Walter A. Wohlgemuth

Effects of intravenous opioids on eye movements in humans: possible mechanisms

Oculomotor symptoms such as downbeat nystagmus can be due to side effects of drugs. We investigated the clinical effects as well as the eye movement symptoms after intravenous administration of opiates (pethidine and fentanyl). Eye movements were recorded with the magnetic search coil technique. All four normal subjects showed a transient disturbance of eye fixation with downbeat nystagmus, a range of saccadic intrusions and oscillations, including square wave jerks and saccadic pulses, lasting from 10 to 15 minutes. The gain of sinusoidal VOR and smooth pursuit was moderately decreased; in particular the vertical pursuit showed an upward velocity offset. On the basis of the clinical findings and of recent diprenorphine PET findings in humans, which detected opiod binding sites in the cerebellum and the known inhibitory action of opiates, we hypothesized that a cerebellar dysfunction occurs after opiate administration which could possibly be mediated by inhibition of the parallel fiber activation of the Purkinje cells. Furthermore, opiate binding sites in the vestibular nuclei could be responsible for the vertical vestibular tonus imbalance involved in the pathophysiolgy of downbeat nystagmus.

MRI, CT, US and ERCP in the evaluation of bile duct hamartomas (von Meyenburg complex): a case report

Abstract. A case of multiple bile duct hamartomas (von Meyenburg complex) of the liver accompanied by exudative and in part necrotizing pancreatitis is presented. Magnetic resonance imaging (fat suppressed, T2-weighted images with prolonged echo time) could exclude diffuse tumor infiltration of the liver, which had not been possible with CT, sonography, or ERCP. To our knowledge, no comparable case has been reported.

PTA arid stenting of benign venous stenoses in the pelvis: Long-term results

AbstractPurpose: To provide follow-up data on endovascular intervention for venous stenoses in the pelvis. Methods: Between 1985 and 1995, 35 patients presented with 42 stenoses of the pelvic veins after operative thrombectomy and creation of an arteriovenous fistula, combined with intraoperative venous angioscopy. All patients underwent angioplasty and, if unsuccessful, percutaneous insertion of an endovascular stent (n=7). Results: Angioplasty with and without endovascular stenting was technically successful in 34 of 35 patients (97%). Average length of the stenoses was 20.6 mm (range 10–90 mm), average diameter before dilation 4.1 mm (range 2–6 mm), and average diameter after dilation 10.1 mm (range 5–18 mm). Intraoperative angioscopy showed pathologic findings (intimal laceration or residual thrombotic material) in 14 patients. After an average follow-up period of 4.13 years. 24 (69%) patients had patent veins. The difference in the primary patency rate between patients with angioscopically abnormal veins (6 of 14 patients, corresponding to a patency rate of 43%) and patients with angioscopically normal veins after thrombectomy (18 of 21 patients, corresponding to a patency rate of 86%) was statistically significant (p<0.01, log rank test). Conclusions: Percutaneous transluminal angioplasty and/or stenting are good treatment modalities for pelvic vein stenosis following surgical thrombectomy. Angioscopically abnormal veins have a poorer long-term patency, regardless of the type of intervention.

Dynamic evaluation and quantification of microvascularization during degradable starch microspheres transarterial Chemoembolisation (DSM-TACE) of HCC lesions using contrast enhanced ultrasound (CEUS): A feasibility study

PURPOSE To evaluate the time dependent changes of microcirculation in hepatocellular carcinoma (HCC) lesions during degradable starch microsphere (DSM)-TACE using contrast enhanced ultrasound (CEUS). MATERIALS AND METHODS A total of 48 CEUS examinations were performed (1-5 MHz, convex probe) in 6 selected patients who underwent DSM-TACE with EmboCept®S for the treatment of HCC lesions. I.v. application of ultrasound contrast media was performed before and 24 hours post embolization. In addition i.a. contrast application was performed via the angiographic catheter right before and after the embolization and during a follow up time of 2 hours every 30 minutes. The capillary circulation of the treated HCC lesions was analyzed and quantitative perfusion analysis was performed using a perfusion software by two experienced radiologists in consensus. RESULTS A significantly reduced microvascularization was seen right after DSM-TACE in all cases using CEUS. The reduction of PEAK, RBV (regional blood volume) and RBF (regional blood flow) compared to preembolization values was highly significant. Mean PEAK was 34.3 ± 13.1 prior to embolization and 9.4 ± 9.1 post embolization (p < 0.001). Mean RBV was 446.5 ± 122.4 prior to embolization and 70.9 ± 23.8 post embolization (p < 0.001). The corresponding figures for RBF were 34.7 ± 13.4 prior- and 4.8 ± 3.4 post embolization (p < 0.001). During follow up a stepwise revascularization of the lesions was documented: 90 minutes post embolization perfusion parameters were not significantly different from prae-embolization values. CONCLUSION In this feasibility study, capillary perfusion quantification of HCC lesions after DSM-TACE could be demonstrated using CEUS. Using quantitative perfusion analysis it was possible to quantify the transient embolizing effect of DSM-TACE.

Visualization of the Basilar Artery By Transcranial Color-Coded Duplex Sonography Comparison With Postmortem Results

BACKGROUND AND PURPOSE Transcranial color-coded sonography (TCCS) via the suboccipital approach allows direct and continuous visualization of the basilar artery (BA). In this study, we intended to evaluate the ability of native TCCS in visualizing the length of the BA by means of a comparison with postmortem measurements. METHODS The BA was prospectively studied by TCCS shortly before death (median 3 days) in 46 moribund neurological patients (mean+/-SD age 71.1+/-13.1 years). The length of the BA was determined by measuring the distance between the vertebrobasilar junction and the deepest available flow signal in the top of the BA. During autopsy, photos of the vertebrobasilar system were taken to evaluate the true anatomic length and variations of the course of BA in situ, eg, straight, curved, or S-shaped. RESULTS Comparison of the in vivo ultrasound measurements of BA length and postmortem data was possible in 44 of 46 cases. In the 2 remaining patients, the BA was occluded. The mean insonation depth of the vertebrobasilar junction was found at 66.9+/-7.1 mm. The mean BA length was 21.5+/-6. 8 mm by color-coded duplex and 32.9+/-6 mm anatomically (P<0.0001). The mean difference between color mode and anatomic findings was 11. 3+/-6.4 mm in the case of a straight BA (35 cases) and 16.3+/-4.8 mm in an anatomically tortuous course of the BA (9 cases). CONCLUSIONS Color duplex imaging enables correct visualization of the proximal two thirds of the BA, but only exceptionally of its distal one third. A tortuous course of the BA leads to an underestimation of its anatomic length.

CT Features of Early Type II Endoleaks after Endovascular Repair of Abdominal Aortic Aneurysms Help Predict Aneurysm Sac Enlargement

PURPOSE To determine computed tomographic (CT) features of early type II endoleaks associated with aneurysm sac enlargement after endovascular aortic aneurysm repair (EVAR) of abdominal aortic aneurysm. MATERIALS AND METHODS Institutional review board approval was not required for this retrospective study. The authors reviewed imaging and clinical data from 56 patients (seven women, 49 men; mean age ± standard deviation, 71 years ± 7.9; age range, 52-85 years) with early type II endoleak who had undergone EVAR between December 2002 and December 2011 and who had been followed up with imaging and clinical evaluation for at least 6 months. The number and diameter of all feeding and/or draining arteries were measured, and endoleaks were classified according to their sources into simple inferior mesenteric artery (IMA), simple lumbar artery (LA), complex LA, and complex IMA-LA type II endoleaks. Volume and attenuation of the nidus were measured. Aneurysm enlargement was defined as an increase in the aneurysm volume of more than 5% during follow-up. Simple and multivariate logistic regression analyses were performed to identify independent clinical and imaging variables associated with aneurysm enlargement. RESULTS Twenty-three of the 56 patients (41%) showed aneurysm sac enlargement during follow-up (mean follow-up, 3.0 years ± 2.0). With the multivariate model, the variables that showed the strongest indicators for aneurysm sac enlargement were complex IMA-LA type II endoleak (odds ratio [OR] = 10.29, P = .004) and the diameter of the largest feeding and/or draining artery (OR = 4.55, P = .013). Patients without complex IMA-LA type II endoleak in whom the largest feeding and/or draining artery was larger than 3.8 mm and patients with a complex IMA-LA type II endoleak in whom the largest feeding and/or draining artery was larger than 2.2 mm were at high risk for aneurysm sac enlargement. CONCLUSION The strongest indicators for aneurysm sac enlargement are complex IMA-LA type II endoleak and the diameter of the largest feeding and/or draining artery.

Inferior Mesenteric Arterial Type II Endoleaks after Endovascular Repair of Abdominal Aortic Aneurysm: Are They Predictable?

PURPOSE To evaluate the association of inferior mesenteric arterial (IMA) type II endoleaks in patients undergoing endovascular aortic aneurysm repair (EVAR) for infrarenal abdominal aortic aneurysm with several morphologic parameters. MATERIALS AND METHODS Approval of the institutional ethical review committee was not required. This was a retrospective review of 322 computed tomographic angiographic studies that were performed in patients before they underwent elective EVAR for infrarenal abdominal aortic aneurysm. Morphologic parameters evaluated were IMA patency, origin of the IMA in relation to the aneurysm sac, diameter of the IMA, the cross-sectional area of the contrast material-enhanced aortic lumen at the level of the IMA ostium, and the number of additional patent aortic side branches from the aneurysm sac. The association of IMA type II endoleaks with each variable was analyzed by using univariate and multivariate logistic regression models. RESULTS The diameter of the IMA did not influence the development of IMA type II endoleaks (P = .51). The incidence of these endoleaks was significantly higher in patients with greater cross-sectional area of the aortic lumen at the IMA ostium (P < .001). Patients with an IMA type II endoleak had significantly more patent aortic side branches before EVAR than did patients without an endoleak (3.6 ± 1.7 vs 2.2 ± 1.4; P < .001). According to the final logistic regression model that included cross-sectional area of the aortic lumen at the IMA and the number of aortic side branches as independent predictors, risk for IMA type II endoleaks was determined with a sensitivity of 78% (39 of 50) and a specificity of 79% (92 of 116). CONCLUSION Cross-sectional area of the contrast-enhanced aortic lumen at the level of the IMA ostium and the number of additional patent aortic side branches are associated with the development of IMA type II endoleaks.

Intermittent claudication due to ischaemia of the lumbosacral plexus

The distinct clinical syndrome of exercise induced ischaemia of the lumbosacral plexus is not a widely known cause for intermittent claudication. Eight patients with the mentioned syndrome were investigated clinically, neurophysiologically, and with imaging techniques. The clinical examination showed a typical exercise induced sequence of symptoms: pain, paraesthesia, and sensory and motor deficits. The underlying vascular conditions were high grade stenoses or occlusions of the arteries supplying the lumbosacral plexus. Spinal stenosis could be excluded in all cases. Five patients received successful interventional radiological therapy. The syndrome can be diagnosed clinically and successful therapy is possible by interventional radiology.

Ultrasonography of acute musculoskeletal disease.

Abstract. With technical improvements (higher frequency and extended field-of-view sonography) the ability of ultrasound to detect pathology in the musculoskeletal system has been greatly increased. As in MRI, and unlike conventional radiography, soft tissue lesions in muscles, tendons and occasionally in joints can be shown directly. An advantage is real-time imaging of joints during stress. A disadvantage is limited demonstration of internal structures within joints. This paper provides an overview of various pathologies with emphasis on acute disorders.

Percutaneous Transhepatic and Transsplenic Portal Vein Access: Embolization of the Puncture Tract Using Amplatzer Vascular Plugs

PURPOSE To report on first results of the embolization of transhepatic and transsplenic puncture tracts using an Amplatzer Vascular Plug (AVP) after percutaneous portal vein intervention. MATERIALS AND METHODS Embolization of transhepatic and transsplenic puncture tracts with AVP was attempted in 5 patients (3 females; age range: 3 - 71 years). Portal vein access was gained by a transhepatic (n = 4) or transsplenic (n = 1) approach, and stenosis (n = 2) or thrombosis (n = 3) of the portal vein was successfully treated by percutaneous stenting or thrombus aspiration and thrombolysis using 6 to 10 French sheaths. Due to the relatively large bore and/or short transparenchymal puncture tracts, it was considered favorable to use AVPs as an embolic agent. The medical records, the radiological reports and images of these 5 patients were retrospectively evaluated. RESULT In three cases one AVP II (diameter, 4 mm), in one case one AVP IV (diameter, 4 mm) and in one case two AVPs II (diameter, 8 and 6 mm) were used for embolization of the puncture tract. In all five cases embolization was technically successful. There was no bleeding from the puncture tract. During a median follow-up of 14 months (range, 21 days to 21 months), one patient developed a focal liver abscess adjacent to the AVP which was successfully treated by antimicrobial and drainage therapy. There were no further embolization-related complications. CONCLUSION AVPs are suited to embolize large bore and/or short transhepatic and transsplenic puncture tracts effectively, safely, and precisely. Caution is required in patients with an increased risk for infectious complications. KEY POINTS • Embolization of transhepatic and transsplenic puncture tracts with AVPs is feasible• Large and/or short puncture tracts can be effectively embolized with AVPs• The risk of infectious complications has to be considered Citation Format: • Dollinger M, Goessmann H, Mueller-Wille R et al. Percutaneous Transhepatic and Transsplenic Portal Vein Access: Embolization of the Puncture Tract Using Amplatzer Vascular Plugs. Fortschr Röntgenstr 2014; 186: 142 - 150.