Video article: the subtemporal extradural approach to cavernous sinus tumour.

OBJECTIVE: Here we demonstrate via operative video the subtemporal extradural approach to a tumour in the cavernous sinus. METHODS: The extradural approach is performed here in a paediatric patient (a 15-year-old child) via a right extended pterional osteoplastic craniotomy with removal of the zygomatic arch. The operative microscope is introduced, and the dura is divided at the superior orbital fissure into endosteal and meningeal layers using a diamond knife. The middle cranial fossa floor is drilled flat to increase access, and the plane is further developed towards the cavernous sinus. The tumour is seen bulging from within the cavernous sinus, and the cavernous sinus is opened in the anteromedial triangle between cranial nerves Vi and Vii. After biopsy, the tumour is debulked with an ultrasonic aspirator. Doppler is used to identify the internal carotid artery and preserve it. The bone flap is replaced, and the wound is closed in layers in standard fashion. RESULTS: The patient recovered well and was discharged on post-operative day 3. Persistent sixth nerve palsy (present pre-operatively) was present; however, otherwise, there was good recovery from surgery. Good resection of tumour is demonstrated on post-operative MR imaging. CONCLUSIONS: This approach is uncommon but important as it enables extradural access to the cavernous sinus, minimising the complications associated with an intradural approach such as cortical injury. In this video, we also demonstrate the fundamental anatomy using annotation and cadaveric images to enhance understanding required for the neurosurgeon to successfully complete this approach. The patient consented to the procedure in the standard fashion.

Quantitative and functional visual field outcomes after endoscopic trans-sphenoidal pituitary adenectomy.

OBJECTIVE: Quantitative data on visual outcomes after trans-sphenoidal surgery is lacking in the literature. This study aims to address this by quantitatively assessing visual field outcomes after endoscopic trans-sphenoidal pituitary adenectomy using the capabilities of modern semi-automated kinetic perimetry. METHODS: Visual field area (deg2) calculated on perimetry performed before and after surgery was statistically analysed. Functional improvement was assessed against UK driving standards. RESULTS: Sixty-four patients (128 eyes) were analysed (May 2016-Nov 2019). I4e and I3e isopter area significantly increased after surgery (p < 0.0001). Of eyes with pre-operative deficits: 80.7% improved and 7.9% worsened; the median amount of improvement was 60% (IQR 6-246%). Median increase in I4e isopter was 2213deg2 (IQR 595-4271deg2) and in I3e isopter 1034 deg2 (IQR 180-2001 deg2). Thirteen out of fifteen (87%) patients with III4e data regained driving eligibility after surgery. Age and extent of resection (EOR) did not correlate with visual improvement. Better pre-operative visual field area correlated with a better post-operative area (p < 0.0001). However, the rate of improvement in the visual field area increased with poorer pre-operative vision (p < 0.0001). CONCLUSIONS: A median visual field improvement of 60% may be expected in over 80% of patients. Functionally, a significant proportion of patients can expect to regain driving eligibility. EOR did not impact on visual recovery. When the primary goal of surgery is alleviating visual impairment, optic apparatus decompression without the aim for gross total resection appears a valid strategy. Patients with the worst pre-operative visual field often experience the greatest improvement, and therefore, poor pre-operative vision alone should not preclude surgical intervention.

Prognostic value of leukocytosis in pediatric traumatic brain injury.

OBJECTIVE: The purpose of this study was to assess leukocytosis and its prognostic value in pediatric isolated traumatic brain injury (TBI). METHODS: Two hundred one children with isolated TBI admitted to the authors' institution between June 2006 and June 2018 were prospectively followed and their data retrospectively analyzed. Initial blood leukocyte count (i.e., white cell count [WCC]), Glasgow Coma Scale (GCS) score, CT scans, duration of hospital stay, and Pediatric Cerebral Performance Category Scale (PCPCS) scores were analyzed. RESULTS: The mean age was 4.2 years (range 0.2-16 years). Seventy-four, 70, and 57 patients had severe (GCS score 3-8), moderate (GCS score 9-13), and mild (GCS score 14-15) TBI, respectively, with associated WCC of 20, 15.9, and 10.7 × 109/L and neutrophil counts of 15.6, 11.3, and 6.1 × 109/L, respectively (p < 0.01). Higher WCC and neutrophil counts were demonstrated in patients with increased intracranial mass effect on CT, longer hospital stay, and worse 6-month PCPCS score (p < 0.05). Multivariate regression revealed a cutoff leukocyte count of 16.1 × 109/L, neutrophil count of 11.9 × 109/L, and neutrophil-to-lymphocyte ratio (NLR) of 5.2, above which length of hospital stay and PCPCS scores were less favorable. Furthermore, NLR was the second most important independent risk factor for a poor outcome (after GCS score). The IMPACT (International Mission for Prognosis and Analysis of Clinical Trials in TBI) adult TBI prediction model applied to this pediatric cohort demonstrated increased accuracy when WCC was incorporated as a risk factor. CONCLUSIONS: In the largest and first prospective study of isolated pediatric head injury to date, the authors have demonstrated that WCC > 16.1 × 109/L, neutrophil count > 11.9 × 109/L and NLR > 5.2 each have predictive value for lengthy hospital stay and poor PCPCS scores, and NLR is an independent risk factor for poor outcome. Incorporating the initial leukocyte count into TBI prediction models may improve prognostication.

Chiari I malformation and altered cerebrospinal fluid dynamics-the highs and the lows.

PURPOSE: This paper reviews the altered cerebrospinal fluid dynamics that can be associated with paediatric Chiari I malformation and we present our own institutional experience. METHODS: We conducted a thorough review of the literature and retrospectively analyzed all cases of operatively managed paediatric Chiari 1 malformation at our institution between February 2006 and February 2019. RESULTS: Acquired Chiari malformation (ACM) can radiologically mimic Chiari I and has been associated with both intracranial hypotension (either secondary to lumboperitoneal shunting or spontaneous CSF hypotension) and idiopathic intracranial hypertension (IIH). At our institution, 61 paediatric cases (range, 2-15 years) underwent foramen magnum decompression (FMD) for Chiari I malformation. Whilst 80% (50/61) of cases underwent FMD with no preceding or post-operative problems of CSF dynamics, 8% (5/61) of cases had hydrocephalus at initial presentation requiring CSF diversion followed by FMD for persistent Chiari, and 10% (6/61) developed hydrocephalus following FMD and required long-term CSF diversion. CONCLUSIONS: In paediatric ACM, the management of intracranial hypotension involves thorough radiological assessment and inclusion/adjustment of a valve in the case of lumboperitoneal shunting or epidural blood patch or interventional techniques in the case of spontaneous CSF leak. Thereby, unwarranted posterior fossa decompression surgery is avoided. In the case of IIH and Chiari I malformation, children who have recurrent symptoms despite adequate posterior fossa decompression surgery (failed Chiari), there is a strong role for intracranial pressure monitoring as raised intracranial pressure may indicate long-term CSF diversion.

Outcome and prognostic features in paediatric pineoblastomas: analysis of cases from the Surveillance, Epidemiology, and End Results registry (1990-2007).

BACKGROUND: Paediatric pineoblastomas are rare central nervous system tumours. Patient and treatment factors associated with outcome are poorly defined and limited to small retrospective case series and single case reports. METHODS: Using the Surveillance, Epidemiology, and End Results (SEER) cancer registry, we investigated clinical and pathological factors associated with outcome in paediatric pineoblastomas. Paediatric patients (< 16 years old) with pineoblastomas diagnosed between 1990 and 2007 were identified from the SEER database. Kaplan-Meier survival analysis and Cox models were used to examine the effect of variables on overall survival. The variables analysed included patient's age at diagnosis, gender, race, tumour spread and size, surgical resection and the use of adjuvant radiotherapy. RESULTS: Seventy-eight patients were identified from the database. Twelve patients were excluded as 11 had no surgery and one patient was excluded as the surgical status was unknown. Analysis of the remaining 66 patients revealed a median age at diagnosis of 5.5 years. Three patients underwent biopsy. Seventeen patients underwent full and partial resection, respectively. A further 46 patients underwent surgery the nature of which was not recorded. Thirty-nine patients (59.1%) received adjuvant radiotherapy. Eight patients (12.1%) had both surgery (full or partial resection) and radiotherapy. The median overall survival was 40.5 months. Univariate analysis demonstrated that older age at diagnosis was the only positive predictor of overall survival. CONCLUSION: This study represents the largest analysis of paediatric pineoblastomas to date. The only clinically relevant prognostic factor was older age at diagnosis. The role of surgery and adjuvant radiotherapy on overall survival remains to be defined.

Factors associated with 30-day ventriculoperitoneal shunt failure in pediatric and adult patients.

OBJECTIVE The aim of this study was to provide a comprehensive benchmark of 30-day ventriculoperitoneal (VP) shunt failure rates for a single institution over a 5-year study period for both adult and pediatric patients, to compare this with the results in previously published literature, and to establish factors associated with shunt failure. METHODS A retrospective database search was undertaken to identify all VP shunt operations performed in a single, regional neurosurgical unit during a 5-year period. Data were collected regarding patient age, sex, origin of hydrocephalus, and whether the shunt was a primary or secondary shunt. Operative notes were used to ascertain the type of valve inserted, which components of the shunt were adjusted/replaced (in revision cases), level of seniority of the most senior surgeon who participated in the operation, and number of surgeons involved in the operation. Where appropriate and where available, postoperative imaging was assessed for grade of shunt placement, using a recognized grading system. Univariate and multivariate models were used to establish factors associated with early (30-day) shunt failure. RESULTS Six hundred eighty-three VP shunt operations were performed, of which 321 were pediatric and 362 were adult. The median duration of postoperative follow-up for nonfailed shunts (excluding deaths) was 1263 days (range 525-2226 days). The pediatric 30-day shunt failure rates in the authors' institution were 8.8% for primary shunts and 23.4% for revisions. In adults, the 30-day shunt failure rates are 17.7% for primary shunts and 25.6% for revisions. In pediatric procedures, the number of surgeons involved in the operating theater was significantly associated with shunt failure rate. In adults, the origin of hydrocephalus was a statistically significant variable. Primary shunts lasted longer than revision shunts, irrespective of patient age. CONCLUSIONS A benchmark of 30-day failures is presented and is consistent with current national databases and previously published data by other groups. The number of surgeons involved in shunt operations and the origin of the patient's hydrocephalus should be described in future studies and should be controlled for in any prospective work. The choice of shunt valve was not a significant predictor of shunt failure. Most previous studies on shunts have concentrated on primary shunts, but the high rate of early shunt failure in revision cases (in both adults and children) is perhaps where future research efforts should be concentrated.

The learning curve for endoscopic trans-sphenoidal resection of pituitary macroadenomas. A single institution experience, Leeds, UK.

BACKGROUND: The object of this study was to assess whether increasing operative experience results in greater endoscopic trans-sphenoidal resection of pituitary macroadenomas and lower complications. METHODS: A retrospective single institution cohort study was performed. Subjects underwent endoscopic trans-sphenoidal resection of pituitary macroadenoma between July 2009 and July 2016 by three neurosurgeons. Following data collection, statistical analysis compared percentage of tumor resection and length of hospital stay (LOS) with experience. Complications including CSF leak are reported. RESULTS: In total, 142 patients (87 male, 55 female) mean age 55.1 were included. Surgeon 1 performed 106 cases; surgeon 2 performed 23 cases; and surgeon 3 performed 13 cases. Mean pre-operative tumor volumes were 8.18 cm3, 6.52 cm3, and 3.47 cm3 and post-operative volumes were 2.21, 1.74, and 1.93 cm3 for surgeons 1, 2, and 3, respectively. Respective percentage resections were 74.3, 77.2, and 52.1%. Analysis demonstrated no difference in tumor resection with increasing experience for all three surgeons (p = 0.11, p = 0.17, and p = 0.26). Tumor consistency and cavernous sinus involvement did not appear to affect tumor resection. Mean LOS was 5 days, 4 days, and 3 days, respectively, with no significant correlation with experience for all three surgeons. Intraoperative CSF leak incidence was 19/106 (18%) for surgeon 1, 6/23(26%) for surgeon 2, and 2/13(15%) for surgeon 3. Primary closure rate was 96.3% and only three other complications occurred. CONCLUSIONS: This study demonstrates that in our institution there is no statistically significant learning curve for the endoscopic resection of pituitary macroadenoma. However, there is a trend of improvement in tumor resection with experience for one surgeon. These findings suggest that the surgeons in our institution were capable of performing this procedure effectively with a low complication rate since adoption of the endoscopic technique in 2009.

A rare case of anterior sacral meningocoele presenting as cauda equina syndrome.

The authors present a case of anterior sacral meningocoele demonstrating a clinical picture of cauda equina syndrome. To the best of our knowledge, such presentation has not yet been reported.

Case series of atypical high flow arterio-venous malformations in children.

Arteriovenous malformations (AVM) constitute a clinically significant form of vascular malformations in children. We present three cases of paediatric AVMs that demonstrated unusual features of high flow and significant shunting of blood without a clearly demonstrable nidus. Venous malformations were associated with the lesions. A discussion of the concepts underlying AVM physiology and how these case reports contradict these is included.

Paediatric intramedullary spinal cord cavernous malformations: case report and review of the literature.

Cavernous malformations are vascular lesions which can occur throughout the entire neuraxis. This term is synonymous to cavernous angioma, cavernous haemangioma, and cavernoma. They comprise of closely packed, capillary-like vascular channels, without intervening neural tissue. MR imaging is currently the study of choice for the diagnosis of cavernous malformations as they are considered angiographically occult lesions. Intramedullary location represents only 3-5% of all central nervous system cavernous malformations, with the majority of them being supratentorial. Only 10% of the intramedullary cavernous malformations present in the paediatric population. As the natural history of these lesions is not well known, the debate on the optimal management of them is still ongoing. Here we describe the case of a 14-year-old male with progression of symptoms over an 18 months period, which necessitated microsurgical removal of a T9 intramedullary cavernous malformation.

Patients with autosomal-recessive osteopetrosis presenting with hydrocephalus and hindbrain posterior fossa crowding.

Osteopetrosis is a heterogeneous group of disorders characterized by abnormal bone sclerosis. As a result, patients often require input regarding various neurological complications. Although autosomal-recessive osteopetrosis has been associated with hydrocephalus, it has not been linked to hindbrain abnormalities. The authors present 3 cases of auto-somal-recessive osteopetrosis in patients who presented with hydrocephalus. In each of these patients, cerebrospinal fluid diversion procedures were required and hindbrain compression developed. To date, only 1 patient has needed craniocervical decompression due to symptomatic brainstem compression.

Endoscopic biopsy during third ventriculostomy in paediatric pineal region tumours.

OBJECTS: The goal of the study was to establish if endoscopic biopsy during third ventriculostomy contributes to morbidity in the management of paediatric pineal region tumours presenting with hydrocephalus. MATERIALS AND METHODS: This study was a retrospective descriptive study in patients less than 18 years of age who have presented with a pineal region tumour between 2000 and 2006. Data were obtained from case notes. Twelve patients had presented with a pineal region mass with symptomatic hydrocephalus. Of these, eight had endoscopic biopsy during third ventriculostomy. CONCLUSIONS: No mortality or permanent morbidity was seen following endoscopic biopsy. Two cases of transient worsening of pre-operative diplopia were noted. Diagnostic sensitivity for endoscopic biopsy is 75%. Tumour markers were not significantly raised in any plasma and cerebrospinal fluid samples. Endoscopic biopsy during third ventriculostomy in paediatric pineal region tumours is safe and results in good diagnostic yields. It should play an integral role in the initial management of patients in this setting.

Intracranial hypertrophic calcification complicating neuroendoscopy. Report of three cases.

Three cases are presented in which progressive hypertrophic calcification formed following ventricular endoscopy. After a ventricular endoscopy has been performed, it has been the authors' practice to seal the burr hole with bone dust. They believe that the calcifications formed from bone dust that fell into the track left by the endoscope. This is the first time this complication has been described.