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Sample records for arteriovenous shunt surgical

  1. Noncavernous arteriovenous shunts mimicking carotid cavernous fistulae

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    Kobkitsuksakul, Chai; Jiarakongmun, Pakorn; Chanthanaphak, Ekachat; Singhara Na Ayudya, Sirintara (Pongpech)

    2016-01-01

    PURPOSE The classic symptoms and signs of carotid cavernous sinus fistula or cavernous sinus dural arteriovenous fistula (AVF) consist of eye redness, exophthalmos, and gaze abnormality. The angiography findings typically consist of arteriovenous shunt at cavernous sinus with ophthalmic venous drainage with or without cortical venous reflux. In rare circumstances, the shunts are localized outside the cavernous sinus, but mimic symptoms and radiography of the cavernous shunt. We would like to present the other locations of the arteriovenous shunt, which mimic the clinical presentation of carotid cavernous fistulae, and analyze venous drainages. METHODS We retrospectively examined the records of 350 patients who were given provisional diagnoses of carotid cavernous sinus fistulae or cavernous sinus dural AVF in the division of Interventional Neuroradiology, Ramathibodi Hospital, Bangkok between 2008 and 2014. Any patient with cavernous arteriovenous shunt was excluded. RESULTS Of those 350 patients, 10 patients (2.85%) were identified as having noncavernous sinus AVF. The angiographic diagnoses consisted of three anterior condylar (hypoglossal) dural AVF, two traumatic middle meningeal AVF, one lesser sphenoid wing dural AVF, one vertebro-vertebral fistula (VVF), one intraorbital AVF, one direct dural artery to cortical vein dural AVF, and one transverse-sigmoid dural AVF. Six cases (60%) were found to have venous efferent obstruction. CONCLUSION Arteriovenous shunts mimicking the cavernous AVF are rare, with a prevalence of only 2.85% in this series. The clinical presentation mainly depends on venous outflow. The venous outlet of the arteriovenous shunts is influenced by venous afferent-efferent patterns according to the venous anatomy of the central nervous system and the skull base, as well as by architectural disturbance, specifically, obstruction of the venous outflow. PMID:27767958

  2. Value of digital subtraction angiography for the evaluation of peripheral arteriovenous shunts in patients with haemodialysis

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    Beil, D.; Bolsinger, G.; Deininger, H.K.

    1987-02-01

    Direct and indirect examination of arteriovenous shunts was performed in 50 patients undergoing haemodialysis. The various methods of puncture of the vessels, the indications and the limitations of DSA are considered. The advantages of direct puncture of the arteriovenous shunt are emphasised. Puncture of the venous branch is almost without risk and allows immediate diagnosis. Only in a very few cases it will be necessary to perform the risky puncture of the arterial branch or the time-consuming central venous injection of a bolus of the contrast medium.

  3. Utility of susceptibility-weighted imaging and arterial spin perfusion imaging in pediatric brain arteriovenous shunting

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    Nabavizadeh, Seyed Ali; Edgar, J.C.; Vossough, Arastoo [University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States); Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States)

    2014-10-15

    The objectives of the study are to investigate the application of susceptibility-weighted imaging (SWI) and arterial spin labeling (ASL) imaging in the assessment of shunting and the draining veins in pediatric patients with arteriovenous shunting and compare the utility of SWI and ASL with conventional MR and digital subtraction angiography (DSA). This study is a retrospective study of 19 pediatric patients with arteriovenous shunting on brain MRI who were also evaluated with DSA. We assessed the ability of conventional MRI sequences, susceptibility magnitude images, phase-filtered SWI images, and pulsed ASL images in the detection of arteriovenous (AV) shunting, number of draining veins and drainage pathways in comparison to DSA. The mean number of detected draining veins on DSA (3.63) was significantly higher compared to SWI phase-filtered image (mean = 2.72), susceptibility magnitude image (mean = 2.92), ASL (mean = 1.76) and conventional MRI (2.47) (p < 0.05). Pairwise comparison of DSA difference scores (i.e., difference between MR modalities in the number of missed draining veins) revealed no difference between the MR modalities (p > 0.05). ASL was the only method that correctly identified superficial and deep venous drainage in all patients. Regarding detection of shunting, ASL, SWI phase-filtered, and magnitude images demonstrated shunting in 100, 83, and 84 % of patients, respectively. SWI depicts a higher number of draining vein compared to conventional MR pulse sequences. ASL is a sensitive approach in showing 100 % sensitivity in the detection of AV shunting and in the diagnosis of the pattern of venous drainage. The present findings suggest the added utility of both SWI and ASL in the assessment of AV shunting. (orig.)

  4. Evaluation of the degree of arteriovenous shunting in intracranial arteriovenous malformations using pseudo-continuous arterial spin labeling magnetic resonance imaging

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    Sunwoo, Leonard; Park, Sun-Won [Seoul Metropolitan Government - Seoul National University Boramae Medical Center, Department of Radiology, Seoul (Korea, Republic of); Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Sohn, Chul-Ho; Yun, Tae Jin; Choi, Seung Hong; Cho, Young Dae; Kim, Ji-hoon; Han, Moon Hee [Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); Lee, Jong Young [Kangdong Sacred Heart Hospital, Department of Neurosurgery, Seoul (Korea, Republic of); Yi, Kyung Sik [Chungbuk National University Hospital, Department of Radiology, Cheongju (Korea, Republic of); Paek, Sun Ha; Kim, Yong Hwy; Kim, Jin Wook; Chung, Hyun-Tai; Kim, Dong Gyu [Seoul National University Hospital, Department of Neurosurgery, Seoul (Korea, Republic of)

    2015-08-15

    Intracranial arteriovenous malformations (AVMs) display venous signals on arterial spin labeling (ASL) magnetic resonance (MR) imaging due to the presence of arteriovenous shunting. Our aim was to quantitatively correlate AVM signal intensity on ASL with the degree of arteriovenous shunting estimated on digital subtraction angiography (DSA) in AVMs. MR imaging including pseudo-continuous ASL at 3 T and DSA were obtained on the same day in 40 patients with intracranial AVMs. Two reviewers assessed the nidus and venous signal intensities on ASL images to determine the presence of arteriovenous shunting. Interobserver agreement on ASL between the reviewers was determined. ASL signal intensity of the AVM lesion was correlated with AVM size and the time difference between normal and AVM venous transit times measured from the DSA images. Interobserver agreement between two reviewers for nidus and venous signal intensities was excellent (κ = 0.80 and 1.0, respectively). Interobserver agreement regarding the presence of arteriovenous shunting was perfect (κ = 1.0). AVM signal intensity showed a positive relationship with the time difference between normal and AVM venous transit times (r = 0.638, P < 0.001). AVM signal intensity also demonstrated a positive relationship with AVM size (r = 0.561, P < 0.001). AVM signal intensity on ASL in patients with AVM correlates well with the degree of early vein opacification on DSA, which corresponds to the degree of arteriovenous shunting. (orig.)

  5. Creation of an iliac arteriovenous shunt lowers blood pressure in chronic obstructive pulmonary disease patients with hypertension.

    LENUS (Irish Health Repository)

    Faul, John

    2014-01-28

    Vasodilators are used with caution in patients with chronic obstructive pulmonary disease (COPD). We have developed a device for percutaneous arteriovenous shunt creation in the iliac region to increase cardiac output and oxygen delivery for patients with COPD. Although this device does not cause significant blood pressure changes in normotensive patients with COPD, we hypothesized that arteriovenous shunt creation might cause vasodilator effects in hypertensive patients because of a reduction in vascular resistance.

  6. Arteriovenous shunt graft ulceration with sinus and graft epithelialization

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    Pooja Singhal

    2015-03-01

    Full Text Available Arteriovenous fistula and grafts are used as access sites for patients with chronic kidney disease and are prone for complications. Stent grafts are used to treat access site complications. We report a rare and unusual finding of epithelialization of the sinus tract and the lumen of a polytetrafluoroethylene graft, following ulceration of the overlying skin.

  7. Cranial dural arteriovenous shunts. Part 1. Anatomy and embryology of the bridging and emissary veins.

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    Baltsavias, Gerasimos; Parthasarathi, Venkatraman; Aydin, Emre; Al Schameri, Rahman A; Roth, Peter; Valavanis, Anton

    2015-04-01

    We reviewed the anatomy and embryology of the bridging and emissary veins aiming to elucidate aspects related to the cranial dural arteriovenous fistulae. Data from relevant articles on the anatomy and embryology of the bridging and emissary veins were identified using one electronic database, supplemented by data from selected reference texts. Persisting fetal pial-arachnoidal veins correspond to the adult bridging veins. Relevant embryologic descriptions are based on the classic scheme of five divisions of the brain (telencephalon, diencephalon, mesencephalon, metencephalon, myelencephalon). Variation in their exact position and the number of bridging veins is the rule and certain locations, particularly that of the anterior cranial fossa and lower posterior cranial fossa are often neglected in prior descriptions. The distal segment of a bridging vein is part of the dural system and can be primarily involved in cranial dural arteriovenous lesions by constituting the actual site of the shunt. The veins in the lamina cribriformis exhibit a bridging-emissary vein pattern similar to the spinal configuration. The emissary veins connect the dural venous system with the extracranial venous system and are often involved in dural arteriovenous lesions. Cranial dural shunts may develop in three distinct areas of the cranial venous system: the dural sinuses and their interfaces with bridging veins and emissary veins. The exact site of the lesion may dictate the arterial feeders and original venous drainage pattern.

  8. Fistulectomy as a surgical option for pulmonary arteriovenous malformation

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shao-yan; ZHANG Zhi-tai; OU Song-lei; HU Yan-sheng; SONG Fei-qiang; LI Xin; MA Xu-chen; MA Xin-xin; LIANG Lin; LI Dong; GUO Lin; SUN Zhen

    2009-01-01

    Background Surgical resection remains the treatment of choice for pulmonary arteriovenous malformation but removes some normal lung parenchyma. This study aimed to evaluate the effect and safety of the lung-saving procedure of fistulectomy as an alternative to lung resection.Methods From July 2003 to July 2008, 6 selected patients with pulmonary arteriovenous malformations underwent fistulectomies. Among them, 1 patient underwent emergency operation and 2 underwent bilateral operations. One patient received postoperative embolotherapy.Results No hospital deaths or postoperative morbidity occurred. PaO_2 increased significantly after operation. All patients were free of symptoms and hypoxia during a follow-up for 9 months to 5 years.Conclusions Fistulectomy is a safe and effective procedure for patients with pulmonary arteriovenous malformation and may be an alternative to lung resection.

  9. Surgical Management of Combined Intramedullary Arteriovenous Malformation and Perimedullary Arteriovenous Fistula within the Hybrid Operating Room after Five Years of Performing Focus Fractionated Radiotherapy: Case Report

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    GEKKA, Masayuki; SEKI, Toshitaka; HIDA, Kazutoshi; OSANAI, Toshiya; HOUKIN, Kiyohiro

    2014-01-01

    Perimedullary arteriovenous fistula (AVF) shunts occur on the spinal cord surface and can be treated surgically or by endovascular embolization. In contrast, the nidus of an intramedullary arteriovenous malformation (AVM) is located in the spinal cord and is difficult to treat surgically or by endovascular techniques. The benefits of radiotherapy for treating intramedullary AVM have been published, but are anecdotal and consist largely of case reports. We present a case of combined cervical intramedullary AVM and perimedullary AVF which received surgical treatment within a hybrid operating room (OR) after 5 years of focus fractionated radiotherapy. A 37-year-old male presented with stepwise worsening myelopathy. Magnetic resonance imaging and spinal angiography revealed intramedullary AVM and perimedullary AVF at the C3 to C5 levels. In order to reduce nidus size and blood flow, we first performed focal fractionated radiotherapy. Five years later, the lesion volume was reduced. Following this, direct surgery was performed by an anterior approach using corpectomy in the hybrid OR. The spinal cord was monitored by motor-evoked potential throughout the surgery. Complete obliteration of the fistulous connection was confirmed by intraoperative indocyanine green video-angiography and intraoperative angiography, preserving the anterior spinal artery. We conclude that surgical treatment following focal fractionated radiotherapy may become one strategy for patients who are initially deemed ineligible for endovascular embolization and surgical treatment. Furthermore, the hybrid OR enables safe and precise treatment for spinal vascular disorders in the fields of endovascular treatment and neurosurgery. PMID:25367581

  10. Surgical management of combined intramedullary arteriovenous malformation and perimedullary arteriovenous fistula within the hybrid operating room after five years of performing focus fractionated radiotherapy: case report.

    Science.gov (United States)

    Gekka, Masayuki; Seki, Toshitaka; Hida, Kazutoshi; Osanai, Toshiya; Houkin, Kiyohiro

    2014-01-01

    Perimedullary arteriovenous fistula (AVF) shunts occur on the spinal cord surface and can be treated surgically or by endovascular embolization. In contrast, the nidus of an intramedullary arteriovenous malformation (AVM) is located in the spinal cord and is difficult to treat surgically or by endovascular techniques. The benefits of radiotherapy for treating intramedullary AVM have been published, but are anecdotal and consist largely of case reports. We present a case of combined cervical intramedullary AVM and perimedullary AVF which received surgical treatment within a hybrid operating room (OR) after 5 years of focus fractionated radiotherapy. A 37-year-old male presented with stepwise worsening myelopathy. Magnetic resonance imaging and spinal angiography revealed intramedullary AVM and perimedullary AVF at the C3 to C5 levels. In order to reduce nidus size and blood flow, we first performed focal fractionated radiotherapy. Five years later, the lesion volume was reduced. Following this, direct surgery was performed by an anterior approach using corpectomy in the hybrid OR. The spinal cord was monitored by motor-evoked potential throughout the surgery. Complete obliteration of the fistulous connection was confirmed by intraoperative indocyanine green video-angiography and intraoperative angiography, preserving the anterior spinal artery. We conclude that surgical treatment following focal fractionated radiotherapy may become one strategy for patients who are initially deemed ineligible for endovascular embolization and surgical treatment. Furthermore, the hybrid OR enables safe and precise treatment for spinal vascular disorders in the fields of endovascular treatment and neurosurgery.

  11. Surgical management of multiple posttraumatic arteriovenous fistulas of femoral vessels.

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    Pokrovsky, A V; Shubin, A A; Kuntsevich, G I; Subbotin, V V; Suntsov, D S

    2008-01-01

    Presented herein are two case reports concerning surgical management of posttraumatic arteriovenous fistulas of femoral vessels. Case 1. A 45-year-old female patient attended with a history of a shotgun injury wound of her left femur and crus sustained when a girl of eight. She sought medical attention for a progressively deteriorating condition, accompanied by pain, and breathlessness dyspnea at rest. Detected were multiple fistulas between the deep femoral artery and superficial femoral artery and femoral vein. Management consisted in separation of the arteriovenous fistulas, followed by prosthetic repair of the deep femoral artery. Case 2. A 32-year-old male patient after an accidentally inflicted shotgun injury of the his left femur underwent within a time period of 3 year three vascular operations including ligation of the deep femoral artery and femoral vein followed by having later on developed secondary lymphedema of his left lower limb and pronounced manifested chronic venous insufficiency. Management included dissociation of the numerous arteriovenous fistulas between the branches of the deep femoral artery and the common femoral artery, as well as between the superficial femoral artery and femoral vein.

  12. Surgical treatment of idiopathic syringomyelia: Silastic wedge syringosubarachnoid shunting technique

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    Teck M Soo

    2014-01-01

    Conclusions: Shunting procedures for the syringomyelia disease spectrum have been criticized due to the inconsistent long-term outcomes. This surgical technique used to treat symptomatic idiopathic syringomyelia has been devised based on our intraoperative experience, surgical outcomes, and evaluation of the literature. The purpose of the wedges is to preserve patency of the communication between the syrinx cavity and the expanded subarachnoid space by preventing healing of the myelotomy edges and by maintaining an artificial conduit between the syrinx cavity and the subarachnoid space. Although short-term results are promising, continued long-term follow up is needed to determine the ultimate success of the silastic wedge shunting procedure.

  13. Surgical treatment of complicated traumatic aneurysm and arteriovenous fistula

    Institute of Scientific and Technical Information of China (English)

    乔正荣; 时德

    2003-01-01

    Objective: To evaluate the surgical methods and the outcome of management for traumatic arterial aneurysm (TAA) and traumatic arteriovenous fistula (TAVF). Methods: A total of 121 patients with TAA or TAVF were treated by surgery. Clinical, operative and postoperative data were collected and analyzed retrospectively. Results: The surgical techniques included aneurysmectomy and arterial end-to-end anastomosis or vascular grafting or artery ligation, aneurysm ligation and bypass, vascular repair, fistula excision and vascular ligation or vascular grafting or repair and so on. One patient died (0.83%). The follow-up rates of TAA and TAVF were 65.7% and 60% respectively. Conclusions: Complicated TAA and TAVF in different sites should be treated with different methods.

  14. Endovascular and surgical treatment of spinal dural arteriovenous fistulas

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    Andres, Robert H. [University of Berne (Switzerland). Department of Neurosurgery; University of Berne (Switzerland). Department of Diagnostic and Interventional Neuroradiology; Stanford University Medical Center, Department of Neurosurgery, Stanford, CA (United States); University of Berne (Switzerland). Inselspital; Barth, Alain [University of Berne (Switzerland). Department of Neurosurgery; Medical University of Graz, Department of Neurosurgery, Graz (Austria); University of Berne (Switzerland). Inselspital; Guzman, Raphael [University of Berne (Switzerland). Department of Neurosurgery; Stanford University Medical Center, Department of Neurosurgery, Stanford, CA (United States); University of Berne (Switzerland). Inselspital; Remonda, Luca; El-Koussy, Marwan; Schroth, Gerhard [University of Berne (Switzerland). Department of Diagnostic and Interventional Neuroradiology; University of Berne (Switzerland). Inselspital; Seiler, Rolf W.; Widmer, Hans R. [University of Berne (Switzerland). Department of Neurosurgery; University of Berne (Switzerland). Inselspital

    2008-10-15

    The aim of this retrospective study was to evaluate the clinical outcome of patients with spinal dural arteriovenous fistulas (SDAVFs) that were treated with surgery, catheter embolization, or surgery after incomplete embolization. The study included 21 consecutive patients with SDAVFs of the thoracic, lumbar, or sacral spine who were treated in our institution from 1994 to 2007. Thirteen patients were treated with catheter embolization alone. Four patients underwent hemilaminectomy and intradural interruption of the fistula. Four patients were treated by endovascular techniques followed by surgery. The clinical outcome was assessed using the modified Aminoff-Logue scale (ALS) for myelopathy and the modified Rankin scale (MRS) for general quality of life. Patient age ranged from 44 to 77 years (mean 64.7 years). Surgical as well as endovascular treatment resulted in a significant improvement in ALS (-62.5% and -31.4%, respectively, p<0.05) and a tendency toward improved MRS (-50% and -32%, respectively) scores. Patients that underwent surgery after endovascular treatment due to incomplete occlusion of the fistula showed only a tendency for improvement in the ALS score (-16.7%), whereas the MRS score was not affected. We conclude that both endovascular and surgical treatment of SDAVFs resulted in a good and lasting clinical outcome in the majority of cases. In specific situations, when a secondary neurosurgical approach was required after endovascular treatment to achieve complete occlusion of the SDAVF, the clinical outcome was rather poor. The best first line treatment modality for each individual patient should be determined by an interdisciplinary team. (orig.)

  15. Assessment of surgical portosystemic shunts and associated complications: The diagnostic and therapeutic role of radiologists

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    Taslakian, Bedros, E-mail: btaslakian@gmail.com [Department of Radiology, American University of Beirut Medical Center, Riad El-Solh 1107 2020—PO Box: 11-0236, Beirut (Lebanon); Faraj, Walid, E-mail: wf07@aub.edu.lb [Department of General Surgery, American University of Beirut Medical Center, Riad El-Solh 1107 2020—PO Box: 11-0236, Beirut (Lebanon); Khalife, Mohammad, E-mail: mk12@aub.edu.lb [Department of General Surgery, American University of Beirut Medical Center, Riad El-Solh 1107 2020—PO Box: 11-0236, Beirut (Lebanon); Al-Kutoubi, Aghiad, E-mail: mk00@aub.edu.lb [Department of Radiology, American University of Beirut Medical Center, Riad El-Solh 1107 2020—PO Box: 11-0236, Beirut (Lebanon); El-Merhi, Fadi, E-mail: fe19@aub.edu.lb [Department of Radiology, American University of Beirut Medical Center, Riad El-Solh 1107 2020—PO Box: 11-0236, Beirut (Lebanon); Saade, Charbel, E-mail: cs39@aub.edu.lb [Department of Radiology, American University of Beirut Medical Center, Riad El-Solh 1107 2020—PO Box: 11-0236, Beirut (Lebanon); Hallal, Ali, E-mail: ah05@aub.edu.lb [Department of General Surgery, American University of Beirut Medical Center, Riad El-Solh 1107 2020—PO Box: 11-0236, Beirut (Lebanon); Haydar, Ali, E-mail: ah24@aub.edu.lb [Department of Radiology, American University of Beirut Medical Center, Riad El-Solh 1107 2020—PO Box: 11-0236, Beirut (Lebanon)

    2015-08-15

    Highlights: • Portal hypertension is the pathological increase in portal venous pressure. • Surgical portosystemic shunting is an accepted methods to decrease portal venous pressure. • Surgical portosystemic shunts are divided into selective and nonselective. • Shunt thrombosis is a serious complication, resulting in shunt dysfunction. • Imaging is essential in the assessment of the shunt function and anatomy. - Abstract: Surgical portosystemic shunting, the formation of a vascular connection between the portal and systemic venous circulation, has been used as a treatment to reduce portal venous pressure. Although the use of portosystemic shunt surgery in the management of portal hypertension has declined during the past decade in favour of alternative therapies, and subsequently surgeons and radiologists became less familiar with the procedure, it remains a well-established treatment. Knowledge of different types of surgical portosystemic shunts, their pathophysiology and complications will help radiologists improve communication with surgeons and enhance their understanding of the diagnostic and therapeutic role of radiology in the assessment and management of these shunts. Optimal assessment of the shunt is essential to determine its patency and allow timely intervention. Both non-invasive and invasive imaging modalities complement each other in the evaluation of surgical portosystemic shunts. Interventional radiology plays an important role in the management of complications, such as shunt thrombosis and stenosis. This article describes the various types of surgical portosystemic shunts, explains the anatomy and pathophysiology of these shunts, illustrates the pearls and pitfalls of different imaging modalities in the assessment of these shunts and demonstrates the role of radiologists in the interventional management of complications.

  16. Assessment of surgical portosystemic shunts and associated complications: The diagnostic and therapeutic role of radiologists.

    Science.gov (United States)

    Taslakian, Bedros; Faraj, Walid; Khalife, Mohammad; Al-Kutoubi, Aghiad; El-Merhi, Fadi; Saade, Charbel; Hallal, Ali; Haydar, Ali

    2015-08-01

    Surgical portosystemic shunting, the formation of a vascular connection between the portal and systemic venous circulation, has been used as a treatment to reduce portal venous pressure. Although the use of portosystemic shunt surgery in the management of portal hypertension has declined during the past decade in favour of alternative therapies, and subsequently surgeons and radiologists became less familiar with the procedure, it remains a well-established treatment. Knowledge of different types of surgical portosystemic shunts, their pathophysiology and complications will help radiologists improve communication with surgeons and enhance their understanding of the diagnostic and therapeutic role of radiology in the assessment and management of these shunts. Optimal assessment of the shunt is essential to determine its patency and allow timely intervention. Both non-invasive and invasive imaging modalities complement each other in the evaluation of surgical portosystemic shunts. Interventional radiology plays an important role in the management of complications, such as shunt thrombosis and stenosis. This article describes the various types of surgical portosystemic shunts, explains the anatomy and pathophysiology of these shunts, illustrates the pearls and pitfalls of different imaging modalities in the assessment of these shunts and demonstrates the role of radiologists in the interventional management of complications.

  17. Percutaneous arteriovenous shunting in patients with severe COPD. A new interventional radiological treatment; Perkutane arteriovenoese Shuntanlage bei Patienten mit schwerer COPD. Eine neue interventionelle radiologische Technik

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    Schlosser, Thomas; Forsting, M. [Universitaetsklinikum Essen (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie und Neuroradiologie; Burbelko, M. [Marburg Univ. (Germany). Klinik fuer Strahlendiagnostik; Ulrich, M. [Parkkrankenhaus Leipzig (Germany). Klinik fuer Innere Medizin/Angiologie/Kardiologie; Ludwig, F.; Reutiman, T. [ROX Medical, San Clemente, CA (United States); Antoch, G. [Universitaetsklinikum Duesseldorf (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie; Adamus, R. [Klinikum Nuernberg Nord (Germany). Inst. fuer Radiologie

    2013-03-15

    Purpose: The aim of this study was to evaluate the technical feasibility and safety of a new interventional radiological technique to create a shunt percutanously between the external iliac vein and artery in patients with severe COPD. Materials and Methods: 40 patients were included in this multicenter trial. In 38 patients the artery was punctured from the vein using a novel crossing needle. A special delivery system was used to implant a novel nitinol device (ACS, ROX Medical) between the artery and the vein to maintain a 4 mm calibrated and structured fistula between the two vessels. Results: Shunt implantation was successful in 38 patients. The perfused arteriovenous shunts could be well documented in DSA and the diameter was measured between 3 and 4 mm in all cases. Peri-interventional non-flow-limiting dissection of the iliac artery occurred in one patient. Post-interventional venous bleeding in two patients was treated successfully by local compression. In one patient a peripheral artery thrombembolism was successfully treated by thrombolysis. Conclusion: The new interventional radiological technique to create an arteriovenous shunt in the iliac vessels presented in this study has proven to be feasible and safe. (orig.)

  18. Antithrombotic activity of F 16618, a new PAR1 antagonist evaluated in extracorporeal arterio-venous shunt in the rat.

    Science.gov (United States)

    Létienne, Robert; Leparq-Panissié, Anne; Calmettes, Yannick; Nadal-Wollbold, Florence; Perez, Michel; Le Grand, Bruno

    2010-06-01

    The purpose of the present work was the evaluation of the antithrombotic activity of a new PAR1 antagonist, F 16618 in arterio-venous shunt in the rat. Arterial thrombosis was induced by insertion of a silk thread (thrombogenic substrate) into an extracorporeal shunt. F 16618 was administered either by intravenous route (0.63-2.5mg/kg) or by oral route (20-80mg/kg). Oral activity of F 16618 was compared to that of aspirin (20-80mg/kg) and clopidogrel (0.63-10mg/kg). Finally, F 16618 was associated to aspirin and/or clopidogrel to test for possible antithrombotic activity and its effects on bleeding time. SFLLR-induced human platelet aggregation was evaluated in the presence of F 16618, demonstrating the anti-aggregant activity of this compound. F 16618 (1.25mg/kg) significantly delayed the time leading to occlusion by 52+/-17%, without affecting bleeding time and in absence of hemodynamic effects. F 16618 given orally dose-dependently increased the time to occlusion. The maximal effect was observed at 40mg/kg (984+/-95s versus 644+/-17s in vehicle group). Aspirin and clopidogrel also dose-dependently lengthened time to occlusion, but this effect was associated with an increase of bleeding time. F 16618 (20mg/kg) orally associated with either aspirin (40mg/kg) or with clopidogrel (1.25mg/kg) potentiated the antithrombotic effects of both compounds without further increasing of bleeding time. In conclusion, F 16618 exerted a potent antithrombotic activity by intravenous and oral routes, without affecting bleeding time. Furthermore, the antithrombotic activity was potentiated when combined with aspirin or clopidogrel.

  19. Surgical management of a pial arteriovenous fistula with giant varix in an infant

    Directory of Open Access Journals (Sweden)

    Pillai Ashok

    2006-01-01

    Full Text Available A seven-month-old infant presented with a generalized seizure. The radiological evaluation revealed a large arteriovenous fistula in the left sylvian region. The fistula connected the left middle cerebral artery and the vein of Trolard. A giant varix was present at the venous end. The child underwent craniotomy, complete disconnection of the fistula and excision of the varix. Except for recurrent seizures, which were eventually controlled on anticonvulsants, the child′s neurological development has been good on long-term follow-up of three years. Pial arteriovenous fistulae are rare intracranial vascular malformations. Though significant operative risks exist, they can be successfully managed surgically with good long-term prognosis.

  20. Surgical strategy for cerebral arteriovenous malformation with acute hemorrhage

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    BACKGROUND: Presently, there have been craniocerebral operation, interventional embolization,stereotactic radiotherapy and other methods in treating cerebral arteriovenous malformation (AVM).However, the standard of different therapeutic regimens of cerebral AVM at the acute stage of hemorrhage has not been completely identified.OBJECTIVE: To observe the clinical characteristics and therapeutic effects of AVM at the acute stage of hemorrhage in patients, and to analyze corresponding therapeutic strategies.DESIGN: Non-randomized clinical observation.SETTING: Department of Neurosurgery, Foshan First People's Hospital, Sun Yat-sen University.PARTICIPANTS: Forty-six patients with cerebral AVM complicated by hemorrhage admitted to Department of Neurosurgery, Foshan First People's Hospital between January 1999 and December 2006,were involved in this study. All the patients were confirmed as cerebral AVM complicated by hemorrhage by brain angiography or/and postoperational pathology. The involved patients, 32 males and 14 females,averaged 25 years old, ranging from 6 to 62 years. Informed consents of therapeutic items were obtained from the relatives of all the patients.METHODS: ①On admission, skull CT and brain angiography were conducted in the involved subjects. ②The therapeutic method was confirmed according to the consciousness, hematoma region, hematoma volume,imageological results following comprehensive analysis: DSA examination was permitted to identify the size and position of abnormal vessel mass, and the distribution of feeding artery and draining vein. Craniocerebral operation was carried out as early as possible in patients with severe or progressive conscious disturbance, in which most of hematoma with obvious occupied effect or cerebral hernia was located in lobe of brain. The primary thing was to clean intracerebral hematoma for in time decompression. According to different situations, corresponding therapeutic measures were used for resecting abnormal

  1. Refashioning of an aneurysmatic arterio-venous fistula by using the multifire GIA 60 surgical stapler.

    Science.gov (United States)

    Hakim, N S; Romagnoli, J; Contis, J C; Akoh, J; Papalois, V E

    1997-01-01

    We describe a technique for refashioning an aneurysmatic arterio-venous fistula by using the multifire GIA 60 surgical stapler. After obtaining proximal and distal control of the aneurysmatic vein each aneurysmal segment of the anterior wall of the vein is excised by applying the GIA 60 stapler. The layer of the staple-line is re-enforced with one layer of 6/0 prolene continuous suture. After completion of the procedure, the size of the vein is reduced by approximately 50%. The AVFs were successfully re-used for dialysis within four weeks postoperatively.

  2. Surgical treatment of hepatocellular carcinoma with severe intratumoral arterioportal shunt

    Institute of Scientific and Technical Information of China (English)

    Hiromichi; Ishii; Teruhisa; Sonoyama; Shingo; Nakashima; Hiroyuki; Nagata; Atsushi; Shiozaki; Yoshiaki; Kuriu; Hisashi; Ikoma; Masayoshi; Nakanishi; Daisuke; Ichikawa; Hitoshi; Fujiwara; Kazuma; Okamoto; Toshiya; Ochiai; Yukihito; Kokuba; Chohei; Sakakura; Eigo; Otsuji

    2010-01-01

    We report a case of hepatocellular carcinoma (HCC) that caused a severe arterioportal shunt (APS). A 49-year-old man was admitted to hospital due to esophagogastric variceal hemorrhage and HCC, and underwent endoscopic variceal ligation (EVL) and endoscopic injection sclerotherapy (EIS). He was then referred to our hospital. Abdominal computed tomography revealed a lowdensity lesion in the posterior segment of the liver and an intratumoral APS, which caused portal hypertension. Although the patient underwen...

  3. [INTERVENTIONAL AND SURGICAL TREATMENT OF THE ANGINA PECTORIS RECURRENCE AFTER CORONARY SHUNTING OPERATION].

    Science.gov (United States)

    Fanta, S M

    2015-12-01

    There were examined 134 patients, in whom in the clinic in 2005-2014 yrs a coronary shunting operation was performed. In patients with the angina pectoris recurrence a reoperation is indicated. The data of repeated coronaroventriculography and shuntography were analyzed. Efficacy of the surgical and interventional methods application in the patients was proved.

  4. Anesthesia considerations and intraoperative monitoring during surgery for arteriovenous malformations and dural arteriovenous fistulas.

    Science.gov (United States)

    Miller, Christina; Mirski, Marek

    2012-01-01

    The anesthetic considerations for surgical resection of arteriovenous malformations (AVMs) and dural arteriovenous fistulas (DAVFs) incorporate many principles that are common to craniotomies for other indications. However, a high-flow, low-resistance shunt results in chronic hypoperfusion of adjacent brain tissue that is vulnerable to ischemia and at high risk for hyperemia and hemorrhage as resection of the lesion redirects blood flow. A comprehensive understanding of AVM pathophysiology and rapidly titratable anesthetic and vasoactive agents allow the anesthesiologist to alter blood pressure targets as resection evolves for optimal patient outcome. Intensive management is continued post-operatively as the brain acclimatizes to new parameters.

  5. A case report of congenital umbilical arteriovenous malformation complicated with liver failure after surgical excision

    Science.gov (United States)

    Han, Ji-Won; Kim, Hyun-Young; Jung, Sung-Eun

    2017-01-01

    Abstract Rationale: Few case reports of umbilical arteriovenous malformation (AVM) have been reported. Herein, we report a neonatal case of umbilical AVM who underwent liver failure after surgical excision. Patient concerns: The patient was a girl delivered at a gestational age of 39+5 weeks showing cyanosis and heart murmur. Diagnoses: Cardiac echography, abdominal ultrasonography (USG), and computed tomography revealed suspecting the umbilical AVM. Interventions: On the eighth day after birth, because of the aggravation of heart failure, emergency surgery for excision of umbilical AVM was performed. Outcomes: In postoperative state, worsened laboratory test of liver function and coagulopathy indicated the liver failure. Abdominal USG revealed that the portal vein (PV) flow primarily occurred from the left PV to the inferior vena cava via ductus venosus and coarse hepatic echogenicity. After conservative management, laboratory findings of liver function and the flow direction of the left PV were normal, as demonstrated by abdominal USG within 50th postoperative day. Lessons: Careful preoperative evaluation of an AVM of a large size with significant blood flow should be performed, and the possibility of liver failure after surgery should always be considered. PMID:28178121

  6. Revisiting the surgical creation of volume load by aorto-caval shunt in rats.

    Science.gov (United States)

    Ocampo, Catherina; Ingram, Paul; Ilbawi, Michel; Arcilla, Rene; Gupta, Madhu

    2003-09-01

    Cardiac hypertrophy is an early landmark during the clinical course of heart failure, and is an important risk factor for subsequent morbidity and mortality. The hypertrophy response to different types of cardiac overload is distinguished both at the molecular and cellular levels. These changes have been extensively characterized for pressure load hypertrophy; however, similar information for volume load hypertrophy is still needed. This study was undertaken to improve the existing method of producing experimental cardiac volume load. Previous investigators have employed surgical aorto-caval shunt (ACS) as a model for volume load hypertrophy (VO) in rats. The procedure is relatively simple and involves glue to seal the aortic hole after ACS. However, it has several limitations mostly related to the use of glue e.g. poor visualization due to hardening of tissues, imperfect sealing of the puncture site and glue seeping through the aortic hole resulting in shunt occlusion. We have modified the procedure using aortic adventitial suture instead of glue and 18G angiocatheter instead of 16G needle, which eliminated the technical difficulties from the former method. The ACS was visually confirmed at sacrifice, and the VO demonstrated by time-related changes in the heart weight/body weight ratio which increased from 78% at 4 weeks to 87% at 10 weeks and increased liver/body weight ratio by 22% at 10 weeks of post aorto-caval shunt. Cardiac expression of atrial natriuretic peptide (ANF) also demonstrated time-related increase in ANF mRNA (+275% increase at 4 weeks, p < 0.05, and +370% increase at 10 weeks, p < 0.001). This modified technique of aorto-caval shunt offers simpler, reproducible and consistent model for VO hypertrophy in rats.

  7. Obstructed surgical porto-systemic shunts in the early postoperative period: interventional therapy by angioplasty (PTA) and stent placement; Obstruktion chirurgischer portosystemischer Shunts in der fruehen postoperativen Phase: interventionelle Behandlung durch Angioplastie und Stentimplantation

    Energy Technology Data Exchange (ETDEWEB)

    Strunk, H.; Textor, J.; Koenig, R.; Wilhelm, K.; Schild, H. [Bonn Univ. (Germany). Radiologische Klinik; Wolff, M. [Bonn Univ. (Germany). Chirurgische Klinik und Poliklinik

    2001-05-01

    Recurrent variceal bleeding in patients treated with surgical porto-systemic shunting is most often due to shunt stenoses or occlusion. Radiological interventional procedures are a possible method of therapy and our experience herein is described in this report. Patients and Methods: from 1997 to 1999 54 patients with recurrent variceal bleeding were treated with a surgical porto-systemic shunt procedure. Of these early shunt occlusion occurred in 5 patients, which was treated with percutaneous transcatheter techniques. Results: in only one patient was PTA alone sufficient to reestablish shunt patency, in four patient stent placement was necessary in addition. In the follow-up period 1 patient died 26 month after intervention with (autopsy-proven) patent shunt, in one patient shunt reocclusion occurred after 11 months and in 3 patients the shunt is still patent. Conclusions: PTA, if necessary in combination with stent placement, is an attractive alternative method of therapy in case of an early surgical porto-systemic shunt occlusion. (orig.) [German] Rezidivblutungen nach chirurgischer portosystemischer Shuntanlage sind meistens durch eine Shuntstenose oder einen Shuntverschluss bedingt. Hier stellen interventionelle Eingriffe einen moeglichen therapeutischen Ansatz dar, ueber den im Folgenden berichtet werden soll. Patienten und Methode: zwischen 1997 und 1999 wurde bei insgesamt 54 Patienten wegen rezidivierender Blutungen ein operativer portosystemischer Shunt angelegt. Von diesen zeigten fuenf Patienten in der unmittelbaren postoperativen Periode einen Shuntverschluss, der radiologisch interventionell therapiert wurde. Ergebnisse: bei einem der fuenf Patienten genuegte zur Wiederherstellung des Flusses eine alleinige Ballondilatation (PTA), bei vier Patienten musste zusaetzlich eine Stentimplantation durchgefuehrt werden. In der weiteren Nachsorge ist ein Pat. nach 26 Wochen mit autoptisch offenem Shunt verstorben, bei 3 Pat. ist der Shunt offen, bei einem

  8. Unsatisfactory outcomes of prolonged ischemic priapism without early surgical shunts: our clinical experience and a review of the literature

    Institute of Scientific and Technical Information of China (English)

    Da-Chao Zheng; Hai-Jun Yao; Ke Zhang; Ming-Xi Xu; Qi Chen; Yan-Bo Chen; Zhi-Kang Cai; Mu-Jun Lu; Zhong Wang

    2013-01-01

    Ischemic priapism is a rare occurrence which can cause severe erectile dysfunction (ED) without timely treatment.This retrospective study reports our experience in treating prolonged ischemic priapism and proposes our further considerations.In this paper,a total of nine patients with prolonged ischemic priapism underwent one to three types of surgical shunts,including nine Winter shunts,two AI-Ghorab shunts and one Grayhack shunt.During the follow-up visit (after a mean of 21.11 months),all patients' postoperative characters were recorded,except one patient lost for death.Six postoperative patients accepted a 25-mg oral administration of sildenafil citrate.The erectile function of the patients was evaluated by their postoperative 5-item version of International Index of Erectile Function Questionnaire (IIEF-5),which were later compared with their premorbid scores.All patients had complete resolutions,and none relapsed.The resolution rate was 100%.Seven patients were resolved with Winter shunts,one with an Al-Ghorab shunt and one with a Grayhack shunt.The mean hospital stay was 8.22 days.There was only one urethral fistula,and the incidence of postoperative ED was 66.67%.Four patients with more than a 72-h duration of priapism had no response to the long-term phosphodiesterase type 5 (PDE-5) inhibitor treatment.These results suggest that surgical shunts are an efficient approach to make the penis flaccid after prolonged priapism.However,the severe ED caused by prolonged duration is irreversible,and long-term PDE-5 inhibitor treatments are ineffective.Thus,we recommend early penile prosthesis surgeries for these patients.

  9. [Cisto-peritoneal shunt in the surgical treatment of intracranial arachnoid cysts: an analysis of 49 cases].

    Science.gov (United States)

    Gelabert-González, Miguel

    2011-08-01

    Arachnoid cysts are benign space-occupying lesions formed by an arachnoid membrane containing cerebrospinal fluid. Controversy continues regarding the optimal surgical management. There is ongoing debate regarding whether to fenestrate or to perform shunting of the cyst. We present a single-institution experience on surgical treatment of arachnoid cyst using cistoperitoneal shunt. This serie includes 49 children (31 males/18 females) with a diagnosis of intracranial arachnoid cyst and average age of 4-9 years (range 1-16). The predominant symptom was intracranial hypertension in 26 patients (53%). There were 12 complications in 10 patients. We conclude that arachnoid cyst are located predominantly in the temporal fossa. Cisto-peritoneal shunt is a good option in the younger children and have improved clinical symptoms.

  10. [Childhood transverse sinus dural arteriovenous fistula treated with endovascular and direct surgery: a case report].

    Science.gov (United States)

    Niizuma, Kuniyasu; Sakata, Hiroyuki; Koyama, Shinya; Kon, Hiroyuki; Chonan, Masashi; Sasaki, Tatsuya; Nishijima, Michiharu; Ezura, Masayuki; Tominaga, Teiji

    2012-11-01

    Infantile dural arteriovenous fistula is a rare cerebrovascular malformation carrying a poor prognosis with an anatomic cure of only 9%. Endovascular embolization is mainly selected to treat this entity, aiming to obtain normal development of the patients. We present a case of a 20-month-old girl with epilepsy. Digital subtraction angiography revealed a dural arteriovenous fistula involving the right transverse sinus. The arteriovenous fistula was fed by multiple dural branches from the middle meningeal, occipital, meningohypophyseal, and anteroinferior cerebellar arteries. The right transverse sinus was transvenously embolized with platinum coils. Although the shunt flow remained, the patient was liberated from epilepsy. Nine months later, the patient suffered from a recurrence of epilepsy. Digital subtraction angiography demonstrated some increase in shunt flow. Right middle meningeal, occipital, posterior deep temporal, and tentorial arteries were transarterially embolized using N-butyl cyanoacrylate, followed by complete surgical resection of the right transverse sinus. The shunt flow disappeared after surgery, and her epilepsy improved significantly. Our experience suggests that the combination of endovascular and surgical treatment is effective for recurrent infantile dural arteriovenous fistula.

  11. Spinal dural arterio-venous fistula: Clinico-radiological profile and outcome following surgical occlusion in an Indian neurosurgical center

    Directory of Open Access Journals (Sweden)

    Sivashanmugam Dhandapani

    2013-01-01

    Full Text Available Background: Spinal dural arteriovenous fistula (SDAVF is a common type of spinal vascular lesion. However, there has not been any published study on its clinico-radiological characteristics or surgical outcome from India. Aim: The aim of this study was to determine the clinico-radiological features of patients with SDAVF, outcomes following surgical ligation of the fistula and the various factors involved. Materials and Methods: Patients who were operated for SDAVF were studied for demographic details, symptoms, clinical severity, radiological features and neurological outcome in the form of improvement in gait disability grades. Appropriate statistical tests were performed. Results: There were 22 (19 males, 3 females patients of SDAVF who underwent surgical ligation with a mean age of 55 years. The mean duration of symptoms at presentation was 15 months. Three patients had acute onset while the rest had insidious onset of symptoms. Out of the 22 patients, 11 (50% had motor weakness as the first symptom, 13 (59% were bedridden and 19 (86.4% had bladder involvement at presentation. Thirteen patients had fistulae in thoracic spine, whereas eight had fistulae in the lumbar spine. All had a favorable outcome in the form of at least non-progression of gait disability (14 had improvement while 8 had stabilized. The improvement was non-significantly associated with younger age, acute onset, ambulant status and fistula below T9. It was inversely associated with pain as the first symptom and fluctuant clinical course. Conclusion: Surgical occlusion of SDAVF is usually associated with either improvement or stabilization of motor weakness.

  12. Surgical attenuation of spontaneous congenital portosystemic shunts in dogs resolves hepatic encephalopathy but not hypermanganesemia.

    Science.gov (United States)

    Gow, Adam G; Frowde, Polly E; Elwood, Clive M; Burton, Carolyn A; Powell, Roger M; Tappin, Simon W; Foale, Rob D; Duncan, Andrew; Mellanby, Richard J

    2015-10-01

    Hypermanganesemia is commonly recognized in human patients with hepatic insufficiency and portosystemic shunting. Since manganese is neurotoxic, increases in brain manganese concentrations have been implicated in the development of hepatic encephalopathy although a direct causative role has yet to be demonstrated. Evaluate manganese concentrations in dogs with a naturally occurring congenital shunt before and after attenuation as well as longitudinally following the changes in hepatic encephalopathy grade. Our study demonstrated that attenuation of the shunt resolved encephalopathy, significantly reduced postprandial bile acids, yet a hypermanganasemic state persisted. This study demonstrates that resolution of hepatic encephalopathy can occur without the correction of hypermanganesemia, indicating that increased manganese concentrations alone do not play a causative role in encephalopathy. Our study further demonstrates the value of the canine congenital portosystemic shunt as a naturally occurring spontaneous model of human hepatic encephalopathy.

  13. Usefulness of color and pulsed Doppler's in the evaluation of surgical portosystemic shunts in pediatric patients; Utilidad del Doppler color y pulsado en la valoracion de los shunts portosistemicos quirurgicos en la edad pediatrica

    Energy Technology Data Exchange (ETDEWEB)

    Berrocal, T.; Prieto, C.; Cortes, P.; Rodriguez, R.; Pastor, I. [Hospital Universitario La Paz. Madrid (Spain)

    2003-07-01

    Portosystemic shunts are performed to relieve symptomatic portal hypertension symptomatic or removal pressure in hepatic vascularisation in patients with Budd-Chiari's syndrome. Most surgical portosystemic shunts can be suitably studied by means of ultrasound scan complemented by color and pulsed Dopplers, proved one understands the hemodynamics of the surgical procedures involved. This article demonstrates the usefulness and limitations of the ultrasound scan Duplex Doppler in the evaluation of portosystemic shunts performed on pediatric patients. Pulsed Doppler provides information regarding the nature and direction of blood flow. Color doppler is capable of directly revealing the shunt and, in most cases, permits the anastomosis to be located. The types of shunts that appear include proximal and distal spleno-renal, portocaval and mesocaval. Types of vascular connections are illustrated,s well as expected post-surgical blood flow direction in affected vessels. The ultrasound scanning technique is discussed, as well as the criteria for determining vascular permeability. Also highlighted are the advantages, limitations and diagnostic difficulties associated with the different forms of Doppler. (Author) 17 refs.

  14. High-risk surgical acute renal failure treated by continuous arteriovenous hemodiafiltration: metabolic control and outcome in sixty patients.

    Science.gov (United States)

    van Bommel, E F; Bouvy, N D; So, K L; Vincent, H H; Zietse, R; Bruining, H A; Weimar, W

    1995-01-01

    The outcome and metabolic control was studied in 60 critically ill patients with acute renal failure (ARF) treated by continuous arteriovenous hemodiafiltration (CAVHD) in a single surgical intensive care unit. Mean age (+/- SEM) was 60 +/- 2 years with a male predominance (80%). The majority of patients required mechanical ventilation (83%) and/or vasopressor support (70%) and suffered from multiorgan failure [mean number of organ system failures 3.3 +/- 0.3 (range 1-6)]. CAVHD resulted in a rapid decline of serum urea and creatinine levels during the first 72 h (urea 47.4 +/- 2.3 to 30.3 +/- 1.4 mmol/l, p protein alimentation and often despite hypotension, surgery and septicemia. Significant electrolyte derangements could be easily corrected and maintained within normal limits. Bicarbonate homeostasis could be restored within 48 h in patients with severe metabolic acidosis (HCO3- patients (43%) survived until discharge from the intensive care unit, of whom 23 (38%) survived to leave hospital. Requirement of mechanical ventilation or vasopressor support, higher APACHE II scores and septicemia were all associated with a poor prognosis.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. NG-nitro L-arginine methyl ester: systemic and pulmonary haemodynamics, tissue blood flow and arteriovenous shunting in the pig

    NARCIS (Netherlands)

    E. Marcel van Gelderen (E.); M.O. den Boer (Marinus); P.R. Saxena (Pramod Ranjan)

    1993-01-01

    textabstractThe effects of NG-nitro-Lrarginine methyl ester (L-NAME), an inhibitor of the endothelial nitric oxide (NO) biosynthesis, on systemic and pulmonary haemodynamics, and tissue as well as arteriovenous anastomotic blood flows were investigated in the anaesthetized pig, using simultaneous in

  16. Lumbosubarachnoid-lumboepidural shunting in patients with idiopathic normal-pressure hydrocephalus: surgical procedures and follow-up study of five cases.

    Science.gov (United States)

    Takeuchi, Totaro; Fukushima, Shintaro; Misaki, Daigoro; Shibata, Satoshi

    2013-01-01

    The objective of the study is to introduce the surgical procedure of the lumbosubarachnoid-lumboepidural (L-L) shunting performed as treatment for idiopathic normal-pressure hydrocephalus (iNPH) and its follow-up. The subjects were five patients with probable iNPH (aged 78-85 years; mean age 81 years; four males and one female) who were judged to be at high risk from general or lumbar anesthesia due to their systemic complications and age. The L-L shunt operation was performed for all the patients under local anesthesia using Codman-Hakim Programmable Valve(®) (Codman & Shurtleff, Inc., Raynham, Massachusetts, USA). The initial pressure for all patients was set at 8 cmH2O. The evaluation of shunt efficacy and the lumbar epidural space cerebrospinal fluid (CSF) absorption test (injection of contrast media into epidural space) were performed both on the operation day and during follow-up period (9-12 months). The shunt operation was judged to be effective in four out of five patients (regarded as shunt responders), whereas no improvement in symptoms was seen in one patient (regarded as shunt nonresponder) where the shunting had no effect after the initial pressure was changed to 4 cmH2O. The lumbar epidural space CSF absorption test both on the operation day and during the follow-up period confirmed absorption in all patients. The L-L shunting is useful for patients with probable iNPH who are at high risk from general or lumbar anesthesia due to their systemic complications and age. CSF was continuously absorbed in the lumbar epidural space during postoperative follow-up period. A longer follow-up is required to establish this surgical procedure.

  17. Surgical removal of right-to-left cardiac shunt in the American alligator (Alligator mississippiensis) causes ventricular enlargement but does not alter apnoea or metabolism during diving

    Science.gov (United States)

    Eme, John; Gwalthney, June; Blank, Jason M.; Owerkowicz, Tomasz; Barron, Gildardo; Hicks, James W.

    2009-01-01

    SUMMARY Crocodilians have complete anatomical separation between the ventricles, similar to birds and mammals, but retain the dual aortic arch system found in all non-avian reptiles. This cardiac anatomy allows surgical modification that prevents right-to-left (R–L) cardiac shunt. A R–L shunt is a bypass of the pulmonary circulation and recirculation of oxygen-poor blood back to the systemic circulation and has often been observed during the frequent apnoeic periods of non-avian reptiles, particularly during diving in aquatic species. We eliminated R–L shunt in American alligators (Alligator mississippiensis) by surgically occluding the left aorta (LAo; arising from right ventricle) upstream and downstream of the foramen of Panizza (FoP), and we tested the hypotheses that this removal of R–L shunt would cause afterload-induced cardiac remodelling and adversely affect diving performance. Occlusion of the LAo both upstream and downstream of the FoP for ∼21 months caused a doubling of RV pressure and significant ventricular enlargement (average ∼65%) compared with age-matched, sham-operated animals. In a separate group of recovered, surgically altered alligators allowed to dive freely in a dive chamber at 23°C, occlusion of the LAo did not alter oxygen consumption or voluntary apnoeic periods relative to sham animals. While surgical removal of R–L shunt causes considerable changes in cardiac morphology similar to aortic banding in mammals, its removal does not affect the respiratory pattern or metabolism of alligators. It appears probable that the low metabolic rate of reptiles, rather than pulmonary circulatory bypass, allows for normal aerobic dives. PMID:19837897

  18. Use of a Javid™ shunt in the management of axillary artery injury as a complication of fracture of the surgical neck of the humerus: a case report

    Directory of Open Access Journals (Sweden)

    Suttie Stuart A

    2008-08-01

    Full Text Available Abstract Introduction Axillary artery injury is a rare but severe complication of fractures of the surgical neck of the humerus. Case presentation We present a case of axillary artery pseudoaneurysm secondary to such a fracture, in a 82-year-old white woman, presenting 10 weeks after the initial injury, successfully treated with subclavian to brachial reversed vein bypass together with simultaneous open reduction and internal fixation of the fracture. We discuss the use of a Javid™ shunt during combined upper limb revascularisation and open reduction and internal fixation of the fractured humerus. Conclusion This case highlights the usefulness of a Javid™ shunt, over other forms of vascular shunts, in prompt restoration of blood flow to effect limb salvage. It can be considered as a temporary measure whilst awaiting definitive revascularisation which can be performed following fracture fixation.

  19. Ateriovenous subclavia-shunt for head and neck reconstruction

    Directory of Open Access Journals (Sweden)

    Kübler Norbert R

    2008-11-01

    Full Text Available Abstract Reconstruction of the facial hard- and soft tissues is of special concern for the rehabilitation of patients especially after ablative tumor surgery has been performed. Impaired soft and hard tissue conditions as a sequelae of extensive surgical resection and/or radiotherapy may impede common reconstruction methodes. Even free flaps may not be used without interposition of a vein graft as recipient vessels are not available as a consequence of radical neck dissection. We describe the reconstruction of the facial hard- and soft tissues with a free parasacpular flap in a patient who had received ablative tumor surgery and radical cervical lymphadenectomy as a treatment regimen for squamous cell carcinoma (SCC. To replace the missing cervical blood vessels an arteriovenous subclavia-shunt using a saphena magna graft was created. Microvascular free flap transfer was performed as a 2-stage procedure two weeks after the shunt operation. The microvascular reconstructive technique is described in detail.

  20. Tentorial dural arteriovenous fistula successfully treated with surgical interruption of leptomeningeal venous drainage:a case report

    Institute of Scientific and Technical Information of China (English)

    LI Mei-hua; XU Geng-sheng; LI Yi-yun

    2005-01-01

    @@ Tentorial dural arteriovenous fistula (DAVF) is a rare disease, accounting for some 4% of all cases of intracranial DAVF.1 Because of a high risk of intracranial hemorrhage, patients with DAVF need aggressive treatment. Despite recent advances in endovascular technology, many researchers2-4 advocate open surgery for the treatment of tentorial DAVF. In this report, we present a case of tentorial DAVF with pure leptomeningeal venous drainage successfully treated by interruption of the draining vein.

  1. Transcatheter closure of a pulmonary arteriovenous malformation in a patient with hereditary hemorrhagic telangiectasia.

    Science.gov (United States)

    Parker, Christopher; Rousan, Talla A; Abu-Fadel, Mazen

    2015-07-01

    Pulmonary arteriovenous malformations (PAVM) are rare pulmonary vascular anomalies. Over 50 % of the cases are associated with hereditary hemorrhagic telangiectasia or Osler-Weber-Rendu Syndrome. Untreated PAVMs progressively enlarge and can cause significant right-to-left shunting. Surgical- and catheter-based approaches have been used in the management of PAVM. We report a case of a 74-year-old man who presented with dyspnea and hypoxia and was found to have a large right-sided PAVM. He underwent percutaneous closure of the PAVM with an Amplatzer device with significant improvement of his symptoms.

  2. Arteriovenous Fistula

    Science.gov (United States)

    ... home. Accessed Feb. 23, 2015. Vascular access for hemodialysis. National Kidney and Urologic Diseases Information Clearinghouse. http:// ... www.mayoclinic.org/diseases-conditions/arteriovenous-fistula/basics/definition/CON-20034876 . Mayo Clinic Footer Legal Conditions and ...

  3. Splenic arteriovenous fistula treated with percutaneous transarterial embolization

    DEFF Research Database (Denmark)

    Madsen, M.A.; Frevert, S.; Madsen, P.L.;

    2008-01-01

    Splenic arteriovenous fistula is a rare complication following splenectomy. We report a case of a large splenic arteriovenous fistula 23 years after splenectomy in a 50-year old male with abdominal pain, gastro-intestinal bleeding, ascites, diarrhoea, dyspnoea, portal hypertension and heart failure....... The arteriovenous fistula was successfully treated with percutaneous transarterial embolization and the patient gained almost complete recovery. This case demonstrates the usefulness of embolization of an otherwise surgical demanding arteriovenous fistula Udgivelsesdato: 2008/11...

  4. Syringosubarachnoid shunting using a myringotomy tube

    Directory of Open Access Journals (Sweden)

    Jack M Leschke

    2016-01-01

    Conclusion: We used a myringotomy tube for syringosubarachnoid shunting for the surgical management of a posttraumatic syrinx with good results. This technique minimizes suturing and may minimize shunt-related complications.

  5. The “focus on aneurysm” principle: Classification and surgical principles of management of concurrent arterial aneurysm with arteriovenous malformation causing intracranial hemorrhage

    Science.gov (United States)

    Jha, Vikas; Behari, Sanjay; Jaiswal, Awadhesh K.; Bhaisora, Kamlesh Singh; Shende, Yogesh P.; Phadke, Rajendra V.

    2016-01-01

    Context: Concurrent arterial aneurysms (AAs) occurring in 2.7-16.7% patients harboring an arteriovenous malformation (AVM) aggravate the risk of intracranial hemorrhage. Aim: We evaluate the variations of aneurysms simultaneously coexisting with AVMs. A classification-based management strategy and an abbreviated nomenclature that describes their radiological features is also proposed. Setting: Tertiary care academic institute. Statistics: Test of significance applied to determine the factors causing rebleeding in the groups of patients with concurrent AVM and aneurysm and those with only AVMs. Subjects and Methods: Sixteen patients (5 with subarachnoid hemorrhage and 11 with intracerebral/intraventricular hemorrhage; 10 with low flow [LF] and 6 with high flow [HF] AVMs) underwent radiological assessment of Spetzler Martin (SM) grading and flow status of AA + AVM. Their modified Rankin's score (mRS) at admission was compared with their follow-up (F/U) score. Results: Pre-operative mRS was 0 in 5, 2 in 6, 3 in 1, 4 in 3 and 5 in 1; and, SM grade I in 5, II in 3, III in 3, IV in 4 and V in 1 patients, respectively. AA associated AVMs were classified as: (I) Flow-related proximal (n = 2); (II) flow-related distal (n = 3); (III) intranidal (n = 5); (IV) extra-intranidal (n = 2); (V) remote major ipsilateral (n = 1); (VI) remote major contralateral (n = 1); (VII) deep perforator related (n = 1); (VIII) superficial (n = 1); and (IX) distal (n = 0). Their treatment strategy included: Flow related AA, SM I-III LF AVM: aneurysm clipping with AVM excision; nidal-extranidal AA, SM I-III LF AVM: Excision or embolization of both AA + AVM; nidal-extranidal and perforator-related AA, SM IV-V HF AVM: Only endovascular embolization or radiosurgery. Surgical decision-making for remote AA took into account their ipsilateral/contralateral filling status and vessel dominance; and, for AA associated with SM III HF AVM, it varied in each patient based on diffuseness of AVM nidus, flow

  6. Plasticity of motor function and surgical outcomes in patients with cerebral arteriovenous malformation involving primary motor area:insight from fMRI and DTI

    Institute of Scientific and Technical Information of China (English)

    Lijun Wang; Fuxin Lin; Jun Wu; Yuming Jiao; Yong Cao; Yuanli Zhao; Shuo Wang

    2016-01-01

    Background:Patients who have a cerebral arteriovenous malformation (cAVMs) in the motor cortex can have displaced function. The finding and its relationship to recovery from surgery is not known. Methods:We present the five cases with cAVMs involving precentral knob and/or paracentral lobule and without preoperative motor deficits. We used motor activation areas derived from Functional functional MRI (fMRI) as a region of interesting (ROI) to launch the plasticity of cerebrospinal tracts (CST). All the results were incorporated into the neuronavigation platform for surgical treatment. Intraoperative electric cortical stimulation (ECS) was used to map motor areas. Modified Rankin Scale (mRS) of hands and feets were performed on postoperative day 2, 7 and at month 3, 6 during follow-up period. All the patients suffered from motor deficits regardless of cortical activation patterns. Results:Three patients showed functionally seeded CST in or around the AVM, and were validated by intraoperative electrical stimulation (ECS). Patient 4 had two aberrant functionally seeded fiber tracts away from the lesion, but were proved to be non-functional by postoperative motor deficits. Patient 3 with motor cortex and fiber tract within a diffuse AVMs nidus, complete paralysis of upper extremity after operation and has a persistent motor deficit during 6-month follow-up period. Conclusions:The plasticity of motor cortex on fMRI doesn’t prevent post-operative motor deficits. Functionally mapped fiber tract within or abutting AVM nidus predicts transient and persistent motor deficit.

  7. Arteriovenous malformations in hereditary haemorrhagic telangiectasia: looking beyond ALK1-NOTCH interactions.

    Science.gov (United States)

    Peacock, Hanna M; Caolo, Vincenza; Jones, Elizabeth A V

    2016-02-01

    Hereditary haemorrhagic telangiectasia (HHT) is characterized by the development of arteriovenous malformations--enlarged shunts allowing arterial flow to bypass capillaries and enter directly into veins. HHT is caused by mutations in ALK1 or Endoglin; however, the majority of arteriovenous malformations are idiopathic and arise spontaneously. Idiopathic arteriovenous malformations differ from those due to loss of ALK1 in terms of both location and disease progression. Furthermore, while arteriovenous malformations in HHT and Alk1 knockout models have decreased NOTCH signalling, some idiopathic arteriovenous malformations have increased NOTCH signalling. The pathogenesis of these lesions also differs, with loss of ALK1 causing expansion of the shunt through proliferation, and NOTCH gain of function inducing initial shunt enlargement by cellular hypertrophy. Hence, we propose that idiopathic arteriovenous malformations are distinct from those of HHT. In this review, we explore the role of ALK1-NOTCH interactions in the development of arteriovenous malformations and examine a possible role of two signalling pathways downstream of ALK1, TMEM100 and IDs, in the development of arteriovenous malformations in HHT. A nuanced understanding of the precise molecular mechanisms underlying idiopathic and HHT-associated arteriovenous malformations will allow for development of targeted treatments for these lesions.

  8. Intravenous digital subtraction angiography in the assessment of patients with left to right shunts before and after surgical correction

    Energy Technology Data Exchange (ETDEWEB)

    Yiannikas, J.; Moodie, D.S.; Gill, C.C.; Sterba, R.; McIntyre, R.; Buonocore, E.

    1984-06-01

    Pre- and postoperative structural changes and pulmonary to systemic flow (QP/QS) ratios were assessed using digital angiography in 34 patients documented to have a left to right shunt at cardiac catheterization. There were 16 men and 18 women whose ages ranged from 4 months to 60 years. The radiographic single mask mode was used for all digital subtraction angiographic studies with a typical radiographic sequence being 80 to 100 kV, 5 to 10 mA/frame at six frames/s for 15 seconds. Renografin-76 was used as a bolus injection at 0.5 to 1.0 ml/kg via an arm vein in most patients. The level of the left to right shunt and any associated anomalies were noted and compared with results from cardiac catheterization. Digital subtraction angiographic flow curves were generated from the pulmonary arteries, and QP/QS ratios were calculated pre- and postoperatively using the gamma variate fit method and compared with the QP/QS ratio from first pass radionuclide studies. A strong correlation between preoperative digital subtraction angiographically derived QP/QS ratio and radionuclide-derived QP/QS ratio was found, with an r value equal to 0.89, p less than 0.0001. Postoperatively, all patients had a QP/QS ratio less than 1.2:1.0 for both digital subtraction angiography and radionuclide studies. The level of left to right shunt was accurately assessed in all patients, and its absence observed postoperatively. Associated anomalies, such as a persistent left superior vena cava, coarctation of the aorta and partial anomalous venous return, were identified in all cases.

  9. Notch-1 Signalling Is Activated in Brain Arteriovenous Malformations in Humans

    Science.gov (United States)

    ZhuGe, Qichuan; Zhong, Ming; Zheng, WeiMing; Yang, Guo-Yuan; Mao, XiaoOu; Xie, Lin; Chen, Gourong; Chen, Yongmei; Lawton, Michael T.; Young, William L.; Greenberg, David A.; Jin, Kunlin

    2009-01-01

    A role for the Notch signalling pathway in the formation of arteriovenous malformations during development has been suggested. However, whether Notch signalling is involved in brain arteriovenous malformations in humans remains unclear. Here, we performed immunohistochemistry on surgically resected brain arteriovenous malformations and found that,…

  10. Perkutan transluminal embolisering af pulmonale arteriovenøse misdannelser

    DEFF Research Database (Denmark)

    Kjeldsen, A D; Andersen, P E; Oxhøj, H

    1998-01-01

    A series of nine patients with pulmonary arteriovenous malformations (PAVM) treated with embolotherapy at Odense University Hospital is presented. In all patients the arterial oxygen tension increased after embolisation. PAVM causes right-to-left shunting, which may result in severe hypoxaemia, and...

  11. Stent-graft repair of a recurrent popliteal arteriovenous fistula

    NARCIS (Netherlands)

    Tielliu, IFJ; Verhoeven, ELG; Prins, TR; van Det, M; van den Dungen, JJAM

    2002-01-01

    Purpose: To describe the successful endovascular treatment of a popliteal arteriovenous fistula with a stent-graft. Case Report: A 54-year-old man was referred to our hospital with a distal popliteal arteriovenous fistula following an arthroscopic meniscectomy 6 years earlier. Three surgical attempt

  12. Ventriculoperitoneal shunt complications needing shunt revision in children: A review of 5 years of experience with 48 revisions

    Directory of Open Access Journals (Sweden)

    Rajendra K Ghritlaharey

    2012-01-01

    Full Text Available Background: The aim of this study was to review the management of ventriculoperitoneal (VP shunt complications in children. Patients and Methods: During the last 5 years (January 1, 2006 to December 31, 2010, 236 VP shunt operations were performed in children under 12 years of age; of these, 40 (16.94% developed shunt complications and those who underwent VP shunt revisions were studied. Results: This prospective study included 40 (28 boys and 12 girls children and required 48 shunt revisions. Complications following VP shunts that required shunt revisions were peritoneal catheter/peritoneal end malfunction (18, shunt/shunt tract infections (7, extrusion of peritoneal catheter through anus (5, ventricular catheter malfunction (4, cerebrospinal fluid (CSF leak from abdominal wound (4, shunt system failure (2, ventricular end/shunt displacement (2, CSF pseudocysts peritoneal cavity (2, extrusion of peritoneal catheter from neck, chest, abdominal scar and through umbilicus, one each. Four-fifth of these shunt complications occurred within 6 months of previous surgery. Surgical procedures done during shunt revisions in order of frequency were revision of peritoneal part of shunt (27, 56.25%, revision of entire shunt system (6, 12.5%, extra ventricular drainage and delayed re-shunt (5, 10.41%, shunt removal and delayed re-shunt (5, 10.41%, opposite side shunting (2, 4.16%, cysts excision and revision of peritoneal catheter (2, 4.16% and revision of ventricular catheter (1, 2.08%. The mortalities following VP shunt operations were 44 (18.64% and following shunt revisions were 4 (10%. Conclusions: VP shunt done for hydrocephalus in children is not only prone for complications and need for revision surgery but also associated with considerable mortality.

  13. Urokinase treatment for arteriovenous fistulae declotting in dialyzed patients.

    Science.gov (United States)

    Mangiarotti, G; Canavese, C; Thea, A; Segoloni, G P; Stratta, P; Salomone, M; Vercellone, A

    1984-01-01

    Urokinase treatment, previously employed with success in the declotting of deep venous thrombosis and arteriovenous shunts in patients undergoing regular dialytic treatment (RDT), was used in 23 cases of arteriovenous fistula thrombotic occlusion in 18 RDT patients. The treatment was successful in 65.2% of the cases without any negative side effects, except 1 case which may have developed a pulmonary embolism. Patients with severe hypofibrinolysis may need larger doses or may have a recurrence of the thrombotic episode. All therapeutic failures correlated with the presence of fibrosis or sclerosis.

  14. Optimizing Arteriovenous Fistula Maturation

    OpenAIRE

    2009-01-01

    Autogenous arteriovenous fistulas are the preferred vascular access in patients undergoing hemodialysis. Increasing fistula prevalence depends on increasing fistula placement, improving the maturation of fistula that fail to mature and enhancing the long-term patency of mature fistula. Percutaneous methods for optimizing arteriovenous fistula maturation will be reviewed.

  15. Direct percutaneous venous puncture and embolization of giant perimedullary arteriovenous fistulas.

    Science.gov (United States)

    Casasco, A; Guimaraens, L; Cuellar, H; Theron, J; Heredero, J

    2011-01-01

    PMAVFs are rare entities that are formed by a direct communication between an artery that feeds the spinal cord and a vein. The goal of treatment is to occlude the shunt; this is done endovascularly either from an arterial or a venous approach. When these approaches are not possible, direct percutaneous puncture of the draining veins may be attempted to embolize the arteriovenous shunt directly.

  16. Complications after surgical attenuation of congenital extrahepatic portosystemic shunts in dogs can be prevented by intraoperative Doppler ultrasonographic assessment of portal hemodynamics

    NARCIS (Netherlands)

    Szatmári, Viktor

    2005-01-01

    Under normal circumstances the blood from the gastrointestinal tract flows via the portal vein to the liver. The detoxified blood leaves the liver via the hepatic veins to the caudal vena cava, which latter enters the heart. Portosystemic shunting occurs when an anomalous vein allows the portal bloo

  17. Platypnea-Orthodeoxia Syndrome: To Shunt or Not to Shunt, That is the Question.

    Science.gov (United States)

    Klein, Michael R; Kiefer, Todd L; Velazquez, Eric J

    2016-06-01

    Platypnea-orthodeoxia syndrome is a rare disease defined by dyspnea and deoxygenation, induced by an upright position, and relieved by recumbency. Causes include shunting through a patent foramen ovale and pulmonary arteriovenous malformations. A 79-year-old woman experienced 2 syncopal episodes at rest and presented at another hospital. In the emergency department, she was hypoxic, needing 6 L/min of oxygen. Her chest radiograph showed nothing unusual. Transthoracic echocardiograms with saline microcavitation evaluation were mildly positive early after agitated-saline administration, suggesting intracardiac shunting. She was then transferred to our center. Right-sided heart catheterization revealed no oximetric evidence of intracardiac shunting while the patient was supine and had a low right atrial pressure. However, her oxygen saturation dropped to 78% when she sat up. Repeat transthoracic echocardiography while sitting revealed a dramatically positive early saline microcavitation-uptake into the left side of the heart. Transesophageal echocardiograms showed a patent foramen ovale, with right-to-left shunting highly dependent upon body position. The patient underwent successful percutaneous patent foramen ovale closure, and her oxygen supplementation was suspended. In patients with unexplained or transient hypoxemia in which a cardiac cause is suspected, it is important to evaluate shunting in both the recumbent and upright positions. In this syndrome, elevated right atrial pressure is not necessary for significant right-to-left shunting. Percutaneous closure, if feasible, is first-line therapy in these patients.

  18. Ventriculoperitoneal Shunting Surgery with Open Distal Shunt Catheter Placement in the Treatment of Hydrocephalus.

    Science.gov (United States)

    Zhang, Yang; Zhu, Xiaobo; Zhao, Jinchuan; Hou, Kun; Gao, Xianfeng; Sun, Yang; Wang, Wei; Zhang, Xiaona

    2015-11-01

    Ventriculoperitoneal shunting (VPS) is a major therapy for hydrocephalus, but has a significant risk of device malfunctioning. In this study, we explored a novel distal shunt catheter placement method in VPS for the treatment of hydrocephalus. Five patients with different etiologies of hydrocephalus underwent VPS with open distant shunt catheter attached outside. We analyzed different variables (age, gender, medical history, clinical presentation, indication for surgery and surgical technique, postoperative complications) and occurrence of shunt failure and infection. All hydrocephalus patients who received the distal shunt catheter placed outside can undergo regular VPS again after the condition improves. The modified VPS in the treatment of hydrocephalus with the distal shunt catheter placed outside could potentially reduce the necessity of repeat surgery for addressing the complications caused by catheter obstruction and infections, reduce the chance of adhesions, and would be of benefit to those patients who need future revisions.

  19. Middle Meningeal Arteriovenous Fistula and Its Spontaneous Closure: A Case Report and Review of the Literature

    OpenAIRE

    2007-01-01

    Middle meningeal artery pseudo-aneurysms and arteriovenous fistulas are usually post-traumatic, although occasional iatrogenic cases have been reported. The treatment has been obliteration of the fistula by surgical or endovascular means. Spontaneous closure of fistula is uncommon. We report a case of non-traumatic middle meningeal arteriovenous fistula in a patient with alcoholism, which resolved spontaneously without treatment.

  20. Notch receptor expression in human brain arteriovenous malformations.

    Science.gov (United States)

    Hill-Felberg, Sandra; Wu, Hope Hueizhi; Toms, Steven A; Dehdashti, Amir R

    2015-08-01

    The roles of the Notch pathway proteins in normal adult vascular physiology and the pathogenesis of brain arteriovenous malformations are not well-understood. Notch 1 and 4 have been detected in human and mutant mice vascular malformations respectively. Although mutations in the human Notch 3 gene caused a genetic form of vascular stroke and dementia, its role in arteriovenous malformations development has been unknown. In this study, we performed immunohistochemistry screening on tissue microarrays containing eight surgically resected human brain arteriovenous malformations and 10 control surgical epilepsy samples. The tissue microarrays were evaluated for Notch 1-4 expression. We have found that compared to normal brain vascular tissue Notch-3 was dramatically increased in brain arteriovenous malformations. Similarly, Notch 4 labelling was also increased in vascular malformations and was confirmed by western blot analysis. Notch 2 was not detectable in any of the human vessels analysed. Using both immunohistochemistry on microarrays and western blot analysis, we have found that Notch-1 expression was detectable in control vessels, and discovered a significant decrease of Notch 1 expression in vascular malformations. We have demonstrated that Notch 3 and 4, and not Notch 1, were highly increased in human arteriovenous malformations. Our findings suggested that Notch 4, and more importantly, Notch 3, may play a role in the development and pathobiology of human arteriovenous malformations.

  1. [Cerebrospinal fluid shunts for hydrocephalus and related disorders].

    Science.gov (United States)

    Ito, Masaki; Houkin, Kiyohiro; Saito, Hisayasu; Shimbo, Daisuke; Motegi, Hiroaki; Kawabori, Masahito; Miyamoto, Michiyuki; Yamauchi, Tomohiro

    2012-10-01

    Cerebrospinal fluid (CSF) shunts are commonly employed to treat patients with hydrocephalus. A large number of papers have been published focusing on complications and failures of CSF shunts. However, there appears to be a paucity of knowledge comprehensively covering both common complications and rare ones. In this systematic review, we surveyed articles about surgical complications of CSF shunts as comprehensively as possible. Quantitative analysis was performed to determine the frequency of well-known complications, mortality and revision rates of CSF shunts. Furthermore, rare complications of CSF shunts have also been reviewed.

  2. Episodic ventriculomegaly due to hypernatremia mimicking shunt malfunction: case report.

    Science.gov (United States)

    Jernigan, Sarah C; Stone, Scellig S D; Aronson, Joshua P; Putman, Melissa; Proctor, Mark R

    2015-10-01

    Patients with shunted hydrocephalus presenting with altered mental status and ventriculomegaly are generally considered to be in shunt failure requiring surgical treatment. The authors describe a case of shunted hydrocephalus secondary to a disseminated neuroectodermal tumor in a pediatric patient in whom rapid fluctuations in sodium levels due to diabetes insipidus repeatedly led to significant changes in ventricle size, with invasively confirmed normal shunt function and low intracranial pressure. This clinical picture exactly mimics shunt malfunction, requires urgent nonsurgical therapy, and underscores the importance of considering serum osmolar abnormalities in the differential diagnosis for ventriculomegaly.

  3. Summary of the surgical procedures of Rex shunt and Warren shunt in 8 cases of cavernous transfor-mation of portal vein%分流手术治疗门脉海绵样变8例临床分析

    Institute of Scientific and Technical Information of China (English)

    孔艳霞; 张大; 杨合英; 王家祥; 贾佳; 赵鸽; 岳铭

    2015-01-01

    Objetive the outcomes and possible complications of surgical procedures of Rex shunt and Warren shunt in 8 cases of cavernous transformation of portal vein. Methods 8 cases who underwent the shunt surgery for cavernous transformation of portal vein from December 2012 to January 2015 were reviewed, including 5 patients having Rex shunt (2 cases of them had recurrent bleeding after devascularization proce-dures),and 3 having Warren shunt.All cases had recurrent upper gastrointestinal hemorrhage(more than twice per year).Upper gastrointestinal contrast studies helped delineate the extent of esophageal and gastric varices and cavernous transformation of portal vein was confirmed by color Doppler ultrasound and CT.In Rex proce-dures,the isolated coronary veins were sewn to the intrahepatic portalvein in the recessus of Rex,meanwhile, the portal vein pressures were measured during vascular anastomosis to assure the relief of portal hypertension after the process.While in Warren shunt,the varices were decompressed by allowing them to drain via the splenic vein into the left renal vein,the portal vein pressures were obtained as well. Results Patients were followed up for 6 to 31 months.Growth and development was the same for all patients within the same age group,and no cases present with encephalopathy;1 case had recurrent bleeding after 16 months of the opera-tions;mesenteric venous thrombosis occurred in one case and was cured through thrombolysis and anticoagula-tion therapy;1 case with infraction of spleen had fever for one month.Conclusions Shunt precedures are effec-tive to treat cavernous transformation of portal vein and prevent the gastrointestinal bleeding while with limited complications.%目的:总结 Rex 分流术及 Warren 分流术治疗8例门静脉海绵样变的效果及并发症。方法2012年12月至2015年1月作者采用分流手术治疗门静脉海绵样变8例,其中 Rex 分流手术5例(2例为断流手术后出血复发),Warren

  4. DSA by means of fine-needle puncture for excluding vascular complications in haemodialysis shunts

    Energy Technology Data Exchange (ETDEWEB)

    Alart, I.P.; Merk, J.; Eichner, H.

    1985-06-01

    The article on hand presents the experience gained with examinations of Cimino haemodialysis shunts using digital substraction angiography (DSA). Angiographic results after arterial and venous fine-needle puncture show - particularly in arterial DSA - the advantage of excellent contrasting of the afferent arterial vessel, of the arterio-venous anastomosis and of the venous return while allowing safe diagnosis. This examination procedure is low in complications for the patient, is suitable for outpatients and has numerous advantages over transvenous shunt DSA.

  5. Ventriculoperitoneal shunt in cryptococcal meningitis with hydrocephalus.

    Science.gov (United States)

    Tang, L M

    1990-05-01

    Fourteen patients with cryptococcal meningitis were reviewed. All patients had a ventriculoperitoneal shunt for hydrocephalus. Early recognitions and prompt relief of hydrocephalus were useful for eight patients who showed rapid deterioration of consciousness or signs of cerebral herniation. There was no surgical response in four patients who had had weeks of confusion or mental change. It seems, therefore, that the duration of disturbance of consciousness or change of mentality before shunting is critical in determination of the outcome of the treatment. Ventricular shunting was effective in relieving papilledema in five patients. However, the surgery did not prevent the development of papilledema to optic atrophy and subsequent blindness in two patients. Hence, in addition to hydrocephalus with increased intracranial pressure, conditions such as direct invasion of the optic pathways by Cryptococcus neoformans or optochiasmatic arachnoiditis may be responsible for the visual failure. Ventricular shunting was also helpful in restoring paraparesis in one patient. Of the cerebrospinal fluid determinations, low protein concentration was a favorable indicator for surgery. Of the seven patients who received the surgical procedure before the start of antifungal therapy, four showed a significant improvement despite active infection of the central nervous system. None of the seven patients deteriorated because of the surgical operation. Thus, active stage of cryptococcal meningitis does not contraindicate the necessity of shunting, and premedication with antifungal drugs is unnecessary. Also, no shunt-related morbidity and mortality was seen in this study.

  6. Intraparenchymal pericatheter cyst following disconnection of ventriculoperitoneal shunt system

    Directory of Open Access Journals (Sweden)

    S Balasubramaniam

    2013-01-01

    Full Text Available Ventriculoperitoneal (VP shunt is one of the most commonly performed procedures in neurosurgery, but it is also the procedure, which is most prone to complications. Spread of cerebrospinal fluid (CSF into the brain parenchyma is a rare complication of VP shunt and can take the form of CSF edema or a porencephalic cyst. We describe a case of a 1½-year-old child who presented to us with seizures. Computed tomography scan revealed pericatheter porencephalic cyst. Surgical exploration revealed a disconnected VP shunt system. Patient was neurologically observed after shunt extraction. He was seizure free and radiological follow-up showed resolution of cyst. Ours is the first case to document the presence of pericatheter cyst following complete disconnection of shunt system. Though shunt revision is the accepted treatment modality, careful neurological observation can be done after shunt removal especially in asymptomatic cases with compensated hydrocephalus.

  7. Combined spinal intramedullary arteriovenous malformation and lipomyelomeningocele

    Energy Technology Data Exchange (ETDEWEB)

    Weon, Y.C.; Roh, H.G.; Byun, H.S. [Samsung Medical Center, Sungkyunkwan University School of Medicine, Department of Radiology, Seoul (Korea); Chung, J.I. [Medimoa Hospital, Department of Radiology, Seoul (Korea); Eoh, W. [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea)

    2005-10-01

    Combined spinal arteriovenous malformation and lipomyelomeningocele are extremely rare. We present a rare combined case of a lipomyelomeningocele with an intramedullary arteriovenous malformation (AVM) occurred at the L3-L4 level in a 30-year-old man who suffered from low back pain radiating to the lower extremities, dysuria, and frequency for 5 years. The MR studies showed an intradural mass with high-signal intensity on both T1-weighted and T2-weighted images, intermingled with multiple signal-void structures. The mass extended extradurally toward a subcutaneously forming fatty mass on the patient's back. Spinal angiography showed an AVM supplied by the radiculopial branches of the lumbar arteries and drained by tortuous, dilated, perimedullary veins. Endovascular embolization and surgical resection were performed. (orig.)

  8. Pulmonary arteriovenous malformations: overview and transcatheter embolotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Pugash, R.A. [Univ. of Toronto, St. Michael' s Hospital, Dept. of Medical Imaging, Toronto, Ontario (Canada)

    2001-04-01

    The majority of pulmonary arteriovenous malformations (pAVMs) are found in people with hereditary hemorrhagic telangiectasia (HHT), a condition also known as Osler-Weber-Rendu syndrome. HHT is a clinically heterogeneous autosomal dominant disorder in which abnormal blood vessels cause bleeding and arteriovenous shunting. The 2 basic lesions of HHT - telangiectasias and arteriovenous malformations (AVMs) - are closely related. Multisystem involvement leads to a staggering array of clinical manifestations, making HHT one of medicine's less familiar 'great pretenders'. Telangiectasias are dilated blood vessels, typically located in mucocutaneous surfaces (i.e., skin, conjunctiva, respiratory tract, gastrointestinal tract, urinary tract). Small telangiectasias are simply dilated post-capillary venules, whereas larger telangiectasias are made up of dilated arterioles and venules, often with no intervening capillary. They are, in essence, diminutive AVMs. These tiny lesions are visible as punctate bright red spots on skin and mucosal surfaces (Fig. 1). Their fragility and superficial location account for the disabling epistaxis and chronic gastrointestinal bleeding, which are so common with HHT. Hematuria (caused by urothelial telangiectasias) occurs occasionally but is not a prominent feature of the disease. Although tracheobronchial telangiectasias do occur and may cause hemoptysis, severe hemoptysis is typically related to pAVM rupture. AVMs are direct artery-to-vein connections. Though larger and far more impressive radiologically than telangiectasias, AVMs are more likely to be clinically silent until they either declare themselves in a catastrophic fashion or are detected by screening tests. In contrast to telangiectasias, which are generally found in epithelial surfaces, AVMs tend to develop within organs, most commonly the lung and brain. As screening methods evolve, liver involvement with both telangiectasias and complex AVMs is being recognized

  9. Appendicitis Presenting Concurrently with Cecal Arteriovenous Malformation in a Child

    Directory of Open Access Journals (Sweden)

    Sahil P Parikh

    2015-09-01

    Full Text Available Acute appendicitis is a commonly diagnosed surgical problem in the pediatric population. Arterio-venous malformations (AVM of the colonic tract are rarely reported in the pediatric literature. A 13-year old boy who presented with acute appendicitis with concurrent cecal AVM is reported in whom appendectomy was done. Later on radiological investigations AVM was confirmed.

  10. Congenital subclavian arteriovenous malformation causing cardiac failure in an adult.

    Science.gov (United States)

    Anoop, T M; Sreejith, P; Thomas, Joby K; Gailin, B; Jabbar, P K; Ittycheria, Cherian C; George, Raju

    2009-07-01

    Congenital arteriovenous malformations (AVMs) of the thoracic region are rarely reported in adults. The authors report an unusual case of a 30-year-old man who presented with a large congenital AVM and heart failure. The diagnosis was made using transthoracic Doppler echocardiography and computed tomography. Embolization followed by surgical resection of the AVM resulted in the prompt relief of heart failure.

  11. [Right renal arteriovenous fistula after nephrectomy with streptococcal endarteritis].

    Science.gov (United States)

    Natali, J; Emerit, J; Reynier, P; Maraval, M

    1975-01-18

    The authors add a new case, to the 41 already published, of arterio-venous fistula of the renal pedicle after nephrectomy, with the peculiarity of its presentation as a prolonged fever resulting from streptococcal bacterial endarteritis at the site of the fistula (3rd case in the literature). Surgical treatment in association with massive and prolonged antibiotic therapy resulted in recovery.

  12. Perfusion-weighted MRI of spinal dural arteriovenous fistula

    Energy Technology Data Exchange (ETDEWEB)

    Yanaka, K.; Matsumaru, Y.; Uemura, K.; Matsumura, A.; Nose, T. [Department of Neurosurgery, Institute of Clinical Medicine, University of Tsukuba, Ibaraki (Japan); Anno, I. [Department of Radiology, Institute of Clinical Medicine, University of Tsukuba, Ibaraki (Japan)

    2003-10-01

    A 72-year-old woman was admitted with rapidly progressive paraplegia and sphincter disturbance. T2-weighted images of the thoracic spine showed intramedullary high signal with flow voids suggesting dilated medullary veins. Conventional spinal angiography demonstrated a dural arteriovenous fistula draining into perimedullary veins. Perfusion-weighted MRI demonstrated a prolonged mean transit time and increased blood volume in the high-signal area. The loss of normal perfusion gradient and venous hypertension and were thought to produce these differences. The time-to-peak was almost identical in the high-signal and isointense areas, although the bolus of contrast medium arrived earlier in the former. Arteriovenous shunting was thought to cause faster inflow. These changes may have resulted in increased blood volume in the spinal cord. The high signal has been attributed to oedema due to venous congestion, but there has been no histological confirmation. Perfusion MRI in this case supports this hypothesis. (orig.)

  13. Arterio-venous malformations of uterus - diagnostic and management dilemmas.

    Science.gov (United States)

    Narang, H K; Puri, M; Patra, S; Trivedi, S S

    2015-01-01

    Keeping in mind the life-threatening consequences of curettage in cases of undiagnosed uterine arterio-venous malformation (AVM), its possibility should be considered in patients presenting with abnormal heavy uterine bleeding and negative Human Chorionic Gonadotropin (β-hCG) values. We collected a series of cases in which the patients presented with abnormal heavy uterine bleeding, some not responding to conservative treatment. In the presence of declining or low serum β-hCG levels and ultrasound Doppler showing increased vascularity, patients were investigated to detect the possible presence of uterine AVM. In those patients in whom angiographic confirmation of uterine AVM was made, embolisation was done and the outcome was followed. In those patients in whom hysterectomy was done the histopathogy specimen was studied for the possible cause of increased vascularity. Arterio-venous shunting seen on ultrasound does not always imply a uterine AVM and some cases can present diagnostic and management dilemmas.

  14. Malformación arteriovenosa pulmonar: Características clínicas, diagnóstico y rol del tratamiento quirúrgico en pacientes tratados con cirugía resectiva pulmonar Pulmonary arteriovenous malformation: Clinical features, diagnosis and role of surgical management in patients with lung resection surgery

    Directory of Open Access Journals (Sweden)

    ROBERTO GONZÁLEZ L

    2011-03-01

    Full Text Available Introducción: Las malformaciones arteriovenosas pulmonares (MAVP son infrecuentes y la cirugía tiene un rol en casos seleccionados. Objetivos: Describir las características clínicas, métodos diagnósticos y rol del tratamiento quirúrgico en pacientes tratados con cirugía por MAVP. Materialy Método: Revisión retrospectiva, incluyendo todos los pacientes con diagnóstico de MAVP en quienes se realizó cirugía en el Instituto Nacional del Tórax, desde febrero de 2005 a febrero de 2010. El seguimiento fue por control médico o contacto telefónico. Resultados: Se analizó 8 pacientes, seis mujeres (relación 3:1, edad entre 16 y 68 años. Los síntomas y signos más frecuentes fueron: disnea, cianosis y acropaquia. La localización más frecuente fue el lóbulo inferior derecho. Cuatro pacientes tenían MAVP múltiples y cuatro cumplían con criterios de Enfermedad de Rendu-Osler-Weber Seis tenían policitemia y dos anemia. La radiografía fue anormal en todos los casos y la tomogrqfía computada definió la anatomía en siete. Angiogrqfia se realizó en tres casos. Dos tenían ecocardiograma con contraste y cuatro cintigrama. La cirugía más frecuente fue la lobectomía. La indicación de cirugía fue: tamaño de la MAVP en cinco, falla de embolización en dos y hallazgo intra operatorio en uno, intervenido por otra razón. Uno presentó hemorragia post-operatoria. La estadía post-operatoria fue entre 2 y 10 días. No hubo mortalidad. En el último control todos los pacientes estaban asintomáticos. Conclusión: Las MAVPpueden presentarse en un amplio espectro clínico y anatómico. Pueden generar síntomas y complicaciones graves, por esto se recomienda tratarlas. El estudio pre-operatorio se basa en demostrar el shunt y en determinar las características anatómicas de la lesión. En algunos casos seleccionados está indicada la cirugía resectiva pulmonar.Background: Pulmonary arteriovenous malformations (PA VM are rare and surgery

  15. Right Ventricular Enlargement within Months of Arteriovenous Fistula Creation in 2 Hemodialysis Patients.

    Science.gov (United States)

    Ragupathi, Loheetha; Johnson, Drew; Marhefka, Gregary D

    2016-08-01

    Surgically created arteriovenous fistulae (AVF) for hemodialysis can contribute to hemodynamic changes. We describe the cases of 2 male patients in whom new right ventricular enlargement developed after an AVF was created for hemodialysis. Patient 1 sustained high-output heart failure solely attributable to the AVF. After AVF banding and subsequent ligation, his heart failure and right ventricular enlargement resolved. In Patient 2, the AVF contributed to new-onset right ventricular enlargement, heart failure, and ascites. His severe pulmonary hypertension was caused by diastolic heart failure, diabetes mellitus, and obstructive sleep apnea. His right ventricular enlargement and heart failure symptoms did not improve after AVF ligation. We think that our report is the first to specifically correlate the echocardiographic finding of right ventricular enlargement with AVF sequelae. Clinicians who treat end-stage renal disease patients should be aware of this potential sequela of AVF creation, particularly in the upper arm. We recommend obtaining preoperative echocardiograms in all patients who will undergo upper-arm AVF creation, so that comparisons can be made postoperatively. Alternative consideration should be given to creating the AVF in the radial artery, because of less shunting and therefore less potential for right-sided heart failure and pulmonary hypertension. A multidisciplinary approach is optimal when selecting patients for AVF banding or ligation.

  16. Unique double recurrence of cerebral arteriovenous malformation.

    Science.gov (United States)

    Nagm, Alhusain; Horiuchi, Tetsuyoshi; Ichinose, Shunsuke; Hongo, Kazuhiro

    2015-09-01

    Surgically treated patients with arteriovenous malformations (AVMs) are considered cured when the postoperative angiogram proves complete resection. However, despite no residual nidus or early draining vein on postoperative angiogram, rare instances of AVM recurrence have been reported in adults. In this paper, the authors present a case of a 24-year-old woman with asymptomatic double recurrence of her cerebral AVM after angiographically proven complete resection. To the authors' knowledge, this patient represents the first case with double de novo asymptomatic recurrence of Spetzler-Martin grade I AVM. Also, she represents the first case with unique AVM criteria in each recurrence.

  17. Treatment of Portosystemic Shunt Myelopathy with a Stent Graft Deployed through a Transjugular Intrahepatic Route

    Energy Technology Data Exchange (ETDEWEB)

    Jain, Deepak, E-mail: deepakjain02@yahoo.com; Arora, Ankur, E-mail: aroradrankur@yahoo.com [Institute of Liver and Biliary Sciences, Department of Radiology (India); Deka, Pranjal, E-mail: drpranjaldeka@gmail.com [Institute of Liver and Biliary Sciences, Department of Hepatopancreatobiliary Surgery (India); Mukund, Amar, E-mail: dramarmukund@gmail.com; Bhatnagar, Shorav, E-mail: drshorav@yahoo.com [Institute of Liver and Biliary Sciences, Department of Radiology (India); Jindal, Deepti, E-mail: deepijindal@rediffmail.com; Kumar, Niteen, E-mail: drniteenkumar@gmail.com; Pamecha, Viniyendra, E-mail: viniyendra@yahoo.co.uk [Institute of Liver and Biliary Sciences, Department of Hepatopancreatobiliary Surgery (India)

    2013-08-01

    A case of surgically created splenorenal shunt complicated with shunt myelopathy was successfully managed by placement of a stent graft within the splenic vein to close the portosystemic shunt and alleviate myelopathy. To our knowledge, this is the first report of a case of shunt myelopathy in a patient with noncirrhotic portal fibrosis without cirrhosis treated by a novel technique wherein a transjugular intrahepatic route was adopted to deploy the stent graft.

  18. Hypersexuality from resection of left occipital arteriovenous malformation.

    Science.gov (United States)

    Cao, Yong; Zhu, Zhaohui; Wang, Rong; Wang, Shuo; Zhao, Jizong

    2010-01-01

    The authors report their experience on one patient with hypersexuality from resection of left occipital arteriovenous malformation. To the best of our knowledge, this is the first case reported in the literature. A 35-year-old right-handed female farmer suffered a sudden left occipital hemorrhage with subarachnoid and subdural hemorrhages of the left hemisphere. Transient left uncal herniation occurred at the onset and was released by conservative treatment. Digital subtraction angiography showed a brain left occipital arteriovenous malformation. After microsurgical resection of the arteriovenous malformation, the patient developed hypersexual behavior. Positron emission tomography showed hypermetabolism in the left frontal region and left posterior hippocampal gyrus and hypometabolism in the left anterior hippocampal gyrus and the left occipital surgical area. Theories concerning normal pressure perfusion breakthrough and specific areas in the brain responsible for the human sexual response are discussed.

  19. Treatment of syringomyelia with a syringosubarachnoid shunt.

    Science.gov (United States)

    Tator, C H; Briceno, C

    1988-02-01

    The surgical results in 40 patients with syringomyelia, treated with a syringosubarachnoid shunt or other procedures are reviewed. The principal indication for surgery was that of significant neurological deterioration. There were 12 patients with idiopathic syringomyelia without tonsillar ectopia, 12 with an associated Chiari malformation, 11 with post-traumatic syringomyelia and five patients with spinal arachnoiditis. There were 38 syringosubarachnoid shunts performed in 35 patients, and an excellent or good result was achieved in 26 patients (74.3%). In terms of the type of syringomyelia, the best results were obtained in the idiopathic group without tonsillar ectopia and in the post-traumatic group. A short duration of pre-operative symptoms favoured a better outcome, and in our opinion, early surgical treatment is indicated for all patients with neurological deterioration. All eight patients in whom a posterior fossa decompression was performed as the initial surgical procedure required a second operation, either a syringosubarachnoid or syringoperitoneal shunt to achieve neurological improvement or stabilization. Thus, the syringosubarachnoid shunt is an effective therapeutic modality for patients with syringomyelia, particularly for the idiopathic and post-traumatic groups. More than one surgical procedure may be required to achieve cessation of deterioration. Overall, excellent or good results were achieved in 29 (72.5%) of the 40 patients.

  20. Endoscopic Third Ventriculostomy in Previously Shunted Children

    Directory of Open Access Journals (Sweden)

    Eva Brichtova

    2013-01-01

    Full Text Available Endoscopic third ventriculostomy (ETV is a routine and safe procedure for therapy of obstructive hydrocephalus. The aim of our study is to evaluate ETV success rate in therapy of obstructive hydrocephalus in pediatric patients formerly treated by ventriculoperitoneal (V-P shunt implantation. From 2001 till 2011, ETV was performed in 42 patients with former V-P drainage implantation. In all patients, the obstruction in aqueduct or outflow parts of the fourth ventricle was proved by MRI. During the surgery, V-P shunt was clipped and ETV was performed. In case of favourable clinical state and MRI functional stoma, the V-P shunt has been removed 3 months after ETV. These patients with V-P shunt possible removing were evaluated as successful. In our group of 42 patients we were successful in 29 patients (69%. There were two serious complications (4.7%—one patient died 2.5 years and one patient died 1 year after surgery in consequence of delayed ETV failure. ETV is the method of choice in obstructive hydrocephalus even in patients with former V-P shunt implantation. In case of acute or scheduled V-P shunt surgical revision, MRI is feasible, and if ventricular system obstruction is diagnosed, the hydrocephalus may be solved endoscopically.

  1. Imaging findings of arteriovenous malformations involving lung and liver in hereditary hemorrhagic telangiectasia(Osler-weber-rendu disease): two cases report

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Jeong Geun; Lee, Joo Hyuk; Seong, Su Ok [Cheongju St. Mary' s Hospital, Cheongju (Korea, Republic of)

    1999-09-01

    Hereditary hemorrhagic telangiectasia (HHT) or Osler-Weber-Rendu disease is an autosomal dominant disorder characterized by repeated episodes of bleeding. Multiple telangiectases consisting of thin-walled, dilated vascular channels with arteriovenous communication may involve, for example, mucocutaneous tissue, the gastrointestinal tract, and the liver, lung, and brain. We report the imaging findings of two cases of HHT involving arteriovenous malformation of both the lungs and liver, a rare condition. Chest radiography revealed a round mass, while helical CT showed a feeding artery and draining vein with arteriovenous malformation in the lung. Color Doppler sonography revealed an enlarged and tortuous hepatic artery with high systolic velocity. CT demonstrated an enlarged hepatic artery, arteriovenous shunt, and early draining hepatic vein in the liver. Celiac angiography showed arteriovenous malformation.

  2. An unusual case of fistula formation and thrombosis between arteriovenous graft and a native vein

    Directory of Open Access Journals (Sweden)

    Young Sub Kim

    2016-03-01

    Full Text Available Arteriovenous graft for hemodialysis vascular access is a widely used technique with many advantages. However, it has crucial complications with graft thrombosis and infection. We recently experienced an unusual case of arteriovenous graft complication involving graft thrombosis related to fistula formation between the graft and the natural vein with infection. We diagnosed this condition using Doppler ultrasound and computed tomography angiography. Successful surgical treatment including partial graft excision and creation of a secondary arteriovenous fistula using an inadvertently dilated cephalic vein was performed. The dialysis unit staff should keep this condition in mind and try to prevent this complication.

  3. Enhanced Piezoelectric Shunt Design

    Directory of Open Access Journals (Sweden)

    Chul H. Park

    2003-01-01

    Full Text Available Piezoceramic material connected to an electronic shunt branch circuit has formed a successful vibration reduction device. One drawback of the conventional electronic shunt circuit is the large inductance required when suppressing low frequency vibration modes. Also, the large internal resistance associated with this large inductance exceeds the optimal design resistance needed for low frequency vibration suppression. To solve this problem, a modified and enhanced piezoelectric shunt circuit is designed and analyzed by using mechanical-electrical analogies to present the physical interpretation. The enhanced shunt circuit developed in this paper is proved to significantly reduce the targeted vibration mode of a cantilever beam, theoretically and experimentally.

  4. Lumbar peritoneal shunt

    Directory of Open Access Journals (Sweden)

    Yadav Yad

    2010-01-01

    Full Text Available A lumbar peritoneal (LP shunt is a technique of cerebrospinal fluid (CSF diversion from the lumbar thecal sac to the peritoneal cavity. It is indicated under a large number of conditions such as communicating hydrocephalus, idiopathic intracranial hypertension, normal pressure hydrocephalus, spinal and cranial CSF leaks, pseudomeningoceles, slit ventricle syndrome, growing skull fractures which are difficult to treat by conventional methods (when dural defect extends deep in the cranial base or across venous sinuses and in recurrent cases after conventional surgery, raised intracranial pressure following chronic meningitis, persistent bulging of craniotomy site after operations for intracranial tumors or head trauma, syringomyelia and failed endoscopic third ventriculostomy with a patent stoma. In spite of the large number of indications of this shunt and being reasonably good, safe, and effective, very few reports about the LP shunt exist in the literature. This procedure did not get its due importance due to some initial negative reports. This review article is based on search on Google and PubMed. This article is aimed to review indications, complications, results, and comparison of the LP shunt with the commonly practiced ventriculoperitoneal (VP shunt. Shunt blocks, infections, CSF leaks, overdrainage and acquired Chiari malformation (ACM are some of the complications of the LP shunt. Early diagnosis of overdrainage complications and ACM as well as timely appropriate treatment especially by programmable shunts could decrease morbidity. Majority of recent reports suggest that a LP shunt is a better alternative to the VP shunt in communicating hydrocephalus. It has an advantage over the VP shunt of being completely extracranial and can be used under conditions other than hydrocephalus when the ventricles are normal sized or chinked. More publications are required to establish its usefulness in the treatment of wide variety of indications.

  5. Delayed otogenic pneumocephalus complicating ventriculoperitoneal shunt

    Directory of Open Access Journals (Sweden)

    Francesco Pieri

    2011-01-01

    Full Text Available Tension pneumocephalus complicating ventriculoperitoneal shunt is extremely rare. We report an elderly male who developed delayed tension pneumocephalus 12 months after ventriculoperitoneal shunt for hydrocephalus complicating aneurysmal subarachnoid hemorrhage. Fine-cut reformatted computer tomography scan revealed a large pneumatocele on the petrous apex associated with tegmen tympani defect. The shunt valve pressure was temporarily raised from 120 mm H 2 O to 200 mm H 2 O, and the patient underwent successful subtemporal extradural repair of the bony defect in the temporal bone. Although extremely rare, otogenic tension pneumocephalus is a potentially life-threatening condition, and urgent surgical repair of the bony defect in the temporal bone reduces the risk of both the morbidity and mortality.

  6. Distal splenorenal shunt with partial spleen resection

    Directory of Open Access Journals (Sweden)

    Gajin Predrag

    2007-01-01

    Full Text Available Introduction: Hypersplenism is a common complication of portal hypertension. Cytopenia in hypersplenism is predominantly caused by splenomegaly. Distal splenorenal shunt (Warren with partial spleen resection is an original surgical technique that regulates cytopenia by reduction of the enlarged spleen. Objective. The aim of our study was to present the advantages of distal splenorenal shunt (Warren with partial spleen resection comparing morbidity and mortality in a group of patients treated by distal splenorenal shunt with partial spleen resection with a group of patients treated only by a distal splenorenal shunt. Method. From 1995 to 2003, 41 patients with portal hypertension were surgically treated due to hypersplenism and oesophageal varices. The first group consisted of 20 patients (11 male, mean age 42.3 years who were treated by distal splenorenal shunt with partial spleen resection. The second group consisted of 21 patients (13 male, mean age 49.4 years that were treated by distal splenorenal shunt only. All patients underwent endoscopy and assessment of oesophageal varices. The size of the spleen was evaluated by ultrasound, CT or by scintigraphy. Angiography was performed in all patients. The platelet and white blood cell count and haemoglobin level were registered. Postoperatively, we noted blood transfusion, complications and total hospital stay. Follow-up period was 12 months, with first checkup after one month. Results In the first group, only one patient had splenomegaly postoperatively (5%, while in the second group there were 13 patients with splenomegaly (68%. Before surgery, the mean platelet count in the first group was 51.6±18.3x109/l, to 118.6±25.4x109/l postoperatively. The mean platelet count in the second group was 67.6±22.8x109/l, to 87.8±32.1x109/l postoperatively. Concerning postoperative splenomegaly, statistically significant difference was noted between the first and the second group (p<0.05. Comparing the

  7. Portasystemic shunt fraction quantification with colonic iodine-123 iodoamphetamine

    Energy Technology Data Exchange (ETDEWEB)

    Yen, C.K.; Pollycove, M.; Crass, R.; Lin, T.H.; Baldwin, R.; Lamb, J.

    1986-08-01

    Portasystemic shunting was quantified in dogs with (/sup 123/I)iodoamphetamine (IMP) administered transrectally into the colon and monitored externally with a gamma camera. IMP was absorbed rapidly and unchanged from the colon. After direct injection into the portal vein, IMP was almost completely extracted by the liver on the first pass, and the washout half-life was approximately 60 min. Based on these kinetic data, computer simulation of this biologic system was carried out. Errors associated with simplified models are calculated. The simplest model with insignificant error, which assumed that the tracer behaved like microspheres, was used to quantitate portasystemic shunt fraction in animals with surgically created shunts. Results were compared with the standard of /sup 99m/Tc-labeled macroaggregated albumin infused into a branch of inferior mesenteric vein. For shunt fractions ranging from 0 to 100%, an excellent correlation was seen, indicating that this approach is potentially a simple, noninvasive method of portasystemic shunt fraction quantification.

  8. A Rare Case of Acroangiodermatitis Associated with a Congenital Arteriovenous Malformation (Stewart-Bluefarb Syndrome) in a Young Veteran: Case Report and Review of the Literature.

    Science.gov (United States)

    Archie, Mark; Khademi, Saieh; Aungst, David; Nouvong, Aksone; Freeman, Shanna; Gelabert, Hugh; Rigberg, David; deVirgilio, Christian; Lewis, Michael; O'Connell, Jessica

    2015-10-01

    Acroangiodermatitis (AD) is a rare angioproliferative disease manifesting with cutaneous lesions clinically similar to Kaposi's sarcoma. AD is a benign hyperplasia of preexisting vasculature and may be associated with acquired or congenital arteriovenous malformations (AVM), or severe chronic venous insufficiency (because of hypostasis, elevated venous pressure, arteriovenous shunting). Stewart-Bluefarb syndrome is the rare syndrome in which AD is associated with a congenital AVM. We present the case of a young veteran with a painful, chronic nonhealing ulcer and ipsilateral popliteal artery occlusion likely because of trauma, who elected transmetatarsal amputation for symptomatic relief. A 24-year-old male veteran presented with a 5-year history of a nonhealing dorsal left foot ulcer, resulting from a training exercise injury. He ultimately developed osteomyelitis requiring antibiotics, frequent debridements, multiple trials of unsuccessful skin substitute grafting, and severe unremitting pain. He noted a remote history of left digital deformities treated surgically as a child, and an AVM, previously endovascularly treated at an outside facility. Arterial duplex revealed somewhat dampened left popliteal, posterior tibial (PT), and dorsalis pedis (DP) artery signals with arterial brachial index of 1.0. CT angiography showed occlusion of the proximal to mid popliteal artery with significant calcifications felt initially to be a result of prior trauma. Pedal pulses were palpable and transcutaneous oxygen measurements revealed adequate oxygenation. Because of unremitting pain, the patient opted for amputation. Pathology revealed vascular proliferation consistent with AD. This case illustrates an unusual diagnosis of acroangiodermatitis, and a rare syndrome when associated with his underlying AVM (Stewart-Bluefarb syndrome). This resulted in a painful, chronic ulcer and was further complicated by trauma-related arterial occlusive disease. AD disease can hinder wound

  9. Embryological Consideration of Dural Arteriovenous Fistulas

    Science.gov (United States)

    TANAKA, Michihiro

    2016-01-01

    The topographical distribution of dural arteriovenous fistulas (DAVFs) was analyzed based on the embryological anatomy of the dural membrane. Sixty-six consecutive cases of intracranial and spinal DAVFs were analyzed based on the angiography, and each shunt point was identified according to the embryological bony structures. The area of dural membranes was categorized into three different groups: a ventral group located on the endochondral bone (VE group), a dorsal group located on the membranous bone (DM group) and a falcotentorial group (FT group) located in the falx cerebri, tentorium cerebelli, falx cerebelli, and diaphragm sellae. The FT group was designated when the dural membrane was formed only with the dura propria (meningeal layer of the dura mater) and not from the endosteal dura. Cavernous sinus, sigmoid sinus, and anterior condylar confluence was categorized to VE group, which had a female predominance, more benign clinical presentations, and a lower rate of cortical and spinal venous reflux. Transverse sinus, confluence, and superior sagittal sinus belonged to the DM group. Olfactory groove, falx, tent of the cerebellum, and nerve sleeve of spinal cord were categorized to the FT group, which presented later in life and which had a male predominance, more aggressive clinical presentations, and significant cortical and spinal venous reflux. The DAVFs was associated with the layers of the dural membrane characterized by the two different embryological bony structures. The FT group was formed only with the dura propria as an independent risk factor for aggressive clinical course and hemorrhage of DAVFs. PMID:27250699

  10. Pulmonary arteriovenous malformation in cryptogenic liver cirrhosis.

    Science.gov (United States)

    Afzal, Noureen; Akhtar, Saleem; Ahmed, Shakeel; Atiq, Mehnaz

    2013-09-01

    The cause in 10 - 20% cases of liver cirrhosis (LC) cannot be elucidated, and are thus termed cryptogenic. Pulmonary arteriovenous malformations (PAVMs) are relatively rare, but the most common anomaly involving the pulmonary tree. Although the rare correlation between LC and PAVM is well-known, there have been no reports of PAVMs occurring in cryptogenic LC. We report a case of PAVM that occurred in cryptogenic liver cirrhosis in a 3 years old male child. The child presented with complaints of malena, hematemesis and variceal bleed. The examination revealed a child with respiratory distress, irritability, tachycardia, clubbing and abdominal distention. He was worked up for recurrent variceal bleeding secondary to portal hypertension but the oxygen saturation during hospital stay kept deteriorating. The diagnosis of hepatopulmonary syndrome as the cause of persistent hypoxemia in the absence of other cardio-pulmonary causes was then made by enhanced echocardiogram using agitated saline. He improved significantly after liver transplantation performed abroad. At a 6 months follow-up, the child was stable with no evidence of intrapulmonary shunting on repeat echo.

  11. Giant Arteriovenous Malformation of the Neck

    Directory of Open Access Journals (Sweden)

    P. A. Dieng

    2015-01-01

    Full Text Available Arteriovenous malformations (AVM have a wide range of clinical presentations. Operative bleeding is one of the most hazardous complications in the surgical management of high-flow vascular malformations. In the cervical region, the presence of vital vascular structures, such as the carotid artery and jugular vein, may increase this risk. This is a case of massive arteriovenous malformation deforming the neck and the face aspect of this aged lady and growing for several years. A giant mass of the left neck occupied the carotid region and the subclavian region. The AVM was developed between the carotid arteries, jugular veins, and vertebral and subclavian vessels, with arterial and venous flux. The patient underwent surgery twice for the cure of that AVM. The first step was the ligation of the external carotid. Seven days later, the excision of the mass was done. In postoperative period the patient presented a peripheral facial paralysis which completely decreased within 10 days. The first ligation of the external carotid reduces significantly the blood flow into the AVM. It permitted secondarily the complete ablation of the AVM without major bleeding even though multiple ligations were done.

  12. Hemodynamics of patient-specific aorta-pulmonary shunt configurations

    OpenAIRE

    Pekkan, Kerem; Pişkin, Senol; Altın, H. Fırat; Yıldız, Okan; Bakır, İhsan

    2017-01-01

    Optimal hemodynamics in aorta-pulmonary shunt reconstruction is essential for improved post-operative recovery of the newborn congenital heart disease patient. However, prior to in vivo execution, the prediction of post-operative hemodynamics is extremely challenging due to the interplay of multiple confounding physiological factors. It is hypothesized that the post-operative performance of the surgical shunt can be predicted through computational blood flow simulations that consider patient ...

  13. Hydrocephalus and Shunts

    Science.gov (United States)

    SBA National Resource Center: 800-621-3141 Hydrocephalus and Shunts Approximately 80% of people with SB have Hydrocephalus Hydrocephalus means there is a build-up of cerebrospinal also called CSF, around ...

  14. Distal splenorenal shunt

    Science.gov (United States)

    ... path. As a result, swollen blood vessels called varices form. They develop thin walls that can break ... or x-rays show that you have bleeding varices. Distal splenorenal shunt surgery reduces pressure on the ...

  15. Congenital extrahepatic portosystemic shunt associated with heterotaxy and polysplenia

    Energy Technology Data Exchange (ETDEWEB)

    Newman, Beverley [Lucile Packard Children' s Hospital, Department of Radiology, Stanford University School of Medicine, Stanford, CA (United States); Feinstein, Jeffrey A. [Stanford University School of Medicine, Division of Pediatric Cardiology, Department of Pediatrics, Lucile Packard Children' s Hospital, Stanford (United States); Cohen, Ronald A.; Patel, Hitendra [Children' s Hospital and Research Center, Department of Diagnostic Radiology, Oakland, CA (United States); Feingold, Brian; Kreutzer, Jacqueline [Children' s Hospital of Pittsburgh, Department of Pediatrics, Division of Pediatric Cardiology, Pittsburgh, PA (United States); Chan, Fandics P. [Stanford University School of Medicine, Cardiovascular Imaging Section, Department of Radiology, Lucile Packard Children' s Hospital, Stanford, CA (United States)

    2010-07-15

    Heterotaxy with polysplenia is associated with many cardiovascular anomalies including the occasional occurrence of congenital extrahepatic portosystemic shunts (CEPS). Missing this anomaly can lead to inappropriate and ineffective therapy. To emphasize the importance and associated anatomy of CEPS in conjunction with heterotaxy with polysplenia. Review of three young children who presented with cyanosis and pulmonary hypertension without a cardiac etiology. They were known (1) or discovered (2) to have heterotaxy with polysplenia. There was absence of the intrahepatic inferior vena cava (IVC) with azygos or hemiazygos continuation in all three cases. In spite of normal liver function, they were discovered to have large portosystemic shunts, splenorenal in location, along with diffuse peripheral pulmonary arterial dilatation suggestive of CEPS (Abernethy malformation) with hepatopulmonary or, more accurately, portopulmonary syndrome. All CEPS were ipsilateral to the spleens. Patency of the portal veins in these cases allowed for percutaneous shunt closure with resolution of cyanosis. CEPS is associated with heterotaxy with polysplenia and can be symptomatic because of pulmonary arteriovenous (AV) shunting. Portal and hepatic vein patency are critical for determining feasibility of CEPS closure. (orig.)

  16. Vascular access for hemodialysis: arteriovenous fistula.

    Science.gov (United States)

    Malovrh, Marko

    2005-06-01

    The long-term survival and quality of life of patients on hemodialysis (HD) is dependant on the adequacy of dialysis via an appropriately placed vascular access. The optimal vascular access is unquestionably the autologous arteriovenous fistula (AVF), with the most common method being the conventional radio-cephalic fistula at the wrist. Recent clinical practice guidelines recommend the creation of native fistula or synthetic graft before the start of chronic HD therapy to prevent the need for complication-prone dialysis catheters. This could also have a beneficial effect on the rapidity of worsening kidney failure. A multidisciplinary approach (nephrologists, surgeons, radiologists and nurses) should improve the HD outcome by promoting the use of AVF. An important additional component of this program is the Doppler ultrasound for preoperative vascular mapping. Such an approach may be realized without unsuccessful surgical explorations, with a minimal early failure rate and a high maturation, even in patients with diabetes mellitus.

  17. Vascular collateralization along ventriculoperitoneal shunt catheters in moyamoya disease.

    Science.gov (United States)

    Singla, Amit; Lin, Ning; Ho, Allen L; Scott, R Michael; Smith, Edward R

    2013-06-01

    Surgically created openings such as bur holes can serve as avenues for the development of collateral blood supply to the brain in patients with moyamoya disease. When such collateralization occurs through preexisting shunt catheter sites, the potential exists for perioperative stroke if these vessels are damaged during revision of a ventricular catheter for shunt malfunction. In this paper the authors report on a series of patients with a history of ventriculoperitoneal (VP) shunts who later developed moyamoya disease and were found to have spontaneous transdural collateral vessels at ventricular catheter sites readily visualized on diagnostic angiography. A consecutive surgical series of 412 patients with moyamoya disease treated at Boston Children's Hospital from 1990 to 2010 were reviewed to identify patients with concomitant moyamoya and a VP shunt. The clinical records and angiograms of these patients were reviewed to determine the extent of bur hole collaterals through the shunt site. Three patients were identified who had VP shunts placed for hydrocephalus and subsequently developed moyamoya disease. All 3 patients demonstrated spontaneous transdural collaterals at the ventricular catheter bur hole, as confirmed by angiography during the workup for moyamoya disease. No patients required subsequent revision of their ventricular catheters following the diagnosis of moyamoya. All patients have remained stroke free and clinically stable following pial synangiosis. Although the association of moyamoya and shunted hydrocephalus is rare, it may present a significant potential problem for the neurosurgeon treating a shunt malfunction in this patient population, because shunt bur holes may become entry sites for the ingrowth of significant cortical transdural collateral blood supply to the underlying brain. Shunt revision might therefore be associated with an increased risk of postoperative stroke or operative-site hemorrhage in this population if this

  18. Local Model of Arteriovenous Malformation of the Human Brain

    Science.gov (United States)

    Nadezhda Telegina, Ms; Aleksandr Chupakhin, Mr; Aleksandr Cherevko, Mr

    2013-02-01

    Vascular diseases of the human brain are one of the reasons of deaths and people's incapacitation not only in Russia, but also in the world. The danger of an arteriovenous malformation (AVM) is in premature rupture of pathological vessels of an AVM which may cause haemorrhage. Long-term prognosis without surgical treatment is unfavorable. The reduced impact method of AVM treatment is embolization of a malformation which often results in complete obliteration of an AVM. Pre-surgical mathematical modeling of an arteriovenous malformation can help surgeons with an optimal sequence of the operation. During investigations, the simple mathematical model of arteriovenous malformation is developed and calculated, and stationary and non-stationary processes of its embolization are considered. Various sequences of embolization of a malformation are also considered. Calculations were done with approximate steady flow on the basis of balanced equations derived from conservation laws. Depending on pressure difference, a fistula-type AVM should be embolized at first, and then small racemose AVMs are embolized. Obtained results are in good correspondence with neurosurgical AVM practice.

  19. Pathophysiology of shunt dysfunction in shunt treated hydrocephalus

    DEFF Research Database (Denmark)

    Blegvad, C.; Skjolding, A D; Broholm, H

    2013-01-01

    We hypothesized that shunt dysfunction in the ventricular catheter and the shunt valve is caused by different cellular responses. We also hypothesized that the cellular responses depend on different pathophysiological mechanisms....

  20. Hydrocephalus in a patient with an unruptured pial arteriovenous fistula: hydrodynamic considerations, endovascular treatment, and clinical course.

    Science.gov (United States)

    Morales-Gómez, Jesús A; Garza-Oyervides, Vicente V; Arenas-Ruiz, José A; Mercado-Flores, Mariana; Elizondo-Riojas, C Guillermo; Boop, Frederick A; de León, Ángel Martínez-Ponce

    2017-03-01

    Intracranial pial arteriovenous fistulas, also known as nongalenic fistulas, are rare vascular malformations affecting predominantly the pediatric population. Hydrocephalus is an unusual presentation in which the exact pathophysiology is not fully understood. The aim of treatment in these cases is occlusion of the fistula prior to considering ventricular shunting. Here, the authors describe the hydrodynamic considerations of the paravascular pathway and the resolution of hydrocephalus with endovascular treatment of the fistula.

  1. A tiny dural arteriovenous fistula

    Institute of Scientific and Technical Information of China (English)

    ZHANG Peng 张 鹏; ZHU Fengshui 朱风水; LING Feng 凌 锋; Christophe COGNARD

    2003-01-01

    @@ Pulsatile tinnitus is commonly encountered in approximately 10% of a given population.1 Since causes of the disease vary, selecting appropriate protocols of imaging strategies is quite challenging.2 Vascular anormalies or diseases including anormalies of the carotid arteries and jugular veins, intracranial arteriovenous malformation and dural arteriovenous fistula (DAVF) are major causative factors of the disease. Before imaging studies, history inquiry and physical examination are important for detect the possible causes of pulsatile tinnitus. Different imaging examinations are depended on histories and clinical signs of different patients.

  2. Arteriovenous Malformation of the Pancreas

    Directory of Open Access Journals (Sweden)

    Alexandros Charalabopoulos

    2011-01-01

    Full Text Available Pancreatic arteriovenous malformation (PAVM is a very rare and mostly congenital lesion, with less than 80 cases described in the English-published literature. It is defined as a tumorous vascular abnormality that is constructed between an anomalous bypass anastomosis of the arterial and venous networks within the pancreas. It represents about 5% of all arteriovenous malformations found in the gastrointestinal tract. Herein, we present a 64-year-old patient with symptomatic PAVM involving the body and tail of the organ, which was successfully treated by transcatheter arterial embolization. The disease spectrum and review of the literature are also presented.

  3. Dural arteriovenous fistulae after forehead knife-cut injury

    Institute of Scientific and Technical Information of China (English)

    朱刚; 陈志; 冯华

    2004-01-01

    @@ Dural arteriovenous fistulae (DAVF) is a rare intracranial vascular disease. It is pathologically characterized by direct shunting of the intracranial artery and vein, which results in cerebral ischemia, intracranial hemorrhage, neural deficit and intracranial murmur. The etiological mechanism of DAVF is not well known, but most researchers think it is associated with congenital abnormal development, especially abnormal development of dural blood vessels at the stage of embryogenesis. Recently, some researchers have found that DAVF is also associated with some acquired factors. This article reports a case who developed DAVF within 2 years after debridement of frontal bone fragmentation, depressed fracture, left frontal lobe contusion and superior sagittal sinus injury due to forehead knife-cut injury. The pathogenic mechanism was explored through a review of the related literatures.

  4. Acquired arteriovenous fistula in a grizzly bear (Ursus arctos horribilis).

    Science.gov (United States)

    Tuttle, Allison D; MacLean, Robert A; Linder, Keith; Cullen, John M; Wolfe, Barbara A; Loomis, Michael

    2009-03-01

    A captive adult male grizzly bear (Ursus arctos horribilis) was evaluated due to multifocal wounds of the skin and subcutaneous tissues sustained as a result of trauma from another grizzly bear. On presentation, one lesion that was located in the perineal region seemed to be a deep puncture with purple tissue protruding from it. This perineal wound did not heal in the same manner or rate as did the other wounds. Twenty-five days after initial detection, substantial active hemorrhage from the lesion occurred and necessitated anesthesia for examination of the bear. The entire lesion was surgically excised, which later proved curative. An acquired arteriovenous fistula was diagnosed via histopathology. Arteriovenous fistulas can develop after traumatic injury and should be considered as a potential complication in bears with nonhealing wounds.

  5. Congenital arteriovenous fistula of the horseshoe kidney with multiple hemangiomas

    Directory of Open Access Journals (Sweden)

    Lazić Miodrag

    2012-01-01

    Full Text Available Introduction. Congenital renal arteriovenous fistulas (AVF are rare, especially if they are associated with other developmental renal anomalies. Case Outline. A 34-year-old female was hospitalized due to total painless hematuria and bladder tamponade. Excretory urography revealed a horseshoe kidney with normal morphology of pyelocaliceal system and ureters. Aortography and selective renovasography detected a cluster-like vascular formation with multiple arteriovenous fistulas (AVF. Due to a large AVF gauge and poor flow of the efferent vein to the inferior vena cava, a surgical procedure of two renal artery segmentary branches ligation and division was performed. During the operative procedure, the presence of multiple superficial renal hemangiomas was detected. Conclusion. Although selective arterial embolization represents the preferable treatment option, conventional surgery remains favorable alternative in selected cases with large and complex AVF.

  6. Linear accelerator radiosurgery for arteriovenous malformations: Updated literature review.

    Science.gov (United States)

    Yahya, S; Heyes, G; Nightingale, P; Lamin, S; Chavda, S; Geh, I; Spooner, D; Cruickshank, G; Sanghera, P

    2017-04-01

    Arteriovenous malformations (AVMs) are the leading causing of intra-cerebral haemorrhage. Stereotactic radiosurgery (SRS) is an established treatment for arteriovenous malformations (AVM) and commonly delivered using Gamma Knife within dedicated radiosurgery units. Linear accelerator (LINAC) SRS is increasingly available however debate remains over whether it offers an equivalent outcome. The aim of this project is to evaluate the outcomes using LINAC SRS for AVMs used within a UK neurosciences unit and review the literature to aid decision making across various SRS platforms. Results have shown comparability across platforms and strongly supports that an adapted LINAC based SRS facility within a dynamic regional neuro-oncology department delivers similar outcomes (in terms of obliteration and toxicity) to any other dedicated radio-surgical platform. Locally available facilities can facilitate discussion between options however throughput will inevitably be lower than centrally based dedicated national radiosurgery units.

  7. The hydrokinetic parameters of shunts for hydrocephalus might be inadequate.

    Science.gov (United States)

    Sotelo, Julio

    2012-01-01

    Long-term treatment of hydrocephalus continues to be dismal. Shunting is the neurosurgical procedure more frequently associated with complications, which are mostly related with dysfunctions of the shunting device, rather than to mishaps of the rather simple surgical procedure. Overdrainage and underdrainage are the most common dysfunctions; of them, overdrainage is a conspicuous companion of most devices. Even when literally hundreds of different models have been proposed, developed, and tested, overdrainage has plagued all shunts for the last 60 years. Several investigations have demonstrated that changes in the posture of the subject induce unavoidable and drastic differences of intraventricular hydrokinetic pressure and cerebrospinal fluid (CSF) drainage through the shunt. Of all the parameters that participate in the pathophysiology of hydrocephalus, the only invariable one is cerebrospinal fluid production at a constant rate of approximately 0.35 ml/min. However, this feature has not been considered in the design of currently available shunts. Our experimental and clinical studies have shown that a simple shunt, whose drainage capacity complies with this unique parameter, would prevent most complications of shunting for hydrocephalus.

  8. residue and shunting pinholes

    Science.gov (United States)

    Gorji, Nima E.

    2014-09-01

    The present work considers two observable phenomena through the experimental fabrication and electrical characterization of the rf-sputtered CdS/CdTe thin film solar cells that extremely reduce the overall conversion efficiency of the device: CdCl2 residue on the surface of the semiconductor and shunting pinholes. The former happens through nonuniform treatment of the As-deposited solar cells before annealing at high temperature and the latter occurs by shunting pinholes when the cell surface is shunted by defects, wire-like pathways or scratches on the metallic back contact caused from the external contacts. Such physical problems may be quite common in the experimental activities and reduce the performance down to 4-5 % which leads to dismantle the device despite its precise fabrication. We present our electrical characterization on the samples that received wet CdCl2 surface treatment (uniform or nonuniform) and are damaged by the pinholes.

  9. Treatment of postcatheterization femoral arteriovenous fistulas with simple prolonged bandaging

    Institute of Scientific and Technical Information of China (English)

    ZHOU Tao; LIU Zhen-jiang; ZHOU Sheng-hua; SHEN Xiang-qian; LIU Qi-ming; FANG Zhen-fei; HU Xin-qun; LI Jiang; L(U) Xiao-lin

    2007-01-01

    Background The methods for the treatment of postcatheterization femoral arteriovenous fistulas (AVF-s) - simple observation, ultrasound guided compression, covered stents implantation and coil embolization have poor outcome.Surgery is the standard method for treatment of femoral AVFs, but it is a traumatic operation. In this study, we report the results of the treatment of postcatheterization femoral AVFs by simple prolonged compressing bandage.Methods To treat iatrogenic femoral AVFs caused by transfemoral catheterization, prolonged binding with elastic or common bandage was applied in 16 cases. Catheterization was performed in 7 cases for radiofrequency current catheter ablation, in 4 for occlusion of congenital heart disease, in 3 for percutaneous coronary intervention, in 1 for coronary angiography and in 1 for right heart catheterization.Results All iatrogenic femoral AVFs were healed after simple binding with elastic or common bandage for 4-46 days (mean (15±10) days). During the period of binding, local skins ulceration occurred at puncture site in two cases and femoral vein thrombus was found in one patient. During 6-24 months (mean (11.8±3.6) months) followup with colour Doppler ultrasonography, no recurrent arteriovenous shunting or other complications were observed.Conclusion The results suggest that simple prolonged bandaging for postcatheterization femoral AVFs is an effective and economical procedure.

  10. Cervical Myelopathy Caused by Intracranial Dural Arteriovenous Fistula

    Science.gov (United States)

    Kim, Won Young; Kim, Jin Bum; Nam, Taek Kyun; Kim, Young Baeg

    2016-01-01

    Intracranial dural arteriovenous fistula (dAVF) usually results in various problems in the brain. But it can be presented as a myelopathy, which may make early diagnosis and management to be difficult. We recently experienced a case of cervical myelopathy caused by intracranial dAVF. A 60-year-old man presented with a 3-year history of gait disturbance due to a progressive weakness of both legs. Neurological examination revealed spastic paraparesis (grade IV) and Babinski sign on both sides. Magnetic resonance imaging showed serpentine vascular signal voids at C2-T1 on T2-weighted image with increased signal intensity and swelling of spinal cord at C1-C4. We performed a brain computed tomography angiography and found intracranial dAVF with multiple arteriovenous shunts. Venous drainages were noted at tentorial veins and cervical perimedullary veins. After Onyx embolization, the patient showed gradual improvement in motor power and gait disturbance. The venous drainage pattern is a well-known prognostic factor of dAVF. In our case, the intracranial dAVF drained to spinal perimedullary vein, which seemed to result in the ischemic myelopathy. Although it is rare condition, it sometimes can cause serious complications. Therefore, we should keep in mind the possibility of intracranial dAVF when a patient presents myelopathy. PMID:27437016

  11. Arteriovenous Patterns in Beaked Whales

    Science.gov (United States)

    2015-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Arteriovenous patterns in beaked whales Alexander M...from which future morphological (e.g. acoustic pathways), pathophysiological (e.g. decompression sickness and embolus formation) and mathematical...extramandibular fat body (EMFB), intramandibular fat body (IMFB) and pterygoid venous lake. 2) To describe the vascular morphology of the pulmonary system

  12. [Arterial steal via an arteriovenous fistula for hemodialysis. A clinical case and review of the literature].

    Science.gov (United States)

    Juliá Montoya, J; Lozano Vilardell, P; Corominas Roura, C; Blanes Mompó, I; Flores López, D; Manuel-Rimbau Muñoz, E; García de la Torre, A

    1993-01-01

    We related a case of arterial atrappment in the left upper limb by an arteriovenous humerus-cephalic hyperfunctioning fistula. Surgical procedure consisted on the insertion of a PTFE's banding around the arterialized vein obtaining satisfactory clinic and functional results. We review in the literature, the frequency the pathogeny and the therapeutics possibilities.

  13. Coexistence of a single cerebral arteriovenous malformation and spinal arteriovenous malformation

    Directory of Open Access Journals (Sweden)

    Wang Yabing

    2009-01-01

    Full Text Available The coexistence of a cerebral and a spinal arteriovenous malformation (AVM together is extremely rare. We present a 31-year-old woman, who suffered from severe root pains in the left upper extremity. Magnetic resonance imaging (MRI revealed the abnormal vessels in the left occipital lobe and upper cervical segment of spinal cord. Cerebral angiography and spinal angiogram revealed two AVMs: One was in the right occipital lobe and the other was located in the C1-C2 segments of cervical cord. She had no other vascular lesions, and nor did her other family members. As the primary problem in her was left upper extremity root pains, which we considered was related to the spinal AVM, the first therapeutic treatment was focused on spinal AVM. The cerebral AVM of the right occipital lobe was surgically resected after part embolization.

  14. Penile Gangrene with Abscess Formation after Modified Al-Ghorab Shunt for Idiopathic Ischemic Priapism

    Directory of Open Access Journals (Sweden)

    Beneranda S. Ford-Glanton

    2014-01-01

    Full Text Available Penile gangrene is a rare but unfortunate complication of surgical intervention and priapism shunts. The literature regarding penile gangrene following surgical correction of priapism is sparse, the majority of which dates back to thirty to forty years. Here, we present the case of a 60-year-old man who presented with priapism that required operative management with a modified Al-Ghorab shunt and eventually suffered from complete necrosis of the penis with abscess formation in both corpora cavernosa.

  15. [Arteriovenous fistulae of posttraumatic origin: apropos 7 cases].

    Science.gov (United States)

    Lerma, R; Galego, G; Lisbona, C; Martorell, A; Silveira, P; Callejas, J M

    1992-01-01

    We present our experience with arterio-venous traumatic fistulas. Seven cases, between 6 patients are reviewed. Respective etiologies were: 4 cases after an accidental traumatism, 2 cases produced by iatrogenicity and 1 case of idiopathic etiology. Respective localizations were: 6 cases at lower limbs (85.7%) and one case at cervical column (14.2%). All patients underwent surgical treatment. There was any case of mortality and treatment results were satisfactory in all cases. Patients were followed and, up to now, no recidives have been registered. follow-time ranged from 1.5 to more than 6 years.

  16. Evaluation of left-to-right shunts in adults with atrial septal defect using first-pass radionuclide cardiography

    DEFF Research Database (Denmark)

    Kelbaek, H; Aldershvile, J; Svendsen, Jesper Hastrup;

    1992-01-01

    outputs of the right and left ventricle was 0.04 l.min-1, the limits of agreement -0.80 to 0.88 l.min-1 and the 95% confidence interval for the bias -0.14 to 0.22 l.min-1. Right-sided cardiac catheterization was performed to assess the severity of the arterio-venous shunt by oximetry in 18 adult patients...

  17. Reducing CSF shunt placement in patients with spinal myelomeningocele

    Directory of Open Access Journals (Sweden)

    Suresh Sankhla

    2009-01-01

    Full Text Available Object: The incidence of hydrocephalus requiring shunts in children with myelomeningocele (MMC is reported to be very high. Shunt-related complications are a significant cause of morbidity and mortality in this population. In order to minimize shunt placements, we used very rigid clinical selection criteria and followed them in all patients who had myelomeningocele and enlarged ventricles. The follow-up outcome of this retrospective study is reported. Methods: From 2000 to 2007, 23 patients with myelomeningocele and variable degree of hydrocephalus were treated at our institute with primary surgical closure of their myelomeningoceles without a CSF diversion procedure. Patients with severe hydrocephalus who required immediate shunt insertion, and those with no significant associated hydrocephalus were not included in this study. Data regarding the surgical results and complications, postoperative management, and the outcome at follow-up were obtained from their hospital records. Results: Initially increased size of the ventricular system was found to have decreased or stabilized in 17 (81% patients postoperatively. However, ventriculomegaly continued to progress further in 4 (19% out of 21 patients. Of 11 patients who presented with enlarged head, eight (73% patients showed reduction or stabilization in their head circumference. Three (27% children continued to have progressive head enlargement in the postoperative period and required shunt placement. Signs of raised intracranial pressure observed in six patients on admission, improved in two (33% and persisted or worsened in four (67% patients who eventually improved after the insertion of a shunt. Eight (35% patients experienced wound-related complications following closure of the MMC, including CSF leak in four, wound infection in three, wound breakdown in three, and pseudomeningocele in two patients. Shunt placement was required in the postoperative period in 13 (56.5% patients to treat

  18. 脑动静脉畸形破裂出血并脑疝的急诊手术治疗%Emergent Surgical Treatment of Acute Hemorrhagic Intracranial Arteriovenous Malformation with Intracerebral Herniation

    Institute of Scientific and Technical Information of China (English)

    魏健; 刘维生; 王永和; 曹培成; 卜振富

    2013-01-01

      目的探讨脑动静脉畸形(AVMs)破裂出血并脑疝的急诊手术问题。方法回顾性分析我院17例AVMs急性破裂出血合并脑疝并行急诊手术治疗的病例资料。结果患者术后半年GOS评定疗效,良好4例,中残6例,重残2例,植物生存2例,死亡3例。术后并发肺部感染4例,皮瓣下积液2例,颅内感染并脑积水1例,迟发血肿1例。结论急诊手术治疗是AVMs破裂出血并脑疝首选治疗方法,能够提高病人生存率,降低致残率。%Objective To study the emergent operative treatment of acute hemorrhagic cerebral arteriove-nous malformations(AVMs) with cerebral herniation.Methods A retrospective analysis of 17 patients with acute hemor-rhagic cerebral AVMs with cerebral herniation was carried out ,who were treated with emergent operative treatment .Re-sults According to GOS scale six month after operation ,4 patients recovered well,moderately disabled in 6 cases,se-verely disabled in 2 cases,vegetably survived in 2 cases,3 patients died after operation,4 cases with pneumonia after op-eration,2 cases with subdural hydroma ,1 case with intracranial infection and hydrocephalus ,1 case with recurrent hema-toma.Conclusion The emergent hematoma debridement and AVMs excision by microneurosurgery is the optimal effec-tive method to treat AVMs with cerebral herniation because it can heighten survival rate and decrease disability rate .

  19. 双血管融合技术在硬脑膜动静瘘诊断和手术计划中的应用%Application of dual vessel fusion technique in the diagnosis of dural arteriovenous fistula and surgical planning

    Institute of Scientific and Technical Information of China (English)

    盛柳青; 李俊; 李国栋; 李欢欢; 陈刚; 向伟楚; 王强; 甘志强; 马廉亭

    2015-01-01

    Objective To investigate the application values of dual vessel fusion technique in the diagnosis of dural arteriovenous fistula (DAVF) and surgical planning.Methods Ten patients with DAVF underwent selective cerebral angiography using plate digital subtraction angiography (DSA).The lesion vessels performed three-dimensional angiography.The "double volume reconstruction" technique was used to perform two-vessel three-dimensional image fusion at the three-dimensional workstation.The angioarchitecture of DAVF was investigated.Results Ten patients obtained satisfactory "dual vessel fusion" with a good spatial coherence.On the dual vessel fusion images,the blood flow from different feeding arteries flowed together into the same fistula and draining vein (presented as a fusion of red and white blood flow) and the location and shape of the fistula cold be identified clearly.It could be used to guide the choice of treatment strategy,design surgery and surgical intervention plan.Conclusions Based on the "dual vessel fusion" of fiat panel DSA three-dimensional vascular data,it can obtain accurate vascular fusion,more clearly reveal fistulas,feeding arteries,draining veins and other angioarchitecture information of DAVF,and ultimately be beneficial to the development of surgical planning.%目的 探讨双血管融合技术在硬脑膜动静瘘(dural arteriovenous fistula,DAVF)诊断和手术计划中的应用价值,指导术中准确找到瘘口.方法 在10例DAVF病例采用平板DSA行选择性全脑血管造影,病变血管行三维血管成像.在三维工作站采用“双容积重建”技术进行两支血管三维像的融合,研究DAVF的血管构筑.结果 在10例均获得满意的“双血管融合”,具有很好的空间一致性.在双血管融合图像上可以清晰看到来自不同供血动脉的血流汇流到同一瘘口和引流静脉(表现为红白相间的血流融合),可以清晰判断瘘口的部位和形态,指导选择治疗策略、设计外

  20. Creation of transcatheter aortopulmonary and cavopulmonary shunts using magnetic catheters: feasibility study in swine.

    Science.gov (United States)

    Levi, Daniel S; Danon, Saar; Gordon, Brent; Virdone, Nicky; Vinuela, Fernando; Shah, Sanjay; Carman, Greg; Moore, John W

    2009-05-01

    Surgical shunts are the basic form of palliation for many types of congenital heart disease. The Glenn shunt (superior cavopulmonary connection) and central shunt (aortopulmonary connection) represent surgical interventions that could potentially be accomplished by transcatheter techniques. We sought to investigate the efficacy of using neodymium iron boron (NdFeB) magnetic catheters to create transcatheter cavopulmonary and aortopulmonary shunts. NdFeB magnets were machined and integrated into catheters. "Target" catheters were placed in the pulmonary arteries (PAs), and radiofrequency "perforation" catheters were placed in either the descending aorta (DAo) for central shunts or the superior vena cava (SVC) for Glenn shunts. The magnet technique or "balloon target" method was used to pass wires from the DAo or the SVC into the PA. Aortopulmonary and cavopulmonary connections were then created using Atrium iCAST covered stents. Magnet catheters were used to perforate the left pulmonary artery from the DAo, thereby establishing a transcatheter central shunt. Given the orientation of the vasculature, magnetic catheters could not be used for SVC-to-PA connections; however, perforation from the SVC to the right pulmonary artery was accomplished with a trans-septal needle and balloon target. Transcatheter Glenn or central shunts were successfully created in four swine.

  1. Rare malformation of glans penis: arteriovenous malformation.

    Science.gov (United States)

    Akin, Y; Sarac, M; Yucel, S

    2013-01-01

    Pediatric glans penis malformations, especially arteriovenous malformations (AVM), are very rare. Herein, we report two rare cases. A 14-year-old boy attended our outpatient clinic with chief complaints of purple swelling and rapidly growing lesion on the glans penis. The lesion was excised surgically after physical and radiological evaluations. Pathology reported AVM and the patient is being followed up. The second case is a 2-year-old boy who was admitted with a big lesion involving glans penis and genital area that has been present since birth. In physical and radiological evaluations, lesion on the glans penis was pulsatile. Parents of the patient did not want any surgery and patient has been in follow-up. Diagnosis of the vascular lesions on glans penis is very easy by physical and radiological examinations today. Long-term follow-up is very important for AVM. Clinicians must make a careful effort to document new glans lesions in the pediatric population and decrease anxiety in the parents of affected children.

  2. Controversies: Optic nerve sheath fenestration versus shunt placement for the treatment of idiopathic intracranial hypertension

    Directory of Open Access Journals (Sweden)

    Arielle Spitze

    2014-01-01

    Full Text Available Background: Idiopathic intracranial hypertension (IIH has been increasing in prevalence in the past decade, following the obesity epidemic. When medical treatment fails, surgical treatment options must be considered. However, controversy remains as to which surgical procedure is the preferred surgical option - optic nerve sheath fenestration (ONSF or cerebrospinal fluid (CSF shunting - for the long-term treatment of this syndrome. Purpose: To provide a clinical update of the pros and cons of ONSF versus shunt placement for the treatment of IIH. Design: This was a retrospective review of the current literature in the English language indexed in PubMed. Methods: The authors conducted a PubMed search using the following terms: Idiopathic IIH, pseudotumor cerebri, ONSF, CSF shunts, vetriculo-peritoneal shunting, and lumbo-peritoneal shunting. The authors included pertinent and significant original articles, review articles, and case reports, which revealed the new aspects and updates in these topics. Results: The treatment of IIH remains controversial and lacks randomized controlled clinical trial data. Treatment of IIH rests with the determination of the severity of IIH-related visual loss and headache. Conclusion: The decision for ONSF versus shunting is somewhat institution and surgeon dependent. ONSF is preferred for patients with visual symptoms whereas shunting is reserved for patients with headache. There are positive and negative aspects of both procedures, and a prospective, randomized, controlled trial is needed (currently underway. This article will hopefully be helpful in allowing the reader to make a more informed decision until that time.

  3. CSF hydrothorax without intrathoracic catheter migration in children with ventriculoperitoneal shunt

    Directory of Open Access Journals (Sweden)

    Joon-Hyung Kim

    2015-01-01

    Full Text Available Background: Thoracic complications of ventriculoperitoneal (VP shunts have been extensively reported in the literature. Cerebrospinal fluid (CSF hydrothorax without catheter migration, however, has been rarely described and poorly understood. Case Description: We describe development of pleural effusion and respiratory distress in a 3-year-old boy with no evidence of VP shunt catheter displacement on plain radiograph and stable ventricle size on rapid sequence magnetic resonance imaging (MRI brain. Chest X-ray revealed complete opacity of right hemithorax. Pleural effusion was consistent with transudate. Beta-2 transferrin returned positive. The patient underwent externalization of VP shunt, and upon resolution of effusion, re-internalization with new distal shunt catheter. A literature review of CSF hydrothorax in children without intrathoracic shunt migration was performed. Eleven cases were identified in the English literature. Age at VP shunt placement ranged from birth to 8 years of age. Interval from VP shunt placement to CSF hydrothorax ranged from 1.5 months to 5 years. History of shunt revision was reported in two cases. Presenting symptoms also included ascites and inguinal hernia or hydrocele. Reported diagnostic studies consist of CSF culture, radionuclide shuntogram, beta-2 transferrin, and beta-trace protein. Laterality of the VP shunt and development of pleural effusion were predominantly right sided. Definitive surgical treatment included VA shunt, repositioning of the peritoneal catheter, and endoscopic choroid plexus coagulation. Conclusion: CSF hydrothorax is a rare thoracic complication of VP shunt placement with no radiographic evidence of shunt migration or malfunction. Postulated mechanisms include limited peritoneal capacity to resorb CSF in children and microscopic communications present in congenital diaphragmatic hiatuses.

  4. [Intraoperative fluid therapy in infants with congestive heart failure due to intracranial pial arteriovenous fistula].

    Science.gov (United States)

    Arroyo-Fernández, F J; Calderón-Seoane, E; Rodríguez-Peña, F; Torres-Morera, L M

    2016-05-01

    Pial arteriovenous fistula is a rare intracranial congenital malformation (0.1-1: 100,000). It has a high blood flow between one or more pial arteries and drains into the venous circulation. It is usually diagnosed during the childhood by triggering an intracranial hypertension and/or congestive heart failure due to left-right systemic shunt. It is a rare malformation with a complex pathophysiology. The perioperative anaesthetic management is not well established. We present a 6-month-old infant diagnosed with pial arteriovenous fistula with hypertension and congestive heart failure due to left-right shunt. He required a craniotomy and clipping of vascular malformation. Anaesthetic considerations in patients with this condition are a great challenge. It must be performed by multidisciplinary teams with experience in paediatrics. The maintenance of blood volume during the intraoperative course is very important. Excessive fluid therapy can precipitate a congestive heart failure or intracranial hypertension, and a lower fluid therapy may cause a tissue hypoxia due to the bleeding.

  5. Delayed intracerebellar hemorrhage secondary to lumboperitoneal shunt insertion

    Science.gov (United States)

    Er, Uygur; Akyol, Çetin; Bavbek, Murad

    2016-01-01

    Aim of this paper is to present and discuss a case of a delayed cerebellar parenchymal hemorrhage developing after L/P shunt placement with a NPH patient. A hypertensive patient admitted to our clinic with a diagnosis of NPH. The patient was placed a pressure adjustable L/P shunt without any surgical complication. He was discharged with an uneventful period. The patient was admitted to the emergency clinic of our hospital with a 1.5 × 1.5 cm diameter hematoma at the left cerebellar hemisphere on 2 days after his discharge. CSF drainage by an L/P shunt can generate intracerebellar hemorrhages especially in hypertensive patients. PMID:27695558

  6. Endovascular embolization of pulmonary arteriovenous malformations

    Institute of Scientific and Technical Information of China (English)

    LIU Feng-yong; WANG Mao-qiang; FAN Qing-sheng; DUAN Feng; WANG Zhi-jun; SONG Peng

    2010-01-01

    Background The major consequence of pulmonary arteriovenous malformations (PAVMs) is the direct inflow of blood from the pulmonary artery to the pulmonary vein which induces hypoxemia. Severe complications include transient ischemic attacks, paradoxical embolization in the central nervous system, massive hemoptysis or hemothorax, etc. The conventional treatment is surgical intervention. However, this can be very traumatic and dangerous. Endovascular embolization has advantages over surgery such as a faithful therapeutic effect, a low complication rate, repeatability, etc. Methods Patients (n=23) with symptomatic PAVMs underwent endovascular embolization; 11 were males and 12 were females, with ages ranging from 6 months to 58 years. During the embolization, microcoils were applied in 6 cases and standard steel coils were used in 17 cases.Results Multiple PAVMs lesions were found in 16 cases and single PAVMs lesion was found in 7 cases. Embolotherapy was carried out 28 times for 23 patients. The success rate was 100%. The results of pulmonary arteriography after treatment showed that single lesion disappeared completely while the main abnormal vessels in multiple lesions also disappeared. The mean blood oxygen saturation increased from (78.04±8.22)% to (95.13±3.67)% after the procedure. A correlated groups t test showed changes in blood oxygen saturation before and after embolization (fe=9.101, P <0.001). Symptoms of cardiac insufficiency disappeared in 5 cases and vascular murmur in the chest disappeared in 13 cases. After embolization, mild chest pain occurred in 11 cases, small amounts of pleural effusion occurred in 5 cases, and 1 patient died 2 months later because of a pyogenic infection secondary to the pulmonary infarction. Among the 22 remaining cases, with overall follow-up ranging from 18 months to 12 years, general conditions were fine, daily lives were normal and there were no neurologic symptoms or signs, except for 3 patients with diffused PAVMs who

  7. Congenital extrahepatic portosystemic shunts

    Energy Technology Data Exchange (ETDEWEB)

    Murray, Conor P.; Yoo, Shi-Joon; Babyn, Paul S. [Department of Diagnostic Imaging, Hospital for Sick Children, 555 University Avenue, M5G 1X8, Toronto, Ontario (Canada)

    2003-09-01

    A congenital extrahepatic portosystemic shunt (CEPS) is uncommon. A type 1 CEPS exists where there is absence of intrahepatic portal venous supply and a type 2 CEPS where this supply is preserved. The diagnosis of congenital portosystemic shunt is important because it may cause hepatic encephalopathy. To describe the clinical and imaging features of three children with CEPS and to review the cases in the published literature. The diagnostic imaging and medical records for three children with CEPS were retrieved and evaluated. An extensive literature search was performed. Including our cases, there are 61 reported cases of CEPS, 39 type 1 and 22 type 2. Type 1 occurs predominantly in females, while type 2 shows no significant sexual preponderance. The age at diagnosis ranges from 31 weeks of intrauterine life to 76 years. Both types of CEPS have a number of associations, the most common being nodular lesions of the liver (n=25), cardiac anomalies (n=19), portosystemic encephalopathy (n=10), polysplenia (n=9), biliary atresia (n=7), skeletal anomalies (n=5), and renal tract anomalies (n=4). MRI is recommended as an important means of diagnosing and classifying cases of CEPS and examining the associated cardiovascular and hepatic abnormalities. Screening for CEPS in patients born with polysplenia is suggested. (orig.)

  8. Intestinal arteriovenous malformation involving the descending colon: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Jin; Park, Young Chan; Lee, Young Hwan; Jung, Kyung Jae; Kim, Ho Kyun [Catholic University of Daegu, Daegu (Korea, Republic of)

    2007-08-15

    Arteriovenous malformations (AVMs) comprising a feeding artery, nidus, and draining vein rarely develop in the gastrointestinal tract. Although almost all AVMs are asymptomatic, they cause massive painless rectal bleeding and subsequent chronic anemia. The definitive diagnosis of AVM is achieved by selective mesenteric angiography, and surgical resection is the treatment of choice. We detected an intestinal AVM involving the descending colon in a patient with severe hematochezia. The diagnosis was made by CT angiography performed using a 64-channel MDCT and the obtained 3D reconstruction images. The AVM showed an extensive vascular network on CT images, and it was treated by surgical resection. Here, we report this case of an intestinal AVM along with its imaging findings.

  9. Double Coaxial Microcatheter Technique for Glue Embolization of Renal Arteriovenous Malformations

    Energy Technology Data Exchange (ETDEWEB)

    Uchikawa, Yoko, E-mail: jauchikawa@gmail.com [University of Tsukuba Hospital, Department of Radiology (Japan); Mori, Kensaku, E-mail: moriken@md.tsukuba.ac.jp [University of Tsukuba, Department of Radiology, Faculty of Medicine (Japan); Shiigai, Masanari, E-mail: m-41gai@yahoo.co.jp [Tsukuba Medical Center Hospital, Department of Radiology (Japan); Konishi, Takahiro, E-mail: soratobukangaruu@gmail.com [University of Tsukuba Hospital, Department of Radiology (Japan); Hoshiai, Sodai, E-mail: hoshiai@sb4.so-net.ne.jp [Ibaraki Prefectural Central Hospital, Department of Radiology (Japan); Ishigro, Toshitaka, E-mail: suzutokei@gmail.com; Hiyama, Takashi, E-mail: med-tak@hotmail.com [University of Tsukuba Hospital, Department of Radiology (Japan); Nakai, Yasunobu, E-mail: nakaiya@tmch.or.jp [Tsukuba Medical Center Hospital, Department of Neurosurgery (Japan); Minami, Manabu, E-mail: mminami@md.tsukuba.ac.jp [University of Tsukuba, Department of Radiology, Faculty of Medicine (Japan)

    2015-10-15

    PurposeTo demonstrate the technical benefit of the double coaxial microcatheter technique for embolization of renal arteriovenous malformations (AVMs) with n-butyl cyanoacrylate and iodized oil (glue).Materials and MethodsSix consecutive patients (1 man and 5 women; mean age 61 years; range 44–77 years) with renal AVMs were included. Five patients had hematuria, and one had a risk of heart failure due to a large intrarenal arteriovenous shunt. All patients underwent transarterial embolization using glue and the double coaxial microcatheter technique with outer 2.6F and inner 1.9F microcatheters. After glue injection, the inner microcatheter was retracted, while the outer microcatheter was retained. We assessed the complications and clinical outcomes of this technique.ResultsTechnical success was achieved in all patients. In 9 sessions, 34 feeding arteries were embolized with glue using the double coaxial microcatheter technique, 1 was embolized with glue using a single microcatheter, and 2 were embolized with coils. The double coaxial microcatheter technique was useful for selecting small tortuous feeding arteries, preventing glue reflux to the proximal arteries, and approaching multiple feeding arteries without complete retraction of the microcatheters. As a minor complication, glue migrated into the venous system in four patients without any sequelae. In all patients, favorable clinical outcomes, including hematuria cessation in five patients and improvement of the large intrarenal arteriovenous shunt in one patient, were obtained without deterioration of renal function.ConclusionGlue embolization with the double coaxial microcatheter technique was useful for treating renal AVMs with multiple tortuous feeding arteries.

  10. Favorable results with syringosubarachnoid shunts for treatment of syringomyelia.

    Science.gov (United States)

    Tator, C H; Meguro, K; Rowed, D W

    1982-04-01

    From 1969 to 1979, 20 patients with syringomyelia were treated with a syringosubarachnoid shunt. The principal indications for this procedure were: significant progressive neurological deterioration and absent or minimal tonsillar ectopia. There were 15 patients with idiopathic syringomyelia, four with posttraumatic syringomyelia, and one with syringomyelia secondary to spinal arachnoiditis. The operations were performed with an operating microscope, and attention was directed to preserving thearachnoid membrane to ensure proper placement of the distal end of the shunt in an intact subarachnoid space. In all cases, a silicone rubber ventricular catheter was inserted into the syrinx through a posterior midline myelotomy. The average follow-up period was 5 years. A favorable result was obtained in 15 of the 20 patients (75%), including an excellent result with improvement of neurological deficit in 11 patients and a good result with cessation of progression in four patients. In the remaining five patients the result was poor with further progression of neurological deficit. A short duration of preoperative symptoms was usually a favorable prognostic feature. Four patients with a history of less than 6 months all had excellent results. Thirteen patients had a syringosubarachnoid shunt only, and all had good or excellent results. Seven patients had other surgical procedures, before, accompanying, or after shunt placement, and two had favorable results. Thus, the syringosubarachnoid shunt is an effective therapeutic modality for many patients with syringomyelia, particularly if there is little or no tonsillar herniation.

  11. Early mediastinal seroma secondary to modified Blalock-Taussig shunts - successful management by percutaneous drainage

    Energy Technology Data Exchange (ETDEWEB)

    Connolly, Bairbre L.; Temple, Michael J.; Chait, Peter G.; Restrepo, Ricardo [Department of Diagnostic Imaging, Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, Ontario M5G 1X8 (Canada); Adatia, Ian [Department of Cardiology and Critical Care Medicine, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, Ontario M5G 1X8 (Canada)

    2003-07-01

    Large symptomatic mediastinal seroma following modified-BT shunts, traditionally required revisional thoracotomy. We describe percutaneous image-guided pigtail catheter drainage in the successful treatment of early mediastinal seroma secondary to PTFE Blalock-Taussig shunt, avoiding thoracotomy. A retrospective review of all relevant clinical and imaging records in five patients was performed. All five presented with intermittent stridor, respiratory distress and/or episodic desaturation within 6 weeks of their surgery. In four of five infants, percutaneous drainage was effective and reoperation was avoided. In one of five, rather than urgent surgical evacuation and BT shunt revision, we were able to perform an elective stage-II bidirectional Glenn SVC-RA anastamosis in a stable infant. There were no complications. Percutaneous image-guided drainage of mediastinal seroma secondary to PTFE-BT shunt is a safe, minimally invasive, and effective treatment. This may avoid BT shunt revision. (orig.)

  12. [Altitude, the ratio of PaO2 to fraction of inspired oxygen, and shunt: impact on the assessment of acute lung injury].

    Science.gov (United States)

    Pérez-Padilla, J R

    2004-10-01

    The ratio of PaO2 to the fraction of inspired oxygen (PaO2/FIO2) is commonly used to determine the severity of acute lung injury and acute respiratory distress syndrome (ARDS). The research presented here used computational models of the lung to analyze the effect of altitude on the PaO2/FIO2 ratio and pulmonary shunt. At a given shunt, the PaO2/FIO2 ratio is lower at higher altitudes. Therefore, when evaluating for ARDS based on a PaO2/FIO2 ratio of <200 mm Hg, patients residing at high altitudes will have less shunt and, presumably, less severe lung injury than patients at sea level. This should be taken into consideration when comparing patients from different altitudes. Shunt should more often be measured directly or be estimated assuming a constant arteriovenous oxygen content difference.

  13. Systemic-pulmonary arteriovenous fistula of traumatic origin: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Hirsch, M.; Maroko, I.; Gueron, M.; Goleman, L.

    1983-08-01

    Arteriovenous fistulas between the systemic circulation and the pulmonary artery are extremely rare. Continuous precordial murmur is the usual clinical sign while unilateral rib notching may be the only radiologic manifestation of this condition. Selective angiographic investigation is necessary to localize the site of such an arteriovenous (AV) fistula before surgery is performed. In a review of the literature of 15 published cases, the majority were of congenital origin, with four of these systemic-pulmonary AV fistulas of traumatic origin, of which one occurred after insertion of an intercostal catheter. We describe one case of traumatic origin 9 years after percutaneous thoracic drainage for spontaneous pneumothorax, in which transcatheter embolic occlusion of the feeding arteries of an AV fistula was attempted. The advantages and the disadvantages of the non-surgical and surgical therapeutic approaches are discussed.

  14. What Is an Arteriovenous Malformation (AVM)?

    Science.gov (United States)

    ... T. Quiz 5 Things to Know About Stroke What Is an Arteriovenous Malformation (AVM)? Updated:Nov 21, ... About AVMs Symptoms and Bleeding Diagnosis and Treatment What is a brain AVM? Normally, arteries carry blood ...

  15. Gamma knife radiosurgery for cerebral arteriovenous malformations.

    Science.gov (United States)

    Kemeny, A A; Radatz, M W R; Rowe, J G; Walton, L; Hampshire, A

    2004-01-01

    Since its introduction, gamma knife radiosurgery has become an important treatment modality for cerebral arteriovenous malformations. This paper is a brief overview of the technique used, of the clinical results achieved and of the experience gained in Sheffield.

  16. Liver resection for the treatment of a congenital intrahepatic portosystemic venous shunt

    Institute of Scientific and Technical Information of China (English)

    Michail Papamichail; Amir Ali; Alberto Quaglia; John Karani; Nigel Heaton

    2015-01-01

    Intrahepatic portosystemic shunts (IPSS) are rare congenital anomalies arising from disordered portal vein em-bryogenesis. It has been described in both children and adults and may be asymptomatic or be associated with a variety of neurophysiological and pulmonary complications. When rec-ognized, early intervention to occlude the shunt will reverse the associated complications. Literature review reports of surgical and radiological occlusion of the shunt, but due to its rarity, a standard therapeutic protocol has not been established. A case of a 38-year-old woman with abdominal pain and low grade encephalopathy, diagnosed with an IPSS and treated by right hepatectomy was reported.

  17. Liver resection for the treatment of a congenital intrahepatic portosystemic venous shunt

    Institute of Scientific and Technical Information of China (English)

    Michail Papamichail; Amir Ali; Alberto Quaglia; John Karani; Nigel Heaton

    2016-01-01

    Intrahepatic portosystemic shunts (IPSS) are rare congenital anomalies arising from disordered portal vein em-bryogenesis. It has been described in both children and adults and may be asymptomatic or be associated with a variety of neurophysiological and pulmonary complications. When rec-ognized, early intervention to occlude the shunt will reverse the associated complications. Literature review reports of surgical and radiological occlusion of the shunt, but due to its rarity, a standard therapeutic protocol has not been established. A case of a 38-year-old woman with abdominal pain and low grade encephalopathy, diagnosed with an IPSS and treated by right hepatectomy was reported.

  18. Characteristics, diagnosis and treatment of hypoglossal canal dural arteriovenous fistula: report of nine cases

    Energy Technology Data Exchange (ETDEWEB)

    Manabe, Shinji; Satoh, Koichi; Matsubara, Shunji; Satomi, Junichiro; Hanaoka, Mami; Nagahiro, Shinji [University of Tokushima, Department of Neurosurgery, Tokushima (Japan)

    2008-08-15

    We report the characteristics, diagnosis and treatment of dural arteriovenous fistula (DAVF) of the hypoglossal canal in nine patients with this relatively rare vascular disorder. Of 248 patients with intracranial DAVFs managed at our institution, nine patients (3.6%; four men, five women; mean age 62 years) were diagnosed with hypoglossal canal DAVF. We investigated patient characteristics with respect to clinical symptoms, neuroradiological findings, efficacy and complications related to endovascular treatment. Seven patients had experienced head injury. All patients presented with pulsatile tinnitus. One patient displayed ipsilateral hypoglossal nerve palsy before treatment. MR angiography showed a 'magic wand' appearance between the affected hypoglossal canal and the internal jugular vein in four patients. Angiography demonstrated an AV fistula on the medial aspect of the superior jugular bulb, mostly arising from the bilateral occipital, ascending pharyngeal and vertebral arteries with drainage to the internal jugular vein via the anterior condylar vein. Contralateral carotid injection accurately clarified the shunting point. Five patients underwent endovascular treatment: transarterial embolization (TAE; n=2), transvenous embolization (TVE; n=2), and TAE/TVE (n=1). Complete shunt obliteration was achieved in four patients and shunt reduction in one. The remaining four patients were treated conservatively and the shunt had disappeared at follow-up. Postoperative hypoglossal nerve palsy occurred in one patient after TVE, possibly due to coil overpacking. The incidence of hypoglossal canal DAVF was not very low in our series. Contralateral carotid injection is an essential examination to provide an accurate diagnosis. TVE should be considered when access is available, although TAE is also appropriate for shunt reduction. (orig.)

  19. Incarceration of umbilical hernia after radiological insertion of a Denver peritoneovenous shunt.

    Science.gov (United States)

    Ohta, Kengo; Shimohira, Masashi; Hashizume, Takuya; Kawai, Tatsuya; Kurosaka, Kenichiro; Suzuki, Kazushi; Watanabe, Kenichi; Shibamoto, Yuta

    2013-03-01

    We report a rare complication of incarceration of an umbilical hernia after Denver peritoneovenous shunt placement. A 50-year-old man presented with refractory ascites from liver cirrhosis. He also had an umbilical hernia. Because the ascites became uncontrollable, Denver peritoneovenous shunting was performed. The operation was successful and the ascites decreased. Ten days later, however, incarceration of the umbilical hernia occurred. A surgical repair was performed, but he died 2 days later. The cause of death was considered to be sepsis.

  20. Arteriovenøs fistel efter skudlaesion. Kvalitativ og kvantitativ diagnosticering

    DEFF Research Database (Denmark)

    Beck, A M; Bülow, J B; Mortensen, D P

    1989-01-01

    A man aged 33 years developed an arterio-venous fistula following a gunshot wound from behind in the right calf. The quality of the fistula could be demonstrated employing digital subtraction angiographic technique while the quantity was demonstrated employing 99Tc macroaggregated albumin....... The localization of the fistula is important in view of the surgical procedure and the haemodynamic amount is important to determine cardiac involvement....

  1. Long term follow-up of 43 pure dural arteriovenous fistulae (AVF) of the lateral sinus

    Energy Technology Data Exchange (ETDEWEB)

    Fermand, M.; Reizine, D.; Melki, J.P.; Riche, M.C.; Merland, J.J.

    1987-07-01

    Fourty-three patients with arterio-venous fistulae of the dura of the transverse sinus with a complaint of tinnitus are reviewed, with a follow-up of 12 months to 11 years. 34 patients were embolized, 2 treated surgically, and 7 were untreated. Embolization appears to have been beneficial. The benign nature of this abnormality must be emphasized, and serious psychological study of the patient must be made before deciding on therapy.

  2. Multimodality evaluation of dural arteriovenous fistula with CT angiography, MR with arterial spin labeling, and digital subtraction angiography: case report.

    Science.gov (United States)

    Alexander, Matthew; McTaggart, Ryan; Santarelli, Justin; Fischbein, Nancy; Marks, Michael; Zaharchuk, Greg; Do, Huy

    2014-01-01

    Dural arteriovenous fistulae (DAVF) are cerebrovascular lesions with pathologic shunting into the venous system from arterial feeders. Digital subtraction angiography (DSA) has long been considered the gold standard for diagnosis, but advances in noninvasive imaging techniques now play a role in the diagnosis of these complex lesions. Herein, we describe the case of a patient with right-side pulsatile tinnitus and DAVF diagnosed using computed tomography angiography, magnetic resonance with arterial spin labeling, and DSA. Implications for imaging analysis of DAVFs and further research are discussed.

  3. Paroxysmal supraventricular tachycardia as first manifestation of right atrial hemangioma during endovascular treatment of intracranial arteriovenous fistulas.

    Science.gov (United States)

    Spanò, Francesca; Cereda, Alberto; Moreo, Antonella; Bonacina, Edgardo; Peritore, Angelica; Roghi, Alberto; Giannattasio, Cristina; Pedrotti, Patrizia

    2015-06-10

    We report the description of a cardiac mass occupying almost the entire right atrium in a young man who developed paroxysmal supraventricular tachycardia during endovascular treatment of intracranial arteriovenous fistulas. The mass was detected at echocardiographic examination, its tissue characteristics were defined with cardiac magnetic resonance and it was successfully surgically removed. The histopathological findings were consistent with a mixed type cavernous-capillary hemangioma of the heart. The intriguing co-existence of cardiac hemangioma and cerebral arteriovenous fistulas, to the best of our knowledge, has not been previously reported in English Literature.

  4. Medical image of the week: pulmonary arteriovenous fistula

    Directory of Open Access Journals (Sweden)

    Bajracharya M

    2014-04-01

    Full Text Available No abstract available. Article truncated after 150 words. A 60 year-old man with hepatic cirrhosis, was referred for chest pain, shortness of breath, and progressive cyanosis and an echocardiographic evaluation. PaO2 was 64 mm Hg on room air, but only 74 mm Hg on 100% oxygen. Chest X-ray and pulmonary function testing were normal. A contrast echocardiography using agitated saline (bubble study was performed. A delayed appearance of a substantial amount of micro-bubbles in the left atrium greater than three cardiac cycles after appearance in the right atrium and ventricle was suggestive of pulmonary arteriovenous fistula (Figure 1A. The delayed appearance and a large amount of micro-bubbles in the left atrium preclude the intracardiac shunting result of a patent foramen ovale (PFO or atrial septal defect (ASD. Interestingly, the density of micro-bubbles were same in the left and the right cardiac chambers even after 10 cardiac cycles (Figure 1B and 1C. When the injection was stopped, there were ...

  5. Staged Transcatheter Treatment of Portal Hypoplasia and Congenital Portosystemic Shunts in Children

    Energy Technology Data Exchange (ETDEWEB)

    Bruckheimer, Elchanan, E-mail: elchananb@bezeqint.net; Dagan, Tamir [Schneider Children' s Medical Center Israel, Section of Pediatric Cardiology (Israel); Atar, Eli; Schwartz, Michael [Schneider Children' s Medical Center Israel, Section of Radiology (Israel); Kachko, Ludmila [Schneider Children' s Medical Center Israel, Section of Anesthesiology (Israel); Superina, Riccardo; Amir, Gabriel [Schneider Children' s Medical Center Israel, Section of Pediatric Cardiology (Israel); Shapiro, Rivka [Schneider Children' s Medical Center Israel, Section of Gastroenterology (Israel); Birk, Einat [Schneider Children' s Medical Center Israel, Section of Pediatric Cardiology (Israel)

    2013-12-15

    Purpose: Congenital portosystemic shunts (CPSS) with portal venous hypoplasia cause hyperammonemia. Acute shunt closure results in portal hypertension. A transcatheter method of staged shunt reduction to afford growth of portal vessels followed by shunt closure is reported. Methods: Pressure measurements and angiography in the CPSS or superior mesenteric artery (SMA) during temporary occlusion of the shunt were performed. If vessels were diminutive and the pressure was above 18 mmHg, a staged approach was performed, which included implantation of a tailored reducing stent to reduce shunt diameter by {approx}50 %. Recatheterization was performed approximately 3 months later. If the portal pressure was below 18 mmHg and vessels had developed, the shunt was closed with a device. Results: Six patients (5 boys, 1 girl) with a median age of 3.3 (range 0.5-13) years had CPSS portal venous hypoplasia and hyperammonemia. Five patients underwent staged closure. One patient tolerated acute closure. One patient required surgical shunt banding because a reducing stent could not be positioned. At median follow-up of 3.8 (range 2.2-8.4) years, a total of 21 procedures (20 transcatheter, 1 surgical) were performed. In all patients, the shunt was closed with a significant reduction in portal pressure (27.7 {+-} 11.3 to 10.8 {+-} 1.8 mmHg; p = 0.016), significant growth of the portal vessels (0.8 {+-} 0.5 to 4.0 {+-} 2.4 mm; p = 0.037), and normalization of ammonia levels (202.1 {+-} 53.6 to 65.7 {+-} 9.6 {mu}mol/L; p = 0.002) with no complications. Conclusion: Staged CPSS closure is effective in causing portal vessel growth and treating hyperammonemia.

  6. Partially trombosed glomus type spinal arteriovenous malformation – case presentation

    Directory of Open Access Journals (Sweden)

    Gorgan M.R.

    2014-12-01

    Full Text Available Spinal AVM are very rare vascular lesions and most o the studies give reports on only a few cases. Given their localization between the spinal tracts and the gray matter core of the medulla and their multiple feeders from posterior and anterior spinal arteries they are amongst the most difficult surgical pathology in the nervous sistem. We present the case of a 60 years old male with a glomus type T10-L2 spinal AVM that presented with motor deficit in the lower limbs and urinary incontinence. The partially thrombosed lesion was completely resected without previous embolisation, and the patient was walking with assistance at discharge. This is a rare case that presented with progressive neurological deterioration consistent with an ischemic rather than a hemorrhagic event. Microsurgery is a better option than conservative treatment in these rare cases of spontaneous occlusion of intramedullary arteriovenous malformations.

  7. Stent graft repair of iatrogenic femoral arteriovenous fistula: a useful therapeutic approach in a hostile groin.

    Science.gov (United States)

    De Martino, Randall R; Nolan, Brian W; Powell, Richard J; Walsh, Daniel B; Stone, David H

    2010-01-01

    The incidence of iatrogenic femoral arteriovenous fistulas (IFAVF) has increased in contemporary practice. We herein report the case of a 55-year-old obese woman with significant surgical comorbidities who sustained an IFAVF between the superficial femoral artery (SFA) and the femoral vein. Given her substantial risk factors, she was treated with a SFA stent-graft (iCast 6 x 22 mm) using a contralateral endovascular approach. She remains asymptomatic at 15 months with ongoing resolution of the AVF. This report highlights the utility of stent-graft repair of an IFAVF in high surgical risk patients or in those with ''hostile'' anatomy.

  8. Cerebellar arteriovenous malformations in children

    Energy Technology Data Exchange (ETDEWEB)

    Griffiths, P.D. [Sheffield Univ. (United Kingdom). Acad. Dept. of Radiol.; Blaser, S.; Armstrong, D.; Chuang, S.; Harwood-Nash, D. [Division of Neuroradiology, The Hospital for Sick Children and University of Toronto, Toronto (Canada); Humphreys, R.P. [Division of Neurosurgery, The Hospital for Sick Children and University of Toronto, Toronto (Canada)

    1998-05-01

    We review the presentation, imaging findings and outcome in 18 children with cerebellar arteriovenous malformations (AVM). This group is of particular interest because of the reported poor outcome despite modern imaging and neurosurgical techniques. All children had CT and 15 underwent catheter angiography at presentation. Several of the children in the latter part of the study had MRI. Of the 18 children, 17 presented with a ruptured AVM producing intracranial haemorrhage. The remaining child presented with temporal lobe epilepsy and was shown to have temporal, vermian and cerebellar hemisphere AVM. This child had other stigmata of Osler-Weber-Rendu syndrome. Three other children had pre-existing abnormalities of possible relevance. One had a vascular malformation of the cheek and mandible, one a documented chromosomal abnormality and another a midline cleft upper lip and palate. Six of the 17 children with a ruptured cerebellar AVM died within 7 days of the ictus. Vascular pathology other than an AVM was found in 10 of the 14 children with a ruptured cerebellar AVM who had angiography: 4 intranidal aneurysms, 5 venous aneurysms and 2 cases of venous outflow obstruction (one child having both an aneurysm and obstruction). The severity of clinical presentation was directly related to the size of the acute haematoma, which was a reasonable predictor of outcome. (orig.) With 4 figs., 4 tabs., 23 refs.

  9. Piezoelectric RL shunt damping of flexible structures

    DEFF Research Database (Denmark)

    Høgsberg, Jan Becker; Krenk, Steen

    2015-01-01

    Resonant RL shunt circuits represent a robust and effective approach to piezoelectric damping, provided that the individual shunt circuit components are calibrated accurately with respect to the dynamic properties of the corresponding flexible structure. The balanced calibration procedure applied...

  10. An Intra-Abdominal Pseudocyst around a Ventriculoperitoneal Shunt due to Streptococcus Infection 7 Years after Shunt Surgery

    Directory of Open Access Journals (Sweden)

    Arata Tomiyama

    2014-01-01

    Full Text Available In 1999, a 50-year-old woman underwent ventriculoperitoneal (VP shunt surgery for hydrocephalus after subarachnoid hemorrhage. She was hospitalized for fever and recurrent systemic seizures in November 2006. Head computed tomography (CT showed only old changes. The seizures and fever were controlled by medicinal therapy. However, in December, her consciousness level suddenly decreased, and she showed progressive lower abdominal distension. Head CT showed marked ventriculomegaly, and abdominal CT showed a giant cystic mass at the shunt-tube tip in the lower abdominal cavity. Because thick pus was aspirated from the intra-abdominal mass, we diagnosed the patient with acute obstructive hydrocephalus due to an infected abdominal pseudocyst. Laparotomy and direct cyst drainage were performed, and antibiotic therapy against Streptococcus, the causative pathogen, was administered. The VP shunt tube was replaced. The postoperative course was uneventful, and postoperative CT showed hydrocephalus improvement and no pseudocyst recurrence. Abdominal pseudocysts, which are rare after VP shunt surgeries, usually occur after the subacute postoperative course in younger cerebral hemorrhagic cases. Our case was quite rare because the cyst developed in the chronic phase in an older patient and was caused by streptococcal infection. The cyst components should be examined before cyst drainage when choosing surgical strategies.

  11. Shunting ratios for MHD flows

    Energy Technology Data Exchange (ETDEWEB)

    Birzvalk, Yu.

    1978-01-01

    The shunting ratio and the local shunting ratio, pertaining to currents induced by a magnetic field in a flow channel, are properly defined and systematically reviewed on the basis of the Lagrange criterion. Their definition is based on the energy balance and related to dimensionless parameters characterizing an MHD flow, these parameters evolving from the Hartmann number and the hydrodynamic Reynolds number as well as the magnetic Reynolds number, and the Lundquist number. These shunting ratios, of current density in the core of a stream (uniform) or equivalent mean current density to the short-circuit (maximum) current density, are given here for a slot channel with nonconducting or conducting walls, for a conduction channel with heavy side rails, and for an MHD-flow around bodies. 5 references, 1 figure.

  12. Stent graft placement for dysfunctional arteriovenous grafts

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Gyeong Sik [Dept. of Radiology, CHA Bundang Medical Center, College of Medicine, CHA University, Seongnam (Korea, Republic of); Shin, Byung Seok; Ohm, Joon Young; Ahn, Moon Sang [Chungnam National University Hospital, Daejeon (Korea, Republic of)

    2015-07-15

    This study aimed to evaluate the usefulness and outcomes of stent graft use in dysfunctional arteriovenous grafts. Eleven patients who underwent stent graft placement for a dysfunctional hemodialysis graft were included in this retrospective study. Expanded polytetrafluoroethylene covered stent grafts were placed at the venous anastomosis site in case of pseudoaneurysm, venous laceration, elastic recoil or residual restenosis despite the repeated angioplasty. The patency of the arteriovenous graft was evaluated using Kaplan-Meier analysis. Primary and secondary mean patency was 363 days and 741 days. Primary patency at 3, 6, and 12 months was 82%, 73%, and 32%, respectively. Secondary patency at the 3, 6, 12, 24, and 36 months was improved to 91%, 82%, 82%, 50%, and 25%, respectively. Fractures of the stent graft were observed in 2 patients, but had no effect on the patency. Stent graft placement in dysfunctional arteriovenous graft is useful and effective in prolonging graft patency.

  13. Laparoscopic Cholecystectomy for a Patient with a Lumboperitoneal Shunt: A Rare Case.

    Science.gov (United States)

    Rumba, Roberts; Vanags, Andrejs; Strumfa, Ilze; Pupkevics, Andrejs; Pavars, Maris

    2016-01-01

    A rare factor that can complicate the perioperative course of laparoscopic cholecystectomy is previous placement of a lumboperitoneal (LP) shunt. Thus far, only two articles describing this situation have been published. Here, we report on a 41-year-old female patient with gallstone disease and a LP shunt placement in the preceding year due to idiopathic intracranial hypertension. It is a syndrome of increased intracranial pressure without any known cause that mainly affects young obese women. The patient was operated upon using standard port placement and peritoneal insufflation. The postoperative period was uneventful and the patient was discharged shortly after the procedure. Due to the increasing incidence and prevalence of obesity, the number of general surgical patients with a LP shunt will likely increase. Based on our experience and evidence in the literature, we conclude that performing a laparoscopy for a patient with a LP shunt is safe.

  14. Left pulmonary artery banding to repair ipsilateral diffuse pulmonary arteriovenous fistula

    Directory of Open Access Journals (Sweden)

    Hirata Takuya

    2012-08-01

    Full Text Available Abstract Congenital pulmonary arteriovenous fistula (PAVF is a rare disease which causes hypoxemia by shunting deoxygenated blood from the pulmonary artery into pulmonary venous return. Lung transplantation is the most effective therapy to treat severe, diffuse PAVF. However, the availability of lungs for transplantation is limited in most parts in the world. For patients with diffuse PAVF affecting only one side of the lungs, ipsilateral pulmonary artery banding (PAB is an effective treatment, but not yet standard of care. We report successful treatment of a patient with diffuse left-sided PAVF with PAB. We believe that PAB is an effective therapy for severe unilateral PAVF and may serve as a bridge to lung transplantation.

  15. Microscope-assisted endoscopic interlaminar ligation of spinal arteriovenous fistulas: technical note.

    Science.gov (United States)

    Wang, Chen; Chen, Chien-Min; Shen, Fang; Fang, Xiao-Dong; Ying, Guang-Yu; Ren, Yu-Cheng; Yu, Dan-Feng; Zhu, Liang-Liang; Zhu, Yong-Jian; Zhang, Jian-Min

    2016-09-01

    Spinal dural arteriovenous fistulas (SDAVFs) are the most common type of spinal arteriovenous malformations, and microsurgical ligation is the treatment modality most frequently used for these lesions. Developments in endoscopic techniques have made endoscopy an even less invasive alternative to routine microsurgical approaches in spine surgery, but endoscopic management of SDAVF or other intradural spinal lesions has not been reported to date. The authors describe the use of a microscope-assisted endoscopic interlaminar approach for the ligation of the proximal draining vein of an L-1 SDAVF in a 58-year-old man. A complete cure was confirmed by postoperative angiography. The postoperative course was uneventful, and short-term follow-up showed improvements in the patient's neurological function. The authors conclude that the endoscopic interlaminar approach with microscope assistance is a safe, minimally invasive, innovative technique for the surgical management of SDAVFs in selected patients.

  16. Cerebral oxygenation and processed EEG response to clamping and shunting during carotid endarterectomy under general anesthesia.

    Science.gov (United States)

    Perez, William; Dukatz, Christopher; El-Dalati, Sami; Duncan, James; Abdel-Rasoul, Mahmoud; Springer, Andrew; Go, Michael R; Dzwonczyk, Roger

    2015-12-01

    Clamping and shunting during carotid endarterectomy (CEA) surgery causes changes in cerebral blood flow. The purpose of this study was to assess and compare, side by side, the cerebral oxygenation (rSO2) and processed electroencephalogram (EEG) response bilaterally to carotid artery clamping and shunting in patients undergoing CEA under general anesthesia. With institutional approval and written informed consent, patients undergoing CEA under general anesthesia and routine carotid artery shunting were recorded bilaterally, simultaneously and continuously with an rSO2 and processed EEG monitor. The response of the monitors during carotid artery clamping and shunting were assessed and compared between monitors and bilaterally within each monitor. Sixty-nine patients were included in the study. At clamping the surgical-side and contralateral-side rSO2 dropped significantly below the baseline incision value (-17.6 and -9.4% respectively). After shunting, the contralateral-side rSO2 returned to baseline while the surgical-side rSO2 remained significantly below baseline (-9.0%) until the shunt was removed following surgery. At clamping the surgical-side and contralateral-side processed EEG also dropped below baseline (-19.9 and -20.6% respectively). However, following shunt activation, the processed EEG returned bilaterally to baseline. During the course of this research, we found the rSO2 monitor to be clinically more robust (4.4% failure rate) than the processed EEG monitor (20.0% failure rate). There was no correlation between the rSO2 or processed EEG changes that occurred immediately after clamping and the degree of surgical side stenosis measured pre-operatively. Both rSO2 and processed EEG respond to clamping and shunting during CEA. Cerebral oximetry discriminates between the surgical and contralateral side during surgery. The rSO2 monitor is more reliable in the real-world clinical setting. Future studies should focus on developing algorithms based on these

  17. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

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    Full Text Available ... What are the limitations of TIPS? What is a Transjugular Intrahepatic Portosystemic Shunt (TIPS)? A transjugular intrahepatic ... encourage linking to this site. × Recommend RadiologyInfo to a friend Send to (friend's e-mail address): From ( ...

  18. Four-dimensional computed tomography angiographic evaluation of cranial dural arteriovenous fistula before and after embolization

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Bing, E-mail: bing.tian@hotmail.com; Xu, Bing, E-mail: aishanli0102@126.com; Lu, Jianping, E-mail: tianbing2003@163.com; Liu, Qi, E-mail: liuqimd@126.com; Wang, Li, E-mail: wangli_changhai@163.com; Wang, Minjie, E-mail: cjr.wangminjie@vip.163.com

    2015-06-15

    Highlights: • 4D CTA showed excellent agreement with DSA with regard to identification of feeding arteries and drainage veins. • The most important finding was 4D CTA in determining the impact of DAVF treatment with transarterial embolization. • 4D CTA provides images similar to those obtained with DSA both before and after treatment. - Abstract: Purpose: This study aimed to evaluate the usefulness of four-dimensional CTA before and after embolization treatment with ONYX-18 in eleven patients with cranial dural arteriovenous fistulas, and to compare the results with those of the reference standard DSA. Patients and Methods: Eleven patients with cranial dural arteriovenous fistulas detected on DSA underwent transarterial embolization with ONYX-18. Four-dimensional CTA was performed an average of 2 days before and 4 days after DSA. Four-dimensional CTA and DSA images were reviewed by two neuroradiologists for identification of feeding arteries and drainage veins and for determining treatment effects. Interobserver and intermodality agreement between four-dimensional CTA and DSA were assessed. Results: Forty-two feeding arteries were identified for 14 fistulas in the 11 patients. Of these, 36 (85.71%) were detected on four-dimensional CTA. After transarterial embolization, one patient got partly embolized, and the fistulas in the remaining 10 patients were completely occluded. The interobserver agreement for four-dimensional CTA and intermodality agreement between four-dimensional CTA and DSA were excellent (κ = 1) for shunt location, identification of drainage veins, and fistula occlusion after treatment. Conclusion: Four-dimensional CTA images are highly accurate when compared with DSA images both before and after transarterial embolization treatment. Four-dimensional CTA can be used for diagnosis as well as follow-up of cranial dural arteriovenous fistulas in clinical settings.

  19. Pre-Liver Transplant: Tips Versus Distal Splenorenal Shunt

    Directory of Open Access Journals (Sweden)

    Thomas W. Faust

    1997-01-01

    Full Text Available Recurrent variceal bleeding in liver transplant candidates with end-stage liver disease can complicate or even prohibit a subsequent transplant procedure (OLT. Endoscopic sclero-therapy and medical therapy are considered as first-line management with surgical shunts reserved for refractory situations. Surgical shunts can be associated with a high mortality in this population and may complicate subsequent OLT. The transjugular intrahepatic portosystemic shunt (TIPS has been recommended in these patients as a bridge to OLT. This is a new modality that has not been compared with previously established therapies such as the distal splenorenal shunt (DSRS. In this study we report our experience with 35 liver transplant recipients who had a previous TIPS (18 patients or DSRS (17 patients for variceal bleeding. The TIPS group had a significantly larger proportion of critically ill and Child-Pugh C patients. Mean operating time was more prolonged in the DSRS group (P=0.014 but transfusion requirements were similar. Intraoperative portal vein blood flow measurements averaged 2132±725 ml/min in the TIPS group compared with 1120±351ml/min in the DSRS group (P<0.001. Arterial flows were similar. Mean ICU and hospital stays were similar. There were 3 hospital mortalities in the DSRS group and none in the TIPS group (P=0.1. We conclude that TIPS is a valuable tool in the management of recurrent variceal bleeding prior to liver transplantation. Intra0Perative hemodynamic measurements suggest a theoretical advantage with TIPS. In a group of patients with advanced liver disease we report an outcome that is similar to patients treated with DSRS prior to liver transplantation. The role of TIPS in the treatment of nontransplant candidates remains to be clarified.

  20. Coronary Arteriovenous Fistula Causing Hydrops Fetalis

    Directory of Open Access Journals (Sweden)

    Nilüfer Çetiner

    2014-01-01

    Full Text Available Fetal heart failure and hydrops fetalis may occur due to systemic arteriovenous fistula because of increased cardiac output. Arteriovenous fistula of the central nervous system, liver, bone or vascular tumors such as sacrococcygeal teratoma were previously reported to be causes of intrauterine heart failure. However, coronary arteriovenous fistula was not reported as a cause of fetal heart failure previously. It is a rare pathology comprising 0.2–0.4% of all congenital heart diseases even during postnatal life. Some may remain asymptomatic for many years and diagnosed by auscultation of a continuous murmur during a routine examination, while a larger fistulous coronary artery opening to a low pressure cardiac chamber may cause ischemia of the affected myocardial region due to steal phenomenon and may present with cardiomyopathy or congestive heart failure during childhood. We herein report a neonate with coronary arteriovenous fistula between the left main coronary artery and the right ventricular apex, who presented with hydrops fetalis during the third trimester of pregnancy.

  1. Endovascular treatment of hemodialysis arteriovenous fistulas

    DEFF Research Database (Denmark)

    Heerwagen, Søren T; Hansen, Marc A; Schroeder, Torben V;

    2012-01-01

    Purpose: The purpose of this study was to investigate if the immediate hemodynamic outcome of an endovascular intervention on a dysfunctional hemodialysis arteriovenous fistula is a prognostic factor for primary patency. Methods: This was a prospective observational study including 61 consecutive...

  2. Scimitar syndrome with pulmonary arteriovenous fistulas.

    Science.gov (United States)

    Le Rochais, J P; Icard, P; Davani, S; Abouz, D; Evrard, C

    1999-10-01

    Right abnormal pulmonary venous return into the inferior vena cava associated with abnormal fissure, dextrocardia, and systemic arterial supply of a variable degree, are the characteristics of the scimitar syndrome. We report on a patient in whom this rare syndrome was associated with pulmonary arteriovenous fistulas within the involved lung.

  3. Vector Volume Flow in Arteriovenous Fistulas

    DEFF Research Database (Denmark)

    Hansen, Peter Møller; Heerwagen, Søren; Pedersen, Mads Møller;

    2013-01-01

    , but is very challenging due to the angle dependency of the Doppler technique and the anatomy of the fistula. The angle independent vector ultrasound technique Transverse Oscillation provides a new and more intuitive way to measure volume flow in an arteriovenous fistula. In this paper the Transverse...

  4. Gamma knife radiosurgery for arteriovenous malformation in children

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Takayuki; Kobayashi, Tatsuya [Komaki City Hospital, Aichi (Japan)

    1995-04-01

    Intracranial arteriovenous malformations (AVM) of 38 children were treated by gamma knife radiosurgery. Their clinical courses and the effect of the treatment in 19 patients who had angiographies are described. There were 21 boys and 17 girls with a mean age of 11.2 years. The initial signs and symptoms were: intracranial hemorrhage in 32, seizures in 4, and headache in 2. Prior to the radiosurgery, craniotomy was performed in 10 patients, ventricular drainage, in 8, ventriculoperitoneal shunting in 4, and intravascular embolization in 3. The AVM was in the parietal lobe in 8 patients, in the thalamus in 7, in the occipital lobe in 5, in the temporal lobe in 4, in the basal ganglia in 4, in the corpus callosum in 3, and in other locations in 8. The mean diameter of the nidus was 18.9 mm. According to Spetzler`s classification of AVM, 23 (60.5%) were grade III, 10 were grade II, 3 were grade IV, and 2 were grade VI. The mean maximum dose was 36.3 Gy, and the mean peripheral dose was 20.2 Gy. Follow-up angiography was done in 19 patients during a mean follow-up period of 14.9 months. Complete occlusion of the nidus was obtained within 1 year in 10 of 15 patients (67%). All 6 patients who underwent angiography 2 years after treatment showed complete obliteration of the AVM. Only 1 patient developed hemiparesis due to radiation necrosis. It is considered that occlusion of AVMs by gamma knife radiosurgery is probably more effective and safer in children than in adults. (author).

  5. A novel technique to treat acquired Chiari I malformation after supratentorial shunting

    NARCIS (Netherlands)

    Potgieser, Adriaan R E; Hoving, Eelco W

    2016-01-01

    PURPOSE: The acquired Chiari I malformation with abnormal cranial vault thickening is a rare late complication of supratentorial shunting. It poses a difficult clinical problem, and there is debate about the optimal surgical strategy. Some authors advocate supratentorial skull enlarging procedures w

  6. A new computerized program for surveillance of prosthetic arteriovenous fistulas

    Directory of Open Access Journals (Sweden)

    Matteo Tozzi

    2015-05-01

    Full Text Available Stenosis and thrombosis are common causes of prosthetic vascular access (pVA failure. The role of arteriovenous fistula (AVF surveillance is widely debated. The aim of this paper is to present a new real-time application designed for AVF surveillance called SPIDER. Surgical staff and hemodialysis nurses are responsible for data entry. SPIDER automatically analyses data and generates alerts in case of abnormal trends. Surgical evaluation and duplex Doppler ultrasonography are then immediately performed to confirm presence of stenosis or other possible pVA defects. Surgery can be performed if required. A preliminary analysis of results will be completed at 12 months after the program begins and subsequently after 24 months. Primary assisted patency will be compared with historical using multivariate analysis. Expected results are an improvement in primary assisted pVA patency and reduction of hospitalizations. Simultaneous management of a high number of patients can become difficult due to the large amount of data required for surveillance. We want to demonstrate whether a real-time automated system could help to prevent thrombosis and graft loss.

  7. Transitional Flow in an Arteriovenous Fistula: Effect of Wall Distensibility

    Science.gov (United States)

    McGah, Patrick; Leotta, Daniel; Beach, Kirk; Aliseda, Alberto

    2012-11-01

    Arteriovenous fistulae are created surgically to provide adequate access for dialysis in patients with end-stage renal disease. Transitional flow and the subsequent pressure and shear stress fluctuations are thought to be causative in the fistula failure. Since 50% of fistulae require surgical intervention before year one, understanding the altered hemodynamic stresses is an important step toward improving clinical outcomes. We perform numerical simulations of a patient-specific model of a functioning fistula reconstructed from 3D ultrasound scans. Rigid wall simulations and fluid-structure interaction simulations using an in-house finite element solver for the wall deformations were performed and compared. In both the rigid and distensible wall cases, transitional flow is computed in fistula as evidenced by aperiodic high frequency velocity and pressure fluctuations. The spectrum of the fluctuations is much more narrow-banded in the distensible case, however, suggesting a partial stabilizing effect by the vessel elasticity. As a result, the distensible wall simulations predict shear stresses that are systematically 10-30% lower than the rigid cases. We propose a possible mechanism for stabilization involving the phase lag in the fluid work needed to deform the vessel wall. Support from an NIDDK R21 - DK08-1823.

  8. Ventriculopleural shunting with new technology valves.

    Science.gov (United States)

    Martínez-Lage, J F; Torres, J; Campillo, H; Sanchez-del-Rincón, I; Bueno, F; Zambudio, G; Poza, M

    2000-12-01

    Ventriculoperitoneal shunting constitutes the standard procedure for draining cerebrospinal fluid (CSF) in children with hydrocephalus. Ventriculoatrial and ventriculopleural shunting are alternative methods of CSF drainage, which have gained less acceptance. Ventriculopleural shunts are seldom used owing to justified fears of pneumothorax and symptomatic effusions of CSF. The addition of an antisiphon device to standard shunt systems seems to have prevented CSF pleural effusion. From 1988 to 1998, we treated each of six hydrocephalic children with a ventriculopleural shunt. In five cases we used new-technology valves designed to prevent the effects of siphoning with current differential pressure valves. Peritoneal adhesions, recent peritonitis, ascites, and obstruction of a previous ventriculoatrial shunt were the indications for pleural shunting. After a mean follow-up period of 2.5 years all shunts were functioning adequately. Only one patient showed transient symptoms of CSF overdrainage, which were corrected by up-grading the valve setting with the magnet. A late death was unrelated to the pleural shunting procedure. The use of valves of a new design designed to prevent overdrainage seems to account for the satisfactory outcomes observed in this series. We suggest that ventriculopleural shunting should be considered as the preferred alternative to peritoneal drainage in children with intra-abdominal adhesions or with a history of recent peritoneal infection.

  9. Ventriculoperitoneal shunt perforations of the gastrointestinal tract.

    Science.gov (United States)

    Thiong'o, Grace Muthoni; Luzzio, Christopher; Albright, A Leland

    2015-07-01

    OBJECT The purposes of this study were to evaluate the frequency with which children presented with ventriculoperitoneal (VP) shunt perforations of the gastrointestinal (GI) tract, to determine the type of shunts that caused the perforations, and to compare the stiffness of perforating catheters with the stiffness of catheters from other manufacturers. METHODS Medical records were reviewed of 197 children who were admitted with VP shunt malfunction. Catheter stiffness was evaluated by measuring relative resistance to cross-sectional compression, resistance to column buckling, and elasticity in longitudinal bending. Catheter frictional force was measured per unit length. RESULTS Six children were identified whose VP shunts had perforated the GI tract; 2 shunts subsequently protruded through the anal orifice, 1 protruded through the oral cavity, and 3 presented with subcutaneous abscesses that tracked upward from the intestine to the chest. All perforating shunts were Chhabra shunts. Catheter stiffness and resistance to bending were greatest with a Medtronic shunt catheter, intermediate with a Codman catheter, and least with a Chhabra catheter. Frictional force was greatest with a Chhabra catheter and least with a Medtronic catheter. CONCLUSIONS The frequency of perforations by Chhabra shunts appears to be higher than the frequency associated with other shunts. The increased frequency does not correlate with their stiffness but may reflect their greater frictional forces.

  10. Hydrocephalus and Ventriculoperitoneal Shunts: Modes of Failure and Opportunities for Improvement.

    Science.gov (United States)

    Jorgensen, Julianne; Williams, Corin; Sarang-Sieminski, Alisha

    2016-01-01

    Between 0.5 and 4 of every 1000 children are born with hydrocephalus. Hydrocephalus is an over-accumulation of cerebrospinal fluid (CSF) in the ventricles of the brain, which can affect cognitive function, vision, appetite, and cranial nerve function. Left untreated, hydrocephalus can result in death. The current treatment for hydrocephalus uses ventriculoperitoneal (VP) shunts with valves to redirect CSF from the ventricles into the peritoneum. Shunt technology is limited by a number of complications, which include infection after implantation, shunt obstruction due to clot formation or catheter obstruction by scar tissue or choroid plexus, disconnection and tubing migration, and overdrainage or underdrainage of CSF due to valve malfunction. While modifications to surgical procedures and shunt design have been introduced, only modest improvements in outcomes have been observed. Here we provide an overview of hydrocephalus, VP shunts, and their modes of failure, and we identify numerous areas of opportunity for biomedical engineers and physicians to collaborate to improve the performance of VP shunts.

  11. Bucket and straw technique to facilitate passage of a ventriculoperitoneal shunt through the distal tunneling sheath.

    Science.gov (United States)

    Downes, Angela E; Vandergrift, William A; Beckman, Joshua M; Truong, Devon; Tuite, Gerald F

    2014-12-01

    Placement of a ventriculoperitoneal shunt (VPS) is a procedure comprising many small steps. Difficulties and delays can arise when passing the distal shunt tubing down the distal tunneling sheath during surgery. The authors of this report describe a simple technique for quickly passing the distal catheter of a VPS through the tunneler sheath, whereby the sheath is used as a fluid tube to allow the distal catheter to be drawn through the fluid tube under suction pressure. The plastic sheath that surrounds the shunt tunneler device is used as a fluid tube, or "straw," with the proximal aperture submerged into a bucket of sterile irrigation liquid containing the distal catheter. Suction pressure is placed against the distal aperture of the tunneler, and the shunt catheter is quickly drawn through the sheath. No special equipment is required. In time trials, the bucket and straw technique took an average of 0.43 seconds, whereas traditional passage methods took 32.3 seconds. The "bucket and straw" method for passing distal shunt tubing through the tunneler sheath is a technique that increases surgical efficiency and reduces manual contact with shunt hardware.

  12. Shunt for bypass graft of the cavernous carotid artery: an anatomical and technical study.

    Science.gov (United States)

    al-Mefty, O; Khalil, N; Elwany, M N; Smith, R R

    1990-11-01

    During direct surgery of neoplastic and vascular lesions of the cavernous sinus, the intracavernous carotid artery may be injured beyond repair, or its total isolation may be necessary for surgical management of these lesions. The newly developed procedure of a saphenous vein graft bypass of the cavernous carotid artery allows re-establishment of carotid circulation. Patients with poor collateral circulation are at high risk for ischemic complications induced by the prolonged temporary occlusion required to perform the bypass graft. Optimal management of these patients is to perform the venous bypass graft for permanent vascularization while maintaining carotid cerebral circulation through an intraoperative shunt. We studied this procedure in cadavers, and three shunt types were evaluated: the external intrapetrous-supraclinoid shunt (Type A), the internal intrapetrous-supraclinoid shunt (Type B), and the neck internal carotid-supraclinoid shunt (Type C). Anatomical landmarks, techniques, distances, caliber, and materials used are presented. The rationale and candidates for such a procedure are discussed. The specifications of an optimal balloon shunt are presented, and the three procedures are compared.

  13. Atypical inguinal malignant peripheral nerve sheath tumour with arteriovenous fistula of the left femoral nerve in a child

    Energy Technology Data Exchange (ETDEWEB)

    Melloni, Pietro; Veintemillas, Maite [Corporacio Sanitaria Parc Tauli, Unitat de Diagnostic per Imatge d' Alta Tecnologia, Barcelona (Spain); Olsina, Gustavo; Oliva, Eulalia; Garcia-Continente, Gemma [Capio Hospital General de Catalunya, Servei de Diagnostic per la Imatge, Barcelona (Spain); Garcia-Hernandez, Felip [Capio Hospital General de Catalunya, Servei de Anatomia Patalogica, Barcelona (Spain)

    2008-07-15

    We report a 9-year-old girl who developed a malignant peripheral nerve sheath tumour (MPNST) with an arteriovenous fistula arising from the left femoral nerve and adjacent to the iliofemoral vessels in the ipsilateral groin, but without infiltrating them. We describe the MRI and MRA findings. Although MPNST is relatively well known and widely studied, the location of this mass is unique in a child. The mass was surgically removed. (orig.)

  14. Minimally invasive ventriculo-atrial shunt for hydrocephalus

    Institute of Scientific and Technical Information of China (English)

    李江山; 江勇豪; 程成; 张世凯

    2005-01-01

    Objective: To study the therapeutic effect of mini-traumatic ventriculo-atrial shunt on hydrocephalus. Methods: Seventeen patients were treated with right internal jugular venepuncture intubation to finish minimally invasive ventriculo-atrial shunt for hydrocephalus. The patients were evaluated by CT/MRI. The catheters were deployed at the proper position in the right atrium under X-ray fluoroscopy.Results: The hydrocephalus in all the 17 patients eliminated with this surgical procedure with a 100% success rate technically. The operational duration ranged from 0.75 to 1.5 h (average: 1 h). Mistaken puncture into the internal carotid artery as a complication occurred on 1 case.Conclusions: The mini-traumatic ventriculo-atrial shunt, as a novel minimal invasion technique, has the advantages of small trauma, no influence on local blood circulation, short time and simplicity at operation, rapid healing, and good short-term effect. Moreover, it is suitable for those patients with organic dysfunction.

  15. A wireless monitoring system for Hydrocephalus shunts.

    Science.gov (United States)

    Narayanaswamy, A; Nourani, M; Tamil, L; Bianco, S

    2015-08-01

    Patients with Hydrocephalus are usually treated by diverting the excess Cerebrospinal Fluid (CSF) to other parts of the body using shunts. More than 40 percentage of shunts implanted fail within the first two years. Obstruction in the shunts is one of the major causes of failure (45 percent) and the detection of obstruction reduces the complexity of the revision surgery. This paper describes a proposed wireless monitoring system for clog detection and flow measurement in shunts. A prototype was built using multiple pressure sensors along the shunt catheters for sensing the location of clog and flow rate. Regular monitoring of flow rates can be used to adjust the valve in the shunt to prevent over drainage or under drainage of CSF. The accuracy of the flow measurement is more than 90 percent.

  16. Rapid resolution of an acute subdural hematoma by increasing the shunt valve pressure in a 63-year-old man with normal-pressure hydrocephalus with a ventriculoperitoneal shunt: a case report and literature review

    Directory of Open Access Journals (Sweden)

    Hayes Jackson

    2012-11-01

    Full Text Available Abstract Introduction Symptomatic subdural hematoma development is a constant concern for patients who have undergone cerebrospinal fluid shunting procedures to relieve symptoms related to normal-pressure hydrocephalus. Acute subdural hematomas are of particular concern in these patients as even minor head trauma may result in subdural hematoma formation. The presence of a ventricular shunt facilitates further expansion of the subdural hematoma and often necessitates surgical treatment, including subdural hematoma evacuation and shunt ligation. Case presentation We present the case of a 63-year-old North American Caucasian man with normal-pressure hydrocephalus with an adjustable valve ventriculoperitoneal shunt who developed an acute subdural hematoma after sustaining head trauma. Conservative treatment was favored over operative evacuation because our patient was neurologically intact, but simple observation was considered to be too high risk in the setting of a low-pressure ventriculoperitoneal shunt. Thus, the valve setting on the ventriculoperitoneal shunt was increased to its maximum pressure setting in order to reduce flow through the shunt and to mildly increase intracranial pressure in an attempt to tamponade any active bleeding and limit hematoma expansion. A repeat computed tomography scan of the head six days after the valve adjustment revealed complete resolution of the acute subdural hematoma. At this time, the valve pressure was reduced to its original setting to treat symptoms of normal-pressure hydrocephalus. Conclusions Programmable shunt valves afford the option for non-operative management of acute subdural hematoma in patients with ventricular shunts for normal-pressure hydrocephalus. As illustrated in this case report, increasing the shunt valve pressure may result in rapid resolution of the acute subdural hematoma in some patients.

  17. Arteriovenous Malformation Detected by Small Bowel Endoscopy

    Directory of Open Access Journals (Sweden)

    Takaaki Fujii

    2014-10-01

    Full Text Available Gastrointestinal bleeding that originates in the small intestine is often difficult to diagnose. When successful diagnosis reveals a lesion that can be localized preoperatively, the laparoscopic approach is an appropriate and beneficial treatment modality for small bowel resection. A 69-year-old man presented with a 6-month history of gastrointestinal bleeding and symptomatic transfusion-dependent anemia. Upper and lower endoscopy were normal. Double-balloon endoscopy established the source of the bleeding as a 0.5-cm polypoid mass appearing as a submucosal tumor with redness and pulsation in the lower ileum, suggesting a vascular lesion. Laparoscopic small bowel resection was successful in removing the mass in the ileum. Histological evaluation of the mass revealed an arteriovenous malformation. Preoperative small bowel endoscopy can be useful for diagnosing the cause and localization of arteriovenous malformation in the small intestine.

  18. Lumboperitoneal shunts: Review of 409 cases

    Directory of Open Access Journals (Sweden)

    Yadav Y

    2004-04-01

    Full Text Available BACKGROUND AND AIMS: A prospective study was carried out to evaluate the lumboperitoneal shunt procedure. MATERIAL AND METHODS: Four hundred and nine patients having communicating hydrocephalus were selected for the procedure during a 10-year period from March 1992 to February 2002. The average follow-up was 45.34 months. RESULTS: Tubercular meningitis (TBM-related hydrocephalus was detected in 285 patients. Forty per cent of the patients were less than 15 years of age. Glasgow Coma Scale (GCS of less than 8 was seen in 40% patients and 14.9% patients were in GCS 13-15. At the time of discharge 56.7% patients improved in their GCS to 13 -15 and 14.9% were in GCS 8 or less. The overall mortality was 5.13% and shunt-related mortality was seen in 2% patients. Shunt malfunction requiring revision was seen in 32 patients (7.8% and the total number of shunt revisions was 44 (11%. Shunt infection was noted in 3.4% patients. CSF leak at the lumbar end occurred in 12 patients. Four patients required conversion of LP shunt to VP shunt. CONCLUSIONS: Lumboperitoneal shunt is an effective shunting procedure in communicating hydrocephalus.

  19. Diagnosis and evaluation of intracranial arteriovenous malformations

    OpenAIRE

    Andrew Conger; Charles Kulwin; Lawton, Michael T; Cohen-Gadol, Aaron A.

    2015-01-01

    Background: Ideal management of intracranial arteriovenous malformations (AVMs) remains poorly defined. Decisions regarding management of AVMs are based on the expected natural history of the lesion and risk prediction for peritreatment morbidity. Microsurgical resection, stereotactic radiosurgery, and endovascular embolization alone or in combination are all viable treatment options, each with different risks. The authors attempt to clarify the existing literature′s understanding of the natu...

  20. Gamma Knife treatment for cerebral arteriovenous malformations.

    Science.gov (United States)

    Kemeny, Andras A; Radatz, Matthias W R; Rowe, Jeremy G; Walton, Lee; Vaughan, Paul

    2007-01-01

    One of the earliest indications for Gamma Knife treatment, radiosurgery for cerebral arteriovenous malformations, has stood the test of time. While initially only the ideal cases (small, compact nidus in a non-eloquent site) were chosen, increasingly larger, more complex AVMs were treated. Combination treatment with embolisation and surgery enables most lesions to be treated with success and remarkably low complication rate. This paper is a brief overview of the experience gained in Sheffield.

  1. Subarachnoid hemorrhage and intracereebral hematoma following lumboperitoneal shunt for pseudotumor cerebri : a rare complication.

    Directory of Open Access Journals (Sweden)

    Suri A

    2002-10-01

    Full Text Available Placement of lumboperitoneal (LP shunt as a surgical treatment for benign intracranial hypertension (BIH is generally a safe procedure, with complications like mechanical failure, overdrainage and infections. Subarachnoid hemorrhage and intracerebral hematoma were seen after lumboperitoneal shunt in a patient having BIH. These complications were the cause of the patient′s deterioration. After removal of the hematoma and performing a decompressive procedure, patient′s neurological condition improved. The clinical features, investigations and clinical course are described and the literature reviewed.

  2. Unusual cause for ventriculoperitoneal shunt failure: Carcinoma breast compressing distal catheter

    Directory of Open Access Journals (Sweden)

    Roka Yam

    2010-01-01

    Full Text Available Insertion of a ventriculoperitoneal (VP shunt is one of the most common surgical procedures in any neurosurgery unit worldwide. Distal catheter obstruction outside the peritoneum is a rare cause of shunt failure. We report the first case of distal obstruction in a 70-year old female by carcinoma breast engulfing the catheter and causing kinking. Intraoperatively, the catheter was intratumoral with no flow of cerebrospinal fluid distally. She underwent relocation of a new catheter to the opposite side of the abdomen and modified mastectomy with resolution of the hydrocephalus. The postoperative course has been uneventful.

  3. Fístula arteriovenosa em crianças e adultos jovens Arteriovenous fistula in children and young adults

    Directory of Open Access Journals (Sweden)

    Marcio Lopes Miranda

    2000-12-01

    Full Text Available OBJETIVO: Com a introdução e o aprimoramento de técnicas para a realização de fístulas arteriovenosas (FAV em crianças, pacientes renais crônicos puderam iniciar tratamento com hemodiálise sem a necessidade de uso de shunts externos. MÉTODOS: Com o objetivo avaliar os resultados da confecção de fístulas arteriovenosas em crianças e adultos jovens de baixo peso e os fatores de risco relacionados. Foram levantados retrospectivamente os prontuários de 31 pacientes submetidos a 35 FAV, com idade variando de cinco a 24 anos, com peso entre 16 e 50kg. Os fatores de risco estudados foram hipertensão arterial, antecedentes de trombose, tendência à hipovolemia e presença de hipercolesterolemia. RESULTADOS: O índice de perda observado foi de 25% em pacientes com menos de 20kg e de 22,2% naqueles com mais de 20kg, resultados comparáveis aos da literatura. CONCLUSÕES: Observou-se que fístulas proximais não sofreram trombose; não houve relação entre a perda da FAV e os fatores de risco estudados e observou-se um índice de perda tardia de 23,5% nos pacientes que não estavam sendo submetidos à hemodiálise. Nos pacientes que utilizavam a FAV não se observou perda da mesma.BACKGROUND: Since the development of operative techniques for arteriovenous fistula (AVF creation, chronic hemodialysis for treatment of end-stage renal disease in children and young adults became an actual therapeutic option, obviating the need for external shunts. PURPOSE: To report our experience with surgically created AVF in 31 patients, aged 5 to 24 years old, relating long-term fistula patency with risk factors such as arterial hypertension, previous thrombosis events, tendency to hypovolemy, hypercholesterolemy, vein caliber and routine use of the fistula. RESULTS: Overall rate of fistula thrombosis was 22,8%, being 25% in patients weighing less than 20kg and 22,2% in those over 20kg. All fistulas performed on proximal arm veins were patent after 5 to 32

  4. A physical framework for implementing virtual models of intracranial pressure and cerebrospinal fluid dynamics in hydrocephalus shunt testing.

    Science.gov (United States)

    Venkataraman, Pranav; Browd, Samuel R; Lutz, Barry R

    2016-09-01

    OBJECTIVE The surgical placement of a shunt designed to resolve the brain's impaired ability to drain excess CSF is one of the most common treatments for hydrocephalus. The use of a dynamic testing platform is an important part of shunt testing that can faithfully reproduce the physiological environment of the implanted shunts. METHODS A simulation-based framework that serves as a proof of concept for enabling the application of virtual intracranial pressure (ICP) and CSF models to a physical shunt-testing system was engineered. This was achieved by designing hardware and software that enabled the application of dynamic model-driven inlet and outlet pressures to a shunt and the subsequent measurement of the resulting drainage rate. RESULTS A set of common physiological scenarios was simulated, including oscillations in ICP due to respiratory and cardiac cycles, changes in baseline ICP due to changes in patient posture, and transient ICP spikes caused by activities such as exercise, coughing, sneezing, and the Valsalva maneuver. The behavior of the Strata valve under a few of these physiological conditions is also demonstrated. CONCLUSIONS Testing shunts with dynamic ICP and CSF simulations can facilitate the optimization of shunts to be more failure resistant and better suited to patient physiology.

  5. Indication for shunt operation of normal pressure hydrocephalus. Combined assessment of infusion test and dynamic CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Jinnai, Takahiro; Nagao, Seigo [Kagawa Medical Univ., Miki (Japan); Kuyama, Hideyuki

    2000-03-01

    Normal pressure hydrocephalus (NPH) is one of the diseases that causes a neuro-surgically treatable form of dementia. Although patients with NPH can be treated with shunt operation, reliable indications for the surgery are not yet established. In this study, 20 NPH patients diagnosed by clinical symptoms were subjected to combined assessment by infusion test and dynamic CT scan, a useful diagnostic tool to select a shunt responsive cases. Patients were evaluated by measuring sequential changes in the density of the periventricular lucency (PVL) using dynamic CT scan and continuous lumbar subdural pressure monitoring during an infusion manometric test at a rate of 0.8 ml/min for 30 min. The average lumbar subdural pressure during infusion manometric test in the shunt responsive group was 18.4{+-}5.8 mmHg, which was significantly higher than that in the shunt non-responsive group which was 10.0{+-}4.0 mmHg (p<0.01). The relative changes in PVL density in the dynamic CT was also significantly higher in the shunt responsive group (0.99{+-}0.61 HU) compared to the shunt non-responsive group (0.15{+-}0.32) (p<0.01). Dynamic CT scan with infusion manometric test is useful in the selection of patients with NPH who are likely to respond to shunt surgery. (author)

  6. The effect of sevoflurane pretreatment or aftertreatment on intrapulmonary shunt for patients with one lung ventilation during thoracic surgical procedures%七氟烷预处理或后处理对胸外科手术单肺通气患者肺内分流的影响

    Institute of Scientific and Technical Information of China (English)

    张红芹; 王地萍; 黎平; 肖维; 徐璐

    2014-01-01

    目的:探讨七氟烷预处理或后处理对胸科手术单肺通气(OLV)患者肺内分流的影响。方法80例择期行开胸手术OLV的患者分为4组:全凭静脉组(P组),七氟烷预处理组(S1组),七氟烷后处理组(S2组),七氟烷全程吸入组(S3组),每组20例。在麻醉诱导前(T0)、OLV前(T1)即七氟烷预处理30 min后、OLV 30 min(T2)、OLV 60 min(T3)、OLV结束前(T4)、OLV结束后30 min(T5)采集桡动脉及右心房血样行血气分析,计算肺内分流率(Qs/Qt),同时记录血流动力学指标及相关的临床数据。结果 OLV期间,4组患者氧分压较双肺通气时明显降低(P<0.05),但4组间的氧分压比较差异无统计学意义(P>0.05);4组患者的肺内分流较双肺通气时明显增加( P<0.05),但S1、S2、S3组的肺内分流较P组低( P<0.05),S1、S2、S3组间差异无统计学意义(P>0.05)。结论七氟烷预处理、后处理全程处理能降低OLV患者肺内分流,但3种处理方式之间无显著差异,也不能明显提高动脉氧分压。%Objective To study the effect of sevoflurane pretreatment or aftertreatment on intrapulmonary shunt for patients with one lung ventilation(OLV)during thoracic surgical procedures .Methods 80 ASA I or II patients underwent thoracic surgery with OLV were randomly divided into four groups(n= 20 for each):(1)Propofol group(group P);(2)Sevoflurane pretreatment group(group S1);(3)Sevoflurane aftertreatment group(group S2);(3)Sevoflurane whole-treatment group(group S3) .Blood sam-ples were taken from radial artery and right atrial blood before induction of anesthesia(baseline T .0) ,before OLV(sevoflurane pre-treatment 30 min ,T1) ,after OLV 30 ,60 min and before the end of OLV(T2-T4)and after the end of OLV(T5)for measurement of blood gases and calculation of Qs/Qt .The indexs of hemodynamics and relative clinical data were recorded .Results

  7. Congenital Portosystemic Shunt: Our Experience

    Directory of Open Access Journals (Sweden)

    Tiziana Timpanaro

    2015-01-01

    Full Text Available Introduction. Congenital portosystemic venous malformations are rare abnormalities in which the portal blood drains into a systemic vein and which are characterized by extreme clinical variability. Case Presentations. The authors present two case reports of a congenital extrahepatic portosystemic shunt (Type II. In the first patient, apparently nonspecific symptoms, such as headache and fatigue, proved to be secondary to hypoglycemic episodes related to the presence of a portosystemic shunt, later confirmed on imaging. During portal vein angiography, endovascular embolization of the portocaval fistula achieved occlusion of the anomalous venous tract. In the second patient, affected by Down’s syndrome, the diagnosis of a portosystemic malformation was made by routine ultrasonography, performed to rule out concurrent congenital anomalies. Because of the absence of symptoms, we chose to observe this patient. Conclusions. These two case reports demonstrate the clinical heterogeneity of this malformation and the need for a multidisciplinary approach. As part of a proper workup, clinical evaluation must always be followed by radiographic diagnosis.

  8. In vitro hydrodynamic properties of the Miethke proGAV hydrocephalus shunt

    Directory of Open Access Journals (Sweden)

    Richards Hugh K

    2006-06-01

    Full Text Available Abstract Background Adjustable shunts are very popular in the management of hydrocephalus and are believed to help in minimizing the number of surgical revisions. The drawback with almost all constructions is that they may be accidentally readjusted in relatively weak magnetic fields (around 30–40 mTesla Materials and methods The ProGav Miethke shunt is composed of an adjustable ballon-spring valve unit and an integrated over-drainage compensating gravitational device (known as the shunt assistant. A mechanical 'brake' is intended to prevent changes to the valve's performance level in a strong magnetic field. We evaluated the performance and hydrodynamic properties of a sample of three valves in the UK Shunt Evaluation Laboratory. Results All the shunts showed good mechanical durability over the three-month period of testing, and good stability of hydrodynamic performance over a one-month period The pressure-flow performance curves, operating, opening and closing pressures fell within the limits specified by the manufacturer, and changed according to the programmed performance levels. The operating pressure increased when the shunt assistant was in the vertical position, as specified. The valve has a low hydrodynamic resistance (0.53 mm mmHg ml-1 min-1. External programming proved to be easy and reliable. Strong magnetic fields from a 3 Tesla MR scanner were not able to change the programming of the valve. Conclusion The ProGAV shunt is an adjustable, low resistance valve that is able to limit posture-related over-drainage. Unlike other adjustable valves, the ProGAV cannot be accidentally re-adjusted by external magnetic field such as a 3T MR scanner.

  9. Decompensated porto-pulmonary hypertension in a cirrhotic patient with thrombosis of portocaval shunt

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    We report a case of decompensated porto-pulmonary hypertension closely associated with the development of intra-portocaval shunt thrombosis. A woman with Laennec's cirrhosis was hospitalized because of severe dyspnea and edema. She underwent surgical portocaval anastomosis ten years ago. Imaging studies showed massive intra-shunt thrombosis, portal hypertension, ascites, pleuro-pericardial effusions and enlargement of right cardiac cavities. Cardiac catheterization allowed to rule out coronary and leftsided heart abnormalities and led to the diagnosis of pre-capillary pulmonary hypertension. Antithrombotic treatment with low molecular weight heparin was instituted. The management also included ACE inhibitors,spironolactone, low-salt diet and lactulose. The patient was discharged and three months later we observed the disappearance of edema, ascites and pleuropericardial effusions, a marked body weight reduction and improved dyspnea and liver function tests. A possible link between the development of intra-shunt thrombosis and clinical decompensation in our patient was hypothesized. In fact, it has been demonstrated that the increased portal pressure, caused by occlusion of portosystemic shunt, reduces renal plasma flow and increases systemic endothelin-1 concentration. In our patient the disappearance of edematous state and improved dyspnea observed after recanalization of the shunt strongly support this hypothesis.

  10. Successful laparoscopic bipolar coagulation of a large arteriovenous malformation due to invasive trophoblastic disease: a case report.

    Science.gov (United States)

    Corusic, Ante; Barisic, Dubravko; Lovric, Helena; Despot, Albert; Planinic, Pavao

    2009-01-01

    We report the case of an acquired large arteriovenous malformation due to invasive gestational trophoblastic tumor that was treated successfully with laparoscopic surgery. After 4 cycles of methotrexate chemotherapy, a vascular tangle (volume, 28 cm(3)) was noted that emerged from the right uterine horn, invading the broad ligament adjacent to the uterine artery. Doppler ultrasonography along with magnetic resonance arteriography confirmed the diagnosis. The location, size and relation of this arteriovenous malformation to the uterine vasculature demanded urgent intervention. Laparoscopy was performed, and bipolar coagulation of the ovarian and uterine artery feeding branches was achieved after surgical resection of the tumor. The defect in the uterine wall with an intact uterine cavity was reconstructed using sutures. There were no intraoperative or postoperative complications. The patient underwent chemotherapy, and at 2-month follow-up was cured and has since had regular menstrual cycles.

  11. Outcome of endoscopic third ventriculostomy and Chhabra shunt system in noncommunicating non-tumor childhood hydrocephalus

    Directory of Open Access Journals (Sweden)

    O E Idowu

    2009-01-01

    Full Text Available Background : Endoscopic third ventriculostomy (ETV the main alternative to ventriculoperitoneal shunt (VPS is just beginning to have a foothold in West Africa. It provides a great opportunity for a hydrocephalic child to be shunt free. The purpose of this paper is to compare outcome following ETV and VPS (using the cheap Chhabra shunt in children with noncommunicating non-tumoral hydrocephalus in an environment where late presentation is the norm. Materials and Methods : Sixty-three pediatric patients (< 6 years with hydrocephalus who underwent a VPS or ETV at our hospital were included in this study. The study period was of 30 months (January 2006 till June 2008. Clinically successful outcome was defined as no event occurring during or after surgery that resulted in an alternate surgical procedure, or significant post-operative complication that includes death. All complications related to the procedures were also analyzed. Results : The outcome of surgical intervention was not significantly related to the gender, age of the patient at surgery, or type of surgery. The post-operative complication rate was similar in both groups. Conclusions : The clinical outcome of ETV is comparable to that of VPS, with the added benefit of no shunt-related problems; and being a short procedure, patient anesthesia and operation time, hospital stay, and cost are significantly reduced. We consider ETV to be the procedure of choice for the treatment of noncommunicating nontumoral hydrocephalus in the pediatric population.

  12. EFFECT OF HEPARIN ON THE PATENCY OF ARTERIOVENOUS FISTULA

    Directory of Open Access Journals (Sweden)

    H Ravari

    2008-11-01

    Full Text Available "nPatients with end stage renal disease need a good vascular access for hemodialysis. Arteriovenous fistula is the method of choice for vascular access in these patients. However, failure of arteriovenous fistula due to thrombosis is a major problem. The aim of this study was to evaluate the effect of the heparin on the patency of the arteriovenous fistula. This prospective interventional case control study was performed from November 2003 through May 2005 in vascular surgery ward in Imam Reza Hospital. All the patients who underwent a surgery in order to perform an arteriovenous fistula in cubital or snuff box areas for the dialysis means were enrolled. They were randomly divided into two groups. The case group (n = 96 received intraoperative heparin whereas the controls (n = 102 did not. Early observation of arteriovenous fistula (immediately after surgery showed patency in 89% of heparin group and in 87% of the control group. The patency rate 2 weeks after the surgery was 85% in heparin group versus 74% in the control group, resulting in a statistically significant difference (P value = 0.046. According to higher patency rate of arteriovenous fistula in 2 weeks following surgery in case group, we recommend intraoperative use of heparin in arteriovenous fistula operations.

  13. Preoperative shunts in thalamic tumours.

    Directory of Open Access Journals (Sweden)

    Goel A

    2000-10-01

    Full Text Available Thirty one patients with thalamic glioma underwent a pre-tumour resection shunt surgery. The procedure was uneventful in 23 patients with relief from symptoms of increased intracranial pressure. Eight patients worsened after the procedure. The level of sensorium worsened from excessively drowsy state to unconsciousness in seven patients. Three patients developed hemiparesis, 4 developed paresis of extra-ocular muscles and altered pupillary reflexes, and 1 developed incontinence of urine and persistent vomiting. Alteration in the delicately balanced intracranial pressure and movements in the tumour and vital adjacent brain areas could be the probable cause of the worsening in the neurological state in these 8 patients. On the basis of these observations and on review of literature, it is postulated that the ventricular dilatation following an obstruction in the path of the cerebrospinal fluid flow by a tumour could be a natural defense phenomenon of the brain.

  14. [Arteriovenous malformation-glioma association: study of four cases].

    Science.gov (United States)

    Borges, Lia Raquel R; Malheiros, Suzana M F; Pelaez, Maria Paula; Stávale, João Norberto; Santos, Adrialdo J; Carrete, Henrique; Nogueira, Roberto Gomes; Ferraz, Fernando A P; Gabbai, Alberto A

    2003-06-01

    We reviewed the clinical presentation, imaging and histopathologic findings in 4 patients with the diagnosis of arteriovenous malformation associated with glioma that were operated on from 1991 to 2000 in our institution. Four patients (2 males; age between 15 and 52 years) presented with progressive headache with clinical evidence of intracranial hypertension (in 3) and partial seizures (in 1). CT scan showed a brain tumor without any detectable pathologic vessels. Histologic examination revealed astrocytic tumors associated with arteriovenous malformation. No patient presented the vascular component intermixed with the tumor. The arteriovenous-glioma association is rare and must be identified by a clear demarcation between the malformation and the tumor.

  15. Anaesthetic management of a child with massive extracranial arteriovenous malformation

    Directory of Open Access Journals (Sweden)

    Faisal Shamim

    2012-01-01

    Full Text Available Vascular tumors affect the head and neck commonly but arteriovenous malformations are rare. Vascular malformations are often present at birth and grow with the patient, usually only becoming significant later in childhood. Embolization has been the mainstay of treatment in massive and complex arteriovenous malformations. We present a case of massive extracranial arteriovenous malformation in a 7-year-old boy causing significant workload on right heart and respiratory distress. The management of angioembolization under general anaesthesia and anaesthetic concerns are presented.

  16. CSF ascites : a rare complication of ventriculoperitoneal shunt surgery.

    Directory of Open Access Journals (Sweden)

    Chidambaram B

    2000-10-01

    Full Text Available CSF ascites is a very rare complication of ventriculoperitoneal (VP shunt procedure. No definite explanation has been offered for the inability of the peritoneum to absorb the CSF. Two children who underwent VP shunting for hydrocephalus, presented with ascites 3 (1/2 years and 4 months respectively, after the shunt was placed. The treatment of choice is conversion of the VP shunt to a ventriculoatrial shunt.

  17. Idiopathic intracranial hypertension: lumboperitoneal shunts versus ventriculoperitoneal shunts--case series and literature review.

    LENUS (Irish Health Repository)

    Abubaker, Khalid

    2012-02-01

    OBJECTIVES: Idiopathic intracranial hypertension (IIH) is an uncommon but important cause of headache that can lead to visual loss. This study was undertaken to review our experience in the treatment of IIH by neuronavigation-assisted ventriculoperitoneal (VP) shunts with programmable valves as compared to lumboperitoneal (LP) shunts. METHODS: A retrospective chart review was conducted on 25 patients treated for IIH between 2001 and 2009. Age, sex, clinical presentation, methods of treatment and failure rates were recorded. RESULTS: Seventy-two per cent were treated initially with LP shunts. Failure rate was 11% in this group. Neuronavigation-assisted VP shunts were used to treat 28%. In this group, the failure rate was 14%. CONCLUSION: Our experience indicates that both LP shunts and VP shuts are effective in controlling all the clinical manifestations of IIH in the immediate postoperative period. Failure rates are slightly higher for VP shunts (14%) than LP shunts (11%). However, revision rates are higher with LP shunts (60%) than with VP shunts (30%).

  18. Flow-regulated versus differential pressure-regulated shunt valves for adult patients with normal pressure hydrocephalus

    DEFF Research Database (Denmark)

    Ziebell, Morten; Wetterslev, Jørn; Tisell, Magnus

    2013-01-01

    Since 1965 many ventriculo-peritoneal shunt systems have been inserted worldwide to treat hydrocephalus. The most frequent indication in adults is normal pressure hydrocephalus (NPH), a condition that can be difficult to diagnose precisely. Surgical intervention with flow-regulated and differential...

  19. Abortion - surgical

    Science.gov (United States)

    Suction curettage; Surgical abortion; Elective abortion - surgical; Therapeutic abortion - surgical ... Surgical abortion involves dilating the opening to the uterus (cervix) and placing a small suction tube into the uterus. ...

  20. Congenital portosystemic shunts with and without gastrointestinal bleeding - case series

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Ying; Chen, Jun; Chen, Qi; Ji, Min; Pa, Mier; Qiao, Zhongwei [Children' s Hospital of Fudan University, Department of Radiology, Shanghai (China); Zhu, Hui [Fudan University Shanghai Cancer Center, Department of Radiology, Shanghai (China); Zheng, Shan [Children' s Hospital of Fudan University, Department of Surgery, Shanghai (China)

    2015-12-15

    The clinical presentation of congenital portosystemic shunt is variable and gastrointestinal bleeding is an uncommon presentation. To describe the imaging features of congenital portosystemic shunt as it presented in 11 children with (n = 6) and without gastrointestinal bleeding (n = 5). We performed a retrospective study on a clinical and imaging dataset of 11 children diagnosed with congenital portosystemic shunt. A total of 11 children with congenital portosystemic shunt were included in this study, 7 with extrahepatic portosystemic shunts and 4 with intrahepatic portosystemic shunts. Six patients with gastrointestinal bleeding had an extrahepatic portosystemic shunt, and the imaging results showed that the shunts originated from the splenomesenteric junction (n = 5) or splenic vein (n = 1) and connected to the internal iliac vein. Among the five cases of congenital portosystemic shunt without gastrointestinal bleeding, one case was an extrahepatic portosystemic shunt and the other four were intrahepatic portosystemic shunts. Most congenital portosystemic shunt patients with gastrointestinal bleeding had a shunt that drained portal blood into the iliac vein via an inferior mesenteric vein. This type of shunt was uncommon, but the concomitant rate of gastrointestinal bleeding with this type of shunt was high. (orig.)

  1. Resonant Electromagnetic Shunt Damping of Flexible Structures

    DEFF Research Database (Denmark)

    Høgsberg, Jan Becker

    2016-01-01

    Electromagnetic transducers convert mechanical energy to electrical energy and vice versa. Effective passive vibration damping of flexible structures can therefore be introduced by shunting with an accurately calibrated resonant electrical network thatcontains a capacitor to create the desired...

  2. Temporary intravascular shunts for peripheral vascular trauma.

    Directory of Open Access Journals (Sweden)

    Husain A

    1992-04-01

    Full Text Available Polyvinylchloride (PVC disposable endotracheal suction catheters were successfully used as temporary intravascular shunts in 5 patients of popliteal artery trauma. These simple shunts should be used routinely in such conditions to immediately re-establish blood supply to the ischaemic limb particularly in patients of polytrauma where systemic anticoagulation is contraindicated. This avoids the inherent delay prior to vascular repair and reduces the incidence of irreversible ischemia.

  3. Syringoperitoneal shunt - a promising treatment in syringomyelia

    Energy Technology Data Exchange (ETDEWEB)

    Wester, K.; Midgard, R.; Kjosavik, I.F.

    1988-09-01

    Five patients with radiologically relatively pronounced multicystic syringomyelia were operated with an open, non-valved syringoperitoneal shunt. In the postoperative MRI scans there was an immediate and pronounced reduction of all cystic compartments, and within a few months the cysts had virtually disappeared. Two of the patients experienced marked neurological improvement. In one patient the shunt procedure led to additional moderate neurological deficits caused by postoperative rotation of the intrameduallary T-drain. For this reason straight intramedullary drains are now used.

  4. Aneurysmal portosystemic venous shunt: a case report.

    Science.gov (United States)

    Bodner, G; Glück, A; Springer, P; König, P; Perkmann, R

    1999-10-01

    A case of an aneurysmal portosystemic venous shunt detected by colour Doppler ultrasound (CDUS) is presented. A young female patient complained of postprandial fatigue and had paroxysmal tachycardia. A direct vascular communication between right portal vein and right hepatic vein was found at CDUS and confirmed by direct portal angiogram. Using detachable coils a complete occlusion of the intrahepatic shunt was obtained. Reports from the literature regarding portovenous aneurysms are reviewed.

  5. Ex-PRESS miniature glaucoma shunt in treatment of refractory glaucoma.

    Science.gov (United States)

    Kovačević, Suzana; Čanović, Samir; Didović, Ana; Kolega, Marija Škara; Bašić, Jadranka Katušić

    2015-03-01

    Refractory glaucoma in a complicated type of glaucoma of different ethyologies with one same characteristic--intraocular pressure of great resistance to therapy. There are different methods of treatment in such glaucomas, primary surgical options. Ex-PRESS miniature glaucoma shunt implantation was our treatment of choice. In our group of patients we achieved stabile intraocular pressure values in 4 month period of time with no serious or unexpected complications.

  6. Cell shunt resistance and photovoltaic module performance

    Energy Technology Data Exchange (ETDEWEB)

    McMahon, T.J.; Basso, T.S.; Rummel, S.R. [National Renewable Energy Lab., Golden, CO (United States)

    1996-05-01

    Shunt resistance of cells in photovoltaic modules can affect module power output and could indicate flawed manufacturing processes and reliability problems. The authors describe a two-terminal diagnostic method to directly measure the shunt resistance of individual cells in a series-connected module non-intrusively, without deencapsulation. Peak power efficiency vs. light intensity was measured on a 12-cell, series-connected, single crystalline module having relatively high cell shunt resistances. The module was remeasured with 0.5-, 1-, and 2-ohm resistors attached across each cell to simulate shunt resistances of several emerging technologies. Peak power efficiencies decreased dramatically at lower light levels. Using the PSpice circuit simulator, the authors verified that cell shunt and series resistances can indeed be responsible for the observed peak power efficiency vs. intensity behavior. The authors discuss the effect of basic cell diode parameters, i.e., shunt resistance, series resistance, and recombination losses, on PV module performance as a function of light intensity.

  7. Comparative study of lumboperitoneal shunt versus ventriculoperitoneal shunt in post meningitis communicating hydrocephalus in children

    Directory of Open Access Journals (Sweden)

    Amit Singh

    2013-01-01

    Full Text Available Background: Managing post meningitis hydrocephalus in children is a herculean task for the treating pediatric surgeon or neurosurgeon because of the morbidity associated with the disease per se and the complications of shunt surgery. By this study, the effectiveness of lumboperitoneal (LP shunt and ventriculoperitoneal (VP shunt in cases of post meningitis communicating hydrocephalus was assessed in children. Materials and Methods: This was a retrospective analysis of the records of children admitted in our institute between December 2005 and March 2008. Only children with post meningitis communicating hydrocephalus who underwent either LP or VP with a minimum follow-up period of 36 months were included in the study. Children with non-communicating hydrocephalus or hydrocephalus due to another etiology were excluded. Investigations were included plain brain computed tomography scan, air encephalography and X-ray skull. Medium pressure Chabbra shunt with slit valves was used in all cases of VP and LP shunt. A comparative analysis of the outcome was carried out between the two groups. Results: There were 66 males and 24 females (M: F 2.7:1. The average age at presentation was 40.3 months. LP shunt was performed in 37 while VP shunt in 53 cases Complication rate in the LP and VP shunt was 15% and 29% respectively with non-obstructed complications higher in VP group when compared to LP group. Obstructed complication rate was similar in both groups. Conclusion: Due to less morbidity and ease of placement, LP shunt can be an alternative to VP shunt in cases of communicating hydrocephalus in children, which has more non-obstructed complication rates as compared to LP shunt.

  8. Endovascular treatment for bilateral vertebral arteriovenous fistulas in neurofibromatosis 1.

    Science.gov (United States)

    Siddhartha, W; Chavhan, Govind B; Shrivastava, Manish; Limaye, Uday S

    2003-12-01

    We report a rare case of a 36-year-old woman with neurofibromatosis 1 (NF1) with bilateral vertebro-vertebral arteriovenous fistulas. The patient presented with quadriparesis and had neck pain. Angiography revealed vertebral arteriovenous fistulas bilaterally with dilated epidural venous plexuses compressing the cervical cord resulting in quadriparesis. Endovascular treatment using coils and balloons resulted in successful occlusion of both fistulas. At 6-months postembolization, the patient had improved significantly and is now able to walk with support.

  9. A case of a spontaneous intraorbital arteriovenous fistula: clinico-radiological findings and treatment by transvenous embolisation via the superior ophthalmic vein.

    Science.gov (United States)

    Naqvi, Jawad; Laitt, Roger; Leatherbarrow, Brian; Herwadkar, Amit

    2013-04-01

    A 72-year-old male presented with progressive right axial proptosis and red eye. Catheter angiography demonstrated an intraorbital arteriovenous fistula (IAVF) distal to the central retinal artery (CRA). Transvenous embolisation following direct surgical exposure of the superior ophthalmic vein (SOV) resulted in rapid resolution of his symptoms and signs. Transvenous embolisation via the SOV is a safe, effective alternative to transarterial embolisation for treating spontaneous IAVF where transarterial embolisation poses a risk of CRA occlusion.

  10. Idiopathic intracranial hypertension: lumboperitoneal shunts versus ventriculoperitoneal shunts--case series and literature review.

    LENUS (Irish Health Repository)

    Abubaker, Khalid

    2011-02-01

    Idiopathic intracranial hypertension (IIH) is an uncommon but important cause of headache that can lead to visual loss. This study was undertaken to review our experience in the treatment of IIH by neuronavigation-assisted ventriculoperitoneal (VP) shunts with programmable valves as compared to lumboperitoneal (LP) shunts.

  11. Outcome of cerebral arteriovenous malformations after linear accelerator reirradiation

    Science.gov (United States)

    Moraes, Paulo L.; Dias, Rodrigo S.; Weltman, Eduardo; Giordani, Adelmo J.; Benabou, Salomon; Segreto, Helena R. C.; Segreto, Roberto A.

    2015-01-01

    Background: The aim of this study was to evaluate the clinical outcome of patients undergoing single-dose reirradiation using the Linear Accelerator (LINAC) for brain arteriovenous malformations (AVM). Methods: A retrospective study of 37 patients with brain AVM undergoing LINAC reirradiation between April 2003 and November 2011 was carried out. Patient characteristics, for example, gender, age, use of medications, and comorbidities; disease characteristics, for example, Spetzler–Martin grading system, location, volume, modified Pollock–Flickinger score; and treatment characteristics, for example, embolization, prescription dose, radiation dose–volume curves, and conformity index were analyzed. During the follow-up period, imaging studies were performed to evaluate changes after treatment and AVM cure. Complications, such as edema, rupture of the blood–brain barrier, and radionecrosis were classified as symptomatic and asymptomatic. Results: Twenty-seven patients underwent angiogram after reirradiation and the percentage of angiographic occlusion was 55.5%. In three patients without obliteration, AVM shrinkage made it possible to perform surgical resection with a 2/3 cure rate. A reduction in AVM nidus volume greater than 50% after the first procedure was shown to be the most important predictor of obliteration. Another factor associated with AVM cure was a prescription dose higher than 15.5 Gy in the first radiosurgery. Two patients had permanent neurologic deficits. Factors correlated with complications were the prescription dose and maximum dose in the first procedure. Conclusion: This study suggests that single-dose reirradiation is safe and feasible in partially occluded AVM. Reirradiation may not benefit candidates whose prescribed dose was lower than 15.5 Gy in the first procedure and initial AVM nidus volume did not decrease by more than 50% before reirradiation. PMID:26110078

  12. Outcome of cerebral arteriovenous malformations after linear accelerator reirradiation

    Directory of Open Access Journals (Sweden)

    Paulo L Moraes

    2015-01-01

    Full Text Available Background: The aim of this study was to evaluate the clinical outcome of patients undergoing single-dose reirradiation using the Linear Accelerator (LINAC for brain arteriovenous malformations (AVM. Methods: A retrospective study of 37 patients with brain AVM undergoing LINAC reirradiation between April 2003 and November 2011 was carried out. Patient characteristics, for example, gender, age, use of medications, and comorbidities; disease characteristics, for example, Spetzler-Martin grading system, location, volume, modified Pollock-Flickinger score; and treatment characteristics, for example, embolization, prescription dose, radiation dose-volume curves, and conformity index were analyzed. During the follow-up period, imaging studies were performed to evaluate changes after treatment and AVM cure. Complications, such as edema, rupture of the blood-brain barrier, and radionecrosis were classified as symptomatic and asymptomatic. Results: Twenty-seven patients underwent angiogram after reirradiation and the percentage of angiographic occlusion was 55.5%. In three patients without obliteration, AVM shrinkage made it possible to perform surgical resection with a 2/3 cure rate. A reduction in AVM nidus volume greater than 50% after the first procedure was shown to be the most important predictor of obliteration. Another factor associated with AVM cure was a prescription dose higher than 15.5 Gy in the first radiosurgery. Two patients had permanent neurologic deficits. Factors correlated with complications were the prescription dose and maximum dose in the first procedure. Conclusion: This study suggests that single-dose reirradiation is safe and feasible in partially occluded AVM. Reirradiation may not benefit candidates whose prescribed dose was lower than 15.5 Gy in the first procedure and initial AVM nidus volume did not decrease by more than 50% before reirradiation.

  13. Ventriculoperitoneal shunt migration and coiling: A report of two cases

    Directory of Open Access Journals (Sweden)

    Shahram Shahsavaran

    2012-01-01

    Full Text Available Migration of the proximal and distal catheters of the ventriculoperitoneal shunt is a very rare event. Here, we report two infants with hydrocephalus and ventriculoperitoneal shunt who presented later with shunt coiling and migration. The first infant was admitted with scalp swelling around proximal incision 3 months after shunt insertion and migration and coiling of both ventricular and peritoneal catheters occurred under the scalp at that point. The second patient was referred 1 month after shunting with tense fontanel and vomiting. New brain imaging confirmed the whole shunt inside both lateral ventricles. The possible mechanisms causing this very uncommon complication and the management are explained.

  14. Endovascular management of dural arteriovenous fistulas of the transverse and sigmoid sinus in 150 patients

    Energy Technology Data Exchange (ETDEWEB)

    Kirsch, M. [Ernst-Moritz-Arndt-Universitaet Greifswald, Institut fuer Diagnostische Radiologie und Neuroradiologie, Greifswald (Germany); Liebig, T. [TU Muenchen, Institut fuer Neuroradiologie, Klinikum Rechts der Isar, Munich (Germany); Kuehne, D. [Klinik fuer Radiologie und Neuroradiologie, Alfried-Krupp-Krankenhaus, Essen (Germany); Henkes, H. [Katharinenhospital-Klinikum Stuttgart, Klinik fuer Neuroradiologie, Stuttgart (Germany)

    2009-07-15

    This study aimed to evaluate the safety and efficiency of the endovascular treatment of transverse-sigmoid sinus dural arteriovenous fistulas (TS{sub d}AVF). A total of 150 consecutive patients and 348 procedures were evaluated. Pulsatile tinnitus (81%), headache (15%), and intracranial hemorrhage (10%) were the most frequent manifestations of the TS{sub d}AVFs. More than half of the affected sinuses were partially or completely thrombosed. Access-wise treatment was performed transarterial (n = 33), transvenous (n = 21), or a combination thereof (n = 96). A mean of 2.4 procedures per patient was required. Immediate postprocedural occlusion rate after transarterial embolization was 30% only. Transvenous treatment alone resulted in an early occlusion rate of 81%, with delayed complete obliteration of half of the remaining fistulas. After combined transarterial/transvenous treatment, the angiographic cure rate was 54%. At follow-up, 88% of patients with residual shunt after the treatment showed complete occlusion. The cumulative complication rate was 9% (n = 13), with minor adverse events in ten patients (7%) and major complications in three patients (2%). Transvenous coil occlusion of the sinus segment with the adjacent dAVF site, eventually combined with transarterial occlusion of supplying arteries, is a very effective and well-tolerated treatment method. In selected patients, variations of these methods (e.g., sinus stenting, compartmental sinus occlusion) can be useful. (orig.)

  15. Dural Arteriovenous Fistula Following Translabyrinthine Resection of Cerebellopontine Angle Tumors: Report of Two Cases

    Science.gov (United States)

    Li, Peter M.M.C.; Fischbein, Nancy J.; Do, Huy M.; Blevins, Nikolas H.

    2011-01-01

    We describe two cases of dural arteriovenous fistula (DAVF) developing in a delayed fashion after translabyrinthine resection of cerebellopontine angle tumors. Two patients in an academic tertiary referral center, a 46-year-old woman and a 67-year-old man, underwent translabyrinthine resection of a 2-cm left vestibular schwannoma and a 4-cm left petrous meningioma, respectively. Both patients subsequently developed DAVF, and in each case the diagnosis was delayed despite serial imaging follow-up. In one patient, cerebrospinal fluid diversion before DAVF was identified as the cause of her intracranial hypertension; the other patient was essentially asymptomatic but with a high risk of hemorrhage due to progression of cortical venous drainage. Endovascular treatment was effective but required multiple sessions due to residual or recurrent fistulas. Dural arteriovenous fistula is a rare complication of translabyrinthine skull base surgery. Diagnosis requires a high index of clinical suspicion and an understanding of subtle imaging findings that may be present on follow-up studies performed for tumor surveillance. Failure to recognize this complication may lead to misguided interventions for treatment of hydrocephalus and other complications, as well as ongoing risks related to venous hypertension and intracranial hemorrhage. As this condition is generally curable with neurointerventional and/or surgical methods, timely diagnosis and treatment are essential. PMID:23984203

  16. External thoracic duct-venous shunt in conscious pigs for long term studies of connective tissue metabolites in lymph

    DEFF Research Database (Denmark)

    Jensen, L T; Olesen, H P; Risteli, J

    1990-01-01

    An experimental animal model for lymph studies is described. Thoracic duct-venous shunt was established in 12 pigs. Shunt patency averaged 5.5 days. The composition of connective tissue metabolites in lymph and serum were investigated during a standardized surgical operation (thoracotomy) under...... is a major route of tissue clearance for these components. The lymph/serum ratio of PICP was 1.0 in conscious pigs, indicating a direct release into the circulation. Total protein in lymph decreased (p less than 0.04) during surgery/anesthesia, whereas no changes were observed in serum. Pigs can be used...

  17. Direct Puncture Embolization of Scalp Arteriovenous Malformation in a Patient with Severe Hemophilia A: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kyung Mi; Kim, Eui Jong [Dept. of Radiology, Kyung Hee University Hospital, Kyung Hee University Graduate School of Medicine, Seoul (Korea, Republic of); Park, Bong Jin [Dept. of Neurosurgery, Kyung Hee University Hospital, Kyung Hee University Graduate School of Medicine, Seoul (Korea, Republic of); Kim, Keon Ha [Dept. of Radiology, Samsug Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2011-09-15

    We present a case of scalp arteriovenous malformation (AVM) in a patient with severe hemophilia A. The 22-year-old man presented with a pulsatile right parietal scalp mass. Digital subtraction angiography revealed an AVM in the right parietal scalp, supplied by superficial temporal and occipital arteries that drained into multiple venous structures. We successfully performed direct puncture embolization followed by surgical resection of the scalp AVM in conjunction with supplemental infusion of coagulation factor VIII before, during and after the embolization and the operation.

  18. Evaluation of hepatic steatosis in dogs with congenital portosystemic shunts using Oil Red O staining.

    Science.gov (United States)

    Hunt, G B; Luff, J A; Daniel, L; Van den Bergh, R

    2013-11-01

    The aims of this prospective study were to quantify steatosis in dogs with congenital portosystemic shunts (CPS) using a fat-specific stain, to compare the amount of steatosis in different lobes of the liver, and to evaluate intra- and interobserver variability in lipid point counting. Computer-assisted point counting of lipid droplets was undertaken following Oil Red O staining in 21 dogs with congenital portosystemic shunts and 9 control dogs. Dogs with congenital portosystemic shunts had significantly more small lipid droplets (dogs (P = .0013 and .0002, respectively). There was no significant difference in steatosis between liver lobes for either control dogs and CPS dogs. Significant differences were seen between observers for the number of large lipid droplets (>9 μ) and lipogranulomas per tissue point (P = .023 and .01, respectively). In conclusion, computer-assisted counting of lipid droplets following Oil Red O staining of liver biopsy samples allows objective measurement and detection of significant differences between dogs with CPS and normal dogs. This method will allow future evaluation of the relationship between different presentations of CPS (anatomy, age, breed) and lipidosis, as well as the impact of hepatic lipidosis on outcomes following surgical shunt attenuation.

  19. Alteration of brain viscoelasticity after shunt treatment in normal pressure hydrocephalus

    Energy Technology Data Exchange (ETDEWEB)

    Freimann, Florian Baptist; Sprung, Christian [Charite - University Medicine Berlin, Campus Virchow-Klinikum, Neurosurgical Department, Berlin (Germany); Streitberger, Kaspar-Josche; Klatt, Dieter; Sack, Ingolf [Charite - University Medicine Berlin, Campus Charite Mitte, Department of Radiology, Berlin (Germany); Lin, Kui; McLaughlin, Joyce [Rensselaer Polytechnic Institute, Mathematics Department, Troy, NY (United States); Braun, Juergen [Charite - University Medicine Campus Benjamin Franklin, Institute of Medical Informatics, Berlin (Germany)

    2012-03-15

    Normal pressure hydrocephalus (NPH) represents a chronic neurological disorder with increasing incidence. The symptoms of NPH may be relieved by surgically implanting a ventriculoperitoneal shunt to drain excess cerebrospinal fluid. However, the pathogenesis of NPH is not yet fully elucidated, and the clinical response of shunt treatment is hard to predict. According to current theories of NPH, altered mechanical properties of brain tissue seem to play an important role. Magnetic resonance elastography (MRE) is a unique method for measuring in vivo brain mechanics. In this study cerebral MRE was applied to test the viscoelastic properties of the brain in 20 patients with primary (N = 14) and secondary (N = 6) NPH prior and after (91 {+-} 16 days) shunt placement. Viscoelastic parameters were derived from the complex modulus according to the rheological springpot model. This model provided two independent parameters {mu} and {alpha}, related to the inherent rigidity and topology of the mechanical network of brain tissue. The viscoelastic parameters {mu} and {alpha} were found to be decreased with -25% and -10%, respectively, compared to age-matched controls (P < 0.001). Interestingly, {alpha} increased after shunt placement (P < 0.001) to almost normal values whereas {mu} remained symptomatically low. The results indicate the fundamental role of altered viscoelastic properties of brain tissue during disease progression and tissue repair in NPH. Clinical improvement in NPH is associated with an increasing complexity of the mechanical network whose inherent strength, however, remains degraded. (orig.)

  20. Analysis of postural sway in patients with normal pressure hydrocephalus: effects of shunt implantation

    Directory of Open Access Journals (Sweden)

    Czerwosz L

    2009-12-01

    Full Text Available Abstract Poor postural balance is one of the major risk factors for falling in normal pressure hydrocephalus (NPH. Postural instability in the clinic is commonly assessed based upon force platform posturography. In this study we focused on the identification of changes in sway characteristics while standing quiet in patients with NPH before and after shunt implantation. Postural sway area and sway radius were analyzed in a group of 9 patients and 46 controls of both genders. Subject's spontaneous sway was recorded while standing quiet on a force platform for 30-60 s, with eyes open and then closed. Both analyzed sway descriptors identified between-group differences and also an effect of shunt implantation in the NPH group. Sway radius and sway area in patients exhibited very high values compared with those in the control group. Importantly, the effect of eyesight in patients was not observed before shunt implantation and reappeared after the surgical treatment. The study documents that static force platform posturography may be a reliable measure of postural control improvement due to shunt surgery.

  1. Analysis of postural sway in patients with normal pressure hydrocephalus: effects of shunt implantation.

    Science.gov (United States)

    Czerwosz, L; Szczepek, E; Blaszczyk, J W; Sokolowska, B; Dmitruk, K; Dudzinski, K; Jurkiewicz, J; Czernicki, Z

    2009-12-07

    Poor postural balance is one of the major risk factors for falling in normal pressure hydrocephalus (NPH). Postural instability in the clinic is commonly assessed based upon force platform posturography. In this study we focused on the identification of changes in sway characteristics while standing quiet in patients with NPH before and after shunt implantation. Postural sway area and sway radius were analyzed in a group of 9 patients and 46 controls of both genders. Subject's spontaneous sway was recorded while standing quiet on a force platform for 30-60 s, with eyes open and then closed. Both analyzed sway descriptors identified between-group differences and also an effect of shunt implantation in the NPH group. Sway radius and sway area in patients exhibited very high values compared with those in the control group. Importantly, the effect of eyesight in patients was not observed before shunt implantation and reappeared after the surgical treatment. The study documents that static force platform posturography may be a reliable measure of postural control improvement due to shunt surgery.

  2. Low-dose acetylsalicylic acid and bleeding risks with ventriculoperitoneal shunt placement.

    Science.gov (United States)

    Kamenova, Maria; Croci, Davide; Guzman, Raphael; Mariani, Luigi; Soleman, Jehuda

    2016-09-01

    OBJECTIVE Ventriculoperitoneal (VP) shunt placement is a common procedure for the treatment of hydrocephalus following diverse neurosurgical conditions. Most of the patients present with other comorbidities and receive antiplatelet therapy, usually acetylsalicylic acid (ASA). Despite its clinical relevance, the perioperative management of these patients has not been sufficiently investigated. The aim of this study was to compare the peri- and postoperative bleeding complication rates associated with ASA intake in patients undergoing VP shunt placement. METHODS Of 172 consecutive patients undergoing VP shunt placement between June 2009 and December 2015, 40 (23.3%) patients were receiving low-dose ASA treatment. The primary outcome measure was bleeding events in ASA users versus nonusers, whereas secondary outcome measures were postoperative cardiovascular events, hematological findings, morbidity, and mortality. A subgroup analysis was conducted in patients who discontinued ASA treatment for < 7 days (n = 4, ASA Group 1) and for ≥ 7 days (n = 36, ASA Group 2). RESULTS No statistically significant difference for bleeding events was observed between ASA users and nonusers (p = 0.30). Cardiovascular complications, surgical morbidity, and mortality did not differ significantly between the groups either. Moreover, there was no association between ASA discontinuation regimens (< 7 days and ≥ 7 days) and hemorrhagic events. CONCLUSIONS Given the lack of guidelines regarding perioperative management of neurosurgical patients with antiplatelet therapy, these findings elucidate one issue, showing comparable bleeding rates in ASA users and nonusers undergoing VP shunt placement.

  3. Simulation model for port shunting yards

    Science.gov (United States)

    Rusca, A.; Popa, M.; Rosca, E.; Rosca, M.; Dragu, V.; Rusca, F.

    2016-08-01

    Sea ports are important nodes in the supply chain, joining two high capacity transport modes: rail and maritime transport. The huge cargo flows transiting port requires high capacity construction and installation such as berths, large capacity cranes, respectively shunting yards. However, the port shunting yards specificity raises several problems such as: limited access since these are terminus stations for rail network, the in-output of large transit flows of cargo relatively to the scarcity of the departure/arrival of a ship, as well as limited land availability for implementing solutions to serve these flows. It is necessary to identify technological solutions that lead to an answer to these problems. The paper proposed a simulation model developed with ARENA computer simulation software suitable for shunting yards which serve sea ports with access to the rail network. Are investigates the principal aspects of shunting yards and adequate measures to increase their transit capacity. The operation capacity for shunting yards sub-system is assessed taking in consideration the required operating standards and the measure of performance (e.g. waiting time for freight wagons, number of railway line in station, storage area, etc.) of the railway station are computed. The conclusion and results, drawn from simulation, help transports and logistics specialists to test the proposals for improving the port management.

  4. Increased expression of osteopontin in brain arteriovenous malformations

    Institute of Scientific and Technical Information of China (English)

    XU Hong-zhi; QIN Zhi-yong; GU Yu-xiang; ZHOU Ping; XU Feng; CHEN Xian-cheng

    2012-01-01

    Background The precise mechanisms responsible for the development and growth of intracranial arteriovenous malformations (AVMs) remain unclear.Osteopontin (OPN) is a phosphorylated glycoprotein with diverse functions.This study aimed to analyze the expression of OPN in human brain AVMs.Methods The AVM nidus was surgically obtained from patients with AVM,whereas control brain artery specimens were surgically obtained from patients with epilepsy.Reverse transcription-polymerase chain reaction (RT-PCR) was used to examine the expression of OPN mRNA in biopsy specimens.OPN protein expression was localized by immunohistochemistry.The statistical differences between different groups were assessed by two-way analysis of variance (ANOVA).Results We analyzed 36 brain AVM specimens and 8 control brain artery specimens.Eleven patients with brain AVM received embolization treatment,and five underwent gamma knife radiotherapy before resection.Nineteen patients with brain AVM had a history of hemorrhage from AVMs.The expression of OPN mRNA was significantly higher in AVMs than that in the control specimens (25.76±2.71 vs.21.46±2.01,P <0.01).There was no statistically significant difference in the extent of OPN mRNA expression between the AVM group with and that without history of hemorrhage (26.13±2.45 vs.25.34±2.99) or gamma knife radiotherapy (24.39±2.10 vs.24.53±1.85).However,the difference between the AVM group with and that without embolization treatment history was statistically significant (24.39±2.10 vs.28.80±1.13,P <0.01).In the group with gamma knife radiotherapy history,OPN expression was found in arteries with early-stage radio-effect.Conclusions OPN may contribute to the vascular instability of brain AVMs.It may play an important role in the pathophysiological process related to embolization treatment.

  5. Surgical Assisting

    Science.gov (United States)

    ... Insert and remove Foley urinary bladder catheter Place pneumatic tourniquet Confirm procedure with surgeon Drape patient within ... Technology and Surgical Assisting (NBSTSA) offers the CertifiedSurgical First Assistant (CSFA) credential, and the National Surgical Assistant ...

  6. [Temporary vascular shunt technique for resource scarce environments].

    Science.gov (United States)

    Ouattara, N; Mlynski, A; Pierret, C

    2011-10-01

    The purpose of this report is to describe a simple and reproducible technique for temporary vascular shunting. This technique is appropriate only for exceptional situations involving scant resource availability. It is not intended to replace conventional vascular shunting techniques.

  7. Surgical management of hydrocephalus secondary to intraventricular hemorrhage in the preterm infant.

    Science.gov (United States)

    Christian, Eisha A; Melamed, Edward F; Peck, Edwin; Krieger, Mark D; McComb, J Gordon

    2016-03-01

    OBJECT Posthemorrhagic hydrocephalus (PHH) in the preterm infant remains a major neurological complication of prematurity. The authors first described insertion of a specially designed low-profile subcutaneous ventricular catheter reservoir for temporary management of hydrocephalus in 1983. This report presents the follow-up experience with the surgical management of PHH in this population and describes outcomes both in infants who were stable for permanent shunt insertion and those initially temporized with a ventricular reservoir (VR) prior to permanent ventriculoperitoneal (VP)/ventriculoatrial (VA) shunt placement. METHODS A retrospective review was undertaken of the medical records of all premature infants surgically treated for posthemorrhagic hydrocephalus (PHH) between 1997 and 2012 at Children's Hospital Los Angeles. RESULTS Over 14 years, 91 preterm infants with PHH were identified. Fifty neonates received temporizing measures via a VR that was serially tapped for varying time periods. For the remaining 41 premature infants, VP/VA shunt placement was the first procedure. Patients with a temporizing measure as their initial procedure had undergone CSF diversion significantly earlier in life than those who had permanent shunting as the initial procedure (29 vs 56 days after birth, p hydrocephalus and shunt infection did not statistically differ between the 2 groups. CONCLUSIONS Patients with initial VR insertion as a temporizing measure received a CSF diversion procedure significantly earlier than those who received a permanent shunt as their initial procedure. Otherwise, the outcomes with regard to shunt revisions, loculated hydrocephalus, and shunt infection were not different for the 2 groups.

  8. Delayed Intracerebral Hemorrhage Secondary to Ventriculoperitoneal Shunt

    Science.gov (United States)

    Ma, Li; Chen, Yi-Li; Yang, Shu-Xu; Wang, Yi-Rong

    2015-01-01

    Abstract The ventriculoperitoneal (VP) shunt is a routine procedure for cerebrospinal fluid (CSF) diversion, and is associated with many complications. A delayed hemorrhage after the VP shunt surgery, however, is quite rare. In this study, we report a case involving late-onset hemorrhage. The 67-year-old male patient with a history of head trauma and brain surgery underwent a VP shunt placement for hydrocephalus. The surgery course was uneventful and no bleeding was revealed in the first computed tomographic (CT) scan after the procedure. However, a massive intraparenchymal and intraventricular hemorrhage occurred 8 h following adjustment of the valve system on the 8th day after surgery. Erosion of the vasculature by catheter cannulation and a sudden reduction of CSF pressure after downregulation of the valve could be one of the possible causes of the intracerebral hemorrhage (ICH). PMID:26632700

  9. Shunt Active Filter in Damping Harmonics Propagation

    Directory of Open Access Journals (Sweden)

    BERBAOUI, B.

    2010-08-01

    Full Text Available This paper deals with a hybrid shunt active power filter applied on 500 kV HVDC, after a description of the causes and effects harmonic pollution which may damage equipments and interrupt electric power customers service; in this paper we present the deferent solutions of this problem among one has to study the two most recent types of filtering: passive and hybrid filter. The hybrid filter consists of active filter connected in shunt with passive filter. The hybrid shunt active filter proposed is based on three levels PWM inverter and characterized by detecting the harmonic current flowing into the passive filter and controlled by notch algorithm. This structure has been applied on a test HVDC power system, is presented as a technical solution makes it possible to eliminate the disadvantages from passive filtering, and also economic price of active filtering part. The simulation results justified the effectiveness of this type of filter face of the classic passive filter.

  10. Flow Field Characterization Inside an Arteriovenous Graft-to-Vein Anastomosis Under Pulsatile Flow Conditions

    Science.gov (United States)

    2007-11-02

    1 FLOW FIELD CHARACTERIZATION INSIDE AN ARTERIOVENOUS GRAFT- TO-VEIN ANASTOMOSIS UNDER PULSATILE FLOW CONDITIONS Nurullah Arslan1, Francis Loth2...the relationship between the distribution of turbulence intensity and the localization of stenoses inside the venous anastomosis of arteriovenous (A...found to be greatest downstream of the anastomosis . KEYWORDS: Arteriovenous graft, dialysis, turbulence, stenosis I. INTRODUCTION

  11. Development of a huge varix following endovascular embolization for cerebellar arteriovenous malformation

    Energy Technology Data Exchange (ETDEWEB)

    Mineura, K.; Sasajima, H.; Itoh, Y.; Kowada, M. [Akita Univ. Hospital (Japan). Neurosurgical Service; Tomura, N. [Akita Univ. Hospital (Japan). Dept. of Radiology; Goto, K. [Iizuka Hospital, Fukuoka (Japan). Dept. of Interventional Neuroradiology

    1998-03-01

    We report on the case of a huge varix that developed after the endovascular embolization of a cerebellar arteriovenous malformation (AVM) with a single drainer. A 21-year-old male presented with trigeminal neuralgia which was caused by the dilated drainer of the AVM. A varix was found at the basal vein of Rosenthal 2 months after an initial stage of embolization with polyvinyl alcohol particles; it diminished after the surgical extirpation of the AVM. The varix formation might have been facilitated by the stenosis in the vein of Galen and by the dynamic changes that followed the embolization. This rare complication should be kept in mind when embolization is performed for AVMs with impaired venous outlets. (orig.).

  12. Spontaneous intracranial hemorrhage in children – ruptured lobar arteriovenous malformations: report of two cases

    Directory of Open Access Journals (Sweden)

    Tascu A.

    2015-03-01

    Full Text Available Brain arteriovenous malformations (AVMs are lesions thought to be primarily congenital in origin, consisting of fistulous connections of abnormal arteries and veins, without normal intervening capillary beds and no cerebral parenchyma between vessels. In the pediatric population, AVMs represent the most common cause of spontaneous intracranial hemorrhage (ICH, with a high recurrent bleeding risk. The aim of this paper is to report 2 cases of ruptured lobar AVMs in children, presenting with spontaneous ICH. Due to the patients’ neurological status, the only imaging examination performed preoperatively was a CT scan, showing intraparenchymal hemorrhage. Thus, there was no MRI/angiographic examination to prove the existence of a brain AVM prior to the surgical interventions. Also, the cerebral angiography performed after the surgery showed, in both patients, no signs of residual vascular malformations. Therefore, the diagnosis of AVM was certified by macroscopic and microscopic pathological findings, with no brain imaging suggestive of a vascular malformation.

  13. [A case of multiple arteriovenous fistulae in a postphlebitic syndrome of longterm evolution].

    Science.gov (United States)

    Delgado Daza, R; Moga Donadeu, L; Mañosa Bonamich, J; Muncunill Gil, J; Vidal Conde, V

    1992-01-01

    Authors report a case of a 77-years-old man who, after an accident of traffic on 1968, presented a left ileo-femoral deep venous thrombosis. Consequently, the patient suffered and important postphlebitic syndrome, with several varicose packs which were treated by surgical procedure in other centre. During several years, patient presented severe trophic diseases. Seventeen years after the beginning of his pathology, and during an angiologic examination, multiple arteriovenous fistulas at the left ileofemoral area have been shown. An skeletalization was impossible because of the severe ulcerations of the leg; so a left iliac arterial ligature and a Dacron Banding in primitive iliac artery, reducing a 50% the diameter, were made. The postoperative result was excellent, with an spectacular reduction of the fistulous communications and a complete remission of the cutaneous ulcerations.

  14. Therapeutic embolization of cavernous sinus dural arteriovenous fistulas via transvenous approach

    Institute of Scientific and Technical Information of China (English)

    侯凯; 罗祺; 陈强; 王宏磊; 罗毅男; 王长坤

    2003-01-01

    Objective To describe the transvenous catheterization technique for the treatment of cavernous sinus dural arteriovenous fistulas (CSdAVFs), including its indications, complications and efficacy.Methods Eight patients with symptomatic CSdAVFs were treated by endovascular embolization with platinum coils, via the inferior petrosal sinus (IPS) in 6 patients, and via the Sylvian vein after surgical exposure in other 2 patients.Results Complete angiographic resolution of the fistula was obtained in six patients immediately after the procedures, and a complete resolution of symptoms and signs was achieved in all patients. The residual fistulas in two patients disappeared completely in the follow-up angiography.Conclusion Transvenous embolization is a useful and safe approach in the management of CSdAVFs.

  15. Spontaneous extrusion of peritoneal catheter of ventriculoperitoneal shunt through the intact abdominal wall: Report of two cases

    Directory of Open Access Journals (Sweden)

    Souvagya Panigrahi

    2012-01-01

    Full Text Available Among the various complications associated with ventriculoperitoneal shunt (VPS surgery, migration of the peritoneal catheter is one of the rarest complications. We report two cases of spontaneous extrusion of the peritoneal portion of the VPS through the intact abdominal wall at an area unrelated to the surgical incision. Both were conscious and had no neurological deficits. There were no signs of infection. The peritoneal end of the shunt was removed through the abdomen. Shunt revision was performed. The patients were discharged 8 days after the revision without any complications. At 6-month follow-up, both of them are doing well. Possible mechanisms of abdominal wall perforation are discussed. Pulling the extruded peritoneal end through abdominal wall decreases the possibility of infection and is probably the best way of management.

  16. Round worm migration along ventriculoperitoneal shunt tract: a rare complication.

    Directory of Open Access Journals (Sweden)

    Agarwal P

    2000-01-01

    Full Text Available Though a ventriculoperitoneal shunt has been associated with myriads of unusual complications, so has been that with roundworms. A case of a three-year-old boy is presented who had an unusual complication of roundworm migration along the shunt tract that presented as shunt tract infection.

  17. [Syringosubarachnoid shunt for noncommunicating syringomyelia associated with spinal lipoma: a case report].

    Science.gov (United States)

    Yamamuro, Shun; Morishita, Takashi; Watanabe, Takao; Maejima, Sadahiro; Katayama, Yoichi

    2012-06-01

    Noncommunicating syringomyelia may complicate repeated untethering procedures in patients with spinal lipomas. Surgical intervention is indicated when syringomyelia is symptomatic. However, the preferred surgical procedure for noncommunicating syringomyelia associated with spinal lipomas has not been established. The authors report a case of noncommunicating syringomyelia associated with a spinal lipoma which was successfully treated with a syringosubarachnoid (S-S) shunt. The patient was a 9-year-old girl with a past history of an excision of a dermal sinus at the age of three months and an untethering of the spinal cord at the age of five. She developed a gait disturbance in the year prior to surgery, and a magnetic resonance imaging (MRI) study demonstrated syringomyelia from the second thoracic vertebra to the fourth lumbar vertebra. S-S shunt surgery successfully addressed the syringomyelia without adverse events, and a follow-up MRI study showed reduction of the size of the lesion. S-S shunt placement was therefore considered to be an effective treatment option for noncommunicating syringomyelia associated with a spinal lipoma.

  18. Early follow-up results of arteriovenous fistulae created for hemodialysis

    Directory of Open Access Journals (Sweden)

    Iyem H

    2011-05-01

    Full Text Available Hikmet IyemÇanakkale 18 Mart, Üniversitesi Tip Fakültesi, TurkeyBackground: The aim of this study was to evaluate the site, early results, and postoperative complications of arteriovenous fistula (AVF creation procedures for hemodialysis in our clinic.Methods: The hospital records of 384 patients who underwent 411 AVF creation procedures for hemodialysis by the same team at our clinic between February 2008 and January 2010 were included for retrospective analysis. All procedures were performed under local anesthesia with lidocaine. Vasospasm was treated by mechanical dilatation with a probe and topical papaverine.Results: Of our 384 patients, 58.5% were male and 41.5% were female. Mean age was 46 (range 12–72 years. Of the 411 AVF procedures performed, 106 (25.8% were created at the anatomical snuffbox, 264 (64.3% were Brescia–Cimino procedures, and 41 (9.9% were antecubital, brachiocephalic, or brachiobasilic procedures. Twenty-three patients (5.98% were subjected to more than one surgical intervention due to early thrombosis or failure of AVF. Early patency was found in 94.0% of the AVF created. Twenty-three patients underwent more than one surgical intervention due to early AVF thrombosis or failure. Early AVF failure occurred more often in females (60.8% than in males (39.2%. Complications were observed in a total of 11.4% patients.Conclusion: Mechanical dilatation of the artery and vein, before starting the anastomosis, as well as the use of vasodilatory agents, could decrease early thrombosis of the fistula, and this method has very high early patency.Keywords: end-stage renal failure, arteriovenous fistula, early patency, complications

  19. Subacute bacterial endocarditis and subsequent shunt nephritis from ventriculoatrial shunting 14 years after shunt implantation

    DEFF Research Database (Denmark)

    Burström, Gustav; Andresen, Morten; Bartek, Jiri Jr.

    2014-01-01

    of inconclusive multidisciplinary investigations, the patient progressed into end-stage renal disease before an echocardiogram revealed a vegetative plaque on the tendinous chords of the tricuspid valve. CSF cultures were grown from the shunt valve, confirming bacterial growth of Propionibacterium acnes suspected...

  20. Is a Swine Model of Arteriovenous Malformation Suitable for Human Extracranial Arteriovenous Malformation? A Preliminary Study

    Energy Technology Data Exchange (ETDEWEB)

    Lv, Ming-ming, E-mail: lvmingming001@163.com [Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Department of Oral and Maxillofacial Surgery, Shanghai Key Laboratory of Stomatology (China); Fan, Xin-dong, E-mail: fanxindong@yahoo.com.cn [Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Department of Radiology (China); Su, Li-xin, E-mail: sulixin1975@126.com [Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Department of Oral and Maxillofacial Surgery, Shanghai Key Laboratory of Stomatology (China)

    2013-10-15

    Objective: A chronic arteriovenous malformation (AVM) model using the swine retia mirabilia (RMB) was developed and compared with the human extracranial AVM (EAVM) both in hemodynamics and pathology, to see if this brain AVM model can be used as an EAVM model. Methods: We created an arteriovenous fistula between the common carotid artery and the external jugular vein in eight animals by using end-to-end anastomosis. All animals were sacrificed 1 month after surgery, and the bilateral retia were obtained at autopsy and performed hematoxylin and eosin staining and immunohistochemistry. Pre- and postsurgical hemodynamic evaluations also were conducted. Then, the blood flow and histological changes of the animal model were compared with human EAVM. Results: The angiography after operation showed that the blood flow, like human EAVM, flowed from the feeding artery, via the nidus, drained to the draining vein. Microscopic examination showed dilated lumina and disrupted internal elastic lamina in both RMB of model and nidus of human EAVM, but the thickness of vessel wall had significant difference. Immunohistochemical reactivity for smooth muscle actin, angiopoietin 1, and angiopoietin 2 were similar in chronic model nidus microvessels and human EAVM, whereas vascular endothelial growth factor was significant difference between human EAVM and RMB of model. Conclusions: The AVM model described here is similar to human EAVM in hemodynamics and immunohistochemical features, but there are still some differences in anatomy and pathogenetic mechanism. Further study is needed to evaluate the applicability and efficacy of this model.

  1. A Patient with Recurrent Arteriovenous Graft Thrombosis.

    Science.gov (United States)

    Allon, Michael

    2015-12-01

    Arteriovenous grafts (AVGs) are prone to frequent thrombosis that is superimposed on underlying hemodynamically significant stenosis, most commonly at the graft-vein anastomosis. There has been great interest in detecting AVG stenosis in a timely fashion and performing preemptive angioplasty, in the belief that this will prevent AVG thrombosis. Three surveillance methods (static dialysis venous pressure, flow monitoring, and duplex ultrasound) can detect AVG stenosis. Whereas observational studies have reported that surveillance with preemptive angioplasty substantially reduces AVG thrombosis, randomized clinical trials have failed to confirm such a benefit. There is a high frequency of early AVG restenosis after angioplasty caused by aggressive neointimal hyperplasia resulting from vascular injury. Stent grafts prevent AVG restenosis better than balloon angioplasty, but they do not prevent AVG thrombosis. Several pharmacologic interventions to prevent AVG failure have been evaluated in randomized clinical trials. Anticoagulation or aspirin plus clopidogrel do not prevent AVG thrombosis, but increase hemorrhagic events. Treatment of hyperhomocysteinemia does not prevent AVG thrombosis. Dipyridamole plus aspirin modestly decreases AVG stenosis or thrombosis. Fish oil substantially decreases the frequency of AVG stenosis and thrombosis. In patients who have exhausted all options for vascular access in the upper extremities, thigh AVGs are a superior option to tunneled internal jugular vein central vein catheters (CVCs). An immediate-use AVG is a reasonable option in patients with recurrent CVC dysfunction or infection. Tunneled femoral CVCs have much worse survival than internal jugular CVCs.

  2. Large spinal intraosseous arteriovenous fistula: case report.

    Science.gov (United States)

    Imajo, Yasuaki; Kanchiku, Tsukasa; Yoshida, Yuichiro; Nishida, Norihiro; Taguchi, Toshihiko

    2015-04-01

    Here the authors report the case of a fresh vertebral body fracture with a large spinal intraosseous arteriovenous fistula (AVF). A 74-year-old woman started to experience low-back pain following a rear-end car collision. Plain radiography showed diffuse idiopathic skeletal hyperostosis (DISH). Sagittal CT sections revealed a transverse fracture of the L-4 vertebral body with a bone defect. Sagittal fat-suppressed T2-weighted MRI revealed a flow void in the fractured vertebra. Spinal angiography revealed an intraosseous AVF with a feeder from the right L-4 segmental artery. A fresh fracture of the L-4 vertebral body with a spinal intraosseous AVF was diagnosed. Observation of a flow void in the vertebral body on fat-suppressed T2-weighted MRI was important for the diagnosis of the spinal intraosseous AVF. Because conservative treatment was ineffective, surgery was undertaken. The day before surgery, embolization through the right L-4 segmental artery was performed using 2 coils to achieve AVF closure. Posterolateral fusion with instrumentation at the T12-S2 vertebral levels was performed without L-4 vertebroplasty. The spinal intraosseous AVF had disappeared after 4 months. At 24 months after surgery, the bone defect was completely replaced by bone and the patient experienced no limitations in daily activities. Given their experience with the present case, the authors believe that performing vertebroplasty or anterior reconstruction may not be necessary in treating spinal intraosseous AVF.

  3. Diagnosis and evaluation of intracranial arteriovenous malformations

    Science.gov (United States)

    Conger, Andrew; Kulwin, Charles; Lawton, Michael T.; Cohen-Gadol, Aaron A.

    2015-01-01

    Background: Ideal management of intracranial arteriovenous malformations (AVMs) remains poorly defined. Decisions regarding management of AVMs are based on the expected natural history of the lesion and risk prediction for peritreatment morbidity. Microsurgical resection, stereotactic radiosurgery, and endovascular embolization alone or in combination are all viable treatment options, each with different risks. The authors attempt to clarify the existing literature's understanding of the natural history of intracranial AVMs, and risk-assessment grading scales for each of the three treatment modalities. Methods: The authors conducted a literature review of the existing AVM natural history studies and studies that clarify the utility of existing grading scales available for the assessment of peritreatment risk for all three treatment modalities. Results: The authors systematically outline the diagnosis and evaluation of patients with intracranial AVMs and clarify estimation of the expected natural history and predicted risk of treatment for intracranial AVMs. Conclusion: AVMs are a heterogenous pathology with three different options for treatment. Accurate assessment of risk of observation and risk of treatment is essential for achieving the best outcome for each patient. PMID:25984390

  4. Retrograde migration and subcutaneous coiling of the peritoneal catheter of a ventriculoperitoneal shunt in a cat

    Directory of Open Access Journals (Sweden)

    Sinead E Bennett

    2016-04-01

    Full Text Available Case summary Ventriculoperitoneal shunt placement is the most commonly utilised surgical treatment for hydrocephalus in human and veterinary patients. Migration of the peritoneal catheter is an uncommon but well-documented complication in people, usually occurring within the first 3 months postoperatively, although only a single feline case report exists. A ventriculoperitoneal shunt was placed in a domestic shorthair cat, aged 4 years and 10 months, following a diagnosis, with MRI, of unilateral, non-communicating hydrocephalus. Diarrhoea, increased vocalisation and pruritus were reported within the first 3 months postoperatively. A shunt-associated seroma developed, which was aspirated under ultrasound guidance. Within 3 days, the entire peritoneal catheter was subcutaneously coiled at the level of the seroma. The peritoneal catheter was replaced within the abdomen via a new subcutaneous tunnel. No further complications had occurred 24 months following revision surgery. Relevance and novel information This is the second report describing peritoneal catheter migration in a cat. Repetitive head and neck movements during self-grooming, raised intra-abdominal pressure secondary to vocalisation and tenesmus, and negative pressure exerted during seroma aspiration may have contributed to ventriculoperitoneal shunt migration. Excessive loose skin and increased activity may further increase the risk of migration in cats. Diagnostic imaging should be offered prior to and following aspiration of shunt-associated swellings, and minimal negative pressure should be exerted. Attempts to reduce the frequency of postoperative self-grooming, prevention and prompt treatment of conditions predisposing to raised intra-abdominal pressure and moderate exercise restriction, particularly within the first 3 months, may help reduce the risk of peritoneal catheter migration.

  5. Laparoscopic management of complicated ventriculoperitoneal shunts

    Directory of Open Access Journals (Sweden)

    Jain S

    2003-04-01

    Full Text Available Intra-abdominal migration of the catheter and formation of a cerebrospinal fluid pseudocyst are both rare complications of a ventriculoperitoneal shunt. Traditionally, each condition is treated by a formal laparotomy. Laparoscopic management of the complications in two patients is described.

  6. ARTIFICIAL SHUNTING OF CEREBROSPINAL-FLUID

    NARCIS (Netherlands)

    HOEKSTRA, A

    1994-01-01

    A compact three-stage shunt valve system (Orbis SigmaTM Valve) which operates as a flow regulator within certain differential pressure values has been clinically evaluated in the treatment of hydrocephalus. Clinical trials were performed in 134 cases, covering 128 patients aged from 1 day to 79 year

  7. Is Subdural Peritoneal Shunt Placement an Effective Tool for the Management of Recurrent/Chronic Subdural Hematoma?

    Science.gov (United States)

    Alvarez-Pinzon, Andres M; Valerio, Jose E; Delgado, Victor; Escalante, Jennifer A; Lopez, Nithia; Wolf, Aizik L

    2016-01-01

    Objective  To describe a surgical technique and to report using a retrospective study the efficacy of peritoneal shunts for the treatment of recurrent/chronic subdural hematoma (CSDH). We describe the considerations, complications, and outcomes related to this technique. Methods  In a retrospective cohort study, 125 charts with a diagnosis of subacute/chronic subdural hematoma were assigned for evaluation. Of the charts reviewed, 18 charts were found from subjects with a diagnosis of recurrent sub-acute or chronic subdural hematoma. All patients had undergone initial surgical treatment of their condition followed by peritoneal shunt placement to help alleviate intracranial pressure. Factors including the age, size of subdural hematoma, number of previous events, BMI, complications, survival, and clinical course were analyzed. Results  After subdural peritoneal shunt placement all patients had full neurological recovery with no complaints of headaches, lethargy, weakness, confusion or seizures. None of the cases had new subdural hematoma episodes after placement for a minimum of a two-year period (mean 26.1 months) (range 24.3-48.6 months). No postoperative complications were reported. The rates of postoperative hemorrhage, infection, distal catheter revision, and perioperative seizures was found to be zero percent. Shunt drainage was successful in all cases, draining 85% of the blood in the first 48 hours. There was no significant relationship between complications and the use of anticoagulants four weeks after surgery. Conclusions Peritoneal shunts, though rarely used, are a viable option in the treatment of sub-acute/chronic subdural hematomas. When pursuing this treatment, this technique is recommended to mitigate the risks of repeat surgical intervention and lessen perioperative time in high-risk patients. PMID:27335718

  8. Volume Flow in Arteriovenous Fistulas Using Vector Velocity Ultrasound

    DEFF Research Database (Denmark)

    Hansen, Peter Møller; Olesen, Jacob Bjerring; Pihl, Michael Johannes;

    2014-01-01

    Volume flow in arteriovenous fistulas for hemodialysis was measured using the angle-independent ultrasound technique Vector Flow Imaging and compared with flow measurements using the ultrasound dilution technique during dialysis. Using an UltraView 800 ultrasound scanner (BK Medical, Herlev......, Denmark) with a linear transducer, 20 arteriovenous fistulas were scanned directly on the most superficial part of the fistula just before dialysis. Vector Flow Imaging volume flow was estimated with two different approaches, using the maximum and the average flow velocities detected in the fistula. Flow...

  9. Passively Shunted Piezoelectric Damping of Centrifugally-Loaded Plates

    Science.gov (United States)

    Duffy, Kirsten P.; Provenza, Andrew J.; Trudell, Jeffrey J.; Min, James B.

    2009-01-01

    Researchers at NASA Glenn Research Center have been investigating shunted piezoelectric circuits as potential damping treatments for turbomachinery rotor blades. This effort seeks to determine the effects of centrifugal loading on passively-shunted piezoelectric - damped plates. Passive shunt circuit parameters are optimized for the plate's third bending mode. Tests are performed both non-spinning and in the Dynamic Spin Facility to verify the analysis, and to determine the effectiveness of the damping under centrifugal loading. Results show that a resistive shunt circuit will reduce resonant vibration for this configuration. However, a tuned shunt circuit will be required to achieve the desired damping level. The analysis and testing address several issues with passive shunt circuit implementation in a rotating system, including piezoelectric material integrity under centrifugal loading, shunt circuit implementation, and tip mode damping.

  10. A Meta-analysis of Randomized Trials Comparing Surgery versus Endovascular Therapy for Thrombosed Arteriovenous Fistulas and Grafts in Hemodialysis

    Energy Technology Data Exchange (ETDEWEB)

    Kuhan, G., E-mail: gkuhan@nhs.net; Antoniou, G. A. [Central Manchester University Hospital Foundation Trust, Regional Vascular and Endovascular Unit (United Kingdom); Nikam, M.; Mitra, S. [Central Manchester University Hospital Foundation Trust, Department of Renal Medicine (United Kingdom); Farquharson, F. [Central Manchester University Hospital Foundation Trust, Department of Radiology (United Kingdom); Brittenden, J. [University of Aberdeen (United Kingdom); Chalmers, N. [Central Manchester University Hospital Foundation Trust, Department of Radiology (United Kingdom)

    2013-06-15

    Purpose. To carry out a systematic review of randomized trials comparing surgery vs. endovascular therapy for occluded fistulas and grafts. Methods. All randomized trials which compared surgery and endovascular therapy for occluded fistulas and grafts were retrieved from 1990 onwards. The following search terms were used: 'haemodialysis,' 'thrombosis,' 'arteriovenous fistula,' 'arteriovenous shunt,' 'end stage renal failure' on Medline and PubMed. The results of the pooled data were analysed by a fixed-effect model. Results. There were no randomized trials comparing surgery vs. endovascular therapy for native fistulas and vein grafts. Six randomized studies reporting on 573 occluded grafts were identified. Technical success, need for access line and primary patency at 30 days were similar between the two groups (odds ratio [OR] 1.40, 95 % confidence interval [CI] 0.91-2.14; OR 0.77, 95 % CI 0.44-1.34; and OR 1.15, 95 % CI 0.79-1.68, respectively). There was no significant difference in morbidity at 30 days between groups (OR 1.12, 95 % CI 0.67-1.86). There were no statistical difference between the two groups for 1 year primary patency (OR 2.08, 95 % CI 0.97-4.45). Primary assisted patency at 1 year was better with surgery (OR 3.03, 95 % CI 1.12-8.18) in a single study. Conclusion. Comparable results to surgery have been achieved with endovascular techniques for occluded prosthetic grafts for dialysis access. Long-term data comparing the two groups were lacking. Further trials designed to encompass variation in methods are warranted in order to obtain the best available evidence particularly for native fistulas.

  11. Percutaneous treatment of thrombosed native arteriovenous dialysis fistula insufficiency: efficacy of mechanical thrombectomy with using the stone basket

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Hwan; Ko, Sung Min; Kim, Mi Jung; Kwon, Jung Hyeok; Sohn, Cheol Ho; Choi, Jin Soo; Park, Kyung Sik [Dongsan Medical Center, Keimyung University College of Medicine, Daegu (Korea, Republic of); Kim, Yong Joo [Andong General Hospital, Andon (Korea, Republic of)

    2006-06-15

    We wanted to evaluate the procedural success after percutaneous treatment of thrombosed native arteriovenous dialysis fistula insufficiency and the efficacy of performing mechanical thrombectomy with using the stone basket. From March 2004 to June 2005, 36 thrombosed native hemodialysis access shunts in the upper limbs (brachiocephalic fistulas: 16 and radiocephalic fistulas: 20) were percutaneously treated in 30 patients. Declotting procedures were performed with using urokinase (100,00-200,000 unit) and manual catheter-directed thrombo-aspiration in all the patients. Angioplasty (6 mm in diameter and 4 cm in length) was performed at the identified area of the stenosis and /or with maceration of the thrombus. In 14 cases with massive thrombosis that was refractory to the above mentioned declotting procedures, mechanical thrombectomy with using a Wittich nitinol stone basket (Cook, Bloomington, IN) was performed. Data regarding the procedural success rate and the patency rate were analyzed by means of Fischer's exact test, and the Kaplan-Meier method with the Log-rank test was used for statistical inter-group comparisons between the brachiocephalic and radiocephalic fistulas. Successful declotting and restoration of thrill were achieved in 30 of 36 procedures (83%). Reestablishment of normal dialysis for at least one session was achieved in 29 of 36 procedures (81%). The procedural success rate for the brachiocephalic fistulas was 94% compared with 70% for the radiocephalic fistulas, but the difference was not statistically significant ({rho} = 0.104). In the cases with performing mechanical thrombectomy and using the stone basket, procedural success was achieved in 93% (13/14). The expected patency rates at 3, 6 and 12 months were 78%, 61% and 51%, respectively. The patency rates after declotting procedures were not significantly different between the brachiocephalic and radiocephlaic fistulas ({rho} = 0.871). Percutaneous treatment of thrombosed native

  12. A rare association of cerebral dural arteriovenous fistula with venous aneurysm and contralateral flow-related middle cerebral artery aneurysm.

    Science.gov (United States)

    Onu, David O; Hunn, Andrew W; Harle, Robin A

    2013-09-19

    The association of cerebral dural arteriovenous fistula (DAVF) and ipsilateral flow related aneurysm has infrequently been reported. We describe a male patient who presented with an acute haemorrhagic stroke and was found to have a large right fronto-parietal intra-parenchymal haemorrhage from the ruptured Borden type II DAVF in addition to a large venous aneurysm and a flow related intraosseous aneurysm of the contralateral middle meningeal artery (MMA) all clearly delineated by CT and DSA. He underwent emergency stereotactic evacuation of the intraparenchymal haemorrhage and successful surgical treatment of all the vascular lesions at the same time with residual neurological deficit. To our knowledge, this is the first such reported case. We discuss the challenging surgical treatment, emphasising the role of CT/DSA in management, and provide a literature review.

  13. Pathological Predictors of Shunt Stenosis and Hepatic Encephalopathy after Transjugular Intrahepatic Portosystemic Shunt

    Directory of Open Access Journals (Sweden)

    Fuliang He

    2016-01-01

    Full Text Available Background. Transjugular intrahepatic portosystemic shunt (TIPS is an artificial channel from the portal vein to the hepatic vein or vena cava for controlling portal vein hypertension. The major drawbacks of TIPS are shunt stenosis and hepatic encephalopathy (HE; previous studies showed that post-TIPS shunt stenosis and HE might be correlated with the pathological features of the liver tissues. Therefore, we analyzed the pathological predictors for clinical outcome, to determine the risk factors for shunt stenosis and HE after TIPS. Methods. We recruited 361 patients who suffered from portal hypertension symptoms and were treated with TIPS from January 2009 to December 2012. Results. Multivariate logistic regression analysis showed that the risk of shunt stenosis was increased with more severe inflammation in the liver tissue (OR, 2.864; 95% CI: 1.466–5.592; P=0.002, HE comorbidity (OR, 6.266; 95% CI, 3.141–12.501; P<0.001, or higher MELD score (95% CI, 1.298–1.731; P<0.001. Higher risk of HE was associated with shunt stenosis comorbidity (OR, 6.266; 95% CI, 3.141–12.501; P<0.001, higher stage of the liver fibrosis (OR, 2.431; 95% CI, 1.355–4.359; P=0.003, and higher MELD score (95% CI, 1.711–2.406; P<0.001. Conclusion. The pathological features can predict individual susceptibility to shunt stenosis and HE.

  14. Effects of danshensu on platelet aggregation and thrombosis: in vivo arteriovenous shunt and venous thrombosis models in rats.

    Directory of Open Access Journals (Sweden)

    Chen Yu

    Full Text Available Danshensu, a type of dihydroxyphenyl lactic acid, is one of the most abundant active phenolic acids in the dried root of Salvia miltiorrhizae (Lamiaceae--widely used traditional Chinese medicine. The effects of danshensu on platelet aggregation and thrombus formation in rats were examined using various methods. It was found that danshensu significantly reduced thrombus weight in 2 experimental thrombosis models; dose-dependent inhibition of adenosine diphosphate (ADP and arachidonic acid (AA-induced platelet aggregation occurred in normal and blood stasis-induced rats; Danshensu also significantly mitigated blood viscosity, plasma viscosity and hematocrit levels. Moreover, danshensu significantly inhibited venous thrombosis-induced expression of cyclooxygenases-2 (COX-2 rather than cyclooxygenases-1(COX-1 in the venous walls, down regulated thromboxane B2 (TXB2 and up regulated 6-keto prostaglandin F1α (6-keto-PGF1α, normalizing the TXB2/6-keto-PGF1α ratio. In addition, danshensu did not induce gastric lesions and even had protective effects on aspirin-induced ulcer formation at doses as high as 60 mg/kg. These findings suggest that the antithrombotic and antiplatelet aggregation effects of danshensu are attributed to its highly selective inhibition of COX-2 and ability to normalize the thromboxane A2(TXA2/prostacyclin(PGI2 balance. These findings suggest that danshensu have great prospects in antithrombotic and antiplatelet therapy.

  15. A mathematical model of continuous arterio-venous hemodiafiltration (CAVHD)

    NARCIS (Netherlands)

    E. Akcahuseyin (Emin); H.H. Vincent (Jeroen); F.J. van Ittersum (Frans); W.A. van Duyl (Wim); M.A.D.H. Schalekamp (Maarten)

    1990-01-01

    textabstractAbstract Continuous arterio-venous hemodiafiltration (CAVHD) differs from conventional hemofiltration and dialysis by the interaction of convection and diffusion, the use of very low dialysate flow rates and by the deterioration of membrane conditions during the treatment. In order to st

  16. Occlusion of pulmonary arteriovenous malformations by use of vascular plug

    DEFF Research Database (Denmark)

    Andersen, P E; Kjeldsen, A D

    2007-01-01

    Pulmonary arteriovenous malformations are commonly treated by embolization with coils or balloons to prevent cerebral complications and to raise the oxygenation of the blood. The Amplatzer vascular plug is a new occlusive device made of a self-expanding cylindrical nitinol mesh. It is fast and safe...

  17. Radial Artery Approach to Salvage Nonmaturing Radiocephalic Arteriovenous Fistulas

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, Mu-Yang; Lin, Lin; Tsai, Kuei-Chin; Wu, Chih-Cheng, E-mail: chihchengwumd@gmail.com [National Taiwan University Hospital, Department of Cardiology (China)

    2013-08-01

    PurposeTo evaluate the usefulness of an approach through the radial artery distal to the arteriovenous anastomosis for salvaging nonmaturing radiocephalic arteriovenous fistulas.MethodsProcedures that fulfilled the following criteria were retrospectively reviewed: (1) autogenous radiocephalic fistulas, (2) fistulas less than 3 months old, (3) distal radial artery approach for salvage. From 2005 to 2011, a total of 51 patients fulfilling the above criteria were enrolled. Outcome variables were obtained from angiographic, clinical and hemodialysis records, including the success, complication, and primary and secondary patency rates.ResultsThe overall anatomical and clinical success rates for the distal radial artery approach were 96 and 94 %, respectively. The average procedure time was 36 {+-} 19 min. Six patients (12 %) experienced minor complications as a result of extravasations. No arterial complication or puncture site complication was noted. The postinterventional 6-month primary patency rate was 51 %, and the 6-month secondary patency rate was 90 %. When the patients were divided into a stenosed group (20 patients) and an occluded group (31 patients), there were no differences in the success rate, complication rate, or primary and secondary patency rates.ConclusionAn approach through the radial artery distal to the arteriovenous anastomosis is an effective and safe alternative for the salvage of nonmaturing radiocephalic arteriovenous fistulas, even for occluded fistulas.

  18. Umbilical arteriovenous malformation in a healthy neonate with umbilical hernia.

    Science.gov (United States)

    Marcelo Boglione, Mariano; D Alessandro, Pablo; Reusmann, Aixa; Rubio, Martín; Lipsich, José; Goldsmith, Gustavo

    2013-01-01

    We describe the case of a neonate with an umbilical hernia and persistent wet umbilicus. Examination revealed a pulsatile umbilical cord with palpable thrill. Doppler ultrasound suspected umbilical arteriovenous malformation and contrast-enhanced computed tomography was performed leading to a definitive diagnosis. Surgery was successfully performed on day 27.

  19. Umbilical Arteriovenous Malformation in a Healthy Neonate with Umbilical Hernia

    OpenAIRE

    2013-01-01

    We describe the case of a neonate with an umbilical hernia and persistent wet umbilicus. Examination revealed a pulsatile umbilical cord with palpable thrill. Doppler ultrasound suspected umbilical arteriovenous malformation and contrast-enhanced computed tomography was performed leading to a definitive diagnosis. Surgery was successfully performed on day 27.

  20. Effects of arteriovenous fistulas on cardiac oxygen supply and demand

    NARCIS (Netherlands)

    Bos, W.J.W.; Zietse, R.; Wesseling, K.H.; Westerhof, N.

    1999-01-01

    Background. Arteriovenous (AV) fistulas used for hemodialysis access may affect cardiac load by increasing the preload while decreasing the afterload. In dogs, AV fistulas have also been shown to affect coronary perfusion negatively. We investigated the net effect of AV fistulas on cardiac oxygen su

  1. Venous aneurysm complicating arteriovenous fistula access and matrix metalloproteinases

    Directory of Open Access Journals (Sweden)

    Serra Raffaele

    2015-01-01

    Full Text Available Introduction: An arteriovenous fistula (AVF for placed for hemodialysis may be burdened by one particular complication-the formation of a venous aneurysm. It has been shown that matrix metalloproteinases (MMPs and neutrophil gelatinase-associated lipocalin (NGAL could represent markers of disease in both venous and arterial vessels.

  2. [Spondylodiscitis after embolization of an extramedullary intraspinal arteriovenous fistula].

    Science.gov (United States)

    Baudrillard, J C; Toubas, O; Lerais, J M; Auquier, F; Gatfosse, M; Bernard, M H

    1985-04-01

    The authors report a case of spondylitis Th11-Th12 occurred 1 month after embolization of an intraspinal extramedullary arteriovenous fistulae; this fistulae was fed by 11th left intercostal artery. The infecting organism isolated from the affected intervertebral disc was streptococcus sanguis a common agent of dental abscess.

  3. Traumatic basilar pseudoaneurysm with a basilar-cavernous arteriovenous fistula

    Energy Technology Data Exchange (ETDEWEB)

    Connor, S.E.J.; Deasy, N.P.; Jeffree, M.A. [Dept. of Neuroradiology, King' s Coll. Hospital, London (United Kingdom); Martin, A.J.; Strong, A.J. [Dept. of Neurosurgery, King' s Coll. Hospital, London (United Kingdom)

    2001-03-01

    A traumatic pseudoaneurysm of the basilar artery with a basilar-cavernous sinus arteriovenous fistula was diagnosed in a 12-year-old girl using CT, MRI and angiography. It was successfully treated by coil embolisation. We speculate on the mode of formation of this rare traumatic lesion. (orig.)

  4. Who Needs a Revision? 20 Years of Cambridge Shunt Lab.

    Science.gov (United States)

    Czosnyka, Zofia; Czosnyka, Marek; Pickard, John D; Chari, Aswin

    2016-01-01

    Shunt testing independent of manufacturers provides knowledge that can significantly improve the management of patients with hydrocephalus. The Cambridge Shunt Evaluation Laboratory was created 20 years ago. Thanks to financial support from the Department of Health (1993-1998), all shunts in use in the UK were systematically evaluated, with "blue reports" being published. Later new devices were tested as they appeared in public domain.Twenty-six models have been evaluated. The majority of the valves had a non-physiologically low hydrodynamic resistance that may result in over-drainage, both related to posture and during nocturnal cerebral vasogenic waves. A long distal catheter increases the resistance of these valves by 100-200 %. Drainage through valves without a siphon-preventing mechanism is very sensitive to body posture. Shunts with siphon-preventing accessories offer a reasonable resistance to negative outlet pressure. Bench parameters were used to test shunt performance in vivo using infusion tests. A criterion for correctly performing a shunt procedure was established. Pressure measured in the shunt prechamber during the plateau phase of infusion should not remain more than 5 mmHg above the le shunt's operating pressure plus hydrodynamic resistance of the valve multiplied by the infusion rate. "Critical levels" for every shunt and every performance level have been used in the shunt testing wizard of ICM+ software.

  5. Factors influencing shunt malfunction in patients with tuberculous meningitis

    Directory of Open Access Journals (Sweden)

    Sudheer Ambekar

    2013-01-01

    Full Text Available Background: Hydrocephalus secondary to tuberculous meningitis (TBM is a challenging condition to treat. Though ventriculo-peritoneal (VP shunt is an accepted modality of treatment for hydrocephalus in TBM, there is a high rate of complications associated with the same. Objective: The study was planned to evaluate various factors associated with shunt malfunction in patients undergoing VP shunt surgery for hydrocephalus due to TBM. Materials and Methods: A retrospective review of all the patients undergoing VP shunt and shunt revision for TBM between 2004 and 2008 was performed. 449 VP shunt surgeries were performed in 432 patients for hydrocephalus due to TBM. Among these 70 shunt revisions were performed in 53 patients. Results: Shunt malfunction rate in our series was 16.2%. High cerebrospinal fluid (CSF protein concentration (>200 mg/dL was associated with 5 times increased incidence of shunt malfunction. Patients with hyponatremia (Na + <130 mEq/dL prior to surgery had a 3 times increased incidence of shunt malfunction (P < 0.05. Other factors such as duration of symptoms, presence of neurological deficits, Evan′s index, third ventricular diameter, thickness of exudates, presence of infarcts, anemia, CSF cellularity and CSF glucose concentration were not associated with increased incidence of shunt malfunction. Analysis showed that shunt viability was longest in patients with normal serum sodium levels and CSF protein concentration less than 200 mg/dL and shortest in patients with low serum sodium and CSF protein concentration more than 200 mg/dL. Conclusions: Patients with pre-operative hyponatremia and high CSF protein concentration have a higher incidence of shunt malfunction and need to be followed-up closely.

  6. Nitrogen heat pipe for cryocooler thermal shunt

    Energy Technology Data Exchange (ETDEWEB)

    Prenger, F.C.; Hill, D.D.; Daney, D.E.; Daugherty, M.A. [Los Alamos National Lab., NM (United States); Green, G.F.; Roth, E.W. [Naval Surface Warfare Center, Annapolis, MD (United States)

    1995-09-01

    A nitrogen heat pipe was designed, built and tested for the purpose of providing a thermal shunt between the two stages of a Gifford-McMahan (GM) cryocooler during cooldown. The nitrogen heat pipe has an operating temperature range between 63 and 123 K. While the heat pipe is in the temperature range during the system cooldown, it acts as a thermal shunt between the first and second stage of the cryocooler. The heat pipe increases the heat transfer to the first stage of the cryocooler, thereby reducing the cooldown time of the system. When the heat pipe temperature drops below the triple point, the nitrogen working fluid freezes, effectively stopping the heat pipe operation. A small heat leak between cryocooler stages remains because of axial conduction along the heat pipe wall. As long as the heat pipe remains below 63 K, the heat pipe remains inactive. Heat pipe performance limits were measured and the optimum fluid charge was determined.

  7. Dc SQUIDs with asymmetric shunt resistors

    Energy Technology Data Exchange (ETDEWEB)

    Rudolph, Matthias; Nagel, Joachim; Kemmler, Matthias; Koelle, Dieter; Kleiner, Reinhold [Physikalisches Institut - Experimentalphysik II and Center for Collective Quantum Phenomena in LISAplus, Universitaet Tuebingen (Germany); Meckbach, Johannes Maximilian; Ilin, Konstantin; Siegel, Michael [Institut fuer Mikro- und Nanoelektronische Systeme, Karlsruhe Institute of Technology, Karlsruhe (Germany)

    2013-07-01

    We have investigated asymmetrically shunted Nb/Al-AlO{sub x}/Nb dc SQUIDs. Simulations based on the coupled Langevin equations predict that the optimum energy resolution ε, and thus also the noise performance of such an asymmetric SQUID, can be 3-4 times better than that of its symmetric counterpart. While keeping the total resistance R identical to a comparable symmetric SQUID with R{sup -1} = R{sub 1}{sup -1} + R{sub 2}{sup -1}, we shunted only one of the two Josephson junctions with R = R{sub 1,2}/2. Both types of SQUIDs were characterized with respect to their transport and noise properties at temperature T = 4.2 K, and we compared the experimental results with numerical simulations. Experiments yielded ε ∼ 32 ℎ for an asymmetric SQUID with an inductance L = 22 pH, whereas a comparable symmetric device achieved ε = 110 ℎ.

  8. A genome-wide investigation of copy number variation in patients with sporadic brain arteriovenous malformation.

    Directory of Open Access Journals (Sweden)

    Nasrine Bendjilali

    Full Text Available BACKGROUND: Brain arteriovenous malformations (BAVM are clusters of abnormal blood vessels, with shunting of blood from the arterial to venous circulation and a high risk of rupture and intracranial hemorrhage. Most BAVMs are sporadic, but also occur in patients with Hereditary Hemorrhagic Telangiectasia, a Mendelian disorder caused by mutations in genes in the transforming growth factor beta (TGFβ signaling pathway. METHODS: To investigate whether copy number variations (CNVs contribute to risk of sporadic BAVM, we performed a genome-wide association study in 371 sporadic BAVM cases and 563 healthy controls, all Caucasian. Cases and controls were genotyped using the Affymetrix 6.0 array. CNVs were called using the PennCNV and Birdsuite algorithms and analyzed via segment-based and gene-based approaches. Common and rare CNVs were evaluated for association with BAVM. RESULTS: A CNV region on 1p36.13, containing the neuroblastoma breakpoint family, member 1 gene (NBPF1, was significantly enriched with duplications in BAVM cases compared to controls (P = 2.2×10(-9; NBPF1 was also significantly associated with BAVM in gene-based analysis using both PennCNV and Birdsuite. We experimentally validated the 1p36.13 duplication; however, the association did not replicate in an independent cohort of 184 sporadic BAVM cases and 182 controls (OR = 0.81, P = 0.8. Rare CNV analysis did not identify genes significantly associated with BAVM. CONCLUSION: We did not identify common CNVs associated with sporadic BAVM that replicated in an independent cohort. Replication in larger cohorts is required to elucidate the possible role of common or rare CNVs in BAVM pathogenesis.

  9. Embolization of brain arteriovenous malformations with ethylene vinyl alcohol copolymer:technical aspects

    Institute of Scientific and Technical Information of China (English)

    GAO Kun; YANG Xin-jian; MU Shi-qing; LI You-xiang; ZHANG You-ping; L(U) Ming; WU Zhong-xue

    2009-01-01

    Background Endovascular therapy plays an important role in the treatment of brain arteriovenous malformations (BAVMs).Ethylene vinyl alcohol copolymer (Onyx) is a novel liquid embolic material.This study aimed to summarize our experience of using Onyx for embolization of BAVMs with the focus on embolization technique.Methods From September 2003 to November 2007,115 patients (43 women and 72 men,with a mean age of 29 years)with BAVMs were endovascularly treated with Onyx in our department.The following features of all AVMs were evaluated prior to treatment:type of nidus and shunt,draining veins,and feeding arteries.A total of 196 endovascular procedures were performed.Results The course of endovascular treatment was completed in 88 patients.Additional sessions were planned in 27 patients.Of the 88 patients,total occlusion was obtained in 23 patients (26.1%),near-total (>80% of the original volume) occlusion was obtained in 35 patients (39.8%) and partial occlusion (<80% of the original volume) was obtained in 30 patients (34.1%) using embolization as the sole therapeutic technique.Mean volume reduction was 72% (range 30%-100%) in 115 patients.Thirty four patients (38.6%,34/88) underwent radiosurgical treatment.Additional embolization sessions were planned in 27 patients.Complications occurred in 19 patients (16.5%,19/115),leading to death in one patient (mortality 0.9%) and permanent disabling in 3 patients (morbidity 2.6%).Conclusions Onyx was shown to be feasible and safe for embolization of BAVMs.Proper use of the Onyx injection technique largely improved the endovascular treatment of BAVMs.Large AVMs can be adequately reduced in size through the use of additional treatment.

  10. Portacaval Shunt for Portal Hypertensive Gastropathy

    Directory of Open Access Journals (Sweden)

    John Craig Collins

    1997-01-01

    Full Text Available Portal hypertensive gastropathy is a vascular disorder of the gastric mucosa distinguished by ectasia of the mucosal capillaries and submucosal veins without inflammation. During 1988 to 1993, 12 patients with biopsyproven cirrhosis (10 alcoholic, 2 posthepatitic were evaluated and treated prospectively by portacaval shunt for active bleeding from severe portal hypertensive gastropathy. Eleven patients had been hospitalized for bleeding three to nine times previously, and one was bleeding uncontrollably for the first time. Requirement for blood transfusions ranged from 11 to 39 units cumulatively, of which 8 to 30 units were required specifically to replace blood lost from portal hypertensive gastropathy. Admission findings were ascites in 9 patients, jaundice in 8, severe muscle wasting in 10, hyperdynamic state in 9. Child's risk class was C in 7, B in 4, A in 1. Ten of the 12 patients had previously received repetitive endoscopic sclerotherapy for esophageal varices, which has been reported to precipitate portal hypertensive gastropathy. Eight patients had failed propranolol therapy for bleeding. Portacaval shunt was performed emergently in 11 patients and electively in 1, and permanently stopped bleeding in all by reducing the mean portal vein-inferior vena cava pressure gradient from 251 to 16 mm saline. There were no operative deaths, and two unrelated late deaths after 13 and 24 months. During 1 to 6.75 years of followup, all shunts remained patent by ultrasonography, the gastric mucosa reverted to normal On serial endoscopy, and there was no gastrointestinal bleeding. Recurrent portal-systemic encephalopathy developed in only 8% of patients. Quality of life was generally good. It is concluded that portacaval shunt provides definitive treatment of bleeding portal hypertensive gastropathy by eliminating the underlying cause, and makes possible prolonged survival with an acceptable quality of life.

  11. The transjugular intrahepatic portosystemic shunt (TIPS)

    Energy Technology Data Exchange (ETDEWEB)

    Owen, A.R. [Department of Radiology, Austin Health, Heidelberg, Melbourne (Australia)], E-mail: andrewowen@doctors.org.uk; Stanley, A.J. [Department of Gastroenterology, Glasgow Royal Infirmary, Glasgow (United Kingdom); Vijayananthan, A. [Department of Biomedical Imaging, University of Malaya, Kuala Lumpur (Malaysia); Moss, J.G. [Department of Radiology, Gartnavel General Hospital, Glasgow (United Kingdom)

    2009-07-15

    The creation of an intrahepatic portosystemic shunt via a transjugular approach (TIPS) is an interventional radiological procedure used to treat the complications of portal hypertension. TIPS insertion is principally indicated to prevent or arrest variceal bleeding when medical or endoscopic treatments fail, and in the management refractory ascites. This review discusses the development and execution of the technique, with focus on its clinical efficacy. Patient selection, imaging surveillance, revision techniques, and complications are also discussed.

  12. Arteriovenous Loop-Independent Free Flap Reconstruction of Sternal Defects after Cardiac Surgery.

    Science.gov (United States)

    Dornseifer, Ulf; Kleeberger, Charlotte; Ehrl, Denis; Herter, Frank; Ninkovic, Milomir; Iesalnieks, Igors

    2016-09-01

    Background Sternal defects following deep wound infections are predominantly reconstructed using local and regional flaps. The lack of appropriate recipient vessels after cardiac surgery may explain the minor role of free flaps. To date, arteriovenous loops have been the leading solution to enable microsurgical closure of these defects. However, the related surgical effort and the risk of flap failure are increased. We reviewed our experiences with the right gastroepiploic vessels as alternative recipient vessels for free flap reconstructions. Methods Between September 2010 and July 2015, 12 patients suffering deep wound infection after cardiac surgery underwent sternal reconstruction with free flaps anastomosed to the right gastroepiploic vessels. Gracilis flaps (n = 8) and anterolateral thigh perforator flaps (n = 4) were used for sternal reconstruction. Recipient vessels were harvested by laparoscopic dissection in five patients. Half of the free flaps were variably combined with omental flow-through flaps. Results Healing of all flaps was uneventful with no partial or total flap loss. Simultaneous interdisciplinary harvesting of recipient vessels by laparoscopy significantly shortened mean operative time from 313 to 216 minutes (p = 0.018). One incisional hernia was observed in the laparotomy group. Revision of a gracilis donor site was necessary in another patient due to postoperative bleeding. No recurrent sternal infection occurred during a mean follow-up of 20 months (range, 3-59 months). Conclusions The concept of gastroepiploic recipient vessels allows reliable free flap reconstructions of sternal defects in such high-risk patients without the need for arteriovenous loops.

  13. The role of SDF-1/CXCR4 in the vasculogenesis and remodeling of cerebral arteriovenous malformation

    Directory of Open Access Journals (Sweden)

    Wang L

    2015-09-01

    Full Text Available Lingyan Wang,1 Shaolei Guo,2 Nu Zhang,2 Yuqian Tao,3 Heng Zhang,1 Tiewei Qi,2 Feng Liang,2 Zhengsong Huang2 1Department of Neurosurgery ICU, 2Department of Neurosurgery, 3Department of Neurology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, People’s Republic of China Background: Cerebral arteriovenous malformation (AVM involves the vasculogenesis of cerebral blood vessels and can cause severe intracranial hemorrhage. Stromal cell-derived factor-1 (SDF-1 and its receptor, CXCR4, are believed to exert multiple physiological functions including angiogenesis. Thus, we investigated the role of SDF-1/CXCR4 in the vasculogenesis of cerebral AVM.Methods: Brain AVM lesions from surgical resections were analyzed for the expression of SDF-1, CXCR4, VEGF-A, and HIF-1 by using immunohistochemical staining. Flow cytometry was used to quantify the level of circulating endothelial progenitor cells (EPCs. Further, in an animal study, chronic cerebral hypoperfusion model rats were analyzed for the expression of SDF-1 and HIF-1. CXCR4 antagonist, AMD3100, was also used to detect its effects on cerebral vasculogenesis and SDF-1 expression.Results: Large amounts of CXCR4-positive CD45+ cells were found in brain AVM lesion blood vessel walls, which also have higher SDF-1 expression. Cerebral AVM patients also had higher level of EPCs and SDF-1. In chronic cerebral hypoperfusion rats, SDF-1, HIF-1, and CD45 expressions were elevated. The application of AMD3100 effectively suppressed angiogenesis and infiltration of CXCR4-positive CD45+ cells in hypoperfusion rats compared to controls.Conclusion: The SDF-1/CXCR4 axis plays an important role in the vasculogenesis and migration of inflammatory cells in cerebral AVM lesions, possibly via the recruitment of bone marrow EPCs. Keywords: cerebral arteriovenous malformation, SDF-1/CXCR4, chronic cerebral hypoperfusion, endothelial progenitor cells

  14. Quantitative evaluation fo cerebrospinal fluid shunt flow

    Energy Technology Data Exchange (ETDEWEB)

    Chervu, S.; Chervu, L.R.; Vallabhajosyula, B.; Milstein, D.M.; Shapiro, K.M.; Shulman, K.; Blaufox, M.D.

    1984-01-01

    The authors describe a rigorous method for measuring the flow of cerebrospinal fluid (CSF) in shunt circuits implanted for the relief of obstructive hydrocephalus. Clearance of radioactivity for several calibrated flow rates was determined with a Harvard infusion pump by injecting the Rickham reservoir of a Rickham-Holter valve system with 100 ..mu..Ci of Tc-99m as pertechnetate. The elliptical and the cylindrical Holter valves used as adjunct valves with the Rickham reservoir yielded two different regression lines when the clearances were plotted against flow rats. The experimental regression lines were used to determine the in vivo flow rates from clearances calculated after injecting the Rickham reservoirs of the patients. The unique clearance characteristics of the individual shunt systems available requires that calibration curves be derived for an entire system identical to one implanted in the patient being evaluated, rather than just the injected chamber. Excellent correlation between flow rates and the clinical findings supports the reliability of this method of quantification of CSF shunt flow, and the results are fully accepted by neurosurgeons.

  15. Bacterial contamination of surgeons' gloves during shunt insertion; a pilot study

    DEFF Research Database (Denmark)

    Sørensen, Preben; Ejlertsen, Tove; Aaen, Dorte

    2008-01-01

    antibiotics and double gloving, by surgeons experienced in shunt surgery. Surgical incision, dissection and tunnelling were done. Then the surgeon, the scrub-nurse and, in three cases, the assistant made an imprint of their outer gloves on agar plates. Hereafter, they changed the outer pair of gloves before...... cultured from gloves in all 10 operations and coagulase-negative Staphylococci were found in eight operations. These results are preliminary, but nevertheless they are alarming. Despite the use of recommended precautions to avoid infections we found that a substantial numbers of gloves from surgeon, scrub...

  16. Comparison of laryngeal mask airway and endotreacheal intubation in ventriculoperitoneal shunt surgical anesthesia%双管喉罩置入与气管插管在脑室腹腔分流手术麻醉中的应用比较

    Institute of Scientific and Technical Information of China (English)

    陶伟平; 梁伟民

    2011-01-01

    Aim To compare the effects of respiration and circulation and complications of PRO-SEAL LMA laryngeal mask and endotra cheal intubation in patients with ventriculoperitoneal shunt surgery. Methods 43 patients, ASA Ⅱ -Ⅲ ,aged 23 - 67 years,who received surgery for ventriculoperitoneal shunt surgery under general anesthesia were randomly divided into PRO-SEAL LMA group( n = 22 )and tracheal intubation( TT)group( n = 21 ). MAP,HR,respiration system change and cerebral state index were recorded before induction of anesthesia( T1 ),immediately after intubation( T2 ),before extubation( T3 ),and immediately after extubation( T4 ). Adverse reactions dur ing extubation and the postsurgical complications were observed. Results MAP and HR were significantly higher in TT group than in LMA group at T2 ,T3, and T4( P < 0.01 ). There were significant differences between LMA group and TT group in VT, PAW, and PCL at T3( P < 0.01 ). There were significant differences between LMA group and TT group in cerebral state index at T3 and T4( P < 0.01 ). The incidence of body movement and coughing during extubation and that of postoperative gore throat and hoarse voice were higher in TT group than in LMA group( P < 0.01 ). Conclusions Laryngeal mask airway is better than endotreacheal intubation in patients undergo ing surgery for ventriculoperitoneal shunt. It is easier to maintain hemodynamic and respiration function stability and has fewer complica tions.%目的 比较PRO-SEAL LMA喉罩和气管插管用于脑室腹腔分流手术对患者呼吸循环和并发症的影响.方法 43例在全麻下实施脑室腹腔分流手术的患者,ASA Ⅱ~Ⅲ级,年龄23~67岁,随机被分为PRO-SEAL LMA喉罩组(LMA组)(n=22)和气管插管组(TT组)(n=21).分别记录麻醉前(T1)、插入喉罩/气管导管后即刻(T2)、拔管前即刻(T3)、拔管后即刻(T4)患者的平均动脉压、心率、呼吸系统变化、麻醉深度指数及两组拔管期的不良

  17. Rescue endoscopic third ventriculostomy for repeated shunt blockage

    Directory of Open Access Journals (Sweden)

    Puneet K Goyal

    2011-01-01

    Full Text Available The role of endoscopic third ventriculostomy (ETV is getting more popular for all types of hydrocephalus. It has several advantages and is also being considered for malfunctioning of ventriculo-peritoneal shunt. A 16-year-old child had fourteen shunt revisions in his life. He was eventually treated with ETV with successful result. Repeated shunt failure can be an additional indication of ETV.

  18. Major complication after intrauterine vesico-amniotic shunting

    Directory of Open Access Journals (Sweden)

    Springer Alexander

    2010-01-01

    Full Text Available Bilateral foetal uropathy is the leading cause of chronic renal failure in childhood. Vesico-amniotic shunting (VAS is a simple, feasible, and widely used procedure for decompressing the foetal urinary system. We report a case of a boy with bilateral foetal uropathy who underwent VAS at a gestational age of 29 weeks. Vesico-abdominal shunt dislodgement occurred and led to urinary ascites and anhydramnios. Postpartal laparotomy showed a shunt perforation between the urinary bladder and the peritoneal cavity.

  19. Ventriculoperitoneal shunt for intracranial hypertension in cryptococcal meningitis without hydrocephalus.

    Science.gov (United States)

    Petrou, Panayota; Moscovici, Samuel; Leker, Ronen R; Itshayek, Eyal; Gomori, John M; Cohen, José E

    2012-08-01

    The use of a ventriculoperitoneal (VP) shunt to treat uncontrollable intracranial hypertension in patients with cryptococcal meningitis without hydrocephalus is somewhat unusual and still largely unreported. However, uncontrollable intracranial hypertension without hydrocephalus in these patients is a potentially life-threatening condition. Early diagnosis and shunt placement are essential to improve survival and neurological function. We report uncontrollable intracranial hypertension without hydrocephalus in a 23-year-old woman, which was successfully managed by VP shunt placement.

  20. Morbidity and mortality after peritoneovenous shunt surgery for refractory ascites.

    OpenAIRE

    Rubinstein, D; McInnes, I; Dudley, F

    1985-01-01

    A prospective analysis of the morbidity and mortality after peritoneovenous shunting was carried out in 25 patients who had a total of 27 shunts for refractory ascites. Major complications were limited to the patients in whom ascites was secondary to hepatic rather than peritoneal disease. Immediate postoperative complications followed 17 out of the 23 shunts carried out in patients with liver disease and included septicaemia (two), profound hypotension (two), pulmonary oedema (one), and clin...

  1. Midterm Experience of Ipsilateral Axillary-Axillary Arteriovenous Loop Graft as Tertiary Access for Haemodialysis

    Directory of Open Access Journals (Sweden)

    J. P. Hunter

    2014-01-01

    Full Text Available Objectives. To present a series of ipsilateral axillary artery to axillary vein loop arm grafts as an alternative vascular access procedure for haemodialysis in patients with difficult access. Design. Retrospective case series. Methods. Patients who underwent an axillary loop arteriovenous graft from September 2009 to September 2012 were included. Preoperative venous imaging to exclude central venous stenosis and to image arm/axillary veins was performed. A cuffed PTFE graft was anastomosed to the distal axillary artery and axillary vein and looped on the arm. Results. 25 procedures were performed on 22 patients. Median age was 51 years, with 9 males and 13 females. Median number of previous access procedures was 3 (range 0–7. Median followup was 16.4 months (range 1–35. At 3 months and 1 year, the primary and secondary patency rates were 70% and 72% and 36% and 37%, respectively. There were 11 radiological interventions in 6 grafts including 5 angioplasties and 6 thrombectomies. There were 19 surgical procedures in 10 grafts, including thrombectomy, revision, repair for bleeding, and excision. Conclusions. Our series demonstrates that the axillary loop arm graft yields acceptable early patency rates in a complex group of patients but to maintain graft patency required high rates of surgical and radiological intervention, in particular graft thrombectomy.

  2. Ventriculoperitoneal shunt malfunction caused by proximal catheter fat obstruction.

    Science.gov (United States)

    Mizrahi, Cezar José; Spektor, Sergey; Margolin, Emil; Shoshan, Yigal; Ben-David, Eliel; Cohen, José E; Moscovici, Samuel

    2016-08-01

    Ventriculoperitoneal (VP) shunt placement is the mainstay of treatment for hydrocephalus, yet shunts remain vulnerable to a variety of complications. Although fat droplet migration into the subarachnoid space and cerebrospinal fluid pathways following craniotomy has been observed, a VP shunt obstruction with fat droplets has never been reported to our knowledge. We present the first reported case of VP shunt catheter obstruction by migratory fat droplets in a 55-year-old woman who underwent suboccipital craniotomy for removal of a metastatic tumor of the left medullocerebellar region, without fat harvesting. A VP shunt was inserted 1month later due to communicating hydrocephalus. The patient presented with gait disturbance, intermittent confusion, and pseudomeningocele 21days after shunt insertion. MRI revealed retrograde fat deposition in the ventricular system and VP shunt catheter, apparently following migration of fat droplets from the fatty soft tissue of the craniotomy site. Spinal tap revealed signs of aseptic meningitis. Steroid treatment for aseptic "lipoid" meningitis provided symptom relief. MRI 2months later revealed partial fat resorption and resolution of the pseudomeningocele. VP shunt malfunction caused by fat obstruction of the ventricular catheter should be acknowledged as a possible complication in VP shunts after craniotomy, even in the absence of fat harvesting.

  3. A compact, coaxial shunt current diagnostic for X pinches.

    Science.gov (United States)

    Wang, Liangping; Zhang, Jinhai; Li, Mo; Zhang, Xinjun; Zhao, Chen; Zhang, Shaoguo

    2015-08-01

    A compact coaxial shunt was applied in X-pinches experiments on Qiangguang pulsed power generator. The coaxial shunt was designed to have a compact construction for smaller inductance and more, for conveniently assembling upon the X pinch load structure. The coaxial shunt is also a cheap current probe and was easily built by research groups. The shunt can monitor a 100 kA high current with a 100 ns rise time. The calibration results showed that the probe used in the experiments has a resistance of 3.2 mΩ with an uncertainty of 3%, and its response time to the step signal is less than 7 ns.

  4. Superconducting fault current-limiter with variable shunt impedance

    Science.gov (United States)

    Llambes, Juan Carlos H; Xiong, Xuming

    2013-11-19

    A superconducting fault current-limiter is provided, including a superconducting element configured to resistively or inductively limit a fault current, and one or more variable-impedance shunts electrically coupled in parallel with the superconducting element. The variable-impedance shunt(s) is configured to present a first impedance during a superconducting state of the superconducting element and a second impedance during a normal resistive state of the superconducting element. The superconducting element transitions from the superconducting state to the normal resistive state responsive to the fault current, and responsive thereto, the variable-impedance shunt(s) transitions from the first to the second impedance. The second impedance of the variable-impedance shunt(s) is a lower impedance than the first impedance, which facilitates current flow through the variable-impedance shunt(s) during a recovery transition of the superconducting element from the normal resistive state to the superconducting state, and thus, facilitates recovery of the superconducting element under load.

  5. Emergency hepatectomy for hepatic arteriovenous malformation combined with pulmonary hypertension in an infant

    Directory of Open Access Journals (Sweden)

    Naruhiko Murase

    2015-12-01

    Full Text Available Patients with hepatic arteriovenous malformations rarely present with pulmonary hypertension. We report the case of a 3-month-old boy who developed severe pulmonary hypertension due to a hepatic arteriovenous malformation. The use of pulmonary vasodilators to treat the patient's pulmonary hypertension worsened his high-output heart failure. This is the first case in which emergency hepatectomy rescued a patient with hepatic arteriovenous malformations who developed pulmonary hypertension.

  6. Arteriovenous Fistula Complicated by Popliteal Venous Access for Endovascular Thrombolytic Therapy of Deep Vein Thrombosis

    Energy Technology Data Exchange (ETDEWEB)

    Byun, Sung Su; Kim, Jeong Ho; Park, Chul Hi; Hwang, Hee Young; Kim, Hyung SiK [Gacheon University Gil Medical Center, Gacheon (Korea, Republic of); Jeon, Young Sun; Kim, Won Hong [Inha University College of Medicine, Incheon (Korea, Republic of)

    2008-10-15

    We report a case of an iatrogenic arteriovenous fistula complicated by catheter- directed thrombolytic therapy in a patient with acute deep vein thrombosis of a lower extremity. To the best of our knowledge, this is the first report of an arteriovenous fistula between the sural artery and popliteal vein in that situation. As the vessels have a close anatomical relationship, the arteriovenous fistula seems to be a potential complication after endovascular thrombolytic therapy of acute deep vein thrombosis.

  7. Oculo-peritoneal shunt: draining aqueous humor to the peritoneum.

    Science.gov (United States)

    Maldonado-Junyent, Ana; Maldonado-Bas, Arturo; Gonzalez, Andrea; Pueyrredón, Francisco; Maldonado-Junyent, María; Maldonado-Junyent, Arturo; Rodriguez, Diego; Bulacio, Mariano

    2015-01-01

    In 2010, there were estimated to be approximately 60.5 million people with glaucoma. This number is expected to increase to 79.6 million by 2020. In 2010, there were 8.4 million people with bilateral blindness caused by glaucoma, and this number is expected in increase to 11.2 million by 2020. Filtering implants are special devices that have been developed to reduce intraocular pressure in patients with refractory glaucoma. The success rate of these implants is relatively low, and they continue to fail over time. To avoid failure caused by the formation of scar tissue around the implants, attempts have been made to drain the aqueous humor to various sites, including the venous system, lacrimal sac, sinuses, and conjunctival fornix. Recently, a system to shunt aqueous humor from the anterior chamber to the peritoneum has been developed. The surgical technique involved in this system is a modification of the technique currently used by neurosurgeons for the treatment of hydrocephalus. We present the first case operated using this technique.

  8. Ventriculoperitoneal shunt for hydrocephalus caused by central nervous system metastasis.

    Science.gov (United States)

    Lee, Seung Hoon; Kong, Doo Sik; Seol, Ho Joon; Nam, Do-Hyun; Lee, Jung-Il

    2011-09-01

    The development of better diagnostic tools and therapeutic modalities has increased the incidence of central nervous system (CNS) metastasis in malignant tumor patients. Hydrocephalus can result from CNS metastasis and frustrate cancer treatment. The authors sought to investigate the outcomes and the roles of ventriculoperitoneal shunts (VPS) in patients with CNS metastasis. The medical records of 50 consecutive patients who underwent VPS for hydrocephalus related to CNS metastasis were analyzed retrospectively. Data included features of primary malignancies, CNS involvement, clinical course and surgical outcome. Median patient age was 55.0 years (range 25-77), and 30 female and 20 male patients were included in the study. At the time of VPS, 10 patients had parenchymal metastases only and 40 patients had leptomeningeal seeding (LMS). Symptom improvement was observed postoperatively in 40 patients (80%), mean Karnofsky performance status (KPS) scale change was from 37.8 to 46.0, and median survival from VPS was 3.0 months (2 days to 54 months). A ventricular opening pressure of >30 cmH(2)O (HR 6.44, 95% CI 1.26-32.9, P = 0.02) and further cancer treatment after VPS (HR 0.17, 95% CI 0.07-0.42, P Hydrocephalus in CNS metastasis requiring VPS is commonly associated with LMS. VPS is an effective palliative measure and an adequate cancer treatment after VPS may provide the best means of improving survival.

  9. Oculo-peritoneal shunt: draining aqueous humor to the peritoneum

    Directory of Open Access Journals (Sweden)

    Ana Maldonado-Junyent

    2015-04-01

    Full Text Available In 2010, there were estimated to be approximately 60.5 million people with glaucoma. This number is expected to increase to 79.6 million by 2020. In 2010, there were 8.4 million people with bilateral blindness caused by glaucoma, and this number is expected in increase to 11.2 million by 2020. Filtering implants are special devices that have been developed to reduce intraocular pressure in patients with refractory glaucoma. The success rate of these implants is relatively low, and they continue to fail over time. To avoid failure caused by the formation of scar tissue around the implants, attempts have been made to drain the aqueous humor to various sites, including the venous system, lacrimal sac, sinuses, and conjunctival fornix. Recently, a system to shunt aqueous humor from the anterior chamber to the peritoneum has been developed. The surgical technique involved in this system is a modification of the technique currently used by neurosurgeons for the treatment of hydrocephalus. We present the first case operated using this technique.

  10. Rate of shunt revision as a function of age in patients with shunted hydrocephalus due to myelomeningocele.

    Science.gov (United States)

    Dupepe, Esther B; Hopson, Betsy; Johnston, James M; Rozzelle, Curtis J; Jerry Oakes, W; Blount, Jeffrey P; Rocque, Brandon G

    2016-11-01

    OBJECTIVE It is generally accepted that cerebrospinal fluid shunts fail most frequently in the first years of life. The purpose of this study was to describe the risk of shunt failure for a given patient age in a well-defined cohort with shunted hydrocephalus due to myelomeningocele (MMC). METHODS The authors analyzed data from their institutional spina bifida research database including all patients with MMC and shunted hydrocephalus. For the entire population, the number of shunt revisions in each year of life was determined. Then the number of patients at risk for shunt revision during each year of life was calculated, thus enabling them to calculate the rate of shunt revision per patient in each year of life. In this way, the timing of all shunt revision operations for the entire clinic population and the likelihood of having a shunt revision during each year of life were calculated. RESULTS A total of 655 patients were enrolled in the spina bifida research database, 519 of whom had a diagnosis of MMC and whose mean age was 17.48 ± 11.7 years (median 16 years, range 0-63 years). Four hundred seventeen patients had had a CSF shunt for the treatment of hydrocephalus and thus are included in this analysis. There were 94 shunt revisions in the 1st year of life, which represents a rate of 0.23 revisions per patient in that year. The rate of shunt revision per patient-year initially decreased as age increased, except for an increase in revision frequency in the early teen years. Shunt revisions continued to occur as late as 43 years of age. CONCLUSIONS These data substantiate the idea that shunt revision surgeries in patients with MMC are most common in the 1st year of life and decrease thereafter, except for an increase in the early teen years. A persistent risk of shunt failure was observed well into adult life. These findings underscore the importance of routine follow-up of all MMC patients with shunted hydrocephalus and will aid in counseling patients and

  11. Dependence of transcutaneous oxygen tension on local arteriovenous pressure gradient in normal subjects.

    Science.gov (United States)

    Wyss, C R; Matsen, F A; King, R V; Simmons, C W; Burgess, E M

    1981-05-01

    1. We studied the relationship between transcutaneous oxygen tension at the foot and local arteriovenous pressure difference in 15 normal men and women; arteriovenous pressure difference was varied by changing the height of the foot with respect to the heart and by applying external pressure to the foot. 2. Control transcutaneous oxygen tension was 67 +/- 9 SD mmHg (8.9 +/- 1.2 kPa) at a control arteriovenous pressure difference of 80 +/- 6 SD mmHg (10.6 +/- 0.8 kPa). 3. In every subject transcutaneous oxygen tension fell non-linearly with a decrease in arteriovenous pressure difference; transcutaneous oxygen tension was relatively insensitive to changes in arteriovenous pressure difference when arteriovenous pressure difference was high, but always fell sharply to zero at some positive arteriovenous pressure difference [range 13-34 mmHg (1.7-4.5 kPa)]. 4. An analysis of the data indicated that transcutaneous oxygen tension varied with arteriovenous pressure difference approximately as the oxygen tension of cutaneous venous blood under the sensor varied (in the absence of changes in cutaneous vascular resistance and oxygen consumption). 5. This analysis was supported by studies in three subjects in whom the oxygen tension of superficial venous drainage from a warmed hand or foot was measured along with transcutaneous oxygen tension while arteriovenous pressure difference was varied.

  12. Outcome of Kidney Allografts in Recipients With a Femoral Arteriovenous Fistula: Report of Two Cases

    Directory of Open Access Journals (Sweden)

    Denise M.D. Özdemir-van Brunschot

    2016-09-01

    Full Text Available Two patients, who were on hemodialysis over a femoral arteriovenous fistula, were transplanted in our center. Despite adequate blood pressure, perfusion of the renal allograft remained poor after completion of the vascular anastomoses. Ligation of the femoral arteriovenous fistula (1.6 L/min led to adequate perfusion. Initial graft function was good. Although it remains unclear whether ischemia of a renal allograft is caused by venous hypertension or vascular steal due to a femoral arteriovenous fistula, it might be necessary to ligate a femoral arteriovenous fistula to obtain adequate graft perfusion.

  13. Pressure drops in a distensible model of end-to-side anastomosis in systemic-to-pulmonary shunts.

    Science.gov (United States)

    Migliavacca, Francesco; Pennati, Giancarlo; Di Martino, Elena; Dubini, Gabriele; Pietrabissa, Riccardo

    2002-06-01

    The modified Blalock-Taussig shunt is a surgical procedure used as a palliation to treat complex congenital heart defects. It consists of an interposing prosthetic tube between the innominate/subclavian artery and the right pulmonary artery. Previous experience indicates that the pressure drop across the shunt is affected by the pulmonary pressure at the distal anastomosis combined with the distensibility of the anastomosis. In this study, a computational fluid-structure interaction approach is presented to investigate the haemodynamic behaviour. Steady-state fluid dynamics and structural analyses were carried out using commercial codes based on the finite element method (FIDAP and ABAQUS) coupled by means of a purposely-developed procedure to transfer boundary conditions. Both prosthetic tube and artery walls were characterised by non-linear material properties. Three different pulmonary pressures (2, 5 and 15 mmHg) and two volume flow rates (0.4 and 0.8 l/min) were investigated. Results indicate that the effects of distensibility at the distal anastomosis on the shunt pressure drop are relevant only when the distal anastomosis on the shunt pressure drop are relevant only when the distal anastomosis is not fully distended, which occurs when the pulmonary pressure is lower than 5 mmHg.

  14. Splenectomy and proximal lieno-renal shunt in a factor five deficient patient with extra-hepatic portal vein obstruction

    Directory of Open Access Journals (Sweden)

    Sahni Peush

    2006-05-01

    Full Text Available Abstract Background The clinico-surgical implication and successful management of a rare case of factor five (V deficiency with portal hypertension and hypersplenism due to idiopathic extra-hepatic portal venous obstruction is presented. Case presentation A 16-year old boy had gastro-esophageal variceal bleeding, splenomegaly and hypersplenism. During preoperative workup prolonged prothrombin time and activated partial thromboplastin time were detected, which on further evaluation turned out to be due to factor V deficiency. Proximal lieno-renal shunt and splenectomy were successfully performed with transfusion of fresh frozen plasma during and after the surgical procedure. At surgery there was no excessive bleeding. The perioperative course was uneventful and the patient is doing well on follow up. Conclusion Surgical portal decompressive procedures can be safely undertaken in clotting factor deficient patients with portal hypertension if meticulous surgical hemostasis is achieved at operation and the deficient factor is adequately replaced in the perioperative period.

  15. Novel current monitoring techniques without shunt resistors

    Directory of Open Access Journals (Sweden)

    VODA Adriana

    2012-05-01

    Full Text Available Current measurement for automotiveelectrical actuator applications (with motors or valvesis necessary for appropriate control in many cases anda safety requirement in all cases: the control algorithmmay be dependent on the data but safety relevantfunctions will use it to determine possible over-current,over-temperature or failure conditions. This paperproposes an alternative method of monitoring thecurrent, without using sensors or current shunts.Instead, measurements are made on the motor in thedevelopment stages and low/high frequency variationsin the supply line are monitored, through low/highpassfilters, by available AD channels in the system.This results in cost reduction for the final product, byreducing hardware complexity.

  16. An Unusual Case Of Urinary Bladder Arteriovenous Malformation

    LENUS (Irish Health Repository)

    Gnanappiragasam, D

    2016-07-01

    A 45-year-old male presented with haematuria and urinary frequency. Computed Tomography (CT) urogram revealed gross thickening of the left bladder wall. Histology showed large vessels cuffed by eosinophonilic material suggestive of urinary bladder arteriovenous malformation (AVM). No further intervention was carried out as symptoms resolve after the resection. Follow up rigid cystoscopy and CT at 3 months showed resolution of all visible pathology and no evidence of recurrence.

  17. Endovascular and microsurgical treatment of cerebral arteriovenous malformations: Current recommendations

    OpenAIRE

    Andrew Conger; Charles Kulwin; Lawton, Michael T; Cohen-Gadol, Aaron A.

    2015-01-01

    Background: Cerebral arteriovenous malformations (AVMs) can be a heterogeneous pathological entity whose management requires a complex decision-making process due to the risks associated with their treatment and natural history. Despite the recently published conclusions of the aborted Randomized Trial of Brain Unruptured AVMs (ARUBA) trial, the authors of this article believe multimodality intervention in general and microsurgical resection in particular continue to play a major role in the ...

  18. Arteriovenous fistula: An evidence based practice in nursing care

    OpenAIRE

    2013-01-01

    The arteriovenous fistula (AVF) is the most frequent form of vascular access for patients undergoing haemodialysis because it ensures good quality of dialysis and reduce haemodialysis mortality. For this reason, the nephrology nurse plays an important role in the appropriate care of fistula with a view to promoting the longevity and prevention of complications. Purpose: The purpose of this review was to investigate the role of Nephrology nurse in the appropriate care of fistula, promoting lon...

  19. Care of arteriovenous fistula by patients with chronic renal failure.

    OpenAIRE

    Monteiro Furtado, Angelina; Elisângela Teixeira Lima, Francisca

    2008-01-01

    This descriptive study aimed at identifying care of arteriovenous fistula (AVF) performed patients under hemodialysis. Twenty one hemodialysis patients were randomly selected in a clinic in Fortaleza, Ceara, Brazil:11 female and 11 male patients, age between 30 and 50 yearold, and most were single, retired, and had low education level. Semi-structured interview was applied. The following procedures were mentioned: cleaning the fistula arm, thrill palpation, avoiding lifting weight with AVF...

  20. Spontaneous knot; a rare cause of ventriculoperitoneal shunt blockage.

    LENUS (Irish Health Repository)

    Mohammed, Wail

    2011-02-01

    A 14-year old X linked congenital hydrocephalus presented with unexplained headaches and vomiting. He had external ventricular drain and intracranial pressure monitoring (ICP). Subsequently, he underwent exploration and removal of previously inserted ventriculoperitoneal (VP) shunts. On retrieval of peritoneal catheters a double knot was noted between his two distal catheters. This case illustrates a rare cause of ventriculoperitoneal shunt malfunction.

  1. Leakage Inductance Calculation for Planar Transformers with a Magnetic Shunt

    DEFF Research Database (Denmark)

    Jun, Zhang; Ouyang, Ziwei; Duffy, M. C.

    2013-01-01

    with a magnetic shunt by means of the stored magnetic energy in the primary and secondary sides of the transformer using the magnetomotive force (MMF) variation method, as well as the stored energy in the shunt based on the reluctance model. The detailed calculation method is described. Both the FEA simulation...

  2. Leakage Inductance Calculation for Planar Transformers with a Magnetic Shunt

    DEFF Research Database (Denmark)

    Zhang, Jun; Ouyang, Ziwei; Duffy, Maeve C.

    2014-01-01

    with a magnetic shunt by means of the stored magnetic energy in the primary and secondary sides of the transformer using the magnetomotive force (MMF) variation method, as well as the stored energy in the shunt based on the reluctance model. The detailed calculation method is described. Both the FEA simulation...

  3. Spontaneous knot; a rare cause of ventriculoperitoneal shunt blockage.

    LENUS (Irish Health Repository)

    Mohammed, Wail

    2012-02-01

    A 14-year old X linked congenital hydrocephalus presented with unexplained headaches and vomiting. He had external ventricular drain and intracranial pressure monitoring (ICP). Subsequently, he underwent exploration and removal of previously inserted ventriculoperitoneal (VP) shunts. On retrieval of peritoneal catheters a double knot was noted between his two distal catheters. This case illustrates a rare cause of ventriculoperitoneal shunt malfunction.

  4. Shunted-Josephson-junction model. II. The nonautonomous case

    DEFF Research Database (Denmark)

    Belykh, V. N.; Pedersen, Niels Falsig; Sørensen, O. H.

    1977-01-01

    The shunted-Josephson-junction model with a monochromatic ac current drive is discussed employing the qualitative methods of the theory of nonlinear oscillations. As in the preceding paper dealing with the autonomous junction, the model includes a phase-dependent conductance and a shunt capacitance...

  5. Syringomyelia regression after shunting of a trapped fourth ventricle

    Directory of Open Access Journals (Sweden)

    Dukagjin Morina

    2013-01-01

    Full Text Available We describe a case of progressive syringomyelia following post-infectious trapped fourth ventricle (TFV, which resolved after shunting of the fourth ventricle. A 28-year-old female who had previously undergone treatment of intracerebral hemorrhage and meningitis developed a hydrocephalus with TFV. After 3 years she developed disturbance of walking and coordination. Cranial-CT revealed an enlargement of the shunted fourth ventricle as a result of shunt dysfunction. Furthermore a cervical syringomyelia developed. The patient underwent a revision of a failed fourth ventriculo- peritoneal shunt. Postoperatively, syringomyelia resolved within 6 months and the associated neurological deficits improved significantly. An insufficiency of cerebrospinal fluid draining among patients with TFV can be associated with communicating syringomyelia. An early detection and treatment seems important on resolving syringomyelia and avoiding permanent neurological deficits. Ventriculo-peritoneal shunt in trapped fourth ventricles can resolve a secondary syringomyelia.

  6. Percutaneous peritoneovenous shunt positioning: technique and preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Orsi, Franco; Grasso, Rosario Francesco; Bonomo, Guido; Marinucci, Irene [Division of Radiology, European Institute of Oncology, Milan (Italy); Monti, Cinzia [Institute of Radiology, University of Milan (Italy); Bellomi, Massimo [Division of Radiology, European Institute of Oncology, Milan (Italy); Institute of Radiology, University of Milan (Italy)

    2002-05-01

    Nine peritoneovenous shunts were positioned by percutaneous technique in seven patients with advanced malignancy causing severe refractory ascites, and in two patients with hepatic cirrhosis (one with hepatocarcinoma). In all patients the shunts were percutaneously placed through the subclavian vein in the angiographic suite under digital fluoroscopic guide. No complications directly related to the procedure occurred. The shunt was successfully positioned in all patients in 60 min average time. No patient showed symptoms related to pulmonary overload or to disseminated intravascular coagulation. All patients had a significant improvement of the objective symptoms related to ascites such as respiratory symptoms, dyspepsia, and functional impairment to evacuation describing an improvement of their quality of life. Maximum shunt patency was 273 days. Percutaneous placement of peritoneovenous shunt is a safe, fast, and inexpensive procedure, extremely useful in resolution of refractory ascites, reducing symptoms, and allowing effective palliation, with a great improvement in quality of life. (orig.)

  7. The role of lumboperitoneal shunts in the treatment of syringomyelia.

    Science.gov (United States)

    Oluigbo, Chima O; Thacker, Karen; Flint, Graham

    2010-07-01

    OBJECT The role of thecoperitoneal shunts in the management of syringomyelia is not well defined. In this study, the authors analyze the outcome of lumboperitoneal shunt procedures carried out to treat syringomyelia in their institution. METHODS The authors retrospectively reviewed the medical records of 19 patients who underwent lumboperitoneal shunt procedures for syringomyelia. RESULTS The mean follow-up duration was 25 months (range 3-51 months). Of 16 cases followed up, only 5 patients reported clinical improvement in their preoperative symptoms, but of these, 2 had clear radiological evidence of improvement. Three of 6 patients with syringomyelia due to spinal arachnoiditis improved. CONCLUSIONS Lumboperitoneal shunts may lead to useful improvement in the symptoms of a patient with syringomyelia while avoiding the risk of neurological deterioration inherent in myelotomies required for syrinx shunting procedures.

  8. Flexural waves focusing through shunted piezoelectric patches

    Science.gov (United States)

    Yi, K.; Collet, M.; Ichchou, M.; Li, L.

    2016-07-01

    In this paper, we designed and analyzed a piezo-lens to focus flexural waves in thin plates. The piezo-lens is comprised of a host plate and piezoelectric arrays bonded on the surfaces of the plate. The piezoelectric patches are shunted with negative capacitance circuits. The effective refractive indexes inside the piezo-lens are designed to fit a hyperbolic secant distribution by tuning the negative capacitance values. A homogenized model of a piezo-mechanical system is adopted in the designing process of the piezo-lens. The wave focusing effect is studied by the finite element method. Numerical results show that the piezo-lens can focus flexural waves by bending their trajectories, and is effective in a large frequency band. The piezo-lens has the ability to focus flexural waves at different locations by tuning the shunting negative capacitance values. The piezo-lens is shown to be effective for flexural waves generated by different types of sources.

  9. Ventriculoperitoneal shunt infection with Listeria innocua.

    Science.gov (United States)

    Karli, Arzu; Sensoy, Gulnar; Unal, Nevzat; Yanik, Keramettin; Cigdem, Halit; Belet, Nursen; Sofuoglu, Ayse

    2014-08-01

    Listeria species may cause life-threatening events including meningitis and invasive infection in newborns, pregnant women, older and immunodeficient people. The most common Listeria species that causes infection is L. monocytogenes. It is known that Listeria innocua has no pathogenicity. A 9-month-old baby had ventriculoperitoneal shunt and was treated with adrenocorticotropic hormone because of infantile spasms. He was brought to hospital with fever and vomiting. Upon physical examination, the patient seemed uncomfortable and had a temperature of 38.6°C. Laboratory results were as follows: hemoglobin, 6.7 g/dL; leukocyte count, 5420/mm(3) ; platelet count, 169,000/mm(3) ; and C-reactive protein, 100 mg/L (normal <5 mg/L). On analysis of cerebrospinal fluid (CSF), leukocyte count was 480/mm(3) , protein was 46 mg/dL and CSF glucose was 35 mg/dL. L. innocua was isolated in CSF culture. We describe this unusual case of ventriculoperitoneal shunt infection with L. innocua.

  10. Parylene MEMS patency sensor for assessment of hydrocephalus shunt obstruction.

    Science.gov (United States)

    Kim, Brian J; Jin, Willa; Baldwin, Alexander; Yu, Lawrence; Christian, Eisha; Krieger, Mark D; McComb, J Gordon; Meng, Ellis

    2016-10-01

    Neurosurgical ventricular shunts inserted to treat hydrocephalus experience a cumulative failure rate of 80 % over 12 years; obstruction is responsible for most failures with a majority occurring at the proximal catheter. Current diagnosis of shunt malfunction is imprecise and involves neuroimaging studies and shunt tapping, an invasive measurement of intracranial pressure and shunt patency. These patients often present emergently and a delay in care has dire consequences. A microelectromechanical systems (MEMS) patency sensor was developed to enable direct and quantitative tracking of shunt patency in order to detect proximal shunt occlusion prior to the development of clinical symptoms thereby avoiding delays in treatment. The sensor was fabricated on a flexible polymer substrate to eventually allow integration into a shunt. In this study, the sensor was packaged for use with external ventricular drainage systems for clinical validation. Insights into the transduction mechanism of the sensor were obtained. The impact of electrode size, clinically relevant temperatures and flows, and hydrogen peroxide (H2O2) plasma sterilization on sensor function were evaluated. Sensor performance in the presence of static and dynamic obstruction was demonstrated using 3 different models of obstruction. Electrode size was found to have a minimal effect on sensor performance and increased temperature and flow resulted in a slight decrease in the baseline impedance due to an increase in ionic mobility. However, sensor response did not vary within clinically relevant temperature and flow ranges. H2O2 plasma sterilization also had no effect on sensor performance. This low power and simple format sensor was developed with the intention of future integration into shunts for wireless monitoring of shunt state and more importantly, a more accurate and timely diagnosis of shunt failure.

  11. The dilemma of complicated shunt valves: How to identify patients with posthemorrhagic hydrocephalus after aneurysmatic subarachnoid hemorrhage who will benefit from a simple valve?

    Directory of Open Access Journals (Sweden)

    Christian von der Brelie

    2016-01-01

    Full Text Available Background: Sophisticated shunt valves provide the possibility of pressure adjustment and antisiphon control but have a higher probability of valve dysfunction especially in a posthemorrhagic setting. The aim of the present study is to analyze the clinical outcome of patients with shunt dependent posthemorrhagic hydrocephalus after aneurysmatic subarachnoid hemorrhage (SAH in order to identify patients who would benefit from a simple differential pressure valve. Methods: From 2000 to 2013, 547 patients with aneurysmatic SAH were treated at our institution, 114 underwent ventricular shunt placement (21.1%. 47 patients with available pre- and post-operative computed tomography scans, and an available follow-up of minimum 6 months were included. In order to measure the survival time which a nonprogrammable differential pressure valve would have had in an individual patient we defined the initial equalized shunt survival time (IESS. IESS is the time until surgical revisions of fixed differential pressure or flow-regulated valves for the treatment of over- or under-drainage as well as re-programming of adjustable valves due to over- or under-drainage. Results: Twenty patients were treated with fixed differential pressure valves, 15 patients were treated with flow-regulated valves, and 12 underwent ventriculoperitoneal (VP shunt placement with differential pressure valves assisted by a gravitational unit. Patients who reacted with remarkable changes of the ventricular width after the insertion of external ventricular drainage (EVD, before shunt placement, showed a significantly longer IESS. Conclusions: Decline of the ventricular width after EVD placement was a predictor for successful VP shunt therapy in the later course of disease. Possibly, this could allow identifying patients who benefit from a simple differential pressure valve or a flow-regulated valve, and thus could possibly avoid valve-associated complications of a programmable valve in the

  12. The transjugular portosystemic stent shunt (TIPSS) as an intervention in clinical complication of portal hypertension; Der transjugulaere portosystemische Stentshunt (TIPSS) als Intervention bei klinischen Komplikationen der portalen Hypertonie

    Energy Technology Data Exchange (ETDEWEB)

    Thalhammer, A.; Jacobi, V.; Schwarz, W.; Balzer, J.; Abolmaali, N.; Vogl, T.J. [Frankfurt Univ. (Germany). Zentrum der Radiologie

    2001-10-01

    Most frequent complications in patients with liver cirrhosis are due to portal hypertension. Beside ascites circumvent vessles formate with vasodilatation. Due to counterregulation a secondary hyperaldosteronism develops with release of vasocontrictive agents. If conservative and endoscopic methods fail, indication for building a portosystemic shunt is given. The TIPSS procedure is less invasive than the surgical method of Warren-Shunt, so the radiological intervention has replaced surgery. Reducing the portal pressure by the shunt, the clinical complications change for the better. Still problems are defined as hepatic encephalopathy and right ventricular heart failure. Regular follow up investigations have to be performed to detect complications in the shunt. Using regular clinical and radiological check up TIPSS is of clinical benefit with good long term results. (orig.) [German] Die haeufigsten Komplikationen bei Patienten mit einer Leberzirrhose lassen sich auf das Vorliegen einer portalen Hypertension zurueckfuehren. Neben einer Aszitesbildung kommt es zur Vasodilatation mit Ausbildung portaler Umgehungskreislaeufe, gegenregulatorisch zu einem sekundaeren Hyperaldosteronismus und Ausschuettung vasokonstriktiver Substanzen. Sind mittels konservativer und endoskopischer Methoden die Komplikationen nicht mehr zu beherrschen, ist die Indikation zur Shuntanlage gegeben. Wegen der geringeren Invasivitaet einer TIPSS-Anlage gegenueber der operativen Methode eines Warren-Shunts hat sich die interventionell radiologische Methodik in den letzten Jahren immer mehr durchgesetzt. Durch den mittels Shuntanlage reduzierten Pfortaderdruck kommt es zu einer deutlichen klinischen Besserung der unterschiedlichen Komplikationen. Als klinisch problematische Symptome bei der Shuntanlage sind die hepatische Enzephalopathie und eine Zunahme der Rechtsherzbelastung zu werten. Um Komplikationen im Bereich des Shunts frueh zu erkennen, muss dieser engmaschig kontrolliert werden. Unter

  13. Value of embolization of brain arteriovenous malformations with ethylene vinyl alcohol copolymer

    Institute of Scientific and Technical Information of China (English)

    YANG Xin-xin; SONG Lu; WU Na; LIU Zhen-guo

    2010-01-01

    @@ T° the Editor We are interested in a recent article "Embolization of brain arteriovenous malformations with ethylene vinyl alcohol copolymer: technical aspects" written by GAO et al.1 Ethylene vinyl alcohol copolymer (Onyx) is a novel liquid embolic material used to cure brain arteriovenous malformations. They performed the embolization on 115 patients and they found that the complications of the treatment are scarce.

  14. Concurrent Pancreatic Head and Tail Arteriovenous Malformations in a 40-Year-Old Gentleman: The First Published Report

    Directory of Open Access Journals (Sweden)

    Asma Alnajjar

    2014-05-01

    Full Text Available Context Pancreatic arteriovenous malformations (AVMs are uncommon in the gastrointestinal tract. Less than 100 cases have been identified in the medical literature. Approximately 10% of all pancreatic AVMs are sporadic. Case Report Herein, we report the first documented case of sporadic concurrent pancreatic head and tail AVMs in a 40-year-old gentleman who presented with a 10-day history of epigastric pain and one episode of hematemesis. Patient denied any history of traumatic incidents, cigarette smoking, alcohol abuse, chronic gastric/duodenal ulcer, chronic pancreatitis, chronic hepatic disease, difficulty swallowing, respiratory compromise, or weight loss. Physical examination and laboratory results were unremarkable. Contrast-enhanced computed tomography scan showed two hypervascular masses involving the pancreatic head and tail. The celiac trunk angiogram showed proliferating vascular networks involving the pancreatic head and tail. The superior mesenteric angiogram demonstrated significant vascular contribution to the pancreatic head arteriovenous malformation only. Due to the extreme locations of pancreatic AVMs in the head and tail, surgical resection of both lesions(leaving behind the normal pancreatic body was not possible. Instead, patient underwent intraoperative irradiation therapy (IORT. During the procedure, patient was surgically operated to retract healthy organs/tissues, and then a single concentrated dose of radiation therapy was precisely applied to both pancreatic head and tail AVM lesions. Patient had an uneventful postoperative recovery and was discharged home on the second postoperative day in stable condition. The patient is to be seen in clinic in a 4-month-period during which patient will be completing a 12-month period of postoperative IORT. Conclusion This is the first documented case of sporadic concurrent pancreatic head and tail AVMs. Angiography is the gold standard diagnostic modality.

  15. Ventriculoatrial Shunt for Infantile Hydrocephalus%脑室心房引流术治疗小儿脑积水

    Institute of Scientific and Technical Information of China (English)

    陈张根; 郑瑞森; 金百祥

    1983-01-01

    Ventriculoatrial shunt was employed in treating 13 cases of infantile hydroencephalus at our department from Apr.,1979 to Aug., 1981. Model NJS-6 infantile hydrocephalus shunting device (made in Shanghai) was applied. Follow-ups (missed in 3 cases) which lasted 1-34 months showed that 6 patients were alive and well. Among them, 5 were normal or approximately normal in in-tellegence. 4 died either of the said condition or of other diseases.Also discussed are the diagnosis, surgical approach, postoperative care and complications.%@@ 自五十年代末带瓣硅胶管应用于脑室心房引流术获得成功以来,脑积水的手术治疗取得进展(1、2).

  16. Spastic Paraparesis Due to a Spinal Arachnoid Cyst Associated with Herniation of Cerebellar Tonsils After a Ventriculoperitoneal Shunt

    Directory of Open Access Journals (Sweden)

    Nargess Afzali

    2009-01-01

    Full Text Available  Secondary intradural arachnoid cysts involving the spine are uncommon and can be due to trauma, surgery, lumbar puncture, intrathecal injection and arachnoiditis (TB meningitis, chemical meningitis. Caudal dislocation of the cerebellar tonsils may be associated with known clinical conditions such as intracranial mass lesions or Chiari I and II malformations. It may also be acquired after repeated lumbar punctures or lumboperitoneostomy and traumatic CSF leaks. In rare cases it is reported after supratentorial shunting. "nHere a 16 year old boy is presented with progressive spastic paraparesis 18months after a ventriculoperitoneal shunt. Brain MRI revealed acquired post surgical cerebellar herniation and the spinal MRI showed a large intradural arachnoid cyst. TB laboratory tests were negative. Laminectomy, cyst drainage and suboccipsital craniectomy were performed. Despite the surgery, the disease progression continued to severe paraparesis. 

  17. Evaluation of Shunt Losses in Industrial Silicon Solar Cells

    Directory of Open Access Journals (Sweden)

    P. Somasundaran

    2016-01-01

    Full Text Available Shunting is one of the key issues in industrial silicon solar cells which degrade cell performance. This paper presents an approach for investigation of the performance degradation caused by the presence of ohmic extended shunts at various locations in industrial silicon solar cells. Location, nature, and area of the shunts existing in solar cells have been examined by lock-in infrared thermography (LIT. Based on LIT images and experimental dark I-V curves of solar cell, shunted cell has been modeled, from which loss in fill factor and efficiency due to the specific shunt has been obtained. Distributed diode modeling approach of solar cell has been exploited for obtaining simulation results which were supported by experimental measurements. The presented approach is useful to estimate performance reduction due to specific shunts and to quantify losses, which can help in improving the efficiency of solar cell during production by tackling the shunt related problems based on the level of severity and tolerance.

  18. A plasma polymerization technique to overcome cerebrospinal fluid shunt infections.

    Science.gov (United States)

    Cökeliler, D; Caner, H; Zemek, J; Choukourov, A; Biederman, H; Mutlu, M

    2007-03-01

    Prosthetic devices, mainly shunts, are frequently used for temporary or permanent drainage of cerebrospinal fluid. The pathogenesis of shunt infection is a very important problem in modern medicine and generally this is characterized by staphylococcal adhesion to the cerebrospinal fluid shunt surfaces. In this paper, the prevention of the attachment of test microorganism Staphylococcus epidermidis on the cerebrospinal fluid shunt surfaces by 2-hydroxyethylmethacrylate (HEMA) precursor modification in the plasma polymerization system, is reported. Different plasma polymerization conditions (RF discharge power 10-20-30 W, exposure time 5-10-15 min) were employed during the surface modification. The surface chemistry and topology of unmodified and modified shunts was characterized by x-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Also, static contact angle measurements were performed to state the change of surface hydrophilicity. All samples were tested in vitro with Staphylococcus epidermidis. A plasma-polymerized HEMA film (PP HEMA) was found to be an alternative simple method to decrease the microorganism attachment and create bacterial anti-fouling surfaces. The attachment of the model microorganism Staphylococcus epidermidis on the shunt surface modified by PP HEMA at 20 W and 15 min was reduced 62.3% if compared to the unmodified control surface of the shunt.

  19. A plasma polymerization technique to overcome cerebrospinal fluid shunt infections

    Energy Technology Data Exchange (ETDEWEB)

    Coekeliler, D [Plasma Aided Bioengineering and Biotechnology Research Laboratory, Engineering Faculty, Hacettepe University, 06532, Ankara (Turkey); Caner, H [Department of Neurosurgery, School of Medicine, Baskent University, 06610, Ankara (Turkey); Zemek, J [Institute of Physics, Academy of Sciences of the Czech Republic, Cukrovarnicka 10, 162 53, Prague, Czech Republic (Czech Republic); Choukourov, A [Department of Macromolecular Physics, Charles University, V Holesovickach 2, 18000 Prague (Czech Republic); Biederman, H [Department of Macromolecular Physics, Charles University, V Holesovickach 2, 18000 Prague (Czech Republic); Mutlu, M [Plasma Aided Bioengineering and Biotechnology Research Laboratory, Engineering Faculty, Hacettepe University, 06532, Ankara (Turkey)

    2007-03-01

    Prosthetic devices, mainly shunts, are frequently used for temporary or permanent drainage of cerebrospinal fluid. The pathogenesis of shunt infection is a very important problem in modern medicine and generally this is characterized by staphylococcal adhesion to the cerebrospinal fluid shunt surfaces. In this paper, the prevention of the attachment of test microorganism Staphylococcus epidermidis on the cerebrospinal fluid shunt surfaces by 2-hydroxyethylmethacrylate (HEMA) precursor modification in the plasma polymerization system, is reported. Different plasma polymerization conditions (RF discharge power 10-20-30 W, exposure time 5-10-15 min) were employed during the surface modification. The surface chemistry and topology of unmodified and modified shunts was characterized by x-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Also, static contact angle measurements were performed to state the change of surface hydrophilicity. All samples were tested in vitro with Staphylococcus epidermidis. A plasma-polymerized HEMA film (PP HEMA) was found to be an alternative simple method to decrease the microorganism attachment and create bacterial anti-fouling surfaces. The attachment of the model microorganism Staphylococcus epidermidis on the shunt surface modified by PP HEMA at 20 W and 15 min was reduced 62.3% if compared to the unmodified control surface of the shunt.

  20. The advantages of balloon assistance in endovascular embolization of spinal dural arteriovenous fistulas.

    Science.gov (United States)

    Cohen, José E; Moscovici, Samuel; Itshayek, Eyal

    2013-01-01

    Endovascular embolization is accepted as an alternative to surgical management of spinal dural arteriovenous fistulas (DAVF) in most patients; however, when the feeder vessel arises from the trunk vessel with an acutely angled origin, microcatheter navigation may be difficult, hazardous, and sometimes impossible. We propose a technique that eases microguidewire engagement and microcatheterization of arteries that arise at very acute angles with the assistance of a parallel compliant balloon that acts as supporter, guider, and protector. This technique was successfully applied in three consecutive patients with spinal DAVF with unfavorable vascular anatomy that limited selective microcatheterization. The balloon supports and guides the microguidewire along the feeder (supportive role). The balloon can then be placed at the origin of the feeder vessel and inflated during embolization to prevent liquid agent reflux (protective role). Use of this technique as a first option reduces procedure time and radiation exposure. A limiting factor is the need for a relatively large working channel to allow the combined use of a balloon and a microcatheter.

  1. Use of intracranial and ocular thermography before and after arteriovenous malformation excision

    Science.gov (United States)

    Hwang, Peter Y. K.; Lewis, Philip M.; Maller, Jerome J.

    2014-11-01

    Excision of arteriovenous malformations (AVMs) is known to carry a risk of postoperative hemorrhage, postulated to be the result of normal perfusion pressure breakthrough. It is also possible that AVMs may cause a steal effect, reducing perfusion in nearby vessels. There is currently no simple method of visualizing the presence or absence of steal effect intraoperatively. We hypothesized that the infrared thermographic (heat sensitive) imaging of perilesional brain may be useful for detecting reduced perfusion due to steal. Moreover, we hypothesized that if steal effect was present, it could impact on ocular perfusion and thereby temperature. Our objective was, therefore, to investigate whether perilesional cortical and ocular temperature (OT) may be a marker of steal effect. We intraoperatively acquired conventional and thermal images of the surgical field and eyes bilaterally, pre- and post-excisions of a large left hemisphere AVM. We found OT asymmetry preoperatively, which was absent after the AVM was excised. Intraoperative thermal images showed an increase of perilesional temperature, although this could be confounded by generalized changes in cortical perfusion due to anesthetics or surgery.

  2. Return to the emergency department after ventricular shunt evaluation.

    Science.gov (United States)

    Sarda, Samir; Simon, Harold K; Hirsh, Daniel A; Wang, Andrew; Shane Tubbs, R; Chern, Joshua J

    2016-04-01

    OBJECT Patients with CSF shunts are medically complex and frequently present to the emergency department (ED) with suspected shunt malfunction. After adequate evaluation in the ED and proper disposition, some patients return to the ED within a short period of time. In this study, the authors examined the reasons for ED revisits within 7 days of the index ED visit to discern possible preventable returns. METHODS There were 3080 index ED visits made by patients with shunted hydrocephalus between 2010 and 2013. Index ED visits preceded by another ED visit or neurosurgical procedure within 60 days were excluded. Index ED visits for reasons unrelated to shunt function and those that led directly to admissions and shunt revision surgeries were also excluded. The remaining 1509 ED visits were eligible for analysis in this study. Final dispositions from the index ED visit included home (1176 cases), admission to the neurosurgery service for observation (134 cases), and admission to other services (199 cases). Subsequent events within 7 days, including ED revisits, hospital admissions, and shunt-related surgery were recorded, and reasons for the ED revisits were categorized based on whether the visit was related to shunt function concerns. Clinical and socioeconomic factors were analyzed for their association with ED revisits by using statistical methods. RESULTS Of the 1176 patients discharged home from the ED after shunt function evaluation, 101 (8.6%) returned to the ED within 7 days. Of the 134 patients admitted to the neurosurgery service for observation only, 8 (6.0%) returned to the ED within 7 days of discharge. Of the 199 patients admitted to hospital services other than neurosurgery, 13 (6.5%) returned to the ED within 7 days of discharge. The reasons for ED revisits vary (total of 122 visits combining the 3 groups), but at least 60% of the revisits were clearly unrelated to shunt function. A younger age, daytime arrival to the ED, and living within the

  3. Ion beam sputter-etched ventricular catheter for hydrocephalus shunt

    Science.gov (United States)

    Banks, B. A. (Inventor)

    1983-01-01

    A cerebrospinal fluid shunt in the form of a ventricular catheter for controlling the condition of hydrocephalus by relieving the excessive cerebrospinal fluid pressure is described. A method for fabrication of the catheter and shunting the cerebral fluid from the cerebral ventricles to other areas of the body is also considered. Shunt flow failure occurs if the ventricle collapse due to improper valve function causing overdrainage. The ventricular catheter comprises a multiplicity of inlet microtubules. Each microtubule has both a large openings at its inlet end and a multiplicity of microscopic openings along its lateral surfaces.

  4. Power System Harmonic Compensation Using Shunt Active Power Filter.

    Directory of Open Access Journals (Sweden)

    Shiuly Mukherjee

    2014-07-01

    Full Text Available This paper shows the method of improving the power quality using shunt active power filter. The proposedtopic comprises of PI controller, filter hysteresis current control loop, dc link capacitor. The switching signal generation for filter is fromhysteresis current controller techniques. With the all these element shunt active power filter reduce the total harmonic distortion. Thispaper represents the simulation and analysis of the using three phase three wire system active filter to compensate harmonics .Theproposed shunt active filter model uses balanced non-linear load. This paper successfully lowers the THD within IEEE norms and satisfactorily works to compensatecurrent harmonics.

  5. Pollutants removal in subsurface infiltration systems by shunt distributing wastewater with/without intermittent aeration under different shunt ratios.

    Science.gov (United States)

    Pan, Jing; Yuan, Fang; Zhang, Yang; Huang, Linli; Yu, Long; Zheng, Fanping; Cheng, Fan; Zhang, Jiadi

    2016-10-01

    Matrix dissolved oxygen (DO), removal of COD, TP and nitrogen in subsurface infiltration systems (SISs), named SIS A (without intermittent aeration and shunt distributing wastewater), SIS B (with shunt distributing wastewater) and SIS C (with intermittent aeration and shunt distributing wastewater) were investigated. Aerobic conditions were developed in 50cm depth and anoxic or anaerobic conditions were not changed in 80 and 110cm depth by intermittent aeration. Under appropriate shunt ratios, shunt distributing wastewater improved denitrification and had little influence on COD, TP and NH3-N removal. Under the optimal shunt ratio of 1:2 for SIS C, high average removal rates of COD (90.06%), TP (93.17%), NH3-N (88.20%) and TN (85.79%) were obtained, which were higher than those in SIS A (COD: 82.56%, TP: 92.76%, NH3-N: 71.08%, TN: 49.24%) and SIS B (COD: 81.12%, TP: 92.58%, NH3-N: 69.14%, TN: 58.73%) under the optimal shunt ratio of 1:3.

  6. [Surgical treatment of chiasmal gliomas in children].

    Science.gov (United States)

    Helcl, F

    1997-03-01

    Chiasmal gliomas are rare brain tumors occurring especially in children. Their proper treatment is still controversial and consists of surgery, radiotherapy and chemotherapy. Surgical removal of these tumors can usually be only partial or subtotal and radiotherapy frequently follows. There are supporters of surgical approach, as well as its enemies. The author has been engaged in problems of optimal treatment of this entity for more than 10 years. He is offering a review of knowledge from the literature concerning surgical treatment of this disease in children. The great majority of articles in the literature are dealing with retrospective analysis of relatively small series of patients usually treated in single neurosurgical department and the surgical treatment is enclosed like a part of combined therapy. Articles dealing only with surgical treatment of chiasmal gliomas are few and reviews determining the contemporary role of surgery of this entity are also lacking. This was the main impulse for writing this compilation. The short history of surgical therapy is reviewed. Some new trends of this therapy are also mentioned (microsurgery, Cavitron Ultrasonic Surgical Aspirator and peroperative use of visual evoked potentials). Up to date criteria for surgical treatment of chiasmal gliomas in children are given-exploration of chiasmal region and performing a biopsy in all cases, radical surgery only in extrinsic gliomas of the chiasmal region and conservative surgical approach to intrinsic chiasmal gliomas. It is emphasized that the significance of obstructive hydrocephalus in this entity has not been fully estimated till now, as well as the role of shunting procedures. Surgical treatment remains, nevertheless, an important armamentarium in the management of chiasmal gliomas in children. (Ref. 20.)

  7. The effect of ligation of the distal vein in snuff-box arteriovenous fistula

    Directory of Open Access Journals (Sweden)

    Beigi Ali

    2009-01-01

    Full Text Available Arterio-venous fistula (AVF in the snuff-box region is one of the current techniques used for creating a vascular access in patients undergoing dialysis. The aim of this study is to find out whether ligating the distal vein in AVF in the snuff-box will bring about any change in the efficiency and complications of the fistula. Sixty patients (30 males, 30 females suffering from chronic renal failure, who had been admitted for creating an AVF, were randomly divided into two groups after having filled out consent forms. After the AVF was made, the distal vein was ligated in the first group, but not in the second group. The patients were discharged after being given the necessary advice on how to take care of their fistula. They were examined on post-surgical days 1, 30 and 90. Early efficiency in the ligated and non-ligated groups was 100% and 96.7% respectively while late efficiency in the two groups was 90% and 83.4%, respectively (P > 0.05. The most common complication in both groups was thrombosis (11.7%. Venous hypertension and edema were observed in two patients (both from the non-ligated group and infection of the surgical site was observed in only one patient. Our study suggests that, considering the high efficiency level and low complication rate, AVF at the snuff-box region constitutes one of the best possible vascular accesses for patients undergoing hemodialysis. Ligation of the distal vein prevents the development of venous hypertension in the fistula.

  8. Preliminary Clinical Observation of Arteriovenous Sheathotomy for Treatment of Branch Retinal Vein Occlusion

    Institute of Scientific and Technical Information of China (English)

    Lin Lu; Yonghao Li; Changxian Yi; Mei Li; Xiulan Lu; Jinglin Zhang

    2003-01-01

    Purpose: To document the anatomic and functional improvement of six patients withbranch retinal vein occlusion (BRVO) following successful arteriovenous adventitialsheathotomy (AAS).Methods: Retrospective study of 6 patients (6 eyes) with BRVO treated with AAS. Allpatients were not eligible for laser photocoagulation and had both macular edema andintraretinal hemorrhage. The visual acuity was in the range of 0.4 to 0.02. All patientsunderwent pars plana vitrectomy and AAS. The clinical improvement was determined byfundus photograph, fluorescein angiography (FAG), optical coherence tomography(OCT) and multifocal electroretinography (ERG). All patients were followedpostoperatively for an average of 20 months ranging from 12 to 24 months.Results: Sheathotomy and decompression of the arteriole/venule (A/V) crossing wereachieved in all 6 patients. 5 patients have improved their best-corrected visual acuity 4lines or more. The best one could reach to 1.0. One month after the operation, fundusphotograph and FAG demonstrated the resolution of intraretinal hemorrhage, reduction ofnon-perfusion area and apparent resolution of retinal venous dilation and tortuosity. OCTconfirmed remarkable reduction of retinal thickness. The microcysts at the foveadiminished. Multifocal ERG showed the recovery of the central peak at the macular andthe peripheral response density. However, capillary nonperfusion area andmicroaneurysm were found out by FAG in four patients at the points distal to thesheathotomy three months after the operation.Conclusions: Anatomic and functional improvement of retina can be achieved in patientswith BRV0 through AAS. However, the capillary nonperfusion and microaneurysm mayfollow this surgical procedure in some cases that need further treatment with laserphotocoagulation. The better visual improvement may be expected in the patients withearlier surgical intervention.

  9. Eruption of blood: Arteriovenous malformation of the penile urethra

    Science.gov (United States)

    White, Joshua T.; Baverstock, Richard J.

    2017-01-01

    While arteriovenous malformations (AVMs) are a common congenital or post-traumatic abnormality, male genital AVMs are rare and have been described in the scrotum or penis in pediatric patients.1,2 We describe a 34-year-old male presenting with recurrent spontaneous penile urethral bleeding found to have an AVM of the penile urethra. While angiography has traditionally been helpful, magnetic resonance imaging (MRI) can aid in the diagnosis and characterization of these lesions.3 Each case of male genital AVM provides a unique challenge to manage depending on the presenting complaint, as there are no guidelines to direct treatment.4 PMID:28163810

  10. Novalis Stereotactic Radiosurgery for Spinal Dural Arteriovenous Fistula.

    Science.gov (United States)

    Sung, Kyoung-Su; Song, Young-Jin; Kim, Ki-Uk

    2016-07-01

    The spinal dural arteriovenous fistula (SDAVF) is rare, presenting with progressive, insidious symptoms, and inducing spinal cord ischemia and myelopathy, resulting in severe neurological deficits. If physicians have accurate and enough information about vascular anatomy and hemodynamics, they achieve the good results though the surgery or endovascular embolization. However, when selective spinal angiography is unsuccessful due to neurological deficits, surgery and endovascular embolization might be failed because of inadequate information. We describe a patient with a history of vasospasm during spinal angiography, who was successfully treated by spinal stereotactic radiosurgery using Novalis system.

  11. [Arteriovenous fistula in patients with a complicated postphlebitic syndrome].

    Science.gov (United States)

    Quiñones Castro, M; Fernández de la Vara Sánchez, L; Perera González, F; Alvarez Sánchez, J A

    1991-01-01

    An investigation, which goal is to evidencing AV fistulas in patients with a complicated postthrombotic syndrome, as well as to determinate the efficacy of noninvasive methods used for the study of AV fistulas in such patients, is presented. So, patients with a complicated postphlebitic syndrome interned into the Instituto de Angiología were studied. Twenty-five patients were included in the study, 9 of these patients (36%) had arteriovenous fistulas, arteriographically evidenced. Haemodynamic study do not support the evidence of such communications.

  12. Arteriovenous malformation within an isocitrate dehydrogenase 1 mutated anaplastic oligodendroglioma

    Directory of Open Access Journals (Sweden)

    Grace Lai

    2015-01-01

    Full Text Available Background: The co-occurrence of intracranial arteriovenous malformations (AVMs and cerebral neoplasms is exceedingly rare but may harbor implications pertaining to the molecular medicine of brain cancer pathogenesis. Case Description: Here, we present a case of de novo AVM within an isocitrate dehydrogenase 1 mutated anaplastic oligodendroglioma (WHO Grade III and review the potential contribution of this mutation to aberrant angiogenesis as an interesting case study in molecular medicine. Conclusion: The co-occurrence of an IDH1 mutated neoplasm and AVM supports the hypothesis that IDH1 mutations may contribute to aberrant angiogenesis and vascular malformation.

  13. Combined arteriovenous thrombolytic infusion for refractory renal vein thrombosis.

    Science.gov (United States)

    Heafner, Thomas A; Scott, Daniel; Watson, J Devin; Propper, Brandon; Johnson, Chatt; Arthurs, Zachary M

    2014-08-01

    Acute renal vein thrombosis can rapidly lead to significant impairment and eventual loss of renal function. Classically presenting with flank pain, hematuria, and laboratory markers consistent with acute kidney injury, therapeutic anticoagulation is the mainstay of treatment. However, endovascular surgery offers a safe and effective alternative for renal salvage in the setting of acute renal vein thrombosis. Described is the use of combined arteriovenous thrombolytic infusion for refractory renal vein thromboses to quickly and effectively decrease clot burden in the micro- and macrovenous circulations while limiting systemic exposure.

  14. Posterior cranial fossa arteriovenous fistula with presenting as caroticocavernous fistula

    Energy Technology Data Exchange (ETDEWEB)

    Liu, H.M.; Shih, H.C.; Huang, Y.C.; Wang, Y.H. [Dept. of Medical Imaging, National Taiwan University Hospital, Taipei (Taiwan)

    2001-05-01

    We report cases of posterior cranial fossa arteriovenous fistula (AVF) with presenting with exophthalmos, chemosis and tinnitus in 26- and 66-year-old men. The final diagnoses was vertebral artery AVF and AVF of the marginal sinus, respectively. The dominant venous drainage was the cause of the unusual presentation: both drained from the jugular bulb or marginal sinus, via the inferior petrosal and cavernous sinuses and superior ophthalmic vein. We used endovascular techniques, with coils and liquid adhesives to occlude the fistulae, with resolution of the symptoms and signs. (orig.)

  15. Classical Triad in Pulmonary Arteriovenous Malformation: Clubbing, Cyanosis and Policytemia

    Directory of Open Access Journals (Sweden)

    Hikmet Tekin Nacaroğlu

    2013-08-01

    Full Text Available Pulmonary arteriovenous malformations (PAVM are generally congenital lesions that results from an abnormal capillary development. Lesions can be presented as an isolated single anomaly, or may be multiple when accompanying with autosomal dominant hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber Syndrome; ROWS. These cases may be asymptomatic, but exertional dyspnea, palpitations and easy fatigability may also be seen. The classic radiological appearance is a round, well-circumscribed lesions. Computed tomography of thorax and angiography are also useful for diagnosis. Herein, we present 2 and 13 years old girls with the diagnosis of PAVM with clubbing and cyanosis. (Journal of Current Pediatrics 2013;11:92-5

  16. Intracranial dural arterio-venous fistula presenting with progressive myelopathy.

    LENUS (Irish Health Repository)

    Ogbonnaya, Ebere Sunny

    2011-01-01

    Spinal dural arterio-venous fistula (DAVF) is rare and usually involves the thoracic segments. The classical presentation is a slowly progressive ataxia. Clinical presentation of intracranial DAVF depends on the site of the DAVF, as well as the vessels involved. Patients may present with pulsatile tinnitus, occipital bruit, headache, dementia, visual impairment as well as neurological deterioration distant from the DAVF as a result of venous hypertension and cortical haemorrhage. The authors present a rare case of progressive myelopathy secondary to an intracranial DAVF.

  17. Uterine Arteriovenous Malformation with Sudden Heavy Vaginal Hemmorhage

    Directory of Open Access Journals (Sweden)

    Marianne Haughey

    2013-09-01

    Full Text Available Dysfunctional uterine bleeding (DUB is a common presentation in the emergency department and has a wide differential. Most presentations of DUB are in hemodynamically stable patients and can be evaluated as an outpatient. Uterine arteriovenous malformation (AVM is one presentation that can result in a life-threatening medical emergency with unexpected sudden and massive vaginal bleeding. We describe a case of a 24-year-old female with sudden heavy vaginal bleeding requiring a blood transfusion, ultrasound evidence of uterine AVM, and a treatment method of expectant management using an intrauterine device in an attempt to preserve fertility. [West J Emerg Med. 2013;14(5:411-414.

  18. Delayed postoperative dural arteriovenous fistula presenting with progressive dementia.

    Science.gov (United States)

    Higashida, Tetsuhiro

    2015-12-09

    A 64-year-old woman underwent right suboccipital craniotomy to treat spontaneous cerebrospinal fluid (CSF) otorrhoea. Although the CSF leak was cured, the patient developed pulsatile tinnitus, ambulatory disturbance and progressive dementia. Four years after the surgery, she presented with generalised seizure. Cerebral angiography showed a dural arteriovenous fistula at the right transverse-sigmoid sinus, which was associated with sinus occlusion, retrograde blood flow in the sinus and diffuse intracranial cortical venous reflux. A combination of endovascular transarterial embolisation and transvenous embolisation with direct sinus puncture was performed. After the procedure, the patient's mental status and cognitive function improved significantly.

  19. The Retrograde Ventriculosinusal Shunt in an Animal Experimental Model of Hydrocephalus.

    Science.gov (United States)

    Pinto, Fernando Campos Gomes; Becco, Rodrigo; Alho, Eduardo Joaquim Lopes; Poli-de-Figueiredo, Luiz Francisco; Souza, Podalyro Amaral de; Oliveira, Matheus Fernandes de; Teixeira, Manoel Jacobsen

    2016-01-01

    Currently, hydrocephalus treatment is performed mainly with ventriculoperitoneal shunting. This experimental study aims at assessing whether the experimental model of hydrocephalus in dogs is applicable to the laboratory study of the retrograde ventriculosinusal shunt (RVSS). Four mongrel dogs were assessed. After randomization, the animals were divided into two groups: an experimental group that underwent the induction of hydrocephalus/RVSS and a control group, for the measurement of the mean arterial pressure, intracranial pressure and pressure in the superior sagittal sinus (SSS). The controls presented a mean arterial pressure of 68 mm Hg (71 and 65), an intracranial pressure of 163 mm H2O (149.6 and 176.8) and a pressure at the SSS of 40 mm H2O (40 and 40). The kaolin injection into the cisterna magna at a concentration of 0.3 mg/ml was capable of inducing the clinical and radiological mechanism of hydrocephalus (intracranial pressure = 250 mm H2O, pressure at the SSS = 50 mm H2O). The caliber of the SSS was 2.5 ± 1.0 mm. The fact that the SSS caliber of the dog was the same size as the external diameter of the catheter used resulted in the complete obstruction of the SSS when the catheter was inserted. We believe we could design and perform an experimental model to test the RVSS. It is applicable and feasible. The model of hydrocephalus, the surgical apparatus and the scenario were adequate, but the shunt system needs to be proportionally made to the canine anatomy.

  20. Clopidogrel in infants with systemic-to-pulmonary-artery shunts

    DEFF Research Database (Denmark)

    Wessel, David L; Berger, Felix; Li, Jennifer S

    2013-01-01

    BACKGROUND: Infants with cyanotic congenital heart disease palliated with placement of a systemic-to-pulmonary-artery shunt are at risk for shunt thrombosis and death. We investigated whether the addition of clopidogrel to conventional therapy reduces mortality from any cause and morbidity related...... to the shunt. METHODS: In a multicenter, double-blind, event-driven trial, we randomly assigned infants 92 days of age or younger with cyanotic congenital heart disease and a systemic-to-pulmonary-artery shunt to receive clopidogrel at a dose of 0.2 mg per kilogram of body weight per day (467 infants...... days of age. RESULTS: The rate of the composite primary end point did not differ significantly between the clopidogrel group (19.1%) and the placebo group (20.5%) (absolute risk difference, 1.4 percentage points; relative risk reduction with clopidogrel, 11.1%; 95% confidence interval, -19.2 to 33.6; P...

  1. Effects of an interatrial shunt on rest and exercise hemodynamics

    DEFF Research Database (Denmark)

    Kaye, David; Shah, Sanjiv J; Borlaug, Barry A

    2014-01-01

    BACKGROUND: A treatment based on an interatrial shunt device has been proposed for counteracting elevated pulmonary capillary wedge pressure (PCWP) in patients with heart failure and mildly reduced or preserved ejection fraction (HFpEF). We tested the theoretical hemodynamic effects...... of the conditions tested. CONCLUSIONS: The interatrial shunt reduced left-sided cardiac output with a marked reduction in PCWP. This approach may reduce the propensity for heart failure exacerbations and allow patients to exercise longer, thus attaining higher heart rates and cardiac outputs with the shunt compared...... of this approach with the use of a previously validated cardiovascular simulation. METHODS AND RESULTS: Rest and exercise hemodynamics data from 2 previous independent studies of patients with HFpEF were simulated. The theoretical effects of a shunt between the right and left atria (diameter up to 12 mm) were...

  2. Factors affecting ventriculoperitoneal shunt survival in adult patients

    Directory of Open Access Journals (Sweden)

    Farid Khan

    2015-01-01

    Conclusions: Patients with increased age, prolonged hospital stay, GCS score of less than 13, extra-ventricular drains in situ, or excision of brain tumors were more likely to experience early shunt malfunction.

  3. Digital implementation of shunting-inhibitory cellular neural network

    Science.gov (United States)

    Hammadou, Tarik; Bouzerdoum, Abdesselam; Bermak, Amine

    2000-05-01

    Shunting inhibition is a model of early visual processing which can provide contrast and edge enhancement, and dynamic range compression. An architecture of digital Shunting Inhibitory Cellular Neural Network for real time image processing is presented. The proposed architecture is intended to be used in a complete vision system for edge detection and image enhancement. The present hardware architecture, is modeled and simulated in VHDL. Simulation results show the functional validity of the proposed architecture.

  4. In vitro flow measurements in ion sputtered hydrocephalus shunts

    Science.gov (United States)

    Cho, Y. I.; Back, L. H.

    1989-01-01

    This paper describes an experimental procedure for accurate measurements of the pressure-drop/flow rate relationship in hydrocephalus shunts. Using a fish-hook arrangement, small flow rates in a perforated ion-sputtered Teflon microtubule were measured in vitro in a pressured system and were correlated with pressure in the system. Results indicate that appropriate drainage rates could be obtained in the physiological range for hydrocephalus shunts.

  5. Cross-species functionality of pararetroviral elements driving ribosome shunting.

    Directory of Open Access Journals (Sweden)

    Mikhail M Pooggin

    Full Text Available BACKGROUND: Cauliflower mosaic virus (CaMV and Rice tungro bacilliform virus (RTBV belong to distinct genera of pararetroviruses infecting dicot and monocot plants, respectively. In both viruses, polycistronic translation of pregenomic (pg RNA is initiated by shunting ribosomes that bypass a large region of the pgRNA leader with several short (sORFs and a stable stem-loop structure. The shunt requires translation of a 5'-proximal sORF terminating near the stem. In CaMV, mutations knocking out this sORF nearly abolish shunting and virus viability. METHODOLOGY/PRINCIPAL FINDINGS: Here we show that two distant regions of the CaMV leader that form a minimal shunt configuration comprising the sORF, a bottom part of the stem, and a shunt landing sequence can be replaced by heterologous sequences that form a structurally similar configuration in RTBV without any dramatic effect on shunt-mediated translation and CaMV infectivity. The CaMV-RTBV chimeric leader sequence was largely stable over five viral passages in turnip plants: a few alterations that did eventually occur in the virus progenies are indicative of fine tuning of the chimeric sequence during adaptation to a new host. CONCLUSIONS/SIGNIFICANCE: Our findings demonstrate cross-species functionality of pararetroviral cis-elements driving ribosome shunting and evolutionary conservation of the shunt mechanism. We are grateful to Matthias Müller and Sandra Pauli for technical assistance. This work was initiated at Friedrich Miescher Institute (Basel, Switzerland. We thank Prof. Thomas Boller for hosting the group at the Institute of Botany.

  6. Hearing Loss in Patients with Shunt-Treated Hydrocephalus.

    Science.gov (United States)

    Panova, Margarita V; Geneva, Ina E; Madjarova, Kalina I; Bosheva, Miroslava N

    2015-01-01

    Hearing loss is a common manifestation of the long-term complications in patients with shunt treated hydrocephalus along with motor development disturbance, cognitive and visual impairment, epilepsy and endocrine disorders. The aim of the present study was to investigate the alterations of hearing in patients with shunt treated hydrocephalus of non-tumor etiology and at least one year after implantation of ventriculo-peritoneal shunt, as well as their impact on the quality of life of patients. The study included 70 patients (age range 1.25 years - 21.25 years) with shunted non-tumor hydrocephalus and at least one year after placement of the shunt system. Hearing alterations were proved by measuring the brainstem auditory evoked potentials (BAEP) for children up to 5 years of age and children with mental retardation; audiograms was used for children older than 5 years with normal neuro-psychological development (NPD). Of the 70 studied patients 17 (24%) had hearing loss (10 bilateral and 7-unilateral) and all of them had sensorineural hearing loss, which is associated with low weight at birth, posthemorrhagic hydrocephalus and brainstem symptoms at the time of diagnosis of hydrocephalus. Hearing pathology was found more often in shunt-treated patients with NPD retardation, poor functional status and low quality of life. Children with shunt-treated hydrocephalus have hearing loss of sensorineural type. Children with brain stem symptomatology at diagnosing hydrocephalus and children with post-hemorrhagic hydrocephalus show higher risk of hearing loss. Children with shunted hydrocephalus and hearing loss show lower NPD, lower quality of life and lower functional status.

  7. Ventriculoperitoneal shunt infection with Mycobacterium fortuitum: a rare offending organism.

    Science.gov (United States)

    Cadena, Gilbert; Wiedeman, Jean; Boggan, James E

    2014-12-01

    Postsurgical infection is one of the greatest potential morbidities of ventriculoperitoneal shunt surgery. The majority of infections can be linked to contamination with skin flora at the time of surgery, a phenomenon that has been well described. However, there is a paucity of literature regarding infection with nontuberculous mycobacteria. The authors report a case of postoperative ventriculoperitoneal shunt infection with Mycobacterium fortuitum and review the available neurosurgical literature and treatment strategies.

  8. Calibration of piezoelectric RL shunts with explicit residual mode correction

    Science.gov (United States)

    Høgsberg, Jan; Krenk, Steen

    2017-01-01

    Piezoelectric RL (resistive-inductive) shunts are passive resonant devices used for damping of dominant vibration modes of a flexible structure and their efficiency relies on the precise calibration of the shunt components. In the present paper improved calibration accuracy is attained by an extension of the local piezoelectric transducer displacement by two additional terms, representing the flexibility and inertia contributions from the residual vibration modes not directly addressed by the shunt damping. This results in an augmented dynamic model for the targeted resonant vibration mode, in which the residual contributions, represented by two correction factors, modify both the apparent transducer capacitance and the shunt circuit impedance. Explicit expressions for the correction of the shunt circuit inductance and resistance are presented in a form that is generally applicable to calibration formulae derived on the basis of an assumed single-mode structure, where modal interaction has been neglected. A design procedure is devised and subsequently verified by a numerical example, which demonstrates that effective mitigation can be obtained for an arbitrary vibration mode when the residual mode correction is included in the calibration of the RL shunt.

  9. Triggerless vacuum shunting plasma by metallic and solid materials

    Science.gov (United States)

    Yukimura, Ken; Tani, Yuuji; Masamune, Sadao

    2000-10-01

    Shunting discharge is an alternating capacitor discharge through a rod of solid-state or metallic materials. Optimization of the discharge condition has realized self-ignition of the arc discharge with low input power to the rod, leading to a much longer rod life time than in conventional shunting arc or peripheral arc. The shunting-arc-produced plasma contains mainly the ions of the solid-state material, and ion extraction from the plasma has also been demonstrated. Thus, the shunting arc works as a pulsed ion source for solid-state materials for plasma-based ion implantation (PBII) and ion processing. This article describes the characteristics of pulsed shunting arc, using the materials of carbon, niobium and silicon. The capacitor of 10 nF of which charging voltage is 10 to 25 kV using a thyratron as a closing switch. Glow discharge is firstly produced after the heat of the materials and then the plasma changes the style to the arc discharge. A negative high voltage pulse of -5 to -10 kV was applied to a target which was located at 30 cm away from the electrodes. We will discuss the ion species of the shunting plasma and ion extraction from the plasma using the time evolution of target current.

  10. The utility of the plain radiograph ''shunt series'' in the evaluation of suspected ventriculoperitoneal shunt failure in pediatric patients

    Energy Technology Data Exchange (ETDEWEB)

    Desai, Kapil R.; Babb, James S.; Amodio, John B. [New York University School of Medicine, Department of Radiology, Pediatric Radiology Section, New York, NY (United States)

    2007-05-15

    To our knowledge, the sensitivity of plain radiography, known as the shunt series, in diagnosing an etiology of ventriculoperitoneal (VP) shunt malfunction in children has not been previously investigated. To determine the accuracy of plain radiography in diagnosing VP shunt failure in children in whom shunt malfunction is clinically suspected. We retrospectively reviewed the charts of 238 children who had undergone plain radiographic examination for evaluation of clinically suspected VP shunt failure over a 5-year period. The results were compared with those of CT, MRI, and nuclear cisternography. Just 6.72% of patients demonstrated plain radiographic signs of shunt failure. Of patients with normal plain radiographs, 43% demonstrated shunt abnormalities on CT, MRI or cisternography. Statistical analysis indicated that no more than 10.46% (P < 0.05) of plain radiographs showed signs of failure and that the sensitivity of plain radiography for the detection of VP shunt failure is no higher than 31%. Furthermore, there was poor agreement between the results of plain radiography and those of CT, MRI and cisternography. Children with clinically suspected VP shunt failure should proceed directly to cross-sectional or nuclear imaging, as plain radiographic examinations have low sensitivity and significant false-negative rates for detecting shunt abnormalities in all-comers. Use of the shunt series should be limited to patients who specifically have suspected mechanical causes of shunt failure. (orig.)

  11. Endophthalmitis: a rare complication of arteriovenous fistula infection.

    Science.gov (United States)

    Desai, Madhav; Rapoor, Ram; Gudithi, Swarna Latha; Kumar, Ravi; Prasad, Neela; Dakshinamurty, Kaligotla Venkata

    2008-04-01

    Vascular access infection is a frequent problem in patients undergoing maintenance hemodialysis. Infection of arteriovenous fistula (AVF) is less common than dialysis catheter-associated infection. Previous case reports described endophthalmitis secondary to hemodialysis catheter-related infection, but not secondary to native AVF infection. We report a rare patient of endophthalmitis as a metastatic infection of AVF cannulation site abscess. A 19-year-old girl on maintenance hemodialysis for the past 2 years has presented with a history of fever, chills, and rigor of 3-days duration and painful dimness of vision in the left eye of 1-night duration. It was followed by redness of the eye, photophobia, and ocular discharge. On examination, the patient was febrile with an abscess near cannulation site of AVF. There was no perception of light in the left eye, conjunctiva was congested, cornea was clear, hypopyon present, and pupil was mid-dilated, not reacting to light. Lens was clear. Vitreitis and exudative retinal detachment was present. Methicillin sensitive Staphylococcus aureus was isolated from blood, pus from AVF abscess and vitreous fluid. Diagnosis of endophthalmitis was confirmed by B-scan ultrasound. She was treated with both intravenous and intraocular antibiotics and drainage of pus from AVF abscess and therapeutic vitrectomy. Though arteriovenous abscess responded to sensitive antibiotics and drainage, vision has not improved much. Strict aseptic precautions during regular AVF cannulation are required. Lapses may lead to loss of vision apart from described complications like access closure, endocarditis, and osteomyelitis.

  12. [Arachnoid cysts of the middle cranial fossa in children. A review of 75 cases, 47 of which have been operated in a comparative study between membranectomy with opening of cisterns and cystoperitoneal shunt].

    Science.gov (United States)

    Lena, G; Erdincler, P; Van Calenberg, F; Genitori, L; Choux, M

    1996-01-01

    The authors report their experience concerning 75 cases of middle fossa arachnoid cysts observed in children during the period 1975-1993, 47 of which (62.6%) were operated upon. The aim of this study was to study the clinical presentation of these cysts, to discuss the surgical indications and to compare the results of the various techniques used to treat these malformations. Head injury was revealing in 17 cases (22.6%) and among these, 12 patients presented intracranial complications (subdural effusions; 6 cases, subdural hematomas: 4 cases and intracystic hematomas: 2 cases). The most usual signs and symptoms were: intracranial hypertension (25.3%), epilepsy (16%) and temporal bulging (24%). Twenty-one patients (44.7%) underwent a cystoperitoneal shunt; 20 patients (42.5%) were treated by membranectomy with opening of the basal cisterns and removal of intracystic (2 cases) or subdural hematoma (4 cases); 2 patients (4.3%) were treated using membranectomy, opening of the cisterns and cystoperitoneal shunt and 4 patients (8.4%) underwent a subduroperitoneal shunt. The long-term results were good regardless of the surgical procedure; nevertheless, only one patient among 20 cases treated by membranectomy and opening of the cisterns developped complications (5%), while multiple shunt revisions were necessary in 11 children (40.7%) out of 27 where a shunt was inserted. The authors conclude that membranectomy and opening of the basal cisterns is the procedure of choice to treat middle fossa arachnoid cysts in children.

  13. Analysis of related factors affecting prognosis of shunt surgery in patients with secondary normal pressure hydrocephalus

    Directory of Open Access Journals (Sweden)

    WANG Cheng

    2013-08-01

    Full Text Available 【Abstract】Objective: The management of se-condary normal pressure hydrocephalus (sNPH is controversial. Many factors may affect the surgery effect. The purpose of this study was to identify the possible fac-tors influencing prognosis and provide theoretical basis for clinical treatment of sNPH. Methods: A retrospective study was carried out to investigate the results of 31 patients with sNPH who under-went ventriculoperitoneal shunt surgery from January 2007 to December 2011. We processed the potential influencing factors by univariate analysis and the result further by mul-tivariate logistic regression analysis. Results: Factors including age, disease duration and Glasgow coma scale (GCS score before surgery significantly influenced the prognosis of sNPH (P<0.05. Further logistic regression analysis showed that all the three factors are independent influencing factors. Conclusion: Age, disease duration and GCS score before surgery have positive predictive value in estimating favorable response to surgical treatment for sNPH. Key words: Hydrocephalus, normal pressure; Ventriculoperitoneal shunt; Regression analysis

  14. Surgical Management of Stuttering Ischemic Priapism: A Case Report and Concise Clinical Review

    Science.gov (United States)

    Raslan, M.; Hiew, K.; Hoyle, A.; Ross, D.G.; Betts, C.D.; Maddineni, S.B.

    2016-01-01

    Stuttering priapism is an extremely rare and poorly understood entity. We present a rare case of a 47-year-old Afro-Caribbean gentleman who required proximal shunt procedure to treat his ischemic stuttering priapism after he had failed medical management. We provided a concise review of the literature on the surgical management of ischemic priapism. This case highlighted the importance of prompt surgical intervention in prolonged stuttering priapism to avoid serious psychological and functional complications. PMID:26977408

  15. Surgical therapy for portal hypertension in patients with cirrhosis in China: present situation and prospects

    Institute of Scientific and Technical Information of China (English)

    ZHOU Guang-wen; LI Hong-wei

    2009-01-01

    @@ Surgical therapy for portal hypertension (PHT) in patients with cirrhosis has long been controversial,and various operative approaches have been used to prevent or manage such lethal complications as gastroesophageal variceal hemorrhage. However, over a century various portazygos devascularization and shunt approaches have been developed or modified, but the therapeutic effects have not been satisfactory till 1963 when Starzl did the first liver transplantation in the world, which provides a new hope to the surgical treatment of PHT.

  16. [A case of repeated shunt malfunctions with eosinophilic meningitis caused by silicone allergy].

    Science.gov (United States)

    Kambara, Mizuki; Miyazaki, Takeshi; Yoshikane, Tsutomu; Sugimoto, Keiji; Akiyama, Yasuhiko

    2014-12-01

    The ventricular-peritoneal shunt for hydrocephalus is a well-known and established method but is sometimes complicated by shunt malfunction due to several causes. Eosinophilic meningitis is a rare disease, but has occasionally been reported as a cause of shunt malfunction. Here, we report the case of a 74-year-old woman with repeated shunt malfunction and eosinophilic meningitis due to a silicone allergy. Originally, the patient received a ventricular-peritoneal shunt for normal pressure hydrocephalus secondary to subarachnoid hemorrhage. However, shunt malfunction was identified 6 weeks later, and the first shunt revision was performed using a new shunt system from a different company. Further evaluation to identify the cause of the shunt malfunction revealed no abnormal findings, except for eosinophilia in the serum and cerebrospinal fluid. A second shunt malfunction was identified 16 weeks after the first shunt revision. We therefore concluded that eosinophilic meningitis caused by a silicone allergy might be the real culprit and a second shunt revision was performed using a silicone "extracted" tube. Since then, the patient's course has been free from shunt malfunction. In this case, the serum and cerebrospinal fluid eosinophilia were useful markers for identifying the cause of repeated shunt malfunctions. The silicone "extracted" tube may be helpful for diagnosis and therapy.

  17. The use of 4D-CTA in the diagnostic work-up of brain arteriovenous malformations

    Energy Technology Data Exchange (ETDEWEB)

    Willems, Peter W.A. [Toronto Western Hospital, UHN, Division of Neuroradiology, Department of Medical Imaging, Toronto, Ontario (Canada); Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Taeshineetanakul, Patamintita; Terbrugge, Karel G.; Krings, Timo [Toronto Western Hospital, UHN, Division of Neuroradiology, Department of Medical Imaging, Toronto, Ontario (Canada); Schenk, Barry; Brouwer, Patrick A. [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands)

    2012-02-15

    We aimed to evaluate the use of time-resolved whole-head CT angiography (4D-CTA) in patients with an untreated arteriovenous malformation of the brain (bAVM), as demonstrated by catheter angiography (DSA). Seventeen patients with a DSA-proven bAVM were enrolled. These were subjected to 4D-CTA imaging using a 320 detector row CT scanner. Using a standardized scoring sheet, all studies were analyzed by a panel of three readers. This panel was blind to the DSA results at the time of reading the 4D-CTA. 4D-CTA detected all bAVMs. With regard to the Spetzler-Martin grade, 4D-CTA disagreed with DSA in only one case, where deep venous drainage was missed. Further discrepancies between 4D-CTA and DSA analyses included underestimation of the nidus size in small lesions (four cases), misinterpretation of a feeding vessel (one case), misinterpretation of indirect feeding through pial collaterals (three cases) and oversight of mild arterial enlargement (two cases). 4D-CTA correctly distinguished low-flow from high-flow lesions and detected dural/transosseous feeding (one case), venous narrowing (one case) and venous pouches (nine cases). In this series, 4D-CTA was able to detect all bAVMs. Although some angioarchitectural details were missed or misinterpreted when compared to DSA, 4D-CTA evaluation was sufficiently accurate to diagnose the shunt and classify it. Moreover, 4D-CTA adds cross-sectional imaging and perfusion maps, helpful in treatment planning. 4D-CTA appears to be a valuable new adjunct in the non-invasive diagnostic work-up of bAVMs and their follow-up when managed conservatively. (orig.)

  18. “Large Animal Model of Pumpless Arteriovenous Extracorporeal CO2 Removal Using Room Air Via Subclavian Vessels”

    Science.gov (United States)

    Witer, Lucas; Howard, Ryan; Trahanas, John; Bryner, Benjamin S.; Alghanem, Fares; Hoffman, Hayley R.; Cornell, Marie S.; Bartlett, Robert H.; Rojas-Peña, Alvaro

    2016-01-01

    End-stage lung disease (ESLD) causes progressive hypercapnia, dyspnea, and impacts quality of life. Many extracorporeal support (ECS) configurations for CO2 removal resolve symptoms but limit ambulation. An ovine model of pumpless ECS using subclavian vessels was developed to allow for ambulatory support. Vascular grafts were anastomosed to the left subclavian vessels in four healthy sheep. A low-resistance membrane oxygenator was attached in an arteriovenous (AV) configuration. Device function was evaluated in each animal while awake and spontaneously breathing, and while mechanically ventilated with hypercapnia induced. Sweep gas (FiO2=0.21) to the device was increased from 0-15 L/min and arterial and post-device blood gases, as well as post-device air, were sampled. Hemodynamics remained stable with average AV shunt flows of 1.34±0.14 L/min.. In awake animals, CO2 removal was 3.4±1.0 mL/kg/min at maximum sweep gas flow. Respiratory rate decreased from 60±25 at baseline to 30±11 breaths per minute. In animals with induced hypercapnia, PaCO2 increased to 73.9±15.1. At maximum sweep gas flow, CO2 removal was 3.4±0.4 mL/kg/min and PaCO2 decreased to 49.1±6.7 mmHg. Subclavian AV access is effective in lowering PaCO2 and respiratory rate, and is potentially an effective ambulatory destination therapy for ESLD patients. PMID:26461241

  19. Intrahepatic arterioportal shunt: helical CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Quiroga, S.; Sebastia, M.C.; Moreiras, M.; Pallisa, E.; Rius, J.M.; Alvarez-Castells, A. [I. D. I. Hospital General i Universitari Vall d`Hebron, Barcelona (Spain). Servei de Radiodiagnostic

    1999-08-01

    The purpose of this study was to characterize the appearance of intrahepatic arterioportal shunts (APS) on two-phase helical CT, with emphasis on the importance of the hepatic arterial-dominant phase (HAP) to demonstrate perfusion disorders. We review eight cases of APS diagnosed by helical CT in our institution from January 1996 to March 1997 and describe the CT findings that established diagnosis. Five of them were confirmed by angiography. In seven (87.5 %) cases of APS we found early enhancement of the peripheral portal branches during the HAP of helical CT, whereas the superior mesenteric and splenic veins remained unenhanced. In five (62.5 %) cases of APS, transient, peripheral, triangular parenchymal enhancement was depicted during the HAP of helical CT; in four of these cases there was associated early enhancement of the portal branches. Helical CT can show perfusion alterations that might remain undiagnosed with conventional CT. An understanding of the hemodynamic changes that occur in APS can help in the interpretation of focal transient hepatic parenchymal enhancement and to differentiate APS from hypervascular tumors. We believe that the helical CT findings described herein are characteristic enough to suggest the diagnosis of APS. (orig.) With 3 figs., 1 tab., 16 refs.

  20. Transjugular Intrahepatic Portosystemic Shunt for Maintenance of Portal Venous Patency in Liver Transplant Candidates

    Directory of Open Access Journals (Sweden)

    Ron Charles Gaba

    2013-01-01

    Full Text Available Maintenance of portal venous patency is vital to liver transplant candidates, as the presence of portal vein thrombosis (PVT adversely impacts clinical outcomes by increasing surgical complexity and decreasing postoperative survival. By enhancing portal venous blood flow, transjugular intrahepatic portosystemic shunt (TIPS creation may enable clearance of PVT and preservation of portal venous patency in cirrhotic patients. Herein, we describe four cases in which TIPS produced and sustained an open portal venous system in liver transplant candidates with partial PVT. All patients demonstrated rapid and effective flow-enabled clearance of clot and intermediate to long-term preservation of portal venous flow. On this basis, we propose that maintenance of portal venous patency in liver transplant candidates with partial PVT represents a developing indication for TIPS.

  1. Analysis of related factors affecting prognosis of shunt surgery in patients with secondary normal pressure hydrocephalus

    Institute of Scientific and Technical Information of China (English)

    WANG Cheng; DU Hang-gen; YIN Li-chun; HE Min; ZHANG Guo-jun; TIAN Yong; HAO Bi-lie

    2013-01-01

    Objective:The management of secondary normal pressure hydrocephalus (sNPH) is controversial.Many factors may affect the surgery effect.The purpose of this study was to identify the possible factors influencing prognosis and provide theoretical basis for clinical treatment of sNPH.Methods:A retrospective study was carried out to investigate the results of 31 patients with sNPH who underwent ventriculoperitoneal shunt surgery from January 2007 to December 2011.We processed the potential influencing factors by univariate analysis and the result further by multivariate logistic regression analysis.Results:Factors including age,disease duration and Glasgow coma scale (GCS) score before surgery significantly influenced the prognosis of sNPH (P<0.05).Further logistic regression analysis showed that all the three factors are independent influencing factors.Conclusion:Age,disease duration and GCS score before surgery have positive predictive value in estimating favorable response to surgical treatment for sNPH.

  2. Ventriculoperitoneal shunt in a patient with ruptured blister aneurysm treated with pipeline embolization device.

    Science.gov (United States)

    Tan, Lee A; Gerard, Carter S; Keigher, Kiffon M; Moftakhar, Roham; Lopes, Demetrius K

    2015-03-01

    Cerebral spinal fluid (CSF) diversion is frequently required in patients with aneurysmal subarachnoid hemorrhage who develop subsequent hydrocephalus. Procedures such as external ventricular drain (EVD) and ventriculoperitoneal shunt (VPS) usually carry a very low rate of complications. However, as flow diverting stents such as Pipeline Embolization Device (PED) become more widely available, flow diverters are being used in treatment of some ruptured complex aneurysms. EVD and VPS placement in the setting of dual antiplatelet therapy (DAT) in these patients are associated with a significant risk of intracranial hemorrhage. We describe a management strategy and surgical technique that can minimize hemorrhagic complications associated with VPS in patients on DAT after treatment with flow diverting stents.

  3. The effect of arteriovenous fistulas on in situ saphenous vein bypasses

    DEFF Research Database (Denmark)

    Rørdam, Peter; Jensen, Leif Panduro; Schroeder, T;

    1991-01-01

    Intraoperative identification and later development of arteriovenous fistulas were investigated prospectively in 70 in situ saphenous vein bypass procedures. Surveillance was performed by completion arteriography and intra- and postoperative continuous wave Doppler examination. The intraoperative...

  4. Shunt insufficiency due to knot formation in the peritoneal catheter.

    Science.gov (United States)

    Fekete, Gábor; Nagy, Andrea; Pataki, István; Bognar, László; Novák, László

    2013-07-30

    The authors report a rare case of the peripheral obstruction of a ventriculoperitoneal shunt. Premature baby was operated on hydrocephalus due to germinal matrix bleeding. After two months of implantation of venticuloperitoneal shunt peripheral insufficiency of the system was emerged. During the shunt revision extensive knot formation became visible. We simply cut the catheter above the knot and the working shunt was replaced into the abdominal cavity. The postoperative course was uneventful and the baby was free of complaints for more than one year. The pathomechanism of knot formation is not clear thus the discovery of the problem during the operation is an unexpected event. In our opinion tight knot cannot be spontaneously formed intraabdominally. Loose knots can be developed and can reduce the capacity of liquor flow. We think that the knot tightens during pulling out. Longer peritoneal catheters can precipitate multiple looping and/or axial torquations and increase the peripheral resistance of the shunt. In such cases when the pulling out is challenged conversion to laparotomy is suggested.

  5. Laparoscopy for ventriculoperitoneal shunt implantation and revision surgery

    Institute of Scientific and Technical Information of China (English)

    Fernando; Campos; Gomes; Pinto; Matheus; Fernandes; de; Oliveira

    2014-01-01

    Ventriculoperitoneal shunting(VPS) is a widely accepted technique for the treatment of hydrocephalus. The probability of shunt dysfunction is pretty high throughout life. Laparoscopy has become a valuable tool to perform VPS and treat abdominal complications. An electronic literature search was performed to reveal the published data relating laparoscopy and ventriculoperitoneal shunt in Medline, Embase, Scielo and Lilacs databases. The keywords employed were “laparoscopy” OR “laparoscopic surgery” AND “ventriculoperitoneal shunt” OR “shunt” AND “surgery” OR “implantation” OR “revision” OR “complication”. No high quality trials were developed comparing conventional laparotomic incision vs laparoscopic approach. Both approaches have evolved and currently there are less invasive options for laparotomy, like periumbilical small incisions; and for laparoscopy, like smaller and less incisions. Operating room time, blood loss and hospital stay may be potentially smaller in laparoscopic surgery and complications are probably the same as laparotomy. In revision surgery for abdominal complications after VPS,visualization of whole abdominal cavity is fundamental to address properly the problem and laparoscopic approach is valuable once it is safe, fast and much less invasive than laparotomy. Ventriculoperitoneal shunting is a widely accepted technique for the treatment of hydrocephalus. Laparoscopy assisted shunt surgery in selected cases might be a less invasive and more effective option for intrabdominal manipulation. The laparoscopic approach allows a better catheter positioning, lysis of fibrotic bundles and peritoneal inspection as well, without any additional complication.

  6. Model of Shunting Technology Based on System Structure

    Directory of Open Access Journals (Sweden)

    Anton Pepevnik

    2003-09-01

    Full Text Available Railway transport is facing a growing liquidity problem.The major problem in small systems is the detention of wagonsat marshalling yards, which prolongs the time of freight travel.To avoid this problem it is of great importance to search for parametersthat would enable creation of a model of technologythat would provide shorter wagon detention time at stations aswell as optimising the number of marshalling yards for smallsystems. It is at the same time a great opportunity to search for alink between the shunting work in the railway transport and thetheoretical system approach which presents it as a current scientificproblem. In classical technology the shunting work iscarried out with no application of and no regard for the systemapproach. With new shunting systems in the railway transportthe regard for theory of transport systems is crucial as the secondarylevel of classical methods.As already pointed out, from the theoretical point of viewan important contribution will be made to the use of system theoryfor shunting purposes, since the suggested model effectivelyprovides the approach of analysing separate elements in therailway transport structure into integral shunting operations atthe railway stations.

  7. Spinal dural arteriovenous fistula: Imaging features and its mimics

    Energy Technology Data Exchange (ETDEWEB)

    Jeog, Ying; Ting, David Yen; Hsu, Hui Ling; Huang, Yen Lin; Chen, Chi Jen; Tseng, Ting Chi [Dept. of Radiology, aipei Medical University-Shuang Ho Hospital, New Taipei City, Taiwan (China)

    2015-10-15

    Spinal dural arteriovenous fistula (SDAVF) is the most common spinal vascular malformation, however it is still rare and underdiagnosed. Magnetic resonance imaging findings such as spinal cord edema and dilated and tortuous perimedullary veins play a pivotal role in the confirmation of the diagnosis. However, spinal angiography remains the gold standard in the diagnosis of SDAVF. Classic angiographic findings of SDAVF are early filling of radicular veins, delayed venous return, and an extensive network of dilated perimedullary venous plexus. A series of angiograms of SDAVF at different locations along the spinal column, and mimics of serpentine perimedullary venous plexus on MR images, are demonstrated. Thorough knowledge of SDAVF aids correct diagnosis and prevents irreversible complications.

  8. Jugular-axillary vein bypass for salvage of arteriovenous access.

    Science.gov (United States)

    Fulks, K D; Hyde, G L

    1989-01-01

    Stenosis or occlusion of the subclavian vein can cause incapacitating upper extremity swelling and venous hypertension in the patient with an arteriovenous (AV) access. A case of subclavian vein occlusion is reported that was treated with internal jugular-axillary vein bypass. This procedure resulted in salvage of the access and rapid resolution of the associated upper extremity swelling. It was concluded that jugular-axillary vein bypass should be considered in patients who have massive upper extremity edema resulting from a functioning AV access and ipsilateral subclavian vein occlusion. Patients undergoing creation of an AV access who have had previous temporary subclavian catheters or previous early failure of an AV access should have phlebography before surgery.

  9. Arteriovenous fistulas aggravate the hemodynamic effect of vein bypass stenoses

    DEFF Research Database (Denmark)

    Nielsen, T G; Djurhuus, C; Pedersen, Erik Morre;

    1996-01-01

    PURPOSE: The purpose of this study was to assess the impact of arteriovenous fistulas combined with varying degrees of stenosis on distal bypass hemodynamics and Doppler spectral parameters. METHODS: In an in vitro flow model bypass stenoses causing 30%, 55%, and 70% diameter reduction were induced...... 10 cm upstream of a fistula with low outflow resistance. Flow and intraluminal pressure were measured proximal to the stenosis and downstream of the fistula. The waveform parameters peak systolic velocity, end-diastolic velocity, pulsatility index, and pulse rise time were determined from midstream...... Doppler spectra obtained 10 cm downstream of the fistula. All measurements were carried out with open and clamped fistula. RESULTS: At 30% diameter reducing stenosis opening of the fistula induced a 12% systolic pressure drop across the stenosis but had no adverse effect on the Doppler waveform parameters...

  10. Acute paraplegia following embolization of spinal dural arteriovenous fistula

    Institute of Scientific and Technical Information of China (English)

    HUANG Cheng-guang; QI Xiang-qian; CHEN Huai-rui; L(U) Li-quan; WU Xiao-jun; BAI Ru-lin; LU Yi-cheng

    2011-01-01

    Embolization therapy has been used as the initial treatment for spinal dural arteriovenous fistula (SDAVF) only for certain patients or in certain medical institutions due to its minimal invasiveness, but the recurrence of embolization remains a clinical challenge. The recurrent patient usually exhibits a gradual onset of symptoms and progressive deterioration of neurological function. Developing paraplegia several hours after embolization is commonly seen in patients with venous thrombosis-related complications, for which anticoagulation therapy is often administered. This article reports on a SDAVF patient who had weakness of both lower extremities before embolization and developed complete paraplegia several hours after embolization therapy, later confirmed by angiography as fistula recurrence. The symptoms were relieved gradually after second embolization. The pathophysiology of this patient is also discussed.

  11. Intracranial dural arteriovenous fistula with spinal medullary venous drainage

    Energy Technology Data Exchange (ETDEWEB)

    Wiesmann, M.; Padovan, C.S.; Pfister, H.W.; Yousry, T.A. [Muenchen Univ. (Germany). Abt. fuer Neuroradiologie

    2000-10-01

    We report on a 46-year-old patient in whom an intracranial dural arteriovenous (AV) fistula, supplied by a branch of the ascending pharyngeal artery, drained into spinal veins and produced rapidly progressive symptoms of myelopathy and brainstem dysfunction including respiratory insufficiency. Magnetic resonance imaging studies demonstrated brainstem oedema and dilated veins of the brainstem and spinal cord. Endovascular embolization of the fistula led to good neurological recovery, although the patient had been paraplegic for 24 h prior to embolization. This case demonstrates the MRI characteristics of an intracranial dural AV fistula with spinal drainage and illustrates the importance of early diagnosis and treatment. Even paraplegia may be reversible, if angiography is performed and the fistula treated before ischaemic and gliotic changes become irreversible. (orig.)

  12. Spontaneous Regression of Uterine Arteriovenous Malformations with Conservative Management

    Science.gov (United States)

    Oishi, Sugiko; Akamine, Kozue; Heshiki, Chiaki

    2017-01-01

    Uterine arteriovenous malformation (AVM) can cause massive hemorrhage and is often treated with uterine artery embolization (UAE), which may lead to ovarian insufficiency. Thus, avoiding UAE should be considered, particularly in women undergoing fertility treatments. We present three women diagnosed with postmiscarriage AVM on color Doppler by transvaginal ultrasound imaging. They had no genital bleeding and a small mass, measuring 16–22 mm. If estradiol was >300 pg/mL when AVM was diagnosed, then a gonadotropin-releasing hormone agonist was administered. All three women underwent follow-up observation, revealing spontaneous mass disappearance. To avoid ovarian insufficiency risk with UAE, conservative management and close follow-up observation should be considered in patients with AVM without bleeding, particularly during the fertility treatment. PMID:28299220

  13. Renal aneurysm and arteriovenous fistula; Management with transcatheter embolization

    Energy Technology Data Exchange (ETDEWEB)

    Savastano, S.; Feltrin, G.P.; Miotto, D.; Chiesura-Corona, M. (Padua Univ. (Italy). Ist. di Radiologia Padua Univ. (Italy). Ist. di Fisioterapia)

    1990-01-01

    Embolization was performed in six patients with renal artery aneurysms (n=2) and arteriovenous fistulas (AVF) (n=5). The aneurysms were observed in one patient with fibromuscular dysplasia and in another with Ehlers-Danlos syndrome. All the AVFs were intraparenchymal and secondary to iatrogenic trauma. Elective embolization was performed in five patients with good clinical results at follow-up between 1 and 9 years. Because of rupture of the aneurysm emergency embolization was attempted without success in the patient with Ehlers-Danlos syndrome, and nephrectomy was carried out. A postembolization syndrome complicated three procedures in which Gelfoam and polyvinyl alcohol were used; in two of these cases unexpected reflux of the particulate material occurred, resulting in limited undesired ablation of the ipsilateral renal parenchyma. Embolization is the most reliable and effective treatment for intrarenal vascular abnormalities since it minimizes the parenchymal damage. (orig.).

  14. Experimental model of arteriovenous malformation in vitro using biological grafts

    Directory of Open Access Journals (Sweden)

    Sandu Aurelia Mihaela

    2015-06-01

    Full Text Available Introduction: Brain arteriovenous malformations (AVMs represent a serious health problem all around the world. Experimental models help to better understand the pathophysiology of these lesions. Experiment: We performed an experimental model of AVM using biological grafts, arteries and veins harvested from chicken wings at the elbow joint. We used 14 vessels and we performed 20 end-to-end anastomoses to create a nidus with a single feeding artery and a single draining vein. The system was irrigated with colored solution. The experiment was done according with law in force regarding experimental research activity. Conclusions: Experimental models allow us to understand the hemodynamics and predict the outcome of brain AVMs in humans. This experimental model is a useful tool in understanding the hemodynamic properties of brain AVMs. It is very useful in vascular anastomosis training

  15. Kernohan's phenomenon associated with left ruptured occipital arteriovenous malformation.

    Science.gov (United States)

    Fujimoto, A; Sato, H; Katayama, W; Nakai, K; Tsunoda, T; Kobayashi, E; Nose, T

    2004-05-01

    A 23-year-old woman presented with ipsilateral hemiparesia due to rupture of a left occipital arteriovenous malformation (AVM). Emergency decompression (the onset-operation interval was 46 minutes,) was carried out and the patient could leave the hospital upon recovery without neurological deficits. In general, Kernohan's phenomenon is caused by the gradual displacement of the cerebral peduncle against the tentorial edge caused by compression by the contralateral mass. This phenomenon is very rare among the cases with spontaneous intracranial hemorrhage and only three cases including the present one have been reported in the literature. In all cases the onset-operation intervals of were very short. Kernohan's phenomenon associated with a ruptured AVM is a rare condition and emergency decompression is required.

  16. Traumatic arteriovenous fistula due to an old gunshot injury: a victim from the Afghanistan War.

    Science.gov (United States)

    Dabbagh, Ali; Mar'ashi, Ali S; Malek, Bahman

    2007-10-01

    A 75-year-old man referred to the outpatient vascular surgery clinic of Taleghani Hospital (Shaheed Beheshti University of Medicine, Tehran, Iran) due to a local nontender mass in his groin. In his history, it was discovered that the mass had appeared a few months after a gunshot injury. He had a history of shortness of breath with a New York Heart Association functional class fluctuating between II and III, but no history of smoking or addiction. In the physical examination, a 5-cm by 5-cm nonpulsatile mass with engorged vessels was found in the anterior portion of the left groin, which was not tender. An elective arterial angiography revealed an arteriovenous fistula joining the femoral artery to the femoral vein at the left groin. The cardiac assessments revealed cor pulmonale (with a restrictive pattern and diastolic dysfunction) and pulmonary hypertension due to primary pulmonary dysfunction. The patient was anesthetized with a balanced general anesthesia method, considering all relevant cardiac and respiratory monitoring methods and specially withholding drugs increasing pulmonary vascular bed pressure, suppressing the myocardium, or increasing the regurgitant flow across the mitral and, especially, the tricuspid valve. The moment the fistula was closed, a rapid fall in the patient's heart rate was noted, from approximately 60 beats per minute to above 40 beats per minute; this decreased heart rate continued up to a few hours after the surgery and did not accompany any significant hemodynamic derangement including the patient's blood pressure. The patient received his postoperative care in the ordinary surgical ward and was discharged a few days later.

  17. Transcatheter coil embolisation of pulmonary arteriovenous malformations; Transkatheterembolisation pulmonaler arterio-venoeser Fisteln

    Energy Technology Data Exchange (ETDEWEB)

    Wingen, M.; Guenther, R.W. [Technische Hochschule Aachen (Germany). Klinik fuer Radiologische Diagnostik

    2001-07-01

    Evaluation of technical success, complications and long-term results of transcatheter coil embolisation in pulmonary arteriovenous malformations (pAVMs). Material and Methods: Transcatheter embolisations of 46 pAVMs in 14 patients were analysed retrospectively, and, 5 years after treatment, the patients were interviewed by telefone concerning persistent symptoms and complications. Main symptoms before embolisation were dyspnoe (86%), hypoxaemia (100%), cerebral ischemia (21%), and hemoptysis (14%); 11 patients (79%) suffered from hereditary hemorrhagic telangiectasia. Results: Embolisation with an average of 3,9 coils (min. 1, max. 19 coils) per pAVM yielded technical success in all cases. Only two minor complications, transitory pleuritis and a small lung infarction were observed. On follow up examination after 5 years either no residual complaints or substantial improvement of dyspnoe were reported; no patient suffered from neurologic or hemorrhagic complications after the embolisation. Conclusion: Transcatheter embolisation is a safe and minimally invasive therapy for pAVMs and has rightfully replaced surgical resection as the therapy of choice. (orig.) [German] Bewertung der Spiralembolisation pulmonaler AV-Fisteln hinsichtlich Erfolgsrate, Komplikationen und Langzeitergebnissen. Material und Methoden: Retrospektiv wurden die Transkatheterembolisationen von 46 pulmonalen AV-Fisteln bei 14 Patienten ausgewertet und die Patienten bzw. ihre Hausaerzte im Mittel 5 Jahre nach der Intervention telefonisch nachbefragt. Fuehrende Symptome vor der Behandlung waren Belastungsdyspnoe (86%), Hypoxaemie (100%), zerebrale Ischaemien (21%) und Haemoptysen (14%); 11 der Patienten (79%) litten an M. Osler. Ergebnisse: die Embolisation mit im Mittel 3,9 Spiralen (minimal 1, maximal 19 Spiralen) pro Fistel war in allen Faellen technisch erfolgreich, Komplikationen waren mit einer leichten Pleuritis und einer Infarktpneumonie selten und nicht gravierend. Alle nachbefragten

  18. Ethanol embolization of arteriovenous malformations: results and complications of 33 cases

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Yong Hwan; Do, Young Soo; Shin, Sung Wook; Liu, Wei Chiang; Cho, Jae Min; Lee, Min Hee; Kim, Dong Ik; Lee, Byung Boong; Choo, Sung Wook; Choo, In Wook [School of Medicine, Sungkyunkwan Univ., Seoul (Korea, Republic of)

    2003-10-01

    To assess the effectiveness of ethanol embolization for the treatment of arteriovenous malformation (AVM), and the complications, if any, arising. Thirty-three patients with AVMs underwent 145 staged sessions of ethanol embolization. AVMs were located in an upper extremity (n=14), a lower extremity (n=10), the pelvis (n=7), the thorax (n=1), or the abdomen (n=1). Eighty-five transcatheter embolizations and 60 direct percutaneous puncture embolizations were performed, and seven patients underwent additional coil embolization of the dilated outflow vein. The therapeutic effectiveness of embolization was evaluated in terms of the extent to which an AVM was obliterated between baseline and the final angiogram. Complications were classified as minor or major. In 13 patients (39%), AVMs were totally obliterated. In eight patients (24%), more than 75% were obliterated; in three (9%), the proportion was 50-75%; and in four (12%), less than 50%. Five patients (15%), were not treated. The reasons for failure were the difficulty of approaching the nidus due to previous surgical ligation or coil embolization of the feeding artery, the subcutaneous location of an AVM, post-procedural infection, and massive bleeding during the follow-up period. Twenty-one minor complications such as focal skin necrosis or transient nerve palsy developed during 145 sessions of (an incidence of 14%), but these were relieved by conservative treatment. The five major complications arising (3%) were cerebral infarction, urinary tract infection, acute renal failure due to rhabdomyolysis, permanent median nerve palsy, and infection. Ethanol embolization by direct percutaneous puncture or using a transcatheter technique is an effective approach to the treatment of an AVM. However, to overcome the considerable number of complications, arising, further investigation is required.

  19. Fístula arterio-venosa secundaria a picadura de raya de río Arteriovenous fistula secondary to stingray puncture

    Directory of Open Access Journals (Sweden)

    Rodrigo Girón

    1993-03-01

    Full Text Available

    Se presenta el caso de un paciente de sexo masculino, pescador, lesionado en la región fe. moral por una raya de río (Potamotrygon magdalenne lo que le produjo una fístula arterio-venosa de los vasos femorales. Fue tratado exitosamente mediante rafia de la vena y resección y anastomosis término-terminal de la arteria. En una revisión del tema no se encontraron informes previos de fístulas A-V de esta etiología.

    We report on the case of a fisherman who was wounded by a stingray (Potamotrygon magdalenne. As a consequence he developed a femoral arterio-venous fistula that was surgical treated with success. Suture of the vein and end to end anastomosis of the artery were performed. A review of the literature yielded no cases of arteriovenous fistula of this etiology.

  20. [Usefulness of IPC continuous monitoring in shunt dysfunction].

    Science.gov (United States)

    Horcajadas, A; Román, A; Olivares, G; Saura, E; Jorques, A; Cordero, N; Ibáñez, B; Sánchez, C; Roldán, M A

    2011-08-01

    Shunt dysfunction is a common situation in neurosurgery. Often symptoms, physical examination and radiology are not enough to set a diagnosis. ICP continuous monitoring is a safe and reliable tool that provides valuable information about CSF dynamics in these patients. Not only quantitative analysis is needed but also a qualitative one that enables pathological waves identification, because high amplitude B waves are strongly related to shunt dysfunction. In this paper experience about ICP continuous monitoring in patients with shunt dysfunction suspect is presented. Quantitative and qualitative data analysis led to a correct diagnosis, improving all the patients treated according to this criterion. An intraparenchymatous Camino® sensor and neuroPICture software (developed by first author) for data collection and graphic representation were used. Complications related to monitoring were absent and graphics obtained useful for qualitative analysis.

  1. The Behaviour of Mistuned Piezoelectric Shunt Systems and Its Estimation

    Directory of Open Access Journals (Sweden)

    M. Berardengo

    2016-01-01

    Full Text Available This paper addresses monoharmonic vibration attenuation using piezoelectric transducers shunted with electric impedances consisting of a resistance and an inductance in series. This type of vibration attenuation has several advantages but suffers from problems related to possible mistuning. In fact, when either the mechanical system to be controlled or the shunt electric impedance undergoes a change in their dynamical features, the attenuation performance decreases significantly. This paper describes the influence of biases in the electric impedance parameters on the attenuation provided by the shunt and proposes an approximated model for a rapid prediction of the vibration damping performance in mistuned situations. The analytical and numerical results achieved within the paper are validated using experimental tests on two different test structures.

  2. Cerebrospinal fluid galactorrhea: a rare complication of ventriculoperitoneal shunting.

    Science.gov (United States)

    Lee, Sai-Cheung; Chen, Jyi-Feng; Tu, Po-Hsun; Lee, Shih-Tseng

    2008-06-01

    In this report we describe a 26-year-old woman who had an intra-abdominal pseudocyst located at the peritoneal catheter tip following ventriculo-peritoneal (VP) shunt implantation. Retrograde cerebrospinal fluid (CSF) flowed outside the catheter and communicated with the right breast lactiferous ductal system and leaked from the nipple orifice. CSF galactorrhea only occurs when the lactiferous duct is injured during VP shunt implantation, in combination with the formation of an intra-abdominal CSF pseudocyst prior to lactiferous duct healing. Leakage of CSF from the nipple orifice can be successfully treated by simply guiding the peritoneal catheter tip into the peritoneal cavity through a new laparotomy; that is, shunt revision is not always required.

  3. Percutaneous gastrostomy tube placement in patients with ventriculoperitoneal shunts

    Energy Technology Data Exchange (ETDEWEB)

    Sane, S.S.; Towbin, A.; Bergey, E.A.; Kaye, R.D.; Fitz, C.R.; Albright, L.; Towbin, R.B. [Department of Radiology, Children`s Hospital of Pittsburgh, 3705 Fifth Avenue, Pittsburgh, PA 15213 (United States)

    1998-07-01

    Objective. The purpose of this study is to determine the risk of CNS and/or peritoneal infection in children with ventriculoperitoneal shunts in whom a percutaneous gastrostomy tube is placed. Materials and methods. We placed 205 gastrostomy or gastrojejunostomy tubes from January of 1991 to December 1996. Twenty-three patients (10 boys, 13 girls) had ventriculoperitoneal shunts at the time of placement. All shunts were placed at least 1 month prior to placement of the gastrostomy tube. The patients ranged in age from 8 months to 16 years with a mean age of 6 years, 9 months. Patient weight ranged from 2 kg to 60 kg. All 23 children required long-term nutritional support due to severe neurologic impairment. No prophylactic antibiotics were given prior to the procedure. Of the patients, 21/23 had a 14-F Sacks-Vine gastrostomy tube with a fixed terminal retention device inserted, using percutaneous fluoroscopic antegrade technique. Two of the 23 patients had a Ross 14-F Flexi-flo gastrostomy tube which required a retrograde technique due to a small caliber esophagus in these children. Results. All 23 children had technically successful placements of percutaneous gastrostomy (7) or gastrojejunostomy (16) tubes. Of the children, 21/23 (91 %) had no complications from the procedure. Two of 23 (9 %) patients demonstrated signs of peritonitis after placement of their gastrostomy tubes and subsequently had shunt infections. In both, children CSF culture grew gram-positive cocci. The antegrade technique was used in both children who developed peritonitis. Conclusion. Our study indicates children with ventriculoperitoneal shunts who undergo percutaneous gastrostomy are at greater risk for infection and subsequent shunt malfunction. Therefore, we recommend prophylactic antibiotic therapy to cover for skin and oral flora. (orig.) With 1 fig., 7 refs.

  4. Portacaval shunt established in six dogs using magnetic compression technique.

    Directory of Open Access Journals (Sweden)

    Xiaopeng Yan

    Full Text Available BACKGROUND AND AIMS: Installing the transjugular intrahepatic portosystemic shunt for portal hypertension is relatively safe, but complications are still high. To explore a new method of portacaval shunt, the magnetic compression technique was introduced into the shunting procedure. METHODS: A portal-inferior vena cava shunt was performed on 6 male mongrel dogs by two hemocompatible Nd-Fe-B permanent magnets, parent and daughter. The parent magnet was applied to the inferior vena cava guided by a catheter through the femoral vein. The daughter magnet was moved to the anastomosis position on the portal vein with a balloon catheter through the splenic vein. After the daughter magnet reached the target position, the two magnets acted to compress the vessel wall and hold it in place. Five to 7 days later, under X-ray guidance, the magnets were detached from the vessel wall with a rosch-uchida transjugular liver access set. One month later, histological analysis and portal venography were performed. RESULTS: 5-7 days after the first surgery, a mild intimal hyperplasia in the portal vein and the inferior vena cava, and continuity of the vascular adventitia from the portal vein to the inferior vena cava as observed. During the second surgery, the contrast media could be observed flowing from the portal vein into the inferior vena cava. Portal venography revealed that the portosystemic shunt was still present one month after the second surgery. CONCLUSIONS: Magnamosis via a device of novel design was successfully used to establish a portacaval shunt in dogs.

  5. Shunted Piezoelectric Vibration Damping Analysis Including Centrifugal Loading Effects

    Science.gov (United States)

    Min, James B.; Duffy, Kirsten P.; Provenza, Andrew J.

    2011-01-01

    Excessive vibration of turbomachinery blades causes high cycle fatigue problems which require damping treatments to mitigate vibration levels. One method is the use of piezoelectric materials as passive or active dampers. Based on the technical challenges and requirements learned from previous turbomachinery rotor blades research, an effort has been made to investigate the effectiveness of a shunted piezoelectric for the turbomachinery rotor blades vibration control, specifically for a condition with centrifugal rotation. While ample research has been performed on the use of a piezoelectric material with electric circuits to attempt to control the structural vibration damping, very little study has been done regarding rotational effects. The present study attempts to fill this void. Specifically, the objectives of this study are: (a) to create and analyze finite element models for harmonic forced response vibration analysis coupled with shunted piezoelectric circuits for engine blade operational conditions, (b) to validate the experimental test approaches with numerical results and vice versa, and (c) to establish a numerical modeling capability for vibration control using shunted piezoelectric circuits under rotation. Study has focused on a resonant damping control using shunted piezoelectric patches on plate specimens. Tests and analyses were performed for both non-spinning and spinning conditions. The finite element (FE) shunted piezoelectric circuit damping simulations were performed using the ANSYS Multiphysics code for the resistive and inductive circuit piezoelectric simulations of both conditions. The FE results showed a good correlation with experimental test results. Tests and analyses of shunted piezoelectric damping control, demonstrating with plate specimens, show a great potential to reduce blade vibrations under centrifugal loading.

  6. Ventriculoperitoneal shunt complications in hydrocephalus patients with intracranial tumors: an analysis of relevant risk factors.

    Science.gov (United States)

    Reddy, G Kesava; Bollam, Papireddy; Caldito, Gloria; Willis, Brian; Guthikonda, Bharat; Nanda, Anil

    2011-06-01

    Patients with intracranial tumors are predisposed to persistent hydrocephalus, often requiring a permanent CSF diversion procedure with shunts. This study reviews the long-term experience with ventriculoperitoneal shunts for the management of hydrocephalus in patients with intracranial tumors. Patients with intracranial tumors who underwent ventriculoperitoneal shunt placement for hydrocephalus from October 1990 to October 2009 were included in this study. During the 19-year period, medical charts, operative reports, imaging studies, and clinical follow- up evaluations were reviewed and analyzed retrospectively for all patients. A total of 187 intracranial tumor patients with hydrocephalus were included. The median follow up was 391 days. Malignant tumors were present in 40% of the patients. Overall shunt failure was 27.8%. Single shunt revision occurred in 13% of the patients and 14% had multiple shunt revision. Tumor histology, age and a procedure prior to shunt placement (ventriculostomy/Ommaya reservoirs) were significantly associated with the shunt revisions. Shunt system replacement and proximal shunt complication were significantly attributed to multiple shunt revisions. The overall shunt revision within 3 months, 6 months, 1 year and 5 years was 17.7%, 18.7%, 19.8% and 24.1%, respectively. The results of the study demonstrate that VP shunting is an effective for the management of hydrocephalus in patients with intracranial tumors. The overall incidence of shunt revision was 27.8%. Age, tumor histology, and a procedure prior to shunt placement (ventriculostomy/Ommaya reservoirs) were significantly associated with the shunt revisions. Additional studies using minimally invasive techniques are being explored for the management of hydrocephalus in patients with intracranial tumors.

  7. Rectal extrusion of the catheter and air ventriculography following bowel perforation in ventriculo-peritoneal shunt

    Energy Technology Data Exchange (ETDEWEB)

    Arico, M.; Podesta, A.F.; Bianchi, E.; Beluffi, G.; Fiori, P.; Chiari, G.; Pezzotta, S.

    1985-01-01

    Ventriculo-peritoneal shunt is frequently carried out in infantile hydrocephalus. The peritoneal shunt has a lower morbidity than ventriculo-atrial shunt and severe complications are uncommon. Abdominal complications include intestinal perforation, shunt migration, inguinal hernia, cerebrospinal fluid pseudocysts and hollow viscus perforation. A few cases of catheter extrusion from the rectum, vagina, umbilicus and urethra have been described. We report a new case of intestinal perforation with rectal extrusion of the catheter associated with a ventriculogram.

  8. Measurement of shunt amount using radionuclide angiocardiography: accuracy according to level of shunt and associated lesion

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yang Min [Sejong General Hospital, Bucheon (Korea, Republic of)

    2006-08-15

    Determination of pulmonary to systemic blood flow ratio (QP/QS) is important for the management of patients with left-to-right shunt. This study was performed to assess the agreement of Qp/Qs ratio using the radionuclide method and oxymetry, to investigate the factors influencing the agreement, and to know how interchangeable the results of each technique. We compared the Qp/Qs measured by single-pass radionuclide angiocardiography and oxymetry during catheterization in 207 patients who underwent both studies. In radionuclide method, Qp/Qs was calculated from the pulmonary time-activity curves using a gamma variate fit. The correlation and Bland-Altman analysis were performed according to the levels of shunt and associated lesions. The mean Qp/Qs was 1.83 {+-} 0.50 by radionuclide, and 1.74 {+-} 0.51 by oxymetry. The overall correlation coefficient was 0.86 ({rho} 0.001), and Bland-Altman range of agreement encompassing 4SD was 1.05. For atrial septal defect, ventricular septal defect, patent ductus arteriosus, tricuspid and mitral insufficiency, the correlation coefficient was 0.78, 0.90, 0.84, 0.63 and 0.44 and Bland-Altman range was 1.52, 0.74, 0.96, 1.57 and 1.50, respectively. There is good agreement but wide variance between the Qp/Qs ratios by radionuclide method and oxymetry. Associated atrioventricular valvar insufficiency decreases the correlation coefficient and widens the variance. Wide overall variance suggests that Qp/Qs measurements by two techniques should not be used interchangeably.

  9. Dynamic actuation methods for capacitive MEMS shunt switches

    Science.gov (United States)

    Khater, M. E.; Vummidi, K.; Abdel-Rahman, E. M.; Nayfeh, A. H.; Raman, S.

    2011-03-01

    We develop dynamic actuation methods for capacitive MEMS shunt switches. We show that the dynamic actuation voltage is significantly less than the static actuation voltage and demonstrate 60% reduction in the actuation voltage. We also show that this reduction in the actuation voltage depends on the specific dynamic switching technique adopted. For a given operating condition, the minimum realizable switching time is that obtained using static switching. However, we developed a dynamic switching method that yields comparable switching time to that minimum. We also found that squeeze-film damping is the dominant damping mechanism for a shunt switch with a relatively slender bridge (aspect ratio of 11:1).

  10. Balanced calibration of resonant shunt circuits for piezoelectric vibration control

    DEFF Research Database (Denmark)

    Høgsberg, Jan; Krenk, Steen

    2012-01-01

    Shunting of piezoelectric transducers and suitable electric circuits constitutes an effective passive approach to resonant vibration damping of structures. Most common design concepts for resonant resistor-inductor (RL) shunt circuits rely on either maximization of the attainable modal damping...... series and parallel RL circuits. The procedure relies on equal modal damping and sufficient separation of the complex poles to avoid constructive interference of the two modes. By comparison with existing design procedures, it is demonstrated that the present calibration leads to a balanced compromise...

  11. Cryptococcal cerebrospinal fluid shunt infection treated with fluconazole

    Directory of Open Access Journals (Sweden)

    Daniel Eymard

    1993-01-01

    Full Text Available A 37-year-old woman with a cadaveric renal allotransplantation required intra-cranial shunting devices after a presumptive episode of tuberculous meningitis. Six months later, she developed a culture-proven cryptococcal meningitis. Without having her ventriculo-auricular shunt removed, she was successfully treated with a short course of amphotericin B (335 mg and flucytosine (nine days followed by prolonged therapy with oral fluconazole (400 mg daily for 72 days. Three years post treatment she had no evidence of relapse, and normal renal graft function.

  12. Shoulder tip pain: an under-reported complication of ventriculoperitoneal shunt.

    LENUS (Irish Health Repository)

    Lim, C

    2012-02-03

    Ventriculoperitoneal (VP) shunt insertion is the commonest form of treatment for hydrocephalus. Shoulder tip pain after VP shunt insertion is unusual and has only recently been reported. We present a case of excruciating shoulder tip pain due to diaphragmatic irritation after VP shunt insertion.

  13. Management for traumatic chronic subdural hematoma patients with well-controlled shunt system for hydrocephalus.

    Science.gov (United States)

    Yamada, Shoko Mitrrt; Tomia, Yusuke; Murakami, Hideki; Nakane, Makoto

    2015-07-01

    Traumatic CSDH enlarged in two cases with VP or LP shunt system although the shunt valve pressure was increased to 200 mmH2O. In surgery, the hematoma cavity pressure was found to be 130 and 140 mmH2O, suggesting that to raise the shunt valve pressure is not effective for decreasing CSDH volume.

  14. Ultrasonography of portosystemic shunting in dogs : Doppler studies before, during and after surgery

    NARCIS (Netherlands)

    Szatmári, V.

    2004-01-01

    Portosystemic shunting occurs when anomalous veins allow the portal blood to enter the systemic veins directly without first flowing through the hepatic sinusoids. Portosystemic shunting can occur via acquired portosystemic collaterals or via congenital portosystemic shunts and may result in clinica

  15. Perforation into gut by ventriculoperitoneal shunts: A report of two cases and review of the literature

    Directory of Open Access Journals (Sweden)

    Abdul Hai

    2011-01-01

    Full Text Available We report two cases of gastrointestinal perforation by ventriculoperitoneal (VP shunts and review the literature on the topic. The time interval between shunt surgery and detection of bowel perforation is minimum in infants and increases with age. Sigmoid and transverse colon followed by stomach are the most frequent sites of gastrointestinal perforations by VP shunts.

  16. Locally Resonant Gaps of Phononic Beams Induced by Periodic Arrays of Resonant Shunts

    Institute of Scientific and Technical Information of China (English)

    CHEN Sheng-Bing; WEN Ji-Hong; WANG Gang; HAN Xiao-Yun; WEN Xi-Sen

    2011-01-01

    @@ Periodic arrays of shunted piezoelectric patches are employed to control the propagation of elastic waves in phononic beams.Each piezo-patch is connected to a single resistance-inductance-capacitance shunting circuit.Therefore,the resonances of the shunting circuits will produce locally resonant gaps in the phononic beam.However,the existence of locally resonant gaps induced by resonant shunts has not been clearly proved by experiment so far.In this work,the locally resonant gap in a piezo-shunted phononic beam is investigated theoretically and verified by experiment.The results prove that resonances of shunting circuits can produce locally resonant gaps in phononic beams.%Periodic arrays of shunted piezoelectric patches are employed to control the propagation of elastic waves in phononic beams. Each piezo-patch is connected to a single resistance-inductance-capacitance shunting circuit. Therefore, the resonances of the shunting circuits will produce locally resonant gaps in the phononic beam. However, the existence of locally resonant gaps induced by resonant shunts has not been clearly proved by experiment so far. In this work, the locally resonant gap in a piezo-shunted phononic beam is investigated theoretically and verified by experiment. The results prove that resonances of shunting circuits can produce locally resonant gaps in phononic beams.

  17. TRANSIENT ARTHRITIS WITH POSITIVE TESTS FOR RHEUMATOID-FACTOR AS PRESENTING SIGN OF SHUNT NEPHRITIS

    NARCIS (Netherlands)

    TERBORG, EJ; VANRIJSWIJK, MH; KALLENBERG, CGM

    1991-01-01

    Shunt nephritis is a rare complication of a chronically infected ventriculoatrial shunt. A 17 year old boy is described, with arthritis in both ankles and positive rheumatoid factor tests, who presented with symptoms of shunt nephritis. Blood cultures were positive for Staphylococcus epidermidis. Th

  18. A 10-year experience with the Amatsu tracheoesophageal shunt Experiência de 10 anos com o shunt traqueoesofágico de Amatsu

    Directory of Open Access Journals (Sweden)

    Mauro Becker M. Vieira

    2002-10-01

    Full Text Available Introduction: Since 1991, we have done the tracheoesophageal shunt as described by Amatsu in candidates to a total laryngectomy. Our goal is to provide the patients a better speech rehabilitation that that obtained by the non-surgical techniques, and by doing so, lessen the oncological treatment impact on the patient's quality of life. Aim: This work revises the experience of our institution with the procedure during a 10 years period. Study design: Clinical retrospective. Material and method: We had 54 patients submitted to the procedure, 3 women e 51 men, with ages from 30 to 78 years old and a mean age of 59 years. All had scamous cell carcinoma, 10 from the piriform sinus, 2 from retrocricoide area, 6 from the supraglottis, 1 from the subglottis, 16 from the glottis and 19 were transglottic. According to the AJC staging system, 3 were stage II, 17 were stage III, 24 were stage IV and 10 were not staged. Previous radiotherapy as initial treatment had been done in 18 patients. During the laryngectomy, 33 patients had some type of neck dissection and in 15 of these patients the neck dissection was done bilaterally. A myocutaneous pectoralis major flap was needed in 5 cases and a deltopectoralis flap was used in one case. Postoperative radiotherapy was used in 20 patients. Local infections occurred in 36% of the cases, and all had a good outcome. One patient died in the early postoperative period. Results: Speech rehabilitation by the technique was successful in 70% of the cases. Aspiration occurred in 10 patients and, in 2 of these, the shunt had to be surgically closed. Conclusion: In conclusion, due to its low cost, good results with few complications, the Amatsu tracheoesophageal shunt continues in our service as the main technique for speech rehabilitation after laryngectomy.Introdução: Desde 1991, os autores têm realizado o shunt traqueoesofágico descrito por Amatsu em pacientes submetidos a laringectomia total. A técnica visa

  19. Diagnosis of complications in ventriculo-peritoneal and ventriculo-atrial shunts. Diagnostik von Komplikationen ventrikuloperitonealer und ventrikuloatrialer Shunts

    Energy Technology Data Exchange (ETDEWEB)

    Langen, H.J.; Alzen, G.; Avenarius, R. (Technische Hochschule Aachen (Germany). Klinik fuer Radiologische Diagnostik); Mayfrank, L. (Technische Hochschule Aachen (Germany). Klinik fuer Neurochirurgie); Thron, A. (Technische Hochschule Aachen (Germany). Neuroradiologie); Kotlarek, F. (Technische Hochschule Aachen (Germany). Kinderklinik)

    1992-07-01

    The value of imaging (cranial CT, cranial and abdominal sonography, plain film surveys) was examined retrospectively in 28 shunted children in whom 82 instances of suspected dysfunction arose. There were 23 obstructions, 12 dislocations, 1 disconnection, 6 infections, 3 overdrainages and 5 slit ventricle syndromes. Impaired absorption with ascites, a peritoneal liquor cyst and a seroma occurred in the peritoneal part of the shunt. Progressive dilatation of the ventricle system shown by CCT (89%) or ultrasound was the most sensitive sign of high-pressure hydrocephalus. Periventricular hypodensity and flattening of the gyri (15%) were found less often. An examination strategy in suspected shunt dysfunction is suggested on the basis of these findings. (orig.).

  20. High-Flow Arterio-Hepatic Venous Shunt in Hepatocellular Carcinoma: Use of Multi-Electrode Radiofrequency for Shunt Obliteration

    Energy Technology Data Exchange (ETDEWEB)

    Pua, Uei, E-mail: druei@yahoo.com [Tan Tock Seng Hospital, Department of Diagnostic Radiology (Singapore)

    2015-10-15

    Intra-tumoral arterio-hepatic venous shunting (AHVS) poses an impediment to transarterial chemoembolization of liver tumors. Not only does it present a potential hazard for systemic shunting and embolization, but also the altered flow dynamics may also result in poor delivery of drug/embolics to the target tumor bed. Current available techniques to overcome AVHS include arterial embolization (particles, coils, glue, etc.) or temporary venous occlusion using balloons. We hereby illustrate the use of radiofrequency ablation to obliterate a complex AHVS consisting of a varix-like venous aneurysm.

  1. Risk factors for shunt malfunction in pediatric hydrocephalus: a multicenter prospective cohort study.

    Science.gov (United States)

    Riva-Cambrin, Jay; Kestle, John R W; Holubkov, Richard; Butler, Jerry; Kulkarni, Abhaya V; Drake, James; Whitehead, William E; Wellons, John C; Shannon, Chevis N; Tamber, Mandeep S; Limbrick, David D; Rozzelle, Curtis; Browd, Samuel R; Simon, Tamara D

    2016-04-01

    OBJECT The rate of CSF shunt failure remains unacceptably high. The Hydrocephalus Clinical Research Network (HCRN) conducted a comprehensive prospective observational study of hydrocephalus management, the aim of which was to isolate specific risk factors for shunt failure. METHODS The study followed all first-time shunt insertions in children younger than 19 years at 6 HCRN centers. The HCRN Investigator Committee selected, a priori, 21 variables to be examined, including clinical, radiographic, and shunt design variables. Shunt failure was defined as shunt revision, subsequent endoscopic third ventriculostomy, or shunt infection. Important a priori-defined risk factors as well as those significant in univariate analyses were then tested for independence using multivariate Cox proportional hazard modeling. RESULTS A total of 1036 children underwent initial CSF shunt placement between April 2008 and December 2011. Of these, 344 patients experienced shunt failure, including 265 malfunctions and 79 infections. The mean and median length of follow-up for the entire cohort was 400 days and 264 days, respectively. The Cox model found that age younger than 6 months at first shunt placement (HR 1.6 [95% CI 1.1-2.1]), a cardiac comorbidity (HR 1.4 [95% CI 1.0-2.1]), and endoscopic placement (HR 1.9 [95% CI 1.2-2.9]) were independently associated with reduced shunt survival. The following had no independent associations with shunt survival: etiology, payer, center, valve design, valve programmability, the use of ultrasound or stereotactic guidance, and surgeon experience and volume. CONCLUSIONS This is the largest prospective study reported on children with CSF shunts for hydrocephalus. It confirms that a young age and the use of the endoscope are risk factors for first shunt failure and that valve type has no impact. A new risk factor-an existing cardiac comorbidity-was also associated with shunt failure.

  2. Complications and subsequent removal of retained shunt hardware after endoscopic third ventriculostomy: case series.

    Science.gov (United States)

    Pindrik, Jonathan; Jallo, George I; Ahn, Edward S

    2013-06-01

    This case series highlights multiple complications and subsequent removal of retained shunt hardware in pediatric patients after successful endoscopic third ventriculostomy (ETV). Removal or retention of existing shunt hardware following ETV represents an important dilemma. Prior studies have reported infections and organ perforation related to nonfunctioning shunts but none in the context of successful ETV. Data obtained in 3 children with hydrocephalus treated at the authors' institution were retrospectively reviewed after the patients experienced complications due to retained shunt hardware following ETV. Etiologies of hydrocephalus included tectal glioma and intraventricular hemorrhage. All 3 patients had a history of multiple shunt revisions and underwent urgent ETV in the setting of a shunt malfunction. In each case, the entire shunt system was left in situ, but it became the source of subsequent complications. Two of the 3 patients presented with the shunt infected by gram-negative bacilli 10 days and 4.5 months postoperatively, respectively. The remaining patient experienced wound dehiscence over the shunt valve 4.5 months after ETV. In all patients, the complications were managed successfully by removing the shunt hardware. None of the patients required repeat shunt insertion from the time of removal throughout the follow-up period (mean 24 months, range 9-36 months). During the study period, a total of 6 patients with indwelling shunt hardware underwent ETV with the expectation of being shunt independent. Among these 6 patients, 3 experienced no complications from the retained hardware whereas 3 patients (50%) ultimately experienced adverse consequences related to retained hardware. This case series illustrates complications involving retained shunt hardware after successful ETV. These examples support consideration of shunt removal at the time of ETV in the appropriate context.

  3. Contemporary role of minimally invasive thoracic surgery in the management of pulmonary arteriovenous malformations: report of two cases and review of the literature

    Science.gov (United States)

    Wang, Stephani C.; Rosen, Jonathan M.

    2016-01-01

    Pulmonary arteriovenous malformations (PAVM) can have potentially serious neurological and cardiac consequences if left untreated. Embolization has supplanted surgical resection as the first line treatment modality. However, this technique is not always successful and carries risks of air embolism, migration of the coil, myocardial rupture, vascular injury, pulmonary hypertension, and pulmonary infarction. We present two patients with symptomatic PAVM despite multiple embolizations: the first one with recurrent and persistent hemoptysis who underwent a thoracoscopic lobectomy, and the second one with chronic debilitating pleuritic pain subsequent to embolization who underwent a thoracoscopic wedge resection. Video-assisted thoracoscopic surgery (VATS) with lung resection was successfully performed in both patients, with complete resolution of their symptoms. We also review the literature regarding the contemporary role of surgery in PAVM, particularly thoracoscopy. PMID:26904229

  4. Percutaneous transcatheter closure of a mitral paravalvular leak via anterograde approach without arteriovenous loop in a patient with double valve replacement

    Directory of Open Access Journals (Sweden)

    M. Boochi Babu

    2013-07-01

    Full Text Available Paravalvular leak (PVL is a rare but potentially serious complication of surgically implanted prosthetic heart valves. Patients who have PVL can be asymptomatic or present with haemolysis, heart failure, or endocarditis. The goldstandard treatment for prosthetic-valve PVL is surgery to repair or replace the valve but carries higher operative risk compared to the initial procedure. In view of this, percutaneous transcatheter closure of PVL is becoming an increasingly attractive alternative strategy. In this report, we describe a case of mitral PVL in a patient with double-valve replacement, which was successfully closed using Cocoon duct occluder device (Vascular Innovations Co., Ltd, Thailand via ante-grade approach, guided by transesophageal echocardiography (TEE and fluoroscopy and without complete arterio-venous loop.

  5. Contemporary role of minimally invasive thoracic surgery in the management of pulmonary arteriovenous malformations: report of two cases and review of the literature.

    Science.gov (United States)

    Bakhos, Charles T; Wang, Stephani C; Rosen, Jonathan M

    2016-01-01

    Pulmonary arteriovenous malformations (PAVM) can have potentially serious neurological and cardiac consequences if left untreated. Embolization has supplanted surgical resection as the first line treatment modality. However, this technique is not always successful and carries risks of air embolism, migration of the coil, myocardial rupture, vascular injury, pulmonary hypertension, and pulmonary infarction. We present two patients with symptomatic PAVM despite multiple embolizations: the first one with recurrent and persistent hemoptysis who underwent a thoracoscopic lobectomy, and the second one with chronic debilitating pleuritic pain subsequent to embolization who underwent a thoracoscopic wedge resection. Video-assisted thoracoscopic surgery (VATS) with lung resection was successfully performed in both patients, with complete resolution of their symptoms. We also review the literature regarding the contemporary role of surgery in PAVM, particularly thoracoscopy.

  6. Metabolic responses to moderate exercise in lambs with aortopulmonary shunts

    NARCIS (Netherlands)

    Beaufort-Krol, GCM; Takens, J; Zijlstra, WG; Molenkamp, MC; Gerding, AM; Kuipers, JRG

    2001-01-01

    In a previous study we found, after an overnight fast of 18 hours, a lower arterial glucose concentration and a depressed glycogenolysis in lambs with aortopulmonary left-to-right shunts. During exercise, glucose and free fatty acids (FFA) concentrations normally increase. The aim of this study was

  7. Wideband digital phase comparator for high current shunts

    CERN Document Server

    Pogliano, Umberto; Serazio, Danilo

    2011-01-01

    A wideband phase comparator for precise measurements of phase difference of high current shunts has been developed at INRIM. The two-input digital phase detector is realized with a precision wideband digitizer connected through a pair of symmetric active guarded transformers to the outputs of the shunts under comparison. Data are first acquired asynchronously, and then transferred from on-board memory to host memory. Because of the large amount of data collected the filtering process and the analysis algorithms are performed outside the acquisition routine. Most of the systematic errors can be compensated by a proper inversion procedure. The system is suitable for comparing shunts in a wide range of currents, from several hundred of milliampere up to 100 A, and frequencies ranging between 500 Hz and 100 kHz. Expanded uncertainty (k=2) less than 0.05 mrad, for frequency up to 100 kHz, is obtained in the measurement of the phase difference of a group of 10 A shunts, provided by some European NMIs, using a digit...

  8. Comparison of passive inductor designs for piezoelectric shunt damping

    Science.gov (United States)

    Lossouarn, Boris; Thierry, Olivier; Aucejo, Mathieu; Deü, Jean-François

    2016-04-01

    Considering piezoelectric damping, a resonant shunt can lead to a significant vibration reduction when tuned to the mechanical mode to control. However, limits appear when looking at practical applications in a low frequency range: the required inductance is often too high to be satisfied with standard passive components. Moreover, even if the inductor is eventually available, the internal resistance of the component generally exceeds the value which is required for a shunt optimization. Suitable inductors can be designed for applications requiring high inductance and low resistance values. Indeed, the permeance of a magnetic circuit can be significantly increased by the use of closed cores made of high permeability materials. In this paper, three designs are described and compared: an inductor from standard series and two handmade inductors involving a ferrite core and a nanocrystalline toroid. The components are successively integrated into a piezoelectric shunt dedicated to the vibration control of a cantilever beam. Depending on the frequency of the target mechanical mode to control, the benefits and the limits of the different inductors are observed. It is shown that custom designs can definitely extend to lower frequency the application of the passive resonant shunt strategy.

  9. Small-Diameter PTFE Portosystemic Shunts: Portocaval vs Mesocaval

    Directory of Open Access Journals (Sweden)

    Robert Shields

    1998-01-01

    Full Text Available Fifty-seven patients with failed sclerotherapy received a mesocaval interposition shunt with an externally supported, ringed polytetrafluoroethylene prosthesis of either 10 or 12 mm diameter. Thirty-one patients had Child-Pugh gradeA disease and 26 grade B; all had a liver volume of 1000– 2500 ml. Follow-up ranged from 16 months to 6 years 3 months. Three patients (5 per cent died in the postoperative period. There were two postoperative recurrences of variceal haemorrhage and one recurrent bleed in the second year after surgery. The cumulative shunt patency rate was 95 per cent and the incidence of encephalopathy 9 per cent; the latter was successfully managed by protein restriction and/or lactulose therapy. The actuarial survival rate for the whole group at 6 years was 78 per cent, for those with Child-Pugh grade A 88 per cent and for grade B 67 per cent. Small-lumen mesocaval interposition shunting achieves portal decompression, preserves hepatopetal flow, has a low incidence of shunt thrombosis, prevents recurrent variceal bleeding and is not associated with significant postoperative encephalopathy.

  10. Focally spared area of fatty liver caused by arterioportal shunt

    Energy Technology Data Exchange (ETDEWEB)

    Arita, Takeshi; Matsunaga, Naofumi [Yamaguchi Univ. School of Medicine (Japan); Honma, Yutaka [Shimonoseki City Hospital, Yamaguchi (Japan)] [and others

    1996-05-01

    We describe a case with a focally spared area in fatty liver caused by arterioportal shunt. Furthermore, we discuss the cause of the focally spared area related to a localized dilution or reduction in portal blood flow. 13 refs., 1 fig.

  11. Pericardial effusion and cardiac tamponade after ventriculoperitoneal shunt placement: a case report.

    Science.gov (United States)

    Wiwattanadittakul, Natrujee; Katanyuwong, Kamornwan; Jetjumnong, Chumpon; Sittiwangkul, Rekwan; Makonkawkeyoon, Krit

    2016-10-01

    Insertion of a ventriculoperitoneal shunt is a common neurosurgical procedure in both adult and paediatric patients. It is one of the most important treatments in cases of hydrocephalus; however, there is a wide range of complications: the most common complication being a shunt infection, and examples of rare complications are shunt migrations and cardiac tamponade. Several reports of distal ventriculoperitoneal shunt migration in different sites, including chest, right ventricle, pulmonary artery, bowel and scrotum were published. But pericardial effusion with cardiac tamponade and its relationship to distal ventriculoperitoneal shunt migration into the pericardial sac has never been reported.

  12. Pitfalls in the Performance and Interpretation of Scintigraphic Imaging for Pleuroperitoneal Shunt.

    Science.gov (United States)

    Covington, Matthew F; Choudhary, Gagandeep; Avery, Ryan J; Kuo, Phillip H

    2016-11-01

    Ascites can cause pleural effusions when the peritoneal fluid crosses the diaphragm through a pleuroperitoneal shunt in the setting of hepatic cirrhosis (hepatic hydrothorax) or malignant ascites. Scintigraphic imaging for pleuroperitoneal shunt requires intraperitoneal injection of Tc-SC or Tc-macroaggregated albumin followed by planar imaging of the chest and abdomen. Pleuroperitoneal shunt is confirmed by identifying radiotracer crossing the diaphragm from the peritoneal to pleural space. An atlas of pleuroperitoneal shunt imaging pitfalls is presented to facilitate optimal performance and interpretation of nuclear pleuroperitoneal shunt examinations. Examples include cases of nondiagnostic radiotracer injections, processing errors, and nontarget uptake.

  13. Efficacy of preoperative US vascular mapping for arteriovenous fistula in patients with hemodialysis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Min Sun; Hwang, Ji Young; Kang, Byung Chul; Baek, Seung Yon [College of Medicine, Ewha Womans University, Seoul (Korea, Republic of)

    2007-07-15

    The purpose of this study is to assess the efficacy of preoperative US vascular mapping to predict postoperative patency of the arteriovenous fistula for hemodialysis. Sixty-six patients who underwent hemodialysis for end-stage renal failure (M:F = 34:32, mean age, 58.8 years) were observed prospectively from January 2001 to April 2003. The patients were divided into two groups: the vascular mapping group and the control group. A comparative analysis of the re-operation rate between the two groups was determined by use of the chi-square rest, efficacy of preoperative US vascular mapping according to the type of surgery. A comparative analysis of the secondary patency after percutaneous transluminal angioplasty was determined by the use of Fischer exact test, and a comparative analysis of the diminution of patency during the follow-up periods was determined by the use of the Logrank test. In the mapping group, the diameters of intraoperatively selected vessels were investigated and compared with the recommended diameter on preoperative US vascular mapping determined statistically by the use of Fisher's exact test. The preoperative US vascular mapping group had relatively lower re-operation rates (11.8%) than the control group (28.1%) ({rho} = 0.09). The preventive role of US vascular mapping in more effective in decreasing the re-operation rate for a native arteriovenous fistula (7.4%) than for a synthetic arteriovenous graft (25.9%) ({rho} = 0.06). For patients than had an interventional procedure, the failure rate to obtain a secondary patency was smaller than in the mapping group (33.3%), compared with the control group (46.3%) ({rho} = 0.37). Patients in the mapping group had a higher patency than the control group patients for a native arteriovenous fistula (92.0%) and a synthetic arteriovenous graft (71.4%) at one year following surgery ({rho} = 0.10, {rho} = 0.79). The arteriovenous fistulas in the mapping group had a higher patency for both a native

  14. Percutaneous Intervention in Axillary Loop-Configured Arteriovenous Grafts for Chronic Hemodialysis Patients

    Energy Technology Data Exchange (ETDEWEB)

    Park, Beom Jin; Chung, Hwan Hoon; Sung, Deuk Jae; Park, Sang Joon; Son, Ho Sung; Jo, Sang Kyung; Kim, Yun Hwan; Cho, Sung Bum [College of Medicine, Korea University, Seoul (Korea, Republic of); Kim, Hyoung Rae [Kangwon National University, Chuncheon (Korea, Republic of)

    2010-04-15

    The purpose of this study was to evaluate the fistulographic features of malfunctioning axillary loop-configured arteriovenous grafts and the efficacy of percutaneous interventions in failed axillary loop-configured arteriovenous grafts. Ten patients with axillary loop-configured arteriovenous grafts were referred for evaluation of graft patency or upper arm swelling. Fistulography and percutaneous intervention, including thrombolysis, percutaneous transluminal angioplasty and stent placement, were performed. Statistical analysis of the procedure success rate and the primary and secondary patency rates was done. Four patients had graft related and subclavian venous stenosis, two patients had graft related stenosis and another four patients had subclavian venous stenosis only. Sixteen sessions of interventional procedures were performed in eight patients (average: 2 sessions / patient) until the end of follow-up. An interventional procedure was not done in two patients with central venous stenosis. The overall procedure success rate was 69% (11 of 16 sessions). The post-intervention primary and secondary patency rates were 50% and 63% at three months, 38% and 63% at six months and 25% and 63% at one year, respectively. Dysfunctional axillary loop-configured arteriovenous grafts almost always had subclavian venous and graft-related stenosis. Interventional treatments are helpful to overcome this and these treatments are expected to play a major role in restoring and maintaining the axillary loop-configured arteriovenous loop grafts

  15. Treatment of an Immature Autogenous Arteriovenous Fistula with Percutaneous Transluminal Angioplasty

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyoung Rae [Kangwon National University, Chuncheon (Korea, Republic of)

    2008-11-15

    The purpose of this study was to evaluate the efficacy of percutaneous transluminal angioplasty (PTA) in facilitating maturation of autogenous arteriovenous fistulae. There were 12 immature autogenous arteriovenous fistulae. We performed 15 PTAs transvenously. Post-intervention anatomic and clinical successes were estimated, and the 6-month and 1-year primary and secondary patency rates were calculated using Kaplan-Meier analysis. All immature fistulae had underlying stenosis (n=20): arteriovenous anastomosis (n=1) and venous outflow (n=19): 1) within 5 cm from the anastomosis (n=10); 2) more than 5 cm but less than 10 cm from the anastomosis (n=5); 3) more than 10 cm from the anastomosis, including central veins (n=4). Six fistulae had two or more stenoses. Repeat intervention was necessary in two patients. The anatomical success rate was 94.3%, and the clinical success rate was 86.7%. The 6-month and 1-year primary patency rates were 72.7% and 54.5%, and the secondary patency rates were 100% and 81.8%, respectively. All immature hemodialysis fistulae have underlying stenosis, most of which are located near the arteriovenous anastomosis. Early interventional procedures are helpful in the salvage and maintenance of immature arteriovenous fistulae, with a high degree of success

  16. Prevalence of pulmonary arteriovenous malformations (PAVMs) and occurrence of neurological symptoms in patients with hereditary haemorrhagic telangiectasia (HHT)

    DEFF Research Database (Denmark)

    Kjeldsen, A D; Oxhøj, H; Andersen, P E;

    2000-01-01

    Hereditary haemorrhagic telangiectasia (HHT) is a dominantly inherited disease. HHT is characterized by a wide variety of clinical manifestations, including pulmonary arteriovenous malformations (PAVMs) and neurological symptoms.......Hereditary haemorrhagic telangiectasia (HHT) is a dominantly inherited disease. HHT is characterized by a wide variety of clinical manifestations, including pulmonary arteriovenous malformations (PAVMs) and neurological symptoms....

  17. Risk factors associated with distal catheter migration following ventriculoperitoneal shunt placement.

    Science.gov (United States)

    Abode-Iyamah, Kingsley O; Khanna, Ryan; Rasmussen, Zachary D; Flouty, Oliver; Dahdaleh, Nader S; Greenlee, Jeremy; Howard, Matthew A

    2016-03-01

    Ventriculoperitoneal (VP) shunt placement is used to treat hydrocephalus. Shunt migration following VP shunt placement has been reported. The risk factors related to this complication have not been previously evaluated to our knowledge. In this retrospective cohort study, we aimed to determine risk factors leading to distal catheter migration and review the literature on the current methods of management and prevention. Adult patients undergoing VP shunt placement from June 2011 to December 2013 at a single institution were identified using electronic health records. The records were reviewed for demographic and procedural information, and subsequent treatment characteristics. The parameters of patients with distal shunt migration were compared to those undergoing new VP shunt placement for the same time period. We identified 137 patients undergoing 157 new VP shunt procedures with an average age of 57.7 ± standard deviation of 18.4 years old. There were 16 distal shunt migrations. Body mass index >30 kg/m(2) and number of previous shunt procedures were found to be independent risk factors for distal catheter migration. Obesity and number of previous shunt procedures were factors for distal catheter migration. Providers and patients should be aware of these possible risk factors prior to VP shunt placement.

  18. Control of an electromechanical hydrocephalus shunt--a new approach.

    Science.gov (United States)

    Elixmann, Inga M; Kwiecien, Monika; Goffin, Christine; Walter, Marian; Misgeld, Berno; Kiefer, Michael; Steudel, Wolf-Ingo; Radermacher, Klaus; Leonhardt, Steffen

    2014-09-01

    Hydrocephalus is characterized by an excessive accumulation of cerebrospinal fluid (CSF). Therapeutically, an artificial pressure relief valve (so-called shunt) is implanted which opens in case of increased intracranial pressure (ICP) and drains CSF into another body compartment. Today, available shunts are of a mechanical nature and drainage depends on the pressure drop across the shunt. According to the latest data, craniospinal compliance is considered to be even more important than mean ICP alone. In addition, ICP is not constant but varies due to several influences. In fact, heartbeat-related ICP waveform patterns depend on volume changes in the cranial vessels during a heartbeat and changes its shape as a function of craniospinal compliance. In this paper, we present an electromechanical shunt approach, which changes the CSF drainage as a function of the current ICP waveform. A series of 12 infusion tests in patients were analyzed and revealed a trend between the compliance and specific features of the ICP waveform. For waveform analysis of patient data, an existing signal processing algorithm was improved (using a Moore machine) and was implemented on a low-power microcontroller within the electromechanical shunt. In a test rig, the ICP waveforms were replicated and the decisions of the ICP analysis algorithm were verified. The proposed control algorithm consists of a cascaded integral controller which determines the target ICP from the measured waveform, and a faster inner-loop integral controller that keeps ICP close to the target pressure. Feedforward control using measurement data of the patient's position was implemented to compensate for changes in hydrostatic pressure during change in position. A model-based design procedure was used to lay out controller parameters in a simple model of the cerebrospinal system. Successful simulation results have been obtained with this new approach by keeping ICP within the target range for a healthy waveform.

  19. Experimental comparison of piezoelectric and magnetostrictive shunt dampers

    Science.gov (United States)

    Asnani, Vivake M.; Deng, Zhangxian; Scheidler, Justin J.; Dapino, Marcelo J.

    2016-04-01

    A novel mechanism called the vibration ring is being developed to enable energy conversion elements to be incorporated into the driveline of a helicopter or other rotating machines. Unwanted vibration is transduced into electrical energy, which provides a damping effect on the driveline. The generated electrical energy may also be used to power other devices (e.g., health monitoring sensors). PZT (`piezoceramic') and PMN-30%PT (`single crystal') stacks, as well as a Tb0.3Dy0.7Fe1.92 (`Terfenol-D') rod with a bias magnet array and a pickup coil, were tested as alternative energy conversion elements to use within the vibration ring. They were tuned for broadband damping using shunt resistors, and dynamic compression testing was conducted in a high-speed load frame. Energy conversion was experimentally optimized at 750Hz by tuning the applied bias stress and resistance values. Dynamic testing was conducted up to 1000Hz to determine the effective compressive modulus, shunt loss factor, internal loss factor, and total loss factor. Some of the trends of modulus and internal loss factor versus frequency were unexplained. The single crystal device exhibited the greatest shunt loss factor whereas the Terfenol-D device had the highest internal and total loss factors. Simulations revealed that internal losses in the Terfenol-D device were elevated by eddy current effects, and an improved magnetic circuit could enhance its shunt damping capabilities. Alternatively, the Terfenol-D device may be simplified to utilize only the eddy current dissipation mechanism (no pickup coil or shunt) to create broadband damping.

  20. Surgical and transcatheter management alternatives in refractory pulmonary hypertension: Potts shunt.

    Science.gov (United States)

    Kula, Serdar; Atasayan, Vildan

    2015-10-01

    Despite advances in the medical treatment of children with pulmonary arterial hypertension that have resulted in improved health quality and life expectancy, the progression of the disease is still the main problem for some patients. Because of this undesirable condition, the search for new treatment strategies continues for pediatric cardiologists. At this point, the Eisenmenger physiology is the main target because of the long-life expectancy and more stable hemodynamics of patients with Eisenmenger syndrome. Therefore, some invasive procedures may be used for conversion to Eisenmenger physiology with the aim of decompressing the right ventricle.

  1. Peroral extrusion of ventriculoperitoneal shunt: Case report and review of literature

    Directory of Open Access Journals (Sweden)

    Sridhar K

    2009-01-01

    Full Text Available A rare complication of ventriculoperitoneal shunting (VPS is bowel perforation by the peritoneal catheter of the shunt tube. Rarer still is the peroral extrusion of such a perforated shunt. A two-month-old infant with history of neonatal meningitis, presented with a large head, bulging fontanelle, and hydrocephalus. A VPS was inserted. The child was doing well till the age of eight months, when following vomiting, the peritoneal end of the shunt came out through the mouth. The shunt was removed and antibiotics started. At follow up after 12 months, the child was doing well. Peroral extrusion of the shunt tube needs prompt treatment, including removal of the extruded shunt tube, and attention to bowel perforation and possible cerebrospinal fluid infection. The reported patient is younger than the five cases reported earlier. Strategies in the management of this complication are reviewed. An individualized approach is essential for the successful treatment of this rare complication.

  2. Shunt implantations and peritoneal catheters: Do not cut beyond 20 cm

    Directory of Open Access Journals (Sweden)

    Angelo Luiz Maset

    2014-01-01

    Full Text Available Background: Ventriculoperitoneal shunts are supplied with long peritoneal catheters, most commonly between 80 and 120 cm long. ISO/DIS 7197/2006 [15] shunt manufacturing procedures include peritoneal catheter as an integrate of the total resistance. Cutting pieces of peritoneal catheters upon shunt implantation or revision is a common procedure. Methods: We evaluated five shunts assembled with different total pressure resistances and variable peritoneal catheter lengths in order to clarify the changes that occurred in the hydrodynamic profile when peritoneal catheters were cut upon shunt implantation or shunt revision. Results: Originally, all shunts performed within the operational range. Shunt 1 performed in a lower pressure range at 200 mm cut off peritoneal catheter and as a low-pressure shunt with -300 mm cut off. Shunt 2 was manufactured to run at the higher border pressure range, and it went out of specification with a 300 mm cut off. Shunt 3 was manufactured to run close to the lower border pressure range, and at 100 mm cutoff, it was already borderline in a lower resistive category. Other shunts also responded similarly. Conclusion: The limit to maintain a shunt in its original pressure settings was 20 cm peritoneal catheter cutting length. By cutting longer pieces of peritoneal catheter, one would submit patients to a less-resistive regimen than intended and his reasoning will be compromised. The pediatric population is more prone to suffer from the consequences of cutting catheters. Shunt manufacturers should consider adopting peritoneal catheters according to the age (height of the patient.

  3. An experimental in-vivo canine model for adult shunt infection

    Directory of Open Access Journals (Sweden)

    Procop Gary

    2008-10-01

    Full Text Available Abstract Background Detailed human studies of the mechanisms and development of shunt infection in real time are not possible, and we have developed a canine hydrocephalus model to overcome this. The intention of this pilot study was to show that the canine hydrocephalus model could be shunted using conventional "human" shunts, and that a shunt infection could be established so that further studies could then be planned. Methods Hydrocephalus was induced in seven dogs (Canis familiaris by fourth ventricle obstruction. Four weeks later they were shunted using a Hakim Precision valve. Four of the dogs received shunts whose ventricular catheter had been inoculated with Staphylococcus epidermidis, and three were uninoculated controls. Four weeks after shunting the dogs were sacrificed and necropsy was performed. Removed shunts and tissue samples were examined microbiologically and isolates were subjected to detailed identification and genomic comparison. Results All the dogs remained well after shunting. Examination of removed shunt components revealed S. epidermidis in the brain and throughout the shunt system in the four inoculated animals, but in two of these Staphylococcus intermedius was also found. S. intermedius was also isolated from all three "negative" controls. There were slight differences between S. intermedius strains suggesting endogenous infection rather than cross- infection from a point source. Conclusion Shunt infection was established in the canine model, and had the experiment been extended beyond four weeks the typical microbiological, pathological and clinical features might have appeared. The occurrence of unplanned shunt infections in control animals due to canine normal skin flora reflects human clinical experience and underlines the usual source of bacteria causing shunt infection.

  4. Stereotactic radiosurgery for intracranial arteriovenous malformations: A review

    Directory of Open Access Journals (Sweden)

    Ranjith K Moorthy

    2015-01-01

    Full Text Available Stereotactic radiosurgery (SRS has proven to be an effective strategy in the management of intracranial arteriovenous malformations (AVMs in children and adults over the past three decades. Its application has resulted in lowering the morbidity and mortality associated with treatment of deep-seated AVMs. SRS has been used as a primary modality of therapy as well as in conjunction with embolization and microsurgery in the management of AVMs. The obliteration rate after SRS has been reported to range from 35% to 92%. Smaller AVMs receiving higher marginal doses have obliteration rates of 70% and more. The median follow-up reported in most series is approximately 36–40 months. The median time to obliteration has been reported to be approximately 24–36 months in most series. Radiation-induced neurological complications have been reported in less than 10% of patients, with a 1.5%–6% risk of developing a new permanent neurological deficit. The bleeding rate during the latency to obliteration has been reported to be approximately 5%. This review describes the experience reported in literature with respect to the indications, dosage, factors affecting obliteration rate of AVMs, and complications after SRS.

  5. Endovascular and microsurgical treatment of cerebral arteriovenous malformations: Current recommendations

    Science.gov (United States)

    Conger, Andrew; Kulwin, Charles; Lawton, Michael T.; Cohen-Gadol, Aaron A.

    2015-01-01

    Background: Cerebral arteriovenous malformations (AVMs) can be a heterogeneous pathological entity whose management requires a complex decision-making process due to the risks associated with their treatment and natural history. Despite the recently published conclusions of the aborted Randomized Trial of Brain Unruptured AVMs (ARUBA) trial, the authors of this article believe multimodality intervention in general and microsurgical resection in particular continue to play a major role in the management of carefully selected ruptured or unruptured AVMs. Methods: The authors provide an overview of their methodology for endovascular intervention and microsurgical resection and share their technical nuances for successful embolization and microsurgical resection of AVMs with special emphasis on complication avoidance. Results: The authors have achieved successful outcomes in embolization and resection of cerebral AVMs when using their methodology. Conclusions: These lesions are among the most technically difficult pathological entities handled by the cerebrovascular specialist, and an overview of technical concepts to help systematize this challenging and variable endeavor can improve the safety of their treatment. PMID:25883831

  6. Brain Abscesses Associated with Asymptomatic Pulmonary Arteriovenous Fistulas

    Science.gov (United States)

    Nam, Taek-Kyun; Park, Yong-sook; Kwon, Jeong-taik

    2017-01-01

    Brain abscess commonly occurs secondary to an adjacent infection (mostly in the middle ear or paranasal sinuses) or due to hematogenous spread from a distant infection or trauma. Pulmonary arteriovenous fistulas (AVFs) are abnormal direct communications between the pulmonary artery and vein. We present two cases of brain abscess associated with asymptomatic pulmonary AVF. A 65-year-old woman was admitted with a headache and cognitive impairment that aggravated 10 days prior. An magnetic resonance (MR) imaging revealed a brain abscess with severe edema in the right frontal lobe. We performed a craniotomy and abscess removal. Bacteriological culture proved negative. Her chest computed tomography (CT) showed multiple AVFs. Therapeutic embolization of multiple pulmonary AVFs was performed and antibiotics were administered for 8 weeks. A 45-year-old woman presented with a 7-day history of progressive left hemiparesis. She had no remarkable past medical history or family history. On admission, blood examination showed a white blood cell count of 6290 cells/uL and a high sensitive C-reactive protein of 2.62 mg/L. CT and MR imaging with MR spectroscopy revealed an enhancing lesion involving the right motor and sensory cortex with marked perilesional edema that suggested a brain abscess. A chest CT revealed a pulmonary AVF in the right upper lung. The pulmonary AVF was obliterated with embolization. There needs to consider pulmonary AVF as an etiology of cerebral abscess when routine investigations fail to detect a source. PMID:28061502

  7. Chronic kidney disease aggravates arteriovenous fistula damage in rats.

    Science.gov (United States)

    Langer, Stephan; Kokozidou, Maria; Heiss, Christian; Kranz, Jennifer; Kessler, Tina; Paulus, Niklas; Krüger, Thilo; Jacobs, Michael J; Lente, Christina; Koeppel, Thomas A

    2010-12-01

    Neointimal hyperplasia (NIH) and impaired dilatation are important contributors to arteriovenous fistula (AVF) failure. It is unclear whether chronic kidney disease (CKD) itself causes adverse remodeling in arterialized veins. Here we determined if CKD specifically triggers adverse effects on vascular remodeling and assessed whether these changes affect the function of AVFs. For this purpose, we used rats on a normal diet or on an adenine-rich diet to induce CKD and created a fistula between the right femoral artery and vein. Fistula maturation was followed noninvasively by high-resolution ultrasound (US), and groups of rats were killed on 42 and 84 days after surgery for histological and immunohistochemical analyses of the AVFs and contralateral femoral vessels. In vivo US and ex vivo morphometric analyses confirmed a significant increase in NIH in the AVFs of both groups with CKD compared to those receiving a normal diet. Furthermore, we found using histological evaluation of the fistula veins in the rats with CKD that the media shrank and their calcification increased significantly. Afferent artery dilatation was significantly impaired in CKD and the downstream fistula vein had delayed dilation after surgery. These changes were accompanied by significantly increased peak systolic velocity at the site of the anastomosis, implying stenosis. Thus, CKD triggers adverse effects on vascular remodeling in AVFs, all of which contribute to anatomical and/or functional stenosis.

  8. Absolute Ethanol Embolization of Arteriovenous Malformations in the Periorbital Region

    Energy Technology Data Exchange (ETDEWEB)

    Su, Li-xin, E-mail: sulixin1975@126.com [Shanghai Jiao Tong University School of Medicine, Department of Oral and Maxillofacial & Head and Neck Oncology, Ninth People’s Hospital (China); Jia, Ren-Bing, E-mail: jrb19760517@hotmail.com [Shanghai Jiao Tong University School of Medicine, Department of Ophthalmology, Ninth People’s Hospital (China); Wang, De-Ming, E-mail: wdmdeming@hotmail.com; Lv, Ming-Ming, E-mail: lvmingming001@163.com; Fan, Xin-dong, E-mail: fanxindong@aliyun.com [Shanghai Jiao Tong University School of Medicine, Department of Radiology, Ninth People’s Hospital (China)

    2015-06-15

    ObjectiveArteriovenous malformations (AVMs) involving the periorbital region are technically challenging clinical entities to manage. The purpose of the present study was to present our initial experience of ethanol embolization in a series of 16 patients with auricular AVMs and assess the outcomes of this treatment.MethodsTranscatheter arterial embolization and/or direct percutaneous puncture embolization were performed in the 16 patients. Pure or diluted ethanol was manually injected. The follow-up evaluations included physical examination and angiography at 1- to 6-month intervals.ResultsDuring the 28 ethanol embolization sessions, the amount of ethanol used ranged from 2 to 65 mL. The obliteration of ulceration, hemorrhage, pain, infection, pulsation, and bruit in most of the patients was obtained. The reduction of redness, swelling, and warmth was achieved in all the 16 patients, with down-staging of the Schobinger status for each patient. AVMs were devascularized 100 % in 3 patients, 76–99 % in 7 patients, and 50–75 % in 6 patients, according to the angiographic findings. The most common complications were necrosis and reversible blister. No permanent visual abnormality was found in any of the cases.ConclusionEthanol embolization is efficacious and safe in the treatment of AVMs in the periorbital region and has the potential to be accepted as the primary mode of therapy in the management of these lesions.

  9. Arterio-venous fistula following a lumbar disc surgery

    Directory of Open Access Journals (Sweden)

    Thanyani V Mulaudzi

    2011-01-01

    Full Text Available Vascular complications during posterior lumbar disc surgery are rare and its presentation with varicose veins is even rarer. A 23 year-old male patient presented with large varicose veins in right lower limb. He underwent a posterior lumbar spine discectomy surgery. He noticed mild swelling of the distal third right lower limb 3 months after index surgery and reported 6 months later when he developed varicose veins. Duplex Doppler confirmed varicose veins of the long saphenous vein and its tributaries with a patent deep venous system. A digital subtraction angiogram demonstrated a large right common iliac artery (CIA false aneurysm with an arteriovenous fistula between right common iliac vessels. He had a right CIA covered stent insertion with good results. Varicose veins were later managed with sapheno-femoral junction ligation and a below knee long saphenous vein stripping. At six month follow-up the lower limb swelling had completely recovered and duplex ultrasound did not show any recurrence of varicose veins.

  10. Systemic-pulmonary artery shunts in infants: modified Blalock-Taussig and central shunt procedures.

    Science.gov (United States)

    Brooks, Andre

    2014-01-01

    Access is gained through a midline sternotomy, the thymus partially excised and the superior part of the pericardium is opened. The innominate vein is retracted and the innominate artery is mobilized up to the bifurcation. The aorta is retracted to the left, the superior vena cavae to the right and the right atrial appendage inferiorly. The adventitia around the right pulmonary artery (PA) is dissected, taking care to incise the bulky pericardial reflection between the superior vena cavae and the trachea. Heparin is administrated. An occlusive clamp is applied to the right PA to test for haemodynamic tolerance prior to proceeding with the interposition of a suitable size artificial vascular prosthesis, based on the weight of the patient, between the innominate artery, or proximal subclavian artery and the right PA. Alternatively, if a sufficient main PA is present and adequate flow from a patent ductus arteriosus an end-to-side interposition shunt may be constructed between the ascending aorta and the main PA, provided the patient is stable with the test occlusion of the main PA. The management of the patent arterial ductus depends on whether or not there is forward flow through the PA.

  11. A Case Report of Coronary Arteriovenous Fistulas with an Unruptured Coronary Artery Aneurysm Successfully Treated by Surgery

    Directory of Open Access Journals (Sweden)

    Nobuhiro Takeuchi

    2012-01-01

    Full Text Available A 58-year-old female with a history of Wolff-Parkinson-White syndrome presented at our institution with palpitations and chest pain. Electrocardiography revealed paroxysmal supraventricular tachycardia with a heart rate of 188 beats/min. Antiarrhythmic drugs were ineffective, and tachycardia was resolved by electrical cardioversion. Transthoracic echocardiography revealed abnormal vessels around the right coronary artery (RCA and pulmonary artery (PA; in addition, we suspected coronary arteriovenous fistula (CAVF. Coronary angiography and coronary computed tomography revealed dilated fistula vessels, with a 1 cm saccular aneurysm around the RCA, originating from the proximal RCA and left anterior descending artery into the main trunk of PA. Therefore, we confirmed the diagnosis of CAVF with an unruptured aneurysm. We surgically ligated and clipped the fistula vessels and resected the aneurysm. The resected aneurysm measured  cm in size. Pathological examination of the resected aneurysm revealed hypertrophic walls comprising proliferating fibroblasts cells thin elastic fibers. Very few atherosclerotic changes manifested in the aneurysm walls. We report the case of a patient with CAVF and an unruptured coronary artery aneurysm who was successfully treated by surgery.

  12. Hybrid management of a spontaneous ilio-iliac arteriovenous fistula: a case report

    LENUS (Irish Health Repository)

    O'Brien, Gavin C

    2011-08-22

    Abstract Introduction Spontaneous iliac arteriovenous fistulae are a rare clinical entity. Such localized fistulation is usually a result of penetrating traumatic or iatrogenic injury. Clinical presentation can vary greatly but commonly includes back pain, high-output congestive cardiac failure and the presence of an abdominal bruit. Diagnosis, therefore, is often incidental or delayed. Case presentation We report a case of a spontaneous ilio-iliac arteriovenous fistula in a 68-year-old Caucasian man detected following presentation with unilateral claudication and congestive cardiac failure. Following computed tomography evaluation, the fistula was successfully treated with a combined endovascular (aorto-uni-iliac device) and open (femoro-femoral crossover) approach. Conclusion Endovascular surgery has revolutionized the management of such fistulae and we report an interesting case of a high-output iliac arteriovenous fistulae successfully treated with a hybrid vascular approach.

  13. Immunohistochemical study in dural arteriovenous fistula and possible role of ephrin-B2 for development of dural arteriovenous fistula

    Institute of Scientific and Technical Information of China (English)

    Wuttipong Tirakotai 王宝隆; BIAN Liu-guan 卞留贯; Helmut Bertalanffy; Siegfried Bien; Ulrich Sure

    2004-01-01

    Background Although there were several clinical and experimental studies discussing the pathogenesis of dural arteriovenous fistula (DAVF), the pathological process leading to intracranial DAVF so far remains unknown. In this study, we investigated the expression of vascular growth factors in order to elucidate the possible role of these factors for the development of DAVF and to study the biological activity of this uncommon lesion.Methods We examined the histological features, proliferative and angiogenic capacities of the tissue specimens obtained from 6 patients who underwent surgery at our institution. Immunohistochemical staining for vascular endothelial growth factor (VEGF), its receptors Flk-1 and Flt-1, ephrin-B2, MIB-1 and proliferating cell nuclear antigen (PCNA) was performed using standard immunohistochemical techniques. Results A positive immunostaining was found for all antibodies studied except MIB-1, whereas nuclear endothelial expression of PCNA was observed in only 3/6 cases. VEGF stained positive in all of the available specimens (6/6). Flk-1 showed a positive immunoreaction in only 2/6 cases and Flt-1 in 4/6 cases. Ephrin-B2 was expressed in the majority (5/6) of the cases.Conclusions These results support the hypothesis that DAVFs might be acquired dynamic vascular malformations with low biological activity. Vascular growth factors like VEGF and ephrin-B2 might play a pivotal role in the formation of DAVF.

  14. Intracranial arteriovenous malformation and dural arteriovenous fistula embedded in a meningioma—case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Moujahed Labidi

    2015-12-01

    Full Text Available The association between a vascular malformation and a meningioma is a rare occurrence intracranially. We document the case of a 59-year-old man who presented with a right parietal extra-axial mass with headaches and seizures. Hemangiopericytoma was initially suspected on the basis of an unusual vascular pattern and rapid lesion progression. Angiography revealed abnormal vessels and an early draining vein associated with the mass. Arterial feeders were primarily from the middle cerebral artery with discrete contribution from both middle meningeal arteries. Craniotomy and Simpson 0 resection of the lesion were undertaken and revealed the coexistence of a dural based tumor with an AVM and a dural arteriovenous fistula (dAVF. Histology and immunohistochemistry were consistent with the diagnosis of meningioma and associated AVM. This case represents the eleventh report of an AVM associated with a meningioma, among which only 6 were contiguous. Such cases illustrate the pathogenic roles of angiogenesis and inflammation that is common to AVMs, dAVF and meningiomas.

  15. The orbital volume measurement in patients with ventriculoperitoneal shunt.

    Science.gov (United States)

    Kim, Jong-Min; Chang, Moo-Hwan; Kyung, Sungeun E

    2015-01-01

    Enophthalmos occurs from the increased bony volume or decreased soft tissue volume in the orbit and can be caused in patients with long-term ventriculoperitoneal (VP) shunt. This study tried to find out the change of orbital volume by measuring the orbital volume before and after operation in adult patients who underwent VP shunt for hydrocephalus. The 2 evaluators measured orbital volume by using ITK-SNAP 2.4 program with double-blind test for computed tomography images before and after operation targeting 36 patients over the age of 18 who underwent VP shunt with pressure-controlled valve from 2003 to 2011. Wilcoxon matched-pairs signed-rank test of GraphPad software was used to statistically analyze the difference in orbital volume change before and after operation. In case of mean pre-op orbital volume of total 36 patients, the right was measured as 23.72 ± 4.65 cm(3), the left as 23.47 ± 4.61 cm(3), the post-op right as 24.67 ± 4.70 cm(3), and the left as 24.18 ± 4.63 cm(3), showing no statistically significant difference (P = 0.106). The mean pre-op orbital volume of 14 people (28 eyes) followed for more than 11 months was 25.06 ± 4.58 cm(3) in the right and 24.4 ± 5.02 cm(3) in the left and the mean post-op orbital volume was 27.0 ± 4.28 cm(3) in the right and 25.76 ± 3.92 cm(3) in the left, showing statistically significant differences in the change of the volume before and after shunt operation (P = 0.0057). In patients who maintain long-term shunt devices after VP shunt, remodeling of matured orbital bone may be caused due to the change in pressure gradient between cranial cavity and orbit and the possible occurrence of resulting secondary enophthalmos by increased orbital volume should be considered.

  16. Arteriovenous fistula and pseudoaneurysm as complications of renal biopsy treated with percutaneous intervention

    Institute of Scientific and Technical Information of China (English)

    JIANG Wen-xia; WANG Hui-fang; MA Jun; HAN Hong-jie

    2010-01-01

    @@ Symptomatic arteriovenous fistula (AVF) with pseudoaneurysm after percutaneous renal biopsy is an uncommon anomaly, occurring from 0.34% to 6.3%.1Most of these vascular lesions are of little clinical importance. However, severe bleeding,2 persistent hematuria, or acute urinary retention may occur, requiring treatment. Here we report a case of gross hematuria and acute urinary retention after renal biopsy in a male patient.An arteriovenous fistula with pseudoaneurysm was detected by renal ultrasound, confirmed by angiography and then successfully treated by transcatheter arterial embolization3 without damage to renal parenchyma.

  17. Endovascular repair of traumatic arteriovenous fistula between axillary artery and vein

    Institute of Scientific and Technical Information of China (English)

    Mo Ansheng

    2014-01-01

    Traumatic arteriovenous fistula between the axillary artery and vein may present a difficult problem in treatment.There are few reports demonstrating the endovascular repair of this challenge.Herein,we present such a case of endovascular repair of traumatic arteriovenous fistula between the axillary artery and vein with false aneurysm formation.The patient was discharged 1 1 days after successful operation.Oral clopidogrel and aspirin were administerted for 18 months.At one year follow-up,the patient was in good condition and showed no evidence of neurological deficit in the left upper limb.

  18. Sumatriptan does not affect arteriovenous oxygen differences in jugular and cubital veins in normal human subjects

    DEFF Research Database (Denmark)

    Wienecke, T.; Hansen, J.M.; Petersen, J.;

    2008-01-01

    Arteriovenous anastomoses (AVAs) may open up during migraine attacks. In studies with anaesthetized and bilaterally vagosympatectomized pigs, triptans reduce AVA blood flow and increase the arteriovenous O-2 difference (AVDO(2)). To investigate whether subcutaneous sumatriptan 6 mg could induce...... changes in the AVDO(2), we measured the AVDO(2) in the external jugular vein in healthy subjects. We also measured the AVDO(2) in the internal jugular and cubital veins. There were no changes in AVDO(2) after subcutaneous sumatriptan, probably because AVA blood flow is limited in humans with an intact...

  19. Arterial desaturation due to pulmonary arteriovenous malformations after the Kawashima Operation

    Directory of Open Access Journals (Sweden)

    Rohit S Loomba

    2016-01-01

    Full Text Available Arterial desaturation may occur after the Kawashima procedure and, in the absence of venovenous collaterals is usually due to pulmonary arteriovenous malformations. Stenting of the pulmonary arteries, oxygen therapy, and pulmonary vasodilators such as sildenafil have not been able to resolve the arterial desaturation and the only way to do this has been Fontan completion. The time course of the formation of these malformations after the Kawashima and the progression of cyanosis and its resolution after the Fontan has only been demonstrated in case reports and small case series. We pool the available data to model arterial saturations in patients with pulmonary arteriovenous malformations after the Kawashima procedure.

  20. Assessment of Novel Anti-thrombotic Fusion Proteins for Inhibition of Stenosis in a Porcine Model of Arteriovenous Graft.

    Directory of Open Access Journals (Sweden)

    Christi M Terry

    Full Text Available Hemodialysis arteriovenous synthetic grafts (AVG provide high volumetric blood flow rates shortly after surgical placement. However, stenosis often develops at the vein-graft anastomosis contributing to thrombosis and early graft failure. Two novel fusion proteins, ANV-6L15 and TAP-ANV, inhibit the tissue factor/factor VIIa coagulation complex and the factor Xa/factor Va complex, respectively. Each inhibitor domain is fused to an annexin V domain that targets the inhibitor activity to sites of vascular injury to locally inhibit thrombosis. This study's objective was to determine if these antithrombotic proteins are safe and effective in inhibiting AVG stenosis.A bolus of either TAP-ANV or ANV-6L15 fusion protein was administered intravenously immediately prior to surgical placement of a synthetic graft between the external jugular vein and common carotid artery in a porcine model. At surgery, the vein and artery were irrigated with the anti-thrombotic fusion protein. Control animals received intravenous heparin. At 4 weeks, MRI was performed to evaluate graft patency, the pigs were then euthanized and grafts and attached vessels were explanted for histomorphometric assessment of neointimal hyperplasia at the vein-graft anastomosis. Blood was collected at surgery, immediately after surgery and at euthanasia for serum metabolic panels and coagulation chemistries.No acute thrombosis occurred in the control group or in either experimental group. No abnormal serum chemistries, activated clotting times or PT, PTT values were observed after treatment in experimental or control animals. However, at the vein-graft anastomosis, there was no difference between the control and experimental groups in cross-sectional lumen areas, as measured on MRI, and no difference in hyperplasia areas as determined by histomorphometry. These results suggest that local irrigation of TAP-ANV or ANV-6L15 intra-operatively was as effective in inhibiting acute graft thrombosis

  1. Arterio-venous fistula for automated red blood cells exchange in patients with sickle cell disease: Complications and outcomes.

    Science.gov (United States)

    Delville, Marianne; Manceau, Sandra; Ait Abdallah, Nassim; Stolba, Jan; Awad, Sameh; Damy, Thibaud; Gellen, Barnabas; Sabbah, Laurent; Debbache, Karima; Audard, Vincent; Beaumont, Jean-Louis; Arnaud, Cécile; Chantalat-Auger, Christelle; Driss, Françoise; Lefrère, François; Cavazzana, Marina; Franco, Gilbert; Galacteros, Frederic; Ribeil, Jean-Antoine; Gellen-Dautremer, Justine

    2017-02-01

    Erythrocytapheresis (ER) can improve outcome in patients with sickle cell disease (SCD). A good vascular access is required but frequently it can be difficult to obtain for sickle cell patients. Arterio-venous fistulas (AVFs) have been suggested for ER in SCD supported by limited evidence. We report the largest cohort of ER performed with AVFs from three French SCD reference centers. Data of SCD patients undergoing ER with AVFs in the French SCD reference center were retrospectively collected. The inclusion criteria were: SS or Sβ-Thalassemia and AVF surgery for ER. SCD-related complications, transfusion history, details about AVF surgical procedure, echocardiographic data before and after AVF, AVF-related surgical and hemodynamical complications were collected. Twenty-six patients (mean age 20.5 years, mean follow-up 68 months [11-279]) were included. Twenty-three patients (88.5%) required central vascular access before AVF. Fifteen AVFs (58%) were created on the forearm and 11 (42%) on the arm. Nineteen patients (73%) had stenotic, thrombotic or infectious AVF complications. A total of 0.36 stenosis per 1,000 AVF days, 0.37 thrombosis per 1,000 AVF days and 0.078 infections per 1.000 AVF days were observed. The mean AVF lifespan was 51 months [13-218]. One patient with severe pulmonary hypertension worsened after AVF creation and died. We report the first series of SCD patients with AVF for ER, demonstrating that AVFs could be considered as a potential vascular access for ER. Patients with increased risk for hemodynamic intolerance of AVFs must be carefully identified, so that alternative vascular accesses can be considered. Am. J. Hematol. 92:136-140, 2017. © 2016 Wiley Periodicals, Inc.

  2. Emergency Portacaval Shunt Versus Rescue Portacaval Shunt in a Randomized Controlled Trial of Emergency Treatment of Acutely Bleeding Esophageal Varices in Cirrhosis—Part 3

    Science.gov (United States)

    Isenberg, Jon I.; Wheeler, Henry O.; Haynes, Kevin S.; Jinich-Brook, Horacio; Rapier, Roderick; Vaida, Florin; Hye, Robert J.

    2010-01-01

    Background Emergency treatment of bleeding esophageal varices in cirrhosis is of singular importance because of the high mortality rate. Emergency portacaval shunt is rarely used today because of the belief, unsubstantiated by long-term randomized trials, that it causes frequent portal-systemic encephalopathy and liver failure. Consequently, portacaval shunt has been relegated solely to salvage therapy when endoscopic and pharmacologic therapies have failed. Question: Is the regimen of endoscopic sclerotherapy with rescue portacaval shunt for failure to control bleeding varices superior to emergency portacaval shunt? A unique opportunity to answer this question was provided by a randomized controlled trial of endoscopic sclerotherapy versus emergency portacaval shunt conducted from 1988 to 2005. Methods Unselected consecutive cirrhotic patients with acute bleeding esophageal varices were randomized to endoscopic sclerotherapy (n = 106) or emergency portacaval shunt (n = 105). Diagnostic workup was completed and treatment was initiated within 8 h. Failure of endoscopic sclerotherapy was defined by strict criteria and treated by rescue portacaval shunt (n = 50) whenever possible. Ninety-six percent of patients had more than 10 years of follow-up or until death. Results Comparison of emergency portacaval shunt and endoscopic sclerotherapy followed by rescue portacaval shunt showed the following differences in measurements of outcomes: (1) survival after 5 years (72% versus 22%), 10 years (46% versus 16%), and 15 years (46% versus 0%); (2) median post-shunt survival (6.18 versus 1.99 years); (3) mean requirements of packed red blood cell units (17.85 versus 27.80); (4) incidence of recurrent portal-systemic encephalopathy (15% versus 43%); (5) 5-year change in Child’s class showing improvement (59% versus 19%) or worsening (8% versus 44%); (6) mean quality of life points in which lower is better (13.89 versus 27.89); and (7) mean cost of care per

  3. Endoscopic third ventriculostomy has no higher costs than ventriculoperitoneal shunt

    Directory of Open Access Journals (Sweden)

    Benicio Oton de Lima

    2014-07-01

    Full Text Available Objective: To evaluate the cost of endoscopic third ventriculostomy (ETV compared to ventriculoperitoneal shunt (VPS in the treatment of hydrocephalus in children. Method: We studied 103 children with hydrocephalus, 52 of which were treated with ETV and 51 with VPS in a prospective cohort. Treatment costs were compared within the first year after surgery, including subsequent surgery or hospitalization. Results: Twenty (38.4% of the 52 children treated with VPS needed another procedure due to shunt failure, compared to 11 (21.5% of 51 children in the ETV group. The average costs per patient in the group treated with ETV was USD$ 2,177,66±517.73 compared to USD$ 2,890.68±2,835.02 for the VPS group. Conclusions: In this series there was no significant difference in costs between the ETV and VPS groups.

  4. A Technique for Shunt Active Filter meld micro grid System

    Directory of Open Access Journals (Sweden)

    A. Lumani

    2015-08-01

    Full Text Available The proposed system presents a control technique for a micro grid connected hybrid generation system ith case study interfaced with a three phase shunt active filter to suppress the current harmonics and reactive power present in the load using PQ Theory with ANN controller. This Hybrid Micro Grid is developed using freely renewable energy resources like Solar Photovoltaic (SPV and Wind Energy (WE. To extract the maximum available power from PV panels and wind turbines, Maximum power point Tracker (MPPT has been included. This MPPT uses the “Standard Perturbs and Observe” technique. By using PQ Theory with ANN Controller, the Reference currents are generated which are to be injected by Shunt active power filter (SAPFto compensate the current harmonics in the non linear load. Simulation studies shows that the proposed control technique performs non-linear load current harmonic compensation maintaining the load current in phase with the source voltage.\\

  5. Integrating rolling stock scheduling with train unit shunting

    DEFF Research Database (Denmark)

    Haahr, Jørgen Thorlund; Lusby, Richard Martin

    2017-01-01

    In this paper, we consider integrating two important railway optimization problems, in particular the Rolling Stock Scheduling Problem and the Train Unit Shunting Problem. We present two similar branch-and-cut based approaches to solve this integrated problem and, in addition, provide a comparison...... of different approaches to solve the so-called Track Assignment Problem, a subcomponent of the Train Unit Shunting problem. In this analysis we demonstrate, by way of a counter example, the heuristic nature of a previously argued optimal approach. For the integrated problem we analyze the performance...... of the proposed approaches on several real-life case studies provided by DSB S-tog, a suburban train operator in the greater Copenhagen area. Computational results confirm the necessity of the integrated approach; high quality solutions to the integrated problem are obtained on instances where a conventional...

  6. Surgical Management of Ascending Aortic Aneurysm and Its Complications

    Directory of Open Access Journals (Sweden)

    Sisira Sran

    2014-01-01

    Full Text Available Ascending aortic aneurysms involving the proximal aortic arch, arising anywhere from the aortic valve to the innominate artery, represent various problems in which open surgery is generally required. Surgical options include excision of the aortic pathology or wrapping the aneurysm shell with an aortic Dacron graft. Intervention using the latter method can lead to extravasation of blood along the suture lines resulting in continuous bleeding within the periprosthetic space. The Cabrol technique was developed as a method for decompression of postoperative leaks by the formation of a conduit system from the periprosthetic space to the right atrium. The coronary ostia are anastomosed to a second graft in an end-to-end fashion, which is then anastomosed to the ascending aortic conduit side to side. The native aorta is then sewn around the prosthesis, hereby creating a shunt to drain anastomotic leakage. This shunt reduces postsurgical risk of pseudoaneurysm formation and normally closes a few days following surgery. We discuss the case of a patient who underwent Cabrol’s variation and six months later was demonstrated to have a patent shunt.

  7. Radiologic diagnosis and treatment of iatrogenic acquired uterine arteriovenous malformation

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Jung Hyeok [College of Medicine, Keimyung Univ., Taegu (Korea, Republic of)

    2002-05-01

    To analyze gray-scale US, color and duplex Doppler US, and angiographic findings in patients with acquired uterine arteriovenous malformations (AVMs), and to evaluate the usefulness of these modalities in the diagnosis of this disease and the effect of transcatheter arterial embolization in its treatment. During a recent seven-year period, we diagnosed 21 cases of acquired uterine AVM. Nineteen of these patients had a history of causative D and C (between one and seven D and C procedures per patient), one had a history of causative cesarean section, and one had cervical conization. All patients underwent transabdominal and endovaginal gray-scale, color Doppler, and duplex Doppler US and angiography, with therapeutic embolization of bilateral uterine arteries. The majority underwent follow-up Doppler US after embolization. The gray-scale US morphology of uterine AVMs included subtle myometrial inhomogeneity and multiple distinct, small anechoic spaces in the thickened myometrium or endometrium. Color Doppler US showed a tangle of tortuous vessels with multidirectional, high-velocity arterial flow, which was focally or asymmetrically distributed. Duplex Doppler US depicted a waveform of fast arterial flow with low resistance, while angiography demonstrated a complex tangle of vessels supplied by enlarged uterine arteries, in association with early venous drainage during the arterial phase, and staiss of contrast medium within abnormal vasculature. Where AVMs were combined with a pseudoaneurysm, this finding was observed. Transcatheter arterial embolization provided a complete cure, without recurrence. Color and duplex Doppler US in an appropriate modality for the detection and diagnosis of uterine AVMs and for follow-up after embolization. Transcatheter arterial embolization is a safe and effective method of treating this disease.

  8. Autogenous Sapheonus Vein Graft Interposition in Arteriovenous Fistula Formation

    Directory of Open Access Journals (Sweden)

    Alper Uzun

    2013-10-01

    Full Text Available Aim: Other techniques are required due to the negative influence of poor superficial venous system calibration (<1.5-2 mm to the long term patency of the arteriovenous fistula which is documented via preoperative Doppler ultrasound examination. The postoperative outcome of 32 patients were compared prospectively whom autologous saphenous vein bridge graft was interposed between brachial artery/high brachial vein and radial artery/basilic vein. Material and Method: Patients were divided into two groups; patients whom radial artery/basilic vein autologous saphenous vein graft interposition was performed were labelled as Group 1 (17 patients while patients whom brachial artery/high brachial vein autologous saphenous vein graft was interpositioned were labelled as Group 2 (15 patients. Patients were followed up for 12 months. Graft related complications were recorded. Primary and secondary patency rate were calculated. Results: Graft infection, edema or ischemia of the hand or arm, congestive heart failure and mortality was not observed. There was not a significant difference in puncture site complications between two groups. Primary patency rate was 76.5% (13 of 17 in Group 1 while it was 93.3% (14 of 15 for Group 2 (p=0,185. Secondary patency rate was 82.4% (14 of 17 in Group1 and 100% (15 of 15 for Group 2 (p=0.093. Primary and secondary patency rate were similar between two groups. Discussion: We sought to compare the complication and patency rate of the proximal (brachial artery/high brachial vein and distal (radial artery/basilic vein located bridge graft interpositions and could not found statistical difference between two groups. It is reasonable to keep proximal regions for further interventions, so radial artery/basilic vein bridge graft interposition can be recommended as the initial option according to our findings.

  9. 急性颅内压增高时肺动静脉分流的意义%Change of pulmonary arteriovenous shunt following intracranial hypertension in dogs

    Institute of Scientific and Technical Information of China (English)

    林江凯; 王宪荣

    2003-01-01

    目的探讨颅内压增高对呼吸功能的影响.方法 16条犬分为高颅压组和对照组.高颅压组升高颅内压至8kPa(1kPa=7.5mm Hg),维持6h.两组均行肺动脉插管,动态测量肺分流量.结果颅内压增高后肺动脉压、肺血管阻力指数、肺泡动脉氧分压差显著增加;肺动静脉分流率(Qs/Qt)迅速从(9.70±4.83)%增加到(21.80±6.89)%(P<0.01).呼吸抑制、肺不张、肺水肿、肺部感染、肺血流动力变化共同参与颅内压增高后的肺分流增加.结论肺分流率是颅内压增高后呼吸功能不全的重要指标.

  10. Transient Hemolytic Anemia after Transjugular Intrahepatic Portosystemic Stent Shunt

    OpenAIRE

    Sagrario Garcia-Rebollo; Emilio González-Reimers; Francisco Santolaria-Fernández; Francisco Diaz-Romero; Fermin Rodriguez-Moreno; Antonio Martinez-Riera

    1996-01-01

    Management of variceal bleeding secondary to portal hypertension constitutes a challenging issue, particularly in child's C cirrhotic patients. Recently, transjugular placement of self-expanding metallic stents in the liver (TIPS), creating a shunt between the portal and hepatic branches has provided a safe and promising therapeutic approach in this clinical situation. We report here the case of a 66-year-old male cirrhotic patient who developed a moderately severe clinical picture of a Coomb...

  11. Resonance features of coupled Josephson junctions: radiation and shunting

    Science.gov (United States)

    Shukrinov, Yu M.; Seidel, P.; Il'ichev, E.; Nawrocki, W.; Grajcar, M.; Plecenik, P. A.; Rahmonov, I. R.; Kulikov, K.

    2012-11-01

    We study the phase dynamics and the resonance features of coupled Josephson junctions in layered superconductors and their manifestations in the current- voltage characteristics and temporal dependence of the electric charge in the superconducting layers. Results on the effect of the external radiation and shunting of the stack of Josephson junctions by LC-elements are presented. We discuss the ideas concerning the experimental observation of these resonances.

  12. External thoracic duct-venous shunt in conscious pigs for long term studies of connective tissue metabolites in lymph

    DEFF Research Database (Denmark)

    Jensen, L T; Olesen, H P; Risteli, J;

    1990-01-01

    An experimental animal model for lymph studies is described. Thoracic duct-venous shunt was established in 12 pigs. Shunt patency averaged 5.5 days. The composition of connective tissue metabolites in lymph and serum were investigated during a standardized surgical operation (thoracotomy) under g...... instead of dogs and sheep in studies on lymph. The effect of surgery/anesthesia must be taken into consideration....... general anesthesia. We measured the carboxyterminal propeptide of type I procollagen (PICP), the aminoterminal propeptide of type III procollagen (PIIINP) hyaluronan (HA) and total protein. During surgery/anesthesia lymph PICP (p less than 0.04), lymph PIIINP (p less than 0.03) and serum PIIINP (p less...... is a major route of tissue clearance for these components. The lymph/serum ratio of PICP was 1.0 in conscious pigs, indicating a direct release into the circulation. Total protein in lymph decreased (p less than 0.04) during surgery/anesthesia, whereas no changes were observed in serum. Pigs can be used...

  13. A case of repeated intracerebral hemorrhages secondary to ventriculoperitoneal shunt

    Directory of Open Access Journals (Sweden)

    Jinbing Zhao

    2015-03-01

    Full Text Available Ventriculoperitoneal shunt is a routinely performed treatment in neurosurgical department. Intracerebral hemorrhage, as a complication after shunt catheterization, is really rare but with high mortality. In this study, we reported a case of a 74-year-old man who suffered from repeated intracerebral hemorrhage after ventriculoperitoneal shunt. The first hemorrhage happened 63 h after the 1st surgery, and most hematomas were located in the ipsilateral occipital lobe and intraventricles, along the ventricular catheter. Fresh blood clot casts blocked the external ventricular draining catheter, which was inserted into the right front horn during the 3rd surgery, indicating new intraventricular bleeding happened. A large hematoma in ipsilateral frontal lobe was detected on the 3rd day after the removal of external ventricular draining catheter. Different hemorrhagic locations and time points were encountered on the same case. We discussed the possible causes of repeated hemorrhage for this case, and the pre-operative preparation including risk evaluation in future clinical work.

  14. Executive Function Improvement in Normal Pressure Hydrocephalus Following Shunt Surgery

    Directory of Open Access Journals (Sweden)

    Ezequiel Gleichgerrcht

    2009-01-01

    Full Text Available The aim of this investigation was to evaluate improvement of executive functions after shunt surgery in patients with early normal pressure hydrocephalus (NPH. Patients with NPH were assessed before and after shunt surgery with tests shown to be sensitive to damage to the prefrontal cortex (PFC. Significant differences were found between basal and follow-up performances on the Boston Naming Test, the backwards digits span, Part B of the Trail Making Test, and the number of words produced on the phonological fluency task. In conclusion, our study reveals that patients with NPH who respond positively to continuous slow lumbar cerebral spinal fluid drainage and receive a ventriculoperitoneal shunt implant, improve their performance on tasks of executive function. Due to the high demand for this form of mental processing in real-life complex scenarios, and based on the severe executive deficits present in both demented and non-demented NPH patients, we encourage the assessment of executive functions in this clinical group.

  15. Sodium Accumulation at Potential-Induced Degradation Shunted Areas in Polycrystalline Silicon Modules

    Energy Technology Data Exchange (ETDEWEB)

    Harvey, Steven P.; Aguiar, Jeffery A.; Hacke, Peter; Guthrey, Harvey; Johnston, Steve; Al-Jassim, Mowafak

    2016-11-01

    We investigated potential-induced degradation (PID) in silicon mini-modules that were subjected to accelerated stressing to induce PID conditions. Shunted areas on the cells were identified with photoluminescence and dark lock-in thermography (DLIT) imaging. The identical shunted areas were then analyzed via time-of-flight secondary-ion mass spectrometry (TOFSIMS) imaging, 3-D tomography, and high-resolution transmission electron microscopy. The TOF-SIMS imaging indicates a high concentration of sodium in the shunted areas, and 3-D tomography reveals that the sodium extends more than 2 um from the surface below shunted regions. Transmission electron microscopy investigation reveals that a stacking fault is present at an area identified as shunted by DLIT imaging. After the removal of surface sodium, tomography reveals persistent sodium present around the junction depth of 300 nm and a drastic difference in sodium content at the junction when comparing shunted and nonshunted regions.

  16. A RARE CASE OF BOWEL PERFORATION SECONDARY TO VENTRICULO PERITONEAL SHUNT

    Directory of Open Access Journals (Sweden)

    Aditya Pratap

    2014-10-01

    Full Text Available Bowel perforation is an unusual complication of ventriculo peritoneal shunt. We are presenting a case of 15 month old male child with the shunt tubing protruding through the anus associated with bowel perforation. This complication occurred after the 13 months of insertion of ventriculo peritoneal shunt for congenital hydrocephalus. There were no signs of meningitis but mild signs of peritonitis were present. At laparotomy the tube was seen to enter the sigmoid colon and was encapsulated by the greater omentum. The tube was cut and the distal end removed via the anus. Proximal part of shunt also removed because there was contralateral shunt present. Perforation was repaired. We are here in presenting a rare complication of VP shunt.

  17. Chemoembolic Hepatopulmonary Shunt Reduction to Allow Safe Yttrium-90 Radioembolization Lobectomy of Hepatocellular Carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Gaba, Ron C., E-mail: rgaba@uic.edu [University of Illinois Medical Center at Chicago, Department of Radiology, Section in Interventional Radiology (United States); VanMiddlesworth, Kyle A. [Midwestern University School of Medicine (United States)

    2012-12-15

    Yttrium-90 ({sup 90}Y) radioembolization represents an emerging transcatheter treatment option for the management of hepatocellular carcinoma (HCC). Elevation of the hepatopulmonary shunt fraction risks nontarget radiation to the lungs and may limit the use of {sup 90}Y therapy in patients with locally advanced disease with vascular invasion, who often demonstrate increased shunting. We present two cases in which patients with HCC and portal vein invasion resulting in elevated hepatopulmonary shunt fractions underwent chemoembolic shunt closure to allow safe {sup 90}Y radioembolization. Both patients demonstrated excellent tumor response and patient survival. On this basis, we propose a role for chemoembolic reduction of the lung shunt fraction before {sup 90}Y radioembolization in patients with extensive tumor-related hepatopulmonary shunting.

  18. Valved or valveless ventriculoperitoneal shunting in the treatment of post-haemorrhagic hydrocephalus

    DEFF Research Database (Denmark)

    Andreasen, Trine Hjorslev; Holst, Anders Vedel; Jørgensen, Alexander Lilja

    2016-01-01

    BACKGROUND: Implant infection and obstruction are major complications for ventriculoperitoneal shunts in patients with post-haemorrhagic hydrocephalus. In an effort to (1) reduce the incidence of these complications, (2) reduce the rate of shunt failure and (3) shorten the duration of neurosurgical...... hospitalisation, we have implemented valveless ventriculoperitoneal shunts at our department for adult patients with post-haemorrhagic hydrocephalus and haemorrhagic cerebrospinal fluid at the time of shunt insertion. METHODS: All adult patients (>18 years old) treated for post-haemorrhagic hydrocephalus.......3 %, p = 0.02), but a higher rate of overdrainage (10.3 % vs 2.6 %, p = 0.04). CONCLUSION: The use of a valveless shunting for patients with post-haemorrhagic hydrocephalus results in shorter duration of neurosurgical hospitalisation and lower rate of shunt infection, although these advantages should...

  19. A new shunt DC active filter of power supply in a steady high magnetic field facility

    Institute of Scientific and Technical Information of China (English)

    WANG Lei; LIU Xiao-Ning; WANG Can

    2011-01-01

    A DC active power filter is an indispensable part in a high power and high stability power supply system, especially in the power supply system of the Steady High Magnetic Field Facility, which requires that the current ripple should be limited to 50 parts per million. In view of the disadvantages of the series DC active power filter and shunt Pulse Width Modulation DC active filter, this paper puts forward a novel DC active filter by combining the advantages of the transistor regulator and the shunt type. The structure and principle of the new shunt linear active filter are introduced. Meanwhile, the design of several key components that construct the new shunt linear active filter is also analyzed. The simulation model and an experimental prototype of the shunt linear active filter are developed, and the results verify that the parameter design is reasonable and the shunt active filter has a good filter effect.

  20. Laparoscopic assisted ventriculoperitoneal shunt revisions as an option for pediatric patients with previous intraabdominal complications

    Directory of Open Access Journals (Sweden)

    Fernanda O. de Carvalho

    2014-04-01

    Full Text Available Multiple shunt failure is a challenge in pediatric neurosurgery practice and one of the most feared complications of hydrocephalus. Objective: To demonstrate that laparoscopic procedures for distal ventriculoperitoneal shunt failure may be an effective option for patients who underwent multiple revisions due to repetitive manipulation of the peritoneal cavity, abdominal pseudocyst, peritonitis or other situations leading to a “non reliable” peritoneum. Method: From March 2012 to February 2013, the authors reviewed retrospectively the charts of six patients born and followed up at our institution, which presented with previous intra-peritoneal complications and underwent ventriculoperitoneal shunt revision assisted by video laparoscopy. Results: After a mean follow-up period of nine months, all patients are well and no further shunt failure was identified so far. Conclusion: Laparoscopy assisted shunt revision in children may be, in selected cases, an effective option for patients with multiple peritoneal complications due to ventriculo-peritoneal shunting.

  1. Gold shunt for refractory advanced low-tension glaucoma with spared central acuity

    Directory of Open Access Journals (Sweden)

    Le R

    2016-03-01

    Full Text Available Ryan Le,1 Neeru Gupta1–3 1Keenan Research Center, Li Ka Shing Knowledge Institute, St. Michael’s Hospital, Toronto, ON, Canada; 2Ophthalmology and Vision Sciences, Glaucoma Unit, St. Michael’s Hospital, University of Toronto, Toronto, ON, Canada; 3Laboratory Medicine and Pathobiology, St. Michael's Hospital, University of Toronto, Toronto, ON, CanadaAbstract: The aim of this study is to report a case of gold shunt surgery for uncontrolled, low-tension glaucoma with good central vision, after having a previously failed trabeculectomy and tube shunt surgeries. The patient was receiving maximum medical glaucoma therapy of four different types with intraocular pressure of 17 mm Hg prior to gold shunt surgery. Five years later, intraocular pressure is well controlled in the low teens without the need for ocular medications, and glaucoma is stable following gold shunt surgery.Keywords: gold shunt, refractory glaucoma, glaucoma surgery, trabeculectomy, suprachoroidal space, tube shunt

  2. A multi-stack simulation of shunt currents in vanadium redox flow batteries

    Science.gov (United States)

    Wandschneider, F. T.; Röhm, S.; Fischer, P.; Pinkwart, K.; Tübke, J.; Nirschl, H.

    2014-09-01

    A model for the shunt currents in an all-vanadium redox flow battery consisting of 3 stacks which are electrically connected in series. It is based on an equivalent circuit which treats the shunt current pathways as Ohmic resistors. The conductivity of the vanadium electrolyte has been measured for different state-of-charges in order to implement a dependency of the resistances on the state-of-charge of the system. Published results are used to validate the simulation data of a single stack. Three setups of pipe networks are evaluated using the model. The pipe connections between the stacks give rise to external shunt currents, which also increase the amount of shunt currents within the stacks. These connections also lead to a nonuniform distribution of the shunt currents. The effects of the shunt currents on the Coulombic efficiency and the energy efficiency of the system are studied by the means of the model.

  3. Micro-surgical endodontics.

    Science.gov (United States)

    Eliyas, S; Vere, J; Ali, Z; Harris, I

    2014-02-01

    Non-surgical endodontic retreatment is the treatment of choice for endodontically treated teeth with recurrent or residual disease in the majority of cases. In some cases, surgical endodontic treatment is indicated. Successful micro-surgical endodontic treatment depends on the accuracy of diagnosis, appropriate case selection, the quality of the surgical skills, and the application of the most appropriate haemostatic agents and biomaterials. This article describes the armamentarium and technical procedures involved in performing micro-surgical endodontics to a high standard.

  4. Surgical innovation as sui generis surgical research.

    Science.gov (United States)

    Lotz, Mianna

    2013-12-01

    Successful innovative 'leaps' in surgical technique have the potential to contribute exponentially to surgical advancement, and thereby to improved health outcomes for patients. Such innovative leaps often occur relatively spontaneously, without substantial forethought, planning, or preparation. This feature of surgical innovation raises special challenges for ensuring sufficient evaluation and regulatory oversight of new interventions that have not been the subject of controlled investigatory exploration and review. It is this feature in particular that makes early-stage surgical innovation especially resistant to classification as 'research', with all of the attendant methodological and ethical obligations--of planning, regulation, monitoring, reporting, and publication--associated with such a classification. This paper proposes conceptual and ethical grounds for a restricted definition according to which innovation in surgical technique is classified as a form of sui generis surgical 'research', where the explicit goal of adopting such a definition is to bring about needed improvements in knowledge transfer and thereby benefit current and future patients.

  5. [Results of the surgical treatment of acute thrombosis of the major arteries of the limbs].

    Science.gov (United States)

    Ovchinnikov, V A; Vereshchagin, N A; Shavin, V V; Parakhoniak, N V

    1984-08-01

    An analysis of the surgical treatment of acute arterial trombosis of the extremities in 86 patients is presented. The causes of thrombosis were mainly obliterating atherosclerosis, artery trauma and postembolic occlusion. Best results of reconstructive operations were obtained in patients with postembolic occlusion of the arteries and their posttraumatic trombosis, worst results - in obliterating atherosclerosis. Thrombendarterectomy and autovenous shunts and prostheses were found to be the mos effective reconstructive operations.

  6. Transjugular intrahepatic portosystemic shunt combined with esophagogastric variceal embolization in the treatment of a large gastrorenal shunt

    Institute of Scientific and Technical Information of China (English)

    Qin; Jiang; Ming-Quan; Wang; Guo-Bing; Zhang; Qiong; Wu; Jian-Ming; Xu; De-Run; Kong

    2016-01-01

    AIM: To evaluate the efficacy and safety of transjugular intrahepatic portosystemic shunt(TIPS) combined with stomach and esophageal variceal embolization(SEVE) in cirrhotic patients with a large gastrorenal vessel shunt(GRVS).METHODS: Eighty-one cirrhotic patients with gastric variceal bleeding(GVB) associated with a GRVS were enrolled in the study and accepted TIPS combined with SEVE(TIPS + SEVE), by which portosystemic pressuregradient(PPG), biochemical, TIPS-related complications, shunt dysfunction, rebleeding, and death were evaluated. RESULTS: The PPGs before TIPS were greater than 12 mmH g in 81 patients. TIPS + SEVE treatment caused a significant decrease in PPG(from 37.97 ± 6.36 mmH g to 28.15 ± 6.52 mm Hg, t = 19.22, P < 0.001). The percentage of reduction in PPG was greater than 20%from baseline. There were no significant differences in albumin, alanine aminotransferase, aspartate aminotransferase, bilirubin, prothrombin time, or Child-Pugh score before and after operation. In all patients, rebleeding rates were 3%, 6%, 12%, 18%, and 18% at 1,3, 6, 12, and 18 mo, respectively. Five patients(6.2%)were diagnosed as having hepatic encephalopathy. The rates of shunt dysfunction were 0%, 4%, 9%, 26%,and 26%, at 1, 3, 6, 12, and 18 mo, respectively. The cumulative survival rates in 1, 3, 6, 12, and 18 mo were100%, 100%, 95%, 90%, and 90%, respectively.CONCLUSION: Our preliminary results indicated that the efficacy and safety of TIPS + SEVE were satisfactory in cirrhotic patients with GVB associated with a GRVS(GVB + GRVS).

  7. Capillary malformation--arteriovenous malformation syndrome: review of the literature, proposed diagnostic criteria, and recommendations for management.

    Science.gov (United States)

    Orme, Charisse M; Boyden, Lynn M; Choate, Keith A; Antaya, Richard J; King, Brett A

    2013-01-01

    Capillary malformation-arteriovenous malformation syndrome is an autosomal dominant disorder caused by mutations in the RASA1 gene and characterized by multiple small, round to oval capillary malformations with or without arteriovenous malformations. Ateriovenous malformations occur in up to one-third of patients and may involve the brain and spine. Although making the diagnosis is straightforward in some patients, there are other patients for whom diagnostic criteria may be helpful in their evaluation. Here we review the literature regarding capillary malformation-arteriovenous malformation syndrome, propose diagnostic criteria, and discuss the care of patients with this condition.

  8. [Traumatic arteriovenous pial fistula masquerading as a carotid-cavernous fistula: an uncommon disorder with an unusual presentation].

    Science.gov (United States)

    Santos-Franco, Jorge Arturo; Lee, Angel; Nava-Salgado, Giovanna; Zenteno, Marco; Gómez-Villegas, Thamar; Dávila-Romero, Julio César

    2012-01-01

    Traumatic intracranial pial arteriovenous fistulae are infrequent lesions. Their cardinal signs have been related to mass effect and hemorrhage, but their clinical manifestations due to venous retrograde flow into ophthalmic veins has never been described. This phenomenon is usually seen in dural arteriovenous fistula draining to the cavernous sinus or carotid-cavernous sinus fistula.A traumatic intracranial pial arteriovenous fistula arising from the supraclinoid internal carotid artery in a young patient was revealed by aggressive behavior and ophthalmologic manifestations. The endovascular management included the use of coils, stent, and ethylene-vinyl alcohol with transient balloon occlusion of the parent vessel.

  9. Postoperative Residual Shunt After Repair of Ventricular Septal Defect Among Children%小儿室间隔缺损术后残余漏

    Institute of Scientific and Technical Information of China (English)

    蒋雄刚

    1995-01-01

    8例小儿室间隔缺损修补术后残余漏再次手术病例分析:残余漏表现为5例术后残留心前区Ⅲ级以上收缩期杂音,7例血红蛋白尿,2例右心衰,8例超声心动图(UCG)证实心室水平残余左向右分流.均于术后2~112天行残余漏修补.术中见残余漏原因为不同部位缝针处组织撕裂6例,修补不全2例.8例均经带垫片褥式缝合加固,7例痊愈,1例再次发生残余漏.本文对残余漏特点、诊断、手术适应证及时机进行了讨论.%Eight cases of postoperative residual shunt after repair of venticular septal defect (VSD) were analysed in this paper.Their clinical features disclosed:hemofiubinuria in 7 cases,cardiac murmur in 5 and residual shunt signs on echocardiograph in 8.In the operation for residual shunt,it was found:the tear in septal leaflet in aneurysm-like VSD in 2 cases,the tear in septal leaflet of tricuspid in 4,infundibular muscular 2 and residual triangle defect under the patch repair in VSD 2.Residual shunt in all the 8 cases were repaired with mattress suture under cardiopulmonary bypass,seven patients recovered without hemogiobinuria or cardiac murmur,but one had residual shunt again and cerebral insufficiency,which was improved by medical therapy.The harmfulness,the diagnosis and prevention of postoperative residual shunt,the operative indication,optimal time and surgical procedures were discussed.

  10. An intratesticular arteriovenous malformation identified incidentally during ultrasound evaluation of scrotal trauma

    Directory of Open Access Journals (Sweden)

    Mohammad Saleh Jafarpishefard

    2016-01-01

    Full Text Available Intratesticular arteriovenous malformation (AVM is an extremely rare benign testicular lesion. Ultrasonography (US usually reveals a hypoechoic solid vascular mass within the testicular parenchyma. Herein, we report our experience with a young patient in whom an intratesticular AVM was found incidentally by US during the workup of scrotal trauma.

  11. Novel cases of amyotrophic lateral sclerosis after treatment of cerebral arteriovenous malformationss.

    Science.gov (United States)

    Linnebank, Michael; McDougall, Cameron G; Krueger, Stefanie; Biskup, Saskia; Neumann, Manuela; Weller, Michael; Valavanis, Antonios; Prudlo, Johannes

    2016-01-01

    Previous case studies reported nine patients with cerebral arteriovenous malformations (AVM) who developed amyotrophic lateral sclerosis (ALS) after AVM embolisation. Here, we describe three novel cases of ALS which developed 13-34 years after treatment, including embolisation, of cerebral AVM. This study provides further arguments supporting the thesis that embolisation of cerebral AVM might influence the risk of later ALS development.

  12. Prefabrication of axial vascularized tissue engineering coral bone by an arteriovenous loop: A better model

    Energy Technology Data Exchange (ETDEWEB)

    Dong Qingshan [Department of Oral and Maxillofacial Surgery, Wuhan General Hospital of Guangzhou Military Command, Wuhan 430070 (China); Shang Hongtao; Wu Wei [Department of Oral and Maxillofacial Surgery, School of Stomatology, Fourth Military Medical University, Xi' an 710032 (China); Chen Fulin [Lab of Tissue Engineering, Faculty of Life Science, Northwest University, Xi' an 710069 (China); Zhang Junrui [Department of Oral and Maxillofacial Surgery, School of Stomatology, Fourth Military Medical University, Xi' an 710032 (China); Guo Jiaping [Department of Oral and Maxillofacial Surgery, Wuhan General Hospital of Guangzhou Military Command, Wuhan 430070 (China); Mao Tianqiu, E-mail: tianqiumao@126.com [Department of Oral and Maxillofacial Surgery, School of Stomatology, Fourth Military Medical University, Xi' an 710032 (China)

    2012-08-01

    The most important problem for the survival of thick 3-dimensional tissues is the lack of vascularization in the context of bone tissue engineering. In this study, a modified arteriovenous loop (AVL) was developed to prefabricate an axial vascularized tissue engineering coral bone in rabbit, with comparison of the arteriovenous bundle (AVB) model. An arteriovenous fistula between rabbit femoral artery and vein was anastomosed to form an AVL. It was placed in a circular side groove of the coral block. The complex was wrapped with an expanded-polytetrafluoroethylene membrane and implanted beneath inguinal skin. After 2, 4, 6 and 8 weeks, the degree of vascularization was evaluated by India ink perfusion, histological examination, vascular casts, and scanning electron microscopy images of vascular endangium. Newly formed fibrous tissues and vasculature extended over the surfaces and invaded the interspaces of entire coral block. The new blood vessels robustly sprouted from the AVL. Those invaginated cavities in the vascular endangium from scanning electron microscopy indicated vessel's sprouted pores. Above indexes in AVL model are all superior to that in AVB model, indicating that the modified AVL model could more effectively develop vascularization in larger tissue engineering bone. - Highlights: Black-Right-Pointing-Pointer A modified arteriovenous loop (AVL) model in rabbit was developed in this study. Black-Right-Pointing-Pointer Axial prevascularization was induced in a larger coral block by using the AVL. Black-Right-Pointing-Pointer The prefabrication of axial vascularized coral bone is superior as vascular carrier.

  13. Quality of life, anxiety, and depression in patients with an untreated intracranial aneurysm or arteriovenous malformation

    NARCIS (Netherlands)

    van der Schaaf, IC; Brilstra, EH; Rinkel, GJE; Bossuyt, PM; van Gijn, J

    2002-01-01

    Background and Purpose-The objective of this study was to assess the health-related quality of life and symptoms of anxiety and depression in patients who are aware of the presence of a patent aneurysm or arteriovenous malformation. Methods-Participants were retrospectively identified and invited to

  14. Neuro-endovascular Embolic Agent for Treatment of a Renal Arteriovenous Fistula

    Directory of Open Access Journals (Sweden)

    Gurpreet Singh

    2016-01-01

    Full Text Available Renal arteriovenous fistula is a known complication following a renal biopsy, and may require catheter based embolization. Distal location of these fistulas in the renal parenchyma in many a case may necessitate non-traditional embolic materials. Liquid embolic agents that allow a controlled delivery may be suitable in this situation, as demonstrated in this case report.

  15. Arteriovenous Malformation in Temporal Lobe Presenting as Contralateral Ocular Symptoms Mimicking Carotid-Cavernous Fistula

    Directory of Open Access Journals (Sweden)

    Fadzillah Mohd-Tahir

    2013-01-01

    Full Text Available Aim. To report a rare case of arteriovenous malformation in temporal lobe presenting as contralateral orbital symptoms mimicking carotid-cavernous fistula. Method. Interventional case report. Results. A 31-year-old Malay gentleman presented with 2-month history of painful progressive exophthalmos of his left eye associated with recurrent headache, diplopia, and reduced vision. Ocular examination revealed congestive nonpulsating 7 mm exophthalmos of the left eye with no restriction of movements in all direction. There was diplopia in left lateral gaze. Left IOP was elevated at 29 mmHg. Left eye retinal vessels were slightly dilated and tortuous. CT scan was performed and showed right temporal arteriovenous malformation with a nidus of 3.8 cm × 2.5 cm with right middle cerebral artery as feeding artery. There was dilated left superior ophthalmic vein of 0.9 mm in diameter with enlarged left cavernous sinus. MRA and carotid angiogram confirmed right temporal arteriovenous malformation with no carotid-cavernous fistula. Most of the intracranial drainage was via left cavernous sinus. His signs and symptoms dramatically improved following successful embolisation, completely resolved after one year. Conclusion. Intracranial arteriovenous malformation is rarely presented with primary ocular presentation. Early intervention would salvage the eyes and prevent patients from more disaster morbidity or fatality commonly due to intracranial haemorrhage.

  16. Paradoxical embolism following thromboaspiration of an arteriovenous fistula thrombosis: a case report

    Directory of Open Access Journals (Sweden)

    Amara Brahim

    2010-10-01

    Full Text Available Abstract Introduction Paradoxical embolism is an increasingly reported cause of arterial embolism. Several embolic sources have been described, but thrombosis of an arteriovenous fistula as a paradoxical emboligenic source has not, to the best of our knowledge, been reported. Case presentation A 50-year-old Caucasian woman received a renal graft for primary hyperoxaluria. After transplantation, she was maintained on daily hemodialysis. Thrombosis of her arteriovenous fistula occurred two weeks post-transplantation and was treated by thromboaspiration, which was partially successful. During a hemodialysis session immediately following thromboaspiration, she developed a coma with tetraplegia requiring intensive cardiorespiratory resuscitation. Brain magnetic resonance imaging revealed various hyperdense areas in the vertebrobasilar territory resulting from bilateral occlusion of posterior cerebral arteries. Transesophageal echocardiographic examination showed a patent foramen ovale, while pulse echography of the arteriovenous fistula revealed the persistence of extensive clots that were probably the embolic source. A paradoxical embolus through a patent foramen ovale was suggested because of the proximity of the neurological event to the thrombectomy procedure. Conclusions The risk of paradoxical embolism in a hemodialyzed patient with a patent foramen ovale deserves consideration and requires careful evaluation in situations of arteriovenous fistula thrombosis.

  17. Acquired Chiari malformation type I associated with a supratentorial fistulous arteriovenous malformation: a case report.

    Science.gov (United States)

    Chen, Kuo-Wei; Kuo, Meng-Fai; Lee, Chung-Wei; Tu, Yong-Kwang

    2015-03-01

    A case of acquired Chiari malformation type I with frontal fistulous arteriovenous malformation (AVM) is presented, and the pathophysiology is discussed. The tonsillar herniation and hydrocephalus both resolved after AVM was excised. This case provides some insight into the complex hemodynamic change exerted by the fistulous AVM and the mechanism of the development of acquired Chiari malformation type I.

  18. The value of baseline CT head scans in the assessment of shunt complications in hydrocephalus

    Energy Technology Data Exchange (ETDEWEB)

    Cantrell, P. (Alder Hey Children' s Hospital, Liverpool (United Kingdom)); Fraser, F. (Alder Hey Children' s Hospital, Liverpool (United Kingdom)); Pilling, D. (Alder Hey Children' s Hospital, Liverpool (United Kingdom)); Carty, H. (Alder Hey Children' s Hospital, Liverpool (United Kingdom))

    1993-10-01

    The purpose of this study was to determine the value of a baseline CT head scan in the assessment of patients who subsequently presented with symptoms which may have been due to shunt complications (such as blockage or infection). In all these patients the shunt had been inserted in the treatment of hydrocephalus. We conclude that the presence of a baseline scan does not add to the interpretation of CT scans done when the patient presents with symptoms of possible shunt malfunction. (orig.)

  19. Evaluation of Magnetostrictive Shunt Damper Performance Using Iron (Fe)-Gallium (Ga) Alloy

    Science.gov (United States)

    2013-09-01

    Evaluation of Magnetostrictive Shunt Damper Performance Using Iron (Fe)-Gallium (Ga) Alloy by Andrew James Murray and Dr. JinHyeong Yoo...Aberdeen Proving Ground, MD 21005 ARL-TN-0566 September 2013 Evaluation of Magnetostrictive Shunt Damper Performance Using Iron (Fe... Magnetostrictive Shunt Damper Performance Using Iron (Fe)- Gallium (Ga) Alloy 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6

  20. Partial portacaval shunt with H-grafts to treat portal hypertension

    Institute of Scientific and Technical Information of China (English)

    XU Geliang; HU Hejie; LI Jiansheng; YANG Shugao; CHAI Zhongpei; XU Rongnan

    2007-01-01

    Partial portosystemic shunts have been popularized because of a reported low rate of mortality and morbidity (especially encephalopathy,liver failure and occlusion).The results of partial portacaval shunts[small-diameter expanded polytetrafluoroethylene(ePTFE)H-graft portacaval shunt]were retrospectively reviewed to evaluate the clinical efficacy in the treatment of portal hypertension.Forty-three patients with portal hypertension were treated by small-diameter H-graft of ePTFE portacaval shunt from May 1995 to April 2006.Thirty-three had externally ringed grafts and ten had non-ringed ones.Ten had grafts of 10mm in diameter and 33 had grafts of 8 mm.The left gastric artery and coronary vein were ligated in all the cases.Six had pericardial devascularization and splenectomy was performed in 42.An average decrease of flee portal pressure(FPP)from(33.24±4.78)cm H2O before shunting and(13.65±5.65)cmH2O after shunting was observed.The portal blood flow was reduced by one-third of that before shunt.Thirty-eight patients survived and no upper gastro-intestinal rebleeding occurred in the follow-up period(50.5 months in average).Two were out of contact.Color Doppler ultrasonography and/or portography revealed the shunts were Patent in 38 cases and were occluded in three cases(3/41,7.3%).Encephalopathy developed in five cases(5/41,12.2%).Partial(small-diameter ePTFE H-graft)portacaval shunting Can reduce the portal pressure effectively.Majority of the hepatic flow from the portal vein can be maintained adequately.The shunts with reinforced grafts can keep a higher rate of patency.The morbidity of encephalopathy was lower than those with total shunt.The partial portacaval shunt is effective in preventing recurrent variceal bleeding.

  1. Small-diameter prosthetic H-graft portacaval shunts in the treatment of portal hypertension

    Institute of Scientific and Technical Information of China (English)

    胡何节; 许戈良; 李建生; 杨树高; 柴仲培; 徐荣楠

    2004-01-01

    Background Portasystemic shunts, especially total shunts, are effective tools for reducing portal pressure and controlling variceal bleeding but lead to high risk of encephalopathy and accelerating liver ailure. The purpose of this study is to evaluate the clinical effects of small-diameter expanded polytetrafluoroethylene (ePTFE) H-graft portacaval shunts in the treatment of portal hypertension. Methods Thirty-one patients with portal hypertension were treated with ePTFE small-diameter H-graft portacaval shunts from December 1995 to April 2002. Twenty-one had externally ringed grafts and 10 had non-ringed grafts; 20 had 10 mm diameter grafts and 11 had 8 mm grafts. The left gastric artery and coronary vein were ligated in 22 patients. Additionally, 6 patients underwent pericardial devascularization, and splenectomies were performed on 30 patients. Results An average decrease of free portal pressure (FPP) from (32.13 ~4.86) cmH2O before shunting to (12.55±5. 57) cmH2O after shunting was observed. Portal blood flow was reduced by 1/3 compared with the levels measured before shunting. Twenty-eight patients survived after the operation, and no upper gastrointestinal rebleeding occurred in the follow-up period (40.2 months on average). We lost contact with one patient. Color Doppler ultrasonography and/or portography revealed the shunts to be patent in 28 cases and occluded in 2 (6.4% ) cases. Encephalopathy developed in 4 patients (12.9%). Conclusion Small-diameter ePTFE H-graft portacaval shunts can effectively reduce portal pressure. Moreover, the majority of the hepatopetal flow from the portal vein can be adequately maintained. The reinforced shunts may achieve a higher rate of patency. Morbidity from encephalopathy was less frequent than in pateints receiving total shunts. Small-diameter H-graft portacaval shunts are also effective in preventing recurrent variceal bleeding.

  2. Focal Sparing of the Fatty Liver Caused by a Nontumorous Arterioportal Shunt

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Min Woo; Kim, Young Jun; Jeon, Hae Jeong; Lee, Nam Ju; Moon, Sung Gyu; Yi, Jeong Geun [Konkuk University Hospital, Seoul (Korea, Republic of)

    2007-06-15

    We present two cases of focal fatty sparing caused by a nontumorous arterioportal shunt. Two patients underwent ultrasonography (US) as a part of routine medical screening, which revealed a hypoechoic lesion in the diffuse fatty liver. Each lesion appeared to be an arterioportal shunt on triphasic mutidetector computed tomography (CT) and was seen as being slightly hyperdense on noncontrast CT. No tumors were delineated around or within the arterioportal shunt. Both lesions remained unchanged on six-month follow-up US

  3. Ultrasonic Contrast Portography for Demonstration of Intrahepatic Porto-systemic Shunts

    Directory of Open Access Journals (Sweden)

    Yi-Hong Chou

    2016-03-01

    Full Text Available Spontaneous intrahepatic porto-systemic shunts (IHPSS can be disclosed with ultrasound (US and color Doppler ultrasound (CDU. However, direct evidence of the shunt on US or CDU may not be convincing. In this report we demonstrate the presence of IHPSS by ultrasonic contrast portography with intravenous injection of microbubble-based contrast agent (MBCA. With this technique, the MBCA was depicted to enter the hepatic vein through the shunt, and then flowed into the inferior vena cava.

  4. High-accuracy current measurement with low-cost shunts by means of dynamic error correction

    OpenAIRE

    Weßkamp, Patrick; Melbert, Joachim

    2016-01-01

    Measurement of electrical current is often performed by using shunt resistors. Thermal effects due to self-heating and ambient temperature variation limit the achievable accuracy, especially if low-cost shunt resistors with increased temperature coefficients are utilized. In this work, a compensation method is presented which takes static and dynamic temperature drift effects into account and provides a significant reduction of measurement error. A thermal model of the shunt...

  5. The Arteriovenous Difference in Hemostatic Parameters in Critically Ill Patients with Different Types of Energy Deficiency

    Directory of Open Access Journals (Sweden)

    I. B Zabolotskikh

    2013-01-01

    Full Text Available Objective: to reveal the patterns of hemostatic disorder development in the venous and arterial bed in relation to the type of energy deficiency. Subjects and methods. One hundred and ninety-nine patients who had undergone extensive abdominal surgeries (gastrectomy, pancreatoduodenectomies, hemicolectomies, hepatectomies, etc. were examined. Among the patients, there were 5 groups: a control group without energy deficiency and 4 groups of patients who were recorded to have one of the types of energy deficiency: substrate, hypermetabolic, hypoxic, and enzymatic. Results and discussion. The nature and degree of existing metabolic disturbances and changes in the arteriovenous difference in hemostasiological parameters have a statistically proven relationship (on the basis of ROC analysis. Substrate energy deficiency was characterized by the insignificant changes in the hemostatic system as a whole, which affect only its coagulation component; the arteriovenous difference in hemostasiological parameters was similar to that in the patients without energy deficiency. In hypermetabolic energy deficiency, the venous bed demonstrated the most pronounced hemostatic changes (hypercoagulation, suppressed fibrinolysis, and enhanced platelet aggregation. The hemostatic changes that were more significant than those in the above group were responsible for the formation of a significant arteriovenous difference in the hemostasiological parameters; however, the direction of this difference did not differ from that in the patients without energy deficiency. In hypoxic energy deficiency, hemostatic disorders were heterodirectional in the arterial and venous bed (these were most marked in the arterial bed — hypercoagulation, activated fibrinolysis, and enhanced platelet aggregation therefore there was a significant arteriovenous difference in the hemostasiological parameters, which was opposite as compared to that in the patients without energy deficiency. In

  6. Robert H. Pudenz (1911-1998) and Ventriculoatrial Shunt: Historical Perspective.

    Science.gov (United States)

    Konar, Subhas K; Maiti, Tanmoy K; Bir, Shyamal C; Kalakoti, Piyush; Nanda, Anil

    2015-11-01

    Robert H. Pudenz was a renowned neurosurgeon in North America in the 20th century, famous for his contributions in the evolution of the shunt valve and ventriculoatrial shunt surgery. With his innovative idea and help from Heyer, in 1955, he demonstrated that a venous catheter worked best when in the right atrium and that the slit valve should be located at the most distal portion of the shunt system to prevent retrograde filling and thrombosis. He also contributed to various experimental studies on the brain, especially the electrical response of different neural structures. This historical vignette focuses on the work of Robert Pudenz and the evolution of the ventriculoatrial shunt.

  7. Biofilm-associated infection: the hidden face of cerebrospinal fluid shunt malfunction.

    Science.gov (United States)

    Mounier, Roman; Kapandji, Natacha; Birnbaum, Ron; Cook, Fabrice; Rodriguez, Cristophe; Nebbad, Bibba; Lobo, David; Dhonneur, Gilles

    2016-12-01

    Diagnosis of cerebrospinal fluid (CSF) shunt infection is difficult. Growing evidence links this pattern to biofilm-associated infections (BAI). Biofilm may explain the indolent development of the infection, and the poor efficiency of traditional microbiologic methods. We report the case of a patient admitted for hydrocephalus associated to CSF shunt malfunction. None of the clinical, serum, or CSF laboratory findings were in favor of an infectious process. Only scanning electron microscopy (SEM) revealed the presence of biofilm. Hence, despite a broad CSF shunt infection definition, some infections could remain undiagnosed by the traditional approach. This study is the first to provide some direct evidence for bacterial biofilm-associated CSF shunt infection.

  8. Intrahepatic porto-hepatic venous shunts in Rendu-Osler-Weber disease: imaging demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Shunro; Mori, Hiromu; Yamada, Yasunari; Hayashida, Tomoko; Hori, Yuzo; Kiyosue, Hiro [Department of Radiology, Oita Medical University, Idaigaoka 1-1, Hasama-machi, 879-5593, Oita (Japan)

    2004-04-01

    This study describes the imaging features of the intrahepatic portohepatic venous (PHV) shunt, which is a potential cause of portosystemic encephalopathy in Rendu-Osler-Weber disease. Six patients with Rendu-Osler-Weber disease (two men, four women; age range 42-73 years) were retrospectively studied. There were two from one family and three from another family. Of these patients, one was diagnosed with definitive portosystemic encephalopathy because of a psychiatric disorder. We retrospectively reviewed the radiological examinations, including abdominal angiography (n=6), three-phase dynamic helical computed tomography (CT; n=3), and conventional enhanced CT (n=1). In one patient, CT during angiography and CT angioportography were also performed. Evaluation was placed on the imaging features of intrahepatic PHV shunts. On angiography, intrahepatic PHV shunts showing multiple and small shunts <5 mm in diameter in an apparent network were detected in all patents. In two patients, a large shunt with a size of either 7 or 10 mm was associated. These intrahepatic PHV shunts were predominantly distributed in the peripheral parenchyma. Intrahepatic PHV shunts would be characterized by small and multiple shunts in an apparent network on the periphery with or without a large shunt. (orig.)

  9. [Giant cervical angioma caused by "malignant" arteriovenous fistulae].

    Science.gov (United States)

    Palou, J; Mir y Mir, L

    1992-01-01

    A case of angioma by malignant AV fistula (described by F. Martorell in 1970) is reported. Such kind of fistulas have usually a lethal course. The case reported underwent a surgical correction, and after a following of 10 years, no major complications have been reported.

  10. Clinical consequences of infected arteriovenous grafts in hemodialysis patients.

    Science.gov (United States)

    Minga, T E; Flanagan, K H; Allon, M

    2001-11-01

    Arteriovenous (AV) graft infection is a serious adverse event in hemodialysis patients; however, there is little published literature describing its consequences. We identified prospectively all AV graft infections occurring at our institution during a 4.5-year period. We analyzed immediate complications, as well as long-term consequences, including the need for subsequent vascular-access procedures and duration of catheter-dependent dialysis therapy. Ninety graft infections were identified in 78 patients, yielding a rate of 8.2 infections/100 graft-years. Patients with graft infection were much more likely to have a low serum albumin level (<3.5 g/dL) in the month preceding the infection compared with noninfected controls (73% versus 18%; P < 0.001). Infections occurred within 1 month of graft placement in 15%, at 1 to 12 months in 44%, and longer than 1 year from surgery in 41%. The pathogen was a gram-positive coccus in 97% of cases, particularly Staphylococcus aureus (60%) and Staphylococcus epidermidis (22%). The initial graft infection entailed hospitalization for a mean of 7.5 days. Eleven patients (12%) developed a total of 17 major complications, including death (5 patients), clinical sepsis requiring vasopressors (4 patients), septic arthritis (3 patients), epidural abscess (1 patient), endocarditis (1 patient), osteomyelitis (1 patient), myocardial infarction (1 patient), and cerebrovascular accident (1 patient). After removal of an infected graft, patients were catheter dependent for a median of 3.8 months. The duration of catheter dependence was less than 3 months in 36%, 3 to 6 months in 38%, 6 to 12 months in 14%, and greater than 1 year in 12%. During the period of catheter dependence, patients required a mean of 9.7 access procedures, including graft removal (1.0 procedure), nontunneled dialysis catheters (4.4 procedures), tunneled dialysis catheters (3.0 procedures), and new permanent accesses (1.4 procedures). In addition, patients averaged 0

  11. Central arteriovenous anastomosis for the treatment of patients with uncontrolled hypertension (the ROX CONTROL HTN study): a randomised controlled trial.

    LENUS (Irish Health Repository)

    Lobo, Melvin D

    2015-01-22

    Hypertension contributes to cardiovascular morbidity and mortality. We assessed the safety and efficacy of a central iliac arteriovenous anastomosis to alter the mechanical arterial properties and reduce blood pressure in patients with uncontrolled hypertension.

  12. Imbalance of matrix metalloproteinase-9 and matrix metalloproteinase tissue inhibitor-1 may contribute to hemorrhage in cerebellar arteriovenous malformations

    Institute of Scientific and Technical Information of China (English)

    Fei Di; Tongyan Chen; Hongli Li; Jizong Zhao; Shuo Wang; Yuanli Zhao; Dong Zhang

    2012-01-01

    In this study,we determined the expression levels of matrix metalloproteinase-2 and -9 and matrix metalloproteinase tissue inhibitor-1 and -2 in brain tissues and blood plasma of patients undergoing surgery for cerebellar arteriovenous malformations or primary epilepsy (control group).Immunohistochemistry and enzyme-linked immunosorbent assay revealed that the expression of matrix metalloproteinase-9 and matrix metalloproteinase tissue inhibitor-1 was significantly higher in patients with cerebellar arteriovenous malformations than in patients with primary epilepsy.The ratio of matrix metalloproteinase-9 to matrix metalloproteinase tissue inhibitor-1 was significantly higher in patients with hemorrhagic cerebellar arteriovenous malformations compared with those with non-hemorrhagic malformations.Matrix metalloproteinase-2 and matrix metalloproteinase tissue inhibitor-2 levels were not significantly changed.These findings indicate that an imbalance of matrix metalloproteinase-9 and matrix metalloproteinase tissue inhibitor-1,resulting in a relative overabundance of matrix metalloproteinase-9,might be the underlying mechanism of hemorrhage of cerebellar arteriovenous malformations.

  13. Validated linear dynamic model of electrically-shunted magnetostrictive transducers with application to structural vibration control

    Science.gov (United States)

    Scheidler, Justin J.; Asnani, Vivake M.

    2017-03-01

    This paper presents a linear model of the fully-coupled electromechanical behavior of a generally-shunted magnetostrictive transducer. The impedance and admittance representations of the model are reported. The model is used to derive the effect of the shunt’s electrical impedance on the storage modulus and loss factor of the transducer without neglecting the inherent resistance of the transducer’s coil. The expressions are normalized and then shown to also represent generally-shunted piezoelectric materials that have a finite leakage resistance. The generalized expressions are simplified for three shunts: resistive, series resistive-capacitive, and inductive, which are considered for shunt damping, resonant shunt damping, and stiffness tuning, respectively. For each shunt, the storage modulus and loss factor are plotted for a wide range of the normalized parameters. Then, important trends and their impact on different applications are discussed. An experimental validation of the transducer model is presented for the case of resistive and resonant shunts. The model closely predicts the measured response for a variety of operating conditions. This paper also introduces a model for the dynamic compliance of a vibrating structure that is coupled to a magnetostrictive transducer for shunt damping and resonant shunt damping applications. This compliance is normalized and then shown to be analogous to that of a structure that is coupled to a piezoelectric material. The derived analogies allow for the observations and equations in the existing literature on structural vibration control using shunted piezoelectric materials to be directly applied to the case of shunted magnetostrictive transducers.

  14. Persistent hydrocephalus due to postural activation of a ventricular shunt anti-gravity device.

    Science.gov (United States)

    Craven, Claudia L; Toma, Ahmed K; Watkins, Laurence D

    2017-03-01

    The ever present need to balance over drainage with under drainage in hydrocephalus has required innovations including adjustable valves with antigravity devices. These are activated in the vertical position to prevent siphoning. We describe a group of bedridden patients who presented with unexplained under drainage caused by activation of antigravity shunt components produced by peculiar head/body position. Retrospective single centre case series of hydrocephalus patients, treated with ventriculo-peritoneal (VP) shunt insertion between April 2014 - February 2016. These patients presented with clinical and radiological under drainage syndrome. Medical notes were reviewed for clinical picture and outcome. Radiological studies were reviewed assessing shunt placement and ventricular size. Seven patients presented with clinical and radiological under drainage syndrome. A consistent posturing of long term hyper-flexion of the neck whilst lying supine was observed. All patients had similar shunt construct (adjustable Miethke ProGAV valve and shunt assistant anti-gravity component). In each of those patients a hypothesis was formulated that neck flexion was activating the shunt assistance anti-gravity component in supine position. Five patients underwent shunt revision surgery removing the shunt assistant device from the cranium and adding an anti-gravity component to the shunt system at the chest. One had the shunt assistant completely removed and one patient was managed conservatively with mobilisation. All patients had clinical and radiological improvement. Antigravity shunt components implanted cranially in bedridden hydrocephalus patients will produce underdrainage due to head flexion induced anti-gravity device activation. In these patients, anti-gravity devices should be placed at the chest. Alternatively, special nursing attention should be paid to head-trunk angle.

  15. Arterio-venous flow between monochorionic twins determined during intra-uterine transfusion. Nonlinear decay of adult red blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Gemert, Martin J C van; Wijngaard, Jeroen P H M van den [Laser Centre and Department of Obstetrics, Academic Medical Centre, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam (Netherlands); Pasman, Suzanne A; Vandenbussche, Frank P H A [Division of Fetal Medicine, Department of Obstetrics, Leiden University Medical Centre, Leiden (Netherlands); Lopriore, Enrico [Division of Neonatology, Department of Pediatrics, Leiden University Medical Centre, Leiden (Netherlands)], E-mail: m.j.vangemert@amc.uva.nl

    2008-07-07

    Recently, we derived equations relating the flow of adult red blood cells through a placental arterio-venous anastomosis with intra-uterine and post-natal measured adult hemoglobin concentrations. In this letter, we re-derived the equations, now including a more realistic nonlinear decay of adult red blood cells, and re-evaluated the measurement accuracy of the arterio-venous flow and the lifetime of the red blood cells. (letter to the editor)

  16. Atypical MRI features in soft-tissue arteriovenous malformation: a novel imaging appearance with radiologic-pathologic correlation

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Anand S. [University of California, San Francisco, Department of Radiology and Biomedical Imaging, San Francisco, CA (United States); University of California, San Francisco, Department of Interventional Radiology, San Francisco, CA (United States); Schulman, Joshua M.; Ruben, Beth S. [University of California, San Francisco, Departments of Pathology and Dermatology, San Francisco, CA (United States); Hoffman, William Y. [University of California, San Francisco, Department of Plastic Surgery, Birthmarks and Vascular Anomalies Clinic, San Francisco, CA (United States); Dowd, Christopher F. [University of California, San Francisco, Department of Interventional Neuroradiology, Birthmarks and Vascular Anomalies Clinic, San Francisco, CA (United States); Frieden, Ilona J. [University of California, San Francisco, Department of Dermatology, Birthmarks and Vascular Anomalies Clinic, San Francisco, CA (United States); Hess, Christopher P. [University of California, San Francisco, Department of Neuroradiology, Birthmarks and Vascular Anomalies Clinic, San Francisco, CA (United States)

    2015-09-15

    The absence of a discrete mass, surrounding signal abnormality and solid enhancement are imaging features that have traditionally been used to differentiate soft-tissue arteriovenous malformations from vascular tumors on MRI. We have observed that these findings are not uncommon in arteriovenous malformations, which may lead to misdiagnosis or inappropriate treatment. To estimate the frequency of atypical MRI features in soft-tissue arteriovenous malformations and assess their relationship to lesion size, location, tissue type involved and vascular architecture. Medical records, MRI and histopathology were reviewed in consecutive patients with soft-tissue arteriovenous malformations in a multidisciplinary vascular anomalies clinic. Arteriovenous malformations were divided into those with and without atypical MRI findings (perilesional T2 signal abnormality, enhancement and/or a soft-tissue mass). Lesion location, size, tissue involved and vascular architecture were also compared between groups. Tissue stains were reviewed in available biopsy or resection specimens to assess relationships between MRI findings and histopathology. Thirty patients with treatment-naive arteriovenous malformations were included. Fifteen lesions demonstrated atypical MRI. There was no difference in age, gender, lesion size or involved body part between the groups. However, more than half of the atypical lesions demonstrated multicompartmental involvement, and tiny intralesional flow voids were more common in atypical arteriovenous malformations. Histopathology also differed in atypical cases, showing densely packed endothelial cells with connective tissue architectural distortion and edema. Arteriovenous malformations may exhibit features of a vascular tumor on MRI, particularly when multicompartmental and/or containing tiny internal vessels. These features are important to consider in suspected fast-flow vascular malformations and may have implications with respect to their treatment

  17. Hernia Surgical Mesh Implants

    Science.gov (United States)

    ... Prosthetics Hernia Surgical Mesh Implants Hernia Surgical Mesh Implants Share Tweet Linkedin Pin it More sharing options ... majority of tissue used to produce these mesh implants are from a pig (porcine) or cow (bovine) ...

  18. Urogynecologic Surgical Mesh Implants

    Science.gov (United States)

    ... Prosthetics Urogynecologic Surgical Mesh Implants Urogynecologic Surgical Mesh Implants Share Tweet Linkedin Pin it More sharing options ... majority of tissue used to produce these mesh implants are from a pig (porcine) or cow (bovine). ...

  19. Abortion - surgical - aftercare

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000658.htm Abortion - surgical - aftercare To use the sharing features on ... please enable JavaScript. You have had a surgical abortion. This is a procedure that ends pregnancy by ...

  20. Characteristics of shunting arc discharge for carbon ion source

    Science.gov (United States)

    Takaki, K.; Mukaigawa, S.; Fujiwara, T.; Kumagai, M.; Yukimura, K.

    2003-05-01

    The criteria of initial resistance of carbon rod for shunting arc ignition are described in this article. The five different resistances were used. The rods are 40 mm in length and 2 mm in diameter. The carbon rod was set in the vacuum and was initially heated up with a pulsed current supplied by a charged capacitor with a capacitance of 20 μF, followed by a self-ignition. The heating energy is almost independent of the charging voltage of the capacitor. The heating energy increases with decreasing the rod resistance, whereas the energy deposited in the plasma and the utilizing efficiency of the charged energy in the capacitor decreases.