磁共振波谱分析在颞叶癫痫的临床应用价值

目的 评价氢质子磁共振波谱(1HMRS)分析在颞叶癫痫(TLE)病灶术前评定中的价值.方法 对45例手术证实为单侧TLE患者的单体素1HMRS数据进行回顾性分析,并以日常检查中随机的14例健康志愿者为对照,计算代谢产物氮-乙酰天门冬氨酸(NAA)、肌酸(Cr)、胆碱复合物(Cho)、NAA/Cr、NAA/Cho、NAA/(Cr Cho)的值,比较患者病变组与对侧组、病变组与对照组之间有否差异.结果 患者病变组中NAA为(52.31±12.78)ppm,Cr为(40.36±8.06)ppm,Cho为(42.78±10.43)ppm,NAA/Cr为(1.29±0.15),NAA/Cho为(1.24±0.14),NAA/(Cr Cho)为(0.63±0.05),对侧组分别为(58.04±13.25)ppm、(40.49±10.02)ppm、(42.42±10.68)ppm、(1.45±0.16)、(1.39±0.13)、(0.70±0.05);对照组分别为(59.86±11.28)ppm、(39.00±7.10)ppm、(40.43±6.61)ppm、(1.55±0.19)、(1.49±0.12)、(0.76±0.06);病变组NAA、NAA/Cr、NAA/Cho、NAA/(Cr Cho)较对侧组及对照组明显降低(P<0.05);Cr值和Cho值差异不明显(P>0.05),以NAA/(Cr Cho)比值为参考值最可靠(CV在7.04%～7.93%).NAA/(Cr Cho)值取0.65,病变侧与对侧间差值取0.07为标准,对病变定侧诊断的准确率为86.67%,特异性为100%.结论 1HMRS分析能够无创地定量反映颞叶生化代谢异常,是TLE患者术前评价的一种有用的辅助检查方法.     

海马-杏仁核电镜改变与颞叶癫痫的关系

为研究海马 杏仁核的超微结构改变与颞叶癫痫的关系 ,对 35例颞叶癫痫病人行海马 杏仁核切除术 ,并对海马 杏仁核组织进行超微结构分析。痫灶区海马神经元以神经细胞固缩、变性为著 ,并可见有髓纤维的松解和粘连。轴索萌发出的新突出物、微管及微丝在无髓纤维上不规则排列和缠绕。神经毡内突触前终末兴奋性递质小泡增多 ,嵴消失 ,粗面内质网扩张 ,多聚核糖体解聚 ,并可见大量脂褐素及脂滴 ,星形细胞轻度水肿。提示颞叶癫痫发作不仅仅是单纯的生理生化改变所引起暂时性脑功能失调 ,其病理改变在颞叶癫痫的形成和持续状态具有重要的作用     

Pyramidal lobe decreases endogenous TSH stimulation without impact on radio-iodine therapy outcome in patients with differentiated thyroid cancer

Objectives

The aim of the study was to assess the frequency of pyramidal lobe (PL) detected in iodine-131 (I-131) scans of thyroid bed in patients after thyroidectomy for differentiated thyroid cancer (DTC) and to investigate influence of PL on endogenous thyrotropin (TSH) stimulation as well as on the effects of the radio-iodine ablation in one-year follow-up.

Patients and methods

This study was designed as a retrospective analysis of 302 radio-iodine neck scans of patients thyroidectomized due to DTC. The study population was selected from patients with PL detected in thyroid bed scintigraphy. Patients without PL were included to the control group. The study and the control groups did not differ in age, sex of patients, histological type and stage of the DTC.

Results

Pyramidal lobes were found in 30.5% of all patients. Patients in the study group underwent repeat surgery more often than controls without PL. Preablative TSH level in patients with PL was statistically lower than in the control group, in contrast to free thyroid hormones, which were higher in patients with PL. Preablative and postablative TSH-stimulated thyroglobulin (Tg) and antibodies against thyroglobulin (TgAbs) were measured in both groups, and comparison did not reveal differences. Moreover, for the per-patient analysis, sites of uptake in whole body scintigraphy performed 1 year after radio-iodine remnant ablation (RRA) did not differ between the study and the control groups.

Conclusion

Pyramidal lobe decreases endogenous TSH stimulation without impact on radio-iodine therapy outcome in patients with DTC.     

Musical anhedonia: Selective loss of emotional experience in listening to music

Recent case studies have suggested that emotion perception and emotional experience of music have independent cognitive processing. We report a patient who showed selective impairment of emotional experience only in listening to music, that is musical anhednia. A 71-year-old right-handed man developed an infarction in the right parietal lobe. He found himself unable to experience emotion in listening to music, even to which he had listened pleasantly before the illness. In neuropsychological assessments, his intellectual, memory, and constructional abilities were normal. Speech audiometry and recognition of environmental sounds were within normal limits. Neuromusicological assessments revealed no abnormality in the perception of elementary components of music, expression and emotion perception of music. Brain MRI identified the infarct lesion in the right inferior parietal lobule. These findings suggest that emotional experience of music could be selectively impaired without any disturbance of other musical, neuropsychological abilities. The right parietal lobe might participate in emotional experience in listening to music.     

A Mirror in the Mind: A Case of Visual Allaesthesia in Homonymous Hemianopia

We report the case of a 61-year-old female patient with intracranial bleeding in left parietal and parieto-temporal regions and a history of epilepsy and migraine. MR images showed lesions of the optic radiation, but primary visual cortical areas were intact. Perimetric testing revealed an incomplete right hemianopia. The patient claimed that visual percepts from her intact field were projected as “mirror images” into the hemianopic field. The illusory images were weak and sometimes difficult to detect, but focusing spatial attention on the “mirror” image increased its saliency. Drawings the patient made of her pseudo-hallucinations revealed that the illusions were lateral transpositions instead of mirror images of real objects. The illusions were tilted in clockwise direction and were never colored, although color discrimination was unimpaired in the patient's left hemifield. We quantified the characteristics of the pseudohallucinations in several experiments: The patient was asked to adjust the position, rotation angle, and size of a white test card in her blind field so that it corresponded with the illusory projection of a card of standard size and position that was presented in the intact field. The test card was compressed in horizontal size by 20% and positioned 17° visual angle to the right of the standard, shifted 1.5° upward or downward, and rotated in clockwise direction by 22.6° on average. Large objects in the intact field were projected incompletely into the blind area. Our patient's symptoms are similar to those reported in earlier case studies of visual allaesthesia. We hypothesize that the “mirror image” is induced by sparse input from contralesional V1 via the corpus callosum upstream of the lesion site and a lack of inhibition or hyperexcitability of ipsilesional early visual areas after deafferentation. The rotation of the illusions may be induced by the parietal lesions causing faulty co-ordinate computations, e.g., an inability to integrate visual and otholitic input.     

Evidence for a social function of the anterior temporal lobes: Low-frequency rTMS reduces implicit gender stereotypes

By nature, stereotypes require processes of categorization or semantic association, including social information about groups of people. There is empirical evidence that the anterior temporal lobe (ATL) processes domain‐general semantic information, and supports social knowledge. A recent study showed that inhibitory repetitive transcranial magnetic stimulation (rTMS) to the ATL reduced racial stereotypes on an implicit association test (IAT). However, it was not determined whether this was caused by changes to specific social, or general semantic processing, or both. The current study addresses these theoretical issues. The design investigated the effect of rTMS to the left or right ATL, or a sham stimulation, on a social IAT (gender stereotypes), a non-social IAT (living versus non-living associations), and a non-semantic control (Stroop) task. The results showed that low-frequency rTMS to both left and right ATL significantly reduced D-scores on the gender IAT compared to the sham group; however, there were no differences on the non-social IAT or the Stroop. The findings show the ATL has a role in mediating stereotypes, and the decrease of bias after stimulation could be due to weakening of social stereotypical associations either within the ATL or via a network of brain regions connected with the ATL.     

Anatomical variations of donor portal vein in right lobe living donor liver transplantation: the safe use of variant portal veins

In right lobe (RL) living donor liver transplantation (LDLT), portal vein (PV) variations are of immense clinical significance. In this study, we describe in detail our PV reconstruction techniques in RL grafts with variant PV anatomy and evaluate the impact of accompanying biliary variations on the recipient outcomes. In a total of 386 RL LDLTs performed between July 2004 and July 2012, the clinical data on 52 (13%) transplants using RL grafts with variant PV anatomy were retrospectively analyzed. Portal vein anatomy was classified as type 2 in 20 patients, type 3 in 24 patients, and type 4 in eight patients. The PV reconstruction techniques utilized included back‐wall plasty (n = 21), back‐wall plasty with saphenous vein graft interposition (n = 6), saphenous vein graft interposition (n = 5), cryopreserved iliac vein Y‐graft interposition (n = 6), and quiltplasty (n = 3). There was no donor mortality. In a median follow‐up of 29 months, none of the recipients had vascular complications. Anomalous PV anatomy was associated with a high (54%) incidence of biliary variations; however, these variations did not result in increased biliary complication rate. Overall, the 1‐ and 3‐year patient survival rates of recipients were 91% and 81%, respectively. Vascular and biliary variations in RL grafts render LDLT technically more challenging. By employing appropriate reconstruction techniques, it is possible to successfully use RL grafts with PV variations without endangering recipient and donor safety.