional closed-bore scanners requires transferring the patient outside the bore during needle insertion due to the constrained in-bore space, causing a safety hazard and limiting image feedback. To address this issue, we present our custom-made in-bore setup and software to support MRI-guided transperineal prostate biopsy in a wide-bore 3 T MRI scanner. The setup consists of a specially designed tabletop and a needle-guiding template with a Z-frame that gives a physician access to the perineum of the patient at the imaging position and allows the physician to perform MRI-guided transperineal biopsy without moving the patient out of the scanner. The software and Z-frame allow registration of the template, target planning and biopsy guidance. Initially, we performed phantom experiments to assess the accuracy of template registration and needle placement in a controlled environment. Subsequently, we embarked on our clinical trial (N = 10). The phantom experiments showed that the translational errors of the template registration along the right–left (RP) and anterior–posterior (AP) axes were 1.1 ± 0.8 and 1.4 ± 1.1 mm, respectively, while the rotational errors around the RL, AP and superior–inferior axes were (0.8 ± 1.0)°, (1.7 ± 1.6)° and (0.0 ± 0.0)°, respectively. The 2D root-mean-square (RMS) needle-placement error was 3 mm. The clinical biopsy procedures were safely carried out in all ten clinical cases with a needle-placement error of 5.4 mm (2D RMS). In conclusion, transperineal prostate biopsy in a wide-bore 3T scanner is feasible using our custom-made tabletop setup and software, which supports manual needle placement without moving the patient out of the magnet. (paper)

Sediment Placement Areas 2012

Data.gov (United States)

California Natural Resource Agency — Dredge material placement sites (DMPS), including active, inactive, proposed and historical placement sites. Dataset covers US Army Corps of Engineers San Francisco...

Sediment Placement Areas 2012

Data.gov (United States)

California Department of Resources — Dredge material placement sites (DMPS), including active, inactive, proposed and historical placement sites. Dataset covers US Army Corps of Engineers San Francisco...

Measurement of the Inclusive and Fiducial Cross-Section of Single Top-Quark $t$-Channel Events in $pp$ Collisions at $\\sqrt{s}$ = 8 TeV

CERN Document Server

The ATLAS collaboration

2014-01-01

This note presents the measurement of a $t$-channel single top-quark production fiducial cross-section in the lepton+jets channel with 20.3 fb$^{-1}$ of 8 TeV data using a neural-network discriminant. Events are selected by requiring exactly two jets, where one of the jets is required to be $b$-tagged. Signal events from $t$-channel single top-quark processes are enhanced using a neural-network discriminant based on final-state observables. The $t$-channel production cross-section in the fiducial region is obtained from a binned maximum-likelihood fit to the neural-network discriminant. A fiducial cross-section quoted within the detector acceptance of $\\sigma_{\\rm fid} = 3.37 \\pm 0.05 \\, (\\mathrm{stat.}) \\pm 0.47 \\, (\\mathrm{syst.}) \\pm 0.09 \\, (\\mathrm{lumi.})~\\text{pb}$ is obtained. The total inclusive $t$-channel cross-section is calculated using the acceptance predicted by various Monte Carlo generators. If the acceptance from the aMC@NLO+Herwig event generator is used, a value of $\\sigma_t = 82.6 \\pm 1.2...

Measurements of fiducial and differential cross sections for Higgs boson production in the diphoton decay channel at $\\sqrt{s}=8$ TeV with ATLAS