How safe is internal iliac artery embolisation prior to EVAR? A 10-year retrospective review.

PURPOSE: Internal iliac artery (IIA) embolisation is commonly performed prior to endovascular aneurysm repair (EVAR) of aortoiliac aneurysms to prevent type 2 endoleaks via the internal iliac arteries. The safety of this procedure is controversial due to the high incidence of pelvic ischaemic complications. METHODS: We undertook a retrospective review of all patients undergoing IIA embolisation before EVAR from 2002 to 2012, to determine incidence of, and factors associated with pelvic ischaemia. RESULTS: Eight of 25 patients (32 %) experienced new-onset ischaemia, including erectile dysfunction (4 %), and buttock claudication (28 %) that persisted >6 months in only four patients (16 %). Both bilateral IIA embolisation and a shorter time interval to EVAR correlate with increased risk (p = 0.006 and p = 0.044). No co-morbidities or demographic factors were predictive. CONCLUSIONS: We conclude that IIA embolisation remains a beneficial procedure, however, to minimise the risk of buttock claudication we advise against both bilateral IIA embolisation and short time intervals between embolisation and subsequent EVAR.

Transcatheter embolisation of renal angiomyolipoma.

INTRODUCTION: Angiomyolipomas (AML) are rare benign renal tumours which are associated with aneurysms that can cause haemorrhage. Embolisation of AML greater than 4 cm with a variety of embolic agents is now the first-line treatment in these cases. METHODS: This was a retrospective analysis of all patients who underwent AML embolisation at Beaumont Hospital from 2000 to 2006 to review the efficacy of embolisation in the treatment of AMLs. RESULTS: There were six patients in total (n = 6). One patient (16%) had a background of tuberous sclerosis. Half of the patients presented acutely with bleeding and abdominal pain (50%) while the other half were found incidentally. There were no mortalities overall and three patients (50%) developed post embolisation syndrome. Five patients (83%) had a good response to embolisation with no further growth or regression of the AML. CONCLUSION: Embolisation is a safe and effective method for treating patients with AML.

Emergency percutaneous transcatheter embolisation of acute arterial haemorrhage.

AIMS: The purpose of this study was to review indications, source of haemorrhage, method of embolisation and clinical outcome in patients referred to Interventional Radiology for the emergency management of acute arterial haemorrhage. METHODS: Retrospective review of patients undergoing emergency percutaneous embolisation over 4 years. Clinical details, computed tomographic findings, embolisation procedure details and clinical outcome are outlined. RESULTS: Patients (n = 41) were included with various clinical indications for embolisation [haemoptysis (n = 8), iatrogenic (n = 7), traumatic pseudoaneurysm (n = 3), retroperitoneal bleed (n = 3), GI bleed (n = 6), splenic rupture (n = 1), renal laceration (n = 1), epistaxis (n = 12)]. Embolisation material consisted of coils, embospheres, glue, and covered stents. Technical success was achieved in 100% of cases. One patient died 2 days after embolisation secondary to myocardial infarction. CONCLUSION: Emergency arterial embolisation is a potentially life-saving treatment. Although it is technically challenging, indications are becoming increasingly varied and outcomes are more successful because of the availability of microcatheters and effective embolisation materials.

Interventional radiology in the diagnosis, management, and follow-up of pseudoaneurysms.

Arterial wall disruption, as a consequence of inflammation/infection, trauma (penetrating or blunt), or iatrogenic causes, may result in pseudoaneurysm formation. Currently, iatrogenic causes are increasing as a result of the growth of endovascular intervention. The frequency of other causes also seems to be increasing, but this may simply be the result of increased diagnosis by better imaging techniques, such as multidetector contrast-enhanced computed tomography. Clinically, pseudoaneurysms may be silent, may present with local or systemic signs, or can rupture with catastrophic consequences. Open surgical repair, previously the mainstay of treatment, has largely been replaced by image-guided occlusion methods. On the basis of an experience of over 100 pseudoaneurysms, treatments at various anatomical sites, imaging modalities used for accurate diagnosis, current changing therapeutic options for pseudoaneurysm management, approved embolization agents, and clinical follow-up requirements to ensure adequate treatment will be discussed. Image-guided direct percutaneous and endovascular embolization of pseudoaneurysms are established treatment options with favorable success rates and minimal morbidity. The pendulum has now swung from invasive surgical repair of pseudoaneurysms to that of image-guided interventional radiology.

Do AshSplit haemodialysis catheters provide better flow rates in the long term?

BACKGROUND: Recently, interventional radiologists have adopted an increasingly prominent role in the placement and management of hemodialysis catheters, as well as in the research and development of new and better catheters. The purpose of this study was to evaluate the viability and hemodialysis efficiency of the AshSplit catheter and the Permcath catheter. METHODS: 204 consecutive patients requiring radiological insertion of hemodialysis catheters were followed, retrospectively, over a 42-month period. Both hemodialysis catheters were placed using a combination of ultrasonic and fluoroscopic guidance and tunneled appropriately. Information collected included catheter insertion sites, insertion complications, catheter duration, and final outcome. RESULTS: Over the study period of two years, 269 catheters were placed into 204 patients with end stage renal failure. Patients received either an AshSplit (101 patients, 127 catheters) or a Permcath (103 patients, 142 catheters). Vascular access route of choice was the right internal jugular vein (67% AshSplit, 71% Permcath). Insertion complications occurred in 18 patients overall (6.6%), with only 1 requiring further intervention (hemopneumothorax). Flow rates averaged 259 mls/min for AshSplits and 248 mls/min for Permcaths (p < 0.001). Follow-up of catheter viability for 42 months yielded a mean AshSplit catheter duration of 246 days (range 6-932) and 239 days (range 1-1,278) for Permcath (p = 0.46). Reasons for catheter failure and elective catheter removal were similar in both groups; however, Permcaths required significantly more thrombolysis than AshSplits, p < 0.001. CONCLUSION: The AshSplit provides significantly better flow rates and less thrombolysis compared to the Permcath, with similar catheter dwell times.

Ultrasound-guided endocavitary drainage of pelvic abscesses: technique, results and complications.

AIM: To evaluate the experience in our institution with ultrasound-guided transrectal and transvaginal (endocavitary) drainage of pelvic abscesses. MATERIALS AND METHODS: Eighteen patients (four male, 14 female; mean age 55 years, range 30-78 years) presenting with pelvic abscesses were referred to our institution for therapeutic drainage over a 4 year period. Patients received broad-spectrum antibiotics prior to drainage, which was performed by either the transvaginal or transrectal route under ultrasound guidance. Patients were given sedo-analgesia in the form of midazolam and fentanyl and local anaesthesia was also employed. Eight French catheters were inserted into the abscess cavities, and patients were subsequently monitored on a daily basis by a member of the interventional radiology team until such time as it was deemed appropriate to remove the catheter. RESULTS: Eighteen catheters were placed in 17 patients, and transvaginal aspiration alone was performed in one patient. Drainage was successful in 16 of 17 patients, but a transgluteal approach was ultimately required in the remaining patient to enable passage of a larger catheter into an infected haematoma. The mean duration of drainage was 5 days, mean time to defervesce 2 days. Spontaneous catheter dislodgement occurred in four patients associated with straining, but this did not have any adverse effect in three of the four patients. CONCLUSION: Endocavitary drainage is an effective method of treatment for pelvic abscesses. Spontaneous catheter dislodgement does not affect patient outcome.

Percutaneous radiologic gastrostomy with and without T-fastener gastropexy: a randomized comparison study.

PURPOSE: T-fastener gastropexy is used by many interventional radiologists during percutaneous radiologic gastrostomy (PRG) placement. Whether gastropexy is a prerequisite to safe gastrostomy placement is uncertain. We evaluated the use of T-fastener gastropexy versus no gastropexy for PRG in a prospective, randomized study. METHODS: Of 90 consecutive patients referred for PRG, 48 were randomly selected to receive T-fastener gastropexy (M:F, 35:13; mean age 62 years, range 20-90 years) and 42 to receive no gastropexy (M:F, 31:11; mean age 63 years, range 40-90 years). Technical difficulties and fluoroscopy times were recorded for both groups and all patients were followed up for postprocedural complications. T-fasteners were removed between 3 and 7 days after gastrostomy insertion. RESULTS: A major complication was encountered in four patients from the non-gastropexy group (10%). In these cases the guidewire and dilator "flipped" out of the stomach into the peritoneal cavity. This resulted in misplacement of the gastrostomy tube in the peritoneal cavity in two of the patients. This was discovered at the end of the procedure when a test injection of contrast medium was performed. In three of these patients the procedure was rescued and completed radiologically. One patient underwent endoscopic gastrostomy placement. Five of 48 patients (10%) who received a gastropexy had pain associated with the T-fastener sites. Six patients (13%) had skin excoriation at the T-fastener sites. No skin complications were seen in the non-gastropexy group. No statistical difference in fluoroscopy time was observed between the two groups. CONCLUSION: Our experience of PRG without T-fastener gastropexy involved a 10% incidence of serious technical complications. We suggest that T-fastener gastropexy should be performed routinely for all PRG procedures. T-fastener gastropexy has an associated minor complication of pain and skin excoriation at the gastrostomy site which resolves on removing the T-fasteners.

Percutaneous gastrostomy in patients who fail or are unsuitable for endoscopic gastrostomy.

PURPOSE: Percutaneous endoscopic gastrostomy (PEG) is not possible or fails in some patients. We aimed to categorize the reasons for PEG failure, to study the success of percutaneous radiologic gastrostomy (PRG) in these patients, and to highlight the associated technical difficulties and complications. METHODS: Forty-two patients (28 men, 14 women; mean age 60 years, range 18-93 years) in whom PEG failed or was not possible, underwent PRG. PEG failure or unsuitability was due to upper gastrointestinal tract obstruction or other pathology precluding PEG in 15 of the 42 patients, suboptimal transillumination in 22 of 42 patients, and advanced cardiorespiratory decompensation precluding endoscopy in five of 42 patients. T-fastener gastropexy was used in all patients and 14-18 Fr catheters were inserted. RESULTS: PRG was successful in 41 of 42 patients (98%). CT guidance was required in four patients with altered upper gastrointestinal anatomy. PRG failed in one patient despite CT guidance. In the 16 patients with high subcostal stomachs who failed PEG because of inadequate transillumination, intercostal tube placement was required in three and cephalad angulation under the costal margin in six patients. Major complications included inadvertent placement of the tube in the peritoneal cavity. There was one case of hemorrhage at the gastrostomy site requiring transfusion and one case of superficial gastrostomy site infection requiring tube removal. Minor complications included superficial wound infection in six patients, successfully treated with routine wound toilette. CONCLUSION: We conclude that PRG is a safe, well-tolerated and successful method of gastrostomy and gastrojejunostomy insertion in the technically difficult group of patients who have undergone an unsuccessful PEG. In many such cases optimal clinical evaluation will suggest primary referral for PRG as the preferred option.

Evaluation of the role of magnetic resonance myelography in lumbar spine imaging.

The purpose of our study was to evaluate the accuracy of MR myelography in depicting disc herniation in the lumbar spine when compared with conventional MRI in patients presenting with clinical evidence of disc herniation. One hundred patients referred for conventional MR imaging of the lumbar spine also had coronal MR (TR 9000 ms, TE 272 ms eff, NEX 3, echo train length 32) myelography performed. Three experienced observers compared magnetic resonance myelography (MRM) with conventional lumbar spine MR using the following variables: visibility of thecal sac and nerve roots, and the presence, location and severity of disc herniation. Disc protrusions were seen at 110 disc space levels on conventional MR images as opposed to 93 on MRM. However, only 72 % of lesions seen on conventional MR were diagnosed by MRM. Similarly, only 63.8 % of nerve root compression abnormalities seen at conventional MR were visualized when compared with conventional MRM. The sensitivity, specificity and accuracy of MRM when compared with conventional MR was 72, 93 and 85 %, respectively. The MRM technique yields images that resemble conventional myelography and may be used to help confirm abnormalities seen on conventional MR in selected cases; however, the large number of false-positive and false-negative examinations indicates that caution should be used in interpreting MRM images.

A comparison of compression ultrasound with color Doppler ultrasound for the diagnosis of symptomless postoperative deep vein thrombosis.

BACKGROUND: Despite advances in primary prophylaxis, venous thromboembolism still occurs in a considerable number of high-risk surgical patients. Screening with conventional ultrasound imaging to detect asymptomatic deep vein thrombosis (DVT) has been suggested as a strategy to improve management of such patients, but it is insufficiently sensitive. We evaluated the ability of color Doppler ultrasound to improve the sensitivity of compression ultrasound in the detection of asymptomatic DVT in high-risk orthopedic patients. METHODS: We prospectively evaluated bilateral compression and color Doppler ultrasound measurements of the entire leg in 204 consecutive patients who underwent elective hip or knee replacement surgery, using contrast venography as the reference test. The sensitivity, specificity, and positive predictive value of the ultrasonography tests were determined. RESULTS: The sensitivity, specificity, and positive predictive value (with 95% confidence intervals [CIs]) of compression ultrasound for the detection of proximal DVT were 60% (39%-81%), 96% (92%-99%), and 71% (48%-89%) respectively. The sensitivity, specificity, and positive predictive value (with 95% CIs) of compression ultrasound for the detection of calf vein thrombosis were 33% (18%-52%), 91% (83%-96%), and 58% (34%-80%), respectively. Color Doppler ultrasonography did not identify any additional proximal or calf vein thrombi to those detected by compression ultrasound alone. The sensitivity for all thrombi was 47% (95% CI, 34%-61%) with a positive predictive value of 65% (95% CI, 48%-79%). CONCLUSIONS: Color Doppler ultrasonography has a moderate to low accuracy for the detection of DVT in patients who have had hip and knee replacement surgery. Color Doppler ultrasonography does not increase the detection rate for asymptomatic DVT over compression ultrasound and thus cannot be recommended as a screening test in this setting.

Fibrin sealant in interventional radiology: a preliminary evaluation.

Tisseel, a fibrin sealant not approved for use in the United States, was tested in abdominal fistulas and sinuses (13 patients) and interventional biliary procedures (11 patients). The two components of Tisseel were introduced via a double-lumen catheter and formed a fibrin gel at the point of contact. Tracts were sealed permanently in seven fistulas and sinuses and in all 11 biliary cases.

Hepatic interstitial laser photocoagulation. An investigation of the relationship between acute thermal lesions and their sonographic images.

OBJECTIVES: The relationship between hepatic interstitial laser photocoagulation (ILP) lesions and their acute ultrasound images was evaluated. In addition, the natural history of ILP lesions in normal pig liver was documented. METHODS: Eighteen pigs underwent laparotomy and ultrasound-monitored ILP. In part 1 of the study, 12 pigs each had four separate exposures (1.50 W for 60, 100, 300, and 500 seconds) and were divided into four groups according to when they were killed (0, 3, 7, and 21 days). In part 2 of the study, six pigs each had two sequential exposures (1.60 W for 1,000 and then 500 seconds) at separate hepatic sites. Survival time was 3 days. Necropsy and histologic examination were performed in all animals. In 0- and 3-day survivors, actual thermal lesions were compared with "early" (immediately after ILP) and "late" (1 hour after ILP) ultrasound images. RESULTS: In the 300-, 500-, and 1,000-second exposures of parts 1 and 2, thermal lesions were overestimated or approximated by early ultrasound and were underestimated or approximated by late ultrasound. Analysis of variance showed statistically significant differences between thermal lesions and their early and late ultrasound images (F = 18.6, P < .001, no interactions). Time-growth characteristics of ILP lesions were reasonably consistent on ultrasound; exceptions were identifiable 200 seconds into the exposure. In part 2, ultrasound changes were minimal in five of six 500-second (second sequential) technically satisfactory exposures. Thermal lesions were seen at necropsy. All lesions healed by formation of granulation tissue and collagen. CONCLUSIONS: During ILP, early ultrasound images frequently overestimate actual thermal lesions. Ultrasound-monitored ILP of tumors may be most effective if, on early ultrasound, echogenic changes extend beyond the tumor margins. Late ultrasound images underestimate or approximate thermal lesions. Their value in clinical ILP should be investigated. It is unclear why ultrasound images of proven thermal lesions were not seen during 5 of 6 otherwise satisfactory 500-second ILP exposures performed immediately after 1,000-second exposures.

Perforated jejunal diverticulosis: radiologic diagnosis.

Jejunoileal diverticulosis, which is usually asymptomatic, is commonly found at autopsy or during small-bowel barium examination. Perforation of diverticula can cause generalized or localized intra-abdominal inflammatory disease, depending to some extent on the site of the perforation. The authors describe a patient with perforation of a jejunal diverticulum; the condition mimicked colonic inflammatory disease clinically and ultrasonographically. The correct diagnosis was made on the basis of the findings of cross-sectional imaging and barium examination.

Focal nodular hyperplasia of the liver--an imaging conundrum.

Focal nodular hyperplasia is a common benign tumour of the liver that usually does not require treatment. This tumour can be difficult to distinguish noninvasively from other lesions in young patients that may require intervention, such as hepatic adenoma and fibrolamellar carcinoma. The authors report three cases of histologically proven focal nodular hyperplasia and one case in which the imaging features strongly suggested this tumour. These cases illustrate many of the variable imaging features of focal nodular hyperplasia. The authors review the typical imaging findings for focal nodular hyperplasia, hepatic adenoma and fibrolamellar carcinoma, indicate the areas of overlap that make noninvasive diagnosis impossible and discuss the role of percutaneous biopsy in establishing the definitive diagnosis.

High-resolution ultrasound in assessment of the gastrointestinal tract.

Ultrasound (US) is frequently the first investigation performed in patients presenting with a variety of abdominal symptoms, and there is a growing appreciation of its value in a wide range of gastrointestinal (GI) disorders. The advantages of US are that it is quick, safe, readily available, noninvasive, and avoids ionizing radiation. It is now the primary imaging investigation when conditions such as appendicitis and hypertrophic pyloric stenosis (HPS) are suspected. For the diligent examiner careful assessment of the bowel can be rewarding either by diagnosing bowel pathology or identifying possible pathology and determining the most appropriate sequence of diagnostic investigations. Its real time capabilities are of particular usefulness in abdominal conditions; clinical correlation is instant and features such as peristalsis and bowel compressibility can be readily assessed. This review describes and illustrates the current role of high-resolution transabdominal US in the detection of GI pathology with discussion on some of the applications of endoscopic ultrasound (EUS) as they relate to this topic.

Pneumatic reduction of intussusception using carbon dioxide.

Pneumatic reduction using air has recently become popular for the initial non-surgical management of intussusception. Since carbon dioxide (CO2) is rapidly absorbed from body surfaces, it should theoretically result in less cramping and distension following reduction. We reviewed our recent experience with the pneumatic reduction of intussusception using CO2 in 26 children. In 22 of these the intussusception was reduced (85%). There was one performation with CO2; the patient did not suffer any postoperative complications. Five additional children who had been treated unsuccessfully with barium had intussusception subsequently reduced with CO2. Following CO2 reduction, most children were fed within hours, and there were no instances of significant abdominal distension or cramping. We conclude that pneumatic reduction of intussusception using CO2 is safe and effective, and has the theoretical advantage of more rapid absorption from the gastrointestinal tract than air.

Prenatal compensatory renal growth: documentation with US.

PURPOSE: To determine whether compensatory renal growth (CRG), which occurs in adults, children, and infants after loss of functioning renal tissue, occurs in fetal life. MATERIALS AND METHODS: Prenatal ultrasound scans were used to select 29 patients with a unilateral multicystic dysplastic kidney and four patients with unilateral renal agenesis. Accurate measurements of prenatal renal length were obtained in 21 of these patients; an accurate measurement of postnatal renal length and birth weight was obtained in 27 of these patients. Prenatal and postnatal renal measurements of the contralateral kidney were compared with renal length in 23 matched control patients and previously reported normal renal lengths. RESULTS: The single functioning kidneys in the study patients were significantly longer than those in the control patients before and after birth (P = .001). CONCLUSION: This study provides strong evidence to support the belief that CRG occurs before birth.