PubMed Health⌕ Search

Biomedical subjects

Werner Jaschke

Publications and source records attributed to Werner Jaschke.

At least 19 recordsLinked to original sources

Progression of putaminal degeneration in multiple system atrophy: a serial diffusion MR study.

By using diffusion-weighted imaging (DWI), we have recently shown abnormal diffusivity in the putamen of patients with the Parkinson variant of multiple system atrophy (MSA-P) which also correlated with disease severity, indicating the capability of putaminal diffusivity to serve as a marker for disease progression. We therefore performed a serial DWI study in 10 patients with MSA-P compared to 10 patients with Parkinson's disease (PD) to evaluate the dynamic evolution of diffusion properties in the basal ganglia including putamen, caudate nucleus and globus pallidum by means of the trace of the diffusion tensor (Trace(D)). For comparison, we have also analyzed the frequency and semiquantitative grading of MSA-P-related structural changes on conventional MRI including putaminal atrophy, lateral hyperintense margination of the putamen and putaminal signal hypointensity relative to the globus pallidum on T2 MR images. None of the Trace(D) values in the basal ganglia regions in the PD group changed significantly at follow-up compared to baseline. In MSA-P, a significant increase of the Trace(D) was found in the putamen, which correlated with motor progression as assessed by the Unified Parkinson's Disease Rating Scale (UPDRS). No significant change of any of the abnormal putaminal findings on routine MRI was obtained. We suggest that abnormal diffusivity in the putamen is sensitive to change over time in MSA-P and correlates with motor progression indicating that DWI may serve to monitor disease progression in MSA-P in an objective and quantitative manner.

Aged↗

Topography of putaminal degeneration in multiple system atrophy: a diffusion magnetic resonance study.

There is neuropathologic evidence that, in early stages of the Parkinson variant of multiple system atrophy (MSA-P), the putamen shows a distinct topographical pathology affecting predominantly the dorsolateral and caudal regions while leaving the rostral to midparts almost intact. We investigated the topographic profile of putaminal degeneration in MSA-P patients in vivo by means of diffusion-weighted imaging (DWI), which has been shown to reveal abnormalities in the basal ganglia of patients with MSA-P compared to patients with PD and healthy controls. For this purpose, regional trace of the diffusion tensor (rTrace(D)) values were determined in the entire, anterior, and posterior putamen in 15 patients with probable MSA-P, in 20 patients with PD, and in 11 healthy volunteers matched for age and disease duration. MSA-P patients had significantly higher rTrace(D) values in entire, anterior, and posterior putamen compared to both controls and PD patients. Trace(D) values were significantly higher in the posterior compared to the anterior putamen in the MSA-P group. There were no significant differences between posterior and anterior putamen in both the control and PD group. Our study demonstrates prominent involvement of the posterior putamen in early disease stages of MSA-P in vivo by assessing putaminal diffusivity with the help of DWI.

Humans↗

Voxel-wise analysis of diffusion weighted imaging reveals disruption of the olfactory tract in Parkinson's disease.

Diffusion weighted imaging (DWI) and the trace of diffusion tensor [Trace (D)], a marker of water molecule diffusivity, provide information on structural integrity of nervous tissues. To investigate structural lesions within the brain's neuronal architecture in early stages of Parkinson's disease, 12 patients with disease duration of 3.5 +/- 1.5 years were studied with DWI. Data were compared with 12 age-matched healthy control subjects. To objectively localize focal changes of structural neuronal integrity without having to make an a priori hypothesis as to its location statistical parametric mapping (SPM) was applied to our DWI study. SPM localized significant increases of diffusivity in the region of both olfactory tracts in patients (P < 0.001). Trace (D) cut-off values for the voxel cluster of the olfactory tracts have been calculated from the subjects entered into SPM and applied to a total of 17 different individuals (9 patients with Parkinson's disease, disease duration 3.1 +/- 1.3 years and 8 age-matched healthy subjects). Out of 17 subjects, 16 subjects, i.e. 94%, were correctly discriminated with a sensitivity of 100% and a specificity of 88%. All patients with Parkinson's disease were correctly classified and only one normal subject was classified as having the disease, underlining the high potential of this method to separate patients with the illness from healthy subjects. Increased diffusivity in the olfactory tract is in line with the well-established clinical finding of hyposmia in Parkinson's disease. Whether DWI can be used as a marker to identify individuals at risk to develop this disease remains to be shown.

Case-Control Studies↗

Primary angiosarcoma of the breast associated Kasabach-Merritt syndrome during pregnancy.

Primary angiosarcoma of the breast is a rare aggressive tumour of unknown etiology. A frequent clinical presentation is a painful palpable smooth mass or diffuse enlargement of the breast without a palpable mass but with purple discolouration of the overlying skin with apparent bruising. An uncommon clinical presentation of an angiosarcoma is spontaneous bleeding due to disseminated intravascular coagulation (DIC) by consumption coagulopathy, known as the Kasabach-Merritt syndrome. Imaging characteristics of a breast angiosarcoma are limited to a few radiological reports. We report a case of a young pregnant woman with a bleeding angiosarcoma of the breast and associated Kasabach-Merritt syndrome and describe the sonographic and MRI findings.

Adult↗

Transjugular intrahepatic portosystemic shunts: adjunctive embolotherapy of gastroesophageal collateral vessels in the prevention of variceal rebleeding.

PURPOSE: To prospectively compare rebleeding rates in patients treated with transjugular intrahepatic portosystemic shunt (TIPS) creation alone and those treated with TIPS creation combined with adjunctive embolotherapy of gastroesophageal collateral vessels. MATERIALS AND METHODS: Informed consent and ethics committee approval were obtained. Between November 1991 and November 2002, the authors prospectively followed up 95 consecutive patients (61 men, 34 women; age range, 30-81 years) with variceal bleeding due to cirrhosis and portal hypertension. The patients were divided into two groups on the basis of splenoportographic findings after TIPS creation. The patients were treated with TIPS alone (group 1, 42 patients) or in combination with variceal embolotherapy (group 2, 53 patients). Embolotherapy with sclerosing agents in combination with coils was performed when varices continued to fill and the pressure gradient was more than 12 mm Hg. Rebleeding was defined as any hemorrhage necessitating a transfusion of 2 or more units of blood. Estimates for the cumulative patency, survival, and rebleeding rates were calculated by using life-table analysis; the log-rank test was used to compare the two treatment modalities. The prognostic relevance of treatment and selected variables with respect to rebleeding and survival were analyzed with multiple logistic regression. RESULTS: Mean follow-up time (+/- standard deviation) was 48.7 months +/- 37.8 (range, 1-127 months). The proportion of patients (Kaplan-Meier estimation) with TIPS who remained free of bleeding was 61% after 2 years and 53% after 4 years. Patients who underwent both the TIPS procedure and embolotherapy remained free of bleeding in 84% of cases after 2 years and in 81% of cases after 4 years. With respect to the rebleeding rate, the difference between the groups was statistically significant (log-rank test, P = .02). Results of multiple logistic regression analysis showed that variceal embolotherapy significantly reduced the risk of rebleeding (Wald test, P < .001). CONCLUSION: The results suggest that TIPS and adjunctive embolotherapy of gastroesophageal collateral vessels significantly lower the rebleeding rate in comparison to TIPS alone.

Adult↗

Low-profile stent system for treatment of atherosclerotic renal artery stenosis: the GREAT trial.

PURPOSE: The Palmaz Genesis Peripheral Stainless Steel Balloon Expandable Stent in Renal Artery Treatment (GREAT) Trial was designed to assess the safety and performance of a low-profile stent for the treatment of obstructive renal artery disease by looking at 6-month renal artery patency uniformly analyzed by a Core Lab. MATERIALS AND METHODS: Fifty-two consecutive patients (mean age, 63.7 years) were successfully treated with the Palmaz Genesis Peripheral Stent (Cordis, Miami, FL) on the Slalom 0.018-inch Delivery System (Cordis Europe N.V., Oosteinde 8, NLO-9301 LJ Roden, The Netherlands) at 11 investigational centers. Patients with severe renal failure and > 8-mm renal artery were excluded. Primary endpoint was angiographic determination of in-stent percent diameter stenosis at 6 months. Fifty-one patients were treated with one stent, one patient was treated with two stents to cover the complete lesion. RESULTS: Mean percentage diameter stenosis before renal angioplasty was 68.2% +/- 12.0%. No stent implantation failure, displacement, need for additional stent implantation, or procedural complication was observed. Six-month angiography was performed in 41 of 52 patients (79%) resulting in a mean in-stent percent diameter stenosis or Quantitative Vessel analysis (QVA) at 6 months of 23.9%. The in-stent binary (percent diameter stenosis > 50%) restenosis rate at 6 months was 14.3%. No fatal events occurred up to 6 months after implantation. Major adverse events occurred in five patients: four patients (7.7%) required a revascularization and one patient (1.9%) experienced a cerebrovascular event, which regressed spontaneously. CONCLUSIONS: The Palmaz Genesis stent (Cordis) provides good results for renal artery stent placement, with an in-stent binary restenosis rate (percent diameter stenosis > 50%) at 6 months of 14.3% as determined with angiography.

Aged↗

Metallic stents for treatment of benign biliary obstruction: a long-term study comparing different stents.

PURPOSE: To investigate the role of metallic stents in the treatment of benign biliary strictures and analyze the differences in primary patency associated with the various types of stents deployed. MATERIALS AND METHODS: Between 1990 and 1997, 21 patients with benign obstructive jaundice were treated with transhepatic placement of metallic stents (11 Wallstents in 10 patients, nine Palmaz stents in seven patients, and four tantalum Strecker stents in four patients). Nineteen patients presented with strictures not responding to balloon angioplasty (postsurgical, n = 13; cholangitis, n = 5; unknown, n = 1). Estimates for cumulative patency, patency rate in the different stent groups, and survival were calculated with use of life-table analysis; the log-rank test was used to compare the different stent groups. The prognostic relevance of the selected variables-stent type, stent length, etiology, and location-were modeled with respect to patency according to Weibull distribution. RESULTS: The median follow-up time was 80.5 months (range, 2-116 months). The median survival time was 91 months. One patient was lost to follow-up after 3 months. Repeat intervention for recurrent obstructive jaundice was necessary in 11 patients (55%), and the median patency rate was 26 months (range, 2-96 months). The Palmaz stent was the most effective in achieving long-term patency, with a median patency duration of 36 months (range, 22-96 months), versus 9 months (range, 3-67 months) for the Wallstent and 6 months (range, 2-15 months) for the tantalum Strecker stent. The cumulative patency rate with the Palmaz stent was significantly higher than for the tantalum Strecker stent (log-rank test, P = .017) and nonsignificantly higher compared with the Wallstent (log-rank test, P = .07). Multivariate analysis showed that the type of stent (Wald test, P = .003) and stent length (Wald test, P < .0001) influenced the patency rate. CONCLUSIONS: These results suggest that the type of stent and the stent length have a significant influence on the patency rate. In this series, the Palmaz stent was most effective in achieving long-term patency in benign biliary strictures.

Adult↗

In vitro accuracy of a novel registration and targeting technique for image-guided template production.

OBJECTIVES: The objective of this study was to evaluate the accuracy of a novel registration and targeting technique for image-guided template production (IGTP) in a preliminary phantom study. MATERIAL AND METHODS: Registration of four standard dental stone casts with integrated target pellets to the corresponding computed tomography (CT) data was performed via a vacuum mouthpiece and an external reference frame (Medical Intelligence GmbH, Germany). Using the Treon navigation system (Medtronic Inc., Minneapolis, MN, USA) a surgical path with the entry in the centre of the dental crown and the target in the centre of the target pellet was planned on the CT data. An aiming device was adjusted according to the planned trajectory and guided drillings into the dental stone casts. The accuracy was evaluated on postoperative 3D-CT data. RESULTS: The mean fiducial registration error as given by the registration software was 0.4 mm. One hundred and twelve navigated drillings showed a mean accuracy [xy] of 0.42+/-0.26 mm (maximum 1 mm). For the z-axis, a mean accuracy [z] of 0.25+/-0.12 mm (maximum 0.6 mm) was found. CONCLUSIONS: Comparing the presented registration technique to existing registration methods in IGTP and burr tracking, no radiographic and registration templates are needed. The procedure is easy and requires only minimal effort. Navigation-controlled drillings could be performed with an accuracy that approaches the intrinsic navigation system's accuracy, a fact that warrants its use for surgical template production. Further accuracy studies of template-guided drillings are necessary before the presented registration technique can be implemented for patient treatment.

Calcium Sulfate↗

Type A dissection following endovascular thoracic aortic stent-graft repair.

PURPOSE: To describe our experience with endovascular stent-graft repairs in the thoracic aorta focusing on the secondary complication of type A dissection. METHODS: Between January 1996 and April 2004, 73 patients were treated for traumatic thoracic aortic rupture (n=15), type B dissection (n=22), or atherosclerotic descending thoracic aortic aneurysms (TAA, n=36). A retrospective review of the records found 5 (6.8%) patients (3 men; median age 64 years, range 43-87) who experienced a type A dissection at a median 20 days (range 2-124) after thoracic stent-graft repair for 3 type B dissections, 1 TAA, and a late type I endoleak that appeared 28 months after initial stent-graft repair of a traumatic dissection. RESULTS: In 3 patients (2 dissections, 1 endoleak), a tear in the aortic wall at the proximal stent-graft was responsible for a retrograde type A dissection. Underlying disease was the cause of the type A dissection in the 2 other patients (1 dissection, 1 TAA) and was unrelated to the stent-grafts. Three patients underwent open surgery at 3, 26, and 124 days after stent-graft placement; 2 procedures were successful, but the third patient died 3 months later due to multiorgan failure. Two type A dissections were untreated: one patient died from cardiac tamponade 14 days after successful stent-graft exclusion of the type I endoleak; the other patient refused further treatment and survived. The procedure-related mortality following acute retrograde type A dissection was 40%. CONCLUSIONS: Endovascular stent-graft repair of the thoracic aorta is associated with lower morbidity and mortality rates than surgical repair, although potentially lethal complications, acute or delayed, may occur.

Adult↗

Does stent overlap influence the patency rate of aortoiliac kissing stents?

PURPOSE: To determine if the position of kissing stents in the distal aorta has any influence on the patency rate. METHODS: A retrospective review was conducted of 41 patients (22 men; median age 60.8 years, range 44-86) electively treated for atherosclerotic aortoiliac occlusive disease with angioplasty and kissing stents between January 1997 and January 2005. Two patient groups were defined by reviewing postinterventional anteroposterior radiograms: (1) patients in whom the proximal end of the kissing stents overlapped more than half of their angiographic width within the aorta ("crossing" group) and (2) patients in whom the proximal ends of the stents overlapped half of their width or less ("non-crossing" group). RESULTS: At 2 years, the primary and assisted primary patency rates by life-table analysis were 60.8% and 69.4%, respectively, for the 35 patients included in the life-table analysis. There was no significant difference between the 16-patient "crossing" group and the 19-patient "non-crossing" group in terms of the baseline demographic, morphological, and procedural variables. The primary and assisted primary patency rates at 2 years for the "non-crossing" group were significantly higher (94.1% and 100%, respectively) compared to 33.2% and 45.3%, respectively, for the "crossing" group (p=0.01). CONCLUSIONS: Failure of kissing stents in the aortic bifurcation may be significantly increased by the overlap of the free proximal stent ends in the distal aorta.

Adult↗

Dialysis-related amyloidosis revisited.

OBJECTIVE: Dialysis-related amyloidosis occurs secondarily to the deposition of beta(2)-microglobulin. Dialysis-related amyloidosis predominantly involves the osteoarticular system and is clinically manifested by erosive and destructive osteoarthropathies, destructive spondyloarthropathy, and carpal tunnel syndrome. This article illustrates the radiographic, sonographic, CT, and MRI findings of dialysis-related amyloid arthropathies. CONCLUSION: Dialysis-related amyloidosis is characterized by various imaging appearances. In evaluating amyloidosis, MRI provides considerably more information than that obtained from conventional radiographic, CT, and sonographic studies.

Amyloidosis↗

Abdominal aortic aneurysms: virtual imaging and analysis through a remote web server.

The study describes the application of a web-based software in the planning of the endovascular treatment of abdominal aortic aneurysms (AAA). The software has been developed in the framework of a 2-year research project called Aneurysm QUAntification Through an Internet Collaborative System (AQUATICS); it allows to manage remotely Virtual Reality Modeling Language (VRML) models of the abdominal aorta, derived from multirow computed tomography angiography (CTA) data sets, and to obtain measurements of diameters, angles and centerline lengths. To test the reliability of measurements, two radiologists performed a detailed analysis of multiple 3D models generated from a synthetic phantom, mimicking an AAA. The system was tested on 30 patients with AAA; CTA data sets were mailed and the time required for segmentation and measurement were collected for each case. The Bland-Altman plot analysis showed that the mean intra- and inter-observer differences in measures on phantoms were clinically acceptable. The mean time required for segmentation was 1 h (range 45-120 min). The mean time required for measurements on the web was 7 min (range 4-11 min). The AQUATICS web server may provide a rapid, standardized and accurate tool for the evaluation of AAA prior to the endovascular treatment.

Angiography↗

Percutaneous management of a hepatic artery aneurysm: bleeding after liver transplantation.

In this article we present an unusual case of hepatic artery aneurysm bleeding due to a hepatic artery thrombosis after liver transplantation. The patient developed a recurrent hepatic artery thrombosis leading to severe graft failure in four consecutive liver transplantations. While being evaluated for a fifth transplant, stabilization of the clinical situation was attempted by interventional therapy. The first intervention was to place a stent into the hepatic artery to prevent further ischemic damage. This failed to improve graft function, but unfortunately led to the development of a pseudoaneurysm at the distal end with a subsequent rupture into the biliary tree. Bleeding was treated successfully by direct puncture and coil embolization of the aneurysm. In addition, the patient demonstrated a hemodynamically relevant portal vein stenosis on the CT scan. Stenting of the portal vein markedly improved graft function. After extensive investigations, a paroxysmal nocturnal hemoglobinuria was found to be the underlying cause of the recurrent hepatic artery thrombosis. Here we suggest that hepatic artery aneurysm bleeding is a rare but potentially fatal complication that can be successfully treated by percutaneous coil embolization. Additionally, we propose that stenting of the portal vein can lead to a significant improvement of the graft perfusion even though the hepatic artery remained occluded.

Adult↗

Comparison of diffusion-weighted imaging and [123I]IBZM-SPECT for the differentiation of patients with the Parkinson variant of multiple system atrophy from those with Parkinson's disease.

Both dopamine D2 receptor (D2R) binding single-photon emission computed tomography (SPECT) with [123I]iodobenzamide (IBZM) and diffusion-weighted imaging (DWI) have been shown to contribute to the differential diagnosis of patients with the Parkinson variant of multiple system atrophy (MSA-P) and Parkinson's disease (PD). We aimed to compare these two routinely available functional imaging modalities in differentiating patients with MSA-P from PD. For this purpose, results obtained by DWI and IBZM-SPECT were intraindividually compared in a cross-sectional study of 15 MSA-P and 17 PD patients matched for age and disease duration. The activity ratios of striatal to frontal cortex uptake (S/FC ratio) were used as a semiquantitative measure of the relative density of basal ganglia dopamine receptors labeled by IBZM. Regional apparent diffusion coefficients (rADC) were determined in the striatum. MSA-P patients had significantly lower S/FC ratios and significantly higher striatal rADCs than both PD patients and healthy volunteers. There were no significant differences in S/FC ratios and striatal rADC between PD patients and healthy volunteers. Sensitivity of IBZM-SPECT versus DWI for the differentiation of MSA-P from PD was 80% versus 93%, specificity 71% versus 100%, the predictive accuracy 75% versus 97%, the positive predictive value 71% versus 100%, and the negative predictive value 80% versus 94%. Striatal rADCs had a significant higher overall predictive accuracy than D2R binding with IBZM. In summary, our data suggest that DWI may be more accurate compared to IBZM-SPECT in the differential diagnosis of MSA-P versus PD.

Basal Ganglia↗

Trace of diffusion tensor differentiates the Parkinson variant of multiple system atrophy and Parkinson's disease.

We have recently shown that diffusion-weighted magnetic resonance (MR) imaging (DWI) discriminates patients with the Parkinson variant of multiple system atrophy (MSA-P) from those with Parkinson's disease (PD) by regional apparent diffusion coefficients (rADC) in the putamen. Because rADCs measured in one direction may underestimate diffusion-related pathologic processes, we investigated the diffusivity in different brain areas by trace of diffusion tensor (Trace(D)) in a new cohort of patients with MSA-P and PD. We studied 11 MSA-P, 17 PD patients, and 10 healthy volunteers matched for age and disease duration. Regional ADCs in three orthogonal directions and Trace(D) values were determined in selected brain regions including the basal ganglia, gray matter, white matter, substantia nigra, and pons. MSA-P patients had significantly higher putaminal and pallidal rTrace(D) values as well as rADCs in y- and z-direction than both PD patients and healthy volunteers. Moreover, putaminal Trace(D) discriminated completely MSA-P from both PD and healthy volunteers. The rADCs in the y- and z-direction provided a complete or near complete separation. In conclusion, our study confirms the results of previous studies of our group that patients with MSA-P show an increased putaminal diffusivity due to neuronal loss and gliosis. Because rADCs in one direction are dependent on the slice orientation relative to the directions of fiber tracts, Trace(D) imaging appears to be more accurate in the separation of MSA-P from PD.

Aged↗

Endothelin-receptor antagonist treatment of portopulmonary hypertension.

BACKGROUND & AIMS: Portal hypertension leading to variceal bleeding and ascites is a severe complication of liver cirrhosis and is associated with a high mortality rate. Endogenous vasoconstrictors including endothelin might play a role in control of intrahepatic vascular tone. Few patients develop pulmonary hypertension in the setting of portal hypertension, known as portopulmonary hypertension. METHODS/RESULTS: In this case report, we describe a patient with portopulmonary hypertension in the setting of cryptogenic liver cirrhosis. The patient received the dual antagonist of receptors A and B of endothelin-1 bosentan. After 16 and 31 weeks the pulmonary arterial pressure dropped significantly from the baseline value of 88 mm Hg to 63 and 58 mm Hg, respectively. Hepatic venous portal gradient was measured before and after bosentan treatment. Hepatic venous portal gradient significantly decreased from 26 mm Hg (baseline) to 7 and 17 mm Hg at 16 and 31 weeks after treatment with bosentan, respectively. CONCLUSIONS: The present report demonstrates the efficacy of bosentan in the treatment of portopulmonary and portal hypertension in the clinical setting. There are ongoing prospective studies to confirm these data.

Antihypertensive Agents↗

Posttraumatic splenic artery aneurysm presenting as occult gastrointestinal bleeding.

A 53-year-old man presented with a 19-month history of gastrointestinal bleeding. Repeated endoscopic investigation of the upper and lower intestine showed no source of bleeding. When the patient collapsed due to massive gastrointestinal hemorrhage he was referred to our center. Gastroscopy showed a large, bulging tumor protruding from the posterior gastric wall. The consistency of this tumor was soft and the overlying mucosa appeared smooth and intact. Endoscopic ultrasound and contrast-enhanced computerized tomography scan identified a partly thrombosized splenic artery aneurysm (SAA). Arteriography of the celiac trunk confirmed the SAA diagnosis; the SAA was subsequently occluded by coils. So far, four months after discharge, the patient is in excellent health and no further episode of gastrointestinal bleeding has occurred. SAA is a very rare cause of upper gastrointestinal bleeding, but it must be considered when no other common bleeding source can be detected.

Accidents, Traffic↗

Detection of a silent myocardial infarction with phosphor-31 two-dimensional chemical shift imaging (31P 2-D CSI).

BACKGROUND: Phosphor-31 two-dimensional chemical shift imaging (3lP 2-D CSI) is a well-established noninvasive technique in experimental research on regional myocardial ischemia, and it permits in vivo monitoring of high-energy phosphate metabolism in the myocardium without requiring external tracers,wherein phosphocreatinine (PCr) and beta-adenosine triphosphate (beta-ATP) are the main components of investigation. The decrease of PCr is one of the earliest reactions to acute myocardial ischemia, but also fixed defects after myocardial infarction (MI) showed a reduced ratio of PCr/beta-ATP, probably because of are modeling process taking place in the noninfarcted tissue. CASE REPORT: A 55-year-old patient with diabetes mellitus type 1 is reported, who presented within the scope of a study at the University Hospital Innsbruck, Austria, and in whom 31P 2-D CSI helped to detect a so far unknown coronary heart disease (CHD). CONCLUSION: In the presented case, 31P 2-D CSI for the first time helped to reveal a severe CHD and a so far unknown MI,and and if the calculated voxel size was chosen small enough, even a satisfying localization of the lesion became possible.

Adenosine Triphosphate↗