Transitional progressive multiple sclerosis: MRI and MTI findings

Transitional progressive multiple sclerosis (MS) is quite an unusual form of presentation and course of the disease. A case with this progressive form is presented and brain MRI and MTI findings are discussed in relation to the possible insight they may provide for understanding the mechanisms that determine progressive disability in MS.     

Temporal lobe epilepsy with varying severity: MRI study of 222 patients

MRI was performed in 222 consecutive adult patients with temporal lobe epilepsy of varying severity from January 1991 to May 1993. The diagnosis of hippocampal sclerosis was established visually by three independent observers. The accuracy of visual assessment of hippocampal asymmetry was compared with volumetric measurements. Neuropathological correlations were obtained in 63 patients with refractory seizures. Temporal lobe abnormalities were observed in 180 patients (81 %) as follows: hippocampal sclerosis in 122 (55 %); developmental abnormalities in 16 (7.2 %); tumours in 15 (6.8 %); scars in 11 (5 %); cavernous angiomas in 10 (4.5 %); miscellaneous lesions in 6. MRI was normal or showed unrelated changes in 42 patients (19 %). Visual assessment correctly lateralised hippocampal sclerosis in 79 of the 84 patients measured (94 %). Temporal lobectomy confirmed the MRI data (side and aetiology) in all 63 operated patients. Patients with normal MRI had an older age of seizure onset and were more often drug-responsive than patients with hippocampal sclerosis. MRI showed temporal lobe abnormalities in 81 % of epileptic patients with varying severity with good neuropathological correlation. Patients with normal MRI had a less severe form of the disease. Received: 19 August 1996 Accepted: 13 November 1996     

Quantitative analysis of the tomographic technetium-99m MIBI (99mTc-MIBI) myocardial bullseye display: Application to diagnosis of coronary artery disease

Summary In this study, the^99mTc-MIBI myocardial bullseye display of 31 healthy persons and 34 patients with myocardial ischemia and 17 patients with myocardial infarction were analyzed quantitatively, and compared with the results of myocardial tomography analysis and qualitative bullseye analysis. The sensitivities of the three methods were 88.2%, 91.2% and 94.1% respectively (P>0.05), and the specificities were 93.5%, 83, 9% and 83.9% respectively (P<0.05). On the other hand, the quantitative analysis obviously outperformed the other two methods in the detection of ischemic segments of myocardhum near infarction zone (P<0.01). The quantitative analysis of^99mTc-MLBI myocardial bullseye (quantitative bullseye) was an objective, specific and sensitive method for diagnosis of coronary artery disease.     

胼胝体发育不全的MRI表现

对６例胼胝体发育不全的ＭＲＩ表现进行了分析。矢位像可清楚显示胼胝体的形态学变化，冠位或矢位像较轴拉像更易确认三脑室的移位。ＭＲＩ的多方向成像和高组织分辩率较ＣＴ更有利于对胼胝体发育不全及所合并的其他中枢神经系统异常的诊断，故可做为首选的影像学检查方法。     

The somatotopic localisation of the descending cortical tract in the cerebral peduncle: a study using MRI of changes following Wallerian degeneration in the cerebral peduncle after a supratentorial vascular lesion

We studied the effects of Wallerian degeneration in the cerebral peduncle shown by magnetic resonance imaging (MRI) following a supratentorial vascular lesion, to identify the somatotopic localisation of the descending cortical tracts. Patients with a lesion involving a large area of a cerebral hemisphere had an area of abnormal signal intensity in the whole cerebral peduncle, suggesting Wallerian degeneration of all the whole descending cortical tracts. With a small lesion confined to the precentral gyrus, corona radiata, or posterior limb of the internal capsule there was an abnormal signal at the centre of the peduncle, suggesting degeneration of the precentrospinal tract. Those with a small lesion confined to the paracentral gyrus had an abnormal area slightly lateral to the centre of the peduncle, suggesting degeneration of the parietospinal tract. Patients with a lesion of the parietal or temporal lobes, not including the paracentral or precentral gyri, corona radiata, or the posterior limb of the internal capsule, had an abnormal area laterally in the peduncle, suggesting degeneration of the parietopontine or temporopontine tract.     

乳腺占位病变的高场强MRI诊断价值

目的 :总结乳腺良恶性占位病变在高场强MRI的影像表现 ,评价高场强MRI对乳腺良恶性病变的诊断价值。方法 :搜集1996～ 2 0 0 4年间经手术病理证实的 4 3例乳腺良恶性占位病变的MRI资料 ,分析其影像表现。结果 :典型乳腺良、恶性病变 ,高场强MR平扫即能准确诊断 ,而部分非典型良、恶性病灶 ,增强扫描形态、信号变化也有一定的重叠。结论 :MRI技术能够充分显示病变形态及与周围组织结构之间的关系 ,是建议活检或预防性手术的最有力的依据。但是 ,MRI平扫、增强技术对乳腺非典型病变 ,仍然有局限性     

MRI同层动态增强对垂体微腺瘤的诊断价值

目的：分析垂体微腺瘤的MPd同层动态增强特征。方法：对40例临床怀疑为垂体微腺瘤的病人行同层动态增强MPd扫描，并绘出时间一信号强度曲线图。结果：40例病人中共检出垂体微腺瘤26例。同层动态增强后垂体微腺瘤的MPd表现为圆或椭圆形的低或稍低信号，似“充盈缺损”；垂体微腺瘤的最大信号强度多出现在注入造影剂后32～96s，以64s最明显。结论：同层MPd动态增强对垂体微腺瘤的诊断有较高价值。     

原发性骶骨肿瘤病理及影像学表现

目的:分析原发性骶骨肿瘤的病理学分型及影像学表现特点。方法:48例原发性骶骨肿瘤均经手术病理证实,术前均行常规X线平片、CT和/或MR检查,结合病理回顾分析了其影像学表现。结果:原发性骶骨肿瘤以脊索瘤(21例)最多见,其次是巨细胞瘤(7例)、神经源性肿瘤(6例)、软骨肉瘤(4例)、滑膜肉瘤(3例),囊肿(3例),其它相对少见,包括纤维组织细胞癌1例,尤文氏肉瘤1例,梭形细胞癌1例,节细胞神经瘤1例。影像表现包括软组织肿块、骶孔扩大、瘤灶内钙化、骨嵴形成等不同特点。常见原发骶骨肿瘤常有其特征性影像学表现。结论:原发骶骨肿瘤病理分型相对复杂,影像表现多样化,诊断常需综合不同影像检查手段。     

The composite N1 component to gaps in noise.

OBJECTIVE: To indicate whether the double peaked N(1) to gaps in continuous white noise is a composite of onset and offset responses to transients or whether it reflects higher processing such as change or mismatch detection and to assess the role of attention in this process. METHODS: Evoked potentials were recorded to two binaural stimulus types: (1) gaps of different durations randomly distributed in continuous white noise; and (2) click pairs at intervals identical to those between gap onsets and offsets in the continuous noise stimulus. Potentials to these stimuli were recorded while subjects read a text and while detecting gaps in noise or click pairs. RESULTS: Potentials were detected to all click pairs and to gaps of 5 ms or longer, corresponding to the subjects' psychoacoustic gap detection threshold. With long gap durations of 200-800 ms, distinct potentials to gap onset and gap offset were observed. The waveforms to all click pairs and to offsets of long gaps were similar and single-peaked, while potentials to gaps of 10 ms and longer, and potentials to onsets of long gaps were double-peaked, consisting of two N(1) negativities, 60 ms apart, irrespective of gap duration. The first (N(1a)), was more frontal in its distribution and similar to that of clicks. The second (N(1b)) peak's distribution was more central/temporal and its source locations and time course of activity were distinct. No effects of attention on any of the varieties and constituents of N(1) were observed. CONCLUSIONS: Comparing potentials to gap onsets, to click pairs and to gap offsets, suggests that potentials to gap onsets involve not only sound onset/offset responses (N(1), N(1a)) but also the subsequent pre-attentive perception of the cessation of an ongoing sound (N(1b)). We propose that N(1b) is distinct from change or mismatch detection and is associated with termination of an ongoing continuous stimulus. We propose to call it the N(egation)-process. SIGNIFICANCE: A constituent of the N(1) complex is shown to be associated with the pre-attentive perception of termination of an ongoing stimulus and to have distinct scalp distribution and intracranial sources.     

99Tcm标记人源化抗人血小板膜糖蛋白Ⅲ a单克隆抗体SZ21F(ab)2血栓栓塞显像

目的用动物血栓栓塞模型显像评估99^Tc^m标记人源化抗人血小板膜糖蛋白（GP）Ⅲa单克隆抗体（简称单抗）F（ab）2片段SZ21F（ab）2的应用价值。方法通过体外抑制二磷酸腺苷（ADP）诱导的犬血小板聚集实验，评估SZ21F（ab）2与血小板结合的亲和性和特异性。以2-亚氨基噻吩盐酸盐（IT）法修饰SZ21F（ab）2分子的亚氨基，以99^Tc^m-葡庚糖酸钠（GH）转换络合法进行标记。分别用快速薄层层析（ITLC）法和ELISA测定标记物的放化纯及生物活性。对3条肺动脉血栓和8条（包括上述3条）后肢深静脉血栓栓塞比格犬模型进行显像研究。结果SZ21F（ab）2抑制ADP诱导的犬富含血小板血浆（PRP）聚集实验的半数有效剂量（IC50）为（2．49±1．88）μg／ml。ITLC法测得标记物的放化纯为90％～95％，ELISA测定结果表明标记后抗体保留了免疫活性。注射显像剂后1h，肺动脉血栓部位和后肢深静脉血栓部位均出现放射性浓聚。注射后3h，在体显像肺动脉血栓和后肢深静脉血栓栓塞模型的放射性靶／本底（T／B）比值分别为3．03±1．18和3．51±0.62。肺动脉血栓部位和后肢深静脉血栓部位的每克组织百分注射剂量率（％ID／g）分别为0．083％ID／g和0．076％ID／g。体外检测结果表明：肺动脉血栓与正常肺组织的单位质量放射性比值平均为12．8，后肢深静脉血栓与血液的单位质量放射性比值平均为5．2，与肌肉的比值平均为127.0。结论99^Tc^m-SZ21F（ab）2与人血小板具有较高的亲和力，有潜在的血栓显像应用前景。