A long-term ecstasy-related change in visual perception

Rationale The present study provides the first evidence of the long-term consequences of ecstasy use on visual processes thought to reflect serotonergic functions in the occipital lobe. Methylenedioxymethamphetamine (“ecstasy”) is known to cause lasting changes to the serotonin system in animals, and convergent evidence suggests that similar changes occur in human ecstasy users. Other research suggests that serotonin may be involved in lateral inhibition between orientation sensitive neurons in the occipital lobe, and that disruption to the serotonin system causes an increase in the magnitude of the tilt aftereffect illusion that is known depend on those neurons. Objectives The aim of the present study was to determine if ecstasy users have detectable changes in occipital lobe behavioural functioning, as revealed by the tilt aftereffect illusion. Materials and methods Thirty ecstasy users and 34 non-drug using controls were compared on the magnitude of the tilt aftereffect illusion following adaptation to stimuli oriented at 15 and 40° from vertical. Results Ecstasy users who had not used amphetamines for 115 days or more had a larger average tilt aftereffect than non-drug using controls after adaptation to 40° stimuli but not after adaptation to 15° stimuli. Additionally, there was no difference between non-drug using controls and ecstasy users who had used amphetamines within the last 61 days at either adaptation angle. Conclusions The results were consistent with the proposal that ecstasy-related damage to the serotonin system causes behavioural changes on tests of visual perception processes that are thought to reflect serotonergic functions in the occipital lobe. An erratum to this article can be found at     

A huge occipital osteoblastoma accompanied with aneurysmal bone cyst in the posterior cranial fossa

Osteoblastoma is an infrequent benign tumor and skull involvement is extremely rare. The occipital bone is much less frequently involved. We report an unusual case of a huge occipital osteoblastoma with aneurysmal bone cyst in the posterior cranial fossa of a 20-year-old young man. MRI scan and CT three-dimensional reconstruction revealed that the tumor (approximately 8.5 cm x 6 cm x 5 cm) occupied nearly half volume of the posterior cranial fossa. The cerebellum, the forth ventricle and brain stem were compressed remarkably and hydrocephalus was noted. The tumor mass was multiloculated cystic and highly vascular. Excessive bleeding occurred during operation and total removal was achieved. The patient was symptom-free and MRI scan revealed no evidence of recrudescence after a follow-up period of 18 months. Pathological examination revealed that the lesion was a benign osteoblastoma with secondary aneurysmal bone cyst (ABC). ABC constitutes a highly vascular lesion while complete surgical resection is often impeded by excessive intraoperative bleeding. Preoperative embolization may reduce the risk. Despite the benign nature of osteoblastoma, local recurrence after incomplete resection is not rare and malignant transformation during recurrence may occur even after adequate surgery. Our case confirms the findings of previous investigators that if osteoblastoma is removed completely, no recurrence is expected even without adjuvant irradiation and chemotherapy.     

Childhood occipital epilepsy of Gastaut: a study of 33 patients

PURPOSE: To characterize the electroclinical features and evolution of childhood occipital epilepsy of Gastaut (COE-G). METHODS: Children with electroclinical criteria of COE-G were retrospectively identified and followed-up clinically, and with sleep and awake EEGs between 1990 and 2007. RESULTS: We identified 33 patients with COE-G. In the same length of time, 201 children with Panayiotopoulos syndrome and 410 children with benign childhood epilepsy with centrotemporal spikes were registered. COE-G had a peak age at onset of 8.5 years. Visual manifestations were the most common ictal event. Ictal deviation of the eyes was frequent. Approximately half of the patients had migraine-like symptoms. In all patients the seizures occurred while awake, and 11 also had seizures during sleep. The majority of the patients had occipital spike-wave discharges when the eyes were closed that disappeared or attenuated when the eyes were opened. Prognosis was excellent in 80% of the cases. CONCLUSION: This study confirms the existence of COE-G, a rare but well-defined syndrome within the group of idiopathic focal epilepsies in childhood.     

Familial occipital and nervus intermedius neuralgia in a Swiss family

Familial trigeminal neuralgia has been reported in 1–2% of cases consistent with an autosomal dominant inheritance. We present a Swiss family with several members suffering from occipital and nervus intermedius neuralgia alone or in combination. We suggest that peripheral sensory anastomoses or central convergence of afferent pathways could explain neuralgia affecting two cranial nerves. The pedigree has two main characteristics: (1) affected individuals in two generations and (2) in the first generation the father is affected, in the second generation all women are affected, and none of the men. This is suggestive of an X-linked dominant or an autosomal dominant mode of inheritance.     

Occipital sawtooth: a physiological EEG pattern in very premature infants.

OBJECTIVE: To evaluate EEG maturational features in preterm infants below 27 weeks postmenstrual age. METHODS: EEGs recorded from 5 preterm infants (postmenstrual age 24-26 weeks) were examined and selected maturational features were scored and quantified. The five infants also had serial cranial ultrasound scans (US) and magnetic resonance images of the brain within the first weeks after birth. RESULTS: Background activity was markedly discontinuous in all patients and very variable. Temporal sawtooths occurred but less frequently than in older preterm infants. All 5 infants also showed a particular novel feature, characterized by rhythmic, regularly shaped, medium-high amplitude 4-7 Hz activities, lasting 0.5-3 s and located in the occipital regions. This pattern was symmetrical but sometimes asynchronous. CONCLUSIONS: Occipital sawtooth, so called because it shares shape and frequency with temporal sawtooth but has an occipital localisation, constitutes a physiological EEG pattern characteristic of premature infants between 24 and 26 weeks of postmenstrual age.     

脑后部可逆性脑病综合征的CT、MRI诊断

目的探讨CT、MRI在诊断脑后部可逆性脑病综合征（PRES）中的价值。方法8例女性PRES患者中6例为孕妇，1例肺癌手术后化疗患者，1例高血压患者，均行MR静脉成像（MRV）、T1WI、T2WI、水抑制序列（FLAIR）成像及扩散加权成像（DWI）；其中2例行CT平扫，5例行增强MRI及三维增强MR血管成像（3DCEMRA）。结果CT示病灶呈低密度，边界不清。8例患者MRV显示脑静脉、静脉窦通畅，无狭窄、异常扩张及血栓形成征象。MRI显示双侧顶枕叶（8例）、基底节区（2例）、额叶（4例）多发异常信号，主要位于双侧顶枕叶皮质下白质内，3例患者皮质亦受累。在T1WI病灶呈等或略低信号，T1WI及FLAIR呈高信号，以FLAIR像显示皮质病变为佳。DWI显示大部分病灶呈等信号，表观扩散系数（ADC）图呈等或高信号。部分病灶DWI及ADC图均表现为高信号。随访MRI显示所有患者病灶范围、数目逐渐变小、减少。5例行增强扫描患者显示病灶呈轻度强化，3D CEMRA显示强化沿双侧大脑前动脉、大脑中动脉及大脑后动脉终末支分布，部分呈“葡萄状”。随访增强扫描显示病灶强化范围及程度逐渐缩小、消失。结论FRES好发于顶枕叶白质，但也可见于基底节、额叶及脑皮质。病变为血管源性水肿，增强T1WI及3D CEMRA显示病灶有可逆性强化。以MRFLAIR及T2WI序列显示病灶最佳。     

Clinical and EEG Features of Complex Partial Seizures of Extratemporal Origin

Summary: Complex partial seizures (CPSs) of extratemporal origin are frequently misdiagnosed. Common reasons for diagnostic errors are failure to recognize the epileptic cause of the attacks or to appreciate localizing clinical seizure characteristics and nonspecific or misleading scalp EEG findings. This report describes clinical characteristics of two types of extratemporal CPSs, frontal and occipital. Frontal lobe CPSs are brief, frequent attacks that begin and end suddenly. They are dominated by complex, semi-purposeful motor automatisms, and vocalization and sexual automatisms are common. Their often bizarre appearance frequently leads to a misdiagnosis of hysteria. Occipital lobe CPSs are characterized primarily by their spread pattern, which can follow various paths. They may mimic temporal lobe CPSs, sensorimotor partial seizures, or supplementary motor partial seizures. Scalp EEGs are frequently misleading. The initial clinical symptoms are the most important clue to correct diagnosis and include elemental visual symptoms, visual loss, eye pulling or movement sensations in the absence of detectable movement, rapid forced blinking or eye flutter, and contralateral eye deviation.     

CT-guided chemical rhizotomy of the C1 root for occipital neuralgia

Summary Sensation in the parasagital occipital region is usually provided by fibres from the second cervical root via the greater occipital nerve. In the case presented occipital neuralgia could be relieved only by coagulation of the C1 nerve root with 96% ethyl alcohol. Possible explanations for this observation are discussed and a technique for CT-guided treatment is described.     

The mendosal suture of the occipital bone: occurrence in Indian population,embryology and clinical significance

The Occipital occipital bone is ontogenetically and functionally unique when compared to the other bones of the skull in humans and other mammalian cousins. The Occipital occipital bone develops from six ossification centers; any defect in the ossification process will give rise to mendosal suture (accessory suture) and conditions like posterior plagiocephaly. There is a paucity of literature regarding the mendosal suture and further more, its report in Indian population is not known. The present study was conducted to find out the occurrence of mendosal suture in the Indian dry skulls. Fifteen specimens (3%) were found to have these sutures out of five hundred500 skulls examined. Nine (3.1%) samples are of male skulls out of two hundred ninety (290) and six (2.85%) samples are that of female skulls out of two hundred ten210. The mendosal suture ran close to the superior nuchal line in all specimens and traveled medially from the lambdoidal suture. The length of the sutures ranged from 0.8 cm to 2.6 cm (1.88 cm) on the right side and 1.4 cm to 2.9 cm (1.94 cm) on the left side respectively in male skulls; and 0.7 cm to 2.8 cm (1.55 cm) on the right side and 1 cm to 2.4 cm (1.42 cm) on the left side, respectively, in female skulls. The origin of mendosal suture from the lambdoidal suture was 5.7 cm to –6.3 cm (5.98 cm) from the tip of the mastoid process on the right side and 5.6 to –6.3 cm (6 cm) on the left side, respectively, in male skulls; and 5.4 cm to –5.8 cm (5.58 cm) on the right side and 5.4 cm to –5.6 cm on the left side respectively in female skulls. The occurrence and clinical significance of the present study is discussed.     

海洛因依赖者脑灰质体积的VBM研究

目的探讨海洛因依赖对大脑灰质结构的作用,分析吸食海洛因总时间、吸食海洛因总量、每日吸食海洛因量等因素对脑灰质体积产生的影响。资料与方法采用MRI对17例海洛因依赖者和15名健康受试者行3D结构像扫描,所得数据用基于体素的形态学分析(voxel based morphometry,VBM)方法分析脑灰质体积,并比较两组之间的体积差异;分析脑灰质体积与吸食海洛因总时间、吸食海洛因总量、每日吸食海洛因量之间的相关关系。结果与健康被试者相比,海洛因依赖者右侧眶额回、中央前回、左侧岛叶、扣带回、枕叶舌回灰质体积减少(P<0.005);控制年龄、受教育程度、每日吸烟量后,脑灰质体积变化与使用海洛因总时间、海洛因总量、每日吸食海洛因量之间无显著相关关系。结论长期吸食海洛因导致脑灰质结构损害,主要涉及认知控制、情感、视觉控制等相关脑区。