Microsurgical Resection of Craniocervical Dermoid Cyst by Far Lateral Approach: Case Report and Literature Review

Introduction Intracranial dermoid tumors represent a rare clinical entity that accounts for 0.04 to 0.6% of all intracranial tumors. Their location in the posterior fossa is uncommon. Objectives To report the case of a young woman with a posterior fossa dermoid cyst treated by right far lateral approach. Case Report A 17-year-old woman presenting with swallowing difficulties for 6 weeks was referred for a neurological investigation. Amagnetic resonance imaging (MRI) scan showed a hyperintense T1-weighted large expansive lesion occupying the posterior fossa and compressing the anterior face of the brain stem and cerebellum. The patient underwent surgical treatment by right far lateral approach with decompression of vascular and neural structures. The patient presented an uneventful recovery, and was discharged home on the fourth postoperative day without any additional neurological deficits. The anatomopathological analysis confirmed the diagnosis of dermoid cyst. Conclusion The far lateral approach is a safe and feasible route to appropriately treat large posterior fossa dermoid cysts. Decompression of vascular and neural structures is essential to achieve good symptom control.

Foramen Magnum Meningioma Presenting with Cough Syncope (Case Report and Review of the Literature)

Foramen magnum meningiomas cause different symptoms based on the size and the location of the tumor. They often present with involvement of the long tracts and of the lower cranial nerves.Ataxia and occipitocervical headache are other common symptoms. In the present study, we report a case of foramen magnum meningioma presenting with cough syncope. A mass lesion located anterolateral to the foramenmagnumwas detected in a 38-year-oldmanduring amagnetic resonance imaging (MRI) exam; the lesion extended from the inferior clivus to the level of the C2 vertebra. The neural axis has pushed towards posterior and contralateral side by the mass. We think that syncope occurred due to the encasement of the vertebral arteries by the tumor in addition to the compression of the neural axis. The posterolateral approach without condylar resection provides a safe surgical plane for total excision of these tumors. In our case, the tumor was totally removed and the syncope episodes were resolved.

Treatment of vertebrobasilar aneurysms using suboccipital muscle stratification via far lateral approach / 中国脑血管病杂志

Objective To discuss the technical essentials of microsurgery using suboccipital muscle stratification for the treatment of complex vertebrobasilar aneurysms via far lateral approach.Methods The clinical data of 8 patients with vertebrobasilar aneurysm underwent suboccipital muscle stratification via far lateral approach at the Department of Neurosurgery,Xuanwu Hospital,Capital Medical University were analyzed retrospectively,including 5 patients with subarachnoid hemorrhage (Hunt-Hess grade Ⅱ 3 cases;grade Ⅲ 1 case;grade Ⅳ 1 case),and 3 with symptomatic dissecting aneurysm.Six patients underwent occipital artery-posterior inferior cerebellar artery and anterior inferior cerebellar artery bypass grafting,and aneurysm trapping,and the aneurysms of the other 2 cases were clipped directly in the operation.The modified Rankin scale (mRS) was used to evaluate the clinical efficacy.Results Postoperative digital subtraction angiography (DSA) revealed that all the bridge vessels were patent.The obtained length of occipital artery in the actual measurement of the operation was 12.5±1.1 cm.The distance between the anastomosis site and the skin incision in 6 cases was 50±6 mm.They were followed up for 4-21 months after procedure.The mRs score in 7 cases was 0-1.Two patients had new-onset hoarseness and recovered completely within 3 months after procedure.Another patient had postoperative cerebellar hemisphere dominant regional cerebral infarction and the mRs score was 4.None of them had poor wound healing,infection and cerebrospinal fluid leakage after procedure.Conclusion Suboccipital muscle stratification via far lateral approach can effectively obtain a longer occipital artery,reduce the occupation effect of muscle and depth of field.It is beneficial to expose lesions and operation of deep anastomosis.It is a more safe and practical technique in neurosurgery for the treatment of vertebrobasilar artery aneurysms.

Clinical anatomy study of the far lateral suboccipital approach / 局解手术学杂志

Objective To study the microsurgical anatomy marks and parameters for thefar lateral suboccipital approach and to protect the vital structure in operations. Methods Through the far lateral suboccipital approach, 10 adult cadveric heads were anatomized. Under the microscopy, the involving muscles, bony structures, vessels and nerves were observed and measured anatomically. Results The distance from asteria to asteria was (21. 68 ± 1. 88) mm on the left and (22. 34 ± 2. 62) mm on the right. The distance from anterior asteria to mas-toidale was (38. 56 ± 3. 48) mm on the left and (39. 14 ± 2. 24) mm on the right. The distance from asteria to root of zygoma was (55. 72 ± 3. 64) mm on the left and (56. 16 ± 2. 72) mm on the right. Conclusion The suboccipital triangle and C2 nerve were the significant marks which can identify the vertebral artery. The bone anatomic landmarks in the far lateral suboccipital approach included anterior asteria, aste-ria, mastoidale and root of zygoma. These marks contributed the successful implementation of the far lateral suboccipital approach surgery.

The far-lateral craniotomy: tips and tricks / A craniotomia extremo-lateral: dicas e truques

This article intends to describe in a didactical and practical manner the suboccipital far-lateral craniotomy. This is then basically a descriptive text, divided according to the main stages involved in this procedure, and that describes with details how the authors currently perform this craniotomy.

O presente artigo visa descrever de forma didática e prática a realização da craniotomia suboccipital extremo-lateral. Trata-se, portanto, de um texto fundamentalmente descritivo, dividido conforme as principais etapas da realização dessa craniotomia, e que descreve com detalhes a técnica com que o presente grupo de autores evolutivamente veio a realizá-la.

Microsurgical anatomy and clinical study of the far lateral suboccipital approach / 医学研究生学报

Objective:To investigate the microsurgical anatomy of the far lateral suboccipital approach and to evaluate its application to surgical approach. Methods:Fourteen cadaveric heads(28 sides) were dissected through far lateral suboccipital approach to obtain the anatomical data of this approach.A retrospective analysis of microsurgical treatment in 12 cases of tumors situated at lower clivus and foramen magnum was performed. Results:Transverse process of C_1 and inferior occipital trangle were important anatomical marks in the far lateral occipital approach.Drilling the condyle and jugular tubercle was benefit to expand the surgical space.Total removal of the turmors was achieved in 9 patients,subtotal removal in 3 patients,and without any surgical morbidity. Conclusion:Study on the microsurgical anatomy of the far lateral suboccipital approach was helpful in resecting tumors situated at lower clivus and foramen magnum.

Microsurgical anatomy on the design of the far-lateral supracondylar keyhole approach / 中华显微外科杂志

Objective To explore the posibility of removing the jugular tubercle precisely and design a new far-lateral supraeondylar keyhole approach based on keyhole idea.Methods Eight cadaveric heads fixed by 10% formalin and perfused intracranial vessels with colored silicone were used in this study.Before the operation,navigation data of these cadaveric heads were established and circumscriptions of jugular tuber- cle were outlined in the navigation system in order to aid drilling it in operation.A 7cm longitudinal“S”shaped skin incision as we reported was performed.After inverting suboccipital muscles and exposing the far lateral of the occipital bone,occipital condyle,jugular tubercle,hemilamina of C_1,vertebral artery and pos- terolateral portion of foramen magnum,a 3cm retro-condylar bone window was made.Under the microscope, anatomic structures were observed and important structures were measured after jugular tubercle removal assis- ted by neuro-navigation.Results The 7cm longitudinal“S”shaped skin incision with its superior border 2cm behind the middle point of mastoid and inferior margin at the level of C_2 can fully meet the needs of the far-lateral supracondylar keyhole approach;jugular tubercle can be drilled satisfactorily with the help of neuro- navigation;inferior segment of basilar artery[long(15.65?1.34)mm]and anterior inferior cerebellar artery [long(20.36?4.18)mm] can be exposed.Conchlsion Owing to the area of middle clivus is increasingly exposed after removal of jugular tubercle,it is feasible to perform the far-lateral supracondylar keyhole ap- proach on the operations of vertebral-basilar artery aneurysm,anterior inferior cerebellar artery aneurysm and tumor located inferior and middle clivi or jugular foramen.