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101.
Norbert Boos Daniel Dreier Esther Hilfiker Volker Schade Roland Kreis Josef Hora Max Aebi Chris Boesch 《Journal of orthopaedic research》1997,15(1):141-149
The purpose of this investigation was to determine differences in tissue composition of symptomatic and asymptomatic disc herniations as reflected in T1 and T2 relaxation times (quantitative magnetic resonance investigation of the lumber spine. The longitudinal and transverse magnetic rlaxation times (T1 and T2, respectively) were calculated from a set of 20 images obtained with five single-slice/multi-echo sequences at different repetition time values on a commercial whole-body system (1.5 T). Twenty-two symptomatic and asymptomatic disc herniations could be matched according to age, gender, disc level, and the extent of herniation (protrusion or extrusion) and were compared with regard to T1 and T2 relaxation times. Symptomatic disc herniations exhibited significantly (pT1 < 0.04 and pT2 < 0.003) shorter T1(ΔT1:–182.1 milliseconds, ?15%) and T2(ΔT2: ?11.0 milliseconds, ?21%) relaxation times than matched asymptomatic herniations. Symptomatic disc herniations also exhibited more advanced disc degeneration as graded by Pearce's criteria (p < 0.01). These results suggest that symptomatic and morphologically matched asymptomatic disc herniations differ with regard to disc matrix composition. 相似文献
102.
103.
H.-G. Machens P. Brenner H. Wienbergen N. Pallua P. Mailänder A. Berger 《Der Unfallchirurg》1997,100(9):711-714
Summary
Enchondroma are benign cartilaginous tumors and are localized most often at the site of the phalanges. Between 1982 and 1993
73 patients with monostotic enchondroma and 5 patients with polyostotic enchondroma were operated at our clinic. Clinical
signs of monostotic tumors were pathological fracture (38.4 %), pain or swelling. Eleven percent of cases were accidental
findings. Surgical treatment was performed by complete removal of the tumors and filling the bone cavity with autologous spongiosa
taken from the pelvic bones, the elbow, or the radius. Three patients (4.1 %) had to be operated a second time due to wound
infections and hematoma. In one case Sudeck's dystrophy was diagnosed. One patient (1.4 %) developed a recurrent tumor. Our
follow-up examination of 65 patients showed that 77 % of the patients with monostotic enchondroma achieve very good or good
functional long-term results after this operation, but only 40 % of the patients with polyostotic enchondroma.
相似文献
104.
105.
Significance of haemorrhagic lacunes on MRI in patients with hypertensive cerebrovascular disease and intracerebral haemorrhage 总被引:4,自引:1,他引:3
Our purpose was to determine the frequency and signifcance of haemorrhagic lacunes (HL) on MRI in patients with a history of, or at risk for intracerebral haemorrhage. We examined 72 patients with old spontaneous intracerebral haemorrhage (ICH) using T1-and T2-weighted spin-echo sequences. MRI studies of 137 consecutive patients with cerebrovascular disease but no known ICH were also reviewed. Both groups showed about the same degree of age-related white matter change and nonhaemorrhagic lacunar infarcts, whereas the ICH group had a higher frequency of HL (12/72 patients) than the non-ICH group (6/131 patients,p<0.01). These results correlate well with reported pathological findings. We conclude that haemorrhagic lacunes found on MRI studies of patients with cerebrovascular disease may suggest a higher risk of intracerebral haemorrhage. 相似文献
106.
107.
Martin Krause Wolfgang Fogel Volker Tronnier Sabine Pohle Konstanze H?rtnagel Ute Thyen Jens Volkmann 《Movement disorders》2006,21(12):2255-2257
Pantothenate kinase-associated neurodegeneration (PKAN) is a rare autosomal recessive disorder with onset in childhood and rapid progression. There is no causative and insufficient symptomatic drug therapy. Deep brain stimulation (DBS) of the internal pallidum (GPi) has been reported to improve motor function. Most case reports, however, are limited to short observational periods. The impact of DBS on the progression and life expectancy in PKAN is unknown. We present a 5-year outcome and video documentation of bilateral GPi-DBS of an adolescent patient suffering from genetically defined PKAN. 相似文献
108.
Monitoring motor function during resection of tumours in the lower brain stem and fourth ventricle 总被引:4,自引:0,他引:4
Sven Gläsker Ulrich Pechstein Vassilios I. Vougioukas Vera Van Velthoven 《Child's nervous system》2006,22(10):1288-1295
Objectives Even in the days of modern microsurgery, the removal of a brain stem lesion remains a surgical challenge. Especially when operating on children, the prognosis is directly related to the radicality of the resection; however, a radical resection is often associated with surgical morbidity. Intraoperative neuromonitoring could help to minimise the surgical morbidity, but few studies have been performed to clarify the value of this monitoring. We investigated a prospective series of 21 patients with lesions involving the brain stem for the prognostic value and benefits of neuromonitoring.Methods We performed intraoperative neuromonitoring of cranial nerve function by electromyography (EMG) and motor evoked potential (MEP). The results were correlated with postoperative neurological deficits.Conclusions There is a good correlation between intraoperative neurophysiological events and postoperative neurological deficits in patients with lesions of the brain stem. In general, transient, prolonged, spontaneous activity in EMG is associated with a transient paresis of the respective muscle, whereas a permanent spontaneous activity is associated with a permanent deficit. Intraoperative neuromonitoring reliably predicts postoperative neurological function in patients with tumours of the lower brain stem and fourth ventricle. This neuromonitoring guides the neurosurgeon in the operation and may decrease surgical morbidity. We recommend using monitoring of MEP and EMG of the lower cranial nerves in surgery on all patients with lesions involving the lower brain stem and fourth ventricle. 相似文献
109.
Dr. med. Günter Krämer 《Zeitschrift für Epileptologie》2006,19(3):174-175
Ohne Zusammenfassung 相似文献
110.