Morphological analysis of the cervical spinal canal,dural tube and spinal cord in normal individuals using CT myelography

To verify the conventional concept of developmental stenosis of the cervical spinal canal, we performed a morphological analysis of the relations of the cervical spinal canal, dural tube and spinal cord in normal individuals. The sagittal diameter, area and circularity of the three structures, and the dispersion of each parameter, were examined on axial sections of CT myelograms of 36 normal subjects. The spinal canal was narrowest at C4, followed by C5, while the spinal cord was largest at C4/5. The area and circularity of the cervical spinal cord were not significantly correlated with any parameter of the spinal canal nor with the sagittal diameter and area of the dural tube at any level examined, and the spinal cord showed less individual variation than the bony canal. Compression of the spinal cord might be expected whenever the sagittal diameter of the spinal canal is below the lower limit of normal, that is about 12 mm on plain radiographs. Thus, we concluded that the concept of developmental stenosis of the cervical spinal canal was reasonable and acceptable.     

An Organotypic Spinal Cord - Dorsal Root Ganglion - Skeletal Muscle Coculture of Embryonic Rat. II. Functional Evidence for the Formation of Spinal Reflex Arcs In Vitro

Electrical properties of motoneurons, muscle fibres and dorsal root ganglion (DRG) cells were studied in an organotypic coculture of embryonic rat spinal cord, dorsal root ganglia and skeletal muscle. The motoneurons were identified by their morphology and position in culture. Their size and input conductance were significantly larger than those of spinal interneurons. Intracellular current injection evoked action potentials in all motoneurons, but only evoked stable repetitive firing patterns in some. Excitability was correlated to somatic size and the rate of spontaneous excitatory input. It is suggested that the somatic growth and the increase in excitability is regulated by the excitatory afferents. The motoneurons showed spontaneous excitatory and inhibitory postsynaptic potentials and action potentials which disappeared with the application of various agents known to inhibit excitability or excitatory synaptic transmission. Excitatory and inhibitory postsynaptic potentials (EPSPs and IPSPs respectively) were distinguished by their shape, reversal potential and pharmacology. IPSPs could be depolarizing or hyperpolarizing in different cells. A higher percentage of cells with hyperpolarizing IPSPs was found in older cultures and in the presence of skeletal muscle, suggesting a reversal of the polarity of IPSPs with development. The spontaneous muscle contractions observed in the cultures could be due either to innervation, spontaneous oscillations of the membrane potential, or electrical coupling between neighbouring fibres. A small percentage of DRG cells showed spontaneous action potentials, all of which were found in cultures with spontaneous muscle contractions. The electrical stimulation of DRG afferents evoked mono- and polysynaptic EPSPs in motoneurons, endplate potentials and muscle contractions. The stimulation of the ventral horns evoked endplate potentials and muscle contractions via mono- or polysynaptic pathways. Together these results indicate that appropriate and functional contacts were established in the culture between myotubes and DRG cells, between DRG cells and motoneurons, and between motoneurons and muscle fibres.     

Hyperdense middle cerebral artery CT sign

Summary The early CT finding of an hyperdensity of a portion of the middle cerebral artery Hyperdense Middle Cerebral Artery Sign (HMCAS), in patients with supratentorial stroke, is often indicative of an embolic occlusion. Aim of this study was to verify the incidence and reliability of the HMCAS and its possible correlation with early CT findings and with the extent of late brain damage. We studied 36 patients presenting with symptoms of stroke in the MCA territory, by means of CT and angiography performed respectively within 4 and 6 hours. Follow-up CT scans were then obtained after one week and three months from the ischemic event. The HMCAS was present in 50% of our patients and in this group it always correlated positively with the angiographic finding of occlusion. The same group presented a high incidence of erly CT hypodensity (88%). Finally the presence of HMCAS might be considered a negative prognostic sign for the development of extensive brain damage.     

Factors influencing the development of periventricular lucencies in patients with raised intracranial pressure

Summary Sixty patients with raised intracranial pressure and lowered attenuation areas around the lateral ventricles (periventricular lucency, PVL) on CT scanning were reviewed, and compared with a control group of 90 similar patients who did not have PVL. It was confirmed that PVL tends to occur in patients with acute or subacute obstructive hydrocephalus due to a tumour, and is more common in the presence of papilloedema and/or a decreased level of consciousness. Patients with very dilated lateral ventricles did not in general have PVL, but it was frequently seen in association with diastasis of the sutures. Twelve patients with PVL had no other clinical or radiological indication of raised intracranial pressure. Comparison with the control cases did not reveal any reason as to why some patients should develop PVL while others did not.     

CT对腹部创伤的诊断价值

目的 探讨CT对腹部创伤的诊断价值。方法 应用CT扫描对38例腹部外伤病人进行检查。结果 CT扫描诊断肾外伤12例，肝外伤5例，肠系膜血肿1例，肠穿孔2例，脾外伤18例，其中有7例为复合伤。CT扫描能清楚地显示脏器损伤及腹膜出血的程度、范围。结论 CT能快速、准确地检出腹腔脏器损伤的程度，为临床选择治疗方法提供重要依据。     

茎突CT薄层冠状扫描在诊断茎突过长综合征中的价值

目的 探讨“一点一线垂直法”茎突CT薄层冠状扫描在诊断茎突过长中的价值。方法测量72例双侧茎突的长度、方位、形态、厚度、尖端与咽侧壁距离,总结茎突过长病人的临床症状与诊断。 结果 ①41例67侧长度超过3.0cm,符合茎突过长的诊断;②12例12侧茎突虽未超过3.0cm(均在2.5～2.9cm),且茎突方位角>20°、末端与咽侧壁的距离<20mm,并有临床症状的应考虑茎突过长综合征;③按茎突的形态进行分型:锥型(分直锥、弧锥),束状型,分节型,发育不良型。其中分节型与临床症状有密切关系。结论 ①茎突CT薄层冠状扫描能清晰显示茎突的长度、形态、厚度、末端与咽侧壁距离,是诊断茎突过长的一种可靠方法;②“一点一线垂直法”茎突CT薄层冠状扫描无需进行图像重建,可操作性强、简捷易行、便于推广。     

迟发性颅内血肿诊治体会

<正> 迟发性外伤性颅内血肿(DTICH)是指头部外伤后首次头颅CT检查未发现血肿,经过一段时间后再次行CT检查或经手术、尸检发现的血肿;或在初次头颅CT检查证实的在不同部位出现的血肿。其病死率及致死率较高,应予以重视。现将我科收治的11例DTICH患者资料总结如下。     

CT引导下经肋间隙穿刺活检12例临床报告

目的　对 12例患者的CT引导下经肋间隙穿刺活检操作方法和临床价值进行总结。方法　选择 2 0 0 0年 1月至 2 0 0 2年 6月 12例CT引导下经肋间隙穿刺患者 ,并经病理细胞学及组织学证实。结果　所有 12例患者在CT引导下穿刺均获得成功 ,11例取得较满意的细胞学及组织学材料 ;有 1例发生并发症。结论　CT引导下经肋间隙穿刺活检准确率较高 ,并发症较低 ,安全、可靠 ,是一种先进科学的检查方法     

实验性脑脓肿影像学改变的病理基础研究

目的：明确不同时期动物脑脓肿的影像学特征及其相应的病理学改变。方法：制备脑脓肿狗动物模型１４只，采用ＣＴ、ＭＲＩ检查结合多项病理学观测进行动态分析。结果：脑炎期ＭＲＩ对炎症坏死区及水肿范围的显示较ＣＴ扫描更为清晰准确。包膜形成期：ＣＴ上脑脓肿包膜强化是炎症区血脑屏障破坏和新生血管形成所致；ＭＲＩＴ２加权成像上包膜的低信号“暗带”与包膜上的巨噬细胞堆积有关，延迟扫描和ＭＲＩ均能有效地区分脑脓肿的急性脑炎期和包膜形成期，但ＭＲＩ更加准确、迅速。结论：脑脓肿的ＭＲＩ特征与其临床分期及病理学变化的相关性较好，能更加准确、简便、迅速地区别脓肿的脑炎期和包膜形成期，可作为临床诊治脑脓肿的有力参考。