Surgery on anterior foramen magnum meningiomas using a conventional posterior suboccipital approach: a report on an experience with 17 cases.

OBJECTIVE: The advantages of a posterior "conventional" suboccipital approach with a midline incision over lateral, anterolateral, and anterior approaches to anteriorly placed foramen magnum meningiomas are discussed. METHODS: From 1991 to March 2000, 17 patients with foramen magnum meningiomas arising from the anterior or anterolateral rim of the foramen magnum underwent operations in the Department of Neurosurgery at King Edward Memorial Hospital and Seth G.S. Medical College. All patients were operated on in a semi-sitting position by use of a conventional suboccipital approach with a midline incision and extension of the craniectomy laterally toward the side of the tumor up to the occipital condyle. RESULTS: The patients ranged in age from 17 to 72 years, and the tumors ranged in size from 2.1 to 3.8 cm. The intradural vertebral artery was at least partially encased on one side in eight patients and on both sides in two patients. The brainstem was displaced predominantly posteriorly in each patient. A partial condylar resection was performed in two cases to enhance the exposure. Total tumor resection was achieved in 14 patients, and a subtotal resection of the tumor was performed in the other 3 patients. In one patient, a small part of the tumor was missed inadvertently, and in the other two patients, part of the tumor in relation to the vertebral artery and posterior inferior cerebellar artery was deliberately left behind. After surgery, one patient developed exaggerated lower cranial nerve weakness. There was no significant postoperative complication in the remainder of the patients, and their conditions improved after surgery. The average length of follow-up is 43 months, and there has been no recurrence of the tumor or growth of the residual tumor. CONCLUSION: From our experience, we conclude that a large majority of anterior foramen magnum meningiomas can be excised with a lateral suboccipital approach and meticulous microsurgical techniques.     

Supraorbital keyhole approach for removal of midline anterior cranial fossa meningiomas: a series of 20 consecutive cases

The paper describes a retrospective study of a consecutive series of 20 midline anterior cranial fossa meningiomas (five of the olfactory groove, 14 of the tuberculum sellae, and one clinoidal), which were operated on via a supraorbital keyhole approach between 2002 and 2008. The series includes three males and 17 females (mean age 57 years, mean size of the tumors 3.5 × 3 cm, and mean follow-up 48 months). Gross total excision was achieved in 18 cases and subtotal resection in two. Out of 14 patients with visual deficits, nine patients improved, one remained stable, and three deteriorated. Two patients presented a recurrence 3 years after surgery. One peri-operative death was recorded. The subgroup of patients with tuberculum sellae meningiomas was analyzed in details. A meta-analysis of the major series of such meningiomas in the last 20 years has been performed in order to compare results of different surgical techniques. With regard to primary outcomes of these tumors, gross total removal, restoration of visual function, morbidity, mortality, and recurrence rates, the supraorbital approach, for selected cases, seems to offer valuable results, comparable with those reported in conventional and endoscopic approaches and with very low surgical aggressiveness. However, statistical data available from the literature, particularly on visual function, are still too limited to draw definitive conclusions. The best surgical option for the individual patient cannot yet be standardized and should be chosen on the basis of tumor anatomy, pre-operative clinical symptoms, and surgeon’s experience.     

Intraventricular meningiomas: a consecutive series of 22 patients and literature review

Intraventricular meningiomas (IVMs) are rare tumors of which the majority is located in the lateral ventricles. Most published series on the subject includes only a few patients. We analyzed our series of IVMs with a special interest in clinical features, outcome, and complications related to surgery. Twenty-two patients underwent resection of IVMs from 1990 to 2010 at Oslo University Hospital. Surgical and medical records were retrospectively analyzed. The IVMs were located in the trigonum of the lateral ventricles (20/22), in the third ventricle (1/22), and in the fourth ventricle (1/22). The most common symptoms and signs were headache, vertigo, nausea/vomiting, mental disturbances, balance impairment, and corticospinal tract signs. Visual field deficit was present preoperatively in two patients. Tumors of the lateral ventricles were resected via a transcortical parieto-occipital approach; the tumors in the third and fourth ventricle via a frontal transcortical and suboccipital route, respectively. Complete tumor resection was achieved in all but one case. Histology was WHO grade I in 20/22 and grade II in 2/22. Surgical mortality was 0 %. Most symptoms and signs resolved after surgery. The most common complication was visual field defect: four patients developed new-onset contralateral homonymous quadrant anopia and one patient developed hemianopia. Symptomatic IVMs should be resected, and most symptoms and signs resolve after surgery. The main challenge is to avoid damaging the geniculucalcarine tract when resecting IVMs in the trigonum. Preoperative diffusion tensor imaging-based tractography to map the geniculocalcarine tract could be a useful adjunct in the preoperative planning before selecting the surgical approach.     

Surgical management of ventral and ventrolateral foramen magnum meningiomas: report on a 64-case series and review of the literature

Foramen magnum meningioma poses a challenge for neurosurgeons. Prognosis has generally improved with diagnostic and surgical advances over the past two decades; however, it may ultimately depend more on the surgeon's ability to tailor the approach and interpret intraoperative risks in single cases. The series comprised 64 patients operated on for ventral and ventrolateral foramen magnum meningioma. All patients underwent preoperative magnetic resonance imaging and received surgery via the dorsolateral route, rendering the series homogeneous in neuroradiological workup and surgical treatment. Particular to this series was that the majority of patients were of advanced age (n?=?29; age, >65 years), had serious functional impairment (n?=?30, Karnofski score <70), and large tumors (mean diameter, 3.5 cm). Total tumor removal was achieved in 52 (81 %) patients; operative mortality was nil. Early outcome varied depending on difficulties encountered at surgery (cranial nerve position and type of involvement in particular) and type of preoperative dysfunction. Long-tract signs and cerebellar deficits improved in 74 and 77 % of cases, respectively, but only 27 % of cranial nerve deficits did so. Surgical complications most often involved the cranial nerves: cranial nerve impairment, especially of the 9th through the 12th cranial nerves, due to stretching or encasement was noted in 44 cases. At final outcome assessment, two thirds of the cranial nerve deficits cleared, and all but two patients returned to a normal productive life. One patient was reoperated on during the follow-up period. Foramen magnum meningiomas behave like clival or spinal tumors depending on their prevalent extension. A dorsolateral approach tailored to tumor position and extension and meticulous surgical technique allow for definitive control of surgical complications. Scrupulous postoperative care may prevent dysphagia, a major persistent complication of surgery. Long-term observation of indolent tumor behavior at follow-up suggests that incomplete resection may be a viable surgical treatment option.     

Amyand’s hernia: a report of 18 consecutive patients over a 15-year period

Aim The presence of a vermiform appendix in an inguinal hernia sac is termed Amyand’s hernia. It may present as a tender inguinal or inguino-scrotal swelling and is often misdiagnosed as an incarcerated or strangulated hernia. The purpose of this study was to review the management of Amyand’s hernia at a single institution since 1991. Material and methods A retrospective analysis was undertaken of 18 consecutive patients with an Amyand’s hernia operated upon at our institution from 1991 to 2005. Patients’ demographics, treatment and postoperative outcome were analysed. Results There were 17 men and one woman. Their median age was 42 years. None of the patients was diagnosed preoperatively. The commonest presenting symptom was painful inguinal or inguino-scrotal swelling (83%). All patients, therefore, underwent emergency surgery with a presumptive diagnosis of either incarcerated or strangulated inguinal hernia. Operative findings included 11 normal appendices, four inflamed appendices and three perforated appendices in the inguinal hernial sac. Patients with a normal appendix (n = 11) had a mesh hernia repair without an appendicectomy. The rest of the patients (n = 7) with an abnormal appendix underwent emergency open appendicectomy followed by Bassini’s sutured hernia repair. One patient died in the postoperative period of pneumonia. Only one recurrent hernia has been detected, with a median follow-up time of 6.4 years. Conclusion The inflammatory status of the appendix determines the type of hernia repair and the surgical approach. Incidental appendicectomy in the case of a normal appendix is not favoured.     

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.     

Ventral foramen magnum neurenteric cysts: a case series and review of literature

Neurenteric cysts (NEC) are uncommon, benign, congenital lesions. Ventral foramen magnum (FM) location is very rare. The difficulties in diagnosis and management aspects are detailed with a review of the pertinent literature. We report four new cases of ventral FM NEC, all managed surgically and present a literature review of ventral FM NEC. A retrospective analysis of histopathologically confirmed cases of ventral FM NEC, operated from 2010–2013 at our institute, was performed. For review, only those cases of NEC extending from the lower clivus to the C2 level constituting the foramen magnum were included. Including our four cases, a total of 47 cases were identified. The male to female ratio was 1.2:1. Mean age was 33.5 years (range 1–60 years). Neck pain and occipital headache were the most common symptoms, followed by limb weakness and cranial nerve paresis. Recurrent meningitis was noted in three cases. Hyperintensity on both T1- and T2-weighted sequences with absent enhancement was the most common finding on MRI. Surgical approaches were as follows: suboccipital (n?=?21), far/extreme lateral (n?=?18), retrosigmoid (n?=?6), and transoral (n?=?4). The extent of resection was as follows: total, 26; near total, 6; subtotal, 9; and partial, 3 cases. Cerebrospinal fluid diversion was done in four cases for intracranial hypertension. Mean follow-up duration was 26.8 months (range 1 month–9 years). Recurrence was noted in four (8.5 %) cases. One (2 %) case had malignant transformation. Mortality rate was 4 %. Foramen magnum neurenteric cysts are rare, benign tumors of the central nervous system. Accurate preoperative diagnosis can often be established with MRI. Surgical removal is the treatment of choice. Complete excision is ideal but often not possible. Near total removal would suffice with good progression-free periods. A long-term follow-up with radiological studies is necessary as delayed recurrences can occur.     

The midline suboccipital subtonsillar approach to the hypoglossal canal: surgical anatomy and clinical application

Summary Primary lesions of the hypoglossal canal, such as hypoglossal schwannomas, are rare. No consensus exists with regard to the surgical approach of choice for treatment of these lesions. Usually, lateral transcondylar approaches have been used. The authors describe the surgical anatomy of the midline subtonsillar approach to the hypoglossal canal. This approach includes a midline suboccipital craniotomy, dorsal opening of the foramen magnum and elevation of ipsilateral cerebellar tonsil to expose the hypoglossal nerve and its canal. The midline subtonsillar approach permits a straight primary intradural view to the hypoglossal canal. There is no necessity of condylar resections. The surgical anatomy of the subtonsillar approach is described and illustrated by an example of a case.     

Vertebro-PICA aneurysms: midline suboccipital approach and laminectomy of the atlas

Vertebro-PICA aneurysms represent a particular technical challenge because of the extremely narrow operative field and the presence of numerous vital neural and vascular structures. The lack of exposure still remains the limiting factor in most cases. During the 9-year period from January 1980 to October 1989, 8 vertebro-PICA aneurysms have been treated microsurgically. Of these, 2 underwent a pure suboccipital approach while 6 underwent a midline suboccipital approach with deliberate removal of the arch of the atlas in the park bench position. Seven patients did well and regained full activities while one patient died from complications related to vasospasm with brainstem infarction. One patient developed symptomatic obstructive dilation of the fourth ventricle requiring ventriculo-cisternostomy. The authors recommend the midline suboccipital approach with deliberate C1-laminectomy in ventrolateral decubitus for vertebro-PICA aneurysms. The main advantages are: constant access to the proximal vertebral artery, less medullary retraction in ventrally located aneurysms, improved exposure of the laterobulbar cisterns and the lateromedullary and tonsillar segments of the PICA, thus facilitating dissection of the aneurysm.     

Gamma Knife radiosurgery for tuberculum sellae meningiomas: a series of 78 consecutive patients

Neurosurgical Review - Outcomes of Gamma Knife radiosurgery (GKRS) for tuberculum sellae meningiomas (TSMs) have not been reported explicitly within any meningioma series. We present the first and...     

Anesthesia-related mortality and morbidity over a 5-year period in 2,363,038 patients in Japan

BACKGROUND: Statistical data of mortality and morbidity related to anesthesia have not been reported in Japan since World War II. The need to comprehensively examine the events of cardiac arrest as well as mortality prompted the first national study in Japan. METHODS: Confidential questionnaires were sent to all Japan Society of Anesthesiologists Certified Training Hospitals every year from 1994 through 1998. Collected data were analyzed for incidence of cardiac arrest and other critical events during anesthesia and surgery, and their outcomes within 7 postoperative days. The principal causes of the critical incidents were also analyzed. RESULTS: With an average response rate of 39.9%, a total of 2,363,038 cases were documented over 5 years. The average incidence per year of cardiac arrest during surgery due to all etiologies and that totally attributable to anesthesia was 7.12 [95%CI: 6.30,7.94] and 1.00 [0.88, 1.12]) per 10,000 cases, respectively. The average mortality per year in the operating room or within 7 postoperative days due to all etiologies and that totally attributable to anesthesia was 7.18 [6.22, 8.13] and 0.21 [0.15, 0.27] per 10,000 cases, respectively. The two principal causes of cardiac arrest during anesthesia and surgery due to all etiologies were massive hemorrhage (31.9%) and surgery (30.2%), and those totally attributable to anesthesia were drug overdose or selection error (15.3%) and serious arrhythmia (13.9%). Preventable human errors caused 53.2% of cardiac arrest and 22.2% of deaths in the operating room totally attributable to anesthesia. CONCLUSIONS: The rates in Japan of cardiac arrest and death during anesthesia and surgery due to all etiologies as well as those totally attributable to anesthesia are comparable to those of other developed countries.     

One-day thyroid surgery: retrospective analysis of safety and patient satisfaction on a consecutive series of 1,571 cases over a three-year period

Short-stay thyroid surgery (<24 h hospital stay) is becoming increasingly popular but some potentially lethal complications are considered strong arguments against shortening hospitalization after thyroidectomy. The authors reviewed the data of 1,571 patients undergoing one-day thyroid surgery over a 3-year period to determine safety and patient satisfaction. There were 1,244 females and 327 males. Mean age was 43 years. Patient satisfaction was evaluated by a questionnaire given on discharge, while post-discharge surgical recovery was analyzed by the PSR scale. Total thyroidectomy was performed in 1,119 patients (71%), hemithyroidectomy in 450 (29%), isthmusectomy in 2. Morbidity occurred in 152 patients (9.6%). Surgical complications were transient hypocalcemia in 112 cases and permanent hypoparathyroidism in 3; monolateral transient nerve palsy occurred in 10 cases, bilateral in 3; definitive monolateral recurrent palsy in 4 cases. Bleeding requiring re-intervention occurred in 10 cases, wound complications in 5 cases, and intraoperative tracheal lesion in 1 patient. Among complicated patients, 129 (84.8%) were treated after discharge as outpatients. Conversion to inpatient treatment occurred in 28 patients (1.7%) (25 for surgical reasons). Four patients (0.2%) required hospital readmission. Patients were very satisfied in 84.2%, satisfied in 9.5%, poorly satisfied in 4.3%, completely unsatisfied in 2%. Postoperative recovery mean score by PSR scale resulted in 85.14% (0-100%). Our results confirm that the one-day surgery model is safe, effective, and highly agreeable in patients undergoing surgery for thyroid disease.     

枕下乙状窦后入路在桥小脑角区脑膜瘤中的应用经验

目的探讨枕下乙状窦后入路在桥小脑角区脑膜瘤手术中的作用。方法通过对我院自2001年12月到2015年12月53例采用枕下乙状窦后入路的桥小脑角区脑膜瘤手术病例进行分析,总结分析肿瘤的影像学特点、临床症状、手术疗效及术后神经功能。结果该组病例肿瘤全切48例,次全切除5例。术后症状和体征完全消失32例,症状较术前减轻7例,颅神经损害症状同术前3例,出现新神经功能障11例。结论枕下乙状窦后入路是处理桥小脑角区病变的经典手术入路,该入路可以获得对桥小脑区神经血管良好的暴露,手术创伤小,患者恢复快,术后并发症少。     

Neuroendoscopic approach to tectal tumors: a consecutive series

OBJECT: The authors report a consecutive series of 10 patients who presented with signs and symptoms caused by tectal tumors. Clinical findings, radiographic features, neuroendoscopic management strategies, and histological findings are reported and discussed. METHODS: Since January 1990, 11 neuroendoscopic procedures were performed in 10 patients who harbored tectal tumors. The patients were followed for an average of 5 years (range 2 months-11 years), and a retrospective study was conducted in which case notes, radiological findings, operative notes, and histopathological findings were assessed. Magnetic resonance (MR) imaging was performed, and the images were used to classify patients into three groups: those with hypertrophy of the tectum in whom isointensity appeared on T1-weighted images (Group 1); those with a tectal tumor occupying the cerebral aqueduct in whom decreased signal intensity appeared on T1-weighted images, as well as no enhancement after gadolinium administration (Group 2); and those with a tectal tumor in whom mixed signal intensity and conspicuous evidence of contrast enhancement appeared on T1-weighted images (Group 3). The results of histological examination were consistent with MR imaging features: in Group 1, glial tissue or gliosis; in Group 2, benign astrocytoma; and in Group 3, malignant astrocytoma. Cerebrospinal fluid diversion was the only surgical treatment that provided relief from obstructive hydrocephalus. One patient in Group 3 underwent radiotherapy and subsequent partial tumor removal under neuroendoscopic guidance. Thereafter, the tumor remained in decline. All patients had normal intellectual status after undergoing surgery in which a neuroendoscope was used. CONCLUSIONS: Neuroendoscopic procedures can provide histological diagnosis, define the tumor-midbrain interrelationship, and be highly effective in treating obstructive hydrocephalus and in removing tectal tumors. This procedure may receive clinical application as a new management strategy for tectal glioma.     

Treatment of knee prosthesis infections: evaluation of 15 patients over a 5-year period

Our objective was to evaluate different treatment alternatives for total knee arthroplasty (TKA) infection and to compare outcomes depending on adherence to a current treatment algorithm. All patients treated for a first episode of TKA infection between January 2000 and July 2005 were included. Patient records were reviewed and data were extracted retrospectively. Fifteen patients were followed up for a median of 25 months. The cure rate in patients with two-stage exchange of knee prosthesis was higher than in patients who had débridement without implant removal (100 vs 37%, p = 0.03). Cure rates were not different between these two surgical approaches in ten patients who were treated according to a current treatment algorithm. Success rates for treatment of TKA infections varied considerably with the treatment strategy chosen. Our results support the use of existing algorithms to select patients who are eligible for débridement with retention of the prosthesis or need two-stage exchange of knee implants.