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951.
Rhombencephalosynapsis is an unusual disorder characterised by maldevelopment of the rhombencephalon, sometimes with supratentorial
midline anomalies. We report MRI findings in a 39-year-old woman, the oldest in the literature. MRI demonstrated hypoplasia
of the cerebellar vermis, with fusion of the cerebellar hemispheres and abnormally oriented folia. Supratentorial anomalies
were also seen.
Received: 26 April 1999 Accepted: 13 July 1999 相似文献
952.
Dural enhancement in pituitary macroadenomas 总被引:1,自引:0,他引:1
We describe the normal dural enhancement patterns of the sellar region and determine whether the duramater is affected by
pituitary macroadenomas. Dural enhancement appeared to be usually abnormal in 20 patients with pituitary macroadenoma compared
with 20 control patients, mainly at the planum sphenoidale and carotid sulcus. However dural changes are subtle and their
recognition requires knowledge of the normal enhancement patterns. Dural changes, reported in a variety of inflammatory and
infectious dural diseases and after surgery, are not specific and may be also seen in pituitary macroadenomas.
Received: 12 December 1998 Accepted: 3 November 1999 相似文献
953.
We report a case of transient neurologic toxicity secondary to tacrolimus. The clinical and imaging findings are reported
and their subsequent regression after interruption of therapy in the patient following a bone-marrow transplant is also described.
The etiology of the neurotoxicity and its analogy with other immunosuppressant agents are discussed.
Received: 18 June 1999/Accepted: 14 December 1999 相似文献
954.
Rathke's cleft cyst associated with hypophysitis: MRI 总被引:6,自引:0,他引:6
955.
Diagnosing CADASIL using MRI: evidence from families with known mutations of Notch 3 gene 总被引:4,自引:1,他引:3
Clinical data and MRI findings are presented on 18 subjects from two families with neuropathologically confirmed CADASIL.
DNA analysis revealed mutations in exon 4 of Notch 3 gene in both families. All family members with mutations in Notch 3 gene
had extensive abnormalities on MRI, principally lesions in the white matter of the frontal lobes and in the external capsules.
Of several family members in whom a diagnosis of CADASIL was suspected on the basis of minor symptoms, one had MRI changes
consistent with CADASIL; none of these cases carried a mutation in the Notch 3 gene. MRI and clinical features that may alert
the radiologist to the diagnosis of CADASIL are reviewed. However, a wide differential diagnosis exists for the MRI appearances
of CADASIL, including multiple sclerosis and small-vessel disease secondary to hypertension. The definitive diagnosis cannot
be made on MRI alone and requires additional evidence, where available, from a positive family history and by screening DNA
for mutations of Notch 3 gene.
Received: 17 February 1999 Accepted: 23 July 1999 相似文献
956.
Cavernous dilatation of mesencephalic Virchow-Robin spaces with obstructive hydrocephalus 总被引:2,自引:1,他引:1
We describe two patients with mild ventricular dilatation, shown to have cystic spaces in the midbrain, which we interpreted
as greatly enlarged Virchow-Robin spaces. We discuss the pathophysiology and the possible relations to the mild hydrocephalus.
Received: 1 September 1999/Accepted: 22 October 1999 相似文献
957.
Contrast enhancement of the cerebrospinal fluid on MRI in two cases of spirochaetal meningitis 总被引:5,自引:0,他引:5
We report two patients with meningitis due to spirochaetal infection, both of whom showed diffusely enhancing meninges around
the brain and spinal cord. In addition, there was enhancement of the cerebrospinal fluid after intravenous administration
of Gd-DTPA.
Received: 1 March 1998/Accepted: 21 August 1999 相似文献
958.
MRI of orbital schwannomas 总被引:5,自引:0,他引:5
The literature on MRI of orbital schwannomas is limited. The appearances in three patients with an orbital schwannoma were
reviewed. A superior orbitotomy through a subfrontal craniotomy revealed a schwannoma in all cases. MRI characteristics of
very low signal on T 1-weighted images and homogeneous postcontrast enhancement may be helpful for differentiating schwannomas
from other intraconal masses.
Received: 21 June 1999/Accepted: 20 September 1999 相似文献
959.
目的 :探讨单光子发射计算机断层(SPECT)脑血流显像在癫灶定位诊断 ,指导癫外科治疗的价值。方法 :对88例难治性癫患者进行了脑电图(EEG) ,磁共振成像(MRI)和SPECT脑血流显像检查 ,其中42例患者进行了外科(开颅手术或γ刀放射)治疗。结果 :SPECT脑血流显像的阳性率最高 ,为90.9 % ,EEG和MRI的阳性率分别为76.1 %和40.9 %。外科治疗患者SPECT与EEG定位结果的一致及相对一致率为83.3 % ,SPECT与MRI定位结果的一致及相对一致率为81.3 %。3者定位结果的一致及相对一致率为75.0 %。外科治疗的有效率为83.3 %。结论 :SPECT脑血流显像是诊断癫灶灵敏而有效的方法 ,对正确选择癫手术或γ刀治疗方案并取得较好的治疗效果具有重要意义 相似文献
960.
迷路纤维化的诊断及人工耳蜗植入3例分析 总被引:3,自引:0,他引:3
目的:探讨迷路纤维化的影像学诊断及对人工耳蜗植入术的效果。方法:结合文献复习,报告3例迷路纤维化患者行人工耳蜗植入术的临床资料。结果:术前CT扫描3例均未发现异常。1例术前MRI提示耳蜗基底间纤维状,1例术后提示对侧耳蜗纤维化。2例病变较轻者成功地进行了人工耳蜗植入术,术后恢复良好;1例因病变严重电极未能植入。结论:MRI在迷路纤维化的诊断中有重要价值。慢性化脓性中耳炎为迷路纤维化的病因之一。慢性化脓性中耳炎一期手术清理中耳病变后,具有进行人工耳蜗植入的可行性。 相似文献