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Franz A Fellner

Publications and source records attributed to Franz A Fellner.

14 recordsLinked to original sources
PubMed2006

Accessory nerve to suprascapular nerve transfer to restore shoulder exorotation in otherwise spontaneously recovered obstetric brachial plexus lesions.

OBJECTIVE: A systematic follow-up of infants with an obstetric brachial plexus lesion of C5 and C6 or the superior trunk showing satisfactory spontaneous recovery of shoulder and arm function except for voluntary shoulder exorotation, who underwent an accessory to suprascapular nerve transfer to improve active shoulder exorotation, to evaluate for functional recovery, and to understand why other superior trunk functions spontaneously recover in contrast with exorotation. METHODS: In 54 children, an accessory to suprascapular nerve transfer was performed as a separate procedure at a mean age of 21.7 months. Follow-up examinations were conducted before and at 4, 8, 12, 24, and 36 months after operation and included scoring of shoulder exorotation and abduction. Intraoperative reactivity of spinatus muscles and additional needle electromyographic responses were registered after electrostimulation of suprascapular nerves. Histological examination of suprascapular nerves was performed. Trophy of spinatus muscles was followed by magnetic resonance imaging scanning. The influence of perinatal variables and results of ancillary investigations on outcome were evaluated. RESULTS: Exorotation improved from 70 degrees to functional levels exceeding 0 degrees, except in two patients. Abduction improved in 27 patients, with results of 90 degrees or more in 49 patients. Electromyography at 4 months did not show signs of denervation in 39 out of 40 patients. Intraoperative electrostimulation of suprascapular nerves elicited spinatus muscle reaction in 44 out of 48 patients. Histology of suprascapular nerves was normal. Preoperative magnetic resonance imaging scans showed only minor wasting of spinatus muscles in contrast with major wasting after successful operations. CONCLUSION: An accessory to suprascapular nerve transfer is effective to restore active exorotation when performed as the primary or a separate secondary procedure in children older than 10 months of age. Contradictory spontaneous recovery of other superior trunk functions and integrity of suprascapular nerves, as well as absence of spinatus muscle wasting direct to central nervous changes are possible main causes for the lack of exorotation.

Accessory Nerve↗
PubMed2005

Thrombolysis beyond the guidelines: two treatments in one subject within 90 hours based on a modified magnetic resonance imaging brain clock concept.

BACKGROUND AND PURPOSE: We report the first case of 2 intravenous thrombolysis treatments within 90 hours in a patient with early recurrent stroke. SUMMARY OF REVIEW: A 50-year-old man had improved significantly after intravenous thrombolysis for acute stroke. On the fourth day, he deteriorated dramatically because of recurrent stroke. Evidence of vessel reocclusion and profound perfusion/diffusion mismatch constituted the rationale for a second thrombolysis treatment, which resulted in vessel recanalization and significant neurologic improvement. CONCLUSIONS: The pathophysiological information obtained by multimodal magnetic resonance imaging may suit as a brain clock when repeat thrombolysis treatment is considered for early recurrent stroke.

Brain↗
PubMed2005

Importance of T2*-weighted gradient-echo MRI for diagnosis of cortical vein thrombosis.

We examined six patients with isolated venous thrombosis (n = 2), or venous thrombosis combined with sinus thrombosis (n = 4) (CVT). The clinical symptoms were non-specific (acute cephalea, paresis, epileptic seizure, progressive speech disorder). All examinations were performed on a 1.5 T system (Magnetom Symphony, Siemens, Erlangen, Germany), maximum gradient field strength 30 mT/m, minimal gradient rise time 450 micros, according to the following protocol: Transverse T2-weighted turbo spin-echo (TSE), fluid attenuated inversion recovery (FLAIR), T1-weighted spin-echo (SE), before and after administration of contrast medium, T2*-weighted conventional gradient-echo (GRE), T2*-weighted spin-echo echo planar imaging (SE EPI), both without and with diffusion weighting as well as two-dimensional (2D) venous time-of-flight (TOF) MRA. The venous thromboses were best detectable in the T2*-weighted conventional GRE sequence in all patients. In two patients, the CVT was discernible only in this sequence. The sinus thrombosis was well discernible only in the T2*-weighted GRE sequence in only one case; in the remaining cases it was detectable only with difficulty. For these cases, other sequences such as SE, diffusion-weighted, or 2D-TOF-MRA sequence were superior. The T2*-weighted conventional GRE sequence was superior to the T2*-weighted SE EPI sequence in all patients. To sum up, it can be concluded, that T2*-weighted conventional GRE sequences are possibly the best method of detection of acute cortical vein thromboses. Therefore, it seems to be of benefit to integrate a T2*-weighted conventional GRE sequence into the MR-protocol for the diagnosis of isolated cortical vein thrombosis.

Adult↗
PubMed2005

Contrast-enhanced MR angiography of peripheral arteries including pedal vessels at 1.0 T: feasibility study with dedicated peripheral angiography coil.

PURPOSE: To prospectively determine feasibility of contrast material-enhanced magnetic resonance (MR) angiography of the peripheral arteries from distal aorta to pedal arteries with a 1.0-T system and a dedicated phased-array coil. MATERIALS AND METHODS: Twenty-seven patients with peripheral arteriosclerotic occlusive disease underwent contrast-enhanced MR angiography with an automatic moving-table technique. In addition, lower-leg and pedal arteries were examined without table movement (hybrid technique). Two radiologists independently reviewed MR angiograms to assess image quality and grade stenosis in 13 segments per leg. Each was blinded to patients' clinical data. Twenty-five of the patients also underwent conventional angiography. Stenosis grade at conventional angiography was assessed by two radiologists in consensus. Interobserver variability for stenosis grade at MR angiography was calculated with Cohen kappa test. Specificity and sensitivity of MR angiography in detection of stenosis of more than 50% and occlusion were calculated for both observers. The study was approved by the local ethics committee. RESULTS: In 14 of the 27 patients, hybrid technique was superior to moving-table technique because there was less venous overlap (11 patients), fewer motion artifacts (one patient), or both (two patients). In nine patients, there was no difference between techniques; in four patients, moving-table technique was superior. Stenosis grade was analyzed in 698 segments with MR angiography and in 638 segments with both conventional and MR angiography. Kappa analysis of interobserver agreement with MR angiography yielded a score of 0.84. For the 638 segments evaluated with both conventional and MR angiography, observers 1 and 2 assigned same grade of stenosis with both modalities in 558 and 555 segments, respectively. Sensitivity for stenoses greater than 50% and occlusion was 94.4% and 91.1% for observers 1 and 2, respectively, and specificity was 90.6% and 91.3%. More distal runoff vessels were shown with MR angiography in seven cases and with conventional angiography in two cases. CONCLUSION: Contrast-enhanced MR angiography of the peripheral vessels with a 1.0-T system and dedicated peripheral angiography coil is feasible, and in some cases, it provides additional information compared with conventional angiography.

Aged↗
PubMed2005

Magnetic resonance angiography of the carotid arteries using three different techniques: accuracy compared with intraarterial x-ray angiography and endarterectomy specimens.

PURPOSE: To compare three different magnetic resonance angiography (MRA) techniques with x-ray angiography and endarterectomy specimens. MATERIALS AND METHODS: Twenty-one patients underwent x-ray angiography, three-dimensional time-of-flight (TOF) focusing on the carotid bifurcation, high-resolution (HR) contrast-enhanced (CE) MRA, and time-resolved CE MRA. Stenoses of internal carotid arteries were evaluated by three independent observers on identical projection of x-ray angiography and MRA. Maximum stenosis grades on MRA were assessed additionally and correlated with endarterectomy specimens in 12 cases. RESULTS: Sensitivity for the detection of severe stenoses was excellent (100%) for all MRA techniques, and specificity was superior for three-dimensional TOF (96.7%) compared with HR CE MRA (80.6%) and time-resolved CE MRA (83.9%). The correlation between x-ray angiography and MRA for all stenoses was slightly superior for three-dimensional TOF and HR CE MRA compared with the time-resolved technique (kappa = 0.87 and 0.86 vs. 0.84). The same trend was seen for the interobserver agreement and for the correlation with endarterectomy specimens. Eleven up to 17 stenoses (depending on the MRA technique) were graded higher using additional projections. CONCLUSION: Three-dimensional TOF MRA yielded even more accurate results than HR CE MRA in grading of stenoses near the carotid bifurcation. Therefore, a combination of both methods seems to be advantageous.

Aged↗
PubMed2005

Cerebral cavernous malformations associated with venous anomalies: surgical considerations.

OBJECTIVE: Once thought to be rare entities, mixed cerebrovascular malformations with pathological features of more than one type of malformation within the same lesion are now being recognized with increasing frequency. Their identification generates several hypotheses about common pathogenesis or causation-evolution among different types of lesions and leads to controversial discussion on therapeutic strategies. METHODS: Fifteen patients drawn from a consecutive series of 58 patients harboring cavernous malformations (25.9%) were found to have an associated venous malformation (VM). Three (33.3%) of the first 9 patients, in whom the large draining vein of the VM had been left untouched at previous interventions, developed recurrent and/or de novo lesions. RESULTS: Histopathological analysis, interestingly, revealed that the new lesions were different in nature (three arteriovenous angiomas in two patients, a capillary telangiectasia in one patient). During extirpation of the new malformation, the draining vein of the VM in these three patients could be coagulated without any adverse events. Coagulation and dissection of the draining vein of the associated VM was performed in six more patients of our series, and this has prevented development of new lesions up to now. CONCLUSION: Our results are in favor of the hypothesis that the draining vein of a VM is the actual underlying abnormality of mixed vascular malformations. Causing flow disturbances and having the potential for hemorrhages, the VM seems to promote the development of new adjacent malformations. Thus, permanent cure of associated malformations might depend on the surgical treatment of the VM. We present a preliminary personal series and a thorough review of the literature.

Adolescent↗
PubMed2004

Implementation of T2*-weighted MR for multimodal image guidance in cerebral cavernomas.

The aim of this study was to evaluate the feasibility, the safety, and the usefulness of T2*-weighted magnetic resonance (MR) for neuronavigational guidance in patients with cerebral cavernomas. Eight patients with intracerebral cavernomas were operated assisted by T2*-weighted MR image-guidance. The cavernomas were either deep-seated or in eloquent regions. Image fusion of a contrast-enhanced T1-weighted gradient-echo (GRE) sequence with a T2*-weighted GRE sequence was performed via an automated fusion software (StealthMerge). The T2*-weighted images were used to secure complete resection of the cavernoma in all patients and to verify resection of surrounding hemosiderin-stained tissue in epilepsy cases. Furthermore, the multimodal neuronavigational concept included ultrasonography, corticography, and evoked potentials. Postoperative MR excluded any residual malformation in all cases. There was no postoperative morbidity; all epilepsy patients are seizure-free up to now. In our preliminary series, T2*-GRE-guided neuronavigation proved useful for resection control in cavernoma surgery, and we suppose that it will be helpful to clarify the discussion on the value of resection of the surrounding hemosiderin-stained tissue.

Adolescent↗
PubMed2003

Peripheral vessels: MR angiography with dedicated phased-array coil with large-field-of-view adapter feasibility study.

At magnetic resonance (MR) angiography with conventional phased-array coils, visualization of the vascular tree from the infrarenal aorta to the pedal arch is not possible in most patients. For this purpose, the authors developed a dedicated adapter with a large field of view that allows coverage of a body length of approximately 1,380 mm. Among five patients with peripheral arteriosclerotic disease, four underwent both conventional angiography and MR angiography. One hundred fourteen vascular segments from the infrarenal aorta to the feet were evaluated. Agreement between findings at conventional angiography and those at MR angiography was 94.7% (108 of 114) for all segments (96.1% [25 of 26] in the abdomen or pelvis, 97.5% [39 of 40] in the thigh, and 91.7% [44 of 48] in the calf or foot).

Aged↗
PubMed2003

Dumbbell-shaped hypoglossal schwannoma. A case report.

Dumbbell-shaped neuromas of the 12th cranial nerve extending intra- and extracranially are extremely rare. The present paper reports on a 32-year-old patient who presented with hypoglossal nerve palsy and a two-year history of headache. MRI showed inhomogeneous contrast agent enhancement in a tumor that was partly cystic, partly solid, in the cerebellopontine cistern. The tumor, with its main lesion mass located in the parapharyngeal space, extended along the canal of the hypoglossal nerve. The tumor was excised by two-stage suboccipital osteoclastic craniotomy and later through a cervical approach. Pathohistology showed a grade I schwannoma and the patient was discharged symptom-free without any further therapy.

Adult↗
PubMed2003

MR diagnosis of superficial femoral artery aneurysm, primarily misdiagnosed as soft tissue tumor. A case report.

We report a 84-year-old man with an aneurysm of the superficial femory artery (SFA). Primarily, after B-mode sonography soft tissue neoplasm was suspected and sectional MR imaging was performed for further diagnostics. Because of blood flow related ghost artifacts, sectional MR led to the diagnosis of an partially thrombosed aneurysm without angiography. Initially, the differential diagnosis of an SFA aneurysm, which is extremely rare, has not been considered. Soft tissue neoplasms may have a similar appearance to partially thrombosed aneurysms. This case demonstrate the importance to notice also artifacts in sectional MRI which can give important informations for correct diagnosis.

Aged↗
PubMed2002

High-resolution, contrast-enhanced magnetic resonance angiography with elliptical centric k-space ordering of supra-aortic arteries compared with selective X-ray angiography.

BACKGROUND AND PURPOSE: The objective of this study was to evaluate the relative value of high-resolution, contrast-enhanced MR angiography (CE MRA) with elliptical centric k-space ordering compared with intra-arterial x-ray angiography for imaging carotid stenosis. METHODS: Thirty patients with suspected stenosis of the carotid arteries were examined with CE MRA (1.5-T scanner) and x-ray angiography (aortic arch survey and selective imaging of both common carotid arteries). For the first time, not only the extracranial carotid bifurcation but all the vessel segments from the aortic arch to the circle of Willis were assessed by independent investigators. RESULTS: For the internal carotid artery in the region of the extracranial carotid bifurcation, there was a very close correlation between CE MRA and x-ray angiography (sensitivity, 100%; specificity, 92%). The initially suspected overestimation of stenosis on CE MRA in 3 cases was ultimately revealed to be an underestimation on x-ray angiography. CE MRA showed slightly poorer imaging of the basal vessel segments at the level of the aortic arch (because of breathing artifacts) and the intracranial vessel segments (because of small vessel caliber and venous superimposition due to delayed sequence starts). CONCLUSIONS: The MRA technique described here provides reliable results in the diagnosis of carotid stenosis and is thus suitable for replacing the invasive conventional x-ray angiography method in most cases. Further technical developments with regard to spatial resolution are still required for improved visualization of small vessels (terminal carotid branches and intracranial vessels).

Aged↗
PubMed2002

The way out.

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Angiography↗
PubMed2002

MR changes after acute cyanide intoxication.

We describe MR changes that occurred 3 and 6 weeks after a suicide attempt with cyanide. The toxicity of cyanide causes damage, primarily to the basal ganglia, and those changes were visible as altered signal intensity on the first MR images. Extensive areas of hemorrhagic necrosis were seen 6 weeks later. Our case shows pseudolaminar necrosis along the central cerebral cortex 3 weeks after cyanide poisoning, showing that the sensorimotor cortex is also a site for toxic necrosis because of its high oxygen dependency.

Adult↗