Midline suboccipital burr hole for posterior fossa craniotomy

Background

Posterior fossa craniotomy is generally done starting with two lateral burr holes. Single midline burr hole is often avoided for the fear of injury to the venous sinuses. In this paper, we retrospectively evaluated the risk of dural tear or venous sinus injury with the latter approach.

Methods

Patients who had a posterior fossa craniotomy at the Children’s Hospital of Michigan between 2003 and 2009 were analyzed. Seventy-one patients had been operated for a posterior fossa lesion, and 154 had a Chiari I decompression. Suboccipital craniotomy was performed utilizing a starting midline suboccipital burr hole. The craniotomy was completed using Midas Rex with B1 foot plate starting laterally from the burr hole and then over to the foramen magnum including the foramen magnum lip. In patients who had a tumor resection, the bone flap was replaced and secured with plates on both sides.

Results

One patient had a dural tear along the inferior aspect of the craniotomy not extending into the foramen magnum. There was no instance of venous sinus injury or undue bleeding from the burr hole. None of the patients had an infection requiring removal of the bone flap.

Conclusion

This paper confirms the safety of utilizing midline burr hole for starting a posterior fossa craniotomy.     

Simulation to Locate Burr Hole Sites in a Patient for Deep Brain Stimulation Surgery and Clipping of Intracranial Aneurysm

Background and Objective: Deep brain stimulation (DBS) candidates with neurologic diseases such as unruptured aneurysm present additional challenges to neurosurgeons when craniotomy must precede DBS surgery. Such craniotomy may potentially overlap with intended burr hole sites for the later insertion of DBS electrodes, and the skin incision for craniotomy may lie very close to or intersect with that for the burr holes. We report here a case of forehead craniotomy prior to DBS surgery in which we employed a neuronavigation system to simulate locations for the craniotomy and burr holes. Method: A 62‐year‐old male patient with Parkinson's disease was a candidate for DBS. He also had an aneurysm and was planned first to undergo frontal craniotomy for clipping before the DBS surgery. The locations of the craniotomy, burr holes, and skin incisions were therefore simulated using a neuronavigation system during craniotomy. Results: Two weeks after the craniotomy, the patient underwent DBS surgery. Planning software confirmed the absence of cortical veins beneath the entry points of tentative burr holes and aided trajectory planning. The DBS surgery was performed without the interference of the burr holes and head pins and the craniotomy. Conclusion: Simulation of the locations of craniotomy and burr holes using a neuronavigation system proved valuable in the present case of frontal craniotomy before DBS surgery.     

颞下小骨窗人路显微手术临床应用

目的改良常规颢下人路,以减少手术创伤达到微创的目的。方法采用耳前1cm颧弓向上向后弧形切口,绕行耳廓上方约1cm到达乳突,铣开4cm×2cm大小骨窗,平中颅底,经颞下行中颅底部位病灶的手术治疗15例。结果9例三叉神经鞘瘤全切除8例,次全切1例。4例岩尖区天幕下脑膜瘤和2例颞底胶质瘤均全切除。结论颞下小骨窗人路可以达到常规颞下入路的效果,可以满足中颅窝后部、颞叶底面及天幕区的肿瘤切除术的要求,是一种行之有效的微创手术人路。     

Intraorbital Encephalocele Presenting with Exophthalmos and Orbital Dystopia : CT and MRI Findings

A 15-year-old female patient with progressive pulsatile exophthalmos caused by intraorbital encephalocele was evaluated with computed tomography (CT) and magnetic resonance imaging (MRI) in our clinic. She had no history of trauma or reconstructive surgery. When she was a little girl, she had undergone surgery for congenital glaucoma on the right eye. On the three-dimensional image of CT, a hypoplasic bone defect was observed in the greater wing of the right sphenoid bone. MRI and CT scan showed herniation through this defect of the arachnoid membrane and protruded cerebral tissue into the right orbita. Intraorbital encephalocele is an important entity that can cause pulsatile exophthalmos and blindness.     

经枕下乙状窦后-内听道上结节入路切除岩斜区脑膜瘤

目的探讨采用枕下乙状窦后-内听道上结节入路切除岩斜区脑膜瘤的安全性、有效性,以及优缺点。方法回顾性分析自2002年1月至2004年12月采用枕下乙状窦后-内听道上结节入路切除的岩斜区脑膜瘤11例。所有肿瘤主体均位于后颅窝,侵袭海绵窦和/或Meckel's腔,其中6例伴有脑干受压移位,3例有岩尖骨性改变,5例肿瘤部分或全部包绕椎基底动脉及其主要分支。结果肿瘤全切除8例,次全切除3例。术前有听力者9例,其中1例因肿瘤巨大,术后听力丧失。出院后随访,7例、3例和1例面神经功能分别恢复至1级、2级和3级。所有患者术后恢复满意,无死亡和严重并发症发生。结论枕下乙状窦后-内听道上结节入路是一种安全有用的乙状窦后改良入路,适合于主体在后颅窝,并向中颅窝、Meckel's腔扩展的岩斜区大型肿瘤的手术切除。     

Tension pneumocephalus after intracranial surgery in the supine position

Tension pneumocephalus is a rare and severe complication appearing after posterior fossa procedures in the sitting position. This complication may endanger the patient's life and require immediate treatment. However, tension pneumocephalus after neurosurgical procedure in the supine position have been scarcely reported. We report such a complication occurring in a 14-year-old girl submitted to a frontotemporal craniotomy for removal of an astrocytome performed with the patient supine. We discuss ethiopathogenesis and management of this complication.     

Medulloblastoma in childhood: comparative results of partial and total resection.

51 medulloblastomas under 12 years of age were treated from 1966 through 1977. 50 patients underwent craniotomy and 39 of them completed postoperative radiation therapy. Surgical mortality rate of primary posterior fossa craniotomy was 8%. One year survival rate was 71.4%, 3 years 45.6% and 5 years 34.5%. Extent of surgical resection was found to affect the survival, and a group of radical or visibly total resection showed higher postoperative survival. Female patients enjoyed longer survival. The patients under 12 months of age showed poor prognosis. Reexploration of the posterior fossa failed to prolong the survival by more than 3 months.     

Cervical spinal deformity following craniotomy and upper cervical laminectomy for posterior fossa tumors in children

Spinal deformity is not usually regarded as a potential complication of posterior fossa tumor resection. After cervical subluxation had been recognized in 2 children following removal of posterior fossa tumors, a review was carried out to determine the incidence of this complication. Of the 72 children who had undergone resection of a posterior fossa tumor, 4 patients, including the original 2, developed a cervical spinal deformity. Factors that predisposed to this complication included laminectomy of C2 or lower, local wound complications and possibly post-operative neck weakness. It is important to be aware that cervical subluxation can occur after resection of posterior fossa tumors, when laminectomy extending below C1 has been performed. Patients at risk should be followed closely.     

侧脑室内脑膜瘤的诊断与治疗

目的探讨侧脑室内脑膜瘤的诊断、鉴别诊断和手术治疗方法,以提高对其的诊治水平。方法回顾性分析我院自1983年4月至2005年9月手术治疗的36例侧脑室内脑膜瘤患者临床资料,并复习相关文献。结果本组患者均行手术,肿瘤全切除35例,次全切除1例。1例患者术后10d死于高血糖昏迷诱发的多器官功能不全综合征。术后恢复良好34例,中残1例,无手术死亡病例。16例患者随访3个月至9年,有2例患者肿瘤复发,其余患者头痛症状消失,无恶心呕吐,视力好转,失语及偏瘫患者症状有不同程度好转。结论侧脑室内脑膜瘤术前诊断依赖CT及MRI检查,选择适合的手术入路,采用显微技术可以全切除肿瘤,保护神经功能完整。     

Dedifferentiated chordoid meningioma with rhabdomyosarcomatous differentiation on the middle cranial fossa

A 46‐year‐old woman presented with headache and right hemiparesis. MRI demonstrated a mass in the left middle fossa. Total resection was performed. A histological examination of the tumor specimen showed several characteristic morphological features. A chordoid meningioma showing an epithelial‐like palisade arrangement was observed. An anaplastic short spindle cell tumor exhibiting a fascicular pattern was considered to be a rhabdomyosarcoma. After conventional radiotherapy, the tumor was well controlled without any neurological deficit for 20 months. When subsequent recurrences were observed, the patient was treated by surgery, stereotactic radiosurgery and chemotherapy. Thirty‐two months after the initial treatment, the patient died due to intracranial dissemination and an autopsy was performed. The histological examination of the recurrent and autopsy specimens showed a prominent sarcoma component. This case appears to be the first reported intracranial tumor diagnosed as a dedifferentiated chordoid meningioma with rhabdomyosarcomatous differentiation.     

Cerebrospinal Fluid Rhinorrhea and Seizure Caused by Temporo-Sphenoidal Encephalocele

This case report describes the symptoms and clinical course of a 35-year-old female patient who was diagnosed with a temporo-sphenoidal encephalocele. It is characterized by herniation of cerebral tissue of the temporal lobe through a defect of the skull base localized in the middle fossa. At the time of first presentation the patient complained about recurrent nasal discharge of clear fluid which had begun some weeks earlier. She also reported that three months earlier she had for the first time suffered from a generalized seizure. In a first therapeutic attempt an endoscopic endonasal approach to the sphenoid sinus was performed. An attempt to randomly seal the suspicious area failed. After frontotemporal craniotomy, it was possible to localize the encephalocele and the underlying bone defect. The herniated brain tissue was resected and the dural defect was closed with fascia of the temporalis muscle. In summary, the combination of recurrent rhinorrhea and a first-time seizure should alert specialists of otolaryngology, neurology and neurosurgery of a temporo-sphenoidal encephalocele as a possible cause. Treatment is likely to require a neurosurgical approach.     

The retrosigmoid approach to petroclival meningioma surgery

Petroclival meningiomas are technically challenging lesions. The authors retrospectively analyzed their experience between 2000 and 2010 in 82 patients with petroclival meningioma to evaluate changes in management strategy. A total of 42 patients (51%) were treated via the retrosigmoid approach. The patients received postoperative neurological and neuroradiological follow-up. The maximum diameter of the tumors ranged from 1.5 cm to 6.5 cm (mean, 3.8 cm). Gross total resection (Simpson Grade II) was achieved in 27 patients (64%), subtotal resection (Simpson Grade III) in 11 (26%), and partial removal (Simpson Grade IV) in four (9.5%). Ten patients (24%) had new neurological deficits or worsening of pre-existing deficits. One patient (2%) died because of brainstem dysfunction after surgery. The retrosigmoid approach is suitable for treatment of selected petroclival meningioma if the main part of the tumor is located in the posterior fossa in the cerebellopontine angle and the low clivus, and only a minor part of the tumor extends to the posterior wall of the cavernous sinus. This approach provides a low degree of surgical difficulty and a low complication rate.     

预缝式关颅联合颅内压监测下控制性减压在PADBS手术中的作用探讨

目的探讨预缝式关颅联合颅内压监测下控制性减压在外伤性急性弥漫性脑肿胀(PADBS)手术中的应用价值。方法选择湖州市第一人民医院神经外科自2015年2月至2019年12月收治的157例PADBS患者为研究对象,并将其中2017年6月前收治的采用颅内压监测下控制性减压手术治疗的68例患者纳入对照组,2017年6月后收治的采用预缝式关颅联合颅内压监测下控制性减压手术治疗的89例患者纳入试验组,回顾性对比分析2组患者间术中开颅时间、脑组织暴露时间、关颅时间、急性脑膨出发生率及伤后6个月格拉斯哥预后量表(GOS)评分的差异。结果试验组患者的术中开颅时间[(19.2±1.6)min]明显长于对照组[(15.4±1.4)min],脑组织暴露时间[(18.5±2.4)min]明显短于对照组[(26.3±2.2)min],关颅时间[(11.2±1.5)min]明显短于对照组[(18.3±2.1)min],急性脑膨出发生率(22.5%)明显低于对照组(38.2%),预后良好率(70.8%)明显高于对照组(50.0%),死亡率(6.7%)明显低于对照组(17.6%),差异均有统计学意义(P<0.05)。结论预缝式关颅联合颅内压监测下控制性减压能够缩短关颅时间及脑组织暴露时间,降低急性脑膨出发生率,更有效地改善PADBS患者的预后。     

Intraoperative supratentorial epidural haematoma during removal of a huge posterior fossa dermoid cyst

Epidural haematomas may occur following cranial operations, and most of them are located near the craniotomy or burr-hole areas. There are very few cases of supratentorial epidural haematoma following the resection of giant tumours located in the posterior fossa. In this case report, we present a patient who developed an acute left temporoparietal epidural haematoma in the perioperative period during the excision of a huge dermoid cyst in the posterior fossa.     

小骨窗经前纵裂入路切除鞍上脑膜瘤29例

目的探讨鞍上脑膜瘤经前纵裂入路切除的价值及效果。方法 29例经MRI检查及术后病理检查确诊为鞍上脑膜瘤患者,瘤体最大直径3～6 cm,采用小骨窗(约4 cm×5 cm)经前纵裂入路显微手术切除。结果肿瘤全切除25例(86%)(SimpsonⅠ、Ⅱ),次全切除4例。视力视野改善者19例。术后尿崩症2例,电解质紊乱1例,无手术死亡。结论鞍区脑膜瘤向前方、上方、鞍内生长者,采用小骨窗经前纵裂入路能较好显露瘤体,脑组织牵拉轻,并发症发生率低,显著提高肿瘤的全切除率。     

A healthy man with intractable hiccups

We present a patient with intractable hiccups. Medical treatment decreased the frequency of the hiccups to only 5–10 per minute. After exclusion of gastrointestinal reasons for the hiccups, cranial MRI revealed a small lesion in the right rhomboid fossa, close to the vagal trigone. Microsurgical resection of the lesion was performed via a suboccipital median craniotomy. The histopathological diagnosis was a cavernoma. Promptly after surgery the patient was free of symptoms. Intractable hiccups can be associated with intracranial pathologies, including lesions in the brain stem, which we highlight with the presentation of this patient.     

术前栓塞联合手术切除颅后窝实质性血管母细胞瘤的疗效分析

目的 探讨术前栓塞联合手术切除颅后窝实质性血管母细胞瘤的疗效。方法 回顾性分析2011年1月至2021年6月手术治疗的56例颅后窝实质性血管母细胞瘤的临床资料。结果 56例中,21例（观察组）先行血管内栓塞治疗,再行开颅肿瘤切除术;35例（对照组）直接行开颅肿瘤切除术。与对照组相比,观察组肿瘤切除时间明显缩短（P<0.05）,术中出血量明显减少（P<0.05）,肿瘤全切除率明显提高（P<0.05）,术后3个月KPS评分明显改善（P<0.05）。结论 颅后窝实质性血管母细胞瘤血供丰富,先行血管内栓塞处理肿瘤供血动脉,可有效减少术中出血,提高肿瘤全切率,改善病人预后。     

Chiari畸形并脊髓空洞症的MRI分型及其治疗

对Ｃｈｉａｒｉ畸形并脊髓空洞症治疗方法及其效果的探讨。方法对１０３例Ｃｈｉａｒｉ畸形病例根据其ＭＲＩ征像分为Ａ、Ｂ、Ｃ三种类型。结果依据其类型采用不同的手术方式,并获得了较为满意的治疗效果。结论手术使延颈髓充分减压,可有效缓解临床症状,并对脊髓空洞症有明显的治疗作用。     

A rare tentorial mesenchymal chondrosarcoma in posterior cranial fossa: Case report

Intracranial extraskeletal mesenchymal chondrosarcoma is a very rare malignant tumor with predilection site of frontoparietal falx cerebri. Only few cases of mesenchymal chondrosarcoma in posterior cranial fossa are reported. Here, we report a 23-year-old young man with a dura-attached mass in left posterior cranial fossa misdiagnosed as a tentorial meningioma preoperatively. According to the following operation, the lesion was confirmed as mesenchymal chondrosarcoma surgically and pathologically. On MRI, the tumor was characterized by lobulated soft-tissue mass with dura-attached base, patchy calcifications and heterogeneous signal intensities. On contrast-enhanced MRI, it was well-defined, with marked enhancement. We consider that these imaging features above might remind us to consider the diagnosis of mesenchymal chondrosarcoma in posterior cranial fossa. The postoperative treatment of radiotherapy is still controversial. As for our case, according to the 24 months follow-up after postoperative γ-knife, our patient shows an optimistic prognosis so far.     

Hypoglossal schwannoma presenting as hemi-atrophy of the tongue

Schwannoma of the hypoglossal nerve is extremely rare. We report the clinical manifestations of a patient with Schwannoma of the hypoglossal nerve with hemi-atrophy of the tongue and numbness in the lip. Magnetic resonance image study of the brain showed a lobulated mass at the right posterior fossa with an extension to the right upper neck. Surgical intervention was performed with right occipital craniotomy and a partial resection of C1 and occipital condyle. Pathological studies confirmed a Schwannoma with hemorrhages and necrosis.