Neurosurgical anatomy of the anterior interhemispheric approach for aneurysms of the anterior communicating artery (26.6.92)

Summary The anterior interhemispheric approach for aneurysms of the anterior communicating artery was studied in ten cadavers. This approach presents several advantages over the pterional approach widely used in neurosurgery. It allows direct access to the region of the anterior communicating artery complex with minimal retraction of the brain and preservatioin of the olfactory tract and the gyrus rectus.

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Bases anatomiques de l'abord inter-hémisphérique antérieur lors de la chirurgie des anévrysmes de l'artère communicante antérieure

Résumé Ce travail concerne l'abord neurochirurgical des anévrysmes de l'artére communicante antérieure par voie frontale interhémisphérique. L'étude anatomique a été réalisée sur dix sujets. Cette exposition possède de nombreux avantages comparée à la voie ptérionale habituelle : voie d'abord reduite médiane permettant une visualisation directe et symétrique du complexe artériel de l'artére communicante antérieure ; avec le moindre manipulation et retraction du cerveau en respectant les voies olfactives et le gyrus rectus.

     

Effect of thymosin and B-activin on lateralization of sensomotor control in rats

Research Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR Research Laboratory of Biologically Active Substances of Hydrobionts, Ministry of Health of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR G. N. Kryzhanovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 108, No. 8, pp. 139–142, August, 1989.     

Callosal connections of the parabelt auditory cortex in macaque monkeys

Auditory cortex of macaque monkeys is located on the lower bank of the lateral sulcus and the adjoining superior temporal gyrus. This region of cortex contains a core of primary-like areas surrounded by a narrow belt of associated fields. Adjacent to the lateral belt on the superior temporal gyrus is a parabelt region which contains at least two subdivisions (rostral and caudal). In previous studies we defined the parabelt region as cortex with topographic cortical connections with the belt areas surrounding the core, and connections with the dorsal and magnocellular divisions of the medial geniculate complex, but minimal connections with the core region and ventral division of the medial geniculate complex. The callosal connections of the parabelt auditory cortex were determined by placing injections, of up to six distinguishable tracers, into different locations of the parabelt region in each of four macaque monkeys. The results indicated that the strongest callosal projections arise from homotopic areas in parabelt cortex, and they roughly matched the rostrocaudal levels of the medial and lateral belt cortex. Weaker callosal inputs to the parabelt originate from the corresponding levels of the superior temporal gyrus and superior temporal sulcus. The core region does not contribute significant callosal projections to the parabelt region. The results provide further support for the conclusion that the parabelt region represents a third level of auditory cortical processing beyond direct activation by primary subcortical and cortical auditory structures.     

Aggressive resection of craniopharyngioma achieved by drilling the tuberculum sellae/planum sphenoidale using a frontal basal interhemispheric approach: A review of 55 cases

ObjectiveThe frontal basal interhemispheric approach (FBIA) is preferable for resection of craniopharyngioma (CP), achieving desirable total resection rates in early reports of lesions located in the suprasellar region to the third ventricle. For tumours that have created a larger obstruction of the tuberculum sellae and planum sphenoidale, aggressive resection in the intrasellar region and medial wall of the cavernous sinus is not feasible compared to improving tumour visualization by drilling the tuberculum sellae and planum sphenoidale. In a report of drilling the sellar tuberculum and sphenoid planum, drilling allowed the direct visualization of tumours invading the intrasellar region and medial wall of the cavernous sinus. Reconstructing the opening of the sellar-sphenoid cavity is achieved by microsuturing a piece of the pericranium/dura around the dural edge of the defective dura of the open sphenoid sinus and sellar cavity to prevent cerebrospinal fluid (CSF) leakage.Patients and methodsThe FBIA with drilling of the tuberculum sellae and planum sphenoidale was performed to remove the tumours that invaded the intrasellar region and cavernous sinus in 55 patients from January 2014 to October 2019 at our institution. The pre- and postoperative pituitary hormone levels and vision were evaluated as effective standards after surgery and compared using paired t-tests. The different rates of CSF leakage between the packing and microsuture groups were compared by χ² test, p < 0.05.ResultsIn all patients with a mean 37-month follow-up (range, 3–2 months), 43 (78.2%) patients returned to their normal life or school independently, 7 (12.7%) patients were able to perform normal activities with minor complaints or effort, and 4 (7.3%) patients could care for themselves or only required occasional assistance. One (1.8%) death occurred, attributed to CSF leak-related meningitis at 5 months after surgery. Postoperative CSF leakage occurred in eight (19.0%) of 42 patients with packed bone wax or pieces of muscle to the sphenoid sinus. Of 13 patients with a piece of the periosteum/dura microsutured around the defective dura of the sellar region and open sphenoid sinus, one (7.7%) of 13 patients experienced CSF leakage in the perioperative period. With statistical analysis, there was a potential risk for postoperative CSF leakage in the bone wax and muscle piece in the open sphenoid sinus, whereas microsuture manoeuvres were effective for avoiding the risk of postoperative CSF leakage (χ² = 8.865, p < 0.005). The microsutures closed the open sphenoid sinus such that it was water-tight. Postoperative visual acuity and the visual field were not affected by the increased intrasellar exposure or the open sphenoid sinus achieved by drilling the tuberculum sellae and planum sphenoidale.ConclusionTuberculum sellae/planum sphenoidale drilling via FBIA is feasible to enhance the direct visualization of CP resection, which expands the intrasellar region with a direct resection of recurrent tumours in the sellar cavity and adhering to the medial wall of the cavernous sinus. The potential risk of a CSF leakage seemed to be mitigated when using water-tight microsutures on a piece of the pericranium/dura around the edge of the defective dura in the sellar region and the open sphenoid sinus cavity.     

前纵裂入路显微手术切除鞍上脑室内外型颅咽管瘤

目的 探讨前纵裂入路在鞍上脑室内外型颅咽管瘤显微手术切除中的应用,并比较与其他手术入路的优缺点.方法 回顾性分析22例采用前纵裂入路显微手术切除鞍上脑室内外型大型颅咽管瘤患者,分析手术技巧及术后效果.结果 肿瘤全切20例,次全切除2例,无手术死亡病例.术后发生电解质紊乱15例,尿量增多17例,2-7周后好转,术后1周内视力好转15例.随访6-60个月,肿瘤复发2例,均为12个月内复发.结论 前纵裂入路可直视下处理肿瘤在垂体漏斗部位的粘连,是鞍上脑室内外型颅咽管瘤较好的手术入路.     

Does abnormal interhemispheric inhibition play a role in mirror dystonia?

The presence of mirror dystonia (dystonic movement induced by a specific task performed by the unaffected hand) in the dominant hand of writer's cramp patients when the nondominant hand is moved suggests an abnormal interaction between the 2 hemispheres. In this study we compare the level of interhemispheric inhibition (IHI) in 2 groups of patients with writer's cramp, one with the presence of a mirror dystonia and the other without as well as a control group. The level of bidirectional IHI was measured in wrist muscles with dual‐site transcranial magnetic stimulation with a 10‐millisecond (short IHI) and a 40‐millisecond (long IHI) interstimulus interval during rest and while holding a pen in 9 patients with mirror dystonia 7 without mirror dystonia, and 13 controls. The group of patients without mirror dystonia did not differ from the controls in their IHI level. In contrast, IHI was significantly decreased in the group of patients with mirror dystonia in comparison with the group without mirror dystonia and the controls in both wrist muscles of both the dystonic and unaffected hand whatever the resting or active condition (P = 0.001). The decrease of IHI level in the group of patients with mirror dystonia was negatively correlated with the severity and the duration of the disease: the weaker the level of IHI, the more severe was the disease and the longer its duration. Interhemispheric inhibition disturbances are most likely involved in the occurrence of mirror dystonia. This bilateral deficient inhibition further suggests the involvement of the unaffected hemisphere in the pathophysiology of unilateral dystonia. © 2013 International Parkinson and Movement Disorder Society     

显微镜与内镜下不同纵裂入路的结构显露特点及其解剖结构标志定位

目的探讨显微镜与内镜下不同纵裂入路的结构显露特点及解剖结构标志定位。方法成人尸头10具,分为A组和B组,每组5具,分别采用经前额纵裂入路和经纵裂胼胝体脉络膜裂入路联合室内孔入路,在显微镜和内镜下观察内部结构。结果显微镜与内镜下经前额纵裂入路微创并可充分显露和定位鞍区和第三脑室,有利于切除第三脑室前部和鞍区肿瘤,而经纵裂胼胝体脉络膜裂入路联合室内孔入路微创并可充分显露和定位第三脑室及侧脑室解剖结构,有利于第三脑室、房部、体部及侧脑室额角的手术操作。结论两种纵裂入路均可在显微镜、内镜下充分显露第三脑室等部分结构,组织创伤小,临床上可根据病变特点和手术需求选择合理的入路方式。