Off label use of devices and drugs in interventional radiology.

AIM: To establish how often off-label device and drug use occurs in interventional radiology (IR) in a UK tertiary referral hospital and consider the wider implications for the interventional radiologist. MATERIALS AND METHODS: Prospective data were collected during interventional procedures for 1 working week in a university hospital. Out-of-hours procedures and procedures outside the department were excluded. Operators were asked to record the drugs and devices used, the indication, and method of use. The instructions for use/summary of product characteristics were then studied for each device/drug used to assess if the use was on or off-label. RESULTS: During the study period 52 cases were performed and data were available on 26 cases (50%). In 22 of the 26 cases (84%) there was evidence of off-label use of devices or drugs. Off-label use of drugs included treatment of venous malformations with Fibrovein(©) (sodium tetradecyl sulphate), which is licensed for the treatment of varicose veins in the leg, and intra-arterial injection of heparin, which is licensed for intravenous and subcutaneous use. Off-label device use included placing vascular sheaths in the urinary tract, using angiographic catheters to guide wires in the urinary tract, using sheaths for thrombosuction, reshaping of the tip of most guidewires, and using angioplasty balloons to dislodge the arterial plug at fistula thrombectomy. CONCLUSION: Off-label device and drugs use is common in a UK tertiary hospital IR department and literature suggests this is common in the wider IR community. There are important clinical and legal implications for off-label use for patients and physicians.

TIPSS in the treatment of ectopic variceal bleeding.

BACKGROUND/AIMS: Bleeding from ectopic varices is a well recognized life-threatening complication of portal hypertension but the optimal treatment of this problem is yet to be established. METHODOLOGY: We retrospectively reviewed patients with ectopic variceal bleeding who underwent transjugular intrahepatic portosystemic shunting for recurrent bleeding not responding to conservative management. RESULTS: Over an eleven-year period we identified ten patients who underwent TIPSS for ectopic variceal hemorrhage. Six patients bled from rectal varices and four from stomal varices. TIPSS was successful in nine patients. The Childs-Pugh grade of the patients was A=3, B=3 and C=4. The follow-up period ranged from 7 days to 1380 days. Rebleeding occurred in three patients, two of whom died. The remaining patient had a blocked TIPSS and successfully underwent repeat stenting which re-established patency. Four patients (Childs B=2, Childs C=2) died within 60 days. All three patients with Childs A liver disease were alive at one year. CONCLUSIONS: TIPSS can be used effectively to treat ectopic variceal bleeding. Patients with Childs grade A liver disease appear to do well with TIPSS. Those with advanced liver disease (Childs B & C) have a uniformly poor outcome. In these patients ectopic variceal hemorrhage is likely to represent a terminal event.

Perianeurysmal fibrosis: a relative contra-indication to endovascular repair.

OBJECTIVE: Perianeurysmal fibrosis (PAF) with involvement of neighbouring viscera can render open repair of inflammatory aneurysms technically difficult and therefore hazardous. For this reason, endovascular repair (EVAR) has been advocated as the preferred approach for this condition. EVAR is known to induce a systemic inflammatory response in patients but the nature of the local response remains unknown. If significant, such a response could exacerbate rather than ameliorate PAF. The aim of the study was to examine the incidence, course and consequences of perianeurysmal fibrosis detected by computerised tomography (CT) before and after EVAR. MATERIAL AND METHODS: The clinical records of patients treated by EVAR and followed for at least 6 months were reviewed. Pre and post-operative CT images were independently graded for PAF by three radiologists according to a standard protocol. RESULTS: PAF was documented preoperatively in six out of a total of 61 patients. In two of these PAF worsened after EVAR resulting in ureteric obstruction and hydronephrosis requiring ureteric stents. In the remaining 4 patients PAF did not reduce postoperatively. PAF of low grade developed postoperatively in 10 out of 55 patients (18%) in whom there was no evidence of PAF on preoperative imaging. Median follow-up was 18 months (range 6-36 months). The development of periaortic fibrosis de novopostoperatively was statistically significant (McNemar's test p=0.002). CONCLUSION: EVAR does not seem to reverse PAF if this is present preoperatively and it induces this condition in approximately one sixth of patients without evidence of preoperative PAF. The potential for this adverse inflammatory local response should be taken into account when considering EVAR for treatment of aneurysms with perianeurysmal fibrosis and must be weighed against the perceived benefits of this approach.

Aortic side branch embolization before endovascular aneurysm repair: incidence of type II endoleak.

PURPOSE: To assess the feasibility of embolization of aortic side branches and its impact on the incidence of type II endoleak after endovascular aneurysm repair. MATERIALS AND METHODS: Endovascular aneurysm repair was performed in 74 patients. Aortic side branch vessels were evaluated on the preoperative angiogram and computed tomography (CT) and, where embolization of lumbar and inferior mesenteric vessels was considered technically possible, this was attempted prior to endovascular repair. Follow-up CT was used to assess the presence of type II endoleak. RESULTS: Seventy-two patients were followed up for longer than 1 month. Embolization was attempted in 25 cases, successfully in 10, with partial success in 11, and failure in four. Twenty patients with successful or partly successful preoperative embolization were discharged and followed-up. Four (20%) had demonstrable type II endoleak during follow-up, with two of these persisting at latest follow-up. Of 43 patients without previous embolization, there were 10 (23.3%) type II endoleaks during the follow-up period, four of these persisting. In cases with type II endoleak, mean sac diameter change was -0.5 mm in the cases with previous embolization and +3.1 mm without. The mean period to onset of type II endoleak was 6.9 months without, and 15.3 months with, previous embolization. CONCLUSION: Although the cohort size is below a level that would confer significance, the trend of these findings is such as to suggest a lack of influence of aortic side branch embolization on the incidence of type II endoleak during the follow-up period.

Graft distortion after endovascular repair of abdominal aortic aneurysm: association with sac morphology and mid-term complications.

PURPOSE: To investigate the incidence, significance, and mechanism of stent-graft distortion after endovascular repair (EVR) of abdominal aortic aneurysm. METHODS: EVR of abdominal aortic aneurysm was performed in 51 cases (49 modular, bifurcated; 2 tube). Thirty-two patients were followed for 6 or more months and had equivalent baseline and follow-up images which could be used to determine changes in graft configuration. Sac dimensions were measured using computed tomographic (CT) images and graft-related complications were recorded. RESULTS: Amongst 32 patients evaluated on follow-up, there was graft distortion in 24. Distorted grafts were significantly (p = 0.002) associated with sac diameter reduction (mean 5 mm) and sac length reduction (mean 8.1 mm). All graft-related complications occurred in the limbs of eight distorted grafts, with a mean reduction of sac length in this group of 7.8 mm on reformatted CT images. CONCLUSION: There was a highly significant association between graft distortion and limb complications, and reduced sac dimensions.

Use of contrast-enhanced ultrasound in follow-up after endovascular aortic aneurysm repair.

PURPOSE: To investigate the use of contrast-enhanced ultrasound in the detection of endoleak after endovascular repair of abdominal aortic aneurysm. MATERIALS AND METHODS: Eighteen patients underwent follow-up on 20 occasions after endovascular aortic aneurysm repair by arterial-phase contrast-enhanced spiral computed tomography (CT). All patients had unenhanced color Doppler ultrasound and Levovist-enhanced ultrasound on the same day. The ultrasound examinations were reported in a manner that was blind to the CT results. CT was regarded as the gold standard for the purposes of the study. RESULTS: There were three endoleaks shown by CT. Unenhanced ultrasound detected only one endoleak (sensitivity, 33%). Levovist-enhanced ultrasound detected all three endoleaks (sensitivity, 100%). Levovist-enhanced ultrasound indicated an additional six endoleaks that were not confirmed by CT (specificity, 67%; positive predictive value, 33%). In one of these six cases, the aneurysm increased in size, which indicates a likelihood of endoleak. Two of the remaining false-positive results occurred in patients known to have a distal implantation leak at completion angiography. CONCLUSION: In this small group of patients, contrast-enhanced ultrasound appears to be a reliable screening test for endoleak. The false-positive results with enhanced ultrasound may be due to the failure of CT to detect slow flow collateral pathways. Although the number of patients in this study is small, enhanced ultrasound may be more reliable than CT in detecting endoleak.

An ultrastructural histochemistry and light microscopy study of the early development of renal proximal tubular vacuolation after a single administration of the contrast enhancement medium "Iotrolan".

The time course of contrast media (CM)-induced renal proximal tubular vacuolation was investigated in rats by light microscopy, transmission electron microscopy (TEM), and ultrastructural histochemistry for acid phosphate activity. Young adult male rats were treated with a single dose of 3.0 g I/kg Iotrolan (Isovist 300 mg I/ml) and sacrificed at 0 min, 5-min, 15-min, 15-min, 2-hr, and 24-hr intervals. Light microscopy of vibratome sections of freshly excised tissue of cryostat and paraffin sections was also performed to allow comparison of the appearance of the vacuoles in the fresh state with light and electron microscopy. The sequence of events seen to occur can be summarized as follows. CM-induced vacuolation occurred at a low level a soon as 5 min after compound administration. The vacuolation was observed by TEM but could not be detected by light microscopy. This was followed by an increase in size and numbers of vacuoles up to the 24-hr timepoint with a sequential increase in the staining for acid phosphatase activity of the vacuoles, most marked at the 24-hr timepoint. At timepoints less than 24 hr there appeared to be no marked increased in the normal complement by lysosomes or in the components of the Golgi-endoplasmic reticulum-lysosome pathway. At 24 hr, the vast majority, but not all, of the CM-induced vacuoles were positive for acid phosphatase activity. The intensity of staining varied, and there was evidence of infusion of small lysosomes with CM-induced vacuoles. These results suggest that formation of CM-induced vacuoles is a 2-stage process, following a normal pathway for the handling of endogenous and exogenous substances.

Stents in the biliary tree.

Biliary stenting has become established as a valuable method of palliation in malignant biliary strictures. The development of percutaneous and endoscopic techniques is described and illustrative cases are shown. The role of percutaneous vs endoscopic procedures is examined.

Barium meals in the elderly--a quality reassurance.

The consecutive double contrast barium meal examinations of 100 elderly patients (aged over 65 years) and a group of 33 younger adult patients were analysed by two observers for technical quality and pathological abnormalities. Technical quality declined with patient age, especially in those over 75 years, but was sufficient to enable diagnosis of abnormalities in 60% of the elderly group. It is concluded that, in the majority of elderly patients, the technical quality of double contrast barium meal examinations is sufficiently high to offer considerable diagnostic utility.

Clinical Utility of cranial CT in HIV positive and AIDS patients with neurological disease.

An analysis was made of the clinical, pathological and radiological data relating to 117 requests for cranial CT on 83 patients who were HIV positive or had AIDS in one year at St Mary's Hospital. Central to the design was grouping of the patients according to clinical presentation. The aim was to establish whether there was evidence to support the view that, because of their immunocompromised state, these patients may commonly harbour serious, potentially treatable intracranial disease without the usual overt clinical signs. No patient who was only HIV antibody positive had treatable intracranial disease without focal neurological signs. In patients with AIDS, treatable or potentially treatable lesions were mainly confined to those with objective neurological signs or seizures. There is little evidence in this data to support the original hypothesis. While it would be inappropriate to advise that CT should never be carried out in the absence of focal signs or seizures, the results of this study should be useful in ascribing an appropriate degree of urgency to requests for cranial CT in these patients.

Outpatient myelography: an acceptable and cost-effective technique.

Sixty-five patients with stable low back pain had their lumbar myelography performed as outpatients, staying in the department for 1 h after the examination. The incidence of post-myelogram headache was similar to that reported for inpatients. No serious after-effects occurred in the study group. The vast majority of patients preferred to be at home following the study. It is concluded that outpatient myelography is safe, less expensive and preferred by the patients.