Symptomatic stenosis of the vertebrobasilar arteries: results of extra- and intracranial stent-PTA.

BACKGROUND AND PURPOSE: About half of all transient ischaemic attacks (TIAs) or strokes in the posterior circulation are caused by the arterial stenosis. The purposes of this study were to determine the safety of stent-assisted percutaneous transluminal angioplasty (stent-PTA) and its efficacy for the prevention of recurrent stroke in patients with symptomatic artery stenosis in the extra- and intracranial posterior circulation. METHODS: Forty-six patients with a previous stroke or TIA who received balloon-mounted coronary stents for vertebral artery origin stenosis (VAOS; 29 patients) or self-expanding nitinol stents for vertebrobasilar intracranial stenosis (VBIS; 17 patients) were followed-up for a mean of 24.1 (VAOS) and 12.7 (VBIS) months. RESULTS: When all cause morbidity/mortality within 30 days from stent-PTA and stroke or death from stroke in the treated vascular territory during the first 12 months of follow-up are combined, the incidence of periprocedural complications and disease progression for the first year is 10.3% in VAOS patients and 17.6% in the VBIS group. Vessel restenosis >/=50% was found in 52.0% of VAOS and in 32.1% of VBIS patients who completed 6 months follow-up. CONCLUSIONS: We observed a higher periprocedural complication rate for patients with VBIS and a higher rate of restenosis in VAOS patients after stent-PTA for symptomatic artery stenosis.

Diagnostic accuracy of 3D time-of-flight MR angiography compared with digital subtraction angiography for follow-up of coiled intracranial aneurysms: influence of aneurysm size.

BACKGROUND AND PURPOSE: 3D time-of-flight MR angiography (3D TOF MRA) may be used as noninvasive alternative to digital subtraction angiography (DSA) for the follow-up of patients with intracranial aneurysms treated with Guglielmi detachable coils (GDCs). We aimed to determine the influence of aneurysm size and location on diagnostic accuracy of 3D TOF MRA for follow-up of intracranial aneurysms treated with GDCs. MATERIALS AND METHODS: Two hundred and one 3D TOF MRAs in 127 consecutive patients with 136 aneurysms were compared with DSA as standard of reference. Sensitivity and specificity of 3D TOF MRA for detection of residual or reperfusion of the aneurysms was calculated with regard to aneurysm size and location. RESULTS: Overall sensitivity and specificity of MRA was 88.5% and 92.9%, respectively. Sensitivity was lower for aneurysms

Posttraumatic extracranial aneurysm of the internal carotid artery: combined endovascular treatment with coils and stents.

We report a case of a posttraumatic extracranial pseudoaneurysm of the internal carotid artery that was treated successfully via embolization with Guglielmi detachable coils and placement of a Wallstent after surgical repair failed.

Cerebral arteriovenous malformations: diagnostic value of echo-enhanced transcranial Doppler sonography compared with angiography.

BACKGROUND AND PURPOSE: The purpose of our study was to examine the clinical value of echo-enhanced transcranial power Doppler sonography (EE-TCD), including it ability to assess hemodynamic parameters of the intracranial vasculature, in patients with suspected cerebral arteriovenous malformations (AVMs) and to compare this method with angiography. METHODS: Sixteen patients with suspected cerebral AVMs were examined with EE-TCD and angiography. As an echo-enhancing agent, SHU 508A (Levovist) was administered intravenously by bolus injection in nine patients and by continuous infusion in seven. Sonograms were reviewed without knowledge of other imaging results and were correlated with angiographic findings. RESULTS: Angiography showed AVMs in 12 of 16 patients. Eleven lesions were located in the anterior or middle fossa and one was in the posterior fossa. EE-TCD was slightly less sensitive in the detection of AVMs (92%, 11/12 lesions), since in one patient the lacking acoustic window did not allow a transcranial examination. EE-TCD slightly underestimated AVM size compared with angiographic findings but showed feeding arteries with sufficient acoustic properties. In seven patients (58%), angiography revealed a coincidental blood supply from another intracranial or extracranial vessel, which was missed by EE-TCD in all cases. Assessment of peak systolic velocities and resistive indexes resulted in a higher (mean, 191.1 cm/s) and a lower (mean, 45.7%) value, respectively, in the feeding arteries as compared with the contralateral arteries (mean, 101.8 cm/s and 55.6%, respectively). Side-to-side differences were significantly higher in patients with AVMs than in those without a malformation. Signal enhancement was markedly longer with continuous infusion (mean, 520 seconds +/- 28.2) than with bolus injection (mean, 145 seconds +/- 10.5) of the contrast agent. CONCLUSION: In our limited study group, EE-TCD was a sensitive method for the detection of AVMs, and Levovist proved to be a safe and effective echo-enhancing substance.

Helical high-resolution volume-rendered 3-dimensional computer tomography angiography in the detection of intracranial aneurysms.

BACKGROUND AND PURPOSE: This study was carried out to determine whether high-resolution 3-dimensional prospective-volume-rendered computed tomographic (CT) angiography can replace conventional intra-arterial digital subtractional angiography in the diagnostic evaluation of patients with an acute subarachnoid hemorrhage (SAH) due to ruptured intracranial aneurysm. METHODS: Both techniques were performed in 30 consecutive patients within 2 to 12 hours after their admission to the hospital. RESULTS: In this group of 30 patients, CT angiography with 3-dimensional volume-rendered reconstruction detected 31 aneurysms in 25 patients. Two aneurysms were missed on CT angiography. Conventional angiography detected 33 aneurysms in 27 patients. The authors considered angiograms in 3 patients presenting with SAH as normal. In all cases where an aneurysm was detected on CT angiography, the finding was confirmed by conventional angiography. CONCLUSIONS: CT angiography with 3-dimensional post-processing is a sensitive, noninvasive method that provides a 3-dimensional view of intracranial vessels and the aneurysm. It is also very useful in planning either surgical or endovascular treatment.

[Clinical experiences with the transjugular intrahepatic portocaval shunt (TIPS)]. / Klinische Erfahrungen mit dem transjugulären intrahepatischen portokavalen Shunt (TIPS).

Twenty-five patients with liver cirrhosis and portal hypertension were admitted for creation of a transjugular intrahepatic portosystemic shunt (TIPS). The procedure was successful in 22 patients (technical success 88%). The mean portal pressure gradient was lowered from 24.5 mmHg before to 11.4 mmHg after TIPS. Two early and three late occlusions were observed (primary patency rate 78%). The rate of secondary interventions was 41%. Five times a hepatic vein stenosis was dilated and stented, two times an occluded shunt was recanalized, two times a new shunt was created parallel to an occluded (secondary patency rate within a maximum of 16 months 95%). In two patients sepsis occurred which was effectively treated with antibiotics, two patients died shortly after TIPS due to hepatorenal syndrome and hepatic failure, respectively. There was no recurrent bleeding. Two patients developed hepatic encephalopathy; both improved after protein restriction. The authors conclude that TIPS is an alternative procedure to shunt surgery, especially for patients who cannot benefit from sclerotherapy.

[Percutaneous recanalization of pelvic artery occlusions--fibrinolysis, PTA, stents]. / Perkutane Rekanalisation von Beckenarterienverschlüssen--Fibrinolyse, PTA, Stents.

In 42 patients with symptomatic chronic iliac artery occlusions with a length of 2-15 cm (mean 4.3 cm), percutaneous recanalization was attempted. The study population was divided into 2 groups: Group I (n = 17) is a retrospective control group, the patients were treated with fibrinolysis (FL) and percutaneous transluminal angioplasty (PTA). In group II (n = 25) the patients were treated according to a prospective protocol including FL, PTA and placement of endovascular self-expandable stents. The recanalization rate for Group I and II together was 83% (35/42). FL was effective in 47%, in 53% the recanalization was performed mechanically only. The patency rate in Group I during a maximum of 69 months was 67%, in Group II, in which residual stenoses were treated with stents, 100% during max. 18 months. Obviously stents help to improve the results after percutaneous recanalization of iliac artery occlusions significantly.

[Endoluminal therapy of infrarenal aortic aneurysms with the Talent system--initial experiences with a new endoprosthesis]. / Endoluminale Therapie infrarenaler Aortenaneurysmen mit dem Talent-System--Erste Erfahrungen mit einer neuen Endoprothese.

PURPOSE: To report the early clinical experience with the Talent stent-graft system in the treatment of infrarenal aortic aneurysms. MATERIALS AND METHODS: The study group comprised 15 males aged from 51-79 years. A bifurcated Talent stent-graft was implanted in 9 patients with type B or C aneurysms, a tube graft in 6 patients with a type A aneurysm. The stent-grafts were introduced via a surgical femoral cut-down, for a bifurcated graft a bilateral surgical access was needed. All procedures were performed as teamwork by radiologists and vascular surgeons under general anaesthesia in the angiography suite. RESULTS: Primary and secondary technical successes were 80 and 86%, respectively. Technical failures were due to access site problems (n = 1; elective open repair), malpositioning of the prosthesis (n = 1; immediate conversion to open surgery), and primary distal leakage (n = 1; elective occlusion by means of distal stent-graft extension). One patient died 15 days after an uneventful stent-graft insertion (30-day mortality 6%). No complications were observed during a mean follow-up period of 7.8 months. The aneurysmal diameter decreased in 6 patients and remained unchanged in the others. CONCLUSIONS: The Talent system revealed satisfactory early results which are comparable to competitive stent-graft systems. An advantage of this stent-graft device is the availability in a wide range of dimensions. A major disadvantage is the large introducer system (french size 22-27).

[Fluoroscopically guided percutaneous fine-needle biopsy of the lung using the ROTEX needle: results in 890 patients with focal lung lesions]. / Durchleuchtungsgezielte perkutane Feinnadelbiopsie der Lunge mit der ROTEX-Nadel. Ergebnisse bei 890 Patienten mit fokalen Lungenläsionen.

Fluoroscopically guided transthoracic fine needle biopsies were performed in 890 patients (380 female, 582 male, mean age: 56 years). In 795 patients (89.4%) the first biopsy was successful. The success rate of biopsy correlated closely with the size of the lesion and increased with larger size. Sensitivity in the diagnosis of malignant lesions was 94.6%, specificity 99.5%. Due to cytological, histological, and clinical confirmation of benign lung lesions in 300 patients (33.7% of all patients), the number of unnecessary diagnostic thoracotomies for benign disease could be reduced significantly. In 9 of 113 cases (8%) histological reclassification of the cytologic results was necessary. Reclassification was not necessary in the differentiation between benign and malignant lesions and between small cell and non-small cell carcinomas. The overall complication rate was 24.7% (220 patients). Only 36 patients (4% of all patients) required chest-tube insertion. There were no fatal complications. Percutaneous fluoroscopically guided transthoracic fine needle biopsy of the lung, performed with the Rotex needle, is a time-effective, safe, and efficient method for diagnosing focal pulmonary lesions.

[Metallic mesh endoprosthesis and intraluminal high dose rate 192Ir brachytherapy in the palliative treatment of malignant bile duct obstruction. Initial results]. / Metallgeflecht-Endoprothese und intraluminare High-dose-rate-192Iridium-Brachytherapie zur palliativen Behandlung maligner Gallengangsobstruktionen. Erste Erfahrungen.

Since December 1989, 9 patients with inoperable malignant biliary tract obstruction were treated palliatively by a combined modality treatment consisting of placement of a permanent biliary endoprosthesis followed by intraluminal high dose-rate 192Ir brachytherapy. A dose of 10 Gy was delivered in a hyperfractionated schedule at the point of reference in a distance of 7.5 mm of centre of the source. External small field radiotherapy (50.4 Gy, 1.8 Gy per day, 5 fractions per week) was also given in six cases (M/O, Karnofsky greater than 60%). In 9/9 cases an unrestrained bile flow and an interruption of pruritus was achieved, in 78% (7/9) of cases the duration of palliation was as long as the survival time (median survival time 7.5 months).

White fingers after excessive motorcycle driving: a case report.

An 18-year-old male presented with Raynaud's phenomenon which was found to be caused by occlusion of the proper palmar digital arteries on the right hand and obstruction of the superficial palmar arterial arch on the left hand. These lesions in the arteries of both hands resemble those found in patients with vibration-induced white fingers such as in mine or foundry workers. The only likely cause for the pathological vascular findings in our patient was an exposure to vibration due to excessive off-street motorcycle driving. Therapy with intraarterial prostaglandins resolved the ischemic syndrome but it promptly recurred when the patient resumed motor cycle driving. Therefore, we suggest that excessive cross country motor cycle driving may cause vibration-induced white fingers.

Long-term follow-up after treatment of intracranial aneurysms with the Pipeline embolization device: results from a single center.

BACKGROUND AND PURPOSE: Stent-like, self-expandable devices, the so-called flow diverters, are increasingly used for the treatment of wide-neck cerebral aneurysms. The immediate and short-term results are promising, but no long-term results are available. The purpose of our research was to report the long-term angiographic and cross-sectional imaging results after placement of a PED in 12 patients with wide-neck intracranial aneurysms. MATERIALS AND METHODS: Twelve wide-neck or otherwise untreatable cerebral aneurysms in 12 patients were treated with the PED. Angiography was performed at 6 and 24 months after treatment. Additional MR and CT angiograms were acquired. RESULTS: In all patients, angiographic or cross-sectional imaging follow-up of at least 27 months demonstrated complete occlusion of the aneurysms treated with the PED. There were no cases of aneurysm recurrence. Angiography at around 6 months showed complete occlusion in all cases, except 1 that showed complete occlusion at the 29-month follow-up. In 1 patient, a clinically asymptomatic 75% in-stent stenosis was seen on the angiography at 6 months but was resolved completely by balloon dilation. Device placement was successful in all patients. Distal embolization had occurred in 1 patient, but the clot was resolved completely without clinical sequelae. Almost immediate angiographic occlusion was achieved in 2 aneurysms and flow reduction in 10 aneurysms. CONCLUSIONS: Treatment of wide-neck intracranial aneurysms by PED placement led to successful and durable occlusion in all cases, without severe complications. Endovascular treatment for in-stent stenosis should be considered cautiously, because the underlying stenosis may be transient and disappear within 12 months after treatment.

[Preoperative angiographic embolization of carotid glomus tumors. A method for improving operability]. / Die präoperative angiographische Embolisation von Tumoren des Karotisglomus. Eine Methode zur Verbesserung der Operabilität.

During surgical resections carotid body tumors may bleed profusely due to their vascularity. Preoperative angiographic embolization of tumor-supplying arteries has reduced intraoperative blood loss significantly. The present study reviews our clinical experiences with 13 paragangliomas of the carotid bifurcation in 12 patients during the past 5 years. In 6 patients (46.1%) computed tomography and magnetic resonance imaging demonstrated extensive spread of the tumor up to the base of the skull. Tumors of this size were initially assessed as being inoperable but curative surgical resections were performed after embolization of tumor-supplying arteries by intravascular injections of Gelfoam and implantations of microcoils. Vascular reconstruction of the internal carotid artery by a saphenous vein graft was required in 4 patients (30.7%). In 3 malignant paragangliomas (23.0%) adjuvant radiotherapy of 50-60 Gy was administered to the tumor site after surgery. During an average follow-up of 29 months, one malignant paraganglioma was found to have recurred locally 13 months after initial therapy.

Ruptured vertebrobasilar junction aneurysm associated with basilar artery fenestration.

A case of a ruptured saccular aneurysm arising from the proximal portion of a partially duplicated basilar artery in a 36-year-old woman is reported. CT and lumbar puncture confirmed subarachnoid haemorrhage. Cerebral angiography detected a vertebrobasilar junction aneurysm associated with basilar artery fenestration. The patient underwent successful clipping and coating of the aneurysm by a right lateral suboccipital osteoclastic approach. Embryological development, pathogenesis, diagnostic and therapeutic difficulties of this vascular malformation are discussed in this report.

Obstructive jaundice: use of expandable metal endoprosthesis for biliary drainage. Work in progress.

Expandable metal endoprostheses were implanted transhepatically in 61 patients with obstructive jaundice. Fifty-three patients had malignant and eight had benign obstructions. Because of the small diameter of the compressed stent (7 F), primary implantation of the stent without a previous catheter drainage was preferred. Postprocedural complications occurred in three patients (5%) (biliary pleuritis, peritonitis, hepatic artery aneurysm). The 30-day mortality rate was 8.2%. Reocclusions were observed in six of the patients with malignant obstructions (11%) (observation period, 1-10 months; mean, 4.5 months) and in two of the patients with benign stenoses (25%) (observation period, 3-21 months; mean, 9 months). The higher reocclusion rate of benign obstructions must be interpreted with care because of the small number of patients. From their preliminary experience, the authors conclude that expandable metal endoprostheses offer patency rates equal to those of plastic stents. The implantation trauma is reduced due to the small 7-F introducing catheter system.

Strength, elasticity, and plasticity of expandable metal stents: in vitro studies with three types of stress.

PURPOSE: Five types of expandable metal stents (Palmaz, Strecker, Gianturco, Cragg, and Wallstent) were subjected to standardized tests to obtain objective, comparable data of their mechanical characteristics. MATERIALS AND METHODS: The stents were subjected to area loads, point loads, and circular loads; the resistance of the stents to a continually increasing deformation was measured. Elasticity and deformation characteristics of the stents were also noted. Another experiment simulated the situation of the stent in an implanted state. The stents were covered with a thin self-adhesive foil to simulate optimal wall contact by limiting the mobility of the mesh struts. RESULTS: For all types of stress, the Palmaz stent showed the highest resistance but was completely inelastic. The Strecker stent and the Wallstent showed higher resistance when coated in foil (simulating good wall contact). The Gianturco stent showed the lowest resistances but was completely elastic. A point load on a Wallstent caused concentric constriction over a longer distance. CONCLUSIONS: Palmaz stents are appropriate for insertion into highly resistant obstructions. Strecker stents and Wallstents require good wall contact to achieve adequate strength. Because of their unique deformation characteristics, Wallstents may not function well if implanted into eccentric stenoses of tough consistency. The Gianturco stent showed the lowest resistances.

Malignant biliary obstruction: histologic findings after treatment with self-expandable stents.

Histologic analysis was performed of bile duct tissue from 15 patients who underwent treatment for malignant obstructive jaundice with a self-expandable stent. Stents were in place from 5 days to 21 months. Malignancies included adenocarcinoma of the pancreas or gallbladder or cholangiocellular, hepatocellular, or gastric carcinoma. Stents were blocked by sludge in two cases and tumor overgrowth in two others. Microscopic evaluation showed that stent placement caused complete denudation of the mucosa and mild submucosal inflammation with edema. In all but one patient, the stent was incorporated into the bile duct wall and was covered by a fibrogranulomatous tissue layer after 2 months. In some cases, an epithelium-like cell formation covered the inner surface of the stent. Tumor ingrowth was observed in two patients with poorly differentiated tumors. In stents placed for longer than 2 months, mild to moderate fibrosis and foreign body reaction were observed. Hyperplastic biliary epithelium was not found within the stent or at the stent ends.

Pulsed excimer laser versus continuous-wave Nd:YAG laser versus conventional angioplasty of peripheral arterial occlusions: prospective, controlled, randomised trial.

Early clinical studies of coronary and peripheral laser angioplasty showed that arterial occlusions could be recanalised by continuous-wave lasers delivered with contact probes and by pulsed lasers applied with multifibre catheters. However, whether laser-assisted angioplasty improves success rates in reopening occlusions and in long-term patency rates is unclear. We have compared the primary recanalisation and long-term patency rates after laser-assisted and conventional percutaneous transluminal angioplasty (PTA) of femoropopliteal artery occlusions in 116 consecutive symptomatic patients (excimer laser 37, Nd:YAG laser 40, PTA 39). Primary recanalisation was achieved in 81 patients (70%). The primary recanalisation rate achieved with the excimer laser was significantly lower than that with the Nd:YAG laser (49% vs 78%, p < 0.01) or with PTA (82%, p < 0.003). The overall angiographic recanalisation rate (primary and secondary recanalisation) after laser and PTA was 89%. After 3 months, clinical improvement was recorded in 76% of patients. Clinical long-term results were available in 94 (91%), and angiographic long-term results in 77 (75%), of 103 successfully recanalised patients. Life-table analysis of the long-term results revealed no significant difference of the restenosis rate between the three treatment groups. The 12-month patency rate was 60% as assessed clinically and 39% as judged by angiography. Primary and secondary recanalisation rates and long-term patency rates were significantly correlated with length of the occlusion. Our results suggest that PTA of femoropopliteal artery occlusions is only indicated if the occlusion is short (< 8 cm) and that laser-assisted angioplasty should only be used after failure of conventional PTA.