Search PubMed⌕ Search

Biomedical subjects

J Lammer

Publications and source records attributed to J Lammer.

173 records · Page 10Linked to original sources
PubMedDate not supplied

Embolization of iatrogenic vascular injuries of renal transplants: immediate and follow-up results.

PURPOSE: To evaluate the outcome in seven patients in whom iatrogenic vascular complications were treated with catheter embolization. METHODS: Angiography showed an arteriovenous fistula in six of the seven patients, a pseudoaneurysm in three patients, and an arteriocaliceal fistula in three patients. Embolization was performed with GAW coils or microcoils in all cases. In three patients enbucrilate, polyvinyl alcohol, or absorbable gelatin powder was administered as an adjunct to the coils. RESULTS: Angiographic success with total occlusion of the vascular injury was achieved in five of the seven patients and clinical success was achieved in four of seven cases. In two cases, nephrectomy after embolization was necessary because of renal artery occlusion or acute hemorrhage at the renal artery anastomosis, respectively. Infarction of 30%-50% of the renal parenchyma was seen in two cases. CONCLUSION: Angiographically successful embolization is not necessarily associated with clinical success. The complication rate is high.

Adult↗
PubMedDate not supplied

Spiral CT during selective accessory renal artery angiography: assessment of vascular territory before aortic stent-grafting.

We evaluated the vascular territory of accessory renal arteries in cases where the vessel might be overlapped by an aortic stent-graft. Spiral CT during selective accessory renal artery angiography was performed in four patients with abdominal aortic aneurysms (including one with a horseshoe kidney). The volume of the vascular territory of each renal artery was measured using a software program provided by the CT unit manufacturer. The supernumerary renal arteries perfused 32%, 37%, 15%, and 16% of the total renal mass, respectively. In two patients, stent-grafts were implanted, which resulted in occlusion of the supernumerary renal artery. The volume of the renal infarction was equal to the volume perfused by the artery as calculated before implantation of the stent-graft. The method proposed is accurate for estimating the size of the expected renal infarction. It might help to determine whether placement of a stent-graft is acceptable.

Aorta, Abdominal↗
PubMedDate not supplied

Arterial hepatic embolization of unresectable hepatocellular carcinoma using a cyanoacrylate/lipiodol mixture.

PURPOSE: A survival analysis in 16 patients with unresectable hepatocellular carcinoma (HCC) undergoing transcatheter arterial embolization (TAE) using a combination of lipiodol and N-butyl-2-cyanoacrylate (5:1) was performed in a retrospective study. METHODS: A combination of lipiodol and N-butyl-2-cyanoacrylate (5:1) was used for TAE. All patients had disease compatible with Okuda stages I and II. RESULTS: Twenty-four embolizations were done; five patients had more than one embolization. Median alpha-fetoprotein levels declined from 116 to 48.6 ng/ml. A median of 0.3 ml cyanoacrylate was administered per patient. Median survival was 8.5 months (range 2-49 months). After a median follow-up of 4 years, 12 patients have died (75%). Okuda stage I and II patients had a median survival time of 34.4 and 5.5 months respectively. Few side effects (19%) were seen. CONCLUSION: We conclude that the TAE procedure used [lipiodol and N-butyl-2-cyanoacrylate (5:1)] is safe and produced only few side effects, thus constituting a valuable therapeutic option for patients with Okuda stage I and II HCC.

Aged↗
PubMedDate not supplied

Primary implantation of polyester-covered stent-grafts for transjugular intrahepatic portosystemic stent shunts (TIPSS): A pilot study.

PURPOSE: To investigate whether placement of a polyester-covered stent-graft increases the primary patency of transjugular intrahepatic portosystemic stent shunts (TIPSS). METHODS: Between 1995 and 1997 Cragg Endopro or Passager MIBS stent-grafts were used for the creation of TIPSS in eight male patients, 35-59 years of age (mean 48 years). All patients suffered from recurrent variceal bleeding and/or refractory ascites due to liver cirrhosis. Seven stent-grafts were dilated to a diameter of 10 mm, one to 12 mm. Follow-up was performed with duplex ultrasound, clinical assessment, and angiography. RESULTS: The technical success rate for creation of a TIPSS was 100%. The mean portosystemic pressure gradient decreased from 25 mmHg to 12 mmHg. In seven of eight patients TIPSS dysfunction occurred between 2 days and 3 years after stent-graft placement. In one patient the TIPSS is still primarily patent (224 days after creation). The secondary patency rates are 31 days to 3 years. CONCLUSION: The primary use of polyester-covered stent-grafts for TIPSS did not increase primary patency rates in our small series.

Adult↗
PubMedDate not supplied

MR-imaging with Gd-DTPA in carcinomas of tongue, oro- and hypopharynx.

High-field MRI was performed in a series of 24 patients with squamous cell carcinomas of the tongue, oro- and hypopharynx. The value of contrast enhanced T1-weighted images in tumor staging was established prospectively. Non-contrast T1-weighted images did not provide sufficient tumor-delineation. Marked contrast enhancement produced by Gd-DTPA was observed in all carcinomas and in normal pharyngeal mucosa. In tumors of the tongue and upper pharynx clinical examination and ultrasound were equally sensitive as post-contrast MRI; in tumors of the lower pharynx the true tumor extension could be better assessed by contrast-enhanced MRI.

Adult↗
PubMedDate not supplied

Intraluminal 192Ir brachytherapy following transjugular intrahepatic portosystemic shunt revision: long-term results and radiotherapy parameters.

PURPOSE: The stenosis or occlusion of transjugular intrahepatic portosystemic shunt (TIPS) occurs in up to 75% of patients within 12 months after treatment. The aim of our investigation was to evaluate the feasibility, safety and efficacy of intraluminal high-dose rate brachytherapy (HDRBT) with Iridium-192 following TIPS revision to prevent restenosis due to pseudointimal hyperplasia. MATERIALS AND METHODS: Between September and November 1996, intraluminal BT was performed in five patients after TIPS revision. The indications for initial TIPS were a Budd-Chiari syndrome in two female patients and recurrent variceal bleeding by alcoholic liver cirrhosis in three male patients. TIPS was created with Wallstents (10 mm diameter in four patients) and Palmaz stent (10 mm diameter in one patient). The re-dilatation was done in all five patients 6 months after first stenting because of restenosis (>50% stent lumen reduction) or occlusion of the stent. A 5-French closed-tip, noncentered BT delivery catheter was used for subsequent radiotherapy. The whole length of the stent and performed dilatation (interventional length - IL) was taken as clinical target length (CTL). A 10-mm safety margin was added proximal and distal to the CTL due to uncertainties of BT source positioning, so forming the planning target length (PTL). To ensure that prescribed dose covers the whole PTL, the active source length (ASL) was 5 mm longer proximal and distal than PTL, so forming the reference isodose length (RIL). A dose of 12 Gy was prescribed in 3 mm distance from the source axis in the mid-plane of the applicator for three patients and in 5 mm distance for two patients. RESULTS: A normal patency (<50% lumen reduction) of the stent was achieved at 44 months follow-up (duplex sonography+portography) in all three patients with liver cirrhosis, whereas further revisions were necessary in two patients with Budd-Chiari syndrome (after 5.5 and 18 months). No acute, subacute or late brachytherapy (BT)-related side effects were seen until now. CONCLUSIONS: HDRBT following TIPS revision was safe and feasible in all patients. The exact impact of BT on the TIPS patency should be evaluated in larger clinical trials. Moderate dose escalation and use of today's commercially available centering radiation catheters seem to be necessary.

Adult↗
PubMedDate not supplied

Spiral CT angiography in the assessment of abdominal aortic aneurysms after stent grafting: value of maximum intensity projections.

PURPOSE: Our goal was to evaluate the value of maximum intensity projections (MIPs) rendered from spiral CT in the assessment of abdominal aortic aneurysms after stent graft implantation. METHOD: Spiral CT of the aorta was performed in 28 patients 1 week after implantation of covered aortic stent grafts. MIPs were evaluated in a blinded fashion. Transaxial scans and intravenous angiographs were considered the reference standard. RESULTS: Stent deformity was evident on the MIPs in 5 cases and stent angulation was seen in 24 cases. The excluded aneurysmal sac was visualized in 14 (50%) cases. MIPs depicted the patent inferior mesenteric artery in 20 of 23 cases (87%). Renal artery occlusion (n = 3), leaks (n = 8), and parietal thrombi, (n = 3) were detected on the MIPs in all cases. CONCLUSION: MIPs are a valuable tool in the assessment of aortic stent grafts.

Aged↗