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T Gasser

Publications and source records attributed to T Gasser.

At least 37 records · Page 2Linked to original sources
PubMed2005

Surgical treatment of intramedullary spinal cord metastases of systemic cancer: functional outcome and prognosis.

OBJECTIVE: Intramedullary spinal cord metastases (ISCM) of systemic cancer are rare. To date, patients with ISCM tend to benefit only to a limited extend from surgery and adjuvant therapy. Subject of this investigation is to assess predictive factors for surgical outcome and survival and to evaluate the value of surgical radicality in the treatment of ISCM. PATIENTS AND METHODS: Between 1990 and 2004, a series of 146 patients with intramedullary tumors underwent surgical treatment in our institution. Among these, 13 patients with intramedullary cancer metastases (7 adenocarcinomas, 3 poorly differentiated carcinomas, 3 sarcomas) were identified. Standard microsurgical removal of the ISCM was performed. Functional outcome was graded according to a standardized scale and factors influencing outcome and survival were statistically analyzed. RESULTS: Median progression-free survival was 13 weeks and median overall survival was 31 weeks. In 5 patients (38) the intramedullary lesion was the initial manifestation of the malignant disease. All poorly differentiated carcinomas and all sarcomas were resected incompletely. Surgical radicality presented a negative predictive factor for functional outcome, increasing radicality leading to functional deterioration. Age, sex, tumor localization, surgical radicality and the presence of neoplastic meningeosis did not affect survival. CONCLUSION: Surgery of ISCM can be performed with an acceptable operative morbidity. Radicality depended on tumor histology. However, radical tumor removal did not affect survival and was correlated with a poor functional outcome. Therefore, complete surgical removal of ISCM should only be intended in patients in whom an unproblematic excision is feasible.

Adenocarcinoma↗
PubMed2005

Functional outcome after surgical treatment of intramedullary spinal cord tumors: experience with 78 patients.

OBJECTIVE: To analyze factors with impact on the functional outcome for patients with surgically treated intramedullary spinal cord tumors (IMSCT) and to point out characteristics of the different histological entities. SETTING: Neurosurgical Department, University of Essen, Germany. METHODS: Between 1990 and 2000, a consecutive series of 78 patients were referred to our institution and underwent surgical treatment. There were 46 (59%) male and 32 (41%) female patients. Mean age was 43.3 years. Functional outcome was analyzed depending on histological features, age, tumor localization and the extension of involved spinal segments. The mean follow-up period was 34.4 months. Operative removal of the IMSCT was performed under standard microsurgical conditions with intraoperative monitoring of somatosensory-evoked potentials (SSEP). RESULTS: The most frequently involved localization was the cervical and cervicothoracic region (55%) followed by the thoracic region (32%) and the medullar conus (13%). The most frequent IMSCTs were neuroepithelial tumors in 44 patients (56.5%) including 32 patients with ependymomas, 15 astrocytomas, and two lesions without further histological classification. Non-neuroepithelial tumors included 10 metastases, nine cavernomas, eight hemangioblastomas, one dermoidal cyst and one enterogenetic cyst. Complete tumor removal was achieved in 65 cases (83.3%) and subtotal resection in nine cases. In four cases a biopsy was performed only. The overall postoperative neurological state was improved or unchanged in 51 patients (65.4%) and worsened in 27 patients (34.6%). A favorable functional outcome was observed in 94.1% of patients with vascular tumors, in 61.3% of patients with low-grade neuroepithelial tumors and in 53.3% of patients with malignant tumors. CONCLUSIONS: The strongest predicting factor of functional outcome was the preoperative neurological condition beyond the histological differentiation of the IMSCT. Although there was no outcome difference with respect to the age and tumor extension, thoracically located IMSCTs proved to harbor an increased risk of postoperative surgical morbidity.

Adolescent↗
PubMed2005

Endovascularly or surgically treated vertebral artery and posterior inferior cerebellar artery aneurysms: clinical analysis and results.

OBJECTIVE: To describe the clinical results in patients with aneurysms of the vertebral artery and posterior inferior cerebellar artery complex (VA-PICA) treated by endovascular embolization or surgically in cases considered untreatable by endovascular methods. PATIENTS AND METHODS: During a 5-year-period a total of 28 patients with a VA-PICA complex aneurysm out of 600 patients received definitive treatment, 19 patients by endovascular embolization and 9 patients surgically. Mean age was 54 years (range 9-75 years). Clinical data, intraoperative observations and procedural complications were evaluated. The mean follow-up was 9 months. RESULTS: Hunt-Hess (HH) grades were HH 0-II in 10 patients (35.7 %), HH III in 6 patients (21.4 %) and HH IV + V in 12 patients (42.9 %). Aneurysm size ranged from 2 to 40 mm (mean size 5.5 mm). Aneurysm configuration was saccular 18, fusiform 7 and multilobed 3. Complete occlusion was achieved in all cases. Overall 67.9 % (n = 19) showed a favorable outcome (Glasgow Outcome Score IV + V). Overall procedure-related rate for permanent morbidity and mortality was 3.6 % (n = 1) and 3.6 % (n = 1), respectively. Predictive factors of clinical outcome were the initial clinical HH grade and the Fisher grade. CONCLUSION: Endovascular embolization is an effective method for the treatment of VA-PICA aneurysms. Surgical clipping is still an alternative and should be considered for "uncoilable" lesions. Outcomes showed a close correlation to the initial clinical state and were not dependent on the treatment modality.

Adolescent↗
PubMed2004

The role of alpha-synuclein gene multiplications in early-onset Parkinson's disease and dementia with Lewy bodies.

BACKGROUND: A triplication of the alpha-synuclein gene was found to cause autosomal dominant Lewy body disease in two distinct families. METHOD: We searched for alterations of alpha-synuclein gene dosage and analysed the entire coding region for point mutations in 54 dementia with Lewy body disease (DLB) and in 103 young onset Parkinson's disease (PD) patients from Central Europe. RESULTS: We could not detect any quantitative alterations in the gene dosage of alpha-synuclein. Mutational screening of the entire coding region of alpha-synuclein revealed only one silent mutation V3V (adenine9guanine) in one case. CONCLUSIONS: Thus, this phenomenon appears not to be a major cause in the pathogenesis of sporadic DLB and young onset PD in this European population.

Adult↗
PubMed2004

Variability of familial hemiplegic migraine with novel A1A2 Na+/K+-ATPase variants.

A1A2 Na+/K+-ATPase mutations cause familial hemiplegic migraine type 2 (FHM2). The authors identified three putative A1A2 mutations (D718N, R763H, P979L) and three that await validation (P796R, E902K, X1021R). Ten to 20% of FHM cases may be FHM2. A1A2 mutations have a penetrance of about 87%. D718N causes frequent, long-lasting HM, and P979L may cause recurrent coma. D718N and P979L may predispose to seizures and mental retardation. A1A2 does not play a major role in sporadic HM; only one variant, R383H, occurred in 1 of 24 cases.

Adolescent↗
PubMed2004

Comparison of alpha-dihydroergocryptine and levodopa monotherapy in Parkinson's disease: assessment of changes in DAT binding with [123I]IPT SPECT.

Putative neurotoxic actions of levodopa and neuroprotective effects of dopamine agonists, as indicated by laboratory and animal studies, provide the rationale to study their effect on the progression of Parkinson's disease. Aim of this pilot study was to compare the effects of monotherapy with the dopamine agonist alpha-dihydroergocryptine (DEC) versus monotherapy with levodopa on nigrostriatal dopaminergic neurons as measured with dopamine transporter (DAT) SPECT. 25 PD patients (H&Y stages 1 to 2.5) entered this study and were treated in a randomized fashion either with DEC (101+/-39 mg) or levodopa (369+/-51 mg) monotherapy. 16/25 patients (8 per group) terminated the study after 52 weeks. In each patient SPECT investigations with [123I]IPT were performed at baseline and after 52 weeks to assess changes of specific DAT binding over time. Changes in clinical symptoms were assessed by UPDRS score. The mean annual decline rate in striatal IPT-binding was lower in the DEC group (8.4%) compared to the levodopa group (10.4%). The difference was most accentuated in the putamen (DEC: 7.3%; levodopa: 16.2%; p = 0.16). Due to the small sample size and the relatively short observation period, however, group differences did not reach a statistical significant level. The results of this pilot study suggest that as compared to levodopa monotherapy DEC may have beneficial effects on decline of dopamine transporter binding similar to those recently described for pramipexole.

Adolescent↗
PubMed2004

Autosomal dominant parkinsonism associated with variable synuclein and tau pathology.

Since the original 1995 report of a parkinsonian kindred, four individuals have been affected (mean age at onset, 65 years). All four had cardinal signs of Parkinson disease (PD) and good response to levodopa. Four autopsies showed neuronal loss and gliosis in the substantia nigra. Lewy bodies (LB) limited to brainstem nuclei were detected in one case, diffuse LB in the second, neurofibrillary tangles (NFT) without LB in the third, and neither NFT nor LB in the fourth. Genetic studies suggested linkage to the PARK8 locus on chromosome 12.

Aged↗
PubMed2004

[The 80 W potassium-titanium-phosphate (KTP) laser vaporization of the prostate. Technique and 6 month follow-up after 70 procedures].

BACKGROUND: Despite good efficacy, even in our days, TURP remains a potentially difficult procedure to perform and is associated with significant risks for the patient. Several alternatives have been tried to reduce the known perioperative morbidity. We report our first experiences with 80 W potassium titanyl phosphate (KTP) laser vaporization of the prostate in patients with symptomatic BPH. PATIENTS AND METHODS: In 70 patients 80 W KTP laser vaporization was performed successfully. Mean age was 70.5 years (46-93 years) and mean transrectal prostate volume was 48.1 ml (10-250 ml). RESULTS: Mean operating time was 41 min ( n=22), 64 min ( n=33), and 80 min ( n=15) for a 26 ml, 46 ml, and a 91 ml prostate, respectively. At time of discharge, after 1 month, and 6 months the urinary peak flow increased by 75.4%, 166.8%, and 168.6%, respectively. CONCLUSION: The 80 W KTP laser vaporization of the prostate combines the tissue-debulking properties of transurethral resection of the prostate with the known good hemostatic properties of other laser procedures. It is a safe procedure for the patient and provides a virtually bloodless operation and immediate improvement of voiding.

Aged↗
PubMed2004

Does intraoperative aneurysm rupture influence outcome? Analysis of 169 patients.

OBJECTIVES: The aim of this study was to evaluate the prognostic value of intraoperative aneurysm rupture (IAR) in patients with subarachnoid hemorrhage (SAH) undergoing surgery for cerebral aneurysms. PATIENTS AND METHODS: Between July 1997 and April 2000, 292 consecutive patients were admitted to our institution with SAH due to ruptured intracranial aneurysms. Of these, 169 patients were treated surgically according to standard microsurgical procedures and were included in this study. Mean age was 47 years. Initial clinical state was graded according to the classification of Hunt and Hess (HH). Outcome was classified according to the Glasgow Outcome Scale as favorable (grades IV and V) and unfavorable (grades I-III). Outcome of patients with intraoperative ruptured and non-ruptured aneurysms was analyzed in correlation to the preoperative clinical state and with respect to the time of surgery and to aneurysm localization. RESULTS: Different rupture rates were observed with respect to the localization of the aneurysm: anterior circulation (n=69) 39.1%, middle cerebral artery (n=46) 34.8%, internal carotid artery (n=48) 31.2%, and posterior circulation (n=6) 16.7%. Patients with HH-grades I-III showed a favorable outcome in 72.2% (61 of 84 patients) without intraoperative rupture and in 71.7% (33 of 46 patients) with intraoperative aneurysm rupture. The corresponding values for patients with HH-grades IV/V were: favorable outcome in 34.6% (9 of 26 patients) and 23.1% (3 of 13 patients), respectively. Poor initial clinical condition (HH IV and V) as well as the initial Fisher grades III and IV were strongly associated with poor clinical outcome. CONCLUSIONS: Intraoperative aneurysm rupture has no impact on the outcome, neither in patients with good initial condition nor for poor grades patients.

Adolescent↗
PubMed2004

Retroperitoneoscopic pyeloplasty for ureteropelvic junction obstruction.

BACKGROUND AND PURPOSE: Retroperitoneoscopy is an established procedure for renal surgery. We evaluated our results with retroperitoneoscopic pyeloplasty for ureteropelvic junction (UPJ) obstruction. PATIENTS AND METHODS: In 14 female and 10 male patients, a retroperitoneoscopic pyeloplasty was performed (13 right/11 left). Four patients had previously had an endopyelotomy. The operation was performed using standard retroperitoneoscopic technique with the patient in a flank position. After preparation of the ureter and renal pelvis, the UPJ was resected in 22 patients in an Anderson-Hynes pyeloplasty. Twenty of these patients had a crossing vessel. The other two patients, who had small renal pelves, were operated on with a Fenger pyeloplasty. In all patients a 7F double-J stent was placed. RESULTS: The mean operative time was 189 minutes (range 70-360 minutes), and the average blood loss was 110 mL (range 50-400 mL). There were no intraoperative complications, although one patient with adhesions and scarring after previous endopyelotomy had to be converted to open surgery. The transurethral catheter was left for 7 days in the first 10 cases and for 4 days in the 14 subsequent patients. The hospitalization time was 9.7 and 7.5 days, respectively. The only postoperative complication was a urinoma, which was punctured. The double-J catheter was removed after an average of 4.6 weeks (range 4-8 weeks). Intravenous urography 6 weeks later showed no obstruction. The mean follow-up time was 11.5 months (range 1-24 months) with no signs of obstruction on ultrasonography. CONCLUSIONS: Retroperitoneoscopic pyeloplasty for UPJ obstruction is a safe and effective procedure. Our short-term results are similar to those of open pyeloplasty with the advantage of a minimally invasive approach.

Adolescent↗
PubMed2004

Cross sectional study of automated blood pressure measurements throughout pregnancy.

OBJECTIVE: To generate reliable new reference ranges for pregnancy blood pressure from a large population. DESIGN: A prospective cross sectional study. SETTING: Obstetric outpatient clinic, Zurich University Hospital. SAMPLE: Accurately dateable singleton pregnancies (Caucasian: n= 3234; Asian [predominantly from Sri Lanka, Thailand and the Philippines]: n= 577; Black n= 212). METHODS: Between January 1996 and February 2000 blood pressure was determined in 4023 pregnant women using an oscillometric automated device (Dinamap) according to British Hypertension Society recommendations. Women receiving antihypertensive medication were excluded. MAIN OUTCOME MEASURE: Blood pressure. RESULTS: Only the means of duplicate measures at the booking visit (5-42 weeks) were used in the analysis. Mean blood pressure decreased from early to mid pregnancy before increasing to levels 4 mmHg higher at term than in early pregnancy. Values >130/80 and <90/50 mmHg were above the 95th and below the 5th centiles, respectively. Parity, age and body mass index were significant determinants in Caucasians. Blood pressure was slightly lower in Asians and Blacks. CONCLUSIONS: The current World Health Organisation definition of high diastolic blood pressure (>or=90 mmHg on two occasions) reflects values >2 standard deviations from the mean. This may be too conservative as threshold for detecting women at risk of pre-eclampsia. Further studies are required to determine the prognostic implications of gestational values >or=95th centile (>or=130/80 mmHg) and <or=5th centile (<or=90/50 mmHg).

Adult↗
PubMed2004

Genome-wide scan linkage analysis for Parkinson's disease: the European genetic study of Parkinson's disease.

OBJECTIVE: To undertake a full genome-wide screen for Parkinson's disease susceptibility loci. METHODS: A genome-wide linkage study was undertaken in 227 affected sibling pairs from 199 pedigrees with Parkinson's disease. The pedigree sample consisted of 188 pedigrees from five European countries, and 11 from the USA. Individuals were genotyped for 391 microsatellite markers at approximately 10 cM intervals throughout the genome. Multipoint model-free affected sibling pair linkage analyses were carried out using the MLS (maximum LOD score) test. RESULTS: There were six chromosomal regions with maximum MLS peaks of 1 or greater (pointwise p<0.018). Four of these chromosomal regions appear to be newly identified regions, and the highest MLS values were obtained on chromosomes 11q (MLS = 1.60, at 91 cM, D11S4175) and 7p (MLS = 1.51, at 5 cM, D7S531). The remaining two MLS peaks, on 2p11-q12 and 5q23, are consistent with excess sharing in regions reported by other studies. The highest MLS peak was observed on chromosome 2p11-q12 (MLS = 2.04, between markers D2S2216 and D2S160), within a relatively short distance (approximately 17 cM) from the PARK3 region. Although a stronger support of linkage to this region was observed in the late age of onset subgroup of families, these differences were not significant. The peak on 5q23 (MLS = 1.05, at 130 cM, D5S471) coincides with the region identified by three other genome scans. All peak locations fell within a 10 cM distance. CONCLUSIONS: These stratified linkage analyses suggest linkage heterogeneity within the sample across the 2p11-q12 and 5q23 regions, with these two regions contributing independently to Parkinson's disease susceptibility.

Adult↗
PubMed2003

Candidate gene studies in focal dystonia.

BACKGROUND: Genetic susceptibility factors for focal idiopathic torsion dystonia (F-ITD) are not established. Mutations in the DYT1 gene can cause focal dystonia, and an association with a polymorphism in the D5 receptor gene (DRD5) has been reported but not confirmed. OBJECTIVE: To investigate a possible role of DYT1 polymorphisms, a CA repeat in the D5 receptor gene (DRD5), the human leukocyte antigen (HLA)-DRB locus, and four polymorphisms in the homocysteine metabolism in the pathogenesis of F-ITD. METHODS: Initially, 100 German patients and 100 matched control subjects were investigated. A second French population with 121 F-ITD patients and matched control subjects was also studied. RESULTS: Two polymorphisms of the beta-cystathionine synthase gene were associated with F-ITD in the German population, but this finding was not replicated in a second independent F-ITD patient and control group of French origin. None of the other investigated polymorphisms was associated with F-ITD. The authors failed to confirm a previously reported association with a polymorphism in DRD5. CONCLUSION: No evidence for an involvement of DYT1, DRD5, HLA-DRB, or polymorphisms in the homocysteine pathway in the pathogenesis of F-ITD was found.

5-Methyltetrahydrofolate-Homocysteine S-Methyltran↗
PubMed2003

L -dopa-induced adverse effects in PD and dopamine transporter gene polymorphism.

OBJECTIVE: To assess whether polymorphisms in the dopamine receptor genes and in the dopamine transporter gene (DAT ) are predictors of adverse effects of L -dopa. METHODS: A retrospective noninterventional study with 183 patients with PD was conducted. Nine polymorphisms of the dopamine D2 receptor (DRD2 ), two of the dopamine D3 receptor (DRD3 ), three of the dopamine D4 receptor (DRD4 ), and one variable number of tandem repeats (VNTR) of the DAT were studied. The entire coding and promoter regions of the DRD2 gene of 48 patients with early and severe appearance of adverse effects from L -dopa treatment and of eight never-afflicted patients were sequenced. RESULTS: The polymorphisms of DRD2, DRD3, and DRD4 were not associated with the risk to develop adverse effects of L -dopa. However, patients with psychosis or dyskinesia carried the nine copy allele 40-bp VNTR of the DAT more frequently than nonafflicted patients (60.0 vs 36.8%, p = 0.008; and 54.7 vs 32.9%, p = 0.006). Sequencing of the DRD2 gene revealed no new mutation, with the exception of one silent mutation in exon 6. CONCLUSIONS: Genetic variations of the DRD2, DRD3, and DRD4 do not influence the occurrence of L -dopa-induced adverse effects. However, the nine copy allele 40-bp VNTR of the DAT is a predictor for the occurrence of psychosis or dyskinesia in L -dopa-treated patients.

Aged↗
PubMed2003

Cross-modal plasticity for sensory and motor activation patterns in blind subjects.

Experimental data on cortical reorganization in blind subjects using H(2)(15)O positron emission tomography and functional magnetic resonance imaging (fMRI) showed activation of the visual cortex related to Braille reading and tactile discrimination tasks in congenitally and early blind subjects. The purpose of our study was to differentiate whether occipital activation of blind subjects during Braille reading is task specific or only triggered by sensory or motor area activation. Twelve congenitally and early-onset blind subjects were studied with fMRI during Braille reading, discriminating nonsense dots, sensory stimulation with electromagnetic pulses, and finger tapping. All experiments were performed utilizing a block design with 6 active epochs alternating with 6 rest conditions lasting 34 s each. Echo-planar imaging sequences with 34 transversal slices were performed on a 1.5-T MR scanner. All blind individuals reading Braille and discriminating nonsense dots showed robust activation of the primary, secondary, and higher visual cortex. Application of peripheral electrical stimuli to the reading hand revealed expected sensory activation of the primary somatosensory cortex, but no activation in the visual cortex. Pure motor activation during finger tapping with the reading hand showed expected precentral activation and no activation of visual cortex. In conclusion, occipital activation during Braille reading and discrimination tasks is not due to plasticity of sensory or motor function; pure motor or sensory tasks do not lead to an activation of striate cortex. The brain learns to differentiate between "finger touching" and "finger reading." Our results suggest that activation of the visual cortex in blind subjects is related to higher and more complex brain functions.

Adult↗
PubMed2002

The prevalence of primary dystonia in the general community.

The prevalence of primary dystonia was assessed in a random population sample of individuals aged 50 and over in Bruneck, South Tyrol. The diagnosis of primary dystonia was confirmed by videotaped review. Primary dystonia was present in 6 of 707 cases resulting in a prevalence rate of 732 per 100,000 (95% CI 319-1,564) in the general population aged 50 and over. Only two cases (33%) had been previously diagnosed. These results indicate that the true prevalence of primary dystonia is significantly higher than published rates.

Adult↗
PubMed2002

PARK6 is a common cause of familial parkinsonism.

The Parkin gene is responsible for about 50% of autosomal recessive juvenile parkinsonism (ARJP) and less than 20% of sporadic early onset cases. We recently mapped a novel ARJP locus (PARK6) on chromosome 1p. Linkage to PARK6 was confirmed in 8 families from 4 different European countries. These families share some clinical features with the European Parkin-positive cases, with a wide range of ages at onset and slow progression. However, features typical of ARJP, such as dystonia and sleep benefit, were not observed, making the clinical presentation of late-onset cases indistinguishable from that of idiopathic PD. The determination of the smallest region of homozygosity in one consanguineous family allowed reducing the candidate interval to 9 cM. PARK6 appears to be an important locus for ARJP in Europe.

Chromosomes, Human, Pair 1↗