[Guidance of interventions in subintimal recanalization and fenestration of dissection membranes using a novel dual-lumen intravascular ultrasound catheter]. / Steuerung der Interventionen bei subintimaler Rekanalisation und Fenestration von Dissektionsmembranen durch einen neuartigen zweilumigen intravaskulären Ultraschallkatheter.

PURPOSE: To evaluate the feasibility and effectiveness of IVUS-guided puncture for gaining controlled target lumen reentry in subintimal recanalization of chronic iliac/femoral artery occlusions and in fenestration of aortic dissections. MATERIALS AND METHODS: Between 5/2004 and 12/2005 12 consecutive patients (7 male, 5 female; mean age 64.6 +/- 12.0 years) with chronic critical limb ischemia and ischemic complications of aortic dissection were treated using the Pioneer catheter. This 6.2-F dual-lumen catheter combines a 20-MHz IVUS transducer with a pre-shaped extendable, hollow 24-gauge nitinol needle. This coaxial needle allows real-time IVUS-guided puncture of the target lumen and after successful reentry a 0.014" guidewire may be advanced through the needle into the target lumen. 7 patients were treated for aortic dissection and 5 patients (with failed previous attempts at subintimal recanalization) for chronic arterial occlusion. Patients with aortic dissection (5 type A dissections, 2 type B dissections) had developed renal ischemia (n = 2), renal and mesenteric ischemia (n = 2), or low extremity ischemia (n = 3). Patients with chronic arterial occlusions (2 common iliac artery occlusions, 3 superficial femoral artery occlusions) experienced ischemic rest pain (n = 4), and a non-healing foot ulcer (n = 1). RESULTS: The technical success rate using the Pioneer catheter was 100%. The recanalization/fenestration time was 37 +/- 12 min. Procedure-related complications did not occur. In 10 cases a significant improvement of clinical symptoms was evident. One patient with aortic dissection and ischemic paraplegia required subsequent surgical intervention. One patient had persistent ischemic rest pain despite successful recanalization of a superficial femoral artery occlusion. CONCLUSION: The Pioneer catheter is a reliable device which may be helpful for achieving target lumen reentry in subintimal recanalization of chronic occlusions and in fenestration of aortic dissections.

Endovascular stenting of a renal transplant vein.

We describe successful endovascular stenting of a high-grade stenosis of a renal transplant vein in a 53-year old patient. Kidney transplantation had been performed due to IgA nephropathy and the patient had become symptomatic two months after uneventful recovery from operation.

Superselective embolization of deep femoral artery branch pseudoaneurysm with a coaxial microcatheter system.

This report describes the use of transluminal coil embolization to treat pseudoaneurysm of deep femoral artery branch in two patients. The pseudoaneurysms had developed after coronary angiographv in one patient and after hip replacement in the other. Immediate control angiography after embolization procedures demonstrated complete closure of the pseudoaneurysms. During follow-up of 19 and 3 months, respectively, there was no recurrent bleeding. The aim of this case report is to show the advances in endovascular microcatheter technology, and embolic materials, that made percutaneous transluminal embolization of arterial pseudoaneurysms safe and efficient. In addition, it keeps the medical personnel aware of vascular injuries at the access site related to endovascular procedures as well as vascular complications of total hip arthroplasty. It calls their attention to the possibility of endovascular treatment as an alternative to surgery.

Coil embolization of an infected superior gluteal artery pseudoaneurysm caused by methicillin-resistant Staphylococcus aureus.

We describe the successful selective coil embolization of an infected superior gluteal pseudoaneurysm secondary to methicillin-resistant Staphylococcus aureus (MRSA) in a 36-year old women. The patient presented with a long history of drug abuse and perisacral abscesses due to chronic sacroilitis. The chosen strategy provides a safe and successful management of infected false gluteal artery aneurysm.

Automated software supported versus manual aorto-iliac diameter measurements in CT angiography of patients with abdominal aortic aneurysms: assessment of inter- and intraobserver variation.

BACKGROUND: Open surgical or endovascular abdominal aortic aneurysm (AAA) relies on precise preprocedual imaging. Purpose of this study was to assess inter- and intraobserver variation of software-supported automated and manual multi row detector CT angiography (MDCTA) in aortoiliac diameter measurements before AAA repair. PATIENTS AND METHODS: Thirty original MDCTA data sets (4 x 2mm collimation) of patients scheduled for endovascular AAA repair were studied on a dedicated software capable of creating two-dimensional reformatted planes orthogonal to the aortoiliac center-line. Measurements were performed twice with afour-week interval between readings. Data were analysed by two blinded readers at random order Two different measurement methods were performed: reader-assisted freehand wall-to-wall measurement and semi-automatic measurement. RESULTS: Aortoiliac diameters were significantly underestimated by the semi-automatic method as compared to reader-assisted measurements (p < 0.0031). Intraobserver variability of AAA diameter calculation was not significant (p > 0. 15) for reader-assisted measurements except for the diameter of the left common iliac artery in reader 2 (p = 0.0045) and it was not significant (p > 0. 14) using the semi-automatic method. Interobserver variability was not significant for AAA diameter measurements using the reader-assisted method and for proximal neck analysis with the semiautomatic method (p > 0.27). Relevant interobserver variation was observed for semi-automatic measurement of maximum AAA (p = 0.0007) and iliac artery diameters (p = 0.024). CONCLUSIONS: Dedicated MDCTA software provides a useful tool to minimize aortoiliac diameter measurement variation and to improve imaging precision before AAA repair. For reliable AAA diameter analysis the reader-assisted freehand measurement method is recommended to be applied to a set of reformatted CT data as provided by the software used in this study.

Renal pathology after arterial yttrium-90 microsphere administration in pigs. A model for superselective radioembolization therapy.

RATIONALE AND OBJECTIVES: To test the selectivity of tissue damage in radioembolization, the authors performed an experimental study using superselective administration of yttrium-90 particles to deliver up to 100 Gy to the porcine kidney. Patterns and severity of damage in test organs were compared with controls, and the feasibility of this model is discussed. METHODS: Eight sows were included in the study. Bio-Rex 70 particles were applied via selective catheterization of the renal artery. Four pigs received inactive particles and four pigs received active particles. Organ distribution and shunting of yttrium-90 were determined, and kidney damage patterns were histologically analyzed. RESULTS AND CONCLUSIONS: The model demonstrates that yttrium-90-labeled resin particles can superselectively be applied. Retention of beta activity in the target organ was more than 95%. In addition to tissue shrinkage from mechanical obstruction, considerable damage ensued mainly by radiation-induced arterial necrosis and arteritis.

The fate of femoropopliteal and femorodistal bypass grafts in relation to intraoperative flow measurement: an analysis of 100 consecutive reconstructions for limb salvage.

Adequacy of outflow is the key determinant for success in peripheral arterial reconstructions. In an attempt to obtain reliable information on this parameter, we developed a new concept: the outflow through the recipient arterial bed is measured perioperatively. For this purpose, the recipient artery is cannulated and perfused with a saline solution from an open reservoir for 1 minute with a pressure of 120 cm H2O. In a prospective study, the outcome of 100 femoropopliteal and femorodistal bypass procedures, all performed for unremitting rest pain, nonhealing ischemic ulcers, or gangrenous tissue loss, is analyzed according to this 1-minute flow rate. Six grafts occluded, and major amputations were unavoidable in three additional patients despite an open bypass. Eight of these crucial events occurred in the group with a flow rate less than 50 ml/min. Two of four Gore-Tex grafts in the low flow category failed within the first postoperative month. In contrast, only one of 24 vein bypasses occluded within the same observation period. All patients having a postoperative flow exceeding 100 ml/min had open grafts in the 2-year observation period. It is concluded that although a diminished outflow rate of less than 50 ml/min represents a high risk failure of reconstructive vascular surgery, attempting a femorodistal bypass is still justified, especially if a vein of adequate size and quality is available as a graft substitute. However, the implantation of a prothetic bypass conduit to a single tibial vessel should be performed only in selected patients.

Computed tomography prior to second-look operation in advanced ovarian cancer.

Twenty-six patients treated with chemotherapy for ovarian cancer underwent a second-look laparotomy after clinical response (or in the absence of evidence of progressive disease). Abdominopelvic computed tomography (CT) was performed before this operation. Five patients (19%) who had been demonstrated as being free of disease by computed tomography were found to have a tumor larger than 1 cm. Computed tomography sensitivity was good in detection of lymph node metastases (83%), average for pelvic residual tumor (63%) and the omentum (50%), and low for other peritoneal locations (11%). Before second-look operation, the computed tomography scan provides useful surgical information about residual disease in retroperitoneal lymph nodes. However, negative computed tomography findings do not exclude residual tumor or confirm complete remission and therefore cannot replace the second-look laparotomy at this time.

Cytostatic lung perfusion by use of an endovascular blood flow occlusion technique.

BACKGROUND: Different modalities of cytostatic lung perfusion were compared regarding plasma and tissue drug concentrations to assess the efficacy of an endovascular blood flow occlusion technique. METHODS: A cytostatic lung perfusion study with doxorubicin hydrochloride was performed on large white pigs (n = 12). Plasma and tissue concentrations of doxorubicin were compared for isolated lung perfusion with open cannulation (ILP), blood flow occlusion perfusion with open cannulation of the pulmonary artery alone (BFO), and intravenous drug administration (i.v.). In a fourth group, thoracotomy-free BFO perfusion was performed by endovascular balloon catheterization of the pulmonary artery (endovascular BFO). The 3 animals in this group were used to compare the doxorubicin-perfused pulmonary tissue with the contralateral nonperfused lobes after 1 month. RESULTS: The mean lung tissue doxorubicin concentration at the end of perfusion was 19.8 +/- 1.6 microg/g after ILP, 27.6 +/- 2.2 microg/g after BFO (p = not significant), and 3.0 +/- 0.8 microg/g after i.v. perfusion (p < 0.01). Whereas doxorubicin was not detectable in the plasma in the ILP group, concentrations ranged from not detectable to 0.44 microg/mL in the BFO group and from 0.31 to 0.84 microg/mL in the i.v. group (p < 0.05). Mean myocardial tissue concentration was not significantly different after BFO than i.v. perfusion (1.1 +/- 0.5 microg/g and 1.8 +/- 0.1 microg/g, respectively). In the endovascular BFO group, balloon-blocked pulmonary artery perfusion was successfully performed in all animals, and after 1 month, lung tissue showed no cytostatic-induced histologic changes. CONCLUSIONS: Compared with ILP, BFO cytostatic lung perfusion produced an insignificantly higher lung-tissue concentration, corresponding to a sixfold to ninefold higher level than after i.v. perfusion. Plasma drug levels during BFO perfusion were lower than during i.v. perfusion. Endovascular BFO may be a promising technique for repeated cytostatic lung perfusion.

Acute hemorrhage in chronic pancreatitis: diagnosis and treatment options including superselective microcoil embolization.

Acute hemorrhage in the course of chronic pancreatitis is the most serious and challenging complication, and its treatment has been the subject of controversy for years. We relate our experience in the management of this complication by superselective microcoil embolization. Five patients with acute hemorrhage resulting from chronic pancreatitis between 1994 and 1997 were included in this study. All patients were men with a median age of 44 years (range, 29-59 years). The bleeding occurred into a pseudocyst in all patients, with the splenic artery as feeding vessel. In all instances, the bleeding was successfully controlled by superselective microcoil embolization. Two patients underwent subsequent uneventful elective pseudocystojejunostomy. There was no mortality or morbidity, and no rebleeding occurred during a median follow-up of 22 months (range, 8-36 months). In appropriate patients, diagnostic angiography and superselective microcoil embolization may obviate the need for emergency surgery and should be considered as treatment alternative.

Superselective microcoil embolization: treatment of choice in high-risk patients with extrahepatic pseudoaneurysms of the hepatic arteries.

BACKGROUND: Only a few isolated case reports of extrahepatic pseudoaneurysms of the hepatic arteries have been published. We present the first documented series of patients with extrahepatic pseudoaneurysms treated at a single institution, and discuss the etiology and management of this condition. STUDY DESIGN: A retrospective review of all cases of extrahepatic pseudoaneurysms of the hepatic arteries between 1989 and 1997. RESULTS: A total of seven patients with extrahepatic pseudoaneurysms of the hepatic arteries all had upper abdominal pain; five patients were also in shock secondary to a gastrointestinal bleeding from ruptured pseudoaneurysms. The most common factor of the pseudoaneurysms was previous pancreatobiliary surgery in five patients with blunt truncal trauma and chronic pancreatitis in the remaining two patients. Initial endoscopy and ultrasonography were unrevealing, whereas dynamic computed tomography (CT) scan and angiography were diagnostic. The median size of the pseudoaneurysms was 3.6 cm (range 2.1-5.7). Treatment consisted of superselective transcatheter microcoil embolization in five hemodynamically unstable patients and surgical resection of the pseudoaneurysms with vascular reconstruction in the two stable patients. Mortality and morbidity were 0% and 43%, respectively. In a median followup of 35 months (range 2-96), no recurrence of pseudoaneurysm has been found. CONCLUSIONS: A high index of suspicion combined with appropriate diagnostic modalities are required for the diagnosis of extrahepatic pseudoaneurysms. In high-risk patients, superselective transcatheter microcoil embolization should be considered the treatment of choice.

Total anomalous pulmonary venous connection to the portal and splenic vein associated with unilateral hypoplasia of pulmonary veins.

Total anomalous pulmonary venous return (TAPVR) represents a rare congenital anomaly with wide anatomical and physiological variability. We report a case of a newborn with a challenging form of obstructed infracardiac TAPVR, in whom left and right pulmonary veins drained separately into the portal system. The right pulmonary venous sinus connected to the left branch of the portal vein, whereas the left venous sinus connected to the splenic vein. Surgical repair consisted of the creation of a common retrocardiac venous trunk which was anastomosed to the left atrium. The postoperative course was characterized by persisting congestion of the right lung. Two months later, right pulmonary vein hypoplasia was successfully enlarged with autologous pericardium.

Embolization of a ruptured intercostal artery aneurysm in type I neurofibromatosis.

We present the case of a female with history of a ruptured lumbar aneurysm years ago. She was known to have neurofibromatosis type I with the typical clinical signs. The patient was transferred to us with a hematothorax and an aortic lesion was suspected on the outside CT scan. Reevaluation of the investigation raised suspicion of a ruptured intercostal artery aneurysm, which was consequently demonstrated on angiography. The aneurysm was embolized and the patient recovered uneventful. We will discuss the optimal therapy for vessel lesions in neurofibromatosis type I.

Establishing radiological percutaneous gastrostomy with balloon-retained tubes as an alternative to endoscopic and surgical gastrostomy in patients with tumours of the head and neck or oesophagus.

The purpose of this study was to report our experience introducing radiological percutaneous gastrostomy (RPG) catheters at a hospital where hitherto only endoscopic and surgical methods have been used. The feasibility, success, time requirements, and complications of RPG were prospectively evaluated during a 12-month period. 26 consecutive patients (median age 63 years, range 41-91 years) underwent gastropexy with T-fasteners followed by insertion of a 12-18 F balloon tube through a peel-away introducer and were followed-up clinically and radiologically. Success and complications occurring within 30 days were assessed. RPG was technically successful in all cases. Median procedure time was 34 min (range 20-90 min), median fluoroscopy time 6.9 min (range 2.3-30 min). 13 surgical gastrostomies were avoided. One minor complication (peristomal leakage) occurred in a patient with gastric reflux and atony. Another patient destroyed the balloon of his tube by injecting food into the balloon port, which led to tube dislocation and peritonitis. In conclusion, radiological gastrostomy can be quickly learned by radiologists and is readily accepted by clinicians. It is an alternative to surgical gastrostomy when percutaneous endoscopic gastrostomy is not feasible, but can also be used as the primary method instead of the endoscopic method.

Staging of hilar cholangiocarcinoma by ultrasound and duplex sonography: a comparison with angiography and operative findings.

The pre-operative radiological assessment of proximal bile duct tumours is clinically important as resection may be limited by tumour extension along the bile ducts, into hepatic parenchyma or the adjacent vascular structures. Demonstration of the extent of biliary and vascular involvement can direct additional investigations and definitive treatment. 22 patients with hilar cholangiocarcinoma were studied pre-operatively by conventional ultrasound (US) and duplex sonography (DS). The extent of tumour infiltration and vascular involvement was compared with arteriography and operative findings. Bile duct dilatation and the level of obstruction was documented by US in 22 (100%), and the tumour was shown by US in 19 (86%). In these 19 patients, the extent of extraductal extension compared with operative findings was correct in 13, underestimated in two, and in four infiltration was massed. Vascular patency or involvement was correctly determined by DS in 19 (86%), and by arteriography in 18 (82%). In two of the three incorrect DS interpretations, lobar atrophy and contralateral hypertrophy distorted the hilar anatomy. US with DS is valuable in the pre-operative staging of proximal bile duct tumours in predicting ductal and vascular involvement.

Combination of short- and long-term catheter thrombolysis for peripheral arterial occlusion.

To save time and expenses we developed a combined program of local short-term catheter thrombolysis (CTL) in the angiographic laboratory followed by a long-term CTL on the ward if necessary to achieve patency. Out of 66 patients with arterial occlusion in the femoro-popliteal region the occluded segment was re-opened by short-term CTL alone in 22 patients (36%), and in 24 out of the remaining 44 patients by long-term CTL, giving a total primary success rate of 71%. Angiographic analysis showed that primary clinical success depended on the patency of run-off vessels in the calf after CTL. Complications occurred in five patients, necessitating surgical revision in only one. Two years after intervention 64% of the primarily recanalized arteries were still patent as shown by non-invasive examination.

CT in advanced gastric carcinoma: is exploratory laparotomy avoidable?

The value of CT in the staging and assessment of resectability is demonstrated in 40 patients with advanced gastric carcinoma. The accuracy of CT using the pTNM classification of gastric carcinoma was 90% in the T category, 52.5% in the N category, 80% in the M category, and 72.5% as regards the correct staging. CT estimation of resectability was 80% correct. Based on these results, exploratory laparotomy is essential to evaluate the operability of gastric carcinoma. Exploratory laparotomy can only be avoided in patients with a proximal gastric carcinoma with clear CT demonstration of organ infiltration, N3 lymph node metastases, and distant metastases.

Subcapsular liver metastasis in ovarian cancer. Computed tomography and surgical staging.

In 38 patients with surgically-staged ovarian carcinoma, the role of CT scan in diagnosis of subcapsular liver metastases as well as its importance in determining the stage of ovarian carcinoma were investigated. Assessment of the perihepatic space was not possible intraoperatively in 14% of the cases because of tumourous adhesions. Subcapuslar metastases were revealed by CT scan in five (20%) patients whose livers were found normal during surgery (24 patients). In two of these (8%) the surgically-determined stage IIc had to be converted to stage III. These findings make a case for a more thorough visual examination of the dorsal surface of the liver during the staging process.

Value of computed tomography and lymphography in staging carcinoma of the uterine cervix.

CT scanning was performed on 68 consecutive patients with newly diagnosed, untreated carcinoma of the uterine cervix (FIGO stage IB-IVA). Lymphography was performed in 61 cases. Surgical pathological correlation was obtained in 16 patients. CT and clinical stage accorded only in 68%, mainly because of CT errors in the determination of parametrial involvement. CT detected enlarged lymph nodes in 60.5%, compared to 39.5% of cases with lymphographically demonstrated nodal metastases; this discrepancy resulted mainly from the inability of CT to discriminate benign nodal changes. Our data suggest lymphography as radiological staging procedure in early stage (IB, IIA) carcinoma and the routine use of CT in advanced stage (IIB-IV) disease.

Angioplasty of the terminal aorta: follow-up of 20 patients treated by PTA or PTA with stents.

Twenty patients with distal aortic stenosis were treated by PTA for intermittent claudication and, in 3, 'blue toe' syndrome. Additionally, a self-expandable endoprosthesis (stent) was inserted into the aorta in three of the patients. The overall primary success rate (including those with a stent) was 100% with all patients becoming free of symptoms. Mean arm-ankle pressure difference decreased from 48 mmHg to 9 mmHg (P less than 0.01). During a median follow-up period of 15 months no patient had recurrence of claudication, embolism, or deterioration of the non-invasive parameters. Thus, PTA seems suitable for treating stenoses of the abdominal aorta, even in the presence of distal microembolization. Balloon dilatation, with the addition of stents in resistant cases, offers a valuable alternative to surgery in distal aortic stenosis.