Patient safety event reporting in a large radiology department.

OBJECTIVE: The purpose of this article is to describe our experience developing a Web-based radiology-specific event reporting system. CONCLUSION: The Web-based safety event reporting system has been a valuable tool permitting us to address potential safety concerns in our department.

Percutaneous blunt dissection technique for retrieval of over-the-wire Greenfield filters.

Although the over-the-wire Greenfield filter was designed as a permanent filter, the present report describes two patients who had Greenfield filters percutaneously removed. One was removed at approximately 2,250 days after placement. This patient had developed severe abdominal pain believed to be caused by the filter that resolved after percutaneous filter removal. The second patient had the filter removed 8 months after placement at her request. The technique of filter removal involves the use of large telescoping sheaths to facilitate separation of the filter from the vena caval wall.

Adrenal venous sampling for catecholamines: a normal value study.

CONTEXT: Pheochromocytomas are rare, but potentially fatal, neoplasms. The diagnosis and localization of pheochromocytoma can be challenging, and recently there has been some debate regarding the role for adrenal venous sampling (AVS). The utility of AVS in this setting is hampered by a lack of normative value data for adrenal vein catecholamine concentrations and the reliability of lateralization ratios. We sought to address these concerns by analyzing AVS catecholamine concentrations from patients who did not have pheochromocytoma. DESIGN/SETTING: Eighteen patients underwent successful AVS for evaluation of cortisol-producing adrenal masses. All had normal 24-h urinary excretion of fractionated catecholamines and metanephrines. RESULTS: There was a wide range of catecholamine concentrations in both the right (epinephrine 389-118326 pg/ml; norepinephrine 156-11193 pg/ml) and left (epinephrine 113-9327 pg/ml; norepinephrine 229-2216 pg/ml) adrenal veins. The right adrenal vein-to-left adrenal vein epinephrine gradient was as high as 83:1 (median 2.1:1; P < 0.02). Although less striking, similar findings were also seen for norepinephrine. CONCLUSIONS: This report provides a reference range for adrenal vein catecholamine concentrations in nonpheochromocytoma patients and illustrates the wide variation in epinephrine and norepinephrine concentrations. Epinephrine and norepinephrine concentrations are statistically significantly higher in the right vs. the left adrenal vein; in the case of epinephrine, up to an 83-fold difference was found between the right and left adrenal veins. These data highlight why AVS should not be used in the investigation of adrenal pheochromocytoma.

Comparison of gadodiamide-enhanced MR angiography to intraarterial digital subtraction angiography for evaluation of renal artery stenosis: results of a phase III multicenter trial.

PURPOSE: To evaluate the efficacy and safety of 0.1 mmol/kg gadodiamide administration for contrast-enhanced magnetic resonance angiography (MRA) in detecting hemodynamically relevant renal artery stenosis (RAS) when compared with intraarterial digital subtraction angiography (IA-DSA) as the gold standard. MATERIALS AND METHODS: In a multicenter, controlled study, 395 patients with suspected or known RAS were included. Three independent readers evaluated the MRA images. Two readers evaluated the IA-DSA images and subsequently achieved consensus. The sensitivities and specificities of gadodiamide-enhanced MRA were analyzed at the per-patient and per-vessel levels (exact 1-sided binomial test at alpha = 0.025 with 95% confidence interval). RESULTS: A total of 335 patients who had available standard of truth and MRA tests were included in the all-subjects efficacy population: 55.5% (186/335) men and 44.5% women with a mean age of 63 +/- 13 years (range 17-85 years). The sensitivities and specificities ranged from 81% to 86% for all independent readers at the per-patient analysis based on subjects with the diagnostic images. Similar results were achieved with per-vessel level analysis. Fewer than 1% of patients had adverse event associated with gadodiamide administration. There were no cases of nephrogenic systemic fibrosis (NSF) reported. CONCLUSION: Gadodiamide administration at the labeled dose of 0.1 mmol/kg for contrast-enhanced MRA achieved equivalent results compared to IA-DSA in evaluation of RAS and was well tolerated.

Renal artery revascularization improves heart failure control in patients with atherosclerotic renal artery stenosis.

BACKGROUND: Renal artery stenosis (RAS) impacts the pathogenesis and control of heart failure (HF) and may further contribute to increased cardiovascular morbidity and mortality in HF patients. However, the long-term effects of renal artery revascularization on cardiovascular outcomes in HF patients are not well studied. METHODS: The prevalence of HF and its effects on all-cause mortality were studied in 163 consecutive patients with systemic hypertension and chronic kidney disease (serum creatinine >2 mg/dL) who underwent percutaneous transluminal renal angioplasty (PTRA) with stenting for atherosclerotic RAS. In addition, in 100 patients with RAS and coexistent HF, we compared the impact of medical treatment (n = 50) versus PTRA (n = 50) on clinical outcomes. RESULTS: HF (predominantly normal ejection fraction) was present in 50/163 (31%) patients with systemic hypertension and chronic kidney disease (serum creatinine >2 mg/ dL) undergoing PTRA for RAS and represented the major predictor of all-cause mortality in these patients. When compared with sex-matched RAS and HF patients treated medically, PTRA with stenting was associated with a significant decrease in the New York Heart Association Functional Class (1.9 +/- 0.8 versus 2.6 +/- 1.0, P < 0.04) and a 5-fold reduction in the number of hospitalizations. However, renal artery revascularization did not impact mortality. CONCLUSION: HF was present in one-third of patients with renal dysfunction and atherosclerotic RAS who were referred for PTRA. The presence of HF was associated with a significantly increased risk of death after PTRA with stenting. Renal artery revascularization resulted in improved HF control and a reduction in HF hospitalizations.

Peripheral vasculature: high-temporal- and high-spatial-resolution three-dimensional contrast-enhanced MR angiography.

PURPOSE: To prospectively evaluate the feasibility of performing high-spatial-resolution (1-mm isotropic) time-resolved three-dimensional (3D) contrast material-enhanced magnetic resonance (MR) angiography of the peripheral vasculature with Cartesian acquisition with projection-reconstruction-like sampling (CAPR) and eightfold accelerated two-dimensional (2D) sensitivity encoding (SENSE). MATERIALS AND METHODS: All studies were approved by the institutional review board and were HIPAA compliant; written informed consent was obtained from all participants. There were 13 volunteers (mean age, 41.9; range, 27-53 years). The CAPR sequence was adapted to provide 1-mm isotropic spatial resolution and a 5-second frame time. Use of different receiver coil element sizes for those placed on the anterior-to-posterior versus left-to-right sides of the field of view reduced signal-to-noise ratio loss due to acceleration. Results from eight volunteers were rated independently by two radiologists according to prominence of artifact, arterial to venous separation, vessel sharpness, continuity of arterial signal intensity in major arteries (anterior and posterior tibial, peroneal), demarcation of origin of major arteries, and overall diagnostic image quality. MR angiographic results in two patients with peripheral vascular disease were compared with their results at computed tomographic angiography. RESULTS: The sequence exhibited no image artifact adversely affecting diagnostic image quality. Temporal resolution was evaluated to be sufficient in all cases, even with known rapid arterial to venous transit. The vessels were graded to have excellent sharpness, continuity, and demarcation of the origins of the major arteries. Distal muscular branches and the communicating and perforating arteries were routinely seen. Excellent diagnostic quality rating was given for 15 (94%) of 16 evaluations. CONCLUSION: The feasibility of performing high-diagnostic-quality time-resolved 3D contrast-enhanced MR angiography of the peripheral vasculature by using CAPR and eightfold accelerated 2D SENSE has been demonstrated.

Management of a retrorectal lipomatous hemangiopericytoma by preoperative vascular embolization and a multidisciplinary surgical team: report of a case.

Large, highly vascular pelvic tumors can be challenging to manage, and bleeding is a major concern of the surgeon. Other concerns relate to the risk of injury to associated pelvic structures, difficulties in operative exposure, and complete tumor removal. We report an unusual case of a massive retrorectal lipomatous hemangiopericytoma managed successfully by preoperative vascular embolization and a multidisciplinary surgical team. The combined efforts of an interventional radiologist, vascular surgeon, orthophedic oncologist, and colorectal surgeon led to successful and safe complete removal of the tumor.

What are the keys to successful adrenal venous sampling (AVS) in patients with primary aldosteronism?

Adrenal venous sampling (AVS) is the criterion standard to distinguish between unilateral and bilateral adrenal disease in patients with primary aldosteronism. The keys to successful AVS include appropriate patient selection, careful patient preparation, focused technical expertise, defined protocol, and accurate data interpretation. The use of AVS should be based on patient preferences, patient age, clinical comorbidities, and the clinical probability of finding an aldosterone-producing adenoma. AVS is optimally performed in the fasting state in the morning. AVS is an intricate procedure because the right adrenal vein is small and may be difficult to locate - the success rate depends on the proficiency of the angiographer. The key factors that determine the successful catheterization of both adrenal veins are experience, dedication and repetition. With experience, and focusing the expertise to 1 or 2 radiologists at a referral centre, the AVS success rate can be as high as 96%. A centre-specific, written protocol is mandatory. The protocol should be developed by an interested group of endocrinologists, radiologists and laboratory personnel. Safeguards should be in place to prevent mislabelling of the blood tubes in the radiology suite and to prevent sample mix-up in the laboratory.

Renal artery stent placement for restoration of renal function in hemodialysis recipients with renal artery stenosis.

PURPOSE: Renal artery stent placement to treat renal artery stenosis (RAS) in patients undergoing hemodialysis is not performed commonly. We present our outcomes of discontinuation of hemodialysis after treating patients with RAS by stent placement on acute (< or =30 days of hemodialysis) and chronic hemodialysis (>30 days). MATERIALS AND METHODS: A retrospective study was conducted in 16 patients (nine men) with an average age of 74.6 years +/- 10.6 (range, 49-86 y) who underwent treatment of 22 RAS for acute renal failure (n = 8) or uncontrolled hypertension with chronic hemodialysis (n = 8). The average follow-up was 448 days +/- 450 (median, 363.5 d; range, 6-1,583 d). The primary outcome consisted of discontinuation of hemodialysis, death, and transplantation. Secondary endpoints included restenosis, changes in blood pressure (and use of medications), and estimated glomerular filtration rate (eGFR). RESULTS: After the stent procedure, eight patients were able to discontinue hemodialysis and remained free from dialysis over a mean period of 564 days +/- 533. The predictors of discontinuation of hemodialysis were 24-hour proteinuria, eGFR before renal artery stent placement, and size of the kidney on ultrasound studies (P < .05 for all three). There was no difference in patients who were undergoing acute versus chronic hemodialysis. There were three minor complications, and one patient died 6 days after the procedure because of multiple cardiovascular problems. CONCLUSIONS: Renal artery stent placement for the treatment of RAS in patients receiving hemodialysis can result in discontinuation of hemodialysis in patients with low proteinuria level and adequate kidney size and eGFR.

Comparison between gadolinium and iodine contrast for percutaneous intervention in atherosclerotic renal artery stenosis: clinical outcomes.

BACKGROUND: Percutaneous angiography with iodinated contrast in patients with chronic kidney disease carries a risk of contrast nephropathy, which is independently associated with renal disease progression and increased mortality. Gadolinium contrast is a potential alternative to iodinated contrast for percutaneous transluminal renal angioplasty (PTRA), and appears to be safe and well tolerated. The aim of this study was to assess the results of gadolinium use to facilitate PTRA in patients with chronic kidney disease. METHODS: Clinical outcomes were compared between patients with serum creatinine (Cr) >/= 176 micromol/L (2 mg/dL), who had either gadolinium (n = 57; gadoteridol or gadodiamide), iodinated (n = 68; iohexol or iodixanol) or a combination of gadolinium and iodinated-contrast-enhanced (n = 38) PTRA. RESULTS: Despite similar degrees of pre-procedural renal insufficiency, the incidence of immediate contrast nephropathy [defined as an increase in serum Cr of 44 micromol/L (0.5 mg/dL) within 7 days without other identifiable causes] was lowest in the gadolinium group (3/57, 5.3%) compared to those receiving a combination of modest iodinated contrast in addition to gadolinium (4/38, 10.5%) or solely iodinated contrast (14/68, 20.6%). This was associated with a reduction in the 30-day progression to need for renal replacement therapy (RRT) (P < 0.005). Yet, over a mean follow-up of 40 +/- 22 months, renal function outcomes or all-cause mortality were not different between the contrast groups. The type of contrast used had no effect on technical success and both short- and long-term blood pressure outcomes were comparable between the groups. Two patients developed pathology-proven nephrogenic fibrosing dermopathy, a serious skin condition that has been seen in patients with kidney disease following administration of gadolinium. CONCLUSIONS: Gadolinium contrast appears to be an effective agent for interventional renal angiograms. Compared to iodinated contrast, gadolinium contrast is associated with a significantly lower incidence of contrast nephropathy and early progression to end-stage renal disease (ESRD) in patients with pre-existing chronic kidney disease. The risk of fibrosing dermopathy however and remains to be established.

Abdominal findings in hereditary hemorrhagic telangiectasia: pictorial essay on 2D and 3D findings with isotropic multiphase CT.

The rapid evolution in multidetector computed tomographic (CT) technology has produced improvements in temporal and spatial resolution, leading to greater recognition of the spectrum of abdominal findings in hereditary hemorrhagic telangiectasia (HHT). In this multisystem vascular disorder, the abdominal findings are predominantly within the liver. Hepatic vascular lesions in HHT range from tiny telangiectases to transient perfusion abnormalities and large confluent vascular masses. Focal hepatic lesions are often associated with arteriovenous, arterioportal, or portovenous shunts. Pancreatic, splenic, and other vascular abnormalities are also observed because they are included in the field of view. By taking advantage of the increased z-axis spatial resolution and faster scanning times, and by using a bolus tracking technique, multiphase CT can be used to identify hepatic and extrahepatic lesions in HHT and to characterize the associated vascular shunts. Coronal maximum intensity projection images are particularly helpful in depiction of small hepatic vascular lesions.

The clinical conundrum of corticotropin-independent autonomous cortisol secretion in patients with bilateral adrenal masses.

BACKGROUND: Management of patients with bilateral adrenal masses and corticotropin (ACTH)-independent Cushing syndrome (CS) or subclinical CS is problematic. We report our experience with adrenal venous sampling (AVS) in the evaluation of 10 patients with bilateral masses who had ACTH-independent CS or subclinical CS. PATIENTS AND METHODS: Ten patients (9 women, 1 man, mean age 56.4 years) with bilateral adrenal masses and ACTH-independent CS (n=3) or subclinical CS (n=7) underwent AVS. Autonomous cortisol secretion was documented in all cases with suppressed serum ACTH concentrations and lack of cortisol suppression with dexamethasone administration. Adrenal venous sampling was performed on the second day of dexamethasone administration. Cortisol and epinephrine levels were measured from each adrenal vein (AV) and from a peripheral vein (PV). RESULTS: Mean (+/-SD) maximal diameter of the adrenal masses on computed tomography was 3.3+/-1.3 cm (range: 1.2-6.0 cm). Successful catheterization was confirmed with AV:PV epinephrine gradients. A cortisol AV:PV gradient>6.5 was consistent with a cortisol-secreting adenoma in 11 adrenal glands; 5 patients had clinically important bilateral autonomous cortisol hypersecretion, 3 had bilateral cortisol-secreting adenomas, and 2 had ACTH-independent macronodular adrenal hyperplasia. Adrenal venous sampling-guided adrenalectomy was completed in all 10 patients-2 patients had total bilateral adrenalectomy and 2 others had subtotal bilateral adrenalectomy. During a mean follow-up of 36.1 months (range: 0.7-123 months), CS or clinically important cortisol secretory autonomy did not recur. CONCLUSIONS: Adrenal venous sampling contributed to the localization of autonomous hypercortisolism in the setting of ACTH-independent CS or subclinical CS in patients with bilateral adrenal masses.

Restenosis following percutaneous renal artery revascularization.

BACKGROUND/AIMS: Restenosis following percutaneous transluminal renal angioplasty (PTRA) remains a concern even in the era of adjuvant stenting. The optimal form of therapy, and particularly the role of repeat PTRA in the treatment of recurrent hypertension associated with renal artery restenosis, is largely unknown. The aims of this study were to determine the risk factors for restenosis and to evaluate the blood pressure outcomes of patients who underwent repeat PTRA. METHODS: Clinical and procedural characteristics of 32 patients who developed recurrent hypertension and renal artery restenosis were compared to a control group of patients who maintained renal artery patency and adequate blood pressure control after the first procedure. The groups were matched for sex and initial procedure date. RESULTS: The restenosis group had a mean age of 71 +/- 12 years, a female/male ratio of 24/8, an average blood pressure of 179/87 mm Hg, despite three antihypertensive medications, and a serum creatinine level of 1.5 +/- 0.4 mg/dl. Repeat PTRA performed for clinically significant restenosis was 10.7 +/- 8 months after the first procedure, and 17 of the 32 patients had a measurable blood pressure benefit at last follow-up (177 +/- 119 weeks). The development of restenosis was positively associated with body weight (p = 0.003) and body mass index (p = 0.008), but independent of diabetes mellitus, hyperlipidemia, or statin therapy. Of the 15 patients who failed the second procedure, 4 went on to have third PTRA, none of whom had sustained benefit. CONCLUSIONS: An increased body mass index is associated with restenosis following initial PTRA. Patients with restenosis can be treated successfully with repeat PTRA which provides sustained improvement in blood pressure control in approximately half of these patients.

Embolization of a pulmonary arterial pseudoaneurysm with endovascular coils.

Unrecognized pseudoaneurysm or rupture of a pulmonary artery is a rare but potentially catastrophic complication of pulmonary arterial catheterization. Herein, we describe a teenage patient with a pulmonary arterial pseudoaneurysm, probably iatrogenic, who presented with haemoptysis following catheterization of the right heart. The pseudoaneurysm was successfully embolized using coils inserted by catheter. Increased awareness of this lesion, its rapid recognition, and prompt therapy are the keys to a successful outcome.

Vascular Ehlers-Danlos syndrome: imaging findings.

OBJECTIVE: Vascular Ehlers-Danlos syndrome (EDS), formerly known as EDS type IV, is an autosomal dominant disorder characterized by fragility of medium and large arteries due to type III procollagen deficiency. Our purpose was to review the imaging findings in a cohort of patients with a diagnosis of vascular EDS. MATERIALS AND METHODS: The radiologic, surgical, and genetic databases at a single multispecialty medical practice were reviewed for a 35-year period between 1971 and 2006. Thirty-three patients with a clinical diagnosis of vascular EDS were identified. Imaging studies were available for 28 patients, 13 men and 15 women, with a mean age of 39.8 +/- 16 years at the time of diagnosis. A vascular radiologist reviewed a total of 189 imaging examinations: 87 CT, 27 MRI, 59 sonography, and 16 angiography. RESULTS: Vascular abnormalities were present in 22 (78%) of 28 patients. Arterial abnormalities included 41 aneurysms, 19 dissections, 12 ectasias, and 10 occlusions. There was one splenic vein aneurysm and one carotid cavernous fistula. Six patients had a total of 10 parenchymal infarcts involving the brain (n = 5), kidney (n = 3), and spleen (n = 2). Nine patients had 10 hemorrhagic events, five related to spontaneous vascular rupture and five associated with interventional or surgical procedures. Six patients had 13 nonvascular findings. CONCLUSION: The most common findings were arterial aneurysms and dissections, followed by arterial ectasias and occlusions. Life-threatening complications included hemorrhage and infarcts.

Splanchnic artery aneurysms.

Autopsy studies suggest that splanchnic artery aneurysms may be more frequent than abdominal aortic aneurysms. These aneurysms are important to recognize because up to 25% may be complicated by rupture, and the mortality rate after rupture is between 25% and 70%. However, little is known about the natural history and clinical presentation of splanchnic artery aneurysms. Splenic artery aneurysms are the most common of the splanchnic artery aneurysms; multiple aneurysms are present in approximately one third of patients. Hepatic artery pseudoaneurysms are more common than true aneurysms because of increasing numbers of hepatobiliary interventional procedures. The diagnosis of splanchnic artery aneurysm should be considered in any patient with abdominal pain, a pulsatile mass, or an abdominal bruit with or without associated bleeding. However, most aneurysms are asymptomatic and are detected incidentally on imaging studies. Treatment, which can be either surgical or interventional radiology-based, should be considered in all patients with symptoms related to the aneurysms, if the aneurysm is more than 2 cm in diameter, if the patient is pregnant, or if there is demonstrated growth of the aneurysm.

Predictors of failure of endovascular therapy for peripheral arterial disease.

The objective of this study was to assess the usefulness of a comparison of clinical failure and restenosis rates of endovascular procedures at 1 year in patients with peripheral arterial disease. The resulting comparison is presented as "clinical failure/restenosis coordinate." The authors screened 171 papers describing the outcome of lower extremity angioplasty or stent placement. In 20 of them, authors reported detailed outcomes of interest, including baseline demographic measurements, location of arterial occlusive lesions, a measure of restenosis (measured by ankle-brachial indices, ultrasonography, or angiography), and clinical outcomes (mortality, repeat percutaneous transluminal angioplasty, or amputation). An overview of these 20 angioplasty papers was performed. Besides the usual meta-analyses of each end point separately, data were also plotted as coordinates of clinical failure versus restenosis. The clinical failure-to-restenosis coordinate was calculated and reported for percutaneous transluminal angioplasty of the aortoiliac and femoropopliteal distributions. Clinically reported outcomes in the literature were used to calculate the clinical failure/restenosis coordinate. This value was significantly different for various locations of the angioplasty and various baseline angiographic characteristics. A numeric coordinate pair of clinical failure and restenosis is identifiable in patients undergoing endovascular treatment of peripheral arterial disease. The varying coordinates may be important in elucidating the incidence and mechanisms of clinical failure after endovascular treatment. The coordinate reported in this article is hypothesis-generating about mechanisms of endovascular treatment failure. This coordinate is important in determining the role of restenosis in the clinical failure of endovascular therapy of peripheral arterial disease.

An investigation of operator exposure in interventional radiology.

A study was conducted to investigate how operator exposure in interventional radiology is affected by various common fluoroscopic imaging conditions. Stray radiation levels surrounding the imaging chain of a C-arm angiographic system were measured with an anthropomorphic abdomen phantom under different imaging conditions, and isodose curves were constructed. Operator exposure was shown to increase with patient dose-area product as the imaging field of view (FOV) is changed, with the highest scatter levels occurring with an intermediate-sized FOV. Use of copper spectral beam filtration was found to result in decreased operator exposure, whereas use of wedge-shaped equalization filters was found to increase exposure. The effect of increasing patient abdomen thickness was simulated by surrounding the phantom with plastic bolus material. Increasing the thickness by 5 cm resulted in a doubling of exposure at the operator's waist. Exposure to the operator's upper body was significantly reduced when the FOV was positioned on the far side of the patient. Operator exposure can be maintained at an acceptable level by taking these variables into consideration and incorporating the suggested dose reduction techniques into routine practice to the greatest extent possible.

Large congenital pelvic arteriovenous malformation and management options.

The congenital pelvic arteriovenous malformation (AVM) arises from dysplastic arteries and veins. These rare conditions might present to the urologist by producing massive hematuria. Most AVMs can be controlled by surgical resection, usually in conjunction with preoperative angiographic embolization. Here, we present a case of a large pelvic AVM that caused significant patient morbidity and required treatment by novel methods after the usual means had failed. In this report, we will detail those unique interventions required to control a tenuous clinical situation.

Intramuscular hemangioma of the foot: a diagnostic dilemma.

Intramuscular hemangioma is a rare but important cause of pain and potentially decreased performance in athletes. These benign tumors occur more often in the lower extremity and usually present during the first three decades of life. Symptomatic intramuscular hemangiomas usually present with pain and swelling, which often worsen with activity. Diagnosis can be difficult, resulting in frustration and prolonged activity limitations for these patients. Magnetic resonance imaging and clinical findings can often suggest the diagnosis. Recommended treatment is usually wide total excision, but there are certain cases in which excision is not possible. In difficult areas such as the hands or feet, a sclerosing agent can be injected into the hemangioma to reduce the size of the hemangioma, decrease pain, and improve function.