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Sample records for tomography ct bladder

  1. Computed Tomography (CT) -- Head

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    Full Text Available ... Professions Site Index A-Z Computed Tomography (CT) - Head Computed tomography (CT) of the head uses special ... the Head? What is CT Scanning of the Head? Computed tomography, more commonly known as a CT ...

  2. Computerized tomography of gall bladder cancer

    International Nuclear Information System (INIS)

    Todua, F.I.; Karmazanovskij, G.G.

    1989-01-01

    The authors have summed up the experience in the use of computerized tomography (CT) in diagnosis of gall bladder cancer. The investigation of 17 patients with cancer of this site showed a high informative value of the method. A retrospective comparative study of the results of CT and surgical interventions was carried out. It has been concluded that CT makes it possible not only to diagnose malignant lesions of the bile ducts but also to assess a possible scope of a forthcoming operation

  3. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... Videos About Us News Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Sinuses Computed tomography ( ... cross-sectional images generated during a CT scan can be reformatted in multiple planes, and can even ...

  4. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... the Sinuses? What is CT (Computed Tomography) of the Sinuses? Computed tomography, more commonly known as a ... of page What are some common uses of the procedure? CT of the sinuses is primarily used ...

  5. Computed Tomography (CT) -- Head

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    Full Text Available ... Perfusion of the Head CT Angiography (CTA) Stroke Brain Tumors Computer Tomography (CT) Safety During Pregnancy Head and Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to Computed Tomography (CT) - Head Videos related to Computed Tomography ( ...

  6. Computed Tomography (CT) -- Head

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    Full Text Available ... the limitations of CT Scanning of the Head? What is CT Scanning of the Head? Computed tomography, ... than regular radiographs (x-rays). top of page What are some common uses of the procedure? CT ...

  7. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... are the limitations of CT of the Sinuses? What is CT (Computed Tomography) of the Sinuses? Computed ... nasal cavity by small openings. top of page What are some common uses of the procedure? CT ...

  8. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... News Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography (CT) ... are the limitations of Children's CT? What is Children's CT? Computed tomography, more commonly known as a ...

  9. Computerized tomography and staging of bladder tumors

    International Nuclear Information System (INIS)

    Wozniak, A.; Luongo, A.; Nogueira, A.

    1982-01-01

    Computed Tomography (CT) has been employed in 13 patients with bladder tumors; 8 of them subsequently underwent surgery. Concordance between CT and pathological staging ranged in 90% of accurate results. Our data are discussed and compared to those of other authors in the literature. Staging was carried out according to the International Union Against Cancer. CT proved to be very accurate in the assessment of local and regional spread of tumor, limphatic progression and early detection of ureteral obstruction, as well as diagnosis of distant metastasis in selected patients. In poor candidates for surgery CT provided invaluable data to be used for localizing fields of radiation therapy. CT is a very well tolerated procedure, it is therefore suitable in subsequent treatment control. (Author) [pt

  10. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... vessels. CT examinations are fast and simple; in emergency cases, they can reveal internal injuries and bleeding ... Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to Computed Tomography (CT) - ...

  11. Computed Tomography (CT) -- Head

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    Full Text Available ... of a stroke. a stroke, especially with a new technique called Perfusion CT. brain tumors. enlarged brain ... Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to Computed Tomography (CT) - ...

  12. Computed Tomography (CT) -- Head

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    Full Text Available ... of the Head? What is CT Scanning of the Head? Computed tomography, more commonly known as a ... of page What are some common uses of the procedure? CT scanning of the head is typically ...

  13. Bladder hernia: Multidetector computed tomography findings

    Directory of Open Access Journals (Sweden)

    Ankur Gadodia

    2011-01-01

    Full Text Available Herniation of bladder in inguinal hernia is rare, with most cases diagnosed intraoperatively. Preoperative diagnosis is even rarer. We report a case of bladder as content of inguinal hernia diagnosed using multidetector computed tomography.

  14. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... tomography, more commonly known as a CT or CAT scan, is a diagnostic medical test that, like ... imaging provides real-time imaging, making it a good tool for guiding minimally invasive procedures such as ...

  15. Computed Tomography (CT) - Spine

    Science.gov (United States)

    ... the removal of fluid from a localized infection ( abscess ). In patients with narrowing ( stenosis ) of the spine ... Survey Images × Image Gallery Computed Tomography (CT or CAT scan) equipment View full size with caption Do ...

  16. Computed Tomography (CT) -- Head

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    Full Text Available ... for Brain Tumors Radiation Therapy for Head and Neck Cancer Others American Stroke Association National Stroke Association ... Computer Tomography (CT) Safety During Pregnancy Head and Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine ...

  17. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... tomography (CT) scan. View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. ...

  18. Computed Tomography (CT) -- Head

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    Full Text Available ... tomography (CT) scan. View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. ...

  19. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography (CT) is ... a CT scan. View full size with caption Pediatric Content Some imaging tests and treatments have special ...

  20. Children's (Pediatric) CT (Computed Tomography)

    Science.gov (United States)

    ... Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography (CT) is ... a CT scan. View full size with caption Pediatric Content Some imaging tests and treatments have special ...

  1. Role of Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in Diagnostic Evaluation of Carcinoma Urinary Bladder: Comparison with Computed Tomography

    International Nuclear Information System (INIS)

    Chakraborty, Dhritiman; Mittal, Bhagwant Rai; Kashyap, Raghava; Mete, Utham Kumar; Narang, Vikram; Das, Ashim; Bhattacharya, Anish; Khandelwal, Niranjan; Mandal, Arup K.

    2014-01-01

    Bladder carcinoma is the most frequent tumor of the urinary tract and accounts 7% of all malignancies in men and 2% of all malignancies in women. This retrospective study was carried out to assess the diagnostic utility of F18-fludeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in the imaging evaluation of bladder carcinoma. Seventy-seven consecutive patients diagnosed to have carcinoma urinary bladder referred for F18-FDG PET/CT were included in this study. Thirty-four patients were for initial staging after transurethral biopsy and remaining 43 patients were for restaging. All patients also underwent CT scan of the abdomen and pelvis. PET/CT findings were correlated with diagnostic CT scan and histopathological findings. In 30 of the 34 patients for initial staging, both PET/CT and CT confirmed the primary lesion in the bladder. Histopathology report was available in 23 patients. Lymph nodes FDG uptake reported to be metastatic in 10/23 patients while CT detected lymph node metastasis in 12 patients. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy have been calculated to be 87.5%, 80%, 70%, 92%, 82% for PET/CT and 66%, 57%, 50%, 72%, 60% for CT respectively. PET/CT detected metastatic disease in 8 patients whereas CT detected in 4 patients. Of the 43 patients for restaging, local recurrence was detected in 24 patients on both PET/CT and CT. Histopathology report was available in 17 patients. Sensitivity, specificity, PPV, NPV and accuracy were 85%, 60%, 60%, 85%, 70% for PET/CT and 80%, 50%, 40%, 85%, 58% for CT respectively. Nineteen patients were detected to have metastatic disease by PET/CT, whereas CT detected metastases in 11 patients. F-18 FDG PET/CT is a very useful modality in pre-operative staging and monitoring after surgery, chemotherapy or radiotherapy of patients with carcinoma urinary bladder

  2. Computed Tomography (CT) -- Head

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    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Head ...

  3. Computed Tomography (CT) -- Sinuses

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    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Sinuses ...

  4. Computed Tomography (CT) -- Head

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    Full Text Available ... Computed tomography (CT) of the head uses special x-ray equipment to help assess head injuries, severe headaches, ... is a diagnostic medical test that, like traditional x-rays, produces multiple images or pictures of the inside ...

  5. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... Computed tomography (CT) of the sinuses uses special x-ray equipment to evaluate the paranasal sinus cavities – hollow, ... is a diagnostic medical test that, like traditional x-rays, produces multiple images or pictures of the inside ...

  6. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... risks? What are the limitations of Children's CT? What is Children's CT? Computed tomography, more commonly known ... newborns, infants and older children. top of page What are some common uses of the procedure? CT ...

  7. Bladder diverticulitis on PET/CT

    OpenAIRE

    Wosnitzer, Brian

    2015-01-01

    Diverticula are commonly seen in hollow viscous organs. One common complication of diverticula is infection, known as diverticulitis. Although diverticulitis has been extensively described with respect to the colon, not many cases describe diverticulitis of the urinary bladder. We report a case of diverticulitis of the bladder to emphasize the imaging findings on PET/CT and to discuss management and possible complications.

  8. Positron Emission Tomography - Computed Tomography (PET/CT)

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Positron Emission Tomography - Computed Tomography (PET/CT) Positron emission tomography (PET) ... Emission Tomography – Computed Tomography (PET/CT)? What is Positron Emission Tomography – Computed Tomography (PET/CT) Scanning? Positron emission tomography, ...

  9. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... Videos About Us News Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric ... cross-sectional images generated during a CT scan can be reformatted in multiple planes, and can even ...

  10. Detecting Metastatic Bladder Cancer Using (18)F-Fluorodeoxyglucose Positron-Emission Tomography/Computed Tomography.

    Science.gov (United States)

    Öztürk, Hakan

    2015-10-01

    The purpose of this study was to retrospectively investigate the contribution of (18)F-fluorodeoxyglucose-positron emission tomography/computed tomography ((18)F-FDG-PET/CT) to detection of metastatic bladder cancer. The present study included 79 patients (69 men and 10 women) undergoing (18)F-FDG-PET/CT upon suspicion of metastatic bladder cancer between July 2007 and April 2013. The mean age was 66.1 years with a standard deviation of 10.7 years (range, 21 to 85 years). Patients were required to fast for 6 hours prior to scanning, and whole-body PET scanning from the skull base to the upper thighs was performed approximately 1 hour after intravenous injection of 555 MBq of (18)F-FDG. Whole body CT scanning was performed in the cranio-caudal direction. FDG-PET images were reconstructed using CT data for attenuation correction. Suspicious recurrent or metastatic lesions were confirmed by histopathology or clinical follow-up. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of (18)F-FDG-PET/CT were 89%, 78%, 90%, 75%, and 86%, respectively. (18)F-FDG-PET/CT can detect metastases with high sensitivity and positive predictive values in patients with metastatic bladder carcinoma.

  11. Detection of penile metastasis from bladder cancer using F 18 FDG PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dong Yun; Lee, Jong Jin [Univ. of Ulsan College of Medicine, Seoul (Korea, Republic of)

    2012-12-15

    A 74 year old man who had experienced priapism for 2 months after radical cystectomy for bladder cancer visited our hospital, and underwent metastatic work up {sup 18}F fluorodeoxyglucose (FDG) positron emission tomography/computed tomography(PET/CT)showed diffuse hypermetabolic activity along the penis shaft, which was confirmed as a penile metastasis.

  12. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... a relatively short time, especially when compared to magnetic resonance imaging (MRI). CT scanning is painless, noninvasive and accurate. A ... CT is less sensitive to patient movement than MRI. CT can be performed if you have an ...

  13. Computed Tomography (CT) -- Head

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    Full Text Available ... CT is less sensitive to patient movement than MRI. CT can be performed if you have an implanted medical device of any kind, unlike MRI. A diagnosis determined by CT scanning may eliminate ...

  14. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple slices in a single rotation. These scanners, called multislice CT or multidetector CT, ...

  15. Computed Tomography (CT) -- Head

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    Full Text Available ... view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple slices in a single rotation. These scanners, called multislice CT or multidetector CT, ...

  16. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... Children's (Pediatric) CT (Computed Tomography) Sponsored by Please note RadiologyInfo.org is not a medical facility. Please ... is further reviewed by committees from the American College of Radiology (ACR) and the Radiological Society of ...

  17. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... tomography, more commonly known as a CT or CAT scan, is a diagnostic medical test that, like ... imaging provides real-time imaging, making it a good tool for guiding minimally invasive procedures such as ...

  18. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... Pediatric computed tomography (CT) is a fast, painless exam that uses special x-ray equipment to create ... your doctor and the technologist prior to the exam if your child has a known allergy to ...

  19. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... considerations. The teddy bear denotes child-specific content. Related Articles and Media Radiation Dose in X-Ray ... Materials Anesthesia Safety Children and Radiation Safety Images related to Children's (Pediatric) CT (Computed Tomography) Videos related ...

  20. Diagnosis of preoperative staging of bladder cancer by CT and angiography

    International Nuclear Information System (INIS)

    Munechika, Hirotsugu; Saito, Kazuhiko; Tanaka, Osamu; Tomiie, Fumitaka; Aihara, Toshinori

    1982-01-01

    The accuracy of computed tomography (CT) and angiography in defining the extent of local invasion was studied retrospectively in 19 patients with surgically proven carcinoma of the bladder. The overall accuracy of CT and angiographic staging in these cases was 54 percent and 47 percent respectively. The diagnosis of carcinoma of the bladder by CT tended to do overstaging rather than understaging. A tangential view of the tumor-bearing area by the selective internal iliac arteriography allows an accurate estimation of the perivesical tumor extension. The topographic diagnosis should be made by CT prior to the angiographic study. (author)

  1. Unusual Presentation of Bladder Paraganglioma: Comparison of 131I MIBG SPECT/CT and 68Ga DOTANOC PET/CT

    International Nuclear Information System (INIS)

    Jain, Tarun Kumar; Basher, Rajender Kumar; Gupta, Nitin; Shukla, Jaya; Singh, Shrawan Kumar; Mittal, Bhagwant Rai

    2016-01-01

    Extraadrenal chromaffin cell-related tumors or paragangliomas are rare, especially in the bladder, accounting for less than 1% of cases. We report a 16-year-old boy who presented with hematuria and paroxysmal headache and was found to have a prostatic growth infiltrating the urinary bladder on anatomical imaging. Iodine-131 ( 131 I) metaiodobenzylguanidine (MIBG) whole-body scanning and subsequently gallium-68 ( 68 Ga) DOTANOC positron emission tomography/computed tomography (PET/CT) were performed. The MIBG scan revealed a non-tracer-avid soft-tissue mass, while DOTANOC PET/CT revealed a tracer-avid primary soft-tissue mass involving the urinary bladder and prostate with metastasis to the iliac lymph nodes. He underwent surgical management; histopathology of the surgical specimen revealed a bladder paraganglioma, whereas the prostate was found to be free of tumor

  2. Computed Tomography (CT) -- Head

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    Full Text Available ... images and send an official report to your primary care physician or physician who referred you for ... of soft tissue (particularly the brain, including the disease processes) are less visible on CT scans . CT ...

  3. Computed Tomography (CT) -- Head

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    Full Text Available ... microphone. top of page How does the procedure work? In many ways CT scanning works very much ... head CT scanning. Manufacturers of intravenous contrast indicate mothers should not breastfeed their babies for 24-48 ...

  4. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... scanners to obtain multiple slices in a single rotation. These scanners, called multislice CT or multidetector CT, ... prescribed procedure with your doctor, the medical facility staff and/or your insurance provider to get a ...

  5. Computed Tomography (CT) -- Head

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    Full Text Available ... scanners to obtain multiple slices in a single rotation. These scanners, called multislice CT or multidetector CT, ... prescribed procedure with your doctor, the medical facility staff and/or your insurance provider to get a ...

  6. Computed Tomography (CT) -- Head

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    Full Text Available ... be viewed on a computer monitor, printed on film or transferred to a CD or DVD. CT ... distinguished from one another on an x-ray film or CT electronic image. In a conventional x- ...

  7. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... be viewed on a computer monitor, printed on film or transferred to a CD or DVD. CT ... distinguished from one another on an x-ray film or CT electronic image. In a conventional x- ...

  8. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... top of page What are the benefits vs. risks? Benefits A CT scan is one of the ... CT scans should have no immediate side effects. Risks There is always a slight chance of cancer ...

  9. Computed Tomography (CT) -- Head

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    Full Text Available ... top of page What are the benefits vs. risks? Benefits CT scanning is painless, noninvasive and accurate. ... CT scans should have no immediate side effects. Risks There is always a slight chance of cancer ...

  10. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... time, resulting in more detail and additional view capabilities. Modern CT scanners are so fast that they ... the technologist verifies that the images are of high enough quality for accurate interpretation. The actual CT ...

  11. Computed Tomography (CT) -- Head

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    Full Text Available ... time, resulting in more detail and additional view capabilities. Modern CT scanners are so fast that they ... the technologist verifies that the images are of high enough quality for accurate interpretation. A CT scan ...

  12. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... allows the body parts to be distinguished from one another on an x-ray film or CT ... benefits vs. risks? Benefits A CT scan is one of the safest means of studying the sinuses. ...

  13. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... the nasal cavity by small openings. top of page What are some common uses of the procedure? CT ... information about pregnancy and x-rays. top of page What does the equipment look like? The CT scanner ...

  14. Computed Tomography (CT) -- Head

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    Full Text Available ... a technique called CT angiography. For more information, see the CT Angiography page . top of page How ... is any possibility that they may be pregnant. See the Safety page for more information about pregnancy ...

  15. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... benefits vs. risks? Benefits A CT scan is one of the safest means of studying the sinuses. ... CT scanning provides very detailed images of many types of tissue as well as the lungs, bones, ...

  16. Computed Tomography (CT) -- Head

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    Full Text Available ... DVD. CT images of internal organs, bones, soft tissue and blood vessels provide greater detail than traditional x-rays, particularly of soft tissues and blood vessels. CT scanning provides more detailed information on ...

  17. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... DVD. CT images of internal organs, bones, soft tissue and blood vessels provide greater detail than traditional x-rays, particularly of soft tissues and blood vessels. A CT scan of the face produces ...

  18. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ... actual CT scanning is performed. Depending on the type of CT scan, the machine may make several ...

  19. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... to a CD or DVD. CT images of internal organs, bones, soft tissue and blood vessels provide ... clicking and whirring sounds as the CT scanner's internal parts, not usually visible to you, revolve around ...

  20. Computed Tomography (CT) -- Head

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    Full Text Available ... view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ... to urinate; however, this is actually a contrast effect and subsides quickly. When you enter the CT ...

  1. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ... to urinate; however, this is actually a contrast effect and subsides quickly. When you enter the CT ...

  2. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... sinus cavities – hollow, air-filled spaces within the bones of the face surrounding the nasal cavity. CT ... CD or DVD. CT images of internal organs, bones, soft tissue and blood vessels provide greater detail ...

  3. Computed Tomography (CT) -- Head

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    Full Text Available ... see the CT Angiography page . top of page How should I prepare? You should wear comfortable, loose- ... of a speaker and microphone. top of page How does the procedure work? In many ways CT ...

  4. Computed Tomography (CT) -- Head

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    Full Text Available ... a stroke. a stroke, especially with a new technique called Perfusion CT. brain tumors. enlarged brain cavities ( ... brain. assess aneurysms or arteriovenous malformations through a technique called CT angiography. For more information, see the ...

  5. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... resulting in more detail and additional view capabilities. Modern CT scanners are so fast that they can ... to ensure that you are properly positioned. With modern CT scanners, you will hear only slight buzzing, ...

  6. Computed Tomography (CT) -- Head

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    Full Text Available ... resulting in more detail and additional view capabilities. Modern CT scanners are so fast that they can ... to ensure that you are properly positioned. With modern CT scanners, you will hear only slight buzzing, ...

  7. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... CT scanner is typically a large, box-like machine with a hole, or short tunnel, in the ... Then, the table will move slowly through the machine as the actual CT scanning is performed. Depending ...

  8. Computed Tomography (CT) -- Head

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    Full Text Available ... CT scanner is typically a large, box-like machine with a hole, or short tunnel, in the ... Then, the table will move slowly through the machine as the actual CT scanning is performed. Depending ...

  9. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ... the technologist verifies that the images are of high enough quality for accurate interpretation. The actual CT ...

  10. Computed Tomography (CT) -- Head

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    Full Text Available ... view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ... the technologist verifies that the images are of high enough quality for accurate interpretation. A CT scan ...

  11. Computed Tomography (CT) -- Head

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    Full Text Available ... which may be causing hearing problems. determine whether inflammation or other changes are present in the paranasal ... CT scans . CT is not sensitive in detecting inflammation of the meninges —the membranes covering the brain. ...

  12. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... air-filled spaces within the bones of the face surrounding the nasal cavity. CT scanning is painless, ... and blood vessels. A CT scan of the face produces images that also show a patient's paranasal ...

  13. Computed Tomography (CT) -- Head

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    Full Text Available ... full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. Related Articles and Media Radiation Dose in X-Ray and CT Exams Blood Clots CT Perfusion of the Head CT Angiography ( ...

  14. Diagnosis of clinical staging of bladder cancer by CT and angiography

    International Nuclear Information System (INIS)

    Kobayashi, Isao; Igawa, Mikio; Ohnishi, Yoshio; Nakano, Hiroshi; Nihira, Hiromi; Mori, Masaki; Okada, Mitsuo.

    1984-01-01

    The preoperative staging of bladder cancer is of fundamental importance for prognostic evaluation and surgical indication. We studied the accuracy of computed tomography (CT) and angiography in defining the extent of local invasion in 16 patients with surgically proven carcinoma of the bladder. The overall accuracy of CT and angiographic staging in these cases was 75 % and 50 % respectively. In low stage, the accuracy was 90 % in CT and 70 % in angiography. In high stage, the accuracy was 50 % in CT and 16.7 % in angiography. Our results seems to indicate lower accuracy in high stage bladder cancer compared with other research. Data from a much larger series are required to ascertain whether the additional information provided by CT and angiography will produce any improvement in patient management. (author)

  15. Computed Tomography (CT) -- Head

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    Full Text Available ... a history of heart disease, asthma, diabetes, kidney disease or thyroid problems. Any of these conditions may increase the ... or any disorder of the heart, kidneys or thyroid gland , or if you ... brain, including the disease processes) are less visible on CT scans . CT ...

  16. Computed Tomography (CT) -- Head

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    Full Text Available ... diseases than regular radiographs (x-rays). top of page What are some common uses of the procedure? CT ... information about pregnancy and x-rays. top of page What does the equipment look like? The CT scanner ...

  17. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... images or pictures of the inside of the body. The cross-sectional images generated during a CT scan can be reformatted ... of data to create two-dimensional cross-sectional images of your body, which are then displayed on a monitor. CT ...

  18. Computed Tomography (CT) -- Head

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    Full Text Available ... images or pictures of the inside of the body. The cross-sectional images generated during a CT scan can be reformatted ... of data to create two-dimensional cross-sectional images of your body, which are then displayed on a monitor. CT ...

  19. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... time staying still, are claustrophobic, or have chronic pain, you may find a CT exam to be stressful. The technologist or nurse, under the direction of a physician, may offer you some medication to help you tolerate the CT scanning procedure. ...

  20. Computed Tomography (CT) -- Head

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    Full Text Available ... time staying still, are claustrophobic or have chronic pain, you may find a CT exam to be stressful. The technologist or nurse, under the direction of a physician, may offer you some medication to help you tolerate the CT scanning procedure. ...

  1. Computed Tomography (CT) -- Head

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    Full Text Available ... page How does the procedure work? In many ways CT scanning works very much like other x-ray examinations. Different body parts absorb the x-rays ... time. Follow-up examinations are sometimes the best way to see if treatment is working or if a ... conventional x-rays, CT scanning provides very detailed images of many ...

  2. Computed Tomography (CT) -- Head

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    Full Text Available ... microphone. top of page How does the procedure work? In many ways CT scanning works very much like other x-ray examinations. Different ... bleeding quickly enough to help save lives. CT has been shown to be a cost-effective imaging ...

  3. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... microphone. top of page How does the procedure work? In many ways CT scanning works very much like other x-ray examinations. Different ... bleeding quickly enough to help save lives. CT has been shown to be a cost-effective imaging ...

  4. Computed Tomography (CT) -- Head

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    Full Text Available ... stable or changed over time. top of page What are the benefits vs. risks? Benefits CT scanning is painless, noninvasive and accurate. A major advantage of CT is its ability to image bone, soft tissue and blood vessels all at the same time. ...

  5. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... done with low-dose technique. top of page What are the limitations of CT of the Sinuses? CT is usually the first test ordered when a sinus tumor is suspected. If additional information is needed to determine the extent of soft tissue of the tumor, magnetic resonance imaging (MRI) may ...

  6. Computed Tomography (CT) -- Head

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    Full Text Available ... objects, including jewelry, eyeglasses, dentures and hairpins, may affect the CT images and should be left at ... of the examination the same way that it affects photographs. If contrast material is used, depending on ...

  7. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... have a history of heart disease, asthma, diabetes, kidney disease or thyroid problems. Any of these conditions may ... hard time staying still, are claustrophobic or have chronic pain, you may find a CT exam to ...

  8. Computed Tomography (CT) -- Head

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    Full Text Available ... of page Additional Information and Resources RTAnswers.org Radiation Therapy for Head and Neck Cancer top of page This page was reviewed on June 21, 2016 Send us your feedback Did you find the information you were looking for? ... Resonance Imaging (MRI) - Head Head and Neck Cancer Treatment Radiation Dose in X-Ray and CT Exams Contrast ...

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    Full Text Available ... may increase the risk of an unusual adverse effect. Women should always inform their physician and the CT technologist if there is any possibility that they may be pregnant. See the Safety page for more information about pregnancy ...

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    Full Text Available ... images or pictures of the inside of the body. The cross-sectional images generated during a CT scan can be reformatted ... at and passes through the part of the body being examined, recording an image on a special electronic image recording plate. Bones ...

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  2. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... of page Additional Information and Resources RTAnswers.org Radiation Therapy for Head and Neck Cancer top of page This page was reviewed on March 30, 2018 Send us your feedback Did you find the information you were looking for? ... Resonance Imaging (MRI) - Head Head and Neck Cancer Treatment Radiation Dose in X-Ray and CT Exams Contrast ...

  3. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... 10 minutes. top of page What will I experience during and after the procedure? CT exams are ... areas. Outside links: For the convenience of our users, RadiologyInfo .org provides links to relevant websites. RadiologyInfo. ...

  4. Computed Tomography (CT) -- Head

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    Full Text Available ... 10 minutes. top of page What will I experience during and after the procedure? CT exams are ... areas. Outside links: For the convenience of our users, RadiologyInfo .org provides links to relevant websites. RadiologyInfo. ...

  5. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... in direct visual contact and usually with the ability to hear and talk to you with the use of a speaker and microphone. top of page How does the procedure work? In many ways CT scanning works very much like other x-ray examinations. Different body parts absorb the x-rays in varying ...

  6. Computed Tomography (CT) -- Head

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    Full Text Available ... in direct visual contact and usually with the ability to hear and talk to you with the use of a speaker and microphone. top of page How does the procedure work? In many ways CT scanning works very much like other x-ray examinations. Different body parts absorb the x-rays in varying ...

  7. Computed Tomography (CT) -- Head

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    Full Text Available ... Rotating around you, the x-ray tube and electronic x-ray detectors are located opposite each other ... another on an x-ray film or CT electronic image. In a conventional x-ray exam, a ...

  8. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... Rotating around you, the x-ray tube and electronic x-ray detectors are located opposite each other ... another on an x-ray film or CT electronic image. In a conventional x-ray exam, a ...

  9. Computed Tomography (CT) -- Head

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    Full Text Available ... operates the scanner and monitors your examination in direct visual contact and usually with the ability to hear and talk to you with the use of a speaker and microphone. top of page How does the procedure work? In many ways CT scanning works very much ...

  10. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... operates the scanner and monitors your examination in direct visual contact and usually with the ability to hear and talk to you with the use of a speaker and microphone. top of page How does the procedure work? In many ways CT scanning works very much ...

  11. Detection of bladder tumors using optical coherence tomography

    Science.gov (United States)

    Pan, Yingtian; Xie, Tuqiang; Wang, Zhenguo

    2004-07-01

    This paper summarizes the engineering development of our lab for endoscopic optical coherence tomography toward the ultimate goal to image bladder micro architecture and to diagnose bladder cancers. To test the utility and potential limitations of OCT setups for bladder tumor diagnosis, we used a rat bladder cancer model to track the morphological changes following tumor growth. Image results are presented, suggesting that OCT is able to differentiate cancerous lesions from inflammatory lesions based on OCT characterizations of epithelial thickness and backscattering changes of bladder tissue.

  12. Generic method for automatic bladder segmentation on cone beam CT using a patient-specific bladder shape model

    International Nuclear Information System (INIS)

    Schoot, A. J. A. J. van de; Schooneveldt, G.; Wognum, S.; Stalpers, L. J. A.; Rasch, C. R. N.; Bel, A.; Hoogeman, M. S.; Chai, X.

    2014-01-01

    Purpose: The aim of this study is to develop and validate a generic method for automatic bladder segmentation on cone beam computed tomography (CBCT), independent of gender and treatment position (prone or supine), using only pretreatment imaging data. Methods: Data of 20 patients, treated for tumors in the pelvic region with the entire bladder visible on CT and CBCT, were divided into four equally sized groups based on gender and treatment position. The full and empty bladder contour, that can be acquired with pretreatment CT imaging, were used to generate a patient-specific bladder shape model. This model was used to guide the segmentation process on CBCT. To obtain the bladder segmentation, the reference bladder contour was deformed iteratively by maximizing the cross-correlation between directional grey value gradients over the reference and CBCT bladder edge. To overcome incorrect segmentations caused by CBCT image artifacts, automatic adaptations were implemented. Moreover, locally incorrect segmentations could be adapted manually. After each adapted segmentation, the bladder shape model was expanded and new shape patterns were calculated for following segmentations. All available CBCTs were used to validate the segmentation algorithm. The bladder segmentations were validated by comparison with the manual delineations and the segmentation performance was quantified using the Dice similarity coefficient (DSC), surface distance error (SDE) and SD of contour-to-contour distances. Also, bladder volumes obtained by manual delineations and segmentations were compared using a Bland-Altman error analysis. Results: The mean DSC, mean SDE, and mean SD of contour-to-contour distances between segmentations and manual delineations were 0.87, 0.27 cm and 0.22 cm (female, prone), 0.85, 0.28 cm and 0.22 cm (female, supine), 0.89, 0.21 cm and 0.17 cm (male, supine) and 0.88, 0.23 cm and 0.17 cm (male, prone), respectively. Manual local adaptations improved the segmentation

  13. Generic method for automatic bladder segmentation on cone beam CT using a patient-specific bladder shape model

    Energy Technology Data Exchange (ETDEWEB)

    Schoot, A. J. A. J. van de, E-mail: a.j.schootvande@amc.uva.nl; Schooneveldt, G.; Wognum, S.; Stalpers, L. J. A.; Rasch, C. R. N.; Bel, A. [Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam (Netherlands); Hoogeman, M. S. [Department of Radiation Oncology, Daniel den Hoed Cancer Center, Erasmus Medical Center, Groene Hilledijk 301, 3075 EA Rotterdam (Netherlands); Chai, X. [Department of Radiation Oncology, Stanford University School of Medicine, 875 Blake Wilbur Drive, Palo Alto, California 94305 (United States)

    2014-03-15

    Purpose: The aim of this study is to develop and validate a generic method for automatic bladder segmentation on cone beam computed tomography (CBCT), independent of gender and treatment position (prone or supine), using only pretreatment imaging data. Methods: Data of 20 patients, treated for tumors in the pelvic region with the entire bladder visible on CT and CBCT, were divided into four equally sized groups based on gender and treatment position. The full and empty bladder contour, that can be acquired with pretreatment CT imaging, were used to generate a patient-specific bladder shape model. This model was used to guide the segmentation process on CBCT. To obtain the bladder segmentation, the reference bladder contour was deformed iteratively by maximizing the cross-correlation between directional grey value gradients over the reference and CBCT bladder edge. To overcome incorrect segmentations caused by CBCT image artifacts, automatic adaptations were implemented. Moreover, locally incorrect segmentations could be adapted manually. After each adapted segmentation, the bladder shape model was expanded and new shape patterns were calculated for following segmentations. All available CBCTs were used to validate the segmentation algorithm. The bladder segmentations were validated by comparison with the manual delineations and the segmentation performance was quantified using the Dice similarity coefficient (DSC), surface distance error (SDE) and SD of contour-to-contour distances. Also, bladder volumes obtained by manual delineations and segmentations were compared using a Bland-Altman error analysis. Results: The mean DSC, mean SDE, and mean SD of contour-to-contour distances between segmentations and manual delineations were 0.87, 0.27 cm and 0.22 cm (female, prone), 0.85, 0.28 cm and 0.22 cm (female, supine), 0.89, 0.21 cm and 0.17 cm (male, supine) and 0.88, 0.23 cm and 0.17 cm (male, prone), respectively. Manual local adaptations improved the segmentation

  14. Thin-section CT with air insufflation technique for bladder carcinoma: CT findings of superficial bladder carcinoma

    International Nuclear Information System (INIS)

    Kim, Hyun; Song, Ha Hun; Kim, Mi Hye; Lee, Eun Ja; Kim, Young Sin; Kang, Si Won; Shinn, Kyung Sub

    1994-01-01

    The staging of bladder carcinoma is a major determinant of operative management CT of bladder carcinoma has been widely used to diagnose external extension (pT3b and over), but tumors confined to the bladder wall (from pT1 to pT3a) are poorly delineated. The authors describe CT findings of the superficial bladder carcinoma (below T1, stage A) in thin-section CT with air insufflation technique (air insufflation-CT) to facilitate early detection and to aid correct staging of the superficial bladder carcinoma. The materials consisted of proved 24 cases (19 patients, single tumor: 16 patients, multiple tumors: 3 patients) of stage A bladder carcinomas. Air insufflation-CT was performed by the infusion of approximately 200 mL of air into the bladder via a Foley catheter. After the routine pelvic CT, bladder tumors were re-scanned with 1.5 to 5 mm thickness and intervals. The superficial bladder carcinoma were detected as nodular(5 cases, 20.8%), papillary(15 cases, 62.5%), pyramida(2 cases, 8.3%), and domed(2 cases, 8.3%) forms on air insufflation-CT. These tumors were classified into three types according to the size of the tumoral neck: type I(pedundulated polypoid tumor: 4 cases, 16.6%), type II(polypid tumor with short neck: 13 cases, 54.2%), and type III(sessile tumor: 7 cases, 29.2%). The mean size(tumoral width x height x base c neck/stalk) of the tumors was 22 x 20 x 16mm. The average tumoral sizes according to each type of the superficial tumors were type I: 22 x 25 x 6mm, type II: 23 x 22 x 18mm, and type III: 18 x 15 x 18mm. The mean width of the type I-II tumoral necks was 15mm. The mean length of the type I tumoral neck(pedicle) was 2.5mm. Papillary fronds of the tumors were seen in 10 cases(41.7%) of 24 superficial tumors. Outer margin of the involved bladder wall was smooth in all cases. Thin-section CT with air insufflation technique for bladder carcinoma was useful in tumoral demonstration, and characteristics of the superficial bladder carcinomas were

  15. Cone Beam CT Imaging Analysis of Interfractional Variations in Bladder Volume and Position During Radiotherapy for Bladder Cancer

    International Nuclear Information System (INIS)

    Yee, Don; Parliament, Matthew; Rathee, Satyapal; Ghosh, Sunita; Ko, Lawrence; Murray, Brad

    2010-01-01

    Purpose: To quantify daily bladder size and position variations during bladder cancer radiotherapy. Methods and Materials: Ten bladder cancer patients underwent daily cone beam CT (CBCT) imaging of the bladder during radiotherapy. Bladder and planning target volumes (bladder/PTV) from CBCT and planning CT scans were compared with respect to bladder center-of-mass shifts in the x (lateral), y (anterior-posterior), and z (superior-inferior) coordinates, bladder/PTV size, bladder/PTV margin positions, overlapping areas, and mutually exclusive regions. Results: A total of 262 CBCT images were obtained from 10 bladder cancer patients. Bladder center of mass shifted most in the y coordinate (mean, -0.32 cm). The anterior bladder wall shifted the most (mean, -0.58 cm). Mean ratios of CBCT-derived bladder and PTV volumes to planning CT-derived counterparts were 0.83 and 0.88. The mean CBCT-derived bladder volume (± standard deviation [SD]) outside the planning CT counterpart was 29.24 cm 3 (SD, 29.71 cm 3 ). The mean planning CT-derived bladder volume outside the CBCT counterpart was 47.74 cm 3 (SD, 21.64 cm 3 ). The mean CBCT PTV outside the planning CT-derived PTV was 47.35 cm 3 (SD, 36.51 cm 3 ). The mean planning CT-derived PTV outside the CBCT-derived PTV was 93.16 cm 3 (SD, 50.21). The mean CBCT-derived bladder volume outside the planning PTV was 2.41 cm 3 (SD, 3.97 cm 3 ). CBCT bladder/ PTV volumes significantly differed from planning CT counterparts (p = 0.047). Conclusions: Significant variations in bladder and PTV volume and position occurred in patients in this trial.

  16. Primary cT2 bladder cancer. A good candidate for radiotherapy combined with cisplatin for bladder preservation

    International Nuclear Information System (INIS)

    Hara, Takahiko; Nishijima, Jun; Miyachika, Yoshihiro; Yamamoto, Yoshiaki; Sakano, Shigeru; Matsuyama, Hideyasu

    2011-01-01

    Bladder preservation therapy (BPT) has been attempted for patients with localized muscle-invasive bladder cancer. However, the indication for BPT has not yet been established. To identify patients who are good candidates for BPT, we evaluated our long-term experience with chemoradiation therapy (CRT) for bladder preservation. Between 1994 and 2009, 82 patients with bladder cancer (clinical stage T2-N0M0) without concurrent upper urinary tract urothelial cancer were treated with CRT. Before CRT, the patients had a biopsy or resection of the tumor by transurethral resection (TUR). The response to CRT was evaluated by TUR, urine cytology and computed tomography. Thirty-two cases (39.0%) had a pathological complete response (pCR) that was defined as no microscopic residual tumor in the bladder. After TUR, 69 cases (84.0%) achieved local control of the cancer, which was considered as a clinical complete response (cCR). There was no significant association between achievement of pCR and examined parameters. The long-term results of CRT were evaluated in cCR cases. The median follow-up was 42.8 months (range, 4.1-155.1). The 5-year overall survival rate was 77.7% and 5-year progression-free survival rate was 64.5%. Clinical T stage and type of tumor (primary or recurrence) were predictive factors for overall survival as well as progression-free survival. In addition, primary cT2 cases had significantly better prognosis than cT3-4 and recurrent cases in overall survival and progression-free survival (P=0.008 and P=0.046, respectively). Cases with a primary cT2 tumor could be good candidates for BPT with radiation combined with cisplatin. (author)

  17. Forced diuresis 18F-fluorodeoxyglucose positron emission tomography/contrast enhanced in detection of carcinoma of urinary bladder diverticulum

    International Nuclear Information System (INIS)

    Soundararajan, Ramya; Singh, Harmandeep; Arora, Saurabh; Nayak, Brusabhanu; Shamim, Shamim Ahmed; Bal, Chandrasekhar; Kumar, Rakesh

    2015-01-01

    Urinary bladder diverticular carcinomas are uncommon with a lesser incidence of 0.8–10% and its diagnosis still remains a challenge. Cystoscopy is the most reliable method, but evaluating diverticulum with narrow orifices is difficult. Before the initiation of appropriate treatment, proper detection of bladder diverticular carcinoma and its locoregional and distant sites of involvement is necessary. Here, we present a case of 48-year-old male with urinary bladder diverticular carcinoma detected by forced diuretic 18 F-fluorodeoxyglucose positron emission tomography/computerized tomography ( 18 F-FDG PET/CT). This case also highlights the significance of forced diuretic 18 F-FDG PET/CT in the detection, staging, and response evaluation of bladder diverticular carcinoma

  18. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... on newborns, infants and older children. top of page What are some common uses of the procedure? CT ... your child for the CT examination. top of page What does the CT equipment look like? The CT ...

  19. Bladder transitional cell carcinoma: correlation of contrast enhancement on computed tomography with histological grade and tumour angiogenesis

    International Nuclear Information System (INIS)

    Xie, Q.; Zhang, J.; Wu, P.-H.; Jiang, X.-Q.; Chen, S.-L.; Wang, Q.-L.; Xu, J.; Chen, G.-D.; Deng, J.-H.

    2005-01-01

    AIM: To investigate the correlation between the degree of contrast enhancement of bladder cancer in the early enhanced phase of helical computed tomography (CT) and microvessel density (MVD), vascular endothelial growth factor (VEGF) and histological grade. MATERIALS AND METHODS: Sixty-five patients with transitional cell carcinoma of the bladder were examined by incremental unenhanced CT and helical CT at 40-45 s after initiation of intravenous administration of contrast medium before surgery. The CT density in Hounsfield units of bladder carcinomas were measured in the middle of the maximum diameter section of the cancer lesions on unenhanced and enhanced CT. The degree of contrast enhancement of the tumour was determined as the absolute increase in Hounsfield units. Histological grade, VEGF and MVD were analysed for each cancer. The Pearson and Spearman correlation tests were used to determine the strength of the relationships between CT enhancement and histological grade, VEGF expression and MVD. RESULTS: Different degrees of enhancement were observed in 91 cancers during the early enhanced phase of helical CT. Mean MVDs and mean CT enhancing values of different histological grade groups were statistically different (p<0.001). A positive correlation was found in the CT-enhancing value of bladder cancer and MVD (Pearson correlation test; r=0.938, p<0.001) and histological grade (Spearman rank correlation; r=0.734, p<0.001). VEGF of bladder cancer did not correlate with the change in CT attenuation (Spearman rank correlation; r=0.087, p=0.410) and MVD (Spearman rank correlation, r=0.103, p=0.330). CONCLUSION: In bladder cancer, the degree of contrast enhancement during the early enhanced helical CT is correlated with the MVD and histological grade of tumour. It is possible that MVD is the histopathological basis of early contrast enhancement of bladder cancer

  20. Computed tomography in staging of bladder carcinoma (Prospective study)

    International Nuclear Information System (INIS)

    Lee, Kyung Soo; Choi, Byung Ihn; Han, Man Chung

    1985-01-01

    Staging of carcinoma of the urinary bladder is important for the choice of therapy and also has prognostic implications. Hitherto the staging has been based upon cystoscopy with biopsy, transurethral resection, and palpation with complementary radiographic examinations such as cystography, urography, lymphangiography, ultrasound and angiography. However, with all these methods, the staging of bladder carcinomas still uncertain and inferior to CT. Authors analyzed CT staging of bladder cancers and compared with pathologic staging of laparotomy results. The results are as following: 1. Overall accuracy of CT staging in bladder carcinoma was 72 percent. 2. Overstaging was 20 percent (5/25) and understaging was 8 percent (2/25). 3. All of CT stage B cancers were proven to be stage B, pathologically. 4. In 6 cases of CT static cancers, only one was correct, 3 were overstaged and 2 were understaged. 5. In 7 cases of CT stage D cancers, 5 were correct and 2 were overstaged. 6. CT detected only 2 cases of pelvic lymph node involvement in 4 of pathologically proven lymphadenopathy

  1. PET/CT in renal, bladder and testicular cancer

    Science.gov (United States)

    Bouchelouche, Kirsten; Physician, Chief; Choyke, Peter L.

    2015-01-01

    Imaging plays an important role in the clinical management of cancer patients. Hybrid imaging with PET/CT is having a broad impact in oncology, and in recent years PET/CT is beginning to have an impact in uro-oncology as well. In both bladder and renal cancer there is a need to study the efficacy of other tracers than F-18 fluorodeoxyglucose (FDG), particularly tracers with only limited renal excretion. Thus, new tracers are being introduced in these malignancies. This review focuses on the clinical role of FDG and other PET agents in renal, bladder and testicular cancer. PMID:26099672

  2. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... CT is less sensitive to patient movement than MRI. CT can be performed if you have an implanted medical device of any kind, unlike MRI. CT imaging provides real-time imaging, making it ...

  3. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... view of the body's interior. Refinements in detector technology allow new CT scanners to obtain multiple slices in a single rotation. These scanners, called "multislice CT" or "multidetector CT," ...

  4. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... child for the CT examination. top of page What does the CT equipment look like? The CT scanner is typically a large machine with a hole, or short tunnel, in the center. A moveable ...

  5. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... beneficial for all patients but especially children, the elderly and critically ill. For some CT exams, a ... clinical problems. CT is less sensitive to patient movement than MRI. CT can be performed if you ...

  6. Computed tomography (CT) of orbital cellulitis

    Energy Technology Data Exchange (ETDEWEB)

    Nakashima, H.; Hara, K.; Okamura, R.; Watanabe, T.; Nagata, M. (Kumamoto Univ. (Japan). School of Medicine)

    1981-12-01

    Two cases of orbital cellulitis showed a tumor-like shadow in the orbit on CT examination. Abnormal shadows were also noticed in both cases in the frontal and ethmoid sinuses. Postoperatively, one case was diagnosed as pyocele of the frontal sinus, the other as sinusitis with subperitoneal hematoma. In these diagnoses, plane skull X-P, tomography and CT scanning were valuable.

  7. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... scanners to obtain multiple slices in a single rotation. These scanners, called "multislice CT" or "multidetector CT," ... prescribed procedure with your doctor, the medical facility staff and/or your insurance provider to get a ...

  8. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... images or pictures of the inside of the body. The cross-sectional images generated during a CT ... be performed to evaluate blood vessels throughout the body. With CT, it is possible to obtain very ...

  9. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... CT scans that are not clearly needed. Another strategy is to consider other tests, such as MRI ... sensitive to radiation, they should have a CT study only if it is essential for making a ...

  10. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... top of page What are the benefits vs. risks? Benefits Using a multidetector CT unit to examine ... CT scans should have no immediate side effects. Risks The risk of serious allergic reaction to contrast ...

  11. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... such as inflammation of the bronchi (breathing passages) birth defects trauma to blood vessels or lung CT ... used to: diagnose appendicitis detect abdominal tumors or birth defects In the pelvic region, CT scans can ...

  12. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... medications and allergies. Inform your doctor and the technologist prior to the exam if your child has ... exam. This can be discussed with the CT technologist, the specialist who will be performing the CT ...

  13. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... to wear a lead apron to prevent radiation exposure. The radiation dose directly outside of the CT ... However, CT scans result in a low-level exposure. Whether such levels cause cancer is debatable but ...

  14. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... the body, in a shorter period of time. Modern CT scanners are so fast that they can ... ensure that he/she is properly positioned. With modern CT scanners, your child will hear only slight ...

  15. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... outside of the CT scanner itself is very low. If you suspect you may be pregnant, however, ... cause cancer. However, CT scans result in a low-level exposure. Whether such levels cause cancer is ...

  16. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... CT is used to help diagnose a wide range of conditions due to injury or illness. In ... a cost-effective imaging tool for a wide range of clinical problems. CT is less sensitive to ...

  17. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... is faster than the older CT scanners, reducing the need for sedation and general anesthesia. New technologies that ... A diagnosis determined by CT scanning may eliminate the need for exploratory surgery and surgical biopsy. No radiation ...

  18. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... with the CT technologist or nurse at the time of the CT examination. If your child has ... detectors rotate around the patient. At the same time, the examination table is moving through the scanner, ...

  19. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... of page What are some common uses of the procedure? CT is used to help diagnose a ... top of page How should we prepare for the CT scan? Your child should wear comfortable, loose- ...

  20. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... trauma to blood vessels or lung CT is well-suited for visualizing diseases or injury of important ... detailed images of many types of tissue as well as the lungs, bones, and blood vessels. CT ...

  1. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... obtain CT images. It is known that high levels of radiation may cause cancer. However, CT scans result in a low-level exposure. Whether such levels cause cancer is debatable ...

  2. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... detail than traditional x-rays, particularly of soft tissues and blood vessels. CT scans may be performed on newborns, infants and older children. top of page What are some common uses of the procedure? CT ...

  3. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... multislice CT" or "multidetector CT," allow thinner slices to be obtained, resulting in more detail of the body, in a shorter period of time. Modern CT scanners are so fast that they can scan through large sections of the body in just a few seconds. Such speed is beneficial for ...

  4. Multidetector CT cystography for imaging colovesical fistulas and iatrogenic bladder leaks.

    Science.gov (United States)

    Tonolini, Massimo; Bianco, Roberto

    2012-04-01

    Multidetector computed tomography (MDCT) cystography currently represents the modality of choice to image the urinary bladder in traumatized patients. In this review we present our experience with MDCT cystography applications outside the trauma setting, particularly for diagnosing bladder fistulas and leaks. A detailed explanation is provided concerning exam preparation, acquisition technique, image reconstruction and interpretation. Colovesical fistulas most commonly occur as a complication of sigmoid diverticular disease, and often remain occult after extensive diagnostic work-up including cystoscopy and contrast-enhanced CT. We consistently achieved accurate preoperative visualization of colovesical fistulas using MDCT cystography. Urinary leaks and injuries represent a non-negligible occurrence after pelvic surgery, particularly obstetric and gynaecological procedures: in our experience MDCT cystography is useful to investigate iatrogenic bladder leaks or fistulas. In our opinion, MDCT cystography should be recommended as the first line modality for direct visualization or otherwise confident exclusion of both spontaneous enterovesical fistulas and bladder injuries following instrumentation procedures, obstetric or surgical interventions. Main Messages • Explanation of exam preparation, acquisition technique, image reconstruction and interpretation. • Preoperative visualization of colovesical fistulas, usually secondary to sigmoid diverticulitis. • Visualization or exclusion of iatrogenic bladder injuries following instrumentation or surgery.

  5. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... or lung CT is well-suited for visualizing diseases or injury of important organs in the abdomen including the liver, kidney and spleen. CT is sometimes used to: diagnose appendicitis detect abdominal tumors or birth defects In ...

  6. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... many ways, CT scanning is like other x-ray examinations. X-rays are a form of radiation, like light ... denotes child-specific content. Related Articles and Media Radiation Dose in X-Ray and CT Exams Contrast Materials Anesthesia Safety ...

  7. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... CT equipment look like? How does the procedure work? How is the procedure performed? What will my child experience during and after the procedure? Who interprets the results and how do we get them? What are the benefits vs. risks? What are the limitations of Children's CT? What ...

  8. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... top of page What are the benefits vs. risks? Benefits Using a multidetector CT unit to examine children is faster than the older CT scanners, reducing the need for sedation and general anesthesia. New technologies that will make even faster scanning possible are ...

  9. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... as the lungs, bones, and blood vessels. CT examinations are fast and simple; in emergency cases, they can reveal internal injuries and bleeding quickly enough to help save lives. CT has been shown to be a cost-effective imaging tool for a wide range of clinical ...

  10. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... x-ray exam, a small burst of radiation passes through the body, recording an image on photographic ... of CT scan, the machine may make several passes. Patients may be asked to hold their breath ...

  11. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... CT of the chest is used to evaluate: complications from infections such as pneumonia a tumor that ... radiation dose. There always is a risk of complications from general anesthesia or sedation. Every measure will ...

  12. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... scanner is typically a large machine with a hole, or short tunnel, in the center. A moveable ... up in shades of gray and air appears black. With CT scanning, numerous x-ray beams and ...

  13. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... there is a history of heart disease, asthma, diabetes, kidney disease or thyroid problems. Any of these ... radiation children may receive from a CT scan. One of the best ways of limiting radiation exposure ...

  14. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... imaging provides real-time imaging, making it a good tool for guiding minimally invasive procedures such as ... areas of the body that sometimes are as good as or better than those obtained by CT ...

  15. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... beneficial for all patients but especially children, the elderly and critically ill. For some CT exams, a ... the need for sedation and general anesthesia. New technologies that will make even faster scanning possible are ...

  16. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... evaluation with additional views or a special imaging technique. A follow-up examination may also be necessary ... Sometimes ultrasound is substituted for CT as a method of imaging in these procedures in children. A ...

  17. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... CT scan. View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. Related Articles and Media Radiation Dose in X- ...

  18. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... be viewed on a computer monitor, printed on film or transferred to a CD or DVD. CT ... through the body, recording an image on photographic film or a special image recording plate . Bones appear ...

  19. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... view of the body's interior. Refinements in detector technology allow new CT scanners to obtain multiple slices ... the need for sedation and general anesthesia. New technologies that will make even faster scanning possible are ...

  20. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... tissues show up in shades of gray and air appears black. With CT scanning, numerous x-ray ... determines that the images are of high enough quality for the radiologist to read. top of page ...

  1. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... may have a warm, flushed sensation during the injection of the contrast materials and a metallic taste ... CT scans that are not clearly needed. Another strategy is to consider other tests, such as MRI ...

  2. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... vessels. CT examinations are fast and simple; in emergency cases, they can reveal internal injuries and bleeding ... may eliminate the need for exploratory surgery and surgical biopsy. No radiation remains in a patient's body ...

  3. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... of imaging in these procedures in children. A diagnosis determined by CT scanning may eliminate the need ... needed diagnostic information. The benefit of an accurate diagnosis far outweighs the risk. See the Safety page ...

  4. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... determines that the images are of high enough quality for the radiologist to read. top of page ... in CT scans should have no immediate side effects. Risks The risk of serious allergic reaction to ...

  5. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... for the chest x-ray, CT is the most commonly used imaging procedure for evaluating the chest. ... scanning, especially if the chest is being scanned. Most children older than six years are able to ...

  6. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... injuries and bleeding quickly enough to help save lives. CT has been shown to be a cost- ... the reason for the exam, the body area being examined, and the child's size. Radiologists generally attempt ...

  7. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... injuries and bleeding quickly enough to help save lives. CT has been shown to be a cost- ... to protect the welfare of your child, including close monitoring. Because children are more sensitive to radiation, ...

  8. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... sometimes compared to looking into a loaf of bread by cutting the loaf into thin slices. When ... known that high levels of radiation may cause cancer. However, CT scans result in a low-level ...

  9. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... sits. The technologist will always be able to see your child in the CT scanner. top of ... scan. However, the technologist will be able to see, hear and speak with your child at all ...

  10. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... in CT scans should have no immediate side effects. Risks The risk of serious allergic reaction to ... of an accurate diagnosis far outweighs the risk. See the Safety page for more information about radiation ...

  11. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... its ability to image bone, soft tissue and blood vessels all at the same time. Unlike conventional x-rays, CT scanning provides very detailed images of many types of tissue as well as the lungs, bones, ...

  12. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... diagnose a wide range of conditions due to injury or illness. In children, CT is typically used to diagnose causes of abdominal pain, evaluate for injury after trauma, diagnose and stage cancer, monitor response ...

  13. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... bear denotes child-specific content. Related Articles and Media Radiation Dose in X-Ray and CT Exams ... or your insurance provider to get a better understanding of the possible charges you will incur. Web ...

  14. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... pictures of the inside of the body. The cross-sectional images generated during a CT scan can ... slices of the body, to create two-dimensional cross-sectional images, which are then displayed on a ...

  15. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... slices. When the image slices are reassembled by computer software, the result is a very detailed multidimensional view of the body's interior. Refinements in detector technology allow new CT scanners to obtain multiple slices ...

  16. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... to help diagnose abdominal pain or evaluate for injury after trauma. Tell your doctor about your child’s ... diagnose a wide range of conditions due to injury or illness. In children, CT is typically used ...

  17. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... radiation children may receive from a CT scan. One of the best ways of limiting radiation exposure ... or pediatrician and the radiologist will decide which type of examination is best for your child. top ...

  18. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... on photographic film or a special image recording plate . Bones appear white on the x-ray; soft ... will hear only slight buzzing, clicking and whirring sounds as the CT scanner revolves around him/her ...

  19. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... bear denotes child-specific content. Related Articles and Media Radiation Dose in X-Ray and CT Exams Contrast Materials Anesthesia Safety Children and Radiation Safety Images ...

  20. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... images and send an official report to your primary care physician or physician who referred you for the ... those obtained by CT scanning. Working together, your primary care physician or pediatrician and the radiologist will decide ...

  1. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... of the body, in a shorter period of time. Modern CT scanners are so fast that they can scan through large sections of the body in just a few seconds. Such speed is beneficial for ...

  2. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... a CT or CAT scan, is a diagnostic medical test that, like traditional x-rays, produces multiple ... your doctor of any recent illnesses or other medical conditions your child may have, and if there ...

  3. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... The teddy bear denotes child-specific content. Related Articles and Media Radiation Dose in X-Ray and CT ... note RadiologyInfo.org is not a medical facility. Please contact your physician with specific medical ...

  4. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... Sometimes ultrasound is substituted for CT as a method of imaging in these procedures in children. A ... 450 pounds—for the moving table. Other imaging methods such as ultrasound or magnetic resonance (MR) imaging ...

  5. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... over time. top of page What are the benefits vs. risks? Benefits Using a multidetector CT unit to examine children ... that will provide the needed diagnostic information. The benefit of an accurate diagnosis far outweighs the risk. ...

  6. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... as pneumonia a tumor that arises in the lung or has spread there from a distant site ... passages) birth defects trauma to blood vessels or lung CT is well-suited for visualizing diseases or ...

  7. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... children. top of page What are some common uses of the procedure? CT is used to help ... is done because a potential abnormality needs further evaluation with additional views or a special imaging technique. ...

  8. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... is the procedure performed? The technologist begins by positioning the patient on the CT examination table, usually ... encourage your child to report any discomfort during positioning because it is important to keep very still ...

  9. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... easier for children to hold their breath during critical parts of the exam. CT scanning is painless, ... the possible charges you will incur. Web page review process: This Web page is reviewed regularly by ...

  10. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... problems. Any of these conditions may influence the decision on whether contrast material will be given to ... unlike MRI. CT imaging provides real-time imaging, making it a good tool for guiding minimally invasive ...

  11. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... benefits vs. risks? Benefits Using a multidetector CT unit to examine children is faster than the older ... clearly needed. Another strategy is to consider other tests, such as MRI or ultrasound which might give ...

  12. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... create detailed images of your child’s internal organs, bones, soft tissues and blood vessels. It may be ... CD or DVD. CT images of internal organs, bones, soft tissue and blood vessels provide greater detail ...

  13. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... lives. CT has been shown to be a cost-effective imaging tool for a wide range of ... accredited facilities database . This website does not provide cost information. The costs for specific medical imaging tests, ...

  14. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... scanner. top of page How does the procedure work? In many ways, CT scanning is like other ... when the IV is inserted, usually into the hand or arm. The child may have a warm, ...

  15. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... read. top of page What will my child experience during and after the procedure? CT exams are ... scanning itself causes no pain, your child may experience some discomfort from having to remain still for ...

  16. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... is done because a potential abnormality needs further evaluation with additional views or a special imaging technique. ... CT scans that are not clearly needed. Another strategy is to consider other tests, such as MRI ...

  17. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... In children, CT is typically used to diagnose causes of abdominal pain, evaluate for injury after trauma, ... lie still is reduced. Though the scanning itself causes no pain, your child may experience some discomfort ...

  18. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... be necessary. Your doctor will explain the exact reason why another exam is requested. Sometimes a follow- ... fine tune" the CT settings based on the reason for the exam, the body area being examined, ...

  19. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... the x-rays in varying degrees. In a conventional x-ray exam, a small burst of radiation ... blood vessels all at the same time. Unlike conventional x-rays, CT scanning provides very detailed images ...

  20. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... it is possible, every effort is made to limit the amount of radiation children may receive from ... CT scanner or may be over the weight limit—usually 450 pounds—for the moving table. Other ...

  1. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... scanner. top of page How does the procedure work? In many ways, CT scanning is like other ... accurate diagnosis far outweighs the risk. See the Safety page for more information about radiation dose. There ...

  2. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... or thyroid problems. Any of these conditions may influence the decision on whether contrast material will be ... in CT scans should have no immediate side effects. Risks The risk of serious allergic reaction to ...

  3. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... like? The CT scanner is typically a large machine with a hole, or short tunnel, in the ... of this tunnel. In the center of the machine, the x-ray tube and electronic x-ray ...

  4. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... view of the body's interior. Refinements in detector technology allow new CT scanners to obtain multiple slices ... the technologist determines that the images are of high enough quality for the radiologist to read. top ...

  5. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... her during the imaging process. The technologist will leave the room to perform the CT scan. However, ... are sometimes the best way to see if treatment is working or if a finding is stable ...

  6. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... abdominal tumors or birth defects In the pelvic region, CT scans can help: detect cysts or tumors ... tests, treatments and procedures may vary by geographic region. Discuss the fees associated with your prescribed procedure ...

  7. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... scanner. top of page How does the procedure work? In many ways, CT scanning is like other ... stay in the exam room until your child has fallen asleep. There may be a somewhat longer ...

  8. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... scanning is painless, noninvasive and accurate. A major advantage of CT is its ability to image bone, ... us improve RadiologyInfo.org by taking our brief survey: Survey Do you have a personal story about ...

  9. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... heart disease, asthma, diabetes, kidney disease or thyroid problems. Any of these conditions may influence the decision ... imaging tool for a wide range of clinical problems. CT is less sensitive to patient movement than ...

  10. Quality assurance of computed tomography (CT) scanners

    International Nuclear Information System (INIS)

    Sankaran, A.; Sanu, K.K. . Email : a_sankaran@vsnl.com

    2004-01-01

    This article reviews the present status of research work and development of various test objects, phantoms and detector/instrumentation systems for quality assurance (QA) of computed tomography (CT) scanners, carried out in advanced countries, with emphasis on similar work done in this research centre. CT scanner is a complex equipment and routine quality control procedures are essential to the maintenance of image quality with optimum patient dose. Image quality can be ensured only through correlation between prospective monitoring of system components and tests of overall performance with standard phantoms. CT examinations contribute a large share to the population dose in advanced countries. The unique dosimetry problems in CT necessitate special techniques. This article describes a comprehensive kit developed indigenously for the following QA and type approval tests as well as for research studies on image quality/dosimetry on CT scanners

  11. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed ...

  12. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... a gown. You may be instructed to withhold food or drink beforehand, especially if sedation or anesthesia is to be used. In general, children who have recently been ill will not be sedated or anesthetized. What is Children's CT? What are some common uses ...

  13. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... images of your child’s internal organs, bones, soft tissues and blood vessels. It may be used to help diagnose ... DVD. CT images of internal organs, bones, soft tissue and blood vessels provide greater detail than traditional x-rays, ...

  14. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... if there is a history of heart disease, asthma, diabetes, kidney disease or thyroid problems. Any of these conditions may influence the decision on whether contrast material will be given to your child for the CT examination. top of page What ...

  15. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician ... CT or CAT scan, is a diagnostic medical test that, like traditional x-rays, produces multiple images ...

  16. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... the exam if your child has a known allergy to contrast material. Your child should wear loose, comfortable clothing and may be ... the time of the CT examination. If your child has a known contrast material allergy, you should inform the doctor and technologist prior ...

  17. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... there is a history of heart disease, asthma, diabetes, kidney disease or thyroid problems. Any of these conditions may influence the decision on whether contrast material will be given to your child for the CT examination. top of page What ...

  18. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... wide range of conditions due to injury or illness. In children, CT is typically used to diagnose causes of abdominal pain, evaluate for injury after trauma, diagnose and stage cancer, monitor response to treatment for cancer, and diagnose and monitor infectious or ...

  19. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... read. top of page What will my child experience during and after the procedure? CT exams are ... areas. Outside links: For the convenience of our users, RadiologyInfo .org provides links to relevant websites. RadiologyInfo. ...

  20. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... conventional CT scanner or may be over the weight limit—usually 450 pounds—for the moving table. Other imaging methods such as ultrasound or magnetic resonance (MR) imaging can provide pictures of certain areas of the body that sometimes are as good as or better ...

  1. [(18)F]Fluorodeoxyglucose - positron emission tomography/computed tomography improves staging in patients with high-risk muscle-invasive bladder cancer scheduled for radical cystectomy.

    Science.gov (United States)

    Kollberg, Petter; Almquist, Helen; Bläckberg, Mats; Cronberg, Carin; Garpered, Sabine; Gudjonsson, Sigurdur; Kleist, Jakob; Lyttkens, Kerstin; Patschan, Oliver; Liedberg, Fredrik

    2015-01-01

    The aim of this study was to evaluate the clinical use of [(18)F]fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) in addition to conventional preoperative radiological investigations in a defined group of patients with high-risk muscle-invasive bladder cancer. In total, 103 patients with high-risk muscle-invasive bladder cancer defined as stage T3/T4 disease or as stage T2 with hydronephrosis or high-risk histological features, who were provisionally scheduled to undergo cystectomy, were prospectively recruited to the study. The patients were referred to FDG-PET/CT in addition to standard preoperative investigation with computed tomography (CT). The final treatment decision was reached at a multidisciplinary conference based on all available information including the FDG-PET/CT findings. Compared to CT alone, FDG-PET/CT provided more supplemental findings suggesting malignant manifestations in 48 (47%) of the 103 patients. The additional FDG-PET/CT findings led to an altered provisional treatment plan in 28 out of 103 patients (27%), detection of disseminated bladder cancer and subsequent cancellation of the initially intended cystectomy in 16 patients, and identification of disseminated disease and treatment with induction chemotherapy before radical cystectomy in 12 patients. Preoperative FDG-PET/CT changed the treatment plan for a considerable proportion (27%) of the present patients. Accordingly, such examination can potentially improve the preoperative staging of cystectomy patients with high-risk features, and may also reduce the number of futile operations in patients with advanced disease who are beyond cure.

  2. Modeling correlation indices between bladder and Foley′s catheter balloon dose with CT-based planning using limited CT slices in intracavitary brachytherapy for carcinoma of cervix

    Directory of Open Access Journals (Sweden)

    Oinam Arun

    2008-01-01

    Full Text Available Purpose: To derive and validate an index to correlate the bladder dose with the catheter balloon dose using limited computed tomography (CT slices. Materials and Methods: Applicator geometry reconstructed from orthogonal radiographs were back-projected on CT images of the same patients for anatomy-based dosimetric evaluation. The correlation indices derived using power function of the catheter balloon dose and the bladder volume dose were validated in 31 patients with cervical cancer. Results: There was significant correlation between International Commission on Radiation Units (ICRU-38 balloon reference dose (Dr and the dose received by 25% bladder volume (D 25 (P < 0.0001. Significant correlation was also found between the reference dose of mid-balloon point (D rm and the dose to D 25 (P < 0.0001. Average percentage difference [100 x (observed index - expected index / expected index] of observed value of I′ 25 (index for the dose to D25 bladder with respect to mid-balloon reference point from that of expected value was 0.52%, when the index was modeled with reference dose alone. Similarly the average percentage difference for I′10cc (index for the dose to 10 cc volume of bladder with respect to mid balloon point was 0.84%. When this index was modeled with absolute bladder volume and reference dose, standard deviation of the percentage difference between observed and expected index for D rm reduced by approximately 2% when compared to D r . Conclusion: For clinical applications, correlation index modeled with reference dose and volume predicts dose to absolute volume of bladder. Correlation index modeled with reference dose gives a good estimate of dose to relative bladder volume. From our study, we found D rm to be a better indicator of bladder dose than D r .

  3. Comparison of ultrasound and computed tomography in staging of bladder cancer

    International Nuclear Information System (INIS)

    Suyama, Bunzo

    1982-01-01

    Preoperative staging of bladder cancer is very important for decision of treating methods and prognostication. The present author used ultrasound via the abdominal wall in the diagnosis of 83 patients with bladder cancer. I estimated the extent of bladder tumor infiltration by ultrasound via the abdominal wall according to Shiraishi's criteria. Ultrasound scans, pelvic angiograms and CT scans were reviewed to determine their accuracy in staging of bladder tumors. Ultrasound scans were excellent in staging of non-infiltrated bladder tumors, while pelvic angiograms and CT scans were excellent in staging of infiltrated bladder tumors. (author)

  4. Automatic bladder segmentation from CT images using deep CNN and 3D fully connected CRF-RNN.

    Science.gov (United States)

    Xu, Xuanang; Zhou, Fugen; Liu, Bo

    2018-03-19

    Automatic approach for bladder segmentation from computed tomography (CT) images is highly desirable in clinical practice. It is a challenging task since the bladder usually suffers large variations of appearance and low soft-tissue contrast in CT images. In this study, we present a deep learning-based approach which involves a convolutional neural network (CNN) and a 3D fully connected conditional random fields recurrent neural network (CRF-RNN) to perform accurate bladder segmentation. We also propose a novel preprocessing method, called dual-channel preprocessing, to further advance the segmentation performance of our approach. The presented approach works as following: first, we apply our proposed preprocessing method on the input CT image and obtain a dual-channel image which consists of the CT image and an enhanced bladder density map. Second, we exploit a CNN to predict a coarse voxel-wise bladder score map on this dual-channel image. Finally, a 3D fully connected CRF-RNN refines the coarse bladder score map and produce final fine-localized segmentation result. We compare our approach to the state-of-the-art V-net on a clinical dataset. Results show that our approach achieves superior segmentation accuracy, outperforming the V-net by a significant margin. The Dice Similarity Coefficient of our approach (92.24%) is 8.12% higher than that of the V-net. Moreover, the bladder probability maps performed by our approach present sharper boundaries and more accurate localizations compared with that of the V-net. Our approach achieves higher segmentation accuracy than the state-of-the-art method on clinical data. Both the dual-channel processing and the 3D fully connected CRF-RNN contribute to this improvement. The united deep network composed of the CNN and 3D CRF-RNN also outperforms a system where the CRF model acts as a post-processing method disconnected from the CNN.

  5. The value of computed tomography in the management of bladder cancer

    International Nuclear Information System (INIS)

    Karrer, P.; Zingg, E.; Vock, P.; Fischedick, A.; Haertel, M.; Fuchs, W.A.; Bern Univ.

    1980-01-01

    In 77 patients suffering from bladder cancer histopathological staging and CT-staging are compared. The invasion of bladder and lymph nodes by the tumor is confirmed by histological examination. The CT-results correspond with the pathological findings in 78% for the primary tumor and in 89% for the glands. CT is valuable help to establish the extent and staging of bladder tumors. (orig.) [de

  6. PET/CT in kidney and bladder cancer

    International Nuclear Information System (INIS)

    Bochev, P.; Klisarova, A.

    2013-01-01

    Full text: FDG PET/CT has traditionally been considered a method of limited use in tumors of the kidneys and excretory system. Major shortcoming of the method in kidney cancer is considered variable fixation and a more general lack of significant therapeutic alternatives that require early diagnosis of recurrence after nephrectomy. In the context of the modern methods of systemic anticancer therapy in kidney cancer, marking a significant success in terms of time to progression, the need of more detailed selection of the patients and the search methods for the early diagnosis and assessment of therapeutic response arises. While CT remains the primary method for the diagnosis of parenchymal metastases (lung, liver), the use of FDG PET/CT has a significant advantage in detecting of nodal metastasis, locoregional recurrence and bone metastasis. Interesting direction in the use of PET/CT remains the monitoring of therapeutic response to systemic therapy of metastatic kidney cancer. Unlike kidney cancer in transitional cell carcinoma of bladder (TCC), the application of FDG PET/CT is non- systematic and based on the specific clinical indications. As the main indicator can be observed the distant staging in locally advanced tumors and recurrences in restading after cystectomy. Besides the general advantages of PET/CT in terms of nodal and peritoneal involvement it should be noted that the role of the PET/CT in TCC is discussible. Application of FDG PET / CT in kidney cancer and TCC at this stage can not be considered as established, but while in TCCs, the method has sporadically application, mostly for specific clinical questions, the application in kidney cancer is significantly more systemic and in the context of systemic anti-tumor therapy allows early diagnosis and therapeutic approach modulation

  7. Role of computed tomography (CT scan in staging of cervical carcinoma

    Directory of Open Access Journals (Sweden)

    T V Prasad

    2014-01-01

    Full Text Available Background & objectives: Staging of cervical carcinoma is done clinically using International Federation of Obstetrics and Gynecology (FIGO guidelines. It is based on physical examination findings and also includes results of biopsy, endoscopy and conventional radiological tests like chest radiograph, intravenous urography and barium enema. These conventional radiological investigations have largely been replaced by computed tomography (CT and magnetic resonance imaging (MRI at present. FIGO staging system does not consider CT and MRI mandatory; however, use of these modalities are encouraged. This prospective study was conducted to determine the role of CT in staging work up in women diagnosed with cervical carcinoma. Methods: Fifty three women diagnosed with cervical carcinoma were evaluated with contrast enhanced CT scan of abdomen and pelvis. CT scan images were especially evaluated to determine tumour size, invasion of parmetrium, pelvic walls, rectum, urinary bladder and ureters, pelvic or retroperitoneal lymphadenopathy and distant metastases. CT findings were associated with clinical findings and staging, including findings from cystoscopy and sigmoidoscopy. Results: There was a poor agreement between clinical and CT staging of cervical carcinoma. Primary tumour was demonstrated on CT in 36 (70% of 53 patients. CT underestimated the parametrial, vaginal and pelvic wall invasion when compared with physical examination. CT overestimated the urinary bladder and rectal invasion when compared with cysto-sigmoidoscopy, however, CT had 100 per cent negative predictive value (NPV to exclude bladder and rectal involvement. CT detection of lymph node enlargement and lung metastases influenced the management. Interpretation & conclusions: Our findings show that CT scan does not reliably correlate with clinical FIGO staging of cervical cancer. However, it can detect urinary obstruction as well as nodal or distant metastases and thus improves the

  8. Intra-diverticular bladder cancer: CT imaging features and their association with clinical outcomes

    Science.gov (United States)

    Di Paolo, Pier Luigi; Vargas, Hebert Alberto; Karlo, Christoph A.; Lakhman, Yulia; Zheng, Junting; Moskowitz, Chaya S.; Al-Ahmadie, Hikmat A.; Sala, Evis; Bochner, Bernard H.; Hricak, Hedvig

    2014-01-01

    Objectives evaluate if CT features of intra-diverticular bladder cancer can predict clinical outcome. Methods retrospective study of 34 patients with intra-diverticular bladder cancer. Two radiologists independently evaluated all CT exams. Results CT tumor length and width were significantly associated with survival for both readers (HRs 1.31–1.62, ppathology stage and survival (HR 2.10; p=0.21). Conclusions In patients with intra-diverticular bladder cancer, the tumor length and width measured on the pre-treatment CT predicted survival. PMID:25457532

  9. Lymphography and computed tomography in the assessment of lymphnode invasion by bladder cancer. Comparison of diagnostic value

    International Nuclear Information System (INIS)

    Leguay, O.; Bellin, M.F.; Richard, F.; Mallet, A.; Grellet, J.

    1989-01-01

    The diagnostic value of lymphography and computed tomography (CT) in the assessment of lymph node invasion by bladder cancers has been compared on the basis of 30 observations. Although computed tomography apparently yields better results (reliability: 93%) than lymphography (reliability: 87%), these findings have no statistical significance. The study of literature shows that the statistical exploitation of the results was seldom carried out. The combination of both exploration techniques seems to improve predictive values, but this improvement was not statistically significant in the study [fr

  10. Accuracy of preoperative urinary symptoms, urinalysis, computed tomography and cystoscopic findings for the diagnosis of urinary bladder invasion in patients with colorectal cancer.

    Science.gov (United States)

    Woranisarakul, Varat; Ramart, Patkawat; Phinthusophon, Kittipong; Chotikawanich, Ekkarin; Prapasrivorakul, Siriluck; Lohsiriwat, Varut

    2014-01-01

    To determine the accuracy of preoperative urinary symptoms, urinalysis, computed tomography (CT) and cystoscopic findings for the diagnosis of urinary bladder invasion in patients with colorectal cancer. Records of patients with colorectal cancer and a suspicion of bladder invasion, who underwent tumor resection with partial or total cystectomy between 2002 and 2013 at the Faculty of Medicine Siriraj Hospital, were reviewed. Correlations between preoperative urinary symptoms, urinalysis, cystoscopic finding, CT imaging and final pathological reports were analyzed. This study included 90 eligible cases (71% male). The most common site of primary colorectal cancer was the sigmoid colon (44%), followed by the rectum (33%). Final pathological reports showed definite bladder invasion in 53 cases (59%). Significant features for predicting definite tumor invasion were gross hematuria (OR 13.6, sensitivity 39%, specificity 73%), and visible tumor during cystoscopy (OR 5.33, sensitivity 50%, specificity 84%). Predictive signs in CT imaging were gross tumor invasion (OR 7.07, sensitivity 89%, specificity 46%), abnormal enhancing mass at bladder wall (OR 4.09, sensitivity 68%, specificity 66%), irregular bladder mucosa (OR 3.53, sensitivity 70%, specificity 60% ), and loss of perivesical fat plane (OR 3.17, sensitivity 81%, specificity 43%). However, urinary analysis and other urinary tract symptoms were poor predictors of bladder involvement. The present study demonstrated that the most relevant preoperative predictors of definite bladder invasion in patients with colorectal cancer are gross hematuria, a visible tumor during cystoscopy, and abnormal CT findings.

  11. Pelvic CT scan

    Science.gov (United States)

    CAT scan - pelvis; Computed axial tomography scan - pelvis; Computed tomography scan - pelvis; CT scan - pelvis ... Abnormal results may be due to: Abscess (collection of pus) Bladder stones Broken bone Cancer Diverticulitis

  12. Multidetector CT cystography for imaging colovesical fistulas and iatrogenic bladder leaks

    OpenAIRE

    Tonolini, Massimo; Bianco, Roberto

    2012-01-01

    Multidetector computed tomography (MDCT) cystography currently represents the modality of choice to image the urinary bladder in traumatized patients. In this review we present our experience with MDCT cystography applications outside the trauma setting, particularly for diagnosing bladder fistulas and leaks. A detailed explanation is provided concerning exam preparation, acquisition technique, image reconstruction and interpretation. Colovesical fistulas most commonly occur as a complication...

  13. Evaluation of dosimetric techniques in positrons emission tomography and computerized tomography (PET/CT)

    International Nuclear Information System (INIS)

    Pinto, Gabriella Montezano

    2014-01-01

    Among diagnostic techniques PET/CT is one of those with the highest dose delivery to the patient as a cause of external exposure to X-rays, and the use of a radiopharmaceutical that results in a high energy gamma emission. The dosimetry of these two components becomes important in order to optimize and justify the technique. Various dosimetric techniques are found in literature without a consensus of the best to use. With the advances in technological and consequent equipment configuration changes, upgrades and variation in methodologies, particularly in computed tomography, a standardization of these techniques is required. Previous studies show that CT is responsible for 70 % of the dose delivered to the patient in PET/CT examinations. Thus, many researchers have been focused on CT dose optimization protocols studies. This work analyzes the doses involved in a PET/CT oncology protocol by using an Alderson female anthropomorphic phantom in a public hospital of Rio de Janeiro city. The dose estimate for PET examination resulting from the use of 18 F - FDG radiopharmaceutical was conducted through dose factors published in ICRP 106; the dose for CT was estimated and compared by calculation of the absorbed doses to patients according to four methods: thermoluminescent dosimetry (TL0100) distributed in critical organs of the Alderson phantom; measurements of CTOI according to AAPM number 96; correction factor for effective diameter SSOE (AAPM Number 204); and simulation by ImPACT program For CT, the results in terms of effective dose presented (TLO, CTOI and ImPACT) ± 5 % maximum variations between methodologies. Considering medium absorbed dose (TLO, SSOE and ImPACT) the results differed in ± 7 % from each other. These findings demonstrate that parameters provided by the manufacturer on the console can be used to have a primary approach of both, absorbed and effective doses to the patient since that a quality assurance program of these parameters are adopted in

  14. Fusion of planning CT and cystoscopy images for bladder tumor delineation: a feasibility study

    NARCIS (Netherlands)

    Dees-Ribbers, Hermine M.; Pos, Floris J.; Betgen, Anja; Bex, Axel; Hulshof, Maarten C. C. M.; Remeijer, Peter; van Herk, Marcel

    2013-01-01

    Bladder tumor delineation and localization during treatment are challenging problems in radiotherapy for bladder cancer. The purpose of this study is to investigate improvement of tumor delineation by the fusion of cystoscopy images with the planning CT-scan using lipiodol markers injected around

  15. Diuretic 18F-FDG PET/CT imaging for detection and locoregional staging of urinary bladder cancer: prospective evaluation of a novel technique

    International Nuclear Information System (INIS)

    Nayak, Brusabhanu; Dogra, Prem Nath; Naswa, Niraj; Kumar, Rakesh

    2013-01-01

    Positron emission tomography/computed tomography (PET/CT) with 18 F-fluorodeoxyglucose (FDG) has been used with limited success in the past in primary diagnosis and locoregional staging of urinary bladder cancer, mainly because of the pharmacokinetics of renal excretion of 18 F-FDG. In the present prospective study, we have evaluated the potential application of diuretic 18 F-FDG PET/CT in improving detection and locoregional staging of urinary bladder tumours. Twenty-five patients suspected of having primary carcinoma of the urinary bladder were evaluated prospectively for diagnosis and staging. All of these 25 patients underwent conventional contrast-enhanced computed tomography (CECT) of the abdomen/pelvis and whole-body diuretic 18 F-FDG PET/CT. In addition, pelvic PET/CT images were obtained using the special technique of forced diuresis using intravenous furosemide (20-40 mg). Of the 25 patients, 10 underwent radical cystectomy and 15 underwent transurethral resection of the bladder tumour (TURBT). Results of CECT and diuretic 18 F-FDG PET/CT were compared considering histopathology as a reference standard. Of the 25 patients, CECT detected a primary tumour in 23 (sensitivity 92 %), while 18 F-FDG PET/CT was positive in 24 patients (sensitivity 96 %). Mean size and maximum standardized uptake value of the bladder tumours were 3.33 cm (range 1.6-6.2) and 5.3 (range 1.3-11.7), respectively. Of the 25 patients, only 10 patients underwent radical cystectomy based on disease status on TURBT. Among those ten patients, nine had locoregional metastases. Among the nine patients who had positive lymph nodes for metastasis on histopathology, CECT and PET/CT scan had a sensitivity of 44 and 78 %, respectively. 18 F-FDG PET/CT was found to be superior to CECT in the detection of the primary tumour and locoregional staging (p 18 F-FDG PET/CT is highly sensitive and specific and plays an important role in improving detection of the primary tumour and locoregional staging of

  16. Diuretic {sup 18}F-FDG PET/CT imaging for detection and locoregional staging of urinary bladder cancer: prospective evaluation of a novel technique

    Energy Technology Data Exchange (ETDEWEB)

    Nayak, Brusabhanu; Dogra, Prem Nath [All India Institute of Medical Sciences, Department of Urology, New Delhi (India); Naswa, Niraj [All India Institute of Medical Sciences, Department of Nuclear Medicine, New Delhi (India); Kumar, Rakesh [All India Institute of Medical Sciences, Department of Nuclear Medicine, New Delhi (India); New Delhi (India)

    2013-03-15

    Positron emission tomography/computed tomography (PET/CT) with {sup 18}F-fluorodeoxyglucose (FDG) has been used with limited success in the past in primary diagnosis and locoregional staging of urinary bladder cancer, mainly because of the pharmacokinetics of renal excretion of {sup 18}F-FDG. In the present prospective study, we have evaluated the potential application of diuretic {sup 18}F-FDG PET/CT in improving detection and locoregional staging of urinary bladder tumours. Twenty-five patients suspected of having primary carcinoma of the urinary bladder were evaluated prospectively for diagnosis and staging. All of these 25 patients underwent conventional contrast-enhanced computed tomography (CECT) of the abdomen/pelvis and whole-body diuretic {sup 18}F-FDG PET/CT. In addition, pelvic PET/CT images were obtained using the special technique of forced diuresis using intravenous furosemide (20-40 mg). Of the 25 patients, 10 underwent radical cystectomy and 15 underwent transurethral resection of the bladder tumour (TURBT). Results of CECT and diuretic {sup 18}F-FDG PET/CT were compared considering histopathology as a reference standard. Of the 25 patients, CECT detected a primary tumour in 23 (sensitivity 92 %), while {sup 18}F-FDG PET/CT was positive in 24 patients (sensitivity 96 %). Mean size and maximum standardized uptake value of the bladder tumours were 3.33 cm (range 1.6-6.2) and 5.3 (range 1.3-11.7), respectively. Of the 25 patients, only 10 patients underwent radical cystectomy based on disease status on TURBT. Among those ten patients, nine had locoregional metastases. Among the nine patients who had positive lymph nodes for metastasis on histopathology, CECT and PET/CT scan had a sensitivity of 44 and 78 %, respectively. {sup 18}F-FDG PET/CT was found to be superior to CECT in the detection of the primary tumour and locoregional staging (p < 0.05). Diuretic {sup 18}F-FDG PET/CT is highly sensitive and specific and plays an important role in improving

  17. Characterization of dynamic physiology of the bladder by optical coherence tomography

    Science.gov (United States)

    Yuan, Zhijia; Keng, Kerri; Pan, Rubin; Ren, Hugang; Du, Congwu; Kim, Jason; Pan, Yingtian

    2012-03-01

    Because of its high spatial resolution and noninvasive imaging capabilities, optical coherence tomography has been used to characterize the morphological details of various biological tissues including urinary bladder and to diagnose their alternations (e.g., cancers). In addition to static morphology, the dynamic features of tissue morphology can provide important information that can be used to diagnose the physiological and functional characteristics of biological tissues. Here, we present the imaging studies based on optical coherence tomography to characterize motion related physiology and functions of rat bladder detrusor muscles and compared the results with traditional biomechanical measurements. Our results suggest that optical coherence tomography is capable of providing quantitative evaluation of contractile functions of intact bladder (without removing bladder epithelium and connective tissue), which is potentially of more clinical relevance for future clinical diagnosis - if incorporated with cystoscopic optical coherence tomography.

  18. Segmentation of urinary bladder in CT Urography (CTU) using CLASS

    Science.gov (United States)

    Hadjiiski, Lubomir; Chan, Heang-Ping; Law, Yuen; Cohan, Richard H.; Caoili, Elaine M.; Cho, Hyun-Chong; Zhou, Chuan; Wei, Jun

    2012-03-01

    We are developing a computerized system for bladder segmentation on CTU, as a critical component for computer aided diagnosis of bladder cancer. A challenge for bladder segmentation is the presence of regions without contrast (NC) and filled with IV contrast (C). We are developing a Conjoint Level set Analysis and Segmentation System (CLASS) specifically for this application. CLASS performs a series of image processing tasks: preprocessing, initial segmentation, and 3D and 2D level set segmentation and post-processing, designed according to the characteristics of the bladder in CTU. The NC and the C regions of the bladder were segmented separately in CLASS. The final contour is obtained in the post-processing stage by the union of the NC and C contours. Seventy bladders (31 containing lesions, 24 containing wall thickening, and 15 normal) were segmented. The performance of CLASS was assessed by rating the quality of the contours on a 5-point scale (1= "very poor", 3= "fair", 5 = "excellent"). For the 53 partially contrast-filled bladders, the average quality ratings for the 53 NC and 53 C regions were 4.0+/-0.7 and 4.0+/-1.0, respectively. 46 NC and 41 C regions were given quality ratings of 4 or above. Only 2 NC and 5 C regions had ratings under 3. The average quality ratings for the remaining 12 completely no contrast (NC) and 5 completely contrast-filled (C) bladder contours were 3.3+/-1.0 and 3.4+/-0.5, respectively. After combining the NC and C contours for each of the 70 bladders, 46 had quality ratings of 4 or above. Only 4 had ratings under 3. The average quality rating was 3.8+/-0.7. The results demonstrate the potential of CLASS for automated segmentation of the bladder.

  19. The accuracy of after-hour registrar computed tomography (CT ...

    African Journals Online (AJOL)

    2014-05-16

    May 16, 2014 ... tomography (CT) reporting in a South African tertiary teaching hospital. Authors: ... The purpose of this study was to determine the accuracy of after-hour registrar CT reporting, to identify possible factors that may .... The authors declare that they have no financial or personal relationship(s) that may have ...

  20. NONINVASIVE DIAGNOSIS OF BLADDER CANCER BY CROSS-POLARIZATION OPTICAL COHERENCE TOMOGRAPHY: A BLIND STATISTICAL STUDY

    Directory of Open Access Journals (Sweden)

    O. S. Streltsova

    2014-07-01

    Full Text Available Whether cross-polarization (CP optical coherence tomography (OCT could be used to detect early bladder cancer was ascertained; it was compared with traditional OCT within the framework of blind (closed clinical statistical studies. One hundred and sixteen patients with local nonexophytic (flat pathological processes of the bladder were examined; 360 CP OCT images were obtained and analyzed. The study used an OCT 1300-U CP optical coherence tomographer. CP OCT showed a high (94% sensitivity and a high (84% specificity in the identification of suspected nonexophytic areas in the urinary bladder.

  1. Fundamental study of computed tomography (CT), 5

    International Nuclear Information System (INIS)

    Katakura, Toshihiko; Kimura, Kazue; Suzuki, Kenji; Ito, Masami; Okuaki, Koji

    1980-01-01

    Discussion was made on errors when the size of objects were measured on CT images, comparing among various measurement methods. The measured object was an acryl pipe of 47.95 mm in external diameter and 27.65 mm in internal diameter, in which water and alchol were stuffed. CT scanning of this acryl pipe was performed at 90 0 , 60 0 , and 30 0 of angles between an acryl pipe and CT slice plane, and the size of this pipe was measured on CT images by three methods, (1) CT values profile, (2) recognition of multiformat images, and (3) enhancement curves of multiformat images. CT images were taken in slice thickness of 14 and 17 mm. As a result, No. 1 method was the best. When slice thickness was thin, measurement errors were small, even on CT images taken at small angles to the slice plane. When the size of the object was measured on multiformat images, it was better to take CT images at window level with intermediate CT values between two adjacent objects. In case of measurement by recognition, measurement errors became smallest when the size of object were measured on multiformat images with the smallest window width at the intermediate window level. Clinically, it was easy to use such a method that after measuring by many examiners on CT images taken with the widest window width at the most adequate possible window level, then average out the measured values. (J.P.N.)

  2. Estimation of kidneys and urinary bladder doses based on the region of interest in 18fluorine-fluorodeoxyglucose positron emission tomography/computed tomography examination: a preliminary study.

    Science.gov (United States)

    Mustapha, Farida Aimi; Bashah, Farahnaz Ahmad Anwar; Yassin, Ihsan M; Fathinul Fikri, Ahmad Saad; Nordin, Abdul Jalil; Abdul Razak, Hairil Rashmizal

    2017-06-01

    Kidneys and urinary bladder are common physiologic uptake sites of 18fluorine-fluorodeoxyglucose ( 18 F-FDG) causing increased exposure of low energy ionizing radiation to these organs. Accurate measurement of organ dose is vital as 18 F-FDG is directly exposed to the organs. Organ dose from 18 F-FDG PET is calculated according to the injected 18 F-FDG activity with the application of dose coefficients established by International Commission on Radiological Protection (ICRP). But this dose calculation technique is not directly measured from these organs; rather it is calculated based on total injected activity of radiotracer prior to scanning. This study estimated the 18 F-FDG dose to the kidneys and urinary bladder in whole body positron emission tomography/computed tomography (PET/CT) examination by comparing dose from total injected activity of 18 F-FDG (calculated dose) and dose from organs activity based on the region of interest (ROI) (measured dose). Nine subjects were injected intravenously with the mean 18 F-FDG dose of 292.42 MBq prior to whole body PET/CT scanning. Kidneys and urinary bladder doses were estimated by using two approaches which are the total injected activity of 18 F-FDG and organs activity concentration of 18 F-FDG based on drawn ROI with the application of recommended dose coefficients for 18 F-FDG described in the ICRP 80 and ICRP 106. The mean percentage difference between calculated dose and measured dose ranged from 98.95% to 99.29% for the kidneys based on ICRP 80 and 98.96% to 99.32% based on ICRP 106. Whilst, the mean percentage difference between calculated dose and measured dose was 97.08% and 97.27% for urinary bladder based on ICRP 80 while 96.99% and 97.28% based on ICRP 106. Whereas, the range of mean percentage difference between calculated and measured organ doses derived from ICRP 106 and ICRP 80 for kidney doses were from 17.00% to 40.00% and for urinary bladder dose was 18.46% to 18.75%. There is a significant

  3. Abdominal and Pelvic CT

    Medline Plus

    Full Text Available ... Radiation Therapy for Bladder Cancer Radiation Therapy for Colorectal Cancer top of page This page was reviewed on ... GI Tract X-ray (Radiography) - Upper GI Tract Colorectal Cancer Images related to Computed Tomography (CT) - Abdomen and ...

  4. Value of positron emission tomography and computer tomography (PET/CT) for urologic malignancies

    International Nuclear Information System (INIS)

    Boujelbene, N.; Mirimanoff, R.O.; Ozsahin, M.; Zouhair, A.; Prior, J.O.; Boubaker, A.; Azria, D.; Schaffer, M.; Gez, E.; Jichlinski, P.; Meuwly, J.Y.

    2011-01-01

    Positron emission tomography is a functional imaging technique that allows the detection of the regional metabolic rate, and is often coupled with other morphological imaging technique such as computed tomography. The rationale for its use is based on the clearly demonstrated fact that functional changes in tumor processes happen before morphological changes. Its introduction to the clinical practice added a new dimension in conventional imaging techniques. This review presents the current and proposed indications of the use of positron emission/computed tomography for prostate, bladder and testes, and the potential role of this exam in radiotherapy planning. (authors)

  5. Do Foley catheters adequately drain the bladder? Evidence from CT imaging studies

    Energy Technology Data Exchange (ETDEWEB)

    Avulova, Svetlana; Li, Valery J.; Khusid, Johnathan A. [Department of Urology, SUNY Downstate College of Medicine, Brooklyn, NY (United States); Choi, Woo S. [Radiology, SUNY Downstate College of Medicine, Brooklyn, NY (United States); Weiss, Jeffrey P., E-mail: johnathan.khusid@downstate.edu [Department of Urology, Weill Cornell Medical College, New York, NY (United States)

    2015-05-15

    Introduction: The Foley catheter has been widely assumed to be an effective means of draining the bladder. However, recent studies have brought into question its efficacy. The objective of our study is to further assess the adequacy of Foley catheter for complete drainage of the bladder. Materials and Methods: Consecutive catheterized patients were identified from a retrospective review of contrast enhanced and non-contrast enhanced computed tomographic (CT) abdomen and pelvis studies completed from 7/1/2011-6/30/2012. Residual urine volume (RUV) was measured using 5mm axial CT sections as follows: The length (L) and width (W) of the bladder in the section with the greatest cross sectional area was combined with bladder height (H) as determined by multiplanar reformatted images in order to calculate RUV by applying the formula for the volume (V) of a sphere in a cube:V=(π/6)⁎L⁎W⁎H). Results: RUVs of 167 (mean age 67) consecutively catheterized men (n=72) and women (n=95) identified by CT abdomen and pelvis studies were calculated. The mean RUV was 13.2 mL (range: 0.0 mL-859.1 mL, standard deviation: 75.9 mL, margin of error at 95% confidence:11.6 mL). Four (2.4%) catheterized patients had RUVs of >50 mL, two of whom had an improperly placed catheter tip noted on their CT-reports. Conclusions: Previous studies have shown that up to 43% of catheterized patients had a RUV greater than 50 mL, suggesting inadequacy of bladder drainage via the Foley catheter. Our study indicated that the vast majority of patients with Foley catheters (97.6%), had adequately drained bladders with volumes of <50 mL. (author)

  6. Automatic staging of bladder cancer on CT urography

    Science.gov (United States)

    Garapati, Sankeerth S.; Hadjiiski, Lubomir M.; Cha, Kenny H.; Chan, Heang-Ping; Caoili, Elaine M.; Cohan, Richard H.; Weizer, Alon; Alva, Ajjai; Paramagul, Chintana; Wei, Jun; Zhou, Chuan

    2016-03-01

    Correct staging of bladder cancer is crucial for the decision of neoadjuvant chemotherapy treatment and minimizing the risk of under- or over-treatment. Subjectivity and variability of clinicians in utilizing available diagnostic information may lead to inaccuracy in staging bladder cancer. An objective decision support system that merges the information in a predictive model based on statistical outcomes of previous cases and machine learning may assist clinicians in making more accurate and consistent staging assessments. In this study, we developed a preliminary method to stage bladder cancer. With IRB approval, 42 bladder cancer cases with CTU scans were collected from patient files. The cases were classified into two classes based on pathological stage T2, which is the decision threshold for neoadjuvant chemotherapy treatment (i.e. for stage >=T2) clinically. There were 21 cancers below stage T2 and 21 cancers at stage T2 or above. All 42 lesions were automatically segmented using our auto-initialized cascaded level sets (AI-CALS) method. Morphological features were extracted, which were selected and merged by linear discriminant analysis (LDA) classifier. A leave-one-case-out resampling scheme was used to train and test the classifier using the 42 lesions. The classification accuracy was quantified using the area under the ROC curve (Az). The average training Az was 0.97 and the test Az was 0.85. The classifier consistently selected the lesion volume, a gray level feature and a contrast feature. This predictive model shows promise for assisting in assessing the bladder cancer stage.

  7. Optical coherence tomography in diagnostics of precancer and cancer of human bladder

    Science.gov (United States)

    Zagaynova, Elena V.; Streltsova, Olga S.; Gladkova, Natalia D.; Shakhova, Natalia M.; Feldchtein, Felix I.; Kamensky, Vladislav A.; Gelikonov, Grigory V.; Snopova, Ludmila B.; Donchenko, Ekaterina V.

    2004-07-01

    Our goal was statistical assessment of the in vivo cystoscopic optical coherence tomography (OCT) ability to detect neoplasia in human urinary bladder. We analyzed major reasons of false positive and false negative image recognition results. Optical coherence tomography was performed to image the bladder during cystoscopy. The study enrolled 63 patients with suspicion for bladder cancer and scheduled for cystoscopy. The diagnosis was established by histopathology examination of a biopsy. Each biopsy site was examined by OCT. Benign conditions were diagnosed for 31 patients, and dysplasia or carcinoma were diagnosed for 32 patients. Six physicians blinded to all clinical data participated in the dichotomy recognition (malignant or benign) of the OCT images. 98% sensitivity and 72% specificity for the OCT recognition of dysplastic/malignant versus benign/reactive conditions of the bladder are demonstrated. Total error rate was 14.8%. The interobserver agreement multi-rater kappa coefficient is 0.80. The superficial and invasive bladder cancer and high-grade dysplasia were recognized with minimum error rate ranging from 0 to 3.3%. High sensitivity and good specificity of the OCT method in the diagnostics of bladder neoplasia makes OCT a promising complementary cystoscopic technique for non-invasive evaluation of zones suspicious for high-grade dysplasia and cancer.

  8. Computed tomography (CT) in neuromuscular disorders

    International Nuclear Information System (INIS)

    Novak, M.; Ambler, Z.

    1997-01-01

    For 24 patients with confirmed neuromuscular disorders, the clinical picture of the disease was complemented with CT examination. It is concluded, in accordance with the literature, that CT has a supplementary value as regards the extent and degree of disorder of the affected muscle groups. The basic pathological picture includes muscular atrophies, dystrophies, hypertrophies, and their combinations. The CT images are non-specific for the individual neuromuscular disorders and are of minor importance in the diagnostic process. 1 tab., 7 figs., 6 refs

  9. Thyroid lymphography-computed tomography (TLG-CT)

    International Nuclear Information System (INIS)

    Matsuyama, Koukichi

    1992-01-01

    There are several useful diagnostic examinations for thyroid disease. The diagnostic value of CT in thyroid disease is still controvertial, although CT has become a routine clinical examination, since the plain CT does not always identify tumors accurately. In this paper, we introduce for the first time thyroid lymphography-computed tomography (TLG-CT) which may improve the diagnostic value of CT. The technique combines CT with thyroid lymphography. We performed TLG-CT in 92 patients with various thyroid diseases and 20 normal controls and classified the radiological features into the following 6 types: entire (normal thyroid); moth-eaten (Hashimoto's thyroiditis); defect (follicular adenoma and adenomatous goiter); lobate (papillary carcinoma); localized (various thyroid diseases); and extrathyroid defect (parathyroid tumor). In addition, we examined the relationship between TLG-CT type and the macroscopic appearance of the cut surface of the thyroid and lymph node metastasis in 20 patients with papillary carcinoma. The results suggest that papillary TLG-CT type carcinomas have a high incidence of lymph node metastasis. Our preliminary results suggest that TLG-CT is a potentially valuable diagnostic tool in the detection of thyroid disease and the assessment of the pathologic diagnosis as well as lymph node metastasis. (author)

  10. Comparison of post contrast CT urography phases in bladder cancer detection

    Energy Technology Data Exchange (ETDEWEB)

    Helenius, Malin; Dahlman, Par; Lonnemark, Maria; Magnusson, Anders [Uppsala University Hospital, Department of Surgical Sciences, Section of Radiology, Uppsala (Sweden); Brekkan, Einar [Uppsala University Hospital, Department of Surgical Sciences, Section of Urology, Uppsala (Sweden); Wernroth, Lisa [Uppsala University Hospital, Uppsala Clinical Research Center, Uppsala (Sweden)

    2016-02-15

    The aim of this study was to investigate which post-contrast phase(s) in a four-phase CT urography protocol is (are) most suitable for bladder cancer detection. The medical records of 106 patients with visible haematuria who underwent a CT urography examination, including unenhanced, enhancement-triggered corticomedullary (CMP), nephrographic (NP) and excretory (EP) phases, were reviewed. The post-contrast phases (n = 318 different phases) were randomized into an evaluation order and blindly reviewed by two uroradiologists. Twenty-one patients were diagnosed with bladder cancer. Sensitivity for bladder cancer detection was 0.95 in CMP, 0.83 in NP and 0.81 in EP. Negative predictive value (NPV) was 0.99 in CMP, 0.96 in NP and 0.95 in EP. The sensitivity was higher in CMP than in both NP (p-value 0.016) and EP (p-value 0.0003). NPV was higher in CMP than in NP (p-value 0.024) and EP (p-value 0.002). In the CT urography protocol with enhancement-triggered scan, sensitivity and NPV were highest in the corticomedullary phase, and this phase should be used for bladder assessment. (orig.)

  11. Comparison of post contrast CT urography phases in bladder cancer detection

    International Nuclear Information System (INIS)

    Helenius, Malin; Dahlman, Par; Lonnemark, Maria; Magnusson, Anders; Brekkan, Einar; Wernroth, Lisa

    2016-01-01

    The aim of this study was to investigate which post-contrast phase(s) in a four-phase CT urography protocol is (are) most suitable for bladder cancer detection. The medical records of 106 patients with visible haematuria who underwent a CT urography examination, including unenhanced, enhancement-triggered corticomedullary (CMP), nephrographic (NP) and excretory (EP) phases, were reviewed. The post-contrast phases (n = 318 different phases) were randomized into an evaluation order and blindly reviewed by two uroradiologists. Twenty-one patients were diagnosed with bladder cancer. Sensitivity for bladder cancer detection was 0.95 in CMP, 0.83 in NP and 0.81 in EP. Negative predictive value (NPV) was 0.99 in CMP, 0.96 in NP and 0.95 in EP. The sensitivity was higher in CMP than in both NP (p-value 0.016) and EP (p-value 0.0003). NPV was higher in CMP than in NP (p-value 0.024) and EP (p-value 0.002). In the CT urography protocol with enhancement-triggered scan, sensitivity and NPV were highest in the corticomedullary phase, and this phase should be used for bladder assessment. (orig.)

  12. Computed tomography (CT) of skeletal muscle in neuromuscular disorders

    International Nuclear Information System (INIS)

    Nagao, Hideo; Morimoto, Takehiko; Takahashi, Mitsugi; Habara, Shinji; Nagai, Hironao; Matsuda, Hiroshi

    1987-01-01

    We investigated whether or not computerized tomography (CT) of skeletal muscle was of value for the diagnosis of neuromuscular disorders, through a comparison of CT findings in the skeletal muscle with histological findings in the muscle obtained by surgical biopsy. There were clear histological lesions even in cases in which low density areas were not seen on CT of the skeletal muscle. The muscle exhibiting remarkably low density areas showed high proliferation of the connective tissue and high accumulation of fat, but contained no muscle fibers. Therefore, the most suitable site for a biopsy was the muscle which exhibited mildly low density areas on CT. In floppy infants, the CT value was helpful for the diagnosis, even if low density areas did not appear because of remarkable muscle atrophy and monotonous lesions of the whole muscle. (author)

  13. Diagnostic reference level of computed tomography (CT) in Japan.

    Science.gov (United States)

    Fukushima, Yasuhiro; Tsushima, Yoshito; Takei, Hiroyuki; Taketomi-Takahashi, Ayako; Otake, Hidenori; Endo, Keigo

    2012-08-01

    Optimisation of computed tomography (CT) parameters is important in avoiding excess radiation exposure. The aim of this study is to establish the diagnostic reference levels (DRL) of CT in Japan by using dose-length product (DLP). Datasheets were sent to all hospitals/clinics which had CT scanner(s) in Gunma prefecture. Data were obtained for all patients who underwent CT during a single month (June 2010), and the distributions of DLP were evaluated for eight anatomical regions and five patient age groups. The DRL was defined as the 25th and 75th percentiles of DLP. Datasheets were collected from 80 of 192 hospitals/clinics (26 090 patients). DLP for head CT of paediatric patients tended to be higher in Japan compared with DRLs of paediatric head CTs reported from the EU or Syria. Although this study was performed with limited samples, DLP for adult patients were at comparable levels for all anatomical regions.

  14. Flat-detector computed tomography (FD-CT)

    International Nuclear Information System (INIS)

    Kalender, Willi A.; Kyriakou, Yiannis

    2007-01-01

    Flat-panel detectors or, synonymously, flat detectors (FDs) have been developed for use in radiography and fluoroscopy with the defined goal to replace standard X-ray film, film-screen combinations and image intensifiers by an advanced sensor system. FD technology in comparison to X-ray film and image intensifiers offers higher dynamic range, dose reduction, fast digital readout and the possibility for dynamic acquisitions of image series, yet keeping to a compact design. It appeared logical to employ FD designs also for computed tomography (CT) imaging. Respective efforts date back a few years only, but FD-CT has meanwhile become widely accepted for interventional and intra-operative imaging using C-arm systems. FD-CT provides a very efficient way of combining two-dimensional (2D) radiographic or fluoroscopic and 3D CT imaging. In addition, FD technology made its way into a number of dedicated CT scanner developments, such as scanners for the maxillo-facial region or for micro-CT applications. This review focuses on technical and performance issues of FD technology and its full range of applications for CT imaging. A comparison with standard clinical CT is of primary interest. It reveals that FD-CT provides higher spatial resolution, but encompasses a number of disadvantages, such as lower dose efficiency, smaller field of view and lower temporal resolution. FD-CT is not aimed at challenging standard clinical CT as regards to the typical diagnostic examinations; but it has already proven unique for a number of dedicated CT applications, offering distinct practical advantages, above all the availability of immediate CT imaging in the interventional suite or the operating room. (orig.)

  15. Segmentation of urinary bladder in CT urography (CTU) using CLASS with enhanced contour conjoint procedure

    Science.gov (United States)

    Cha, Kenny; Hadjiiski, Lubomir; Chan, Heang-Ping; Cohan, Richard H.; Caoili, Elaine M.; Zhou, Chuan

    2014-03-01

    We are developing a computerized method for bladder segmentation in CT urography (CTU) for computeraided diagnosis of bladder cancer. A challenge for computerized bladder segmentation in CTU is that the bladder often contains regions filled with intravenous (IV) contrast and without contrast. Previously, we proposed a Conjoint Level set Analysis and Segmentation System (CLASS) consisting of four stages: preprocessing and initial segmentation, 3D and 2D level set segmentation, and post-processing. In case the bladder is partially filled with contrast, CLASS segments the non-contrast (NC) region and the contrast (C) filled region separately and conjoins the contours with a Contour Conjoint Procedure (CCP). The CCP is not trivial. Inaccuracies in the NC and C contours may cause CCP to exclude portions of the bladder. To alleviate this problem, we implemented model-guided refinement to propagate the C contour if the level set propagation in the region stops prematurely due to substantial non-uniformity of the contrast. An enhanced CCP with regularized energies further propagates the conjoint contours to the correct bladder boundary. Segmentation performance was evaluated using 70 cases. For all cases, 3D hand segmented contours were obtained as reference standard, and computerized segmentation accuracy was evaluated in terms of average volume intersection %, average % volume error, and average minimum distance. With enhanced CCP, those values were 84.4±10.6%, 8.3±16.1%, 3.4±1.8 mm, respectively. With CLASS, those values were 74.6±13.1%, 19.6±18.6%, 4.4±2.2 mm, respectively. The enhanced CCP improved bladder segmentation significantly (p<0.001) for all three performance measures.

  16. Computed tomography (CT) and diastematomyelia's diagnosis

    International Nuclear Information System (INIS)

    Santos, M.B. dos; Luca, V. de; Ferreira, M.A.S.; Barros, A.P. de

    1982-01-01

    After a case of diastematomyelia observed at the University Hospital (Federal University of Rio de Janeiro, Brazil) a review is done of the pertaining literature, and the contribution of the computed tomography for the diagnosis of this disease is emphasized. (Author) [pt

  17. PET/CT image fusion error due to urinary bladder filling changes: consequence and correction.

    Science.gov (United States)

    Heiba, Sherif I; Raphael, Barbara; Castellon, Ivan; Altinyay, Erkan; Sandella, Nick; Rosen, Gerald; Abdel-Dayem, Hussein M

    2009-10-01

    A considerable change of urinary bladder (UB) shape in PET compared with CT in integrated PET/CT system is frequently noted. This study initially evaluated this finding with and without oral contrast (OC) use. In addition, a one bed pelvic section (PLV) repeat acquisition was investigated as a solution to this problem. (18)FDG PET/CTs of 88 patients were analyzed. OC was administered in 68 patients, of whom 31 had PLV images taken 5-10 min later. Three-dimensional mid-UB CT and PET matching measurements were compared. In addition, UB walls displacement between CT and PET were analyzed. The mean UB height was significantly increased (P errors of UB can be substantially resolved through a separate PLV acquisition presumably due to the shorter time interval of UB scan completion between CT and PET.

  18. Computed Tomography (CT) Perfusion in Abdominal Cancer

    DEFF Research Database (Denmark)

    Hansen, Martin Lundsgaard; Norling, Rikke; Lauridsen, Carsten

    2013-01-01

    for assessment of vascularity. CT perfusion has also been used for tumor characterization, staging of disease, response evaluation of newer drugs targeted towards angiogenesis and as a method for early detection of recurrence after radiation and embolization. There are several software solutions available...

  19. Cystoscopic optical coherence tomography for urinary bladder imaging in vivo

    Science.gov (United States)

    Wang, Z. G.; Adler, H.; Chan, D.; Jain, A.; Xie, H. K.; Wu, Z. L.; Pan, Y. T.

    2006-02-01

    This paper summarizes the development of new 2D MEMS mirrors and the pertinent modification to improve OCT endoscopic catheter packaging suitable for in vivo imaging diagnosis of bladder cancers. Comparative study of the newly developed endocopic OCT versus the bench-top OCT is presented. Results of in vivo OCT cystoscopy based on a porcine acute inflammation model are presented to compare time-domain OCT and spectral-domain OCT for in vivo imaging. In addition, results of spectral-domain Doppler OCT are presented to image blood flow in the lamina propria of the bladder. The results of our in vivo animal study using the presented OCT endoscope are discussed for potential problems in the future clinical applications.

  20. Individualized Nonadaptive and Online-Adaptive Intensity-Modulated Radiotherapy Treatment Strategies for Cervical Cancer Patients Based on Pretreatment Acquired Variable Bladder Filling Computed Tomography Scans

    International Nuclear Information System (INIS)

    Bondar, M.L.; Hoogeman, M.S.; Mens, J.W.; Quint, S.; Ahmad, R.; Dhawtal, G.; Heijmen, B.J.

    2012-01-01

    Purpose: To design and evaluate individualized nonadaptive and online-adaptive strategies based on a pretreatment established motion model for the highly deformable target volume in cervical cancer patients. Methods and Materials: For 14 patients, nine to ten variable bladder filling computed tomography (CT) scans were acquired at pretreatment and after 40 Gy. Individualized model-based internal target volumes (mbITVs) accounting for the cervix and uterus motion due to bladder volume changes were generated by using a motion-model constructed from two pretreatment CT scans (full and empty bladder). Two individualized strategies were designed: a nonadaptive strategy, using an mbITV accounting for the full-range of bladder volume changes throughout the treatment; and an online-adaptive strategy, using mbITVs of bladder volume subranges to construct a library of plans. The latter adapts the treatment online by selecting the plan-of-the-day from the library based on the measured bladder volume. The individualized strategies were evaluated by the seven to eight CT scans not used for mbITVs construction, and compared with a population-based approach. Geometric uniform margins around planning cervix–uterus and mbITVs were determined to ensure adequate coverage. For each strategy, the percentage of the cervix–uterus, bladder, and rectum volumes inside the planning target volume (PTV), and the clinical target volume (CTV)-to-PTV volume (volume difference between PTV and CTV) were calculated. Results: The margin for the population-based approach was 38 mm and for the individualized strategies was 7 to 10 mm. Compared with the population-based approach, the individualized nonadaptive strategy decreased the CTV-to-PTV volume by 48% ± 6% and the percentage of bladder and rectum inside the PTV by 5% to 45% and 26% to 74% (p < 0.001), respectively. Replacing the individualized nonadaptive strategy by an online-adaptive, two-plan library further decreased the percentage of

  1. Leiomyoma of Bladder

    Directory of Open Access Journals (Sweden)

    Sudhakar P

    2008-01-01

    Full Text Available A case of leiomyoma of urinary bladder, a rare benign tumor, is presented. The patient was a 45-year-old woman with long duration history of dysuria. Intravenous urography (IVU, ultrasound (US, computed tomography (CT and biopsy diagnosed this case accurately. The clinical presentation, imaging findings and management of this benign tumor are discussed.

  2. Contouring and Constraining Bowel on a Full-Bladder Computed Tomography Scan May Not Reflect Treatment Bowel Position and Dose Certainty in Gynecologic External Beam Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Yaparpalvi, Ravindra, E-mail: ryaparpa@montefiore.org; Mehta, Keyur J.; Bernstein, Michael B.; Kabarriti, Rafi; Hong, Linda X.; Garg, Madhur K.; Guha, Chandan; Kalnicki, Shalom; Tomé, Wolfgang A.

    2014-11-15

    Purpose: To evaluate, in a gynecologic cancer setting, changes in bowel position, dose-volume parameters, and biological indices that arise between full-bladder (FB) and empty-bladder (EB) treatment situations; and to evaluate, using cone beam computed tomography (CT), the validity of FB treatment presumption. Methods and Materials: Seventeen gynecologic cancer patients were retrospectively analyzed. Empty-bladder and FB CTs were obtained. Full-bladder CTs were used for planning and dose optimization. Patients were given FB instructions for treatment. For the study purpose, bowel was contoured on the EB CTs for all patients. Bowel position and volume changes between FB and EB states were determined. Full-bladder plans were applied on EB CTs for determining bowel dose-volume changes in EB state. Biological indices (generalized equivalent uniform dose and normal tissue complication probability) were calculated and compared between FB and EB. Weekly cone beam CT data were available in 6 patients to assess bladder volume at treatment. Results: Average (±SD) planned bladder volume was 299.7 ± 68.5 cm{sup 3}. Median bowel shift in the craniocaudal direction between FB and EB was 12.5 mm (range, 3-30 mm), and corresponding increase in exposed bowel volume was 151.3 cm{sup 3} (range, 74.3-251.4 cm{sup 3}). Absolute bowel volumes receiving 45 Gy were higher for EB compared with FB (mean 328.0 ± 174.8 vs 176.0 ± 87.5 cm{sup 3}; P=.0038). Bowel normal tissue complication probability increased 1.5× to 23.5× when FB planned treatments were applied in the EB state. For the study, the mean percentage value of relative bladder volume at treatment was 32%. Conclusions: Full-bladder planning does not necessarily translate into FB treatments, with a patient tendency toward EB. Given the uncertainty in daily control over bladder volume for treatment, we strongly recommend a “planning-at-risk volume bowel” (PRV{sub B}owel) concept to account for bowel motion

  3. Reducing image noise in computed tomography (CT) colonography: effect of an integrated circuit CT detector.

    Science.gov (United States)

    Liu, Yu; Leng, Shuai; Michalak, Gregory J; Vrieze, Thomas J; Duan, Xinhui; Qu, Mingliang; Shiung, Maria M; McCollough, Cynthia H; Fletcher, Joel G

    2014-01-01

    To investigate whether the integrated circuit (IC) detector results in reduced noise in computed tomography (CT) colonography (CTC). Three hundred sixty-six consecutive patients underwent clinically indicated CTC using the same CT scanner system, except for a difference in CT detectors (IC or conventional). Image noise, patient size, and scanner radiation output (volume CT dose index) were quantitatively compared between patient cohorts using each detector system, with separate comparisons for the abdomen and pelvis. For the abdomen and pelvis, despite significantly larger patient sizes in the IC detector cohort (both P noise was significantly lower (both P 0.18). Based on the observed image noise reduction, radiation dose could alternatively be reduced by approximately 20% to result in similar levels of image noise. Computed tomography colonography images acquired using the IC detector had significantly lower noise than images acquired using the conventional detector. This noise reduction can permit further radiation dose reduction in CTC.

  4. Enhancing early bladder cancer detection with fluorescence-guided endoscopic optical coherence tomography

    Science.gov (United States)

    Pan, Y. T.; Xie, T. Q.; Du, C. W.; Bastacky, S.; Meyers, S.; Zeidel, M. L.

    2003-12-01

    We report an experimental study of the possibility of enhancing early bladder cancer diagnosis with fluorescence-image-guided endoscopic optical coherence tomography (OCT). After the intravesical instillation of a 10% solution of 5-aminolevulinic acid, simultaneous fluorescence imaging (excitation of 380-420 nm, emission of 620-700 nm) and OCT are performed on rat bladders to identify the photochemical and morphological changes associated with uroepithelial tumorigenesis. The preliminary results of our ex vivo study reveal that both fluorescence and OCT can identify early uroepithelial cancers, and OCT can detect precancerous lesions (e.g., hyperplasia) that fluorescence may miss. This suggests that a cystoscope combining 5-aminolevulinic acid fluorescence and OCT imaging has the potential to enhance the efficiency and sensitivity of early bladder cancer diagnosis.

  5. Preliminary assessment of fluorine-18 fluorodeoxyglucose positron emission tomography in patients with bladder cancer

    International Nuclear Information System (INIS)

    Kosuda, S.; Kison, P.V.; Greenough, R.; Grossman, H.B.; Wahl, R.L.

    1997-01-01

    The purpose of this study was to assess the feasibility of imaging of bladder cancer with fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) scanning. We studied 12 patients with histologically proven bladder cancer who had undergone surgical procedures and/or radiotherapy. Retrograde irrigation of the urinary bladder with 1000-3710 ml saline was performed during nine of the studies. Dynamic and static PET images were obtained, and standardized uptake value images were reconstructed. FDG-PET scanning was true-positive in eight patients (66.7%), but false-negative in four (33.3%). Of 20 organs with tumor mass lesions confirmed pathologically or clinically, 16 (80%) were detected by FDG-PET scanning. FDG-PET scanning detected all of 17 distant metastatic lesions and two of three proven regional lymph node metastases. FDG-PET was also capable of differentiating viable recurrent bladder cancer from radiation-induced alterations in two patients. In conclusion, these preliminary data indicate the feasibility of FDG-PET imaging in patients with bladder cancer, although a major remaining pitfall is intense FDG accumulation in the urine. (orig.). With 3 figs., 1 tab

  6. Multilayered disease-mimicking bladder phantom with realistic surface topology for optical coherence tomography

    Science.gov (United States)

    Smith, Gennifer T.; Lurie, Kristen L.; Khan, Saara A.; Liao, Joseph C.; Ellerbee, Audrey K.

    2014-03-01

    Optical coherence tomography (OCT) has shown potential as a complementary modality to white light cystoscopy (WLC), the gold standard for imaging bladder cancer. OCT can visualize sub-surface details of the bladder wall, which enables it to stage cancers and detect tumors that are otherwise invisible to WLC. Currently, OCT systems have too slow a speed and too small a field of view for comprehensive bladder imaging, which limits its clinical utility. Validation and feasibility testing of technological refinements aimed to provide faster imaging and wider fields of view necessitates a realistic bladder phantom. We present a novel process to fabricate the first such phantom that mimics both the optical and morphological properties of layers of the healthy and pathologic bladder wall as they characteristically appear with OCT. The healthy regions of the silicone-based phantom comprises three layers: the urothelium, lamina propria and muscularis propria, each containing an appropriate concentration of titanium dioxide to mimic its distinct scattering properties. As well, the layers each possess a unique surface appearance imposed by a textured mold. Within this phantom, pathologic tissue-mimicking regions are created by thickening specific layers or creating inclusions that disrupt the layered appearance of the bladder wall, as is characteristic of bladder carcinomas. This phantom can help to evaluate the efficacy of new OCT systems and software for tumor localization. Moreover, the procedure we have developed is highly generalizable for the creation of OCT-relevant, multi-layer phantoms for tissues that incorporate diseased states characterized by the loss of layered structures.

  7. Dog Ear-Like Bladder Herniation

    Directory of Open Access Journals (Sweden)

    Ferhat Cuce

    2014-06-01

    Full Text Available The hernia content involving a bladder segment occurs in 1-4 % of cases of the inguinal hernias. Inguinoscrotal bladder hernias are usually found incidentally on radiological examinations or at the time of herniorrhaphy. We present an adult case that has a left inguinal bladder hernia detected and evaluated by sonography, intravenous pyelography (IVP, and computerized tomography (CT. [Arch Clin Exp Surg 2014; 3(3.000: 187-189

  8. 18 F-fluorodeoxyglucose positron emission tomography-computed tomography for preoperative lymph node staging in patients undergoing radical cystectomy for bladder cancer: a prospective study.

    Science.gov (United States)

    Hitier-Berthault, Maryam; Ansquer, Catherine; Branchereau, Julien; Renaudin, Karine; Bodere, Françoise; Bouchot, Olivier; Rigaud, Jérôme

    2013-08-01

    The objective of our study was to analyze the diagnostic performance of (18) F-fluorodeoxyglucose positron emission tomography-computed tomography for lymph node staging in patients with bladder cancer before radical cystectomy and to compare it with that of computed tomography. A total of 52 patients operated on between 2005 and 2010 were prospectively included in this prospective, mono-institutional, open, non-randomized pilot study. Patients who had received neoadjuvant chemotherapy or radiotherapy were excluded. (18) F-fluorodeoxyglucose positron emission tomography-computed tomography in addition to computed tomography was carried out for lymph node staging of bladder cancer before radical cystectomy. Lymph node dissection during radical cystectomy was carried out. Findings from (18) F-fluorodeoxyglucose positron emission tomography-computed tomography and computed tomography were compared with the results of definitive histological examination of the lymph node dissection. The diagnostic performance of the two imaging modalities was assessed and compared. The mean number of lymph nodes removed during lymph node dissection was 16.5 ± 10.9. Lymph node metastasis was confirmed on histological examination in 22 cases (42.3%). This had been suspected in five cases (9.6%) on computed tomography and in 12 cases (23.1%) on (18) F-fluorodeoxyglucose positron emission tomography-computed tomography. Sensitivity, specificity, positive predictive value, negative predictive value, relative risk and accuracy were 9.1%, 90%, 40%, 57.4%, 0.91 and 55.7%, respectively, for computed tomography, and 36.4%, 86.7%, 66.7%, 65%, 2.72, 65.4%, respectively, for (18) F-fluorodeoxyglucose positron emission tomography-computed tomography. (18) F-fluorodeoxyglucose positron emission tomography-computed tomography is more reliable than computed tomography for preoperative lymph node staging in patients with invasive bladder carcinoma undergoing radical cystectomy. © 2012 The Japanese

  9. [Basic principles of flat detector computed tomography (FD-CT)].

    Science.gov (United States)

    Kyriakou, Y; Struffert, T; Dörfler, A; Kalender, W A

    2009-09-01

    Flat detectors (FDs) have been developed for use in radiography and fluoroscopy to replace standard X-ray film, film-screen combinations and image intensifiers (II). In comparison to X-ray film and II, FD technology offers higher dynamic range, dose reduction, fast digital readout and the possibility for dynamic acquisitions of image series, yet keeping to a compact design. It appeared logical to employ FD designs also for computed tomography (CT) imaging. FDCT has meanwhile become widely accepted for interventional and intra-operative imaging using C-arm systems. Additionally, the introduction of FD technology was a milestone for soft-tissue CT imaging in the interventional suite which was not possible with II systems in the past. This review focuses on technical and performance issues of FD technology and its wide range of applications for CT imaging. FDCT is not aimed at challenging standard clinical CT as regards to the typical diagnostic examinations, but it has already proven unique for a number of dedicated CT applications offering distinct practical advantages, above all the availability of immediate CT imaging during an intervention.

  10. Basics principles of flat detector computed tomography (FD-CT)

    International Nuclear Information System (INIS)

    Kyriakou, Y.; Struffert, T.; Doerfler, A.; Kalender, W.A.

    2009-01-01

    Flat detectors (FDs) have been developed for use in radiography and fluoroscopy to replace standard X-ray film, film-screen combinations and image intensifiers (II). In comparison to X-ray film and II, FD technology offers higher dynamic range, dose reduction, fast digital readout and the possibility for dynamic acquisitions of image series, yet keeping to a compact design. It appeared logical to employ FD designs also for computed tomography (CT) imaging. FDCT has meanwhile become widely accepted for interventional and intra-operative imaging using C-arm systems. Additionally, the introduction of FD technology was a milestone for soft-tissue CT imaging in the interventional suite which was not possible with II systems in the past. This review focuses on technical and performance issues of FD technology and its wide range of applications for CT imaging. FDCT is not aimed at challenging standard clinical CT as regards to the typical diagnostic examinations, but it has already proven unique for a number of dedicated CT applications offering distinct practical advantages, above all the availability of immediate CT imaging during an intervention. (orig.) [de

  11. Correction of an image size difference between positron emission tomography (PET) and computed tomography (CT) improves image fusion of dedicated PET and CT.

    NARCIS (Netherlands)

    Vogel, W.V.; Dalen, J.A. van; Schinagl, D.A.X.; Kaanders, J.H.A.M.; Huisman, H.J.; Corstens, F.H.M.; Oyen, W.J.G.

    2006-01-01

    AIM: Clinical work in software positron emission tomography/computed tomography (PET/CT) image fusion has raised suspicion that the image sizes of PET and CT differ slightly from each other, thus rendering the images suboptimal for image fusion. The aim of this study was to evaluate the extent of

  12. Predictive value of excretory urography, ultrasonography, computerized tomography, and liver and bone scan in the staging of bilharzial bladder cancer in Saudi Arabia

    International Nuclear Information System (INIS)

    Hanash, K.A.; Bissada, N.K.; Abla, A.; Esmail, D.; Dowling, A.

    1984-01-01

    The role of ultrasonography, computed tomography (CT), and radioisotopic scanning in the staging of bilharzial bladder cancer has not been reported previously. Forty patients with invasive bladder cancer seen at the King Faisal Specialist Hospital and Research Centre between January 1978 and June 1981 underwent complete preoperative workup for staging of their tumors prior to radical cystectomy. The preoperative radiologic investigations included excretory urography (IVP), ultrasonography (US), CT of the pelvis, and liver and bone scans. The results of these investigations were compared with the operative and pathologic staging. Ninety-three percent of the patients with bilharzial cancer had evidence of ureteric obstruction on IVP compared with 22% of the nonbilharzial cancer patients. The presence of ureteric obstruction in these patients did not correlate with the stage of the disease with 83% of the patients with superficial tumors (T1 and T2) having hydroureteronephrosis. Ultrasonography and CT had an 83% accuracy in the staging of superficial tumors. Stage T3 tumors were understaged in 14% of the cases. Ultrasonography did not differentiate Stages T3 and T4 tumors while CT scan differentiated these two stages in 57% of the cases. Bone scan failed to reveal evidence of metastatic disease in any of the bilharzial cancer patients. Liver scan was suspicious for liver metastases in two patients with bilharzial cancers in whom open liver biopsy revealed only hepatic bilharziasis. Of all the radiographic studies, US or preferably CT scan seem to be of some value in the staging of bilharzial tumors localized to the bladder. Bone and liver scans are probably of no cost effective benefit

  13. Comparison of CLASS and ITK-SNAP in segmentation of urinary bladder in CT urography

    Science.gov (United States)

    Cha, Kenny; Hadjiiski, Lubomir; Chan, Heang-Ping; Caoili, Elaine M.; Cohan, Richard H.; Zhou, Chuan

    2014-03-01

    We are developing a computerized method for bladder segmentation in CT urography (CTU) for computeraided diagnosis of bladder cancer. We have developed a Conjoint Level set Analysis and Segmentation System (CLASS) consisting of four stages: preprocessing and initial segmentation, 3D and 2D level set segmentation, and post-processing. In case the bladder contains regions filled with intravenous (IV) contrast and without contrast, CLASS segments the noncontrast (NC) region and the contrast (C) filled region separately and conjoins the contours. In this study, we compared the performance of CLASS to ITK-SNAP 2.4, which is a publicly available software application for segmentation of structures in 3D medical images. ITK-SNAP performs segmentation by using the edge-based level set on preprocessed images. The level set were initialized by manually placing a sphere at the boundary between the C and NC parts of the bladders with C and NC regions, and in the middle of the bladders that had only C or NC region. Level set parameters and the number of iterations were chosen after experimentation with bladder cases. Segmentation performances were compared using 30 randomly selected bladders. 3D hand-segmented contours were obtained as reference standard, and computerized segmentation accuracy was evaluated in terms of the average volume intersection %, average % volume error, average absolute % volume error, average minimum distance, and average Jaccard index. For CLASS, the values for these performance metrics were 79.0±8.2%, 16.1±16.3%, 19.9±11.1%, 3.5±1.3 mm, 75.7±8.4%, respectively. For ITK-SNAP, the corresponding values were 78.8±8.2%, 8.3±33.1%, 24.2±23.7%, 5.2±2.6 mm, 71.0±15.4%, respectively. CLASS on average performed better and exhibited less variations than ITK-SNAP for bladder segmentation.

  14. Forced diuresis and dual-phase 18F-fluorodeoxyglucose-PET/CT scan for restaging of urinary bladder cancers

    International Nuclear Information System (INIS)

    Harkirat, S; Anand, SS; Jacob, MJ

    2010-01-01

    The results of 18 F-fluorodeoxyglucose (FDG)-PET imaging carried out with the current standard techniques for assessment of urinary tract cancers have been reported to be less than satisfactory because of the urinary excretion of the tracer. To investigate the role of dual-phase FDG-PET/CT in the restaging of invasive cancers of the urinary bladder, with delayed imaging after forced diuresis and oral hydration as the scanning protocol. FDG-PET has been considered to be of limited value for the detection of urinary tract cancers because of interference by the FDG excreted in urine. We investigated the efficacy of delayed FDG-PET/CT in the restaging of invasive bladder cancer, with imaging performed after intravenous (IV) administration of a potent diuretic and oral hydration. Twenty-nine patients with invasive cancer of the urinary bladder were included in this study. Patients were divided into two groups: Group I (22 patients) included cases with invasive bladder cancer who had not undergone cystectomy and group II (seven patients) included cases with invasive bladder cancer who had undergone cystectomy and urinary diversion procedure. All patients underwent FDG-PET/CT scan from the skull base to the mid-thighs 60 min after IV injection of 370 mega-Becquerel (MBq) of FDG. Additional delayed images were acquired 60-90 min after IV furosemide and oral hydration. PET/CT data were analyzed as PET and CT images studied separately as well as fused PET/CT images and the findings were recorded. The imaging findings were confirmed by cystoscopy, biopsy or follow-up PET/CT. The technique was successful in achieving adequate washout of urinary FDG and overcame the problems posed by the excess FDG in the urinary tract. Hypermetabolic lesions could be easily detected by PET and precisely localized to the bladder wall, perivesical region and pelvic lymph nodes. PET/CT delayed images were able to demonstrate 16 intravesical lesions (in 13 patients), with excellent clarity. Lymph

  15. Endoscopic optical coherence tomography with a modified microelectromechanical systems mirror for detection of bladder cancers

    Science.gov (United States)

    Xie, Tuqiang; Xie, Huikai; Fedder, Gary K.; Pan, Yingtian

    2003-11-01

    Experimental results of a modified micromachined microelectromechanical systems (MEMS) mirror for substantial enhancement of the transverse laser scanning performance of endoscopic optical coherence tomography (EOCT) are presented. Image distortion due to buckling of MEMS mirror in our previous designs was analyzed and found to be attributed to excessive internal stress of the transverse bimorph meshes. The modified MEMS mirror completely eliminates bimorph stress and the resultant buckling effect, which increases the wobbling-free angular optical actuation to greater than 37°, exceeding the transverse laser scanning requirements for EOCT and confocal endoscopy. The new optical coherence tomography (OCT) endoscope allows for two-dimensional cross-sectional imaging that covers an area of 4.2 mm × 2.8 mm (limited by scope size) and at roughly 5 frames/s instead of the previous area size of 2.9 mm × 2.8 mm and is highly suitable for noninvasive and high-resolution imaging diagnosis of epithelial lesions in vivo. EOCT images of normal rat bladders and rat bladder cancers are compared with the same cross sections acquired with conventional bench-top OCT. The results clearly demonstrate the potential of EOCT for in vivo imaging diagnosis and precise guidance for excisional biopsy of early bladder cancers.

  16. Detection of Lymph Node Metastasis in Patients with Bladder Cancer using Maximum Standardised Uptake Value and 18F-fluorodeoxyglucose Positron Emission Tomography/Computed Tomography: Results from a High-volume Centre Including Long-term Follow-up.

    Science.gov (United States)

    Vind-Kezunovic, Stefan; Bouchelouche, Kirsten; Ipsen, Pia; Høyer, Søren; Bell, Cathrine; Bjerggaard Jensen, Jørgen

    2017-06-23

    Preoperative staging with 18 F-fluorodeoxyglucose ( 18 F-FDG) positron emission tomography (PET) combined with computed tomography (CT) is used for the evaluation of metastatic disease in patients with invasive bladder cancer. The use of quantification with maximum standardized uptake value (SUVmax) of regional lymph nodes (LNs) has been suggested to increase the diagnostic ability for detection of malignancy. Assessment of the utility and clinical relevance of SUVmax in 18 F-FDG PET in detecting regional nodal metastases in patients considered for radical cystectomy. From 2011 to 2014, we identified a total of 119 patients with urothelial carcinoma who underwent radical cystectomy with extended LN dissection; additionally, 12 patients were identified by preoperative biopsy. All patients underwent 18 F-FDG PET/CT before treatment recommendation. Pathological findings were compared with preoperative PET/CT staging and analysed in a regional- or patient-based model according to SUVmax values. In total, 2291 LNs were identified in 131 patients; locoregional involvement of 85 LNs were confirmed in 34 patients. SUVmax >2 analysis: sensitivity±95% confidence interval of 79.4% (62.1-91.3) and specificity 66.5% (55.7-75.3). SUVmax >4 based analysis: sensitivity was 61.8% (43.6-77.8) and specificity was 84.5% (75.8-91.1). Two years of follow-up implied that higher SUVmax is correlated with higher recurrence risk, independent of conventional pathological findings. 18 F-FDG PET/CT using SUVmax of LNs is a useful tool for preoperative evaluation of pelvic LN metastases from invasive bladder cancer and contributes to the selection of patients for personalized treatment. In this report, we establish that it is possible to identify disease from bladder cancer in the lymphatic tissue surrounding the bladder using a scan analysis. This assists in the selection of treatment for patients with bladder cancer and may spare patients from unnecessary procedures. Copyright © 2017

  17. Clinical value of whole body fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography in the detection of metastatic bladder cancer.

    Science.gov (United States)

    Yang, Zhongyi; Pan, Lingling; Cheng, Jingyi; Hu, Silong; Xu, Junyan; Ye, Dingwei; Zhang, Yingjian

    2012-07-01

    To investigate the value of whole-body fluorine-18 2-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography for the detection of metastatic bladder cancer. From December 2006 to August 2010, 60 bladder cancer patients (median age 60.5 years old, range 32-96) underwent whole body positron emission tomography/computed tomography positron emission tomography/computed tomography. The diagnostic accuracy was assessed by performing both organ-based and patient-based analyses. Identified lesions were further studied by biopsy or clinically followed for at least 6 months. One hundred and thirty-four suspicious lesions were identified. Among them, 4 primary cancers (2 pancreatic cancers, 1 colonic and 1 nasopharyngeal cancer) were incidentally detected, and the patients could be treated on time. For the remaining 130 lesions, positron emission tomography/computed tomography detected 118 true positive lesions (sensitivity = 95.9%). On the patient-based analysis, the overall sensitivity and specificity resulted to be 87.1% and 89.7%, respectively. There was no difference of sensitivity and specificity in patients with or without adjuvant treatment in terms of detection of metastatic sites by positron emission tomography/computed tomography. Compared with conventional imaging modality, positron emission tomography/computed tomography correctly changed the management in 15 patients (25.0%). Positron emission tomography/computed tomography has excellent sensitivity and specificity in the detection of metastatic bladder cancer and it provides additional diagnostic information compared to standard imaging techniques. © 2012 The Japanese Urological Association.

  18. Clinical value of whole body fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography in the detection of metastatic bladder cancer

    International Nuclear Information System (INIS)

    Yang Zhongyi; Pan Lingling; Cheng Jingyi; Hu Silong; Xu Junyan; Zhang Yingjian; Ye Dingwei

    2012-01-01

    The objective of this study was to investigate the value of whole-body fluorine-18 2-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography for the detection of metastatic bladder cancer. From December 2006 to August 2010, 60 bladder cancer patients (median age 60.5 years old, range 32-96) underwent whole body positron emission tomography/computed tomography positron emission tomography/computed tomography. The diagnostic accuracy was assessed by performing both organ-based and patient-based analyses. Identified lesions were further studied by biopsy or clinically followed for at least 6 months. One hundred and thirty-four suspicious lesions were identified. Among them, 4 primary cancers (2 pancreatic cancers, 1 colonic and 1 nasopharyngeal cancer) were incidentally detected, and the patients could be treated on time. For the remaining 130 lesions, positron emission tomography/computed tomography detected 118 true positive lesions (sensitivity=95.9%). On the patient-based analysis, the overall sensitivity and specificity resulted to be 87.1% and 89.7%, respectively. There was no difference of sensitivity and specificity in patients with or without adjuvant treatment in terms of detection of metastatic sites by positron emission tomography/computed tomography. Compared with conventional imaging modality, positron emission tomography/computed tomography correctly changed the management in 15 patients (25.0%). Positron emission tomography/computed tomography has excellent sensitivity and specificity in the detection of metastatic bladder cancer and it provides additional diagnostic information compared to standard imaging techniques. (author)

  19. SU-F-J-81: Evaluation of Automated Deformable Registration Between Planning Computed Tomography (CT) and Daily Cone Beam CT Images Over the Course of Prostate Cancer Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Matney, J; Hammers, J; Kaidar-Person, O; Wang, A; Chen, R; Das, S; Marks, L; Mavroidis, P [University North Carolina, Chapel Hill, NC (United States)

    2016-06-15

    Purpose: To compute daily dose delivered during radiotherapy, deformable registration needs to be relatively fast, automated, and accurate. The aim of this study was to evaluate the performance of commercial deformable registration software for deforming between two modalities: planning computed tomography (pCT) images acquired for treatment planning and cone beam (CB) CT images acquired prior to each fraction of prostate cancer radiotherapy. Methods: A workflow was designed using MIM Software™ that aligned and deformed pCT into daily CBCT images in two steps: (1) rigid shifts applied after daily CBCT imaging to align patient anatomy to the pCT and (2) normalized intensity-based deformable registration to account for interfractional anatomical variations. The physician-approved CTV and organ and risk (OAR) contours were deformed from the pCT to daily CBCT over the course of treatment. The same structures were delineated on each daily CBCT by a radiation oncologist. Dice similarity coefficient (DSC) mean and standard deviations were calculated to quantify the deformable registration quality for prostate, bladder, rectum and femoral heads. Results: To date, contour comparisons have been analyzed for 31 daily fractions of 2 of 10 of the cohort. Interim analysis shows that right and left femoral head contours demonstrate the highest agreement (DSC: 0.96±0.02) with physician contours. Additionally, deformed bladder (DSC: 0.81±0.09) and prostate (DSC: 0.80±0.07) have good agreement with physician-defined daily contours. Rectum contours have the highest variations (DSC: 0.66±0.10) between the deformed and physician-defined contours on daily CBCT imaging. Conclusion: For structures with relatively high contrast boundaries on CBCT, the MIM automated deformable registration provided accurate representations of the daily contours during treatment delivery. These findings will permit subsequent investigations to automate daily dose computation from CBCT. However

  20. Contrast-enhanced computed tomography of the primary tumor in muscle invasive carcinoma of the urinary bladder

    International Nuclear Information System (INIS)

    Sager, E.M.

    1991-01-01

    Patients with muscle invasive carcinoma of the urinary bladder were examined with contrast-enhanced CT of the primary tumor. A specially designed technique was developed to increase the diagnostic potential of CT. The most important points about the technique were controlled filling of the bladder, the use of thin slices, series of scans before and after intravenous injection of contrast medium, and long scanning times in the precontrast series. The absorbed dose to the patient resulting from the new technique was found to be within the range of the dose from urography or barium enema. This dose was considered to be acceptable given the diagnostic gain of the procedure. Features of irradiated bladder tumors were analysed to find which parameter correlated with persistent malignancy. High contrast enhancement of a tumor relative to the bladder wall was found to be the best indicator of a malignant tumour after irradiation. 127 refs

  1. Is [F-18]-fluorodeoxyglucose FDG-PET/CT better than CT alone for the preoperative lymph node staging of muscle invasive bladder cancer?

    Energy Technology Data Exchange (ETDEWEB)

    Uttam, Mete; Pravin, Nayak; Anish, Bhattacharya; Nandita, Kakkar; Arup, Mandal, E-mail: uttam_mete@yahoo.com [PGIMER, Chandigarh, (India)

    2016-03-15

    Objective: To evaluate whether the use of [F-18]-FDG-PET/CT can accurately predict pelvic lymph node metastasis in patients with muscle invasive TCC of the bladder undergoing radical cystectomy. Materials and methods: Fifteen patients with muscle invasive bladder cancer had undergone FDG-PET/CT scan from the skull base to the mid-thighs after IV injection of 6.5MBq (Mega-Becquerel)/Kg of FDG. After intravenous hydration IV furosemide was given to overcome the difficulties posed by urinary excretion of {sup 18}F-FDG. PET/ CT data were analyzed as PET and CT images studied separately as well as fused PET/ CT images. The imaging findings were correlated with the histopathology of the nodes (gold standard). Results: CT and FDG-PET had demonstrated positive lymph nodes in 9 & 8 patients respectively. Among the 15 patients 3 had documented metastasis on histopathology. Both CT and PET could detect the nodes in all these 3 patients (100% sensitivity). Nodes were histologically negative amongst 6&5 patients who had node involvement by CT and PET respectively. Therefore, specificity, positive predictive value (PPV) & negative predictive value (NPV) for CT and PET/CT were 50%, 33.3%, 100% and 58.3%, 37.5%, 100% respectively. Conclusion: The theoretical advantage of this cutting edge technology for whole body imaging has not been translated into clinical practice as we found minimal advantage of combined FDG-PET/CT over CT alone for nodal staging of muscle invasive bladder cancer. This may be due to substantial overlap between standardized uptake values (SUVs) from active inflammatory processes with those of malignant lesion. (author)

  2. Diagnostic value of [18F] FDG-PET and PET/CT in urinary bladder cancer: a meta-analysis.

    Science.gov (United States)

    Zhang, Huojun; Xing, Wei; Kang, Qinqin; Chen, Chao; Wang, Linhui; Lu, Jianping

    2015-05-01

    An early diagnosis of urinary bladder cancer is crucial for early treatment and management. The objective of this systematic review was to assess the overall diagnostic accuracy of 18 F FDG-PET and PET/CT in urinary bladder cancer with meta-analysis. The PubMed and CNKI databases were searched for the eligible studies published up to June 01, 2014. The sensitivity, specificity, and other measures of accuracy of 18 F FDG-PET and PET/CT in the diagnosis of urinary bladder cancer were pooled along with 95 % confidence intervals (CI). Summary receiver operating characteristic (ROC) curves were used to summarize overall test performance. Ten studies met our inclusion criteria. The summary estimates for 18 F FDG-PET and PET/CT in the diagnosis of urinary bladder cancer in meta-analysis were as follows: a pooled sensitivity, 0.82 (95 % confidence interval [CI], 0.75 to 0.88); a pooled specificity, 0.92 (95 % CI, 0.87 to 0.95); positive likelihood ratio, 6.80 (95 % CI, 4.31 to 10.74); negative likelihood ratio, 0.27 (95 % CI, 0.19 to 0.36); and diagnostic odds ratio, 25.18 (95 % CI, 17.58 to 70.4). The results indicate that 18 F FDG-PET and PET/CT are relatively high sensitive and specific for the diagnosis of urinary bladder cancer.

  3. Bladder cancer treatment response assessment using deep learning in CT with transfer learning

    Science.gov (United States)

    Cha, Kenny H.; Hadjiiski, Lubomir M.; Chan, Heang-Ping; Samala, Ravi K.; Cohan, Richard H.; Caoili, Elaine M.; Paramagul, Chintana; Alva, Ajjai; Weizer, Alon Z.

    2017-03-01

    We are developing a CAD system for bladder cancer treatment response assessment in CT. We compared the performance of the deep-learning convolution neural network (DL-CNN) using different network sizes, and with and without transfer learning using natural scene images or regions of interest (ROIs) inside and outside the bladder. The DL-CNN was trained to identify responders (T0 disease) and non-responders to chemotherapy. ROIs were extracted from segmented lesions in pre- and post-treatment scans of a patient and paired to generate hybrid pre-post-treatment paired ROIs. The 87 lesions from 82 patients generated 104 temporal lesion pairs and 6,700 pre-post-treatment paired ROIs. Two-fold cross-validation and receiver operating characteristic analysis were performed and the area under the curve (AUC) was calculated for the DL-CNN estimates. The AUCs for prediction of T0 disease after treatment were 0.77+/-0.08 and 0.75+/-0.08, respectively, for the two partitions using DL-CNN without transfer learning and a small network, and were 0.74+/-0.07 and 0.74+/-0.08 with a large network. The AUCs were 0.73+/-0.08 and 0.62+/-0.08 with transfer learning using a small network pre-trained with bladder ROIs. The AUC values were 0.77+/-0.08 and 0.73+/-0.07 using the large network pre-trained with the same bladder ROIs. With transfer learning using the large network pretrained with the Canadian Institute for Advanced Research (CIFAR-10) data set, the AUCs were 0.72+/-0.06 and 0.64+/-0.09, respectively, for the two partitions. None of the differences in the methods reached statistical significance. Our study demonstrated the feasibility of using DL-CNN for the estimation of treatment response in CT. Transfer learning did not improve the treatment response estimation. The DL-CNN performed better when transfer learning with bladder images was used instead of natural scene images.

  4. CT and Positron Emission Tomography/CT Findings of Mediastinal Extraskeletal Ewing's Sarcoma with Extensive Distant Metastasis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bom Yi; Ko, Jeong Min; Park, Hyun Jin [Dept. of Radiology, St. Vincent' s Hospital, The Catholic University of Korea College of Medicine, Suwon, (Korea, Republic of)

    2012-11-15

    Extraskeletal Ewing's sarcoma (EES) is a rare aggressive malignant tumor, usually occurring in the chest wall of children and young adults. Although EES shows aggressive growth pattern, it seldom demonstrates distant metastasis at diagnosis. Herein, we present computed tomography (CT) and positron emission tomography computed tomography (PET/CT) findings of EES in anterior mediastinum in a 68-year-old man, showing multi-organ distant metastasis at diagnosis. It is another atypical case with unusual presentation in point of old age, mediastinal location and distant metastasis at diagnosis, showing PET/CT findings.

  5. CT and Positron Emission Tomography/CT Findings of Mediastinal Extraskeletal Ewing's Sarcoma with Extensive Distant Metastasis

    International Nuclear Information System (INIS)

    Kim, Bom Yi; Ko, Jeong Min; Park, Hyun Jin

    2012-01-01

    Extraskeletal Ewing's sarcoma (EES) is a rare aggressive malignant tumor, usually occurring in the chest wall of children and young adults. Although EES shows aggressive growth pattern, it seldom demonstrates distant metastasis at diagnosis. Herein, we present computed tomography (CT) and positron emission tomography computed tomography (PET/CT) findings of EES in anterior mediastinum in a 68-year-old man, showing multi-organ distant metastasis at diagnosis. It is another atypical case with unusual presentation in point of old age, mediastinal location and distant metastasis at diagnosis, showing PET/CT findings.

  6. Bladder filling variation during conformal radiotherapy for rectal cancer

    International Nuclear Information System (INIS)

    Sithamparam, S; Ahmad, R; Sabarudin, A; Othman, Z; Ismail, M

    2017-01-01

    Conformal radiotherapy for rectal cancer is associated with small bowel toxicity mainly diarrhea. Treating patients with a full bladder is one of the practical solutions to reduce small bowel toxicity. Previous studies on prostate and cervix cancer patients revealed that maintaining consistent bladder volume throughout radiotherapy treatment is challenging. The aim of this study was to measure bladder volume variation throughout radiotherapy treatment. This study also measured the association between bladder volume changes and diarrhea. Twenty two rectal cancer patients were recruited prospectively. Patients were planned for treatment with full bladder following departmental bladder filling protocol and the planning bladder volume was measured during CT-simulation. During radiotherapy, the bladder volume was measured weekly using cone-beam computed tomography (CBCT) and compared to planning bladder volume. Incidence and severity of diarrhea were recorded during the weekly patient review. There was a negative time trend for bladder volume throughout five weeks treatment. The mean bladder volume decreased 18 % from 123 mL (SD 54 mL) during CT-simulation to 101 mL (SD 71 mL) on the 5th week of radiotherapy, but the decrease is not statistically significant. However, there was a large variation of bladder volume within each patient during treatment. This study showed an association between changes of bladder volume and diarrhea (P = 0.045). In conclusion bladder volume reduced throughout radiotherapy treatment for conformal radiotherapy for rectal cancer and there was a large variation of bladder volume within patients. (paper)

  7. Bladder filling variation during conformal radiotherapy for rectal cancer

    Science.gov (United States)

    Sithamparam, S.; Ahmad, R.; Sabarudin, A.; Othman, Z.; Ismail, M.

    2017-05-01

    Conformal radiotherapy for rectal cancer is associated with small bowel toxicity mainly diarrhea. Treating patients with a full bladder is one of the practical solutions to reduce small bowel toxicity. Previous studies on prostate and cervix cancer patients revealed that maintaining consistent bladder volume throughout radiotherapy treatment is challenging. The aim of this study was to measure bladder volume variation throughout radiotherapy treatment. This study also measured the association between bladder volume changes and diarrhea. Twenty two rectal cancer patients were recruited prospectively. Patients were planned for treatment with full bladder following departmental bladder filling protocol and the planning bladder volume was measured during CT-simulation. During radiotherapy, the bladder volume was measured weekly using cone-beam computed tomography (CBCT) and compared to planning bladder volume. Incidence and severity of diarrhea were recorded during the weekly patient review. There was a negative time trend for bladder volume throughout five weeks treatment. The mean bladder volume decreased 18 % from 123 mL (SD 54 mL) during CT-simulation to 101 mL (SD 71 mL) on the 5th week of radiotherapy, but the decrease is not statistically significant. However, there was a large variation of bladder volume within each patient during treatment. This study showed an association between changes of bladder volume and diarrhea (P = 0.045). In conclusion bladder volume reduced throughout radiotherapy treatment for conformal radiotherapy for rectal cancer and there was a large variation of bladder volume within patients.

  8. CT urography: segmentation of urinary bladder using CLASS with local contour refinement

    International Nuclear Information System (INIS)

    Cha, Kenny; Hadjiiski, Lubomir; Chan, Heang-Ping; Caoili, Elaine M; Cohan, Richard H; Zhou, Chuan

    2014-01-01

    We are developing a computerized system for bladder segmentation on CT urography (CTU), as a critical component for computer-aided detection of bladder cancer. The presence of regions filled with intravenous contrast and without contrast presents a challenge for bladder segmentation. Previously, we proposed a conjoint level set analysis and segmentation system (CLASS). In case the bladder is partially filled with contrast, CLASS segments the non-contrast (NC) region and the contrast-filled (C) region separately and automatically conjoins the NC and C region contours; however, inaccuracies in the NC and C region contours may cause the conjoint contour to exclude portions of the bladder. To alleviate this problem, we implemented a local contour refinement (LCR) method that exploits model-guided refinement (MGR) and energy-driven wavefront propagation (EDWP). MGR propagates the C region contours if the level set propagation in the C region stops prematurely due to substantial non-uniformity of the contrast. EDWP with regularized energies further propagates the conjoint contours to the correct bladder boundary. EDWP uses changes in energies, smoothness criteria of the contour, and previous slice contour to determine when to stop the propagation, following decision rules derived from training. A data set of 173 cases was collected for this study: 81 cases in the training set (42 lesions, 21 wall thickenings, 18 normal bladders) and 92 cases in the test set (43 lesions, 36 wall thickenings, 13 normal bladders). For all cases, 3D hand segmented contours were obtained as reference standard and used for the evaluation of the computerized segmentation accuracy. For CLASS with LCR, the average volume intersection ratio, average volume error, absolute average volume error, average minimum distance and Jaccard index were 84.2 ± 11.4%, 8.2 ± 17.4%, 13.0 ± 14.1%, 3.5 ± 1.9 mm, 78.8 ± 11.6%, respectively, for the training set and 78.0 ± 14.7%, 16.4 ± 16.9%, 18.2 ± 15

  9. Recurrent bladder carcinoma: clinical and prognostic role of 18 F-FDG PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Alongi, Pierpaolo [San Raffaele G. Giglio Institute, Department of Radiological Sciences, Nuclear Medicine Unit, Cefalu (Italy); Caobelli, Federico [Basel University Hospital, Department of Nuclear Medicine, Basel (Switzerland); Gentile, Roberta; Baldari, Sergio [University of Messina, Nuclear Medicine Unit, Department of Biomedical Sciences and Morphological and Functional Images, Messina (Italy); Stefano, Alessandro; Russo, Giorgio; Gilardi, Maria Carla [IBFM-CNR, Cefalu (Italy); Albano, Domenico [Universita degli Studi di Palermo, DIBIMEF - Sezione di Scienze Radiologiche, Palermo (Italy); Midiri, Massimo [San Raffaele G. Giglio Institute, Department of Radiological Sciences, Nuclear Medicine Unit, Cefalu (Italy); Universita degli Studi di Palermo, DIBIMEF - Sezione di Scienze Radiologiche, Palermo (Italy)

    2017-02-15

    A small number of studies evaluated the detection rate of lesions from bladder carcinoma (BC) of 18 F-FDG PET/CT in the restaging process. However, the prognostic role of FDG PET/CT still remains unclear. The aim of the present study was to evaluate the accuracy, the effect upon treatment decision, and the prognostic value of FDG PET/CT in patients with suspected recurrent BC. Forty-one patients affected by BC underwent FDG PET/CT for restaging purpose. The diagnostic accuracy of visually interpreted FDG PET/CT was assessed compared to histology (n = 8), other diagnostic imaging modalities (contrast-enhanced CT in 38/41 patients and MRI in 15/41) and clinical follow-up (n = 41). Semiquantitative PET values (SUVmax, SUVmean, SUL, MTV, TLG) were calculated using a graph-based method. Progression-free survival (PFS) and overall survival (OS) were assessed by using Kaplan-Meier curves. The risk of progression (hazard ratio, HR) was computed by Cox regression analysis by considering all the available variables. PET was considered positive in 21 of 41 patients. Of these, recurrent BC was confirmed in 20 (95 %). Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of FDG PET/CT were 87 %, 94 %, 95 %, 85 %, 90 %. AUC was 0.9 (95 %IC 0.8-1). Bayesian positive and negative likelihood ratios were 14.5 and 0.13, respectively. FDG PET/CT findings modified the therapeutic approach in 16 patients (modified therapy in 10 PET-positive patients, watch-and-wait in six PET-negative patients). PFS was significantly longer in patients with negative scan vs. those with pathological findings (85 % vs. 24 %, p < 0.05; HR = 12.4; p = 0.001). Moreover, an unremarkable study was associated with a longer OS (88 % vs. 47 % after 2 years and 87 % vs. 25 % after 3 years, respectively, p < 0.05). Standardized uptake value (SUV)max > 6 and total lesion glycolysis (TLG) > 8.5 were recognized as the most accurate thresholds to predict PFS (2-year PFS 62 % for

  10. Radiation dose reduction through combining positron emission tomography/computed tomography (PET/CT) and diagnostic CT in children and young adults with lymphoma.

    Science.gov (United States)

    Qi, Zhihua; Gates, Erica L; O'Brien, Maureen M; Trout, Andrew T

    2018-02-01

    Both [F-18]2-fluoro-2-deoxyglucose positron emission tomography/computed tomography ( 18 F-FDG PET/CT) and diagnostic CT are at times required for lymphoma staging. This means some body segments are exposed twice to X-rays for generation of CT data (diagnostic CT + localization CT). To describe a combined PET/diagnostic CT approach that modulates CT tube current along the z-axis, providing diagnostic CT of some body segments and localization CT of the remaining body segments, thereby reducing patient radiation dose. We retrospectively compared total patient radiation dose between combined PET/diagnostic CT and separately acquired PET/CT and diagnostic CT exams. When available, we calculated effective doses for both approaches in the same patient; otherwise, we used data from patients of similar size. To confirm image quality, we compared image noise (Hounsfield unit [HU] standard deviation) as measured in the liver on both combined and separately acquired diagnostic CT images. We used t-tests for dose comparisons and two one-sided tests for image-quality equivalence testing. Mean total effective dose for the CT component of the combined and separately acquired diagnostic CT exams were 6.20±2.69 and 8.17±2.61 mSv, respectively (Pdose savings with the combined approach was 24.8±17.8% (2.60±2.51 mSv [range: 0.32-4.72 mSv]) of total CT effective dose. Image noise was not statistically significantly different between approaches (12.2±1.8 HU vs. 11.7±1.5 HU for the combined and separately acquired diagnostic CT images, respectively). A combined PET/diagnostic CT approach as described offers dose savings at similar image quality for children and young adults with lymphoma who have indications for both PET and diagnostic CT examinations.

  11. Dental imaging using laminar optical tomography and micro CT

    Science.gov (United States)

    Long, Feixiao; Ozturk, Mehmet S.; Intes, Xavier; Kotha, Shiva

    2014-02-01

    Dental lesions located in the pulp are quite difficult to identify based on anatomical contrast, and, hence, to diagnose using traditional imaging methods such as dental CT. However, such lesions could lead to functional and/or molecular optical contrast. Herein, we report on the preliminary investigation of using Laminar Optical Tomography (LOT) to image the pulp and root canals in teeth. LOT is a non-contact, high resolution, molecular and functional mesoscopic optical imaging modality. To investigate the potential of LOT for dental imaging, we injected an optical dye into ex vivo teeth samples and imaged them using LOT and micro-CT simultaneously. A rigid image registration between the LOT and micro-CT reconstruction was obtained, validating the potential of LOT to image molecular optical contrast deep in the teeth with accuracy, non-invasively. We demonstrate that LOT can retrieve the 3D bio-distribution of molecular probes at depths up to 2mm with a resolution of several hundred microns in teeth.

  12. Evaluation of multidetector computed tomography urography and ultrasonography for diagnosing bladder cancer

    International Nuclear Information System (INIS)

    Knox, M.K.; Cowan, N.C.; Rivers-Bowerman, M.D.; Turney, B.W.

    2008-01-01

    Aim: To evaluate and compare the diagnostic accuracy of multidetector computed tomography urography (CTU) and ultrasonography (US) for diagnosing bladder cancer. Materials and methods: A consecutive series of 143 patients over 40-years of age, presenting with macroscopic haematuria and without urinary tract infection underwent same-day CTU, US, and flexible cystoscopy. CTU and US were independently rated on a five-point scale for the presence of bladder cancer without knowledge of the reference standard of flexible or rigid cystoscopy and/or biopsy results. Diagnostic accuracy was assessed by receiver operating characteristic (ROC) analysis and likelihood ratios. Results: For CTU, a rating of 5 (definitely tumour) was highly specific for bladder cancer (96.5%, 95%CI: 91.3-99%), effectively confirming diagnosis (positive likelihood ratio 25.6, 95%CI: 9.7-67.4). For US, specificity was also high (94.7%, 95%CI: 88.9-98%) with a positive likelihood ratio of 13.1 (95%CI: 5.8-29.6). Sensitivity at this rating was substantially higher for CTU (89.7%, 95%CI: 72.7-97.8%) than US (69%, 95%CI: 49.2-84.7%). Standardized partial area (A z ) under the ROC curve between 95-100% specificity, representing the average sensitivity in this range, was significantly greater (0.88 versus 0.61, p < 0.05) for CTU than US. Conclusion: The specificities of CTU and US for the diagnosis of bladder cancer were similar, but CTU was more sensitive. Although the sensitivity of CTU was not high enough to replace flexible cystoscopy in the diagnostic pathway, the high specificity enables direct referral to rigid cystoscopy, bypassing flexible cystoscopy and expediting diagnosis and treatment in those patients testing positive

  13. Evaluation of multidetector computed tomography urography and ultrasonography for diagnosing bladder cancer

    Energy Technology Data Exchange (ETDEWEB)

    Knox, M.K. [Nuffield Department of Surgery, University of Oxford, Oxford (United Kingdom); Cowan, N.C. [Nuffield Department of Surgery, University of Oxford, Oxford (United Kingdom); Department of Radiology, Churchill Hospital, Oxford OX3 7LJ (United Kingdom)], E-mail: nigel.cowan@nds.ox.ac.uk; Rivers-Bowerman, M.D.; Turney, B.W. [Nuffield Department of Surgery, University of Oxford, Oxford (United Kingdom)

    2008-12-15

    Aim: To evaluate and compare the diagnostic accuracy of multidetector computed tomography urography (CTU) and ultrasonography (US) for diagnosing bladder cancer. Materials and methods: A consecutive series of 143 patients over 40-years of age, presenting with macroscopic haematuria and without urinary tract infection underwent same-day CTU, US, and flexible cystoscopy. CTU and US were independently rated on a five-point scale for the presence of bladder cancer without knowledge of the reference standard of flexible or rigid cystoscopy and/or biopsy results. Diagnostic accuracy was assessed by receiver operating characteristic (ROC) analysis and likelihood ratios. Results: For CTU, a rating of 5 (definitely tumour) was highly specific for bladder cancer (96.5%, 95%CI: 91.3-99%), effectively confirming diagnosis (positive likelihood ratio 25.6, 95%CI: 9.7-67.4). For US, specificity was also high (94.7%, 95%CI: 88.9-98%) with a positive likelihood ratio of 13.1 (95%CI: 5.8-29.6). Sensitivity at this rating was substantially higher for CTU (89.7%, 95%CI: 72.7-97.8%) than US (69%, 95%CI: 49.2-84.7%). Standardized partial area (A{sub z}) under the ROC curve between 95-100% specificity, representing the average sensitivity in this range, was significantly greater (0.88 versus 0.61, p < 0.05) for CTU than US. Conclusion: The specificities of CTU and US for the diagnosis of bladder cancer were similar, but CTU was more sensitive. Although the sensitivity of CTU was not high enough to replace flexible cystoscopy in the diagnostic pathway, the high specificity enables direct referral to rigid cystoscopy, bypassing flexible cystoscopy and expediting diagnosis and treatment in those patients testing positive.

  14. Urinary bladder segmentation in CT urography using deep-learning convolutional neural network and level sets.

    Science.gov (United States)

    Cha, Kenny H; Hadjiiski, Lubomir; Samala, Ravi K; Chan, Heang-Ping; Caoili, Elaine M; Cohan, Richard H

    2016-04-01

    The authors are developing a computerized system for bladder segmentation in CT urography (CTU) as a critical component for computer-aided detection of bladder cancer. A deep-learning convolutional neural network (DL-CNN) was trained to distinguish between the inside and the outside of the bladder using 160 000 regions of interest (ROI) from CTU images. The trained DL-CNN was used to estimate the likelihood of an ROI being inside the bladder for ROIs centered at each voxel in a CTU case, resulting in a likelihood map. Thresholding and hole-filling were applied to the map to generate the initial contour for the bladder, which was then refined by 3D and 2D level sets. The segmentation performance was evaluated using 173 cases: 81 cases in the training set (42 lesions, 21 wall thickenings, and 18 normal bladders) and 92 cases in the test set (43 lesions, 36 wall thickenings, and 13 normal bladders). The computerized segmentation accuracy using the DL likelihood map was compared to that using a likelihood map generated by Haar features and a random forest classifier, and that using our previous conjoint level set analysis and segmentation system (CLASS) without using a likelihood map. All methods were evaluated relative to the 3D hand-segmented reference contours. With DL-CNN-based likelihood map and level sets, the average volume intersection ratio, average percent volume error, average absolute volume error, average minimum distance, and the Jaccard index for the test set were 81.9% ± 12.1%, 10.2% ± 16.2%, 14.0% ± 13.0%, 3.6 ± 2.0 mm, and 76.2% ± 11.8%, respectively. With the Haar-feature-based likelihood map and level sets, the corresponding values were 74.3% ± 12.7%, 13.0% ± 22.3%, 20.5% ± 15.7%, 5.7 ± 2.6 mm, and 66.7% ± 12.6%, respectively. With our previous CLASS with local contour refinement (LCR) method, the corresponding values were 78.0% ± 14.7%, 16.5% ± 16.8%, 18.2% ± 15.0%, 3.8 ± 2.3 mm, and 73.9% ± 13.5%, respectively. The authors

  15. Basics principles of flat detector computed tomography (FD-CT); Grundlagen der Flachdetektor-CT (FD-CT)

    Energy Technology Data Exchange (ETDEWEB)

    Kyriakou, Y.; Struffert, T.; Doerfler, A.; Kalender, W.A. [Universitaet Erlangen-Nuernberg, Institut fuer Medizinische Physik, Erlangen (Germany)

    2009-09-15

    Flat detectors (FDs) have been developed for use in radiography and fluoroscopy to replace standard X-ray film, film-screen combinations and image intensifiers (II). In comparison to X-ray film and II, FD technology offers higher dynamic range, dose reduction, fast digital readout and the possibility for dynamic acquisitions of image series, yet keeping to a compact design. It appeared logical to employ FD designs also for computed tomography (CT) imaging. FDCT has meanwhile become widely accepted for interventional and intra-operative imaging using C-arm systems. Additionally, the introduction of FD technology was a milestone for soft-tissue CT imaging in the interventional suite which was not possible with II systems in the past. This review focuses on technical and performance issues of FD technology and its wide range of applications for CT imaging. FDCT is not aimed at challenging standard clinical CT as regards to the typical diagnostic examinations, but it has already proven unique for a number of dedicated CT applications offering distinct practical advantages, above all the availability of immediate CT imaging during an intervention. (orig.) [German] Flachdetektoren (FD) sind fuer die Anwendung in der Radiographie und Fluoroskopie entwickelt worden, um die damaligen Standards - Film-Folien-Kombinationen (FFK) und Bildverstaerker (BV) - zu ersetzen. Im Vergleich zu FFK und BV bietet die FD-Technologie eine hoehere Dynamik, Verzerrungsfreiheit und eine gesteigerte Dosiseffizienz. Weitere Vorteile sind die Anfertigung Serienaufnahmen, eine sofortige Digitalausgabe und eine kompakte Bauweise. Dies legt auch eine Anwendung von Flachdetektoren in der Computertomographie (CT) nahe. Inzwischen ist die FD-CT weitgehend in der interventionellen und intraoperativen Bildgebung etabliert - meist als C-Bogen-System. Die FD-Technologie hat erstmals die Weichteilbildgebung in der interventionellen Suite ermoeglicht, was mit BV-Systemen nicht moeglich war. Diese

  16. Positron emission tomography/computed tomography (PET/CT) and CT for N staging of non-small cell lung cancer.

    Science.gov (United States)

    Vegar Zubović, Sandra; Kristić, Spomenka; Hadžihasanović, Besima

    2017-08-01

    Aim The aim of this study is to investigate the possibilities of non-invasive diagnostic imaging methods, positron emission tomography/computed tomography (PET/CT) and CT, in clinical N staging of non-small cell lung cancer (NSCLC). Methods Retrospective clinical study included 50 patients with diagnosed NSCLC who have undergone PET/CT for the purpose of disease staging. The International association for the study of lung cancer (IASLC) nodal mapping system was used for analysis of nodal disease. Data regarding CT N-staging and PET/CT Nstaging were recorded. Two methods were compared using χ2 test and Spearman rank correlation coefficient. Results Statistical analysis showed that although there were some differences in determining the N stage between CT and PET/CT, these methods were in significant correlation. CT and PET/CT findings established the same N stage in 74% of the patients. In five patients based on PET/CT findings the staging was changed from operable to inoperable, while in four patients staging was changed from inoperable to operable. Conclusion PET/CT and CT are noninvasive methods that can be reliably used for N staging of NSCLC. Copyright© by the Medical Assotiation of Zenica-Doboj Canton.

  17. Target localization on standard axial images in computed tomography (CT) stereotaxis for functional neurosurgery - a technical note

    International Nuclear Information System (INIS)

    Patil, A.-A.

    1986-01-01

    A simple technique for marking functional neurosurgery target on computed tomography (CT) axial image is described. This permits the use of standard axial image for computed tomography (CT) stereotaxis in functional neurosurgery. (Author)

  18. Paraneoplastic retinopathy associated with occult bladder cancer

    DEFF Research Database (Denmark)

    Nivean, M; Muttuvelu, Danson V; Afzelius, Pia Maria Tullia

    2016-01-01

    The aim was to report the first case of cancer-associated retinopathy (CAR) presenting before bladder cancer diagnosis. A 71-year-old woman with a history of bilateral vision loss underwent subsequent complete ophthalmic examination include a fluorescein angiography, full-field electroretinogram...... (ERG), serology including serum antibodies for CAR, and positron emission tomography-computed tomography (PET-CT) scan. The patient was diagnosed with bladder carcinoma revealed by PET-CT. Timely recognition of this entity may be crucial for an increased patient survival thus adult onset progressive...

  19. [18F]Fluorodeoxyglucose (FDG)-Positron Emission Tomography (PET)/Computed Tomography (CT) in Suspected Recurrent Breast Cancer

    DEFF Research Database (Denmark)

    Hildebrandt, Malene Grubbe; Gerke, Oke; Baun, Christina

    2016-01-01

    PURPOSE: To prospectively investigate the diagnostic accuracy of [(18)F]fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) with dual-time-point imaging, contrast-enhanced CT (ceCT), and bone scintigraphy (BS) in patients with suspected breast cancer recurrence....... PATIENTS AND METHODS: One hundred women with suspected recurrence of breast cancer underwent 1-hour and 3-hour FDG-PET/CT, ceCT, and BS within approximately 10 days. The study was powered to estimate the precision of the individual imaging tests. Images were visually interpreted using a four......-point assessment scale, and readers were blinded to other test results. The reference standard was biopsy along with treatment decisions and clinical follow-up (median, 17 months). RESULTS: FDG-PET/CT resulted in no false negatives and fewer false positives than the other imaging techniques. Accuracy of results...

  20. Segmentation of inner and outer bladder wall using deep-learning convolutional neural network in CT urography

    Science.gov (United States)

    Gordon, Marshall; Hadjiiski, Lubomir; Cha, Kenny; Chan, Heang-Ping; Samala, Ravi; Cohan, Richard H.; Caoili, Elaine M.

    2017-03-01

    We are developing a computerized system for detection of bladder cancer in CT urography. In this study, we used a deep-learning convolutional neural network (DL-CNN) to segment the bladder wall. This task is challenging due to differences in the wall between the contrast and non-contrast-filled regions, significant variations in appearance, size, and shape of the bladder among cases, overlap of the prostate with the bladder wall, and the wall being extremely thin compared to the overall size of the bladder. We trained a DL-CNN to estimate the likelihood that a given pixel would be inside the wall of the bladder using neighborhood information. A segmented bladder wall was then obtained using level sets with this likelihood map as a term in the level set energy formulation to obtain contours of the inner and outer bladder walls. The accuracy of the segmentation was evaluated by comparing the segmented wall outlines to hand outlines for a set of 79 training cases and 15 test cases using the average volume intersection % as the metric. For the training set, the inner wall achieved an average volume intersection of 90.0+/-8.7% and the outer wall achieved 93.7+/-3.9%. For the test set, the inner wall achieved an average volume intersection of 87.6+/-7.6% and the outer wall achieved 87.2+/-9.3%. The results show that the DL-CNN with level sets was effective in segmenting the inner and outer bladder walls.

  1. Three dimensional computed tomography (CT) algorithms for a planar object

    International Nuclear Information System (INIS)

    Chi, Yong Ki

    2007-02-01

    Recently modern X-ray computed tomography (CT) scanner is rapidly moving towards cone-beam geometry. One of the important advantages of the cone-beam CT is its fast volumetric scanning capability. Also it provides the opportunity for tomographic image reconstruction with magnified resolution. This opportunity is applicable for Emission CT (ECT) scanner with a convergent collimator, which functions as cone beam geometry. However, in a cone-beam image reconstruction, current existing reconstruction algorithms put limitations from long object problems due to the nature of insufficient data or limited source scanning. Therefore, the algorithms that is based on cone-beam geometry and free from limited source scanning highly demanded these days. In this study, for planar object, we have developed full and half-scan algorithms based on approximated cone-beam back-projection. For solving long object problems, many other reconstruction algorithms have been adopted by several helical CT scanners that are composed of a micro-focus X-ray tube and flat panel detector. Although these efforts make the long object problem solved, it remains for planar object as ever due to limited source scanning such as non-isocentric circular orbit. Prior to the algorithmic development, we report digital tomosynthesis (DT) called laminography using geometric projection methods for reconstructing arbitrary cross-section images as well as three dimensional laminography images for cone-beam CT. Digital laminography are advantageous in terms of temporal resolution, and widely used only with a few number of projection data on cone-beam geometry. While existing laminography algorithms use the geometric projection methods, in this dissertation we substitute back-projection technique instead of the geometric projection. Both of laminography without filtering and weighting steps have similar results except for the complexity between their algorithms but it makes the blurring and other severe artifacts in

  2. Use of computed tomography scout film and Hounsfield unit of computed tomography scan in predicting the radio-opacity of urinary calculi in plain kidney, ureter and bladder radiographs.

    Science.gov (United States)

    Chua, Michael E; Gomez, Odina R; Sapno, Lorelei D; Lim, Steve L; Morales, Marcelino L

    2014-07-01

    The objective of this study is to determine the diagnostic utility of computed tomography (CT)- scout film with an optimal non-contrast helical CT scan Hounsfield unit (HU) in predicting the appearance of urinary calculus in the plain kidneys, ureter, urinary bladder (KUB)-radiograph. A prospective cross-sectional study was executed and data were collected from June 2007 to June 2012 at a tertiary hospital. The included subjects were diagnosed to have value, CT-scout film and KUB radiograph appearance were recorded independently by two observers. Univariate logistic analysis with receiver operating characteristic curve was generated to determine the best cut-off HU value of urolithiases not identified in CT-scout film, but determined radio-opaque in KUB X-ray. Subsequently, its sensitivity, specificity, predictive values and likelihood ratios were calculated. Statistical significance was set at P value of 0.05 or less. Two hundred and three valid cases were included. 73 out of 75 CT-scout film detected urolithiasis were identified on plain radiograph and determined as radio-opaque. The determined best cut off value of HU utilized for prediction of radiographic characteristics was 630HU at which urinary calculi were not seen at CT-scout film and were KUB X-ray radio-opaque. The set HU cut-off was established of ideal accuracy with an overall sensitivity of 82.2%, specificity of 96.9% and a positive predictive value of 96.5% and negative predictive value of 83.5%. Urolithiases identified on the CT-scout film were also seen as radiopaque on the KUB radiograph while those stones not visible on the CT-scout film, but above the optimal HU cut-off value of 630 are also likely to be radiopaque.

  3. 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.

  4. Virtual cystoscopy, computed tomography urography and optical cystoscopy for the detection and follow-up for bladder cancer.

    Science.gov (United States)

    Ibáñez Muñoz, D; Quintana Martínez, I; Fernández Militino, A; Sánchez Zalabardo, D; Sarria Octavio de Toledo, L; Cozcolluela Cabrejas, R

    To evaluate the utility of virtual cystoscopy (VC) performed with CT urography in patients being studied under gross hematuria or patients being followed-up after a previous bladder cancer and compare the results with those obtained with gold standard technique (optical cystoscopy). Retrospective study of 117 patients who were referred for VC by the Urology Department between May 2014 and May 2015. Those patients presented with gross hematuria or they were previously treated patients from bladder cancer being followed up. These patients were evaluated with MDCT and virtual cystoscopy after distending the bladder with air. The results were compared with those obtained with optical cystoscopy which was performed no more than a week after. The global sensitivity and specificity of VC were 81,8 and 92,1%. Aditional findings detected in CT urography were an aortic dissection, urinary lithiasis and colonic metastasis. VC seems an useful technique in the diagnosis and follow-up for bladder cancer with a good correlation with OC. The main limitations are the impossibility of biopsy during the procedure and the detection of erythematous lesions. Collateral findings can be detected performed with CT urography although the high radiation exposure does not recommend their combined use. Copyright © 2017 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

  5. Perirenal fat stranding on CT: is there an association with bladder outlet obstruction?

    Science.gov (United States)

    Han, Na Y; Sung, Deuk J; Kim, Min J; Park, Beom J; Sim, Ki C; Cho, Sung B

    2016-07-01

    To determine the association between perirenal fat stranding (PFS) on CT and bladder outlet obstruction (BOO). CT scans from 122 patients who had undergone urodynamic study for lower urinary tract symptoms (LUTS) were registered after exclusion of patients with renal or retroperitoneal disease. Images were independently reviewed by two radiologists and compared with those of 244 age- and sex-matched control patients without LUTS. The PFS severity was scored on a four-point scale, and the interobserver agreement was assessed with kappa statistics. The severity score and incidence was compared between the groups, and the association with baseline characteristics was analyzed. For the LUTS group, an association between PFS severity and urodynamic and laboratory data was evaluated. PFS was more frequent and more severe in the LUTS group than in the control group (p-value < 0.001); its presence was significantly associated with male gender and older age (p-value < 0.001). PFS was predominantly bilateral in both groups (80.1-93.2%). In the LUTS group, PFS severity scores were significantly correlated with the maximum flow rate, maximum detrusor pressure and estimated glomerular filtration rate (p-value < 0.001). Interobserver agreements were excellent for PFS presence (κ = 0.883) and severity (κ = 0.816). Severe PFS was observed in older, male patients with LUTS. PFS severity was associated with the degree of BOO and impaired renal function. Recognition of PFS on the CT scan may warrant further evaluation of BOO and appropriate management to prevent renal impairment.

  6. On the possibility of time-lapse ultrahigh-resolution optical coherence tomography for bladder cancer grading

    Science.gov (United States)

    Yuan, Zhijia; Chen, Bai; Ren, Hugang; Pan, Yingtian

    2009-09-01

    It has been recently demonstrated that the cellular details of bladder epithelium embedded in speckle noise can be uncovered with time-lapse ultrahigh-resolution optical coherence tomography (TL-uOCT) by proper time-lapse frame averaging that takes advantage of cellular micromotion in fresh biological tissue ex vivo. Here, spectral-domain 3-D TL-uOCT is reported to further improve the image fidelity, and new experimental evidence is presented to differentiate normal and cancerous nuclei of rodent bladder epithelia. Results of animal cancer study reveal that despite a slight overestimation (e.g., cancerous (e.g., high-grade DN''~13 μm) urothelia, which may potentially be very useful for enhancing the diagnosis of nonpapillary bladder cancer. More animal study is being conducted to examine the utility to differentiate hyperplasia, dysplasia, and carcinoma in situ.

  7. ACR-SPR-STR Practice Parameter for the Performance of Cardiac Positron Emission Tomography - Computed Tomography (PET/CT) Imaging.

    Science.gov (United States)

    Subramaniam, Rathan M; Janowitz, Warren R; Johnson, Geoffrey B; Lodge, Martin A; Parisi, Marguerite T; Ferguson, Mark R; Hellinger, Jeffrey C; Gladish, Gregory W; Gupta, Narainder K

    2017-12-01

    This clinical practice parameter has been developed collaboratively by the American College of Radiology (ACR), the Society for Pediatric Radiology (SPR), and the Society of Thoracic Radiology (STR). This document is intended to act as a guide for physicians performing and interpreting positron emission tomography-computed tomography (PET/CT) of cardiac diseases in adults and children. The primary value of cardiac PET/CT imaging include evaluation of perfusion, function, viability, inflammation, anatomy, and risk stratification for cardiac-related events such as myocardial infarction and death. Optimum utility of cardiac PET/CT is achieved when images are interpreted in conjunction with clinical information and laboratory data. Measurement of myocardial blood flow, coronary flow reserve and detection of balanced ischemia are significant advantages of cardiac PET perfusion studies. Increasingly cardiac PET/CT is used in diagnosis and treatment response assessment for cardiac sarcoidosis.

  8. Evaluation of dosimetric techniques in positrons emission tomography and computerized tomography (PET/CT); Avaliacao de tecnicas dosimetricas em tomografia por emissao de positrons e tomografia computadorizada (PET/CT)

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, Gabriella Montezano

    2014-09-01

    Among diagnostic techniques PET/CT is one of those with the highest dose delivery to the patient as a cause of external exposure to X-rays, and the use of a radiopharmaceutical that results in a high energy gamma emission. The dosimetry of these two components becomes important in order to optimize and justify the technique. Various dosimetric techniques are found in literature without a consensus of the best to use. With the advances in technological and consequent equipment configuration changes, upgrades and variation in methodologies, particularly in computed tomography, a standardization of these techniques is required. Previous studies show that CT is responsible for 70 % of the dose delivered to the patient in PET/CT examinations. Thus, many researchers have been focused on CT dose optimization protocols studies. This work analyzes the doses involved in a PET/CT oncology protocol by using an Alderson female anthropomorphic phantom in a public hospital of Rio de Janeiro city. The dose estimate for PET examination resulting from the use of {sup 18}F - FDG radiopharmaceutical was conducted through dose factors published in ICRP 106; the dose for CT was estimated and compared by calculation of the absorbed doses to patients according to four methods: thermoluminescent dosimetry (TL0100) distributed in critical organs of the Alderson phantom; measurements of CTOI according to AAPM number 96; correction factor for effective diameter SSOE (AAPM Number 204); and simulation by ImPACT program For CT, the results in terms of effective dose presented (TLO, CTOI and ImPACT) ± 5 % maximum variations between methodologies. Considering medium absorbed dose (TLO, SSOE and ImPACT) the results differed in ± 7 % from each other. These findings demonstrate that parameters provided by the manufacturer on the console can be used to have a primary approach of both, absorbed and effective doses to the patient since that a quality assurance program of these parameters are adopted

  9. The sensitivity of computed tomography (CT) scans in detecting trauma: are CT scans reliable enough for courtroom testimony?

    Science.gov (United States)

    Molina, D Kimberley; Nichols, Joanna J; Dimaio, Vincent J M

    2007-09-01

    Rapid and accurate recognition of traumatic injuries is extremely important in emergency room and surgical settings. Emergency departments depend on computed tomography (CT) scans to provide rapid, accurate injury assessment. We conducted an analysis of all traumatic deaths autopsied at the Bexar County Medical Examiner's Office in which perimortem medical imaging (CT scan) was performed to assess the reliability of the CT scan in detecting trauma with sufficient accuracy for courtroom testimony. Cases were included in the study if an autopsy was conducted, a CT scan was performed within 24 hours before death, and there was no surgical intervention. Analysis was performed to assess the correlation between the autopsy and CT scan results. Sensitivity, specificity, positive predictive value, and negative predictive value were defined for the CT scan based on the autopsy results. The sensitivity of the CT scan ranged from 0% for cerebral lacerations, cervical vertebral body fractures, cardiac injury, and hollow viscus injury to 75% for liver injury. This study reveals that CT scans are an inadequate detection tool for forensic pathologists, where a definitive diagnosis is required, because they have a low level of accuracy in detecting traumatic injuries. CT scans may be adequate for clinicians in the emergency room setting, but are inadequate for courtroom testimony. If the evidence of trauma is based solely on CT scan reports, there is a high possibility of erroneous accusations, indictments, and convictions.

  10. Inter-laboratory comparison of medical computed tomography (CT) scanners for industrial applications in the slaughterhouses

    DEFF Research Database (Denmark)

    Christensen, Lars Bager; Angel, Jais Andreas Breusch

    2013-01-01

    Using computed tomography (CT) in the calibration of online grading equipment has been demonstrated to be beneficial over the last years by several institutions using medical CT scanners. The difference in makes and models calls for a standardized (and calibrated) method to be able to quantify di...

  11. Micro computed tomography (CT) scanned anatomical gateway to insect pest bioinformatics

    Science.gov (United States)

    An international collaboration to establish an interactive Digital Video Library for a Systems Biology Approach to study the Asian citrus Psyllid and psyllid genomics/proteomics interactions is demonstrated. Advances in micro-CT, digital computed tomography (CT) scan uses X-rays to make detailed pic...

  12. Dosimetric evaluation of rectum and bladder using image-based CT planning and orthogonal radiographs with ICRU 38 recommendations in intracavitary brachytherapy

    Directory of Open Access Journals (Sweden)

    Jamema Swamidas

    2008-01-01

    Full Text Available The purpose is to compare CT-based dosimetry with International Commission on Radiation Units and Measurements (ICRU 38 bladder and rectum reference points in patients of carcinoma of uterine cervix treated with intracavitary brachytherapy (ICA. Twenty-two consecutive patients were evaluated. Orthogonal radiographs and CT images were acquired and transferred to PLATO planning system. Bladder and rectal reference points were identified according to ICRU 38 recommendations. Dosimetry was carried out based on Manchester system. Patient treatment was done using 192 Iridium high dose rate (HDR remote after-loading machine based on the conventional radiograph-based dosimetry. ICRU rectal and bladder point doses from the radiograph plans were compared with D 2 , dose received by 2 cm 3 of the organ receiving maximum dose from CT plan. V 2 , volume of organ receiving dose more than the ICRU reference point, was evaluated. The mean (±standard deviation volume of rectum and bladder was 60 (±28 cm 3 and 138 (±41 cm 3 respectively. The mean reference volume in radiograph and CT plan was 105 (±7 cm 3 and 107 (±7 cm 3 respectively. It was found that 6 (±4 cm3 of rectum and 16 (±10 cm 3 of bladder received dose more than the prescription dose. V2 of rectum and bladder was 7 (±1.7 cm 3 and 20.8 (±6 cm 3 respectively. Mean D 2 of rectum and bladder was found to be 1.11 (±0.2 and 1.56 (±0.6 times the mean ICRU reference points respectively. This dosimteric study suggests that comparison of orthogonal X-ray-based and CT-based HDR ICA planning is feasible. ICRU rectal point dose correlates well with maximum rectal dose, while ICRU bladder point underestimates the maximum bladder dose.

  13. Computed tomography (CT)-compatible remote center of motion needle steering robot : Fusing CT images and electromagnetic sensor data

    NARCIS (Netherlands)

    Shahriari, Navid; Heerink, Wout; van Katwijk, Tim; Hekman, Edsko E. G.; Oudkerk, Matthijs; Misra, Sarthak

    Lung cancer is the most common cause of cancer-related death, and early detection can reduce the mortality rate. Patients with lung nodules greater than 10 mm usually undergo a computed tomography (CT) guided biopsy. However, aligning the needle with the target is difficult and the needle tends to

  14. To CT or not to CT? The influence of computed tomography on the diagnosis of appendicitis in obese pediatric patients

    Science.gov (United States)

    Roy, Haven; Burbridge, Brent

    2015-01-01

    Background Appendicitis is a common pediatric query. However, obesity often results in nondiagnostic ultrasounds and increased likelihood of abdominal computed tomography (CT). Concern regarding radiation exposure led the Canadian Association of Radiologists to recommend foregoing CT when ultrasounds are nondiagnostic and clinical suspicion is high. We evaluated this recommendation by quantifying the influence of CT on the diagnosis of pediatric appendicitis. Methods We performed a 2-year retrospective case series of children presenting with suspected appendicitis. We stratified patients by weight (obese v. nonobese) and pediatric appendicitis score (PAS) and examined how often they received abdominal CT, why they received it, and its influence on diagnosis. Results Of 223 patients (84 obese, 139 nonobese), 54 received CT. Obese patients received CTs more frequently than nonobese patients (29% v. 22%). The most common reason for CT was a nondiagnostic ultrasound (75% in obese, 80% in nonobese patients). Sixty-five percent of CTs obtained after nondiagnostic ultrasounds confirmed the initial diagnosis, but the rates were 80% and 50%, respectively, when only obese and only nonobese patients were considered. Obese patients were 4 times more likely to have a CT confirming their initial appendicitis diagnosis. Conclusion Because obese patients are more likely than nonobese patients to have a CT that confirms appendicitis, when treating an obese pediatric patient with suspected appendicitis and a nondiagnostic ultrasound, surgeons with a high clinical suspicion should strongly consider foregoing CT and proceeding with treatment. PMID:26011850

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

    Energy Technology Data Exchange (ETDEWEB)

    Wognum, S., E-mail: s.wognum@gmail.com; Heethuis, S. E.; Bel, A. [Department of Radiation Oncology, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam (Netherlands); Rosario, T. [Department of Radiation Oncology, VU University Medical Center, De Boelelaan 1117, 1081 HZ Amsterdam (Netherlands); Hoogeman, M. S. [Department of Radiation Oncology, Erasmus MC Cancer Institute, Erasmus Medical Center, Groene Hilledijk 301, 3075 EA Rotterdam (Netherlands)

    2014-07-15

    Purpose: The spatial accuracy of deformable image registration (DIR) is important in the implementation of image guided adaptive radiotherapy techniques for cancer in the pelvic region. Validation of algorithms is best performed on phantoms with fiducial markers undergoing controlled large deformations. Excised porcine bladders, exhibiting similar filling and voiding behavior as human bladders, provide such an environment. The aim of this study was to determine the spatial accuracy of different DIR algorithms on CT images ofex vivo porcine bladders with radiopaque fiducial markers applied to the outer surface, for a range of bladder volumes, using various accuracy metrics. Methods: Five excised porcine bladders with a grid of 30–40 radiopaque fiducial markers attached to the outer wall were suspended inside a water-filled phantom. The bladder was filled with a controlled amount of water with added contrast medium for a range of filling volumes (100–400 ml in steps of 50 ml) using a luer lock syringe, and CT scans were acquired at each filling volume. DIR was performed for each data set, with the 100 ml bladder as the reference image. Six intensity-based algorithms (optical flow or demons-based) implemented in theMATLAB platform DIRART, a b-spline algorithm implemented in the commercial software package VelocityAI, and a structure-based algorithm (Symmetric Thin Plate Spline Robust Point Matching) were validated, using adequate parameter settings according to values previously published. The resulting deformation vector field from each registration was applied to the contoured bladder structures and to the marker coordinates for spatial error calculation. The quality of the algorithms was assessed by comparing the different error metrics across the different algorithms, and by comparing the effect of deformation magnitude (bladder volume difference) per algorithm, using the Independent Samples Kruskal-Wallis test. Results: The authors found good structure

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

    International Nuclear Information System (INIS)

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

    2014-01-01

    Purpose: The spatial accuracy of deformable image registration (DIR) is important in the implementation of image guided adaptive radiotherapy techniques for cancer in the pelvic region. Validation of algorithms is best performed on phantoms with fiducial markers undergoing controlled large deformations. Excised porcine bladders, exhibiting similar filling and voiding behavior as human bladders, provide such an environment. The aim of this study was to determine the spatial accuracy of different DIR algorithms on CT images ofex vivo porcine bladders with radiopaque fiducial markers applied to the outer surface, for a range of bladder volumes, using various accuracy metrics. Methods: Five excised porcine bladders with a grid of 30–40 radiopaque fiducial markers attached to the outer wall were suspended inside a water-filled phantom. The bladder was filled with a controlled amount of water with added contrast medium for a range of filling volumes (100–400 ml in steps of 50 ml) using a luer lock syringe, and CT scans were acquired at each filling volume. DIR was performed for each data set, with the 100 ml bladder as the reference image. Six intensity-based algorithms (optical flow or demons-based) implemented in theMATLAB platform DIRART, a b-spline algorithm implemented in the commercial software package VelocityAI, and a structure-based algorithm (Symmetric Thin Plate Spline Robust Point Matching) were validated, using adequate parameter settings according to values previously published. The resulting deformation vector field from each registration was applied to the contoured bladder structures and to the marker coordinates for spatial error calculation. The quality of the algorithms was assessed by comparing the different error metrics across the different algorithms, and by comparing the effect of deformation magnitude (bladder volume difference) per algorithm, using the Independent Samples Kruskal-Wallis test. Results: The authors found good structure

  17. Usefulness of computed tomography (CT) in the diagnosis of portosystemic collaterals in liver cirrhosis

    International Nuclear Information System (INIS)

    Tsukune, Yoshihiko

    1984-01-01

    This study assesses the usefulness of computed tomography (CT) in the diagnosis of portosystemic collaterals in liver cirrhosis. Seventy-eight patients with liver cirrhosis underwent both CT and angiography. Comparison was made between CT and angiography on eleven types of collaterals, and many of them were demonstrated on CT scans better than angio. Especially, esophageal varices, paraesophageal varices, umbilical pathway and caput medusa were diagnostic on CT scans. Gastrorenal collaterals, splenorenal collaterals, retroperitoneal pathway are also well demonstrated. Dilatation of azygos systems and small veins in the liver surface are only observed on CT scans. However, coronary varices and short gastric varices are well diagnostic in angiography. But considering all types of collaterals, it was stressed that angiography can be eliminated by CT in evaluation of collaterals in liver cirrhosis. (author)

  18. Inter-laboratory comparison of medical computed tomography (CT) scanners for industrial applications in the slaughterhouses

    DEFF Research Database (Denmark)

    Christensen, Lars Bager; Angel, Jais Andreas Breusch

    2013-01-01

    Using computed tomography (CT) in the calibration of online grading equipment has been demonstrated to be beneficial over the last years by several institutions using medical CT scanners. The difference in makes and models calls for a standardized (and calibrated) method to be able to quantify......, conventionally recognized to be challenging to medical CT scanners. The web based classification software PigClassWeb has been demonstrated to be a convenient way of handling and comparing CT data in a transparent way, across regions and over time. The phantom set may be used to compare regional differences...

  19. [Application of computed tomography (CT) examination for forensic medicine].

    Science.gov (United States)

    Urbanik, Andrzej; Chrzan, Robert

    2013-01-01

    The aim of the study is to present a own experiences in usage of post mortem CT examination for forensic medicine. With the help of 16-slice CT scanner 181 corpses were examined. Obtained during acquisition imaging data are later developed with dedicated programmes. Analyzed images were extracted from axial sections, multiplanar reconstructions as well as 3D reconstructions. Gained information helped greatly when classical autopsy was performed by making it more accurate. A CT scan images recorded digitally enable to evaluate corpses at any time, despite processes of putrefaction or cremation. If possible CT examination should precede classical autopsy.

  20. Adaptive-Predictive Organ Localization Using Cone-Beam Computed Tomography for Improved Accuracy in External Beam Radiotherapy for Bladder Cancer

    International Nuclear Information System (INIS)

    Lalondrelle, Susan; Huddart, Robert; Warren-Oseni, Karole; Hansen, Vibeke Nordmark; McNair, Helen; Thomas, Karen; Dearnaley, David; Horwich, Alan; Khoo, Vincent

    2011-01-01

    Purpose: To examine patterns of bladder wall motion during high-dose hypofractionated bladder radiotherapy and to validate a novel adaptive planning method, A-POLO, to prevent subsequent geographic miss. Methods and Materials: Patterns of individual bladder filling were obtained with repeat computed tomography planning scans at 0, 15, and 30 minutes after voiding. A series of patient-specific plans corresponding to these time-displacement points was created. Pretreatment cone-beam computed tomography was performed before each fraction and assessed retrospectively for adaptive intervention. In fractions that would have required intervention, the most appropriate plan was chosen from the patient's 'library,' and the resulting target coverage was reassessed with repeat cone-beam computed tomography. Results: A large variation in patterns of bladder filling and interfraction displacement was seen. During radiotherapy, predominant translations occurred cranially (maximum 2.5 cm) and anteriorly (maximum 1.75 cm). No apparent explanation was found for this variation using pretreatment patient factors. A need for adaptive planning was demonstrated by 51% of fractions, and 73% of fractions would have been delivered correctly using A-POLO. The adaptive strategy improved target coverage and was able to account for intrafraction motion also. Conclusions: Bladder volume variation will result in geographic miss in a high proportion of delivered bladder radiotherapy treatments. The A-POLO strategy can be used to correct for this and can be implemented from the first fraction of radiotherapy; thus, it is particularly suited to hypofractionated bladder radiotherapy regimens.

  1. The clinical usefulness of 18F-fluorodeoxyglucose positron emission tomography-computed tomography (PET-CT) in follow-up of curatively resected pancreatic cancer patients.

    Science.gov (United States)

    Jung, Woohyun; Jang, Jin-Young; Kang, Mee Joo; Chang, Ye Rim; Shin, Yong Chan; Chang, Jihoon; Kim, Sun-Whe

    2016-01-01

    Computed tomography and serum tumor markers have limited value in detecting recurrence after curative surgery of pancreatic cancer. This study evaluated the clinical utility of 18F-fluorodeoxyglucose positron emission tomography-computed tomography (PET-CT) in diagnosing recurrence. One hundred ten patients underwent curative resection of pancreatic cancer were enrolled. The diagnostic value of abdominal computed tomography (CT), PET-CT and serum carbohydrate antigen (CA) 19-9 concentration were compared. The prognostic value of SUVmax on PET-CT was evaluated. PET-CT showed relatively higher sensitivity (84.5% vs. 75.0%) and accuracy (84.5% vs. 74.5%) than CT, whereas PET-CT plus CT showed greater sensitivity (97.6%) and accuracy (90.0%) than either alone. In detecting distant recurrences, PET-CT showed higher sensitivity (83.1% vs. 67.7%) than CT. Nineteen patients showed recurrences only on PET-CT, with eleven having invisible or suspected benign lesions on CT, and eight had recurrences in areas not covered by CT. SUVmax over 3.3 was predictive of poor survival after recurrence. PET-CT in combination with CT improves the detection of recurrence. PET-CT was especially advantageous in detecting recurrences in areas not covered by CT. If active post-operative surveillance after curative resection of pancreatic cancer is deemed beneficial, then it should include PET-CT combined with CT. Copyright © 2015 International Hepato-Pancreato-Biliary Association Inc. Published by Elsevier Ltd. All rights reserved.

  2. Laparoscopic Scar: a mimicker of Sister Mary Joseph's nodule on positron emission tomography/CT

    International Nuclear Information System (INIS)

    Setty, B.; Blake, M.A.; Holalkere, N.S.; Blaszkowsky, L.S.; Fischman, A.

    2006-01-01

    Positron emission tomography/CT is an established imaging method in the diagnosis and staging of cancers. 18 F -fluoro-2-deoxy-D-glucose (FDG) is the most commonly used radiotracer in positron emission tomography/CT. It is a tumour viability agent and usually its uptake within a lesion reflects the presence of a viable tumour tissue. However, false-positive FDG uptake is known to occur in benign processes of either inflammatory or infectious aetiology. We describe FDG uptake at the site of laparoscopic scar that mimicked Sister Mary Joseph's nodule in a patient with gastric adenocarcinoma. Here, the knowledge of the patient's history and subtle imaging findings helped in accurate staging of the patient. In this case report, we emphasize the value of the knowledge of the patient history and awareness of different pitfalls of FDG to achieve a correct diagnosis on positron emission tomography/CT

  3. Results of diagnosis of pancreatic cancer by computed tomography (CT)

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, K.; Okuaki, K.; Ito, M.; Katakura, T.; Suzuki, K. (Fukushima Medical Coll. (Japan))

    1981-08-01

    Results of examination of pancreatic diseases, especially pancreatic cancer, conducted by CT during the past 3 years are summarized. The EMI CT Type 5000 or 5005 were used. During the 3 years from September 1976 to August 1979, a total of 1961 patients were examined by CT, and the upper abdomen was examined in 772 of these patients. In 97 patients, positive findings were obtained in the CT image of the pancreas. In 52 of these patients, the findings were confirmed operatively or by autopsy. Though cancer of the pancreas was diagnosed by CT in 30 patients, it was confirmed in 20 by surgical operation and in 1 by autopsy. Of the 9 misdiagnosed cases, 4 were cases of infiltration of the pancreas by carcinoma of the stomach or bile duct, and the other 5 were one case each of lipoma of the abdominal wall, normal pancreas, hyperplasia of Langerhans's islets of the pancreas tail, abscess between the pancreas and the posterior wall of the stomach, and choledocholithiasis. A case diagnosed by CT as cholelithiasis was a carcinoma measuring 5 x 5 x 6 cm located on the head of the pancreas, complicated by choledocholithiasis. The 22 patients with carcinoma of the pancreas were 9 with lesions less than 3.5 x 3.0 x 3.0 cm in size who could be radically operated, 6 who underwent exploratory laparotomy or autopsy, and 7 in whom operation was impossible. False negative and false positive CT results are also discussed.

  4. Results of diagnosis of pancreatic cancer by computed tomography (CT)

    International Nuclear Information System (INIS)

    Kimura, Kazue; Okuaki, Koji; Ito, Masami; Katakura, Toshihiko; Suzuki, Kenji

    1981-01-01

    Results of examination of pancreatic diseases, especially pancreatic cancer, conducted by CT during the past 3 years are summarized. The EMI CT Type 5000 or 5005 were used. During the 3 years from September 1976 to August 1979, a total of 1961 patients were examined by CT, and the upper abdomen was examined in 772 of these patients. In 97 patients, positive findings were obtained in the CT image of the pancreas. In 52 of these patients, the findings were confirmed operatively or by autopsy. Though cancer of the pancreas was diagnosed by CT in 30 patients, it was confirmed in 20 by surgical operation and in 1 by autopsy. Of the 9 misdiagnosed cases, 4 were cases of infiltration of the pancreas by carcinoma of the stomach or bile duct, and the other 5 were one case each of lipoma of the abdominal wall, normal pancreas, hyperplasia of Langerhans's islets of the pancreas tail, abscess between the pancreas and the posterior wall of the stomach, and choledocholithiasis. A case diagnosed by CT as cholelithiasis was a carcinoma measuring 5 x 5 x 6 cm located on the head of the pancreas, complicated by choledocholithiasis. The 22 patients with carcinoma of the pancreas were 9 with lesions less than 3.5 x 3.0 x 3.0 cm in size who could be radically operated, 6 who underwent exploratory laparotomy or autopsy, and 7 in whom operation was impossible. False negative and false positive CT results are also discussed. (author)

  5. Computed tomography dose assessment for a 160 mm wide, 320 detector row, cone beam CT scanner

    International Nuclear Information System (INIS)

    Geleijns, J; Bruin, P W de; Salvado Artells, M; Mather, R; Muramatsu, Y; McNitt-Gray, M F

    2009-01-01

    Computed tomography (CT) dosimetry should be adapted to the rapid developments in CT technology. Recently a 160 mm wide, 320 detector row, cone beam CT scanner that challenges the existing Computed Tomography Dose Index (CTDI) dosimetry paradigm was introduced. The purpose of this study was to assess dosimetric characteristics of this cone beam scanner, to study the appropriateness of existing CT dose metrics and to suggest a pragmatic approach for CT dosimetry for cone beam scanners. Dose measurements with a small Farmer-type ionization chamber and with 100 mm and 300 mm long pencil ionization chambers were performed free in air to characterize the cone beam. According to the most common dose metric in CT, namely CTDI, measurements were also performed in 150 mm and 350 mm long CT head and CT body dose phantoms with 100 mm and 300 mm long pencil ionization chambers, respectively. To explore effects that cannot be measured with ionization chambers, Monte Carlo (MC) simulations of the dose distribution in 150 mm, 350 mm and 700 mm long CT head and CT body phantoms were performed. To overcome inconsistencies in the definition of CTDI 100 for the 160 mm wide cone beam CT scanner, doses were also expressed as the average absorbed dose within the pencil chamber (D-bar 100 ). Measurements free in air revealed excellent correspondence between CTDI 300air and D-bar 100air , while CTDI 100air substantially underestimates CTDI 300air . Results of measurements in CT dose phantoms and corresponding MC simulations at centre and peripheral positions were weighted and revealed good agreement between CTDI 300w , D-bar 100w and CTDI 600w , while CTDI 100w substantially underestimates CTDI 300w . D-bar 100w provides a pragmatic metric for characterizing the dose of the 160 mm wide cone beam CT scanner. This quantity can be measured with the widely available 100 mm pencil ionization chamber within 150 mm long CT dose phantoms. CTDI 300w measured in 350 mm long CT dose phantoms serves

  6. Radiation condition in computerized tomography (CT): determination and calibration of dosemeters

    International Nuclear Information System (INIS)

    Adrade, L.C.; Peixoto, J.G.P.

    2016-01-01

    RQT is the standard for radiation conditions in computed tomography . It simulates a beam unrelieved of a CT scanner . The camera pencil ionization dosimeter is used in CT. The LNMRI become known characterization of RQT radiation conditions and the secondary standard calibration for type pencil ionisation chambers in its lab. The obtained beam has the characteristics required by IEC 61267. The results of the calibration presented combined uncertainty expanded to 95.45% from 2.22% . (author)

  7. A rigid motion correction method for helical computed tomography (CT)

    International Nuclear Information System (INIS)

    Kim, J-H; Kyme, A; Fulton, R; Nuyts, J; Kuncic, Z

    2015-01-01

    We propose a method to compensate for six degree-of-freedom rigid motion in helical CT of the head. The method is demonstrated in simulations and in helical scans performed on a 16-slice CT scanner. Scans of a Hoffman brain phantom were acquired while an optical motion tracking system recorded the motion of the bed and the phantom. Motion correction was performed by restoring projection consistency using data from the motion tracking system, and reconstructing with an iterative fully 3D algorithm. Motion correction accuracy was evaluated by comparing reconstructed images with a stationary reference scan. We also investigated the effects on accuracy of tracker sampling rate, measurement jitter, interpolation of tracker measurements, and the synchronization of motion data and CT projections. After optimization of these aspects, motion corrected images corresponded remarkably closely to images of the stationary phantom with correlation and similarity coefficients both above 0.9. We performed a simulation study using volunteer head motion and found similarly that our method is capable of compensating effectively for realistic human head movements. To the best of our knowledge, this is the first practical demonstration of generalized rigid motion correction in helical CT. Its clinical value, which we have yet to explore, may be significant. For example it could reduce the necessity for repeat scans and resource-intensive anesthetic and sedation procedures in patient groups prone to motion, such as young children. It is not only applicable to dedicated CT imaging, but also to hybrid PET/CT and SPECT/CT, where it could also ensure an accurate CT image for lesion localization and attenuation correction of the functional image data. (paper)

  8. A rigid motion correction method for helical computed tomography (CT)

    Science.gov (United States)

    Kim, J.-H.; Nuyts, J.; Kyme, A.; Kuncic, Z.; Fulton, R.

    2015-03-01

    We propose a method to compensate for six degree-of-freedom rigid motion in helical CT of the head. The method is demonstrated in simulations and in helical scans performed on a 16-slice CT scanner. Scans of a Hoffman brain phantom were acquired while an optical motion tracking system recorded the motion of the bed and the phantom. Motion correction was performed by restoring projection consistency using data from the motion tracking system, and reconstructing with an iterative fully 3D algorithm. Motion correction accuracy was evaluated by comparing reconstructed images with a stationary reference scan. We also investigated the effects on accuracy of tracker sampling rate, measurement jitter, interpolation of tracker measurements, and the synchronization of motion data and CT projections. After optimization of these aspects, motion corrected images corresponded remarkably closely to images of the stationary phantom with correlation and similarity coefficients both above 0.9. We performed a simulation study using volunteer head motion and found similarly that our method is capable of compensating effectively for realistic human head movements. To the best of our knowledge, this is the first practical demonstration of generalized rigid motion correction in helical CT. Its clinical value, which we have yet to explore, may be significant. For example it could reduce the necessity for repeat scans and resource-intensive anesthetic and sedation procedures in patient groups prone to motion, such as young children. It is not only applicable to dedicated CT imaging, but also to hybrid PET/CT and SPECT/CT, where it could also ensure an accurate CT image for lesion localization and attenuation correction of the functional image data.

  9. Computed tomography. CT and prognosis of hemophilus influenza meningitis

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, H.; Ogawa, K.; Shiihara, H.; Ohkubo, O.; Utsumi, Y. (Nihon Univ., Tokyo. School of Medicine)

    1981-06-01

    CT scanning was performed on 18 patients with hemophilus influenza meningitis. These findings were classified into 4 groups, i.e., focal cortical necrosis (F.C.N.), subdural effusion (S.Ef.), ventricular dilatation (V.D.), and subdural empyema (S.Em.). These findings reflect the process developing encephalopathy, and can be graded mild, moderate, and severe concerning the prognosis. Therefore, follow-up CT scanning is of value in elucidating the mechanism of encephalopathy and predicting the prognosis.

  10. Value of the dual phase 18F-FDG PET/CT with oral diuretic in the diagnosis of bladder cancer before therapy

    International Nuclear Information System (INIS)

    Li Hongsheng; Wu Hubing; Wang Qiaoyu; Han Yanjiang; Wang Quanshi

    2014-01-01

    Background: PET with 18 F-FDG has been considered of limited value for the detection of bladder cancer because of the urinary excretion of the tracer. Purpose: To investigate the clinical value of dual phase 18 F-FDG PET/CT with oral diuretic in the diagnosis of bladder cancer. Methods: 107 patients with suspected bladder cancer were enrolled in the present study from May, 2003 to May, 2012. Each patient underwent the whole body 18 F-FDG PET/CT scans routinely. After that, all patients received the forced diuresis by orally administration of furosemide (40 mg) and drinking a lot of water. Two hours later, after several times of urination, the patients underwent an additional delayed pelvic PET/CT scans. The intravesical radioactivity was compared between the routine and delayed the scans and the visualization of the tumor was evaluated. The diagnostic efficacy was determined based on the pathological examinations and the clinical following-up. Results: With the forced diuresis, intravesical 18 F-FDG activity decreased significantly in 96.3% of the patients. The lesions on the wall of urinary bladder were visualized clearly in the delayed PET images, which weren't seen in the rout/ne PET images. 18 F-FDG PET/CT was positive in 75 patients who all then received the operation. 69 patients were diagnosed pathologically to have the bladder cancer and 6 patients to have benign diseases. 18 F-FDG PET/CT was negative in another 32 patients. Four patients of them were then diagnosed to be bladder cancer. Another 28 patients were clinically followed up more than 6 months and none of them was found to have bladder cancer. The sensitivity, specificity and accuracy of the dual phase PET/CT imaging for diagnosing the bladder cancer were 94.5%(69/73), 82.4%(28/34) and 90.7%(97/107), respectively. Conclusion: The forced diuresis using oral furosemide can significantly reduce the intravesical radioactivity and improve the detectability of 18 F-FDG PET/CT for the bladder cancer

  11. The brain stem function in patients with brain bladder; Clinical evaluation using dynamic CT scan and auditory brainstem response

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Toshihiro (Yokohama City Univ. (Japan). Faculty of Medicine)

    1990-11-01

    A syndrome of detrusor-sphincter dyssynergia (DSD) is occasionally found in patients with brain bladder. To evaluate the brain stem function in cases of brain bladder, urodynamic study, dynamic CT scan of the brain stem (DCT) and auditory brainstem response (ABR) were performed. The region of interest of DCT aimed at the posterolateral portion of the pons. The results were analysed in contrast with the presense of DSD in urodynamic study. DCT studies were performed in 13 cases with various brain diseases and 5 control cases without neurological diseases. Abnormal patterns of the time-density curve consisted of low peak value, prolongation of filling time and low rapid washout ratio (low clearance ratio) of the contrast medium. Four of 6 cases with DSD showed at least one of the abnormal patterns of the time-density curve bilaterally. In 7 cases without DSD none showed bilateral abnormality of the curve and in 2 of 7 cases only unilateral abnormality was found. ABR was performed in 8 patients with brain diseases. The interpeak latency of the wave I-V (I-V IPL) was considered to be prolonged in 2 cases with DSD compared to that of 4 without DSD. In 2 cases with DSD who had normal DCT findings, measurement of the I-V IPL was impossible due to abnormal pattern of the ABR wave. Above mentioned results suggests the presence of functional disturbance at the posterolateral portion of the pons in cases of brain bladder with DSD. (author).

  12. Artifacts in conventional computed tomography (CT) and free breathing four-dimensional CT induce uncertainty in gross tumor volume determination

    DEFF Research Database (Denmark)

    Persson, Gitte Fredberg; Nygaard, Ditte Eklund; Af Rosenschöld, Per Munck

    2011-01-01

    PURPOSE: Artifacts impacting the imaged tumor volume can be seen in conventional three-dimensional CT (3DCT) scans for planning of lung cancer radiotherapy but can be reduced with the use of respiration-correlated imaging, i.e., 4DCT or breathhold CT (BHCT) scans. The aim of this study was to com......PURPOSE: Artifacts impacting the imaged tumor volume can be seen in conventional three-dimensional CT (3DCT) scans for planning of lung cancer radiotherapy but can be reduced with the use of respiration-correlated imaging, i.e., 4DCT or breathhold CT (BHCT) scans. The aim of this study...... was to compare delineated gross tumor volume (GTV) sizes in 3DCT, 4DCT, and BHCT scans of patients with lung tumors. METHODS AND MATERIALS: A total of 36 patients with 46 tumors referred for stereotactic radiotherapy of lung tumors were included. All patients underwent positron emission tomography (PET)/CT, 4DCT......, and BHCT scans. GTVs in all CT scans of individual patients were delineated during one session by a single physician to minimize systematic delineation uncertainty. The GTV size from the BHCT was considered the closest to true tumor volume and was chosen as the reference. The reference GTV size...

  13. Image characteristics of cone beam computed tomography using a CT performance phantom

    International Nuclear Information System (INIS)

    Han, Choong Wan; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan

    2007-01-01

    To evaluate the characteristics of (widely used) cone beam computed tomography (CBCT) images. Images were obtained with CT performance phantoms (The American Association of Physicists in Medicine; AAPM). CT phantom as the destination by using PSR 9000N TM dental CT system (Asahi Roentgen Ind. Co., Ltd., Japan) and i-CAT CBCT (Imaging Science International Inc., USA) that have different kinds of detectors and field of view, and compared these images with the CT number for linear attenuation, contrast resolution, and spatial resolution. CT number of both PSR 9000N TM dental CT system and i-CAT CBCT did not conform to the base value of CT performance phantom. The contrast of i-CAT CBCT is higher than that of PSR 9000N T M dental CT system. Both contrasts were increased according to thickness of cross section. Spatial resolution and shapes of reappearance was possible up to 0.6 mm in PSR 9000N T M dental CT system and up to 1.0 mm in i-CAT CBCT. Low contrast resolution in region of low contrast sensitivity revealed low level at PSR 9000N T M dental CT system and i-CAT CBCT. CBCT images revealed higher spatial resolution, however, contrast resolution in region of low contrast sensitivity was the inferiority of image characteristics

  14. Brain abscess in a Japanese Black calf: Utility of computed tomography (CT)

    International Nuclear Information System (INIS)

    El-Khodery, S.; Yamada, K.; Aoki, D.; Kamio, K.; Kishimoto, M.; Shimizu, J.; Kobayashi, Y.; Ishii, M.; Inokuma, H.; Yamauchi, S.; Matsui, T.

    2008-01-01

    Computed tomography (CT) was used for diagnosis of brain abscess in a 6-month-old, Japanese Black calf presented with neurological dysfunction, compulsive circling and vision disturbance. CT images showed asymmetric lateral ventricles, and presence of intra-cranial multiple low absorption lesions surrounded by capsule suggestive of abscess in the right cerebral hemisphere. Postmortem examination revealed marked swelling of right cerebral hemisphere and olfactory bulb. Multilocular large abscess containing creamy pus was found to occupy most area of periventricular and lateral ventricle. Fusobacterium necrophrum was isolated from the abscess contents as the causative agent. These results demonstrate that CT is useful tool for tentative diagnosis of bovine brain abscess

  15. Comparison of 18F fluoride PET/CT and 99mTc-MDP bone scan in the detection of skeletal metastases in urinary bladder carcinoma.

    Science.gov (United States)

    Chakraborty, Dhritiman; Bhattacharya, Anish; Mete, Uttam Kumar; Mittal, Bhagwant Rai

    2013-08-01

    The aim of this study was to compare (18)F-fluoride PET/CT and (99m)Tc-MDP bone scintigraphy in the detection of skeletal metastases in urinary bladder carcinoma. In this prospective study, 48 patients with urinary bladder carcinoma (44 male and 4 female patients, aged 35-80 years) underwent (99m)Tc-MDP planar and SPECT/CT bone scan (BS) followed by (18)F-fluoride PET/CT within 48 hours. Skeletal metastasis diagnosed on each of these techniques was compared against a final diagnosis based on contrast-enhanced CT, MRI, skeletal survey, clinical follow-up, and histological correlation. (18)F-fluoride PET/CT identified bony metastases and changed the management in 17 of 48 patients (35%). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of (99m)Tc-MDP planar BS were 82.35%, 64.51%, 56%, 86.95%, and 70.83%; of (99m)Tc-MDP SPECT/CT were 88.23%, 74.19%, 65.21%, 92%, and 79.16%; and of (18)F-fluoride PET/CT were 100%, 87.09%, 80.95%, 100%, and 91.66%, respectively. Fair agreement between (99m)Tc-MDP planar BS and F-fluoride PET/CT (κ = 0.42) and excellent agreement between SPECT/CT and (18)F-fluoride PET/CT (κ = 0.74) were found. ( 18)F-fluoride PET/CT has higher sensitivity, specificity, positive predictive value, negative predictive value, and accuracy in detecting bone metastases in urinary bladder carcinoma than conventional (99m)Tc-MDP planar BS. SPECT/CT improves all these parameters compared with planar BS and may serve as a cost-effective screening procedure for the detection of skeletal metastases in high-risk patients.

  16. A prospective study to assess the bladder distension effects on dosimetry in intracavitary brachytherapy of cervical cancer via computed tomography-assisted techniques

    International Nuclear Information System (INIS)

    Sun, L.-M.; Huang, H.-Y.; Huang, E.-Y.; Wang, C.-J.; Ko, S.-F.; Lin Hao; Song, J.-C.

    2005-01-01

    Background and purpose: Intracavitary brachytherapy (ICBT) is as important as external beam radiotherapy (EBRT) for the radical radiotherapy of uterine cervical cancer. The degree of urinary bladder distension during ICBT may affect the dose distribution in the bladder and rectum, to which an overdose may increase the chance of developing treatment-related complications. The purpose of this prospective study was to assess and quantify the impact of bladder distension on dosimetry in ICBT in patients with cervical cancer. Patients and methods: We recruited 20 patients with cervical cancer during a 12-month period. Inclusion criteria included pathological diagnosis of cervical cancer with IA to IIIB stages, and intact uterus. Patients were evaluated for brachytherapy after EBRT, and eligible individuals (cervical os could be identified clearly) were invited enter to this protocol to receive ICBT. In the first brachytherapy, bladder preparation (evacuation and distension by a Foley catheter) and CT scan were performed soon after the insertion of CT-compatible applicators. Then the bladder wall doses [median dose, maximum dose and dose-volume histograms (DVH)] were calculated via the PLATO computer planning system (Nucletron PLATO-RTS version 2.0). The individual data regarding doses and DVH were collected and compared. Bladder distension may shift the applicator position, and posterior displacement of the applicator system may increase the dose to the rectal wall, so this effect was also evaluated. Results: All the continuous variables of these 20 patients followed a normal distribution. By paired t-test and multiple linear regression analysis, we found that bladder distension statistically significantly decreased the median bladder wall dose with an average reduction of 48% of the dose of an empty bladder (P<0.001), and the maximum dose did not change; on the other hand, the bladder distension did not have any adverse effects on the rectal wall doses. Conclusions

  17. Indications for computed tomography (CT-) diagnostics in proximal humeral fractures

    DEFF Research Database (Denmark)

    Bahrs, Christian; Rolauffs, Bernd; Südkamp, Norbert P

    2009-01-01

    diagnostics depending on the fractured parts. METHODS: In a prospective diagnostic study in two level 1 trauma centers, 44 patients with proximal humeral fractures were diagnosed with conventional X-rays (22 AP + axillary views, 22 AP + scapular Y-views) and CT (multi-planar reconstruction (MPR) and maximum...... diagnostic methods was assessed according to the number of fractured parts (Bonferroni-Holm adjustment). RESULTS: There was significantly more overlap of the fractured region on the scapular Y-views (mean 71.5%, range 45-90%) than on axillary views (mean 56.2%, range 10.5-100%). CT-diagnostics allowed...

  18. Inflammatory pseudo tumor (pseudo sarcoma) of the urinary bladder: clinical aspects and computed tomography images

    International Nuclear Information System (INIS)

    Romero, A.; Bueno, A.; Trigo, J.E.; Torres, A.

    1998-01-01

    Inflammatory pseudo tumor (pseudosarcoma) of the urinary bladder is an uncommon lesion with benign histopathological features. It consists of large cell proliferation, spindle-cell morphology (myofibroblasts) deriving from the bladder sub mucosa. It can present in patients of either sex and of any age; on occasion, it has been related to a history of surgery or previous bladder injury. Both the clinical and radiological features are nonspecific in that they do not differentiate this lesion from malignant disease; its diagnosis can only be definitively established by histopathological study. We present a case of inflammatory bladder pseudo tumor in a young girl, describing the clinical and radiological features of this lesion, which only rarely has been dealt with in the literature, particularly that concerning radiology. (Author) 13 refs

  19. Progress in analysis of computed tomography (CT) images of hardwood logs for defect detection

    Science.gov (United States)

    Erol Sarigul; A. Lynn Abbott; Daniel L. Schmoldt

    2003-01-01

    This paper addresses the problem of automatically detecting internal defects in logs using computed tomography (CT) images. The overall purpose is to assist in breakdown optimization. Several studies have shown that the commercial value of resulting boards can be increased substantially if defect locations are known in advance, and if this information is used to make...

  20. SedCT: MATLAB™ tools for standardized and quantitative processing of sediment core computed tomography (CT) data collected using a medical CT scanner

    Science.gov (United States)

    Reilly, B. T.; Stoner, J. S.; Wiest, J.

    2017-08-01

    Computed tomography (CT) of sediment cores allows for high-resolution images, three-dimensional volumes, and down core profiles. These quantitative data are generated through the attenuation of X-rays, which are sensitive to sediment density and atomic number, and are stored in pixels as relative gray scale values or Hounsfield units (HU). We present a suite of MATLAB™ tools specifically designed for routine sediment core analysis as a means to standardize and better quantify the products of CT data collected on medical CT scanners. SedCT uses a graphical interface to process Digital Imaging and Communications in Medicine (DICOM) files, stitch overlapping scanned intervals, and create down core HU profiles in a manner robust to normal coring imperfections. Utilizing a random sampling technique, SedCT reduces data size and allows for quick processing on typical laptop computers. SedCTimage uses a graphical interface to create quality tiff files of CT slices that are scaled to a user-defined HU range, preserving the quantitative nature of CT images and easily allowing for comparison between sediment cores with different HU means and variance. These tools are presented along with examples from lacustrine and marine sediment cores to highlight the robustness and quantitative nature of this method.

  1. Urinary bladder cancer: role of MR imaging.

    Science.gov (United States)

    Verma, Sadhna; Rajesh, Arumugam; Prasad, Srinivasa R; Gaitonde, Krishnanath; Lall, Chandana G; Mouraviev, Vladimir; Aeron, Gunjan; Bracken, Robert B; Sandrasegaran, Kumaresan

    2012-01-01

    Urinary bladder cancer is a heterogeneous disease with a variety of pathologic features, cytogenetic characteristics, and natural histories. It is the fourth most common cancer in males and the tenth most common cancer in females. Urinary bladder cancer has a high recurrence rate, necessitating long-term surveillance after initial therapy. Early detection is important, since up to 47% of bladder cancer-related deaths may have been avoided. Conventional computed tomography (CT) and magnetic resonance (MR) imaging are only moderately accurate in the diagnosis and local staging of bladder cancer, with cystoscopy and pathologic staging remaining the standards of reference. However, the role of newer MR imaging sequences (eg, diffusion-weighted imaging) in the diagnosis and local staging of bladder cancer is still evolving. Substantial advances in MR imaging technology have made multiparametric MR imaging a feasible and reasonably accurate technique for the local staging of bladder cancer to optimize treatment. In addition, whole-body CT is the primary imaging technique for the detection of metastases in bladder cancer patients, especially those with disease that invades muscle. © RSNA, 2012.

  2. A water-soluble triiodo amino acid and its dendrimer conjugate for computerized tomography (CT imaging

    Directory of Open Access Journals (Sweden)

    MARTIN W. BRECHBIEL

    2005-02-01

    Full Text Available Prolonging the circulation of an imaging agent is vital for making it suitable for blood pool (vascular imaging. Medical applications of vascular imaging include cardiovascular disease, abnormal capillary permeability, and tumor neovascularity. As low molecular weight computerized tomography (CT enhancement agents are characterized by inconveniently fast clearance, macromolecular compounds (both natural and synthetic have gained a wide recongnition for possessing better characteristics for performing blood imaging tasks. Herein, the syntheses and characterization of a new water-soluble triiodo amino acid, 3-[(N,N-dimethylaminoacetyl amino]-a-ethyl-2,4,6-triiodobenzenepropanoic acid (DMAA-IPA and its Starburst PAMAMgeneration 4.0 dendrimer conjugate, G-4-(DMAA-IPA37 are described. The applicability of G-4-(DMAA-IPA37 as a potential macromolecular angiographic CT contrast agent is discussed. The linear relationship between organically bound iodine concentration and CT Hounsfield units has been established thus allowing for quantification uses of CT imaging as well.

  3. Metastatic meningioma: positron emission tomography CT imaging findings.

    LENUS (Irish Health Repository)

    Brennan, C

    2010-12-01

    The imaging findings of a case of metastasing meningioma are described. The case illustrates a number of rare and interesting features. The patient presented with haemoptysis 22 years after the initial resection of an intracranial meningioma. CT demonstrated heterogeneous masses with avid peripheral enhancement without central enhancement. Blood supply to the larger lesion was partially from small feeding vessels from the inferior pulmonary vein. These findings correlate with a previously published case in which there was avid uptake of fluoro-18-deoxyglucose peripherally with lesser uptake centrally. The diagnosis of metastasing meningioma was confirmed on percutaneous lung tissue biopsy.

  4. Bladder cancer diagnosis with fluorescence-image-guided optical coherence tomography

    Science.gov (United States)

    Wang, Z. G.; Durand, D. B.; Adler, H.; Pan, Y. T.

    2006-02-01

    A fluorescence-image-guided OCT (FIG-OCT) system is described, and its ability to enhance the sensitivity and specificity is examined in an animal bladder cancer model. Total 97 specimens were examined by fluorescence imaging, OCT and histological microscopy. The sensitivity and specificity of FIG-OCT is 100% and 93% respectively, compared to 79% and 53% for fluorescence imaging, while the OCT examination time has been dramatically decreased by 3~4 times. In combination of endoscopic OCT, FIG-OCT is a promising technique for effective early bladder cancer diagnosis.

  5. Comparison of positron emission tomography/CT and bremsstrahlung imaging following Y-90 radiation synovectomy

    International Nuclear Information System (INIS)

    Barber, Thomas W.; Yap, Kenneth S.K.; Cherk, Martin H.; Kalff, Victor; Powell, Anne

    2013-01-01

    The aim of this study is to compare the results of positron emission tomography (PET)/CT with bremsstrahlung imaging following Y-90 radiation synovectomy. All patients referred to our institution for Y-90 radiation synovectomy between July 2011 and February 2012 underwent both PET/CT and bremsstrahlung planar (±single photon emission computed tomography (SPECT) or SPECT/CT) imaging at 4 or 24 h following administration of Y-90 silicate colloid. PET image acquisition was performed for between 15 and 20min. In patients who underwent SPECT, side-by-side comparison with PET was performed and image quality/resolution scored using a five-point scale. The distribution pattern of Y-90 on PET and bremsstrahlung imaging was compared with the intra- or extra-articular location of Y-90 activity on fused PET/CT. Thirteen joints (11 knees and two ankles) were imaged with both PET/CT and planar bremsstrahlung imaging with 12 joints also imaged with bremsstrahlung SPECT. Of the 12 joints imaged with SPECT, PET image quality/resolution was superior in 11 and inferior in one. PET demonstrated a concordant distribution pattern compared with bremsstrahlung imaging in all scans, with the pattern classified as diffuse in 12 and predominantly focal in one. In all 12 diffuse scans, PET/CT confirmed the Y-90 activity to be located intra-articularly. In the one predominantly focal scan, the fused PET/CT images localised the Y-90 activity to mostly lie in the extra-articular space of the knee. PET/CT can provide superior image quality compared with bremsstrahlung imaging and may enable reliable detection of extra-articular Y-90 activity when there are focal patterns on planar bremsstrahlung imaging.

  6. [Digital volume tomography : Dedicated scanner and cone beam CT with C‑arm systems].

    Science.gov (United States)

    Fiebich, M; Weber, D

    2018-03-01

    Digital volume tomography (DVT) and cone-beam computed tomography (CT) with C‑arm systems have become established three-dimensional imaging systems as an alternative to CT in some application areas. The technology of the systems is well developed so that they have become a competing method to CT imaging in terms of image quality and radiation exposure. An advantage is the better spatial resolution, preferably with dedicated scanner systems, especially in the z direction. The radiation exposure of CT, cone beam CT and DVT are comparable, if the exposure parameter in CT imaging can be adjusted to the lower exposure levels. Advantages of these systems are that they can be used for imaging in a better workflow or to acquire images under conditions not possible in CT, e. g. imaging under stress in orthopedics or to take images in the corona technique with a horizontal gantry in cone-beam CT mammography PRACTICAL RECOMMENDATIONS: The use of three-dimensional imaging is becoming more frequent and will replace planar radiography in additional clinical situations. The three-dimensional imaging without superpositioning of structures has advantages in the visibility of structures and the spatial relation to other organs and structures. In guidelines and recommendations, the number of recommendations given for the use of three-dimensional imaging is increasing. This leads to a small increase in the radiation exposure of patients, a trend which is reflected in the annual reports of the Federal Office for Radiation Protection.

  7. The CT Scanner Facility at Stellenbosch University: An open access X-ray computed tomography laboratory

    Science.gov (United States)

    du Plessis, Anton; le Roux, Stephan Gerhard; Guelpa, Anina

    2016-10-01

    The Stellenbosch University CT Scanner Facility is an open access laboratory providing non-destructive X-ray computed tomography (CT) and a high performance image analysis services as part of the Central Analytical Facilities (CAF) of the university. Based in Stellenbosch, South Africa, this facility offers open access to the general user community, including local researchers, companies and also remote users (both local and international, via sample shipment and data transfer). The laboratory hosts two CT instruments, i.e. a micro-CT system, as well as a nano-CT system. A workstation-based Image Analysis Centre is equipped with numerous computers with data analysis software packages, which are to the disposal of the facility users, along with expert supervision, if required. All research disciplines are accommodated at the X-ray CT laboratory, provided that non-destructive analysis will be beneficial. During its first four years, the facility has accommodated more than 400 unique users (33 in 2012; 86 in 2013; 154 in 2014; 140 in 2015; 75 in first half of 2016), with diverse industrial and research applications using X-ray CT as means. This paper summarises the existence of the laboratory's first four years by way of selected examples, both from published and unpublished projects. In the process a detailed description of the capabilities and facilities available to users is presented.

  8. Computed tomography from photon statistics to modern cone-beam CT

    CERN Document Server

    Buzug, T M

    2008-01-01

    Tis book provides an overview of X-ray technology, the historic developmental milestones of modern CT systems, and gives a comprehensive insight into the main reconstruction methods used in computed tomography. Te basis of reconstr- tion is, undoubtedly, mathematics. However, the beauty of computed tomography cannot be understood without a detailed knowledge of X-ray generation, photon- matter interaction, X-ray detection, photon statistics, as well as fundamental signal processing concepts and dedicated measurement systems. Terefore, the reader will ?nd a number of references to these basic d

  9. Intraprocedural yttrium-90 positron emission tomography/CT for treatment optimization of yttrium-90 radioembolization.

    Science.gov (United States)

    Bourgeois, Austin C; Chang, Ted T; Bradley, Yong C; Acuff, Shelley N; Pasciak, Alexander S

    2014-02-01

    Radioembolization with yttrium-90 ((90)Y) microspheres relies on delivery of appropriate treatment activity to ensure patient safety and optimize treatment efficacy. We report a case in which (90)Y positron emission tomography (PET)/computed tomography (CT) was performed to optimize treatment planning during a same-day, three-part treatment session. This treatment consisted of (i) an initial (90)Y infusion with a dosage determined using an empiric treatment planning model, (ii) quantitative (90)Y PET/CT imaging, and (iii) a secondary infusion with treatment planning based on quantitative imaging data with the goal of delivering a specific total tumor absorbed dose. © 2014 SIR Published by SIR All rights reserved.

  10. The assessment of tumor blood flow factors using dynamic CT; Comparison with positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Miyakawa, Emiko (Chiba Univ. (Japan). School of Medicine)

    1993-03-01

    The dynamic computed tomography (CT) was performed by using rapid-sequence scanning following an intravenous bolus injection of contrast material. Time-density curve was applied for gamma variate curve fitting and CT attenuation values were applied for two compartment model. The value of 1/CM, k[sub 1] and k[sub 2] were defined as the blood flow factors in this study. The inhalation of C[sup 15]O[sub 2] using positron emission tomography (PET) can be useful for determining regional tumor blood flow (rBF). CT and PET were performed in 12 patients. The diagnosis was malignant lymphoma in four, and others; two liver metastases, one focal nodular hyperplasia of the liver, one dermatofibrosarcoma, one hepatocellular carcinoma, one malignant melanoma, one malignant meningioma, one bone metastasis. The correlations among rBF, 1/CM, and k[sub 1] were good, and better correlations were obtained among tumor blood flow factors and rBF in the case of the tumors which existed far from air way and/or had low blood flow. The distance from air way effected both the value of rBF and tumor blood flow factors. Both the distance from air way and pathology caused conflicting results between rBF and tumor blood flow factors. Dynamic CT was particularly useful for evaluating the blood flow of tumors that had contact with air way. (author).

  11. Chest tube placement in thorax trauma - comparison chest X-ray and computed tomography (CT)

    International Nuclear Information System (INIS)

    Heim, P.; Maas, R.; Buecheler, E.; Tesch, C.

    1998-01-01

    Estimation of chest tube placement in patients with thoracic trauma with regard to chest tube malposition in chest radiography in the supine position compared to additional computed tomography of the thorax. Material and methods: Apart from compulsory chest radiography after one or multiple chest tube insertions, 31 severely injured patients with thoracic trauma underwent a CT scan of the thorax. These 31 patients with 40 chest tubes constituted the basis for the present analysis. Results: In chest radiography in the supine position there were no chest tube malpositions (n=40); In the CT scans 25 correct positions, 7 pseudo-malpositions, 6 intrafissural and 2 intrapulmonary malpositions were identified. Moreover 16 sufficient, 18 insufficient and 6 indifferent functions of the chest tubes were seen. Conclusion: In case of lasting clinical problems and questionable function of the chest tube, chest radiography should be supplemented by a CT scan of the thorax in order to estimate the position of the chest tube. (orig.) [de

  12. Thoracic CT in the ED: a study of thoracic computed tomography utilisation.

    LENUS (Irish Health Repository)

    Williams, E

    2010-02-01

    The aim of this retrospective study was to investigate the use of thoracic Computed Tomography (CT) in the Emergency Department of a Dublin Academic Teaching Hospital over a six month period. Data was retrieved using the hospital\\'s computerised information system. There were 202 referrals in total for thoracic CT from the Emergency Department during this time period. The most common indication for thoracic CT referral was for the investigation of pulmonary embolism with 127 (63%) referrals. There were 40 (25%) referrals for suspected malignancy and lung disease, whilst 8 (4%) of the referrals were for investigation of thoracic aortic dissection, 8 (4%) for infection, and 6 (3%) were for investigation of thoracic injury. Only 8 (4%) of all referrals were for investigation of injury as a result of chest trauma.

  13. Early dynamic imaging in {sup 68}Ga- PSMA-11 PET/CT allows discrimination of urinary bladder activity and prostate cancer lesions

    Energy Technology Data Exchange (ETDEWEB)

    Uprimny, Christian; Kroiss, Alexander Stephan; Decristoforo, Clemens; Warwitz, Boris; Scarpa, Lorenza; Roig, Llanos Geraldo; Kendler, Dorota; Guggenberg, Elisabeth von; Virgolini, Irene Johanna [Medical University Innsbruck, Department of Nuclear Medicine, Innsbruck (Austria); Fritz, Josef [Medical University Innsbruck, Department for Medical Statistics, Informatics and Health Economics, Innsbruck (Austria); Bektic, Jasmin; Horninger, Wolfgang [Medical University Innsbruck, Department of Urology, Innsbruck (Austria)

    2017-05-15

    PET/CT with {sup 68}Ga-labelled prostate-specific membrane antigen (PSMA)-ligands has been proven to establish a promising imaging modality in the work-up of prostate cancer (PC) patients with biochemical relapse. Despite a high overall detection rate, the visualisation of local recurrence may be hampered by high physiologic tracer accumulation in the urinary bladder on whole body imaging, usually starting 60 min after injection. This study sought to verify whether early dynamic {sup 68}Ga-PSMA-11 (HBED-CC)PET/CT can differentiate pathologic PC-related tracer uptake from physiologic tracer accumulation in the urinary bladder. Eighty consecutive PC patients referred to {sup 68}Ga -PSMA-11 PET/CT were included in this retrospective analysis (biochemical relapse: n = 64; primary staging: n = 8; evaluation of therapy response/restaging: n = 8). In addition to whole-body PET/CT acquisition 60 min post injection early dynamic imaging of the pelvis in the first 8 min after tracer injection was performed. SUV{sub max} of pathologic lesions was calculated and time-activity curves were generated and compared to those of urinary bladder and areas of physiologic tracer uptake. A total of 55 lesions consistent with malignancy on 60 min whole body imaging exhibited also pathologic {sup 68}Ga-PSMA-11 uptake during early dynamic imaging (prostatic bed/prostate gland: n = 27; lymph nodes: n = 12; bone: n = 16). All pathologic lesions showed tracer uptake within the first 3 min, whereas urinary bladder activity was absent within the first 3 min of dynamic imaging in all patients. Suv{sub max} was significantly higher in PC lesions in the first 6 min compared to urinary bladder accumulation (p < 0.001). In the subgroup of PC patients with biochemical relapse the detection rate of local recurrence could be increased from 20.3 to 29.7%. Early dynamic imaging in {sup 68}Ga-PSMA-11 PET/CT reliably enables the differentiation of pathologic tracer uptake in PC lesions from physiologic

  14. Predictive value of pattern classification 24 hours after radiofrequency ablation of liver metastases on CT and positron emission tomography/CT.

    Science.gov (United States)

    Vandenbroucke, Frederik; Vandemeulebroucke, Jef; Ilsen, Bart; Verdries, Douwe; Belsack, Dries; Everaert, Hendrik; Buls, Nico; Ros, Pablo R; de Mey, Johan

    2014-08-01

    To assess a classification scheme for predicting local tumor progression (LTP) after radiofrequency (RF) ablation of liver metastases, using predefined patterns on contrast-enhanced computed tomography (CT) and positron emission tomography (PET) combined with CT (PET/CT) acquired 24 hours after RF ablation. There were 45 metastases in 20 patients treated. After 24 hours, imaging of the ablation zones was performed with contrast-enhanced PET/CT. Three independent radiologists prospectively assessed contrast-enhanced CT and combined PET/CT images to identify three patterns: pattern I, no tissue enhancement or fluorodeoxyglucose uptake between the ablation zone and the liver parenchyma; pattern II, a rimlike pattern; and pattern III, a peripheral nodule. PET/CT images obtained after 8-10 weeks were evaluated for LTP. The patterns were analyzed for their sensitivity, specificity, positive predictive value, and negative predictive value for predicting LTP. Pattern I was most frequently observed (81% for contrast-enhanced CT and 61% for PET/CT) as well as for ablation zones that showed LTP (52% and 37%, respectively). Conversely, pattern II was observed for tumors that were completely ablated (6% and 29%, respectively). Patterns II and III together had the highest sensitivity for predicting LTP (48% and 63%, respectively); pattern III had the highest specificity (94% and 95%, respectively). For nodular patterns, test characteristics were better for PET/CT compared with contrast-enhanced CT, but the difference was not significant. Nodular patterns > 1 cm achieved high positive predictive value (both 100%). Inflammation and hyperemia can hinder interpretation on imaging 24 hours after RF ablation, especially on PET/CT. Nodular patterns around the ablation zone on early contrast-enhanced CT and PET/CT have a high predictive value for LTP and should be taken into account for disease management. Copyright © 2014 SIR. Published by Elsevier Inc. All rights reserved.

  15. Reliability of the NINDS common data elements cranial tomography (CT) rating variables for traumatic brain injury (TBI)

    NARCIS (Netherlands)

    Harburg, Leah; McCormack, Erin; Kenney, Kimbra; Moore, Carol; Yang, Kelly; Vos, Pieter; Jacobs, Bram; Madden, Christopher J; Diaz-Arrastia, Ramon R; Bogoslovsky, Tanya

    2017-01-01

    Background: Non-contrast head computer tomography (CT) is widely used to evaluate eligibility of patients after acute traumatic brain injury (TBI) for clinical trials. The NINDS Common Data Elements (CDEs) TBI were developed to standardize collection of CT variables. The objectives of this study

  16. Ambient radiation levels in positron emission tomography/computed tomography (PET/CT) imaging center

    Energy Technology Data Exchange (ETDEWEB)

    Santana, Priscila do Carmo; Oliveira, Paulo Marcio Campos de; Mamede, Marcelo; Silveira, Mariana de Castro; Aguiar, Polyanna; Real, Raphaela Vila, E-mail: pridili@gmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil); Silva, Teogenes Augusto da [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2015-01-15

    Objective: to evaluate the level of ambient radiation in a PET/CT center. Materials and methods: previously selected and calibrated TLD-100H thermoluminescent dosimeters were utilized to measure room radiation levels. During 32 days, the detectors were placed in several strategically selected points inside the PET/CT center and in adjacent buildings. After the exposure period the dosimeters were collected and processed to determine the radiation level. Results: in none of the points selected for measurements the values exceeded the radiation dose threshold for controlled area (5 mSv/ year) or free area (0.5 mSv/year) as recommended by the Brazilian regulations. Conclusion: in the present study the authors demonstrated that the whole shielding system is appropriate and, consequently, the workers are exposed to doses below the threshold established by Brazilian standards, provided the radiation protection standards are followed. (author)

  17. Ambient radiation levels in positron emission tomography/computed tomography (PET/CT) imaging center

    Science.gov (United States)

    Santana, Priscila do Carmo; de Oliveira, Paulo Marcio Campos; Mamede, Marcelo; Silveira, Mariana de Castro; Aguiar, Polyanna; Real, Raphaela Vila; da Silva, Teógenes Augusto

    2015-01-01

    Objective To evaluate the level of ambient radiation in a PET/CT center. Materials and Methods Previously selected and calibrated TLD-100H thermoluminescent dosimeters were utilized to measure room radiation levels. During 32 days, the detectors were placed in several strategically selected points inside the PET/CT center and in adjacent buildings. After the exposure period the dosimeters were collected and processed to determine the radiation level. Results In none of the points selected for measurements the values exceeded the radiation dose threshold for controlled area (5 mSv/year) or free area (0.5 mSv/year) as recommended by the Brazilian regulations. Conclusion In the present study the authors demonstrated that the whole shielding system is appropriate and, consequently, the workers are exposed to doses below the threshold established by Brazilian standards, provided the radiation protection standards are followed. PMID:25798004

  18. CT in the diagnosis of enterovesical fistulae

    International Nuclear Information System (INIS)

    Goldman, S.M.; Fishman, E.K.; Gatewood, O.M.B.; Jones, B.; Siegelman, S.S.

    1985-01-01

    Enterovesical fistulae are difficult to demonstrate by conventional radiographic methods. Computed tomography (CT), a sensitive, noninvasive method of documenting the presence of such fistulae, is unique in its ability to outline the extravesical component of the primary disease process. Twenty enterovesical fistulae identified by CT were caused by diverticulitis (nine), carcinoma of the rectosigmoid (two), Crohn disease (three), gynecologic tumors (two), bladder cancer (one), cecal carcinoma (one), prostatic neoplasia (one), and appendiceal abscess (one). The CT findings included intravesical air (90%), passage of orally or rectally administered contrast medium into the bladder (20%), focal bladder-wall thickening (90%), thickening of adjacent bowel wall (85%), and an extraluminal mass that often contained air (75%). CT proved to be an important new method in the diagnosis of enterovesical fistulae

  19. CT in the diagnosis of enterovesical fistulae

    Energy Technology Data Exchange (ETDEWEB)

    Goldman, S.M.; Fishman, E.K.; Gatewood, O.M.B.; Jones, B.; Siegelman, S.S.

    1985-06-01

    Enterovesical fistulae are difficult to demonstrate by conventional radiographic methods. Computed tomography (CT), a sensitive, noninvasive method of documenting the presence of such fistulae, is unique in its ability to outline the extravesical component of the primary disease process. Twenty enterovesical fistulae identified by CT were caused by diverticulitis (nine), carcinoma of the rectosigmoid (two), Crohn disease (three), gynecologic tumors (two), bladder cancer (one), cecal carcinoma (one), prostatic neoplasia (one), and appendiceal abscess (one). The CT findings included intravesical air (90%), passage of orally or rectally administered contrast medium into the bladder (20%), focal bladder-wall thickening (90%), thickening of adjacent bowel wall (85%), and an extraluminal mass that often contained air (75%). CT proved to be an important new method in the diagnosis of enterovesical fistulae.

  20. How to interpret an unenhanced CT Brain scan. Part 1: Basic principles of Computed Tomography and relevant neuroanatomy

    Directory of Open Access Journals (Sweden)

    Thomas Osborne

    2016-08-01

    Full Text Available The aim of this article is to: Cover the basics of Computed Tomography (CT Brain imaging. Review relevant CT neuroanatomy. A CT image is produced by firing x-rays at a moving object which is then detected by an array of rotating detectors (Figure 1. The detected x-rays are then converted into a computerised signal which is used to produce a series of cross sectional images.

  1. Increased bladder wall thickness is associated with severe symptoms and reduced bladder capacity in patients with bladder pain syndrome

    Directory of Open Access Journals (Sweden)

    Shu-Yu Wu

    2016-12-01

    Conclusion: There are obvious differences in bladder CT scans of patients with symptoms of bladder pain due to different etiology. Increased BWT was associated with increased pain scores and decreased bladder capacity in patients with KC and IC. BWT on a CT scan might be considered a marker for the severity of bladder inflammation.

  2. Early dynamic imaging in 68Ga- PSMA-11 PET/CT allows discrimination of urinary bladder activity and prostate cancer lesions.

    Science.gov (United States)

    Uprimny, Christian; Kroiss, Alexander Stephan; Decristoforo, Clemens; Fritz, Josef; Warwitz, Boris; Scarpa, Lorenza; Roig, Llanos Geraldo; Kendler, Dorota; von Guggenberg, Elisabeth; Bektic, Jasmin; Horninger, Wolfgang; Virgolini, Irene Johanna

    2017-05-01

    PET/CT with 68 Ga-labelled prostate-specific membrane antigen (PSMA)-ligands has been proven to establish a promising imaging modality in the work-up of prostate cancer (PC) patients with biochemical relapse. Despite a high overall detection rate, the visualisation of local recurrence may be hampered by high physiologic tracer accumulation in the urinary bladder on whole body imaging, usually starting 60 min after injection. This study sought to verify whether early dynamic 68 Ga-PSMA-11 (HBED-CC)PET/CT can differentiate pathologic PC-related tracer uptake from physiologic tracer accumulation in the urinary bladder. Eighty consecutive PC patients referred to 68 Ga -PSMA-11 PET/CT were included in this retrospective analysis (biochemical relapse: n = 64; primary staging: n = 8; evaluation of therapy response/restaging: n = 8). In addition to whole-body PET/CT acquisition 60 min post injection early dynamic imaging of the pelvis in the first 8 min after tracer injection was performed. SUV max of pathologic lesions was calculated and time-activity curves were generated and compared to those of urinary bladder and areas of physiologic tracer uptake. A total of 55 lesions consistent with malignancy on 60 min whole body imaging exhibited also pathologic 68 Ga-PSMA-11 uptake during early dynamic imaging (prostatic bed/prostate gland: n = 27; lymph nodes: n = 12; bone: n = 16). All pathologic lesions showed tracer uptake within the first 3 min, whereas urinary bladder activity was absent within the first 3 min of dynamic imaging in all patients. Suv max was significantly higher in PC lesions in the first 6 min compared to urinary bladder accumulation (p bladder accumulation. Performance of early dynamic imaging in addition to whole body imaging 60 min after tracer injection might improve the detection rate of local recurrence in PC patients with biochemical relapse referred for 68 Ga-PSMA-11 PET/CT.

  3. Chest computed tomography-based scoring of thoracic sarcoidosis: Inter-rater reliability of CT abnormalities

    International Nuclear Information System (INIS)

    Heuvel, D.A.V. den; Es, H.W. van; Heesewijk, J.P. van; Spee, M.; Jong, P.A. de; Zanen, P.; Grutters, J.C.

    2015-01-01

    To determine inter-rater reliability of sarcoidosis-related computed tomography (CT) findings that can be used for scoring of thoracic sarcoidosis. CT images of 51 patients with sarcoidosis were scored by five chest radiologists for various abnormal CT findings (22 in total) encountered in thoracic sarcoidosis. Using intra-class correlation coefficient (ICC) analysis, inter-rater reliability was analysed and reported according to the Guidelines for Reporting Reliability and Agreement Studies (GRRAS) criteria. A pre-specified sub-analysis was performed to investigate the effect of training. Scoring was trained in a distinct set of 15 scans in which all abnormal CT findings were represented. Median age of the 51 patients (36 men, 70 %) was 43 years (range 26 - 64 years). All radiographic stages were present in this group. ICC ranged from 0.91 for honeycombing to 0.11 for nodular margin (sharp versus ill-defined). The ICC was above 0.60 in 13 of the 22 abnormal findings. Sub-analysis for the best-trained observers demonstrated an ICC improvement for all abnormal findings and values above 0.60 for 16 of the 22 abnormalities. In our cohort, reliability between raters was acceptable for 16 thoracic sarcoidosis-related abnormal CT findings. (orig.)

  4. Imaging of urinary bladder tumors

    International Nuclear Information System (INIS)

    Hadjidekov, G.

    2015-01-01

    Full text: Primary bladder neoplasms account for 2%-6% of all tumors, with urinary bladder cancer ranked as the fourth most common cancer in males. Transitional cell carcinoma (TCC) is the most common subtype of urothelial tumour accounting for approximately 90% of all urothelial cancers. It is typically observed in men aged 50-70 years with history of smoking or occupational exposure to carcinogens. Most urothelial neoplasms are low-grade papillary tumors, with high incidence of recurrence, requires rigorous follow-up but have a relatively good prognosis. Other bladder neoplasm include squamous cell carcinoma accounts for 2%-15% mainly according to geographic location; adenocarcinoma - less than 2% /both occurring in the context of chronic bladder infection and irritation/; mesenchymal tumors in 5%, with the most common examples being rhabdomyosarcoma in children and leiomyosarcoma in adults. More rare mesenchymal tumors include paraganglioma, lymphoma, leiomyoma and solitary fibrous tumor which have no specific typical imaging findings to be differentiated. Multidetector computed tomography urography is an efficient tool for diagnosis and follow-up in patients with transitional cell carcinoma and it can be considered the primary radiologic method for detection, staging and assessment of the entire urothelium regarding the multicentric nature of TCC. MRI is rapidly expanding modality of choice especially in locally staging the tumor and in controversies. Accurate TNM staging is primordial in choosing treatment and prognosis for patients with bladder carcinoma. Correct interpretation and classification of the tumour is helpful for the urologists to determine further management in these cases. The learning objectives of the presentation are: to illustrate the spectrum of CT and MRI findings and to assess their clinical value in patients with transitional cell carcinoma and some other bladder neoplasm; to discuss the TNM staging based on the imaging findings; to be

  5. Head CT scan

    Science.gov (United States)

    ... CT; Cranial CT; CT scan - skull; CT scan - head; CT scan - orbits; CT scan - sinuses; Computed tomography - ... Head CT is done in the hospital or radiology center. You lie on a narrow table that ...

  6. Computed tomography guidance. Fluoroscopy and more; CT-Steuerung. Fluoroskopie und mehr

    Energy Technology Data Exchange (ETDEWEB)

    Paprottka, P.M.; Reiser, M.F.; Trumm, C.G. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Angiographie und Interventionelle Radiologie, Institut fuer Klinische Radiologie, Muenchen (Germany); Helmberger, T. [Staedt. Klinikum Muenchen, Klinikum Bogenhausen, Institut fuer Diagnostische und Interventionelle Radiologie, Neuroradiologie und Nuklearmedizin, Muenchen (Germany)

    2013-11-15

    Although ultrasound and magnetic resonance imaging are competitive imaging modalities for the guidance of needle-based interventions, computed tomography (CT) is the only modality suitable for image-guided interventions in all regions of the body, including the lungs and bone. The ongoing technical development of CT involves accelerated image acquisition, significantly improved spatial resolution, CT scanners with an extended gantry diameter, acceleration of the procedure through joystick control of relevant functions of interventional CT by the interventional radiologist and tube current modulation to protect the hands of the examiner and radiosensitive organs of the patient. CT fluoroscopy can be used as a real-time method (the intervention is monitored under continuous CT fluoroscopy) or as a quick check method (repeated acquisitions of individual CT fluoroscopic images after each change of needle or table position). For the two approaches, multislice CT fluoroscopy (MSCTF) technique with wide detectors is particularly useful because even in the case of needle deviation from the center slice the needle tip is simultaneously visualised in the neighboring slices. With the aid of this technique a precise placement of interventional devices is possible even in angled access routes and in the presence of pronounced respiratory organ movements. As the reduction of CT fluoroscopy time significantly reduces radiation exposure for the patient and staff, the combination of a quick check technique and a low milliampere technique with multislice CT fluoroscopy devices is advantageous. (orig.) [German] Obwohl sonographisch und magnetresonanztomographisch gesteuerte Interventionen ernstzunehmende Konkurrenzverfahren sind, kann die Computertomographie als einzige bildgebende Modalitaet zur Steuerung von Interventionen in allen Koerperregionen (einschliesslich Lunge und Knochen) eingesetzt werden. Die technischen Weiterentwicklungen der Computertomographie beinhalten eine

  7. Computed tomography automatic exposure control techniques in 18F-FDG oncology PET-CT scanning.

    Science.gov (United States)

    Iball, Gareth R; Tout, Deborah

    2014-04-01

    Computed tomography (CT) automatic exposure control (AEC) systems are now used in all modern PET-CT scanners. A collaborative study was undertaken to compare AEC techniques of the three major PET-CT manufacturers for fluorine-18 fluorodeoxyglucose half-body oncology imaging. An audit of 70 patients was performed for half-body CT scans taken on a GE Discovery 690, Philips Gemini TF and Siemens Biograph mCT (all 64-slice CT). Patient demographic and dose information was recorded and image noise was calculated as the SD of Hounsfield units in the liver. A direct comparison of the AEC systems was made by scanning a Rando phantom on all three systems for a range of AEC settings. The variation in dose and image quality with patient weight was significantly different for all three systems, with the GE system showing the largest variation in dose with weight and Philips the least. Image noise varied with patient weight in Philips and Siemens systems but was constant for all weights in GE. The z-axis mA profiles from the Rando phantom demonstrate that these differences are caused by the nature of the tube current modulation techniques applied. The mA profiles varied considerably according to the AEC settings used. CT AEC techniques from the three manufacturers yield significantly different tube current modulation patterns and hence deliver different doses and levels of image quality across a range of patient weights. Users should be aware of how their system works and of steps that could be taken to optimize imaging protocols.

  8. c.29C>T polymorphism in the transforming growth factor-β1 (TGFB1) gene correlates with increased risk of urinary bladder cancer.

    Science.gov (United States)

    Gautam, Kirti Amresh; Pooja, Singh; Sankhwar, Satya Narayan; Sankhwar, Pushp Lata; Goel, Apul; Rajender, Singh

    2015-10-01

    TGF-β1 is a pleiotropic cytokine, which plays a dual role in tumor development. In the early stages, it inhibits the growth of tumor while in the late stages of carcinoma, it promotes tumor growth. The purpose of this study was to analyze the distribution of the TGFB1 gene polymorphisms between cases and controls so as to assess their correlation with bladder cancer risk. This study included 237 cases of urinary bladder cancer and 290 age matched controls from the same ethnic background. Three polymorphisms in the TGFB1 gene, c.29C>T (rs-1800470), c.74G>C (rs-1800471) and +140A>G (rs-13447341), were analyzed by direct DNA sequencing. Statistical analyses revealed no significant differences in the demographical data, except that the frequencies of smokers and non-vegetarians were higher in the cases. Eighty percent of the bladder cancer patients had superficial transitional cell carcinoma, and 53.16% and 26.31% of the patients were in grade I and grade II, respectively. We found that c.29C>T substitution increased the risk of bladder cancer significantly and recessive model of analysis was the best fitted model (p=0.004; OR=1.72 95% CI 1.18-2.50). A significantly higher risk in the recessive form was also suggested by co-dominant analysis showing that the homozygous form (TT) was a significant risk factor in comparison to CC and CT genotypes. The other two polymorphisms, c.74G>C (p=0.18, OR=0.67 95% CI 0.37-1.21) and +140A>G (p=0.416, OR=0.77 95% CI 0.41-1.45) did not affect the risk of urinary bladder cancer. In conclusion, we found that the TGFB1 c.29C>T substitution increases the risk of bladder cancer significantly while c.74G>C and +140A>G polymorphisms do not affect the risk. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Advantages of cross-polarization endoscopic optical coherence tomography in diagnosis of bladder neoplasia

    Science.gov (United States)

    Gladkova, N. D.; Zagaynova, E. V.; Streltsova, O. S.; Kiseleva, E. B.; Karabut, M. M.; Snopova, L. B.; Yunusova, E. E.; Tararova, E.; Gelikonov, V. M.

    2010-02-01

    We consider the cross-polarization OCT (CP OCT) that is focused on comparison of images resulting from cross-polarization and co-polarization scattering simultaneously. This technique provides information about microstructural and biochemical alterations in depolarizing tissue components (collagen). We found that mature type I collagen gives a strong signal in orthogonal polarization. CP OCT images of benign inflammatory processes always feature signal in orthogonal polarization, with layers and borders persisting to be well defined. In the presence of precancerous alterations, signal in orthogonal polarization is available in the image but it is irregular, disappearing in some areas. A CP OCT image of bladder cancer in orthogonal polarization either shows no signal at all or a weak signal.

  10. Low-dose x-ray phase-contrast and absorption CT using equally sloped tomography

    International Nuclear Information System (INIS)

    Fahimian, Benjamin P; Miao Jianwei; Mao Yu; Cloetens, Peter

    2010-01-01

    Tomographic reconstruction from undersampled and noisy projections is often desirable in transmission CT modalities for purposes of low-dose tomography and fast acquisition imaging. However under such conditions, due to the violation of the Nyquist sampling criteria and the presence of noise, reconstructions with acceptable accuracy may not be possible. Recent experiments in transmission electron tomography and coherent diffraction microscopy have shown that the technique of equally sloped tomography (EST), an exact tomographic method utilizing an oversampling iterative Fourier-based reconstruction, provides more accurate image reconstructions when the number of projections is significantly undersampled relative to filtered back projection and algebraic iterative methods. Here we extend this technique by developing new reconstruction algorithms which allow for the incorporation of advanced mathematical regularization constraints, such as the nonlocal means total variational model, in a manner that is consistent with experimental projections. We then evaluate the resulting image quality of the developed algorithm through simulations and experiments at the European Synchrotron Radiation Facility on image quality phantoms using the x-ray absorption and phase contrast CT modalities. Both our simulation and experimental results have indicated that the method can reduce the number of projections by 60-75% in parallel beam modalities, while achieving comparable or better image quality than the conventional reconstructions. As large-scale and compact synchrotron radiation facilities are currently under rapid development worldwide, the implementation of low-dose x-ray absorption and phase-contrast CT can find broad applications in biology and medicine using these advanced x-ray sources.

  11. High-resolution computed tomography of cholesteatoma of the middle ear. CT, otological, and surgical correlation

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, Kiyoshi; Fukusumi, Akio; Okudera, Toshio; Kato, Toshihiko; Soda, Toyoji

    1988-08-01

    The high-resolution computed tomography (CT) appearances of 72 consecutive cases (92 ears) of chronic otomastoiditis were reviewed. The cholesteatomas were verified surgically and/or otologically in 35 of these 92 ears. Discussion was made with special emphasis on the differential diagnosis of cholesteatoma of the middle ear from the non-cholesteatoma otitis media. The CT findings suggestive of cholesteatoma were as follows: the definitive findings was of a soft-tissue opacity filling Purssak's space, with a medial displacement of the malleus and the incus; the possible findings were 1) a bony erosion of the wall of the middle ear cavity, 2) a partial or complete disappearance of the malleus and/or the incus, and 3) an opacification of Purssak's space and the superomedial aspect of the external auditory meatus.

  12. Abdominal and pelvic computed tomography (CT) interpretation: discrepancy rates among experienced radiologists

    Energy Technology Data Exchange (ETDEWEB)

    Abujudeh, Hani H.; Boland, Giles W.; Kaewlai, Rathachai; Rabiner, Pavel; Thrall, James H. [Massachusetts General Hospital and Harvard Medical School, Department of Radiology, Boston, MA (United States); Halpern, Elkarn F.; Gazelle, G.S. [Massachusetts General Hospital and Harvard Medical School, Department of Radiology, Boston, MA (United States); Massachusetts General Hospital and Harvard Medical School, Institute for Technology Assessment, Boston, MA (United States)

    2010-08-15

    To assess the discrepancy rate for the interpretation of abdominal and pelvic computed tomography (CT) examinations among experienced radiologists. Ninety abdominal and pelvic CT examinations reported by three experienced radiologists who specialize in abdominal imaging were randomly selected from the radiological database. The same radiologists, blinded to previous interpretation, were asked to re-interpret 60 examinations: 30 of their previous interpretations and 30 interpreted by others. All reports were assessed for the degree of discrepancy between initial and repeat interpretations according to a three-level scoring system: no discrepancy, minor, or major discrepancy. Inter- and intrareader discrepancy rates and causes were evaluated. CT examinations included in the investigation were performed on 90 patients (43 men, mean age 59 years, SD 14, range 19-88) for the following indications: follow-up/evaluation of malignancy (69/90, 77%), pancreatitis (5/90, 6%), urinary tract stone (4/90, 4%) or other (12/90, 13%). Interobserver and intraobserver major discrepancy rates were 26 and 32%, respectively. Major discrepancies were due to missed findings, different opinions regarding interval change of clinically significant findings, and the presence of recommendation. Major discrepancy of between 26 and 32% was observed in the interpretation of abdominal and pelvic CT examinations. (orig.)

  13. Computed tomography (CT), nuclear medicine (NM), and ultrasound (US) in oncology patients

    International Nuclear Information System (INIS)

    McNeil, B.J.

    1982-01-01

    This review will summarize the effectiveness of computed tomography, ultrasound, and nuclear medicine imaging procedures in several different disease processes. The results indicate: (1) CT is clearly better than ultrasound for diseases of the adrenal gland and pancreas; (2) for patients with gynecologic malignancies, CT and ultrasound are approximately equivalent in their ability to define treatment options effectively; (3) in the liver, the differences among the three modalities are less marked and are disease specific. For example, for patients with colon cancer the increased effectiveness of CT relative to ultrasound or nuclear medicine is small. For patients with breast cancer, the difference is greater; (4) for patients suspected to have a focal source of sepsis, CT is slightly better than ultrasound or nuclear medicine. In these patients, however, when nuclear medicine images are obtained on a rectilinear scanner, the results are significantly worse compared to nuclear medicine images on a LFOV gamma camera or to ultrasound. As a result of the above studies and concommitant statistical analyses, several conclusions can be drawn about optimum experimental design and statistical approaches for comparing imaging modalities

  14. Clinical value of {sup 18}F-fluorodihydroxyphenylalanine positron emission tomography/computed tomography ({sup 18}F-DOPA PET/CT) for detecting pheochromocytoma

    Energy Technology Data Exchange (ETDEWEB)

    Luster, Markus; Zeich, Katrin; Glatting, Gerhard; Buck, Andreas K.; Solbach, Christoph; Reske, Sven N. [University of Ulm, Department of Nuclear Medicine, Ulm (Germany); Karges, Wolfram [RWTH Aachen, Division of Endocrinology and Diabetes, Aachen (Germany); Pauls, Sandra [University of Ulm, Department of Radiology, Ulm (Germany); Verburg, Frederik A. [University of Wuerzburg, Department of Nuclear Medicine, Wuerzburg (Germany); Dralle, Henning [University Halle-Wittenberg, Department of General, Visceral and Vascular Surgery, Halle (Germany); Neumaier, Bernd [University of Ulm, Department of Nuclear Medicine, Ulm (Germany); Max-Planck-Institut fuer Neurologische Forschung, Section for Radiochemistry, Cologne (Germany); Mottaghy, Felix M. [University of Ulm, Department of Nuclear Medicine, Ulm (Germany); RWTH Aachen, Department of Nuclear Medicine, Aachen (Germany)

    2010-03-15

    In detecting pheochromocytoma (PHEO), positron emission tomography (PET) with the radiolabelled amine precursor {sup 18}F-fluorodihydroxyphenylalanine ({sup 18}F-DOPA) offers excellent specificity, while computed tomography (CT) provides high sensitivity and ability to localize lesions; therefore, the combination of these modalities could be advantageous in this setting. The aim of this study was to investigate whether combined {sup 18}F-DOPA PET/CT more accurately detects and localizes PHEO lesions than does each modality alone. {sup 18}F-DOPA PET, CT and {sup 18}F-DOPA PET/CT images of 25 consecutive patients undergoing diagnostic scanning of suspected sporadic or multiple endocrine neoplasia type 2 syndrome-associated PHEO were reviewed retrospectively in randomized sequence. Two blinded observers scored the images regarding the likelihood of PHEO being present and localizable. Results were correlated with subsequent clinical history and, when available, histology. Of the 19 lesions detected by all three modalities, PET identified each as positive for PHEO, but was unable to definitively localize 15 of 19 (79%). CT could definitively localize all 19 lesions, but could not definitively diagnose or exclude PHEO in 18 of 19 (95%) lesions. Furthermore, CT falsely identified as negative for PHEO one lesion which was judged to be positive for this tumor by both PET and PET/CT. Only in PET/CT scans were all 19 lesions accurately characterized and localized. On a per-patient basis, the sensitivity of {sup 18}F-DOPA PET/CT for PHEO was 100% and the specificity 88%, with a 100% positive predictive value and an 88% negative predictive value. {sup 18}F-DOPA PET/CT more accurately diagnoses and localizes adrenal and extra-adrenal masses suspicious for PHEO than do {sup 18}F-DOPA PET or CT alone. (orig.)

  15. Clinical value of 18F-fluorodihydroxyphenylalanine positron emission tomography/computed tomography (18F-DOPA PET/CT) for detecting pheochromocytoma

    International Nuclear Information System (INIS)

    Luster, Markus; Zeich, Katrin; Glatting, Gerhard; Buck, Andreas K.; Solbach, Christoph; Reske, Sven N.; Karges, Wolfram; Pauls, Sandra; Verburg, Frederik A.; Dralle, Henning; Neumaier, Bernd; Mottaghy, Felix M.

    2010-01-01

    In detecting pheochromocytoma (PHEO), positron emission tomography (PET) with the radiolabelled amine precursor 18 F-fluorodihydroxyphenylalanine ( 18 F-DOPA) offers excellent specificity, while computed tomography (CT) provides high sensitivity and ability to localize lesions; therefore, the combination of these modalities could be advantageous in this setting. The aim of this study was to investigate whether combined 18 F-DOPA PET/CT more accurately detects and localizes PHEO lesions than does each modality alone. 18 F-DOPA PET, CT and 18 F-DOPA PET/CT images of 25 consecutive patients undergoing diagnostic scanning of suspected sporadic or multiple endocrine neoplasia type 2 syndrome-associated PHEO were reviewed retrospectively in randomized sequence. Two blinded observers scored the images regarding the likelihood of PHEO being present and localizable. Results were correlated with subsequent clinical history and, when available, histology. Of the 19 lesions detected by all three modalities, PET identified each as positive for PHEO, but was unable to definitively localize 15 of 19 (79%). CT could definitively localize all 19 lesions, but could not definitively diagnose or exclude PHEO in 18 of 19 (95%) lesions. Furthermore, CT falsely identified as negative for PHEO one lesion which was judged to be positive for this tumor by both PET and PET/CT. Only in PET/CT scans were all 19 lesions accurately characterized and localized. On a per-patient basis, the sensitivity of 18 F-DOPA PET/CT for PHEO was 100% and the specificity 88%, with a 100% positive predictive value and an 88% negative predictive value. 18 F-DOPA PET/CT more accurately diagnoses and localizes adrenal and extra-adrenal masses suspicious for PHEO than do 18 F-DOPA PET or CT alone. (orig.)

  16. Influence of bladder distension on opacification of urinary collecting system during CT urography

    Energy Technology Data Exchange (ETDEWEB)

    Curic, Josip; Vukelic-Markovic, Mirjana; Marusic, Petar; Hrkac-Pustahija, Ana; Brkljacic, Boris [University Hospital Dubrava, Department of Diagnostic and Interventional Radiology, Zagreb (Croatia)

    2008-05-15

    The purpose of the study was to evaluate and compare opacification of the renal collecting system and ureters detected by computed tomographic urography (CTU) performed 20 min and 1 h after the ingestion of 1,000 ml of water. CTU was performed on 89 patients (55 men, 34 women; age 28-77 years) and 168 collecting systems and ureters were evaluated. A 16-detector-row scanner (Sensation 16, Siemens) was used; a two-phase protocol with a split bolus of contrast agent (total 120 ml) was applied. A combined nephrographic-excretory phase was obtained 100 s after the second injection. Three-dimensional reconstructions of the excretory phase were created and used to evaluate the degree of opacification of the collecting system and ureters. In 44 patients, water was administered 20 min before examination, and in 45 patients, 1 h before examination. CTU performed 1 h after water ingestion demonstrated complete opacification of calices in 87.5%, of renal pelvis in 97.5%, of upper ureter in 91.8% and of lower ureter in 87.5% of patients. CTU performed 20 min after water ingestion demonstrated complete opacification of calices in 79.5%, of renal pelvis in 85%, of upper ureter in 62.5% and of lower ureter in 54.5% of patients. Complete opacification of the proximal and distal ureter in the group with a 1-h delay was statistically higher (P < 0.01). CTU performed on the distended bladder, 1 h after the oral ingestion of water, enables excellent opacification of collecting system, including distal ureters. (orig.)

  17. Bladder filling variations during concurrent chemotherapy and pelvic radiotherapy in rectal cancer patients: early experience of bladder volume assessment using ultrasound scanner

    International Nuclear Information System (INIS)

    Chang, Jee Suk; Yoon, Hong In; Cha, Hye Jung; Chang, Yoon Sun; Cho, Yeo Na; Keum, Ki Chang; Koom, Woong Sub

    2013-01-01

    To describe the early experience of analyzing variations and time trends in bladder volume of the rectal cancer patients who received bladder ultrasound scan. We identified 20 consecutive rectal cancer patients who received whole pelvic radiotherapy (RT) and bladder ultrasound scan between February and April 2012. Before simulation and during the entire course of treatment, patients were scanned with portable automated ultrasonic bladder scanner, 5 times consecutively, and the median value was reported. Then a radiation oncologist contoured the bladder inner wall shown on simulation computed tomography (CT) and calculated its volume. Before simulation, the median bladder volume measured using simulation CT and bladder ultrasound scan was 427 mL (range, 74 to 1,172 mL) and 417 mL (range, 147 to 1,245 mL), respectively. There was strong linear correlation (R = 0.93, p < 0.001) between the two results. During the course of treatment, there were wide variations in the bladder volume and every time, measurements were below the baseline with statistical significance (12/16). At 6 weeks after RT, the median volume was reduced by 59.3% to 175 mL. Compared to the baseline, bladder volume was reduced by 38% or 161 mL on average every week for 6 weeks. To our knowledge, this study is the first to prove that there are bladder volume variations and a reduction in bladder volume in rectal cancer patients. Moreover, our results will serve as the basis for implementation of bladder training to patients receiving RT with full bladder.

  18. Adaptive radiotherapy for invasive bladder cancer: A feasibility study

    International Nuclear Information System (INIS)

    Pos, Floris J.; Hulshof, Maarten; Lebesque, Joos; Lotz, Heidi; Tienhoven, Geertjan van; Moonen, Luc; Remeijer, Peter

    2006-01-01

    Purpose: To evaluate the feasibility of adaptive radiotherapy (ART) in combination with a partial bladder irradiation. Methods and Materials: Twenty-one patients with solitary T1-T4 N0M0 bladder cancer were treated to the bladder tumor + 2 cm margin planning target volume (PTV CONV ). During the first treatment week, five daily computed tomography (CT) scans were made immediately before or after treatment. In the second week, a volume was constructed encompassing the gross tumor volumes (GTVs) on the planning scan and the five CT scans (GTV ART ). The GTV ART was expanded with a 1 cm margin for the construction of a PTV ART . Starting in the third week, patients were treated to PTV ART . Repeat CT scans were used to evaluate treatment accuracy. Results: On 5 of 91 repeat CT scans (5%), the GTV was not adequately covered by the PTV ART . On treatment planning, there was only one scan in which the GTV was not adequately covered by the 95% isodose. On average, the treatment volumes were reduced by 40% when comparing PTV ART with PTV CONV (p < 0.0001). Conclusion: The adaptive strategy for bladder cancer is an effective way to deal with treatment errors caused by variations in bladder tumor position and leads to a substantial reduction in treatment volumes

  19. Clinical manifestations that predict abnormal brain computed tomography (CT in children with minor head injury

    Directory of Open Access Journals (Sweden)

    Nesrin Alharthy

    2015-01-01

    Full Text Available Background: Computed tomography (CT used in pediatric pediatrics brain injury (TBI to ascertain neurological manifestations. Nevertheless, this practice is associated with adverse effects. Reports in the literature suggest incidents of morbidity and mortality in children due to exposure to radiation. Hence, it is found imperative to search for a reliable alternative. Objectives: The aim of this study is to find a reliable clinical alternative to detect an intracranial injury without resorting to the CT. Materials and Methods: Retrospective cross-sectional study was undertaken in patients (1-14 years with blunt head injury and having a Glasgow Coma Scale (GCS of 13-15 who had CT performed on them. Using statistical analysis, the correlation between clinical examination and positive CT manifestation is analyzed for different age-groups and various mechanisms of injury. Results: No statistically significant association between parameteres such as Loss of Consciousness, ′fall′ as mechanism of injury, motor vehicle accidents (MVA, more than two discrete episodes of vomiting and the CT finding of intracranial injury could be noted. Analyzed data have led to believe that GCS of 13 at presentation is the only important clinical predictor of intracranial injury. Conclusion: Retrospective data, small sample size and limited number of factors for assessing clinical manifestation might present constraints on the predictive rule that was derived from this review. Such limitations notwithstanding, the decision to determine which patients should undergo neuroimaging is encouraged to be based on clinical judgments. Further analysis with higher sample sizes may be required to authenticate and validate findings.

  20. Radiation absorbed from dental implant radiography: a comparison of linear tomography, CT scan, and panoramic and intra-oral techniques

    Energy Technology Data Exchange (ETDEWEB)

    Clark, D.E.; Danforth, R.A.; Barnes, R.W.; Burtch, M.L. (Loma Linda Univ., CA (USA))

    1990-01-01

    Absorbed radiation dose in bone marrow, thyroid, salivary gland, eye, and skin entrance was determined by placement of lithium fluoride thermoluminescent dosimeters (TLD's) at selected anatomical sites within and on a human-like x-ray phantom. The phantom was exposed to radiation from linear tomographic and computer-assisted tomographic (CT) simulated dental implant radiographic examinations. The mean dose was determined for each anatomical site. Resulting dose measurements from linear tomography and computer-assisted tomography are compared with reported panoramic and intra-oral doses. CT examination delivered the greatest dose, while linear tomography was generally lowest. Panoramic and intra-oral doses were similar to those of linear tomography.

  1. Bone regeneration assessment by optical coherence tomography and MicroCT synchrotron radiation

    Science.gov (United States)

    Negrutiu, Meda L.; Sinescu, Cosmin; Canjau, Silvana; Manescu, Adrian; Topalá, Florin I.; Hoinoiu, Bogdan; Romînu, Mihai; Márcáuteanu, Corina; Duma, Virgil; Bradu, Adrian; Podoleanu, Adrian G.

    2013-06-01

    Bone grafting is a commonly performed surgical procedure to augment bone regeneration in a variety of orthopaedic and maxillofacial procedures, with autologous bone being considered as the "gold standard" bone-grafting material, as it combines all properties required in a bone-graft material: osteoinduction (bone morphogenetic proteins - BMPs - and other growth factors), osteogenesis (osteoprogenitor cells) and osteoconduction (scaffold). The problematic elements of bone regenerative materials are represented by their quality control methods, the adjustment of the initial bone regenerative material, the monitoring (noninvasive, if possible) during their osteoconduction and osteointegration period and biomedical evaluation of the new regenerated bone. One of the research directions was the interface investigation of the regenerative bone materials and their behavior at different time periods on the normal femoral rat bone. 12 rat femurs were used for this investigation. In each ones a 1 mm diameter hole were drilled and a bone grafting material was inserted in the artificial defect. The femurs were removed after one, three and six months. The defects repaired by bone grafting material were evaluated by optical coherence tomography working in Time Domain Mode at 1300 nm. Three dimensional reconstructions of the interfaces were generated. The validations of the results were evaluated by microCT. Synchrotron Radiation allows achieving high spatial resolution images to be generated with high signal-to-noise ratio. In addition, Synchrotron Radiation allows acquisition of volumes at different energies and volume subtraction to enhance contrast. Evaluation of the bone grafting material/bone interface with noninvasive methods such as optical coherence tomography could act as a valuable procedure that can be use in the future in the usual clinical techniques. The results were confirmed by microCT. Optical coherence tomography can be performed in vivo and can provide a

  2. Computed tomography (CT) findings of the pleural metastasis effusion: the examination of 100 patients

    International Nuclear Information System (INIS)

    Arenas, J. J.; Alonso, S.; Gil, S.; Fernandez, F.; Lloret, M.

    1999-01-01

    To evaluate the computed tomography (CT) findings in a series of 100 pleural metastasis effusions. A retrospective study was carried out that consisted of assessing the CT images of 100 malignant pleural metastasis effusions, evaluating the amount of the effusion, its distribution, the presence of swelling or nodules in the different pleural surfaces, the existence and the characteristics of the extrapleural fat and the changes in other locations different to the pleural cavity, mainly the mediastinum and the pulmonary parenchyma. The effusion was located in 12 patients. The amount of the effusion was slight in 14% and massive in 10% of the sick patients. Pleural nodules were detected in 19% of the studies, in all those that affected the costal parental pleura, being less frequent in the other pleural surfaces. The costal parental pleura was swollen in 43% of the sick patients. 52 sick patients did not have any swelling nor pleural nodules, with the pleural effusion being the only sign of pleural metastasis. Changes in the rest of the thorax were frequent in relation to the malignant illness that causes the effusion and appeared in 67% of the sick patients. The patients with pleural effusions of malignant etiology showed variable CT findings, that in general were non-specific, and in almost half the cases no pleural changes can be seen apart from the effusion. (Author) 13 refs

  3. Cerebral blood volume imaging by flat detector computed tomography in comparison to conventional multislice perfusion CT

    International Nuclear Information System (INIS)

    Struffert, Tobias; Kloska, Stephan; Engelhorn, Tobias; Doerfler, Arnd; Deuerling-Zheng, Yu; Boese, Jan; Zellerhoff, Michael; Schwab, Stefan

    2011-01-01

    We tested the hypothesis that Flat Detector computed tomography (FD-CT) with intravenous contrast medium would allow the calculation of whole brain cerebral blood volume (CBV) mapping (FD-CBV) and would correlate with multislice Perfusion CT (PCT). Twenty five patients were investigated with FD-CBV and PCT. Correlation of the CBV maps of both techniques was carried out with measurements from six anatomical regions from both sides of the brain. Mean values of each region and the correlation coefficient were calculated. Bland-Altman analysis was performed to compare the two different imaging techniques. The image and data quality of both PCT and FD-CBV were suitable for evaluation in all patients. The mean CBV values of FD-CBV and PCT showed only minimal differences with overlapping standard deviation. The correlation coefficient was 0.79 (p < 0.01). Bland-Altman analysis showed a mean difference of -0.077 ± 0.48 ml/100 g between FD-CBV and PCT CBV measurements, indicating that FD-CBV values were only slightly lower than those of PCT. CBV mapping with intravenous contrast medium using Flat Detector CT compared favourably with multislice PCT. The ability to assess cerebral perfusion within the angiographic suite may improve the management of ischaemic stroke and evaluation of the efficacy of dedicated therapies. (orig.)

  4. Don’t get caught out! A rare case of a calcified urachal remnant mimicking a bladder calculus

    Science.gov (United States)

    Rodrigues, Jonathan Carl Luis; Gandhi, Sanjay

    2013-01-01

    Computer tomography through the kidneys, ureters and bladder (CT KUB) is the mainstay investigation of suspected renal tract calculi. However, several pathologies other than renal tract calculi can cause apparent urinary bladder calcification. We describe the case of a 45 year old man who presented with left sided renal colic. Prone CT KUB performed on admission revealed a calcified urachal remnant mimicking a urinary bladder calculus in the dependent portion of the urinary bladder, confirmed by reviewing the multi-planar reformatted images. This is the first reported case in the literature of this phenomenon. We discuss the importance of using multi-planar reformatted images (MPR) and maximum intensity projection images (MIP), as well as careful review of previous imaging, in making the correct diagnosis. We also discuss the differential diagnoses that should be considered when presented with urinary bladder calcification. PMID:23705044

  5. Development of a Radiation Dose Reporting Software for X-ray Computed Tomography (CT)

    Science.gov (United States)

    Ding, Aiping

    X-ray computed tomography (CT) has experienced tremendous technological advances in recent years and has established itself as one of the most popular diagnostic imaging tools. While CT imaging clearly plays an invaluable role in modern medicine, its rapid adoption has resulted in a dramatic increase in the average medical radiation exposure to the worldwide and United States populations. Existing software tools for CT dose estimation and reporting are mostly based on patient phantoms that contain overly simplified anatomies insufficient in meeting the current and future needs. This dissertation describes the development of an easy-to-use software platform, “VirtualDose”, as a service to estimate and report the organ dose and effective dose values for patients undergoing the CT examinations. “VirtualDose” incorporates advanced models for the adult male and female, pregnant women, and children. To cover a large portion of the ignored obese patients that frequents the radiology clinics, a new set of obese male and female phantoms are also developed and applied to study the effects of the fat tissues on the CT radiation dose. Multi-detector CT scanners (MDCT) and clinical protocols, as well as the most recent effective dose algorithms from the International Commission on Radiological Protection (ICRP) Publication 103 are adopted in “VirtualDose” to keep pace with the MDCT development and regulatory requirements. A new MDCT scanner model with both body and head bowtie filter is developed to cover both the head and body scanning modes. This model was validated through the clinical measurements. A comprehensive slice-by-slice database is established by deriving the data from a larger number of single axial scans simulated on the patient phantoms using different CT bowtie filters, beam thicknesses, and different tube voltages in the Monte Carlo N-Particle Extended (MCNPX) code. When compared to the existing CT dose software packages, organ dose data in this

  6. Semi-automated method to measure pneumonia severity in mice through computed tomography (CT) scan analysis

    Science.gov (United States)

    Johri, Ansh; Schimel, Daniel; Noguchi, Audrey; Hsu, Lewis L.

    2010-03-01

    Imaging is a crucial clinical tool for diagnosis and assessment of pneumonia, but quantitative methods are lacking. Micro-computed tomography (micro CT), designed for lab animals, provides opportunities for non-invasive radiographic endpoints for pneumonia studies. HYPOTHESIS: In vivo micro CT scans of mice with early bacterial pneumonia can be scored quantitatively by semiautomated imaging methods, with good reproducibility and correlation with bacterial dose inoculated, pneumonia survival outcome, and radiologists' scores. METHODS: Healthy mice had intratracheal inoculation of E. coli bacteria (n=24) or saline control (n=11). In vivo micro CT scans were performed 24 hours later with microCAT II (Siemens). Two independent radiologists scored the extent of airspace abnormality, on a scale of 0 (normal) to 24 (completely abnormal). Using the Amira 5.2 software (Mercury Computer Systems), a histogram distribution of voxel counts between the Hounsfield range of -510 to 0 was created and analyzed, and a segmentation procedure was devised. RESULTS: A t-test was performed to determine whether there was a significant difference in the mean voxel value of each mouse in the three experimental groups: Saline Survivors, Pneumonia Survivors, and Pneumonia Non-survivors. It was found that the voxel count method was able to statistically tell apart the Saline Survivors from the Pneumonia Survivors, the Saline Survivors from the Pneumonia Non-survivors, but not the Pneumonia Survivors vs. Pneumonia Non-survivors. The segmentation method, however, was successfully able to distinguish the two Pneumonia groups. CONCLUSION: We have pilot-tested an evaluation of early pneumonia in mice using micro CT and a semi-automated method for lung segmentation and scoring system. Statistical analysis indicates that the system is reliable and merits further evaluation.

  7. Multi-modal anatomical optical coherence tomography and CT for in vivo dynamic upper airway imaging

    Science.gov (United States)

    Balakrishnan, Santosh; Bu, Ruofei; Price, Hillel; Zdanski, Carlton; Oldenburg, Amy L.

    2017-02-01

    We describe a novel, multi-modal imaging protocol for validating quantitative dynamic airway imaging performed using anatomical Optical Coherence Tomography (aOCT). The aOCT system consists of a catheter-based aOCT probe that is deployed via a bronchoscope, while a programmable ventilator is used to control airway pressure. This setup is employed on the bed of a Siemens Biograph CT system capable of performing respiratory-gated acquisitions. In this arrangement the position of the aOCT catheter may be visualized with CT to aid in co-registration. Utilizing this setup we investigate multiple respiratory pressure parameters with aOCT, and respiratory-gated CT, on both ex vivo porcine trachea and live, anesthetized pigs. This acquisition protocol has enabled real-time measurement of airway deformation with simultaneous measurement of pressure under physiologically relevant static and dynamic conditions- inspiratory peak or peak positive airway pressures of 10-40 cm H2O, and 20-30 breaths per minute for dynamic studies. We subsequently compare the airway cross sectional areas (CSA) obtained from aOCT and CT, including the change in CSA at different stages of the breathing cycle for dynamic studies, and the CSA at different peak positive airway pressures for static studies. This approach has allowed us to improve our acquisition methodology and to validate aOCT measurements of the dynamic airway for the first time. We believe that this protocol will prove invaluable for aOCT system development and greatly facilitate translation of OCT systems for airway imaging into the clinical setting.

  8. A simulation study on proton computed tomography (CT) stopping power accuracy using dual energy CT scans as benchmark

    DEFF Research Database (Denmark)

    Hansen, David Christoffer; Seco, Joao; Sørensen, Thomas Sangild

    2015-01-01

    of detectors and the corresponding noise characteristics. Stopping power maps were calculated for all three scans, and compared with the ground truth stopping power from the phantoms. Results. Proton CT gave slightly better stopping power estimates than the dual energy CT method, with root mean square errors...... development) have both been proposed as methods for obtaining patient stopping power maps. The purpose of this work was to assess the accuracy of proton CT using dual energy CT scans of phantoms to establish reference accuracy levels. Material and methods. A CT calibration phantom and an abdomen cross section...... phantom containing inserts were scanned with dual energy and single energy CT with a state-of-the-art dual energy CT scanner. Proton CT scans were simulated using Monte Carlo methods. The simulations followed the setup used in current prototype proton CT scanners and included realistic modeling...

  9. Isolated Inguinal Bladder Hernia

    OpenAIRE

    BAYSAL, Tamer; SOYLU, Ahmet; ERDOĞAN, Özgül

    2010-01-01

    Isolated urinary bladder herniation into the inguinal canal is rare. It is often diagnosed intraoperatively during surgery or is identified after intraoperative injury. Early diagnosis with radiologic imaging is important to avoid complications during repair surgery. Computed tomography seems the best imaging choice to outline the details of herniation. We report an incidentally discovered case of inguinal bladder herniation with intravenous pyelography and computed tomography findings. ...

  10. Image-Guided Radiation Therapy for Muscle-Invasive Carcinoma of the Urinary Bladder with Cone Beam CT Scan: Use of Individualized Internal Target Volumes for a Single Patient

    Directory of Open Access Journals (Sweden)

    Gagan Saini

    2012-09-01

    Full Text Available Introduction: While planning radiation therapy (RT for a carcinoma of the urinary bladder (CaUB, the intra-fractional variation of the urinary bladder (UB volume due to filling-up needs to be accounted for. This internal target volume (ITV is obtained by adding internal margins (IM to the contoured bladder. This study was planned to propose a method of acquiring individualized ITVs for each patient and to verify their reproducibility. Methods: One patient with CaUB underwent simulation with the proposed ‘bladder protocol’. After immobilization, a planning CT scan on empty bladder was done. He was then given 300 ml of water to drink and the time (T was noted. Planning CT scans were performed after 20 min (T+20, 30 min (T+30 and 40 min (T+40. The CT scan at T+20 was co-registered with the T+30 and T+40 scans. The bladder volumes at 20, 30 and 40 min were then contoured as CTV20, CTV30 and CTV40 to obtain an individualized ITV for our patient. For daily treatment, he was instructed to drink water as above, and the time was noted; treatment was started after 20 min. Daily pre- and post-treatment cone beam CT (CBCT scans were done. The bladder visualized on the pre-treatment CBCT scan was compared with CTV20 and on the post-treatment CBCT scan with CTV30. Results: In total, there were 65 CBCT scans (36 pre- and 29 post-treatment. Individualized ITVs were found to be reproducible in 93.85% of all instances and fell outside in 4 instances. Conclusions: The proposed bladder protocol can yield a reproducible estimation of the ITV during treatment; this can obviate the need for taking standard IMs.

  11. Contribution of computed tomography (CT) in affections of the lung parenchyma in HIV positive patients

    International Nuclear Information System (INIS)

    Neuwirth, J.; Stankova, M.; Spala, J.; Strof, J.

    1996-01-01

    CT findings in HIV positive patients with respiratory complaints were analyzed. The predominant morphological type of changes is a 'ground glass' increased density. Minimal changes of the lung parenchyma were recorded on high resolution computed tomography (HRCT) even in patients with a negative or doubtful finding on plain chest radiographs. Also the range of affections on HRCT scans was wider than on simple scans. The morphological changes on HRCT scans alone, however, are not an adequate basis for differentiation of various infectious agents in inflammatory changes of the lung parenchyma, and frequently mixed infections are involved. When at the same time clinical symptoms are considered, it frequently is possible to considerably reduce the number of possible pathogenic organisms and to start treatment. (author) 4 figs., 11 refs

  12. Tumor motion and deformation during external radiotherapy of bladder cancer

    International Nuclear Information System (INIS)

    Lotz, Heidi T.; Pos, Floris J.; Hulshof, Maarten C.C.M.; Herk, Marcel van; Lebesque, Joos V.; Duppen, Joop C.; Remeijer, Peter

    2006-01-01

    Purpose: First, to quantify bladder-tumor motion in 3 dimensions during a 4-week to 5-week course of external radiotherapy. Second, to relate the motion to the tumor location on the bladder wall. Third, to extensively evaluate gross tumor volume (GTV) shape and volume changes during the course of the treatment. Methods and Materials: Multiple repeat computed tomography (CT) images were obtained for 21 bladder cancer patients. These scans were matched to the rigid bony anatomy. For each patient, the main direction and magnitude of the tumor movement was determined by use of principle-component analysis. To study GTV shape changes, all GTVs were registered to the GTV in the planning CT scan, and the residual shape errors were determined by measurement of edge variations perpendicular to the median surface. Results: Gross tumor volume translations were largest in cranial-caudal and anterior-posterior direction (SD, 0.1 to ∼0.9 cm). The translations were strongly correlated with the tumor location on the bladder wall. The average value of the local standard deviations of the GTV shape ranged from 0.1 to approximately 0.35 cm. Conclusions: Despite large differences in bladder filling, variations in GTV shape were small compared with variations in GTV position. Geometric uncertainties in the GTV position depended strongly on the tumor location on the bladder wall

  13. Free-space fluorescence tomography with adaptive sampling based on anatomical information from microCT

    Science.gov (United States)

    Zhang, Xiaofeng; Badea, Cristian T.; Hood, Greg; Wetzel, Arthur W.; Stiles, Joel R.; Johnson, G. Allan

    2010-02-01

    Image reconstruction is one of the main challenges for fluorescence tomography. For in vivo experiments on small animals, in particular, the inhomogeneous optical properties and irregular surface of the animal make free-space image reconstruction challenging because of the difficulties in accurately modeling the forward problem and the finite dynamic range of the photodetector. These two factors are fundamentally limited by the currently available forward models and photonic technologies. Nonetheless, both limitations can be significantly eased using a signal processing approach. We have recently constructed a free-space panoramic fluorescence diffuse optical tomography system to take advantage of co-registered microCT data acquired from the same animal. In this article, we present a data processing strategy that adaptively selects the optical sampling points in the raw 2-D fluorescent CCD images. Specifically, the general sampling area and sampling density are initially specified to create a set of potential sampling points sufficient to cover the region of interest. Based on 3-D anatomical information from the microCT and the fluorescent CCD images, data points are excluded from the set when they are located in an area where either the forward model is known to be problematic (e.g., large wrinkles on the skin) or where the signal is unreliable (e.g., saturated or low signal-to-noise ratio). Parallel Monte Carlo software was implemented to compute the sensitivity function for image reconstruction. Animal experiments were conducted on a mouse cadaver with an artificial fluorescent inclusion. Compared to our previous results using a finite element method, the newly developed parallel Monte Carlo software and the adaptive sampling strategy produced favorable reconstruction results.

  14. The Modern Art of Reading Computed Tomography Images of the Lungs: Quantitative CT.

    Science.gov (United States)

    Herth, Felix J F; Kirby, Miranda; Sieren, Jered; Herth, Jonas; Schirm, Joshua; Wood, Susan; Schuhmann, Maren

    2018-01-01

    Lung diseases are increasing in prevalence and overall burden worldwide. To stem the tide, more and more national and international guidelines are recommending the use of various diagnostic algorithms that are disease specific. There is growing consensus among the respiratory community that although patient histories and lung function testing are the minimum required for clinical examinations, these tests alone are not sufficient for disease characterization. Therefore, the use of computed tomography (CT) imaging is increasing used in clinical decision making for lung diseases. Lung diseases affect various components of lung, including the small airways, lung parenchyma, the interstitial space and the pulmonary vasculature. Quantitative CT (QCT) methods are emerging and are increasingly available using commercial software to quantify the underlying disease components, and a growing body of evidence suggests that QCT is an important tool in the clinical setting to help accurately and reproducibly detect where the disease is located in the lung, and to quantify the extent and overall severity for several lung diseases. Furthermore, this growing body of evidence has promoted the use of thoracic QCT to the point that it is now considered by many as an indispensable technology for longitudinal analysis and intervention trials. Many QCT imaging measurements are available to the respiratory physician, and the aim of this review is to introduce and describe pulmonary QCT imaging measurements and methodologies. © 2017 S. Karger AG, Basel.

  15. Measurement accuracy of condylar position on reformatted sagittal CT and sagittal tomography

    Energy Technology Data Exchange (ETDEWEB)

    Hiruma, Takayoshi [Showa Univ., Tokyo (Japan). School of Dentistry

    1995-12-01

    The purpose of this study was to compare the measurement accuracy of the condylar position on reformatted sagittal CT with that on sagittal tomography (TG). The CTs were reformatted from the 1 mm thickness/interval coronal scan. The TGs were performed with hypocycloidal motion. Impressions of the joint space were taken in order to estimate the actual dimensions. The errors, differences between the values from the impressions and the values from CTs and TGs, were calculated and analyzed by ANOVA. The results were as follows: The mean measurement error of the condylar position on the CT was 0.1 mm. No statistically significant differences were observed among the CTs reformatted from the coronal scan obtained with the X-ray beam projecting at 90deg, 80deg and 70deg to the F-H plane. The measurement error on the TGs with a mean value of 0.3 mm was larger than that of the CTs. However, one of the 6 TMJs caused a great measurement error on the TG with a mean value of 0.9 mm while the measurement of the other 5 TMJs showed a smaller mean error of 0.1 mm. These findings suggest that the anatomic morphology of TMJs influence the measurement accuracy on the TGs. (author).

  16. A comparison of shielding calculation methods for multi-slice computed tomography (CT) systems

    International Nuclear Information System (INIS)

    Cole, J A; Platten, D J

    2008-01-01

    Currently in the UK, shielding calculations for computed tomography (CT) systems are based on the BIR-IPEM (British Institute of Radiology and Institute of Physics in Engineering in Medicine) working group publication from 2000. Concerns have been raised internationally regarding the accuracy of the dose plots on which this method depends and the effect that new scanner technologies may have. Additionally, more recent shielding methods have been proposed by the NCRP (National Council on Radiation Protection) from the USA. Thermoluminescent detectors (TLDs) were placed in three CT scanner rooms at different positions for several weeks before being processed. Patient workload and dose data (DLP: the dose length product and mAs: the tube current-time product) were collected for this period. Individual dose data were available for more than 95% of patients scanned and the remainder were estimated. The patient workload data were used to calculate expected scatter radiation for each TLD location by both the NCRP and BIR-IPEM methods. The results were then compared to the measured scattered radiation. Calculated scattered air kerma and the minimum required lead shielding were found to be frequently overestimated compared to the measured air kerma, on average almost five times the measured scattered air kerma.

  17. Discrimination of suppurative cholangitis from nonsuppurative cholangitis with computed tomography (CT)

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Nam Kyung [Department of Diagnostic Radiology, Pusan National University Hospital, Pusan National University School of Medicine and Medical Research Institute, Pusan National University, Busan 602-739 (Korea, Republic of); Kim, Suk [Department of Diagnostic Radiology, Pusan National University Hospital, Pusan National University School of Medicine and Medical Research Institute, Pusan National University, Busan 602-739 (Korea, Republic of)], E-mail: kimsuk@medigate.net; Lee, Jun Woo; Kim, Chang Won [Department of Diagnostic Radiology, Pusan National University Hospital, Pusan National University School of Medicine and Medical Research Institute, Pusan National University, Busan 602-739 (Korea, Republic of); Kim, Gwang Ha; Kang, Dae Hwan [Department of Gastrointestinal Internal Medicine, Pusan National University Hospital, Pusan National University School of Medicine and Medical Research Institute, Pusan National University, Busan 602-739 (Korea, Republic of); Jo, Hong Jae [Department of Surgery, Pusan National University Hospital, Pusan National University School of Medicine and Medical Research Institute, Pusan National University, Busan 602-739 (Korea, Republic of)

    2009-03-15

    Purpose: Suppurative cholangitis is characterized by obstruction, inflammation, and pyogenic infection of the biliary tract. This disease represents a true emergency. The purpose of this study was to compare the computed tomography (CT) findings between acute calculous suppurative and nonsuppurative cholangitis and to determine if there are findings that assist in the differential diagnosis. Materials and methods: Fifteen patients with acute suppurative cholangitis were enrolled in this study. Findings at endoscopic retrograde cholangiopancreaticography (ERCP) were the standard of reference for suppurative cholangitis. To compare the findings of suppurative cholangitis with those of nonsuppurative cholangitis, 35 patients with nonsuppurative cholangitis were randomly selected. The following findings were evaluated: the presence of papillitis, the presence of stones in the ampulla, the presence of intrahepatic stones, the presence of early inhomogeneous enhancement of the liver, the degree of bile duct dilatation, the degree of bile duct wall thickening and presence of cholecystitis. Sensitivity and specificity for each of the individual findings were calculated. Statistical analyses were performed the Pearson {chi}{sup 2} test, Fisher's exact test and the Mann-Whitney U test. Results: Papillitis showed the highest specificity 86% with 60% sensitivity. Marked inhomogeneous enhancement of the liver during the arterial phase showed 80% specificity with 60% sensitivity. In multivariate logistic analysis, papillitis and marked early inhomogeneous enhancement of the liver were the most significant predictors of acute suppurative cholangitis. The combination of these two CT findings improved specificity (97% specificity) for the diagnosis of suppurative cholangitis. Conclusion: Papillitis and marked early inhomogeneous enhancement of the liver were found to be the most discriminative CT findings for the diagnosis of acute suppurative cholangitis and the

  18. Comparison study of positron emission tomography, X-ray CT and MRI in Parkinsonism with dementia

    International Nuclear Information System (INIS)

    Okada, Junichi; Peppard, R.; Calne, D.B.

    1989-01-01

    Brain atrophy and local cerebral metabolic rate of glucose (LCMR-glc) in Parkinson's disease with dementia and Parkinsonism-dementia complex (PDC) were studied using positron emission tomography (PET) with F-18-2-deoxy-2-fluoro-D-glucose, X-ray CT and magnetic resonance imaging (MRI). The group of Parkinson's disease with dementia (n=7) had a significantly decreased LCMR-glc in all regions when compared with the age-matched normal group. In the group of Parkinson's disease without dementia (n=6), LCMR-glc was also significantly lower than the control group, although it was higher than the group with associated dementia. Some of the normal aged persons had cortical atrophy. There was no correlation between LCMR-glc and cortical atrophy. Six Guamnian patients had PDC associated with amyotrophic lateral sclerosis (ALS), and four patients had it without ALS. LCMR-glc did not differ in the two groups. It was, however, significantly lower than that in 5 Guamanian and 10 Caucasian normal persons. The group of PDC had a noticeable cortical atrophy and ventricular dilatation, regardless of the presence or absence of ALS. There was correlation between decrease of LCMR-glc and cortical atrophy of the frontal, parietal and temporal lobes. Parkinson's disease and PDC were different from Alzheimer's disease in which a decreased LCMR-glc has been reported to be usually confined to the cerebral cortex. Cortical atrophy and ventricular dilatation were depicted on MRI and CT in the PDC group, but did not in the group of Parkinson's disease. PET was useful in the functional examination and both MRI and CT were useful in the anatomical examination of these diseases. (Namekawa, K)

  19. Isolated thymic Langerhans cell histiocytosis discovered on F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT)

    Energy Technology Data Exchange (ETDEWEB)

    Turpin, Sophie [CHU Sainte-Justine, Nuclear Medicine, Montreal (Canada); Carret, Anne-Sophie [CHU Sainte-Justine, Hemato-Oncology, Montreal (Canada); Dubois, Josee [CHU Sainte-Justine, Radiology, Montreal (Canada); Buteau, Chantal [CHU Sainte-Justine, Infectious Diseases, Montreal (Canada); Patey, Natalie [CHU Sainte-Justine, Pathology, Montreal (Canada)

    2015-11-15

    The thymic infiltration in young patients with multisystemic Langerhans cell histiocytosis and its radiologic features are well known. However, isolated thymic disease has seldom been reported in the literature. We report the case of a 10-month-old child admitted for fever of unknown origin. Whole-body F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) was performed to identify a focus of infection. It demonstrated an unusual aspect of the thymus, which led to further investigation and revealed isolated infiltration of the thymus by Langerhans cell histiocytosis. The patient was treated accordingly and is now disease free. As evaluation of Langerhans cell histiocytosis patients with F-18 FDG PET/CT is becoming more frequent, it is important to be aware of the scintigraphical characteristics of thymic Langerhans cell histiocytosis. (orig.)

  20. Isolated thymic Langerhans cell histiocytosis discovered on F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT).

    Science.gov (United States)

    Turpin, Sophie; Carret, Anne-Sophie; Dubois, Josée; Buteau, Chantal; Patey, Natalie

    2015-11-01

    The thymic infiltration in young patients with multisystemic Langerhans cell histiocytosis and its radiologic features are well known. However, isolated thymic disease has seldom been reported in the literature. We report the case of a 10-month-old child admitted for fever of unknown origin. Whole-body F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) was performed to identify a focus of infection. It demonstrated an unusual aspect of the thymus, which led to further investigation and revealed isolated infiltration of the thymus by Langerhans cell histiocytosis. The patient was treated accordingly and is now disease free. As evaluation of Langerhans cell histiocytosis patients with F-18 FDG PET/CT is becoming more frequent, it is important to be aware of the scintigraphical characteristics of thymic Langerhans cell histiocytosis.