The foramen spinosum: a landmark in middle fossa surgery

The foramen spinosum is an easily identifiable landmark in microsurgery of the middle cranial fossa, and knowledge of the variations in its relationship to the surrounding neurovascular structures is important when operating in this area. We studied the anatomical relationship of the foramen spinosum to the foramen ovale, the mandibular branch of the trigeminal nerve, the greater superficial petrosal nerve, and the petrous part of the internal carotid artery in 12 cadaver heads. We also tried to define an external landmark for early identification of the location of the foramen spinosum in ten dry skulls. We found considerable variations in the anatomy around the foramen spinosum. This knowledge may improve the identification and preservation of the neurovascular structures when using approaches to the middle cranial fossa.     

Patent foramen ovale percutaneous closure: indications, techniques and results

A patent foramen ovale is almost physiological (15% of the population) but can be associated with some pathological situations in which its closure can be considered. The only medical indication currently accepted is a right-left shunt without elevation of the right pulmonary pressure, whose most famous pattern is the rare platypnea-orthodeoxie syndrome. PFO may be responsible for diving decompression accidents. Before taking the decision of closing a PFO, each situation must be discussed on a case to case basis. In spite of the possible link between some kinds of migraine and PFO, according to current knowledge, there is no evidence of the efficiency of PFO closure in this situation. The secondary prevention of a cryptogenic ischaemic cerebrovascular attack on a young person with a PFO associated to a membranous septum aneurysm, is the most commonly considered indication, but we lack valid data for this indication. The PFO closing procedure is well codified and its success rate is close to 100%, with rare major complications. Residual permeability within the prosthesis ensuring the closure of the PFO decreases gradually to get under 15% after six months. The clinical result is often dramatic when treating right-left shunts. As far as the secondary prevention of cryptogenic ischaemic cerebro vascular attacks in young people is concerned, there might be some clinical benefit, but we are waiting for the results of ongoing randomized and scheduled studies.     

Foramen magnum meningiomas: experiences in 114 patients at a single institute over 15 years

BackgroundAlthough there has been great development in the anatomical understanding and operative techniques for skull base tumors, controversy still exists regarding the optimal surgical strategies for the FMMs. We report clinical and radiologic features as well as the surgical findings and outcome for patients with FMM treated at our institution over the last 15 years.MethodsWe reviewed 114 consecutive cases of FMM operated between May 1993 and June 2008 in the neurosurgery department at Beijing Tiantan Hospital.ResultsThere were 68 female and 46 male patients (mean age, 52.3 years; range, 28-76 years). Foramen magnum meningiomas were classified as anterior (80 cases), anterolateral (24 cases), and posterolateral (10 cases). Mean duration of symptoms was 11.7 months (ranging from 1.5 to 240 months). Cervico-occipital pain (80.7%) and headache and dizziness (42.1%) were the most common presenting symptoms. The preoperative KPS was 72.5 ± 8.3. Mean maximum diameter of the tumors on MRI was 3.35 cm (range, 1.5-4.7 cm). Posterior midline approach was performed in 10 cases, far-lateral retrocondylar approach in 97 cases, and extended far-lateral approach in 7 cases. Gross total resection was achieved in 86.0% of patients and subtotal resection in 14.0%. Surgical mortality was 1.8%. Follow-up data were available for 93 patients, with a mean follow-up of 90.3 months (range, 1-180 months), of which 59 (63.4%) lived a normal life (KPS, 80-100).ConclusionOur experience suggests that most anterior and anterolateral FMMs can be completely resected by a far-lateral retrocondylar approach without resection of the occipital condyle. Complete resection of the tumor should be attempted at the first operation. Postoperative management of FMM is important for the prognosis.     

Double Foramen Transversarium in Cervical Vertebra an Osteological Study

50 sets of typical dried cervical vertebrae of human were studied for no. of foramen transversarium present on each transverse process of vertebra. So double foramen transversarium were detected unilaterally or bilaterally in 16 vertebrae out of 200 typical (C3-C6) cervical vertebrae. The variation of foramina appears to follow a pattern at various vertebral level.The course of vertebral artery may be distorted under such conditions. The normal factor responsible for such anomalies of foramen transversarium is developmental or related to the variation of course of vertebral artery.     

Intraventricular cavernous hemangioma at the foramen of Monro: Case report and literature review

Cavernous hemangiomas rarely occur in the cerebral ventricles. Those occurring at the foramen of Monro are even less frequent. So far, only eight cases of cavernous hemangioma at the foramen of Monro have been reported in the literature. Here, we present a similar case and correlated the radiographic with the histopathologic findings of the patient. A 51-year-old woman was admitted with obstructive hydrocephalus-related symptoms. The computed tomography (CT) and magnetic resonance imaging (MRI) revealed a partly calcified lesion with slight contrast enhancement located in the area of the right foramen of Monro. The lesion was completely removed by surgical resection with a transfrontal transventricular approach. The resected mass was histologically diagnosed as cavernous hemangioma. The patient's symptoms resolved immediately after operation. Cavernous hemangioma at the foramen of Monro in the present case had common MRI features as previously reported. Although MRI can provide initial diagnosis for such unusually localized tumor, it should be confirmed histopathologically.     

Etomidate accurately localizes the epileptic area in patients with temporal lobe epilepsy

Purpose: A variety of drugs have been used to activate and identify the epileptogenic area in patients during presurgical evaluation. We have evaluated the safety and usefulness of etomidate in identifying the epileptic zone by measuring bioelectrical brain activity and cerebral blood flow (CBF). Methods: We studied 13 men and 9 women under presurgical evaluation for temporal lobe epilepsy. We applied etomidate (0.1 mg/kg) while patients were monitored by video‐electroencephalography (VEEG) with foramen ovale electrodes. In a subset of 15 patients, we also measured CBF with single photon emission computed tomography (SPECT). Results: (1) Etomidate induced seizures in 2 of 22 patients. (2) The main side‐effects observed were myoclonus (14 of 20) and moderate pain (3 of 20). (3) No changes in capillary oxygen saturation, respiration, or heart rate were observed. (4) Irritative activity specifically increased in the temporal mesial and lateral areas. No spikes were observed in other areas, aside from those observed under baseline conditions. (5) Irritative activity induced by etomidate correctly lateralized the ictal onset zone in 19 of 20 patients. In addition, the two etomidate‐induced seizures appeared in the same regions as spontaneous ones. (6) The kinetics of pharmacologically induced activity was higher in the region of the ictal‐onset zone. (7) Etomidate increased the CBF in the basal ganglia and especially in the posterior hippocampus of the temporal mesial region contralateral to the ictal‐onset zone. Discussion: Etomidate activation is a safe, specific, and quick test that can be used to identify the epileptic region in patients evaluated as candidates for temporal lobe epilepsy surgery.     

Temporomandibular joint herniation through the foramen of Huschke with clicking tinnitus

IntroductionThe foramen of Huschke (FH) is an uncommon anatomical variation of the tympanic portion of the temporal bone. It is located on the anteroinferior aspect of the external auditory canal; extremely rarely, the soft tissues around the temporomandibular joint (TMJ) can herniate through it.Case summaryWe report two cases of TMJ herniation through the FH presenting with clicking tinnitus that were treated differently.DiscussionThe treatment of TMJ herniation depends on the presenting symptoms and the patient's willingness to undergo surgical correction. If surgical management is chosen, the bone can be obliterated using tragal cartilage and temporalis fascia.     

Percutaneous radiofrequency thermocoagulation under fluoroscopic image-guidance for idiopathic trigeminal neuralgia

Objective

We retrospectively investigated the long-term results of percutaneous radiofrequency thermocoagulation (RFT) using fluoroscopic image-guidance for treatment of trigeminal neuralgia.

Methods

A total of 38 patients diagnosed and treated with RFT as an idiopathic trigeminal neuralgia were investigated. To minimize the risks related to conventional technique based on cutaneous landmarks, and to eliminate the need to frequent reposition of cannula, we adopted a technique of image-guided fluoroscopic cannulation of the foramen ovale. To minimize sensory complication following thermal lesion, our target response was a generation of a lesion with mild to moderate hypalgesia rather than dense hypalgesia.

Results

The immediate pain-relief was achieved in all patients underwent RFT. With mean duration of follow-up of 38.2 months (range,12-72), 11 (28.9%) experienced recurrence of pain. The mean timing of recurrence was 26.1 months (range,12-46). A 42.7% recurrence rate was estimated by Kaplan-Meier analysis for the 38 patients at 46 months; 20.2% within 2 years, 29.1% within 3 years. In the long-term, 27 patients (71%) and 6 patients (15.8%) showed Barrow Neurological Institute (BNI) score I and BNI score II responses. 3 (7.9%) patients was assessed as BNI score III, 2 patients (5.3%) showed BNI score IV response. As a complication, troublesome dysesthesia occurred in 3 of 38 patients (7.9%), however, there was no permanent cranial nerve palsy or morbidity.

Conclusion

These results indicates that RFT under fluoroscopic image-guided cannulation of foramen ovale is a safe, effective, and reliable means of treating trigeminal neuralgia.     

经颅多普勒发泡试验结合反常性栓塞风险量表在卵圆孔未闭合并不明原因卒中筛查中的应用价值

目的 探讨经颅多普勒发泡试验(c-TCD)结合反常性栓塞风险量表(RoPE)评分在卵圆孔未闭合并不明原因卒中筛选的价值.方法 回顾性分析2013年9月至2019年10月西安市第五医院收治的脑卒中病人217例为研究对象,根据卵圆孔未闭诊断"金标准"食管超声心动图(TEE)分为卵圆孔未闭组(62例)和非卵圆孔未闭组(155例),收集两组一般资料,分析两组c-TCD[c-TCD阳性率、右向左分流(RLS)分流量]、RoPE评分情况;Spearman相关分析法评估卵圆孔未闭合并不明原因卒中病人RoPE评分与c-TCD阳性率、RLS分流量的相关性.结果 两组性别、年龄、高血压史、糖尿病史、高血脂史、吸烟史、偏头痛史、发病至核磁共振检查时间均差异无统计学意义(P>0.05).非卵圆孔未闭组c-TCD微泡数量阳性例数(4例)与卵圆孔未闭组c-TCD微泡数量阳性例数(48例)比较差异有统计学意义(P<0.05).非卵圆孔未闭组RoPE评分(6、7、8、9、10分)分别有49、48、34、18、6例与卵圆孔未闭组RoPE评分(6、7、8、9、10分)分别有8、7、8、15、24例比较差异有统计学意义(P<0.05).Spearman相关分析显示,卵圆孔未闭合并不明原因卒中病人RoPE评分与c-TCD阳性率、RLS分流量呈正相关(rs=0.896、0.876,P<0.001).结论 c-TCD结合RoPE量表可用于卵圆孔未闭合并不明原因卒中的筛选,具有一定价值.     

Changes in the foramen magnum axis during human foetal life

The present findings showed that in early embryonic life the foramen magnum plane has a direction, more like that found in most animals in the sagittal plane due to the cervical flexure found at this early developmental period. Gradually during the foetal period the inclination of the foramen magnum plane changes to a more perpendicular relationship with the trunk preparing for a future erect posture. It was thought that the most important factor in this change of inclination is the rapid growth of the cerebral cortex. The study was carried out in order to see if possible changes in axial inclination of the foramen magnum axis in the sagittal plane can partly explain the changes in the cephalic flexure during foetal life. The material consisted of 38 selected human foetuses and 4 skulls of newborn babies.