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101.
X-linked deafness,stapes gushers and a distinctive defect of the inner ear   总被引:12,自引:0,他引:12  
Summary The association of X-linked mixed deafness with stapes gusher has been recognised for 20 years, and imaging studies by polytomography have shown dilatation of the lateral end of the internal auditory meatus (IAM) in some cases. We have made genetic linkage studies in 7 pedigrees in whom deafness was inherited in an X-linked manner. All patients had a full range of audiometric and vestibular function tests. Thin section high resolution CT in two planes was used to assess the state of the middle and inner ears. We found a distinctive inner ear deformity in some of the deaf males characterised not only by a wide bulbous IAM but more importantly, by deficient or absent bone between the lateral end of the IAM and the basal turn of the cochlea. We believe that this results in a communication between the subarachnoid space in the IAM and the perilymph in the cochlea, leading to perilymphatic hydrops and a gusher if the stapes is disturbed. Moreover, some of the obligate female carriers seem to have a milder form of the same anomaly associated with slight hearing loss. Genetic studies on some of the deaf males with apparently normal inner ear anatomy suggest a different locus on the X chromosome and hence a different pathogenesis for the deafness.  相似文献   
102.
Primary intracranial arachnoidal cysts   总被引:1,自引:1,他引:0  
Sixty-seven cases (41 males and 26 females) of arachnoidal cysts in children under 11 years are reported. About 53% of cases were diagnosed before 1 year of life. Thirty-one (42.2%) were supratentorial (interhemispheric 9, temporal fossa 10, convexity 5, sylvian fissure 3, supra- and/or retrosellar 4); 31 (46.2%) infratentorial (supra- and/or retrocerebellar 22, foramen of Magendie 3, quadrigeminal cistern 5, pontocerebellar 1); 5 (7.5%) supra-and infratentorial. Macrocephaly was the presenting symptom in 48 cases (71.5%). Associated features were frequent: cranial asymmetry in 24; aqueductal stenosis in 10; agenesis of corpus callosum in 8; deficient cerebellar lobullation in 4; Chiari I malformation in 2; neurofibromatosis type 1 with dysgenetic zones of the brain in 1; arteriovenous malformation in 1. Diagnosis was made at autopsy in six cases in the days before computed tomography and magnetic resonance: three patients had a cyst in the supra-and retrocerebellar midline; two had a cyst in the quadrigeminal cistern and the sixth was a rare case with the cyst passing from the posterior fossa to the left lateral ventricle through a hole in the basal surface of the brain. Small and some middle-sized cysts were not treated. Big and some middle-sized cysts were usually treated by cysto- and/or ventriculoperitoneal shunts. Arachnoidal cysts of the quadrigeminal cistern usually present with aqueductal stenosis and have to be treated with ventriculoperitoneal shunt. Craniotomy and fenestration of the cysts were performed in some cases with good results. The average mental level of these children is usually moderately low.  相似文献   
103.
Thirty-eight cases of Dandy-Walker malformation (DWM) are presented. A female predominance of 3:1 was found. Thirty-two cases (84%) were diagnosed within the 1st year of life. Of these, 17 cases (44.7%) were diagnosed at birth. Ten (26%) were delivered by cesarean section. Thirteen infants (34%) had a birth weight below 3000 g. Several associated malformations were observed, the most frequent being capillary angioma (6 case); cardiac malformations, ophthalmic anomalies, agenesis of the corpus callosum, malformed limbs, and occipital meningocele were also seen. These observations indicate that DWM represents a disorder of the midline central nervous system indicative of marked genetic and etiologic heterogeneity with the possibility of showing clinical and pathological alterations intra-and extracranially. Macrocephaly was the most frequent physical finding, appearing in 31 cases (82%). Seventeen (44.7%) patients died, 11 before 6 months of age, 3 between 6 and 12 months, and 3 after 1 year. Postmortem studies were performed in 13 patients. Three cases have been lost to follow-up. Mental retardation (IQ below 70) was found in 11 cases (58% of survivors), low intellect (IQ between 70 and 85) in 4, and only 2 patients showed normal intellectual development (IQ more than 85). The high incidence of malformations having several genetic and environmental origins, as well as the high early mortality of patients with DWM, indicate the complexity of this syndrome, which involves the midline developmental field structures. It is not an isolated malformation of the posterior fossa in most cases.  相似文献   
104.
永存动脉干病理分型及临床诊断探讨   总被引:4,自引:1,他引:4  
目的 通过临床和心血管造影检查资料分析探讨 39例永存动脉干 (TAC)的病理分型及临床诊断。方法  39例TAC中 ,年龄 8个月至 2 5岁 ,平均 (7 9± 6 0 )岁。每例均经详问病史、常规体检、心电图、X线胸片和二维超声心动图检查及右心室和动脉干造影检查作出TAC的诊断。按Collett和Edwards分型方法分型 ,并结合VanPraagh分型进行讨论。 结果 按Collett和Edwards分型 ,Ⅰ型 4例 ,Ⅱ型 4例 ,Ⅲ型 3例 ,Ⅳ型 2 8例。结论 根据TAC定义 ,结合Tucuer的报道 ,Collett和Edwards分型的Ⅳ型可能为法洛四联症伴肺动脉闭锁 (假性动脉干 ) ,按VanPraagh分型更为合理。体循环侧支造影或电子束CT检查 ,在确定Collett和Edwards分型的Ⅳ型TAC是否为假性动脉干方面有重要价值。  相似文献   
105.
目的:探讨几种内耳畸形患儿的人工耳蜗植入效果。方法:对10例内耳结构异常的感音性耳聋患儿进行了人工耳蜗植入。结果:术后随访0.5~4.0年,10例基本达到了较满意的听觉言语恢复效果。结论:内耳畸形息儿行人工耳蜗植入,应严格进行术前听力学与影像学的评估,严格掌握手术的适应证,可以达到较满意效果。  相似文献   
106.
目的 介绍后颅窝骨性扩大术治疗Chiari畸形合并脊髓空洞症。方法 该手术分为两种亚术式 ,一种是枕颈固定扩大术 :取自体髂骨 5cm× 10cm ,打磨成“凹”字形。上端为齐头端 ,固定在后颅窝减压窗缘。缺口端为下端 ,固定在枢椎棘突上 ,将扩大的硬脑 (脊 )膜修补筋膜片固定在植骨片内面 ,使筋膜片贴附在植骨片内面 ,形成帐篷状 ;另一种是单纯骨性扩大术 :取自体髂骨 6cm× 8cm的梯形骨片 ,并利用较厚的髂骨缘打磨成弧形。植骨片固定在后颅窝减压窗上 ,弧形端构成枕骨大孔后缘。将扩大的硬脑 (脊 )膜修补筋膜片也固定在植骨片内面 ,使筋膜片贴附在植骨片内面 ,也形成帐篷状。结果 本组病例随访 2~ 7年 ,术后症状体征缓解总有效率为91.6% ,肌力比以前提高 2~ 3级。结论 该术式比其他治疗Chiari畸形合并脊髓空洞症的术式 ,治疗效果显著 ,疗效切实可靠  相似文献   
107.
目的探讨不同类型血管瘤、血管畸形和同一类型不同时期的内皮细胞增殖情况及肥大细胞计数的变化。方法采用免疫组织化学方法及细胞特染技术,对120例婴幼儿和28例成人血管瘤标本进行了增殖细胞核抗原(PCNA)检测和肥大细胞计数比较。结果增生期毛细血管瘤、混合型血管瘤PCNA表达为阳性,其他均为阴性。经统计学处理,各类增生期血管瘤PCNA表达阳性率及肥大细胞计数均明显高于消退期婴幼儿血管瘤及各类血管畸形,有显著差异(P<0.01)。结论PCNA的表达对血管瘤和血管畸形的鉴别诊断及治疗选择具有指导意义;血管瘤的内皮细胞增生与肥大细胞增多有密切关系。  相似文献   
108.
PURPOSE: To report a novel malformation in a male subject with refractory partial seizures. METHODS: Magnetic resonance imaging (MRI) and data reformatting in a subject referred for management of partial seizures. RESULTS: The patient had four distinct partial seizure types, without learning disability. MRI demonstrated the novel association of bilateral laminar subcortical heterotopia, bilateral temporal periventricular heterotopia, and hippocampal malformation. CONCLUSIONS: This previously unreported complex bilateral neocortical and archicortical malformation in a male patient cannot be explained by known genetic causes of heterotopia, raising the possibility of a novel gene involved in brain formation.  相似文献   
109.
DNA Fragmentation in Central Nervous System Vascular Malformations   总被引:3,自引:0,他引:3  
Recent studies have shown that apoptosis plays an important role in vascular remodeling. We examined central nervous system vascular malformations for the presence of DNA fragmentation which is the evidence of apoptosis. We hypothesize that vascular remodeling through apoptosis may be responsible for recurrence or hemorrhage in these lesions. We examined the specimens of central nervous system vascular malformations by in situ end labeling (ISEL) of fragmented DNA. Moreover, we examined the expression of Caspase-3 which is apoptosis-related proteins in these lesions by immunohistochemistry. DNA fragmentation was observed in all 15 arteriovenous malformation (AVM) specimens. ISEL-positive cells were mainly distributed in the endothelium, media and perivascular tissue. In cavernous hemangioma (CH), DNA fragmentation was also observed in all 5 specimens. ISEL-positive cells were distributed in the endothelium, subendothelium and intercavernous matrix. Thirteen out of 15 AVM lesions stained positive for Caspase-3. Caspase-3 immunoreactivity was mainly distributed in the endothelium, media and perivascular tissue. This distribution was similar to that of ISEL positive cells. As for CHs, all 5 lesions stained positive for Caspase-3. Caspase-3 immunoreactivity was distributed in the endothelium, subendothelium and intercavernous matrix. Our findings indicate that apoptotic cell death and vascular remodeling play a role in the development and maintenance of vascular malformations.  相似文献   
110.
Surgery for Syringomyelia: An Analysis Based on 163 Surgical Cases   总被引:23,自引:0,他引:23  
Goel A  Desai K 《Acta neurochirurgica》2000,142(3):293-302
Summary ? Object. The authors analyzed the cases of 163 patients with syringomyelia to assess the appropriate surgical procedure. Methods. Depending on the aetiological factors and treatment considerations the series was classified into three groups. Group I were cases where there was no definite demonstrable aetiological factor; Group II cases had basilar invagination and/or Chiari malformation; and Group III consisted of cases where the syrinx was secondary to an obvious aetiology, such as a mass lesion either in the posterior cranial fossa or in the spine or a severe kyphotic spinal deformity. Post-traumatic syringomyelia and syrinx in association with spina bifida were not studied. Conclusions. We concluded that for Group I cases syringosubarachnoid shunting is the ideal form of treatment. In Group II cases foramen magnum bony decompression is satisfactory and physiological. Good results were obtained even in cases where either a foramen magnum decompression alone or in combination with a syringo-subarachnoid shunt was done. Only syringosubarachnoid shunt (without a foramen magnum decompression) in Group II cases was found to produce poor outcome. Group III cases should be treated for the primary aetiological problem. Only syrinx drainage procedure without treatment of aetiology in these cases produced poor results. It was observed that clinical outcome rather than radiological improvement is the reliable indicator of the surgical result.  相似文献   
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