Sinus pericranii in children: report of 16 patients and preoperative evaluation of surgical risk

J Neurosurg Pediatrics 4:050360–500420, 2009.(DOI: 10.3171/2009.7.PEDS0994)

Sinus pericranii (SP) is a rare venous varix in an extracranial location connected to the intracranial venous system. The aim of this retrospective study was to report on 16 pediatric cases of SP with consideration of the preoperative evaluation of surgical risk.

Methods. The study population consisted of 10 patients who had undergone surgery for SP and 6 patients with concomitant craniosynostosis and SP. The mean age of the patients at presentation was 3.7 years. To identify characteristics of SP with high operative risk, 8 cases in this report and 11 previously reported cases of SP with sufficient information were categorized on the basis of the number and size of SP, the number and size of transcranial channels, the venous drainage type, and the amount of blood loss. Hemorrhage amounts were classified into 3 grades based on the description of intraoperative blood loss.

Results. Sinus pericranii not associated with craniosynostosis were resected without any postoperative morbidity. Sinus pericranii associated with craniosynostosis were preserved. After craniofacial reconstruction, 2 cases of SP with craniosynostosis regressed, completely in one patient and partially in another. These 2 patients with SP were confirmed to have compromised intracranial sinus before craniofacial reconstruction. Among a total of 19 patients, multiplicity or size (> 6 cm) of SP (p = 0.036) and multiplicity (> 3) or size (> 3 mm) of transcranial channels (p = 0.004) was associated with more severe hemorrhage grade. Sinus pericranii with peripheral venous drainage (drainer type) was not associated with hemorrhage grade after classification into 3 grades (p = 0.192). However, all 3 cases of SP with massive Grade 3 hemorrhage were the drainer type. Hemorrhage grade was correlated with the number of risk factors for SP (r = 0.793, p < 0.001).

Conclusions. Three risk factors of SP and the presence of compromised intracranial sinus are markers for high-risk SP. “Squeezed-out sinus syndrome” is suggested as a concept for SP associated with compromised intracranial sinus, mainly caused by craniosynostosis. Sinus pericranii in squeezed-out sinus syndrome probably serves as a crucial alternative to venous drainage of the brain with intracranial venous compromise. Conservative treatment for such patients with SP is recommended.


Deep brain stimulation of the subcallosal cingulate gyrus for depression

J Neurosurg 111:1209–1215, 2009.(DOI: 10.3171/2008.10.JNS08763)

Object. Deep brain stimulation (DBS) of the subcallosal cingulate gyrus (SCG), including Brodmann area 25, is currently being investigated for the treatment of major depressive disorder (MDD). As a potential emerging therapy, optimal target selection within the SCG has still to be determined. The authors compared the location of the electrode contacts in responders and nonresponders to DBS of the SCG and correlated the results with clinical outcome to help in identifying the optimal target within the region. Based on the location of the active contacts used for long-term stimulation in responders, the authors suggest a standardized method of targeting the SCG in patients with MDD.

Methods. Postoperative MR imaging studies of 20 patients with MDD treated with DBS of the SCG were ana- lyzed. The authors assessed the location of the active contacts relative to the midcommissural point and in relation to anatomical landmarks within the medial aspect of the frontal lobe. For this, a grid with 2 main lines was designed, with 1 line in the anterior-posterior and 1 line in the dorsal-ventral axis. Each of these lines was divided into 100 units, and data were converted into percentages. The anterior-posterior line extended from the anterior commissure (AC) to the projection of the anterior aspect of the corpus callosum (CCa). The dorsal-ventral line extended from the inferior portion of the CC (CCi) to the most ventral aspect of the frontal lobe (abbreviated “Fr” for the formula).

Results. Because the surgical technique did not vary across patients, differences in stereotactic coordinates between responders and nonresponders did not exceed 1.5 mm in any axis (x, y, or z). In patients who responded to the procedure, contacts used for long-term stimulation were in close approximation within the SCG. In the anterior- posterior line, these contacts were located within a 73.2 ± 7.7 percentile distance from the AC (with the AC center being 0% and the line crossing the CCa being 100%). In the dorsal-ventral line, active contacts in responders were located within a 26.2 ± 13.8 percentile distance from the CCi (with the CCi edge being 0% and the Fr inferior limit being 100%). In the medial-lateral plane, most electrode tips were in the transition between the gray and white matter of SCG.

Conclusions. Active contacts in patients who responded to DBS were relatively clustered within the SCG. Be- cause of the anatomical variability in the size and shape of the SCG, the authors developed a method to standardize the targeting of this region.


External ventricular drain insertion accuracy: is there a need for change in practice?

Neurosurgery 65:1197–1201, 2009.DOI: 10.1227/01.NEU.0000356973.39913.0B

OBJECTIVE: Free-hand insertion of an external ventricular drain (EVD) is a common emergency neurosurgical procedure, mostly performed for critically ill patients. Although EVD complications have been studied thoroughly, the accuracy of EVD positioning has been audited only occasionally.

METHODS: Post-EVD insertion computed tomographic scans performed in our unit over a 2-year period were analyzed for EVD tip location and intracranial catheter length.

RESULTS: A total of 183 post-EVD insertion scans were reviewed. Of those, 73 EVD tips (39.9%) were in the ipsilateral frontal horn of the lateral ventricle (the desired tar- get); of those, 18 (25%) required EVD revision/reinsertion. Of the others, 35 (19.1%) were in the third ventricle, 33 (18%) in the body of the lateral ventricle, 19 (10.4%) in the sub- arachnoid space, 5 (2.7%) in the contralateral frontal horn, and 18 (9.8%) within the brain parenchyma. When the EVD tip was outside the desired target, 44 of the patients (40%) required EVD revision/reinsertion procedure (P = 0.0383).

CONCLUSION: Free-hand insertion of an EVD is an inaccurate procedure, and further studies are required to assess the accuracy and feasibility of the routine use of neuro- navigation, ultrasonography, or other guidance techniques and the possible implication of the decreasing revision rate, complications, and length of hospital stay.

Wound healing after craniotomy: a randomized trial comparing scalp clips to artery forceps for scalp hemostasis

J Neurosurg 111:1175–1178, 2009.(DOI: 10.3171/2009.5.JNS081481)

Object. In this prospective randomized clinical trial, investigators looked at wound healing after craniotomy. The hypothesis was that the self-closing plastic scalp clips used for hemostasis on the skin edge might lead to local  ized microscopic tissue damage and subsequent delayed wound healing.

Methods. The trial consisted of 2 arms in which different methods were used to secure scalp hemostasis: 1) the routinely­used­plastic­clips (Scalpfix,­Aesculap); and 2)­the older method of artery forceps placed on the galea. Participants were restricted to those > 16 years of age undergoing craniotomies expected to last > 2 hours. Repeat operations were not included. One hundred fifty patients were enrolled.­They were visited at 3 and 6 weeks postoperativel by an observer blinded to the method used, and the wounds were assessed for macroscopic epithelial closure, signs of­infection, and hair regrowth by using a predefined assessment scale.

Results.­The results showed no significant difference in wound healing between the 2 groups at either 3 weeks (OR 0.55, 95% CI 0.27–1.11; p = 0.09) or 6 weeks (OR 0.79, 95% CI 0.39–1.58; p = 0.50). The length of operation was found to be a significant factor affecting wound healing at 6 weeks (OR/hour 0.68,­95%­CI 0.51–0.92; p­=0.01)

Conclusions.­The use of Aesculap Scalpfix self-retaining plastic scalp clips on the skin edge during craniotomy surgery does not appear to affect wound healing significantly to the postoperative 6 week mark.


Occipital inter-hemispheric approach for lateral ventricular trigone meningioma

Acta Neurochir (2009) 151:1717–1721. DOI 10.1007/s00701-009-0310-9

Objective The optimal surgical approach for a trigone meningioma is still controversial. Here, we report two patients with trigone meningioma treated successfully via an occipital inter-hemispheric and trans-cortical approach in the lateral semi-prone position.

Clinical presentation A 53-year-old woman was admitted to a local hospital with sudden transient dizziness and vomiting. The CT brain scan demonstrated a right intraventricular tumour. She was therefore transferred to our hospital for surgical treatment. The other patient was a 67- year-old woman who was admitted to a local hospital after a traffic accident and a CT brain scan revealed an incidental right intra-ventricular tumour. After referral to our hospital, periodic MRI examinations revealed gradual tumour enlargement within a one-year period. Neither of the patients had any neurological deficits, including in the visual fields.

Intervention The head of each patient was positioned so that the tumour-containing right ventricle was oriented downwards and laterally. An occipital inter-hemispheric approach was performed and using a navigation system, the tumour was identified about 1 cm in depth from the cortical surface. After the medial part of the tumour was debulked, the posterior and then the anterior choroidal blood supplies to the tumour were identified. Occlusion of these vessels achieved tumour haemostasis. The tumours were totally removed via a 1.5-cm cortical incision. Brain retraction was minimal because the right hemisphere was pulled down by gravity. Therefore, the para-splenial cisterns were easily accessed, resulting in early release of cerebrospinal fluid.

Post-operative MRI showed complete removal of the tumour and the patients had no neurological deficits. Antiepileptic medication was withdrawn one week after the operation. Conclusions The occipital inter-hemispheric fissure lacks important bridging veins. The approach used and patient positioning minimized damage to the lateral aspect of the optic radiation and the corpus callosum. Except in patients with very large trigone meningiomas, this approach is useful for decreasing the risk of post-operative hemianopsia or epilepsy, and possibly speech disturbance, even in patients with a tumour in the dominant hemisphere.


Endoscopic third ventriculostomy for obstructive hydrocephalus in children younger than 6 months of age

Childs Nerv Syst. DOI 10.1007/s00381-009-1019-z

The outcome of endoscopic third ventriculostomy (ETV) is worse in children younger than 2 years old and especially in infants, and controversies still exist whether ETV might be superior to shunt placement in this age group. We retrospectively analyzed the data of 23 patients younger than 6 months of age treated with ETV and assessed its feasibility as a first choice of treatment for hydrocephalus.

Methods: Between 1994 and 2008 in our clinic, 23 patients younger than 6 months having presented with obstructive hydrocephalus were treated endoscopically. The etiology of hydrocephalus was congenital aqueduct stenosis in 11 patients, posthemorrhagic obstruction in six patients, myelomeningocele in two patients, postmeningitis in two patients, Chiari I malformation in one patients, and Dandy Walker variant in one patient. ETV was considered successful when no shunt operation was needed in the patient.

Results: ETV was successful in eight patients with regression of intracranial hypertension. In the remaining 15 patients ventriculoperitoneal shunt implantation was necessary. Total success rate in our group of patients was 34.8%. In patients younger than 3 months of age (n=12), success rate was 25.0%. In patients from 3 to 6 months of age (n=11), success rate was 45.5%. Complication included intraventricular hemorrhage in one patient, meningitis and cerebrospinal fluid leak in one patient, and meningitis in one patient.

Conclusions: Based on our experience, ETV could be the first method of choice for hydrocephalus in children younger than 6 months of age, especially in patients older than 3 months of age.

Is the routine placement of a CSF reservoir following endoscopic third ventriculostomy justified?

British Journal of Neurosurgery,23:5,521-523. DOI: 10.1080/02688690902980849

Endoscopic third ventriculostomy (ETV) is a well established treatment for selected cases of obstructive hydrocephalus. However, it does carry a significant rate of failure, which can be abrupt and life threatening. The present study analyses the benefits versus the risks of routine CSF reservoir insertion during ETV. Clinical data obtained from the medical records of patients from a single neurosurgical centre who underwent ETV between August 2002 and February 2007 were analysed retrospectively. A total of 34 records were available with follow-up ranging from 3–56 months (Median 26 months) and with patient age range between 6 months – 75 yrs (median 19 years). During this period, one neurosurgeon routinely placed reservoirs in all patients undergoing ETV (n1/434). In all instances of reservoir insertion, Ommaya reservoirs were used. The number of patients in which the reservoir was tapped for diagnostic and/or therapeutic reasons was quantified, and all complications resulting from reservoir placement recorded. ETV success was defined by a lack of subsequent need for cerebrospinal fluid diversion. In total 13 of 34 (38%) reservoirs inserted were tapped at a later date and there were no complications associated with their insertion. Tapping of reservoirs helped determine which patients required subsequent ventriculoperitoneal (VP) shunting. In at least one case reservoir tapping was carried out as an emergency and was a crucial intermediate intervention prior to further surgery. The overall success rate of ETV was 65% (95% CI, 49–81%) with four complications associated with ETV: short-term memory loss, psychosis, and two cases of post-operative seizures. These complications were not attributed to CSF reservoir insertion but the ETV procedure itself. The routine placement of CSF reservoir following ETV thus seems justified with respect to the observed benefits and lack of complications associated with its placement.


Effect of spinal cord signal intensity changes on clinical outcome after surgery for cervical spondylotic myelopathy

J Neurosurg Spine 11:562–567, 2009.DOI: 10.3171/2009.6.SPINE091

The presence of intramedullary T2 high signal intensity changes in patients with cervical spondylotic myelopathy (CSM) indicates the existence of a chronic spinal cord compressive lesion. However, the prognostic significance of signal intensity changes remains controversial. The purpose of this study was to evaluate the effect of spinal cord T2 signal intensity changes on the outcome after surgery for CSM.

Method. In a prospective study, 64 patients with CSM who underwent surgical treatment between October 2006 and April 2008 using an anterior approach were included. Based on the clinical symptoms and signs present, the severity of neurological deficits of all patients was scored according to a modified Japanese Orthopaedic Association scale score for CSM just before the surgery and at 6 months follow-up. Recovery rates were calculated at 6 months.

Results. There were 22 patients who did not have spinal cord intensity changes on MR imaging and 44 who demonstrated high-intensity signal changes on T2-weighted images (focal or segmental). No statistically significant differences were found in recovery rates between cases with T2 signal intensity changes and those with no signal intensity changes. However, the postoperative modified Japanese Orthopaedic Association scale scores and the recovery rates were much lower in patients with multisegmental signal intensity changes compared with those without these changes or those with focal signal intensity change, and ANOVA demonstrated this difference to be statistically significant (p < 0.05).

Conclusion. Multisegmental spinal cord signal intensity changes on T2-weighted MR imaging are predictors of a poor outcome in terms of functional recovery rate in patients undergoing operations for CSM.

ABC Surgical Risk Scale for skull base meningioma

J Neurosurg 111:1053–1061, 2009.DOI: 10.3171/2007.11.17446

Surgery for skull base meningiomas (SBMs) can lead to complications because these lesions are difficult to approach and can involve cranial nerves and arteries. The authors propose a scoring system to evaluate the relative risks and benefits of surgical treatment of SBMs.

Methods. The authors used a 2-step process to construct their scale. First, they derived significant predictive variables from retrospective data on 132 SBM cases treated surgically (primary surgeries only) between May 2000 and December 2005. Next, they validated the predictive accuracy of their scoring system in 60 consecutive cases treated surgically between January 1995 and April 2000, including both primary and repeated surgeries. Finally, they investigated the effect of the surgery on the patients’ preoperative symptoms for consecutive cases treated surgically between January 1995 and December 2005, including both primary surgeries and retreatments.

Results. Five items that predicted surgical risk were identified: 1) tumor attachment size; 2) arterial involvement; 3) brainstem contact; 4) central cavity location; and 5) cranial nerve group involvement. The authors named their scoring system the ABC Surgical Risk Scale, after the initial letters of these items. Each factor was assigned a score of 0–2 points, and an additional point was added for previous surgical treatment or for radiation, giving a possible total score of 12 points. On average, the scoring system allocated 2 points for gross-total resections, 6.1 points for near-total resections, and 9 points for subtotal resections, with significant differences between groups. For cases scoring ≥ 8 points, the percentage of cases showing neurological deterioration postoperatively exceeded the percentage showing improvement.

Conclusions. The authors conclude that this scoring system can be used to predict the extent of tumor removal and that the scores reflect the surgical risk.


Cerebral Hemodynamic Changes in Severe Head Injury Patients Undergoing Decompressive Craniectomy

J Neurosurg Anesthesiol 2009;21:339–345

A prospective study was carried out on 26 TBI patients, measuring transcranial Doppler and ICP before, immediately after, and 48 hours after the DC, allowing for statistical analysis of hemodynamic changes. The mortality rate and the neuro- logical outcomes were assessed.

Measurements and Results: After DC, ICP decreased from 37±17 to 20±13mm Hg (P=0.0003). The global cerebral blood flow was modified with diastolic velocities rising from 23±15 to 31±13cm/s (P=0.0038) and a pulsatility index decreasing from 1.70±0.66 to 1.18±0.37 (P=0.0012). This normalization of the global cerebral hemodynamics after the DC was immediate, symmetric, and constant during the first 48 hours. Outcome was evaluated at 6 months: good recovery or moderate disability was observed in 11 patients (42%), persistent vegetative state in 7 patients (27%), and 8 patients died (31%).

Conclusions: The DC results in a significant, immediate, and durable improvement of ICP associated with a normalization of cerebral blood flow velocities in most TBI patients with refractory intracranial hypertension.

Cervical spondylotic myelopathy associated with kyphosis or sagittal sigmoid alignment: outcome after anterior or posterior decompression

J Neurosurg Spine 11:521–528, 2009. DOI: 10.3171/2009.2.SPINE08385

The effects of sagittal kyphotic deformities or mechanical stress on the development of cervical spondylotic myelopathy, or the reduction and fusion of kyphotic sagittal alignment have not been consistently documented. The aim in this study was to determine the effects of kyphotic sagittal alignment of the cervical spine in terms of neurological morbidity and outcome after 2 types of surgical intervention.

Methods. The authors retrospectively reviewed the records of 476 patients who underwent cervical spine surgeries for spondylotic myelopathy between 1993 and 2006 at their university medical center. Among these were identified 43 patients—30 men and 13 women, with a mean age of 58.8 years—who had cervical kyphosis exceeding 10° on preoperative sagittal lateral radiographs obtained in the neutral position, and their cases were analyzed in this study. Anterior decompression with interbody fusion was conducted in 28 patients, and en bloc open-door C3–7 laminoplasty in 15 patients. Both pre- and postoperative neurological, radiographic, and MR imaging findings were assessed in both surgical groups.

Results. The mean preoperative kyphotic angle in all 43 patients was 15.9 ± 5.9° in the neutral position. Seg- mental instability was noted in 26 patients (61%) and reversed dynamic spinal canal stenosis at the level above the local kyphosis in 22 (51%). Preoperative T2-weighted MR images showed high-intensity signal within the cord at and around the level of maximal compression or segmental instability in 28 patients (65%). The mean kyphotic angle in both the neutral and flexion positions was significantly smaller at 4–6 weeks after surgery in the anterior spondylectomy group than in the laminoplasty group (p < 0.001). Furthermore, the angle in the neutral position was significantly smaller on follow-up in the anterior spondylectomy group than in the laminoplasty group (p = 0.034). The transverse area of the spinal cord was significantly larger in the anterior spondylectomy group than in the lamino- plasty group on follow-up (p = 0.037). Preoperative neurological scores (assessed using the Japanese Orthopaedic Association scale) and improvement on follow-up ≥ 2 years after treatment (average 3.3 years) were not significantly different between the 2 groups; however, there was a significant difference in Japanese Orthopaedic Association score at 4–6 weeks postoperatively (p = 0.047).

Conclusions. Kyphotic deformity and mechanical stress in the cervical spine may play an important role in neurological dysfunction. In a select group of patients with kyphotic deformity ≥ 10°, adequate correction of local sagittal alignment may help to maximize the chance of neurological improvement

Limits of endoscopic treatment of sylvian arachnoid cysts in children

Childs Nerv Syst. DOI 10.1007/s00381-009-0977-5

The optimal surgical management of sylvian arachnoid cysts is debated. We present our experience in children who were treated endoscopically, focusing on the limits and complications of this approach.

Materials and methods: Seventeen children with a temporo- sylvian arachnoid cyst have been treated using a purely temporal endoscopic approach.

Results: In all but one case, the recognition of anatomical landmarks was obtained at the insertion of the endoscope. In one child, the orientation and opening of the basal cisterns were more difficult due to the thickness and opacity of the membranes. Nevertheless, it was possible to perform the cysto-cisternostomy endoscopically in all children with several stomies in 13. In one child, a venous bleeding occurred. There were no other intraoperative complications. There were no postoperative cerebrospinal fluid leaks. In two patients, a symptomatic subdural collection developed which required a transient subdural-peritoneal shunt. No subdural collection was noted on a delayed follow-up (mean, 23 months). Preoperative symptoms related to the mass effect exerted by the cyst resolved in all children. Two children presented a recurrence, 12 and 20 months after endoscopic surgery, respectively. At the redo-endoscopy, the stomies were found to be closed. Their reopening resulted in the disappearance of the symptoms.

Conclusions: An endoscopic approach can be used safely in the management of sylvian arachnoid cysts. An effective opening of the deep arachnoid membranes into the basal cisterns could be performed in all patients with the resolution of the preoperative symptoms. However, the long-term efficacy of the stoma needs to be assessed.

Intraoperative mapping and monitoring of brain functions for the resection of low-grade gliomas

Neurosurg Focus 27 (4):E4, 2009. (DOI: 10.3171/2009.8.FOCUS09137)

Low-grade gliomas ([LGGs] WHO Grade II) are slow-growing intrinsic cerebral lesions that diffusely infiltrate the brain parenchyma along white matter tracts and almost invariably show a progression toward malignancy. The treatment of these tumors forces the neurosurgeon to face uncommon difficulties and is still a subject of debate. At the authors’ institution, resection is the first option in the treatment of LGGs. It requires the combined efforts of a multidisciplinary team of neurosurgeons, neuroradiologists, neuropsychologists, and neurophysiologists, who together contribute to the definition of the location, extension, and extent of functional involvement that a specific lesion has caused in a particular patient. In fact, each tumor induces specific modifications of the brain functional network, with high interindividual variability. This requires that each treatment plan is tailored to the characteristics of the tumor and of the patient. Consequently, surgery is performed according to functional and anatomical boundaries to achieve the maximal resection with maximal functional preservation. The identification of eloquent cerebral areas, which are involved in motor, language, memory, and visuospatial functions and have to be preserved during surgery, is performed through the intraoperative use of brain mapping techniques. The use of these techniques extends surgical indications and improves the extent of resection, while minimizing the postoperative morbidity and safeguarding the patient’s quality of life.

In this paper the authors present their paradigm for the surgical treatment of LGGs, focusing on the intraoperative neurophysiological monitoring protocol as well as on the brain mapping technique. They briefly discuss the results that have been obtained at their institution since 2005 as well as the main critical points they have encountered when using this approach.

Removal of giant extraforaminal dumbbell tumors of cervical spine

The Spine Journal 9 (2009) 822–829. doi:10.1016/j.spinee.2009.06.023

Removal of cervical dumbbell tumors can be particularly challenging because of unique exposure requirements and proximity of the vertebral artery (VA). There are no reports describing the treatment of giant cervical spine dumbbell tumors (CSDTs).

PURPOSE: To introduce an extensive posterolateral approach to CSDTs involving total lateral mass resection and laminectomy.

STUDY DESIGN: Prospective study of all the patients with multilevel CSDTs treated by  this new procedure between December 2002 and March 2006.

PATIENT SAMPLE: Sixteen patients (3 men and 13 women) with CSDTs underwent the procedure we describe. The follow-up periods ranged from 9 to 51 months (average 9 months). Average age at surgery was 45 years (range 23–68 years).

OUTCOME MEASURES: Axial symptoms and Japanese Orthopedic Association scores were recorded. Pre- and postoperative ranges of neck motion were measured on lateral flexion and extension radiographs.

METHODS: After making a midline incision, we preferred exposing the extraforaminal component of the tumor before performing a semilaminectomy and lateral mass resection. Any lateral extensión of a tumor can be attained by detachment of the adjacent three or more segments of the lateral mass muscle insertion. The most lateral portion can be separated beneath the tumor’s superficial muscle flap, and then when the tumor is retracted medially, the whole portion of the lateral component can be totally exposed. We then performed total lateral mass resection and laminectomy to expose the tumor at the foramina and cervical canal.

RESULTS: We were able to completely resect the tumors in every patient. The average duration of surgery was 150 minutes. Blood loss was minimal (average 400 mL). All patients were monitores for a minimum of 9 months (range 9–51 months; mean 28 months). The follow-up period was uneventful, and no patients developed spinal instability.

CONCLUSIONS: Extensive posterolateral exposure enables surgeons to reach the lateralmost portion of CSDTs and also facilitates septation of the VA and resection of vertebral body encroachment of the tumor.


Foramen magnum meningiomas: experiences in 114 patients

Surgical Neurology 72 (2009) 376–382. doi:10.1016/j.surneu.2009.05.006

Background: Although 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.
Methods: We reviewed 114 consecutive cases of FMM operated between May 1993 and June 2008 in the neurosurgery department at Beijing Tiantan Hospital.
Results: There 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).
Conclusion: Our 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.

Outcome After Anterior Cervical Discectomy and Arthrodesis A Clinical Study of 368 Patients

Neurosurg Q 2009;19:164–170

Aim: To define the predictors for the clinical outcome after anterior cervical discectomy and arthrodesis for patients with degenerative diseases of the cervical spine. Does the subsidence of the intervertebral spacer in the adjacent vertebral have a negative influence on the outcome?
Materials and Methods: In a prospective clinical study, 368 patients underwent anterior cervical discectomy and arthrodesis with degenerative disease of the cervical spine. The patients were treated between September 1997 and January 2005. All patients were followed up 1 year after surgery.
Results: Young age of the patient, mono-segmental anterior cervical discectomy and arthrodesis of the lower cervical spine are predictors of a satisfactory outcome. We did not find statistical differences in the outcome between male and female patients or between patients with or without subsidence of the cage.
Conclusions: Good results can be achieved by early operative therapy. The subsidence of the cage does not affect the outcome.

Intracranial-intracranial arterial by-pass for complex aneurysms

Neurosurgery 65:670–683, 2009 DOI: 10.1227/01.NEU.0000348557.11968.F1

OBJECTIVE: Bypass surgery for brain aneurysms is evolving from extracranial-intracranial
(EC-IC) to intracranial-intracranial (IC-IC) bypasses that reanastomose parent arteries,
revascularize efferent branches with in situ donor arteries or reimplantation, and reconstruct bifurcated anatomy with grafts that are entirely intracranial. We compared results with these newer IC-IC bypasses to conventional EC-IC bypasses.
METHODS: During a 10-year period, 82 patients underwent bypass surgery as part of their aneurysm management. A quarter of the patients presented with ruptured aneurysms and two-thirds presented with compressive symptoms from unruptured aneurysms. Most aneurysms (82%) had non-saccular morphology and 56% were giant sized. Common locations included the cavernous internal carotid artery (23%), middle cerebral artery (20%), and posteroinferior cerebellar artery (12%).
RESULTS: Forty-seven patients (57%) received EC-IC bypasses and 35 patients (43%)received IC-IC bypasses, including 9 in situ bypasses, 6 reimplantations, 11 reanastomoses, and 9 intracranial grafts. Aneurysm obliteration rates were comparable in ECIC and IC-IC bypass groups (97.9% and 97.1%, respectively), as were bypass patency rates (94% and 89%, respectively). Three patients died (surgical mortality, 3.7%), and 4 patients were permanently worse as a result of bypass occlusions (neurological morbidity,4.9%). At late follow-up (mean duration, 41 months), good outcomes (Glasgow Outcome Scale score 5 or 4) were measured in 68 patients (90%) overall, and were similar in EC-IC and IC-IC bypass groups (91% and 89%, respectively). Changes in Glasgow Outcome Scale score were slightly more favorable with IC-IC bypass (6% worse or dead after IC-IC bypass versus 14% with EC-IC bypass).
CONCLUSION: IC-IC bypasses compare favorably to EC-IC bypasses in terms of aneurysm obliteration rates, bypass patency rates, and neurological outcomes. IC-IC bypasses can be more technically challenging to perform, but they do not require harvest of extracranial donor arteries, spare patients a neck incision, shorten interposition grafts, are protected inside the cranium, use caliber-matched donor and recipient arteries, and are not associated with ischemic complications during temporary arterial occlusions. IC-IC bypass can replace conventional EC-IC bypass with more anatomic reconstructions for selected aneurysms involving the middle cerebral artery, posteroinferior cerebellar artery, anterior cerebral artery, and basilar apex.

Meningiomas of the ventral foramen magnum and lowerclivus

Acta Neurochir DOI 10.1007/s00701-009-0511-2

Purpose To identify an appropriate surgical approach for meningiomas of the foramen magnum and lower clivus and determine the factors influencing the surgical outcomes. Method The study involved 23 patients with foramen magnum or lower clival meningiomas (8 men, 15 women; average age, 56 years; range, 26–70 years) treated at Keio University Hospital between 1991 and 2008. Their clinical data were retrospectively reviewed with regard to the surgical approaches and outcomes. The average follow-up duration was 42.8 months, the mean tumour size, 25.9 mm (range, 12.0–50.0 mm).

Findings The tumours most commonly originated in the anterolateral rim of the foramen magnum. In 12 cases with lateral compression of the brain stem, the tumours were resected via the suboccipital approach with C1 laminectomy. The transcondylar approach was adopted in 11 cases where the tumour was located on the anterior rim of the foramen magnum. Four patients required epidural drilling of the jugular tubercle. Gross total resection was achieved in 15 cases (62.5%), the resection rate being lowest in cases of tumour extension to the lower clivus. The transient and permanent morbidity rates were 30.4% and 17.4%, respectively. Logistic regression analysis revealed that extension to the lower clivus (noted in 6 of 23 patients) was a statistically significant, independent factor influencing the permanent morbidity rate (p = 0.005)

Conclusions Selecting an appropriate surgical approach considering the tumour location resulted in a good surgical outcome. However, tumour extension to the lower clivus strongly influenced the morbidity and tumour radicality

Endoscopic treatment of third ventricular colloid cysts

Neurosurg Rev (2009) 32:395–402. DOI 10.1007/s10143-009-0208-2

The surgical treatment of colloid cysts has been traditionally difficult with high rate of postoperative complications. The variety of surgical options reflects the technical difficulty in removing these benign lesions with low morbidity. Microsurgical removal has for years been considered the “gold standard” of treatment, with the use of either a transcortical–transventricular or a transcallosal approach. Neuroendoscopic management is emerging as a safe, effective alternative to microsurgery. The present review discusses the role

of endoscopy in the surgical treatment of third ventricular colloid cysts focusing on some factors, which might influence the outcome. The results have been presented from the literature and supplemented by the results of treating ten personal cases of third ventricular colloid cysts who were operated endoscopically in the Neurosurgical Department, Cairo University. This study aims at evaluating the endoscopic approach as a surgical line of treatment in the management of third ventricular colloid cysts and to see if it has already become superior over microsurgery.

Conclusions: Endoscopic approach to third ventricular colloid cysts is a minimally invasive procedure, which achieves both total evacuation of the cyst and at least near-total resection of the cyst wall with a low surgical morbidity. The available results document less radical excisions as compared to microsurgical group; this is counterbalanced by the lower incidence of complications and shorter operative, hospitalization, and rehabilitation time in the endoscopic group. This conclusion makes endoscopy an alternative and not a better choice than microsurgery. Consequently, the ongoing debate between both procedures remains unresolved. This dispute will become resolved only when long-term studies (mean follow-up for 10 years or greater) are available for a substantial number of patients who have undergone endoscopic resection.

Dura splitting decompression in Chiari type 1 malformation: clinical experience and radiological findings

Neurosurg Rev (2009) 32:465–470. DOI 10.1007/s10143-009-0214-4

To restore the cerebrospinal fluid (CSF) flow at the craniocervical junction in Chiari I malformation (CM-I), most surgeons practice a suboccipital craniectomy with duraplasty. To reduce the risk of CSF leak, a dura splitting decompression is created removing only the dural outer layer. We report on a series of 11 patients with CM-I (five with syringomyelia) operated on between 2000 and 2007 using this technique. Neurological examination and cerebro-spinal MRI scan were performed before and after surgery. Symptoms improved completely in six patients. Headaches and cervicalgias disappeared for all patients. Dizziness and paresthesia in the upper limb remained unchanged for three and two patients, respectively. We observed no complications such as CSF leak, meningocele, or meningitis. Postoperative MRI scan showed a significant craniocervical decompression in ten patients. Four patients had a new cisterna magna. Two syringomyelias completely disappeared, two decreased, and one was stable. Dural splitting can be practiced to treat CM-I. Clinical results are similar to the other techniques with less complications. Radiological findings show satisfying posterior fossa decompression.