Jonathon Willatt - Academia.edu (original) (raw)

Papers by Jonathon Willatt

Gastrointestinal Oncology, 2008

Page 1. 19 Primary Liver Cancer Edited by Charlie Pan & Theodore Lawrence disease. Table ... more Page 1. 19 Primary Liver Cancer Edited by Charlie Pan & Theodore Lawrence disease. Table 19.1 shows the risk factors for the development of HCC. The largest concentration of cases of liver cancer in the world is in Asia, followed ...

Korean journal of radiology : official journal of the Korean Radiological Society

To evaluate the effect of temporary stent graft placement in the treatment of benign anastomotic ... more To evaluate the effect of temporary stent graft placement in the treatment of benign anastomotic biliary strictures. Nine patients, five women and four men, 22-64 years old (mean, 47.5 years), with chronic benign biliary anastomotic strictures, refractory to repeated balloon dilations, were treated by prolonged, temporary placement of stent-grafts. Four patients had strictures following a liver transplantation; three of them in bilio-enteric anastomoses and one in a choledocho-choledochostomy. Four of the other five patients had strictures at bilio-enteric anastomoses, which developed after complications following laparoscopic cholecystectomies and in one after a Whipple procedure for duodenal carcinoma. In eight patients, balloon-expandable stent-grafts were placed and one patient was treated by insertion of a self-expanding stent-graft. In the transplant group, treatment of patients with bilio-enteric anastomoses was unsuccessful (mean stent duration, 30 days). The patient treated...

Primary Carcinomas of the Liver, 2001

Journal of Vascular and Interventional Radiology, 2010

The present report describes the safe retrieval of caudally migrated optional inferior vena cava ... more The present report describes the safe retrieval of caudally migrated optional inferior vena cava (IVC) filters with significant IVC penetration. Three patients had optional IVC filters placed for deep vein thrombosis/pulmonary emboli and contraindications for anticoagulation. Subsequent imaging showed caudal migration and penetration of the filter legs through the IVC wall. All filters were removed without major complications. One patient experienced abdominal pain after filter removal, which required no treatment. Caudal migration of optional filters with IVC wall penetration by the filter legs may be more common with new filter designs in which the secondary and primary struts are separated. J Vasc Interv Radiol 2010; 21:923-926 Abbreviations: DVT ϭ deep vein thrombosis, IVC ϭ inferior vena cava, PE ϭ pulmonary emboli From the

Australasian Radiology, 2007

To determine first, the accuracy of a gynaecological ultrasound service in the detection of four ... more To determine first, the accuracy of a gynaecological ultrasound service in the detection of four clinically significant pathologies, namely, uterine body malignancy, ovarian malignancy, ovarian dermoid cysts and other benign ovarian pathologies and second, to review the ultrasound imaging appearances of ovarian masses with histopathological correlation. Retrospective data collection from consecutive weekly multidisciplinary team meetings over a 12-month period. All patients had undergone ultrasound examination before surgery. Data included patient demographics, menopausal status, indications for ultrasound, type of practitioner carrying out the scan, operative findings and final histopathological diagnosis. Ultrasound imaging appearances were correlated to histology. Of the 47 cases of uterine malignancy, 45 had endometrial carcinoma. All had either a thickened or poorly seen or not seen endometrium. Twenty-four per cent of these women were premenopausal. Forty-seven of the 48 cases of ovarian malignancy had abnormal ultrasound findings. In six of these, the findings were of a purely cystic lesion. There were 62 cases of benign ovarian pathology (excluding dermoid cyst), all of which had an abnormal ultrasound; 16 of these had possible ultrasound features of malignancy. All 30 cases of ovarian dermoid cyst had an abnormal ultrasound with a specific diagnosis being made in 27. This study shows that ultrasound is accurate in the detection of both endometrial and ovarian disease. The endometrium that is not seen or is poorly seen is an indication for endometrial biopsy in women with postmenopausal bleeding. There is considerable overlap in the ultrasound appearances of benign and malignant ovarian lesions. Ultrasound is a good method for the accurate and specific diagnosis of an ovarian dermoid cyst.

Digestive Surgery, 2003

To develop an experimental model to assess the parietal perfusion pressure (PPP) of the digestive... more To develop an experimental model to assess the parietal perfusion pressure (PPP) of the digestive tract using photoplethysmography. Twenty-two mongrel dogs were used. Progressive external compression was applied to the intestinal wall and the PPP was assessed with photoplethysmography. The study group was divided into two groups. In group 1 PPP was measured at the levels of the stomach, duodenum, jejunum and transverse colon. In group 2 PPP was measured after temporary occlusion of the truncal and marginal circulation of the jejunum to provide further variables. The PPP decreased significantly for each successive distal section. Correlation coefficients and indices for PPP and mean arterial pressures were statistically significant (p < 0.005). Truncal occlusion provoked a drop in PPP whereas marginal occlusion scarcely modified the basal results. Photoplethysmography, through measurements of the residual arterial wave amplitude, is a valid method of determining quantitatively the PPP of the digestive tract and could be useful in a clinical environment.

Clinical Radiology, 2004

Children frequently present with asymptomatic head lumps that have been discovered by their paren... more Children frequently present with asymptomatic head lumps that have been discovered by their parents or by their hairdressers. Other children present with painful lumps or symptoms of intra-cranial masses with calvarial involvement. Imaging plays an important role in the diagnosis of such masses and in subsequent surgical planning. We present a review of the types of lesion that may present in these ways.

Abdominal Radiology, 2016

World journal of hepatology, Jan 28, 2016

Ablative treatment methods have emerged as safe and effective therapies for patients with primary... more Ablative treatment methods have emerged as safe and effective therapies for patients with primary and secondary liver tumors who are not surgical candidates at the time of diagnosis. This article reviews the current literature and describes the techniques, complications and results for radiofrequency ablation, microwave ablation, cryoablation, and irreversible electroporation.

International Journal of Endocrinology, 2015

Contemporary Diagnostic Radiology, 2015

Journal of Magnetic Resonance Imaging

Purpose:The goal of this study was to determine the effect of contrast media on the signal behavi... more Purpose:The goal of this study was to determine the effect of contrast media on the signal behavior of single-shot echo planar imaging (ssEPI) used for abdominal diffusion imaging.Materials and Methods:The signal of an ssEPI spin echo sequence in a water phantom with varying concentrations of gadolinium was modeled with Bloch equations and the predicted behavior validated on a phantom at 1.5T. Six volunteers were given gadolinium contrast and signal intensity (SI) time courses for regions of interest (ROIs) in the liver, pancreas, spleen, renal cortex, and medulla were analyzed. Student's t-test was used to compare precontrast SI to 0, 1, 4, 5, 10, and 13 minutes following contrast.Results:The results show that following contrast ssEPI SI goes through a nadir, recovering differently for each organ. Maximal contrast-related signal losses relative to precontrast signal are 20%, 20%, 53%, and 67% for the liver, pancreas, renal cortex, and medulla, respectively. The SIs remain stati...

World journal of hepatology, Jan 27, 2015

A multidisciplinary approach to the treatment of patients with unresectable hepatocellular carcin... more A multidisciplinary approach to the treatment of patients with unresectable hepatocellular carcinoma (HCC) has led to improvements in screening, detection, and treatments. Interventional techniques include thermal ablation, transarterial chemoembolization, and radioembolization whilst stereotactic body radiation therapy also uses imaging to target the radiation. Both survival rates and cure rates have improved markedly since the introduction of these techniques. This review article describes the image guided techniques used for the treatment of HCC.

American family physician, 2010

The increasing use of cross-sectional imaging has led to an increase in the incidental discovery ... more The increasing use of cross-sectional imaging has led to an increase in the incidental discovery of adrenal masses (adrenal incidentalomas). Although most of these lesions are benign, they often present a diagnostic dilemma. Before creating a management plan, the physician should determine if the lesion is benign or malignant and if the lesion is functioning or nonfunctioning. Incidentally discovered adrenal masses usually are benign adenomas; however, myelolipomas, cysts, hemorrhage, pheochromocytomas, metastases, and adrenocortical carcinomas are also possible. Unenhanced computed tomography and chemical shift magnetic resonance imaging can characterize most adenomas because the lesions have high lipid content. Contrast-enhanced computed tomography can further characterize the adenomas because of the washout characteristics with iodinated intravenous contrast media. Fluorodeoxyglucose- positron emission tomography can be helpful in characterizing some lesions, and biopsy is rarely...

Current Problems in Diagnostic Radiology, 2011

Several noninvasive imaging techniques have been developed and improved over recent years that fa... more Several noninvasive imaging techniques have been developed and improved over recent years that facilitate detection of both vascular and nonvascular postoperative complications as well as diagnosis of diseases related to the transplanted organ itself. In this article, we present a multi-modality review of the spectrum of pathology related to renal transplantation.

Spinal Cord, 2009

Study design: Single-centre, prospective (comparative cohort) clinical study, with ethical approv... more Study design: Single-centre, prospective (comparative cohort) clinical study, with ethical approval and patient consent. Objective: Confirmation of vertebral fracture union can pose significant challenges for clinicians in the management of spinal cord injury and in the decisions around patient mobilization. Bony union is usually assessed with computed tomography (CT). This study hypothesizes that magnetic resonance imaging (MRI) can identify vertebral bone union. Setting: A major spinal injuries unit in the United Kingdom. Method: Patients underwent CT and MRI at 12 weeks post-injury, if conservatively managed, or 12 weeks post-fixation. With CT as the gold standard, the MRI scans were reviewed blind to the CT result and indicators for fracture healing were compared. Results: A total of 35 patients with 55 fractures were imaged. Comparison of CT and MRI showed sensitivity of 88%, specificity of 100% and positive predictive value of 100% for fracture union imaged with MRI using CT as the gold standard. Conclusion: MRI correlates well with CT in identifying vertebral fracture union and non-union. We suggest that where imaging is indicated in the assessment of vertebral body fracture healing MRI can be used routinely with CT reserved for problematic or inconclusive cases.

Radiology, 2008

The incidence of hepatocellular carcinoma (HCC) is expected to increase in the next 2 decades, la... more The incidence of hepatocellular carcinoma (HCC) is expected to increase in the next 2 decades, largely due to hepatitis C infection and secondary cirrhosis. HCC is being detected at an earlier stage owing to the implementation of screening programs. Biopsy is no longer required prior to treatment, and diagnosis of HCC is heavily dependent on imaging characteristics. The most recent recommendations by the American Association for the Study of Liver Diseases (AASLD) state that a diagnosis of HCC can be made if a mass larger than 2 cm shows typical features of HCC (hypervascularity in the arterial phase and washout in the venous phase) at contrast material-enhanced computed tomography or magnetic resonance (MR) imaging or if a mass measuring 1-2 cm shows these features at both modalities. There is an ever-increasing demand on radiologists to detect smaller tumors, when curative therapies are most effective. However, the major difficulty in imaging cirrhosis is the characterization of hypervascular nodules smaller than 2 cm, which often have nonspecific imaging characteristics. The authors present a review of the MR imaging and pathologic features of regenerative nodules and dysplastic nodules and focus on HCC in the cirrhotic liver, with particular reference to small tumors and lesions that may mimic HCC. The authors also review the sensitivity of MR imaging for the detection of these tumors and discuss the staging of HCC and the treatment options in the context of the guidelines of the AASLD and the imaging criteria required by the United Network for Organ Sharing for transplantation. MR findings following ablation and chemoembolization are also reviewed.

Journal of Vascular and Interventional Radiology, 2010

Journal of Medical Imaging and Radiation Oncology, 2009

Primary hepatic lymphoma (PHL) is rare, accounting for less than 1% of all extranodal lymphomas. ... more Primary hepatic lymphoma (PHL) is rare, accounting for less than 1% of all extranodal lymphomas. In this article, we retrospectively reviewed the imaging features of 12 pathologically proven cases of primary hepatic lymphoma.

Journal of Computer Assisted Tomography, 2008

To investigate changes in usage of computed tomography urography (CTU), indications for CTU, and ... more To investigate changes in usage of computed tomography urography (CTU), indications for CTU, and rates of positive findings over time. Retrospective review of data from April 2000 to December 2005 assessed rates of overall positive findings, rates of suspected transitional cell carcinomas (TCCs), benign genitourinary (GU), and significant non-GU findings. Data were analyzed based on specialty of ordering physicians and on requisition indications. One thousand two hundred seventy-one patients had 1746 CTUs, including 952 men (1259 studies) and 319 women (487 studies) with mean age of 61 years. Computed tomography urographies increased from 265 in 2001 to 443 in 2004. Eighty-nine percent were ordered by urologists, 4% by oncologists, 1% by emergency physicians, and 6% by other specialties. Sixty-two percent of first-time studies were ordered for possible GU malignancy, 24% for hematuria, and 14% for other reasons. Eight hundred sixty-one examinations (49%) showed significant findings. The rate of all positive examinations, analyzed in 6-month periods, varied from 37% to 54%, but no time trend was identified. First-time patient examinations had positive examinations in 46% to 62% of cases. Similarly, no trends were found for examinations interpreted as possible TCC (17%-32%), renal stones (9%-18%), renal masses (1%-6%), causes of hematuria (15%-26%), and acute non-GU findings (2%-9%). The rate of positive findings by ordering specialty varied minimally from 49% to 53%. No change occurred in the proportions of indications for CTU over time. In 5 years, the number of CTU examinations per year increased 1.5-fold. The rate of CTU findings positive for suspected TCC, stones, and other causes of hematuria showed no decline or increase. If precautions are taken regarding proper indications for CTU, the overall rates of positive findings may not substantially change over time, thereby only submitting high-risk patients to this examination.

Gastrointestinal Oncology, 2008

Page 1. 19 Primary Liver Cancer Edited by Charlie Pan & Theodore Lawrence disease. Table ... more Page 1. 19 Primary Liver Cancer Edited by Charlie Pan & Theodore Lawrence disease. Table 19.1 shows the risk factors for the development of HCC. The largest concentration of cases of liver cancer in the world is in Asia, followed ...

Korean journal of radiology : official journal of the Korean Radiological Society

To evaluate the effect of temporary stent graft placement in the treatment of benign anastomotic ... more To evaluate the effect of temporary stent graft placement in the treatment of benign anastomotic biliary strictures. Nine patients, five women and four men, 22-64 years old (mean, 47.5 years), with chronic benign biliary anastomotic strictures, refractory to repeated balloon dilations, were treated by prolonged, temporary placement of stent-grafts. Four patients had strictures following a liver transplantation; three of them in bilio-enteric anastomoses and one in a choledocho-choledochostomy. Four of the other five patients had strictures at bilio-enteric anastomoses, which developed after complications following laparoscopic cholecystectomies and in one after a Whipple procedure for duodenal carcinoma. In eight patients, balloon-expandable stent-grafts were placed and one patient was treated by insertion of a self-expanding stent-graft. In the transplant group, treatment of patients with bilio-enteric anastomoses was unsuccessful (mean stent duration, 30 days). The patient treated...

Primary Carcinomas of the Liver, 2001

Journal of Vascular and Interventional Radiology, 2010

The present report describes the safe retrieval of caudally migrated optional inferior vena cava ... more The present report describes the safe retrieval of caudally migrated optional inferior vena cava (IVC) filters with significant IVC penetration. Three patients had optional IVC filters placed for deep vein thrombosis/pulmonary emboli and contraindications for anticoagulation. Subsequent imaging showed caudal migration and penetration of the filter legs through the IVC wall. All filters were removed without major complications. One patient experienced abdominal pain after filter removal, which required no treatment. Caudal migration of optional filters with IVC wall penetration by the filter legs may be more common with new filter designs in which the secondary and primary struts are separated. J Vasc Interv Radiol 2010; 21:923-926 Abbreviations: DVT ϭ deep vein thrombosis, IVC ϭ inferior vena cava, PE ϭ pulmonary emboli From the

Australasian Radiology, 2007

To determine first, the accuracy of a gynaecological ultrasound service in the detection of four ... more To determine first, the accuracy of a gynaecological ultrasound service in the detection of four clinically significant pathologies, namely, uterine body malignancy, ovarian malignancy, ovarian dermoid cysts and other benign ovarian pathologies and second, to review the ultrasound imaging appearances of ovarian masses with histopathological correlation. Retrospective data collection from consecutive weekly multidisciplinary team meetings over a 12-month period. All patients had undergone ultrasound examination before surgery. Data included patient demographics, menopausal status, indications for ultrasound, type of practitioner carrying out the scan, operative findings and final histopathological diagnosis. Ultrasound imaging appearances were correlated to histology. Of the 47 cases of uterine malignancy, 45 had endometrial carcinoma. All had either a thickened or poorly seen or not seen endometrium. Twenty-four per cent of these women were premenopausal. Forty-seven of the 48 cases of ovarian malignancy had abnormal ultrasound findings. In six of these, the findings were of a purely cystic lesion. There were 62 cases of benign ovarian pathology (excluding dermoid cyst), all of which had an abnormal ultrasound; 16 of these had possible ultrasound features of malignancy. All 30 cases of ovarian dermoid cyst had an abnormal ultrasound with a specific diagnosis being made in 27. This study shows that ultrasound is accurate in the detection of both endometrial and ovarian disease. The endometrium that is not seen or is poorly seen is an indication for endometrial biopsy in women with postmenopausal bleeding. There is considerable overlap in the ultrasound appearances of benign and malignant ovarian lesions. Ultrasound is a good method for the accurate and specific diagnosis of an ovarian dermoid cyst.

Digestive Surgery, 2003

To develop an experimental model to assess the parietal perfusion pressure (PPP) of the digestive... more To develop an experimental model to assess the parietal perfusion pressure (PPP) of the digestive tract using photoplethysmography. Twenty-two mongrel dogs were used. Progressive external compression was applied to the intestinal wall and the PPP was assessed with photoplethysmography. The study group was divided into two groups. In group 1 PPP was measured at the levels of the stomach, duodenum, jejunum and transverse colon. In group 2 PPP was measured after temporary occlusion of the truncal and marginal circulation of the jejunum to provide further variables. The PPP decreased significantly for each successive distal section. Correlation coefficients and indices for PPP and mean arterial pressures were statistically significant (p < 0.005). Truncal occlusion provoked a drop in PPP whereas marginal occlusion scarcely modified the basal results. Photoplethysmography, through measurements of the residual arterial wave amplitude, is a valid method of determining quantitatively the PPP of the digestive tract and could be useful in a clinical environment.

Clinical Radiology, 2004

Children frequently present with asymptomatic head lumps that have been discovered by their paren... more Children frequently present with asymptomatic head lumps that have been discovered by their parents or by their hairdressers. Other children present with painful lumps or symptoms of intra-cranial masses with calvarial involvement. Imaging plays an important role in the diagnosis of such masses and in subsequent surgical planning. We present a review of the types of lesion that may present in these ways.

Abdominal Radiology, 2016

World journal of hepatology, Jan 28, 2016

Ablative treatment methods have emerged as safe and effective therapies for patients with primary... more Ablative treatment methods have emerged as safe and effective therapies for patients with primary and secondary liver tumors who are not surgical candidates at the time of diagnosis. This article reviews the current literature and describes the techniques, complications and results for radiofrequency ablation, microwave ablation, cryoablation, and irreversible electroporation.

International Journal of Endocrinology, 2015

Contemporary Diagnostic Radiology, 2015

Journal of Magnetic Resonance Imaging

Purpose:The goal of this study was to determine the effect of contrast media on the signal behavi... more Purpose:The goal of this study was to determine the effect of contrast media on the signal behavior of single-shot echo planar imaging (ssEPI) used for abdominal diffusion imaging.Materials and Methods:The signal of an ssEPI spin echo sequence in a water phantom with varying concentrations of gadolinium was modeled with Bloch equations and the predicted behavior validated on a phantom at 1.5T. Six volunteers were given gadolinium contrast and signal intensity (SI) time courses for regions of interest (ROIs) in the liver, pancreas, spleen, renal cortex, and medulla were analyzed. Student's t-test was used to compare precontrast SI to 0, 1, 4, 5, 10, and 13 minutes following contrast.Results:The results show that following contrast ssEPI SI goes through a nadir, recovering differently for each organ. Maximal contrast-related signal losses relative to precontrast signal are 20%, 20%, 53%, and 67% for the liver, pancreas, renal cortex, and medulla, respectively. The SIs remain stati...

World journal of hepatology, Jan 27, 2015

A multidisciplinary approach to the treatment of patients with unresectable hepatocellular carcin... more A multidisciplinary approach to the treatment of patients with unresectable hepatocellular carcinoma (HCC) has led to improvements in screening, detection, and treatments. Interventional techniques include thermal ablation, transarterial chemoembolization, and radioembolization whilst stereotactic body radiation therapy also uses imaging to target the radiation. Both survival rates and cure rates have improved markedly since the introduction of these techniques. This review article describes the image guided techniques used for the treatment of HCC.

American family physician, 2010

The increasing use of cross-sectional imaging has led to an increase in the incidental discovery ... more The increasing use of cross-sectional imaging has led to an increase in the incidental discovery of adrenal masses (adrenal incidentalomas). Although most of these lesions are benign, they often present a diagnostic dilemma. Before creating a management plan, the physician should determine if the lesion is benign or malignant and if the lesion is functioning or nonfunctioning. Incidentally discovered adrenal masses usually are benign adenomas; however, myelolipomas, cysts, hemorrhage, pheochromocytomas, metastases, and adrenocortical carcinomas are also possible. Unenhanced computed tomography and chemical shift magnetic resonance imaging can characterize most adenomas because the lesions have high lipid content. Contrast-enhanced computed tomography can further characterize the adenomas because of the washout characteristics with iodinated intravenous contrast media. Fluorodeoxyglucose- positron emission tomography can be helpful in characterizing some lesions, and biopsy is rarely...

Current Problems in Diagnostic Radiology, 2011

Several noninvasive imaging techniques have been developed and improved over recent years that fa... more Several noninvasive imaging techniques have been developed and improved over recent years that facilitate detection of both vascular and nonvascular postoperative complications as well as diagnosis of diseases related to the transplanted organ itself. In this article, we present a multi-modality review of the spectrum of pathology related to renal transplantation.

Spinal Cord, 2009

Study design: Single-centre, prospective (comparative cohort) clinical study, with ethical approv... more Study design: Single-centre, prospective (comparative cohort) clinical study, with ethical approval and patient consent. Objective: Confirmation of vertebral fracture union can pose significant challenges for clinicians in the management of spinal cord injury and in the decisions around patient mobilization. Bony union is usually assessed with computed tomography (CT). This study hypothesizes that magnetic resonance imaging (MRI) can identify vertebral bone union. Setting: A major spinal injuries unit in the United Kingdom. Method: Patients underwent CT and MRI at 12 weeks post-injury, if conservatively managed, or 12 weeks post-fixation. With CT as the gold standard, the MRI scans were reviewed blind to the CT result and indicators for fracture healing were compared. Results: A total of 35 patients with 55 fractures were imaged. Comparison of CT and MRI showed sensitivity of 88%, specificity of 100% and positive predictive value of 100% for fracture union imaged with MRI using CT as the gold standard. Conclusion: MRI correlates well with CT in identifying vertebral fracture union and non-union. We suggest that where imaging is indicated in the assessment of vertebral body fracture healing MRI can be used routinely with CT reserved for problematic or inconclusive cases.

Radiology, 2008

The incidence of hepatocellular carcinoma (HCC) is expected to increase in the next 2 decades, la... more The incidence of hepatocellular carcinoma (HCC) is expected to increase in the next 2 decades, largely due to hepatitis C infection and secondary cirrhosis. HCC is being detected at an earlier stage owing to the implementation of screening programs. Biopsy is no longer required prior to treatment, and diagnosis of HCC is heavily dependent on imaging characteristics. The most recent recommendations by the American Association for the Study of Liver Diseases (AASLD) state that a diagnosis of HCC can be made if a mass larger than 2 cm shows typical features of HCC (hypervascularity in the arterial phase and washout in the venous phase) at contrast material-enhanced computed tomography or magnetic resonance (MR) imaging or if a mass measuring 1-2 cm shows these features at both modalities. There is an ever-increasing demand on radiologists to detect smaller tumors, when curative therapies are most effective. However, the major difficulty in imaging cirrhosis is the characterization of hypervascular nodules smaller than 2 cm, which often have nonspecific imaging characteristics. The authors present a review of the MR imaging and pathologic features of regenerative nodules and dysplastic nodules and focus on HCC in the cirrhotic liver, with particular reference to small tumors and lesions that may mimic HCC. The authors also review the sensitivity of MR imaging for the detection of these tumors and discuss the staging of HCC and the treatment options in the context of the guidelines of the AASLD and the imaging criteria required by the United Network for Organ Sharing for transplantation. MR findings following ablation and chemoembolization are also reviewed.

Journal of Vascular and Interventional Radiology, 2010

Journal of Medical Imaging and Radiation Oncology, 2009

Primary hepatic lymphoma (PHL) is rare, accounting for less than 1% of all extranodal lymphomas. ... more Primary hepatic lymphoma (PHL) is rare, accounting for less than 1% of all extranodal lymphomas. In this article, we retrospectively reviewed the imaging features of 12 pathologically proven cases of primary hepatic lymphoma.

Journal of Computer Assisted Tomography, 2008

To investigate changes in usage of computed tomography urography (CTU), indications for CTU, and ... more To investigate changes in usage of computed tomography urography (CTU), indications for CTU, and rates of positive findings over time. Retrospective review of data from April 2000 to December 2005 assessed rates of overall positive findings, rates of suspected transitional cell carcinomas (TCCs), benign genitourinary (GU), and significant non-GU findings. Data were analyzed based on specialty of ordering physicians and on requisition indications. One thousand two hundred seventy-one patients had 1746 CTUs, including 952 men (1259 studies) and 319 women (487 studies) with mean age of 61 years. Computed tomography urographies increased from 265 in 2001 to 443 in 2004. Eighty-nine percent were ordered by urologists, 4% by oncologists, 1% by emergency physicians, and 6% by other specialties. Sixty-two percent of first-time studies were ordered for possible GU malignancy, 24% for hematuria, and 14% for other reasons. Eight hundred sixty-one examinations (49%) showed significant findings. The rate of all positive examinations, analyzed in 6-month periods, varied from 37% to 54%, but no time trend was identified. First-time patient examinations had positive examinations in 46% to 62% of cases. Similarly, no trends were found for examinations interpreted as possible TCC (17%-32%), renal stones (9%-18%), renal masses (1%-6%), causes of hematuria (15%-26%), and acute non-GU findings (2%-9%). The rate of positive findings by ordering specialty varied minimally from 49% to 53%. No change occurred in the proportions of indications for CTU over time. In 5 years, the number of CTU examinations per year increased 1.5-fold. The rate of CTU findings positive for suspected TCC, stones, and other causes of hematuria showed no decline or increase. If precautions are taken regarding proper indications for CTU, the overall rates of positive findings may not substantially change over time, thereby only submitting high-risk patients to this examination.