Flexible endoscope-assisted suture release and barrel stave osteotomy for the correction of sagittal synostosis.

OBJECTIVE: Early suturectomy with a rigid endoscope followed by orthotic cranial helmet therapy is an accepted treatment option for single-suture craniosynostosis. To the authors' knowledge, flexible endoscope-assisted suture release (FEASR) has not been previously described. Presented herein is their experience with FEASR for the treatment of isolated sagittal craniosynostosis. METHODS: A retrospective analysis of the health records of patients who had undergone FEASR between March 2018 and December 2020 was performed. Patients under the age of 6 months who had been diagnosed with isolated sagittal synostosis were considered eligible for FEASR. Exclusion criteria included syndromic synostosis or multiple-suture synostosis. The cephalic index, the primary measure of the cosmetic endpoint, was calculated at prespecified intervals: immediately preoperatively and 6 weeks and 12 months postoperatively. Parental satisfaction with the cosmetic outcome was determined throughout the clinical follow-up and documented according to a structured questionnaire for the first 12 months. RESULTS: A total of 18 consecutive patients met the criteria for study inclusion. The mean patient age at the time of surgery was 3.4 months (range 2-6 months). All patients underwent a wide craniectomy with no need to convert to an open procedure. The mean craniectomy width was 3.61 cm. Estimated blood loss ranged from 5 to 30 ml. The mean operative time was 75 minutes. No intraoperative complications were observed. The average length of stay was 2.6 days. The mean cephalic index was 67.7 preoperatively, 77.1 at 6 weeks postoperatively, and 76.3 at 1 year postoperatively. The mean percentage change in the cephalic index from preoperatively to the 12-month follow-up was 10.44 (p < 0.001). The mean follow-up was 17 months (range 12-28 months). All parents were satisfied with the cosmetic outcome of the procedure. No patients developed symptoms of raised intracranial pressure (ICP) or needed invasive ICP monitoring during the follow-up period. No patients required reoperation. CONCLUSIONS: In this modest single-hospital series, the authors demonstrated the feasibility of FEASR in treating sagittal synostosis with favorable cosmetic outcomes. The morbidity profile and resource utilization of the procedure appear similar to those of procedures conducted via traditional rigid endoscopy.

Disseminated Human Subarachnoid Coenurosis.

Background: Traditionally, human coenurosis has been ascribed to Taenia multiceps while neurocysticercosis has been attributed solely to Taenia solium infection. Historically, however, the identification and differentiation of cestodal infection was primarily based on inaccurate morphological criteria. With the increasing availability of molecular methods, the accuracy of identification of the larval cestode species has improved, and cestodal species not typically associated with central nervous system (CNS) infection are now being identified as aetiological agents. Case report: We present a case of a 5-year-old male patient who presented with acute hydrocephalus. Initial MRI revealed multiple cysts in the cerebrospinal fluid (CSF) spaces with a predominance of clumped grape-like cysts in the basal cisterns with resultant acute obstructive hydrocephalus. The child underwent an emergency ventriculo-peritoneal (VP) shunt. A presumptive diagnosis of neurocysticercosis racemosus was made and the child was started on empiric albendazole (15 mg/kg/day) and praziquantel (30 mg/kg/day) treatment, along with concomitant prednisone (1 mg/kg) treatment. Despite prolonged anti-helminthic therapy, the child continued to deteriorate, and endoscopic removal of the 4th ventricular cysts was required. Post-operative MRI revealed radiological improvements, with a reduction in the number and size of cysts, especially in the basal cisterns, with no cysts visualized in the fourth ventricle. DNA was extracted from CSF and cyst tissue using the QiAMP DNA mini kit (Qiagen). The PCR performed on the extracted DNA displayed a band of 275 bp on an agarose gel. The consensus sequence had 97.68% similarity to Taenia serialis 12S ribosomal RNA gene. The child, unfortunately, continued to do poorly, requiring multiple VP shunt revisions for repeated blockage of the VP shunt system, and ultimately demised, despite the 'successful' surgical intervention and continued maximal medical management. Discussion and conclusions: There have been approximately 40 reported cases of human CNS coenurosis, with the assumed etiological agent being confined to T. multiceps. In 2020, the first case of human CNS coenurosis caused by T. serialis was reported. This case involved a single parenchymal lesion in the occipital lobe, which, following complete surgical excision, was confirmed to be T. serialis by mitochondrial gene sequencing. The case we present is the first case of disseminated subarachnoid coenurosis caused by T. serialis. It appears that T. serialis infection can mimic either of the two basic pathological forms of neurocysticercosis, namely, cysticercosis cellulosae or cysticercosis racemosus. We postulate that the term coenurosis racemosus is applicable if CNS T. serialis infection presents with extensive, multiple grape-like bladders proliferating within the subarachnoid space.

Suprasellar arachnoid cyst due to ectopic choroid plexus: case report.

Arachnoid cysts (ACs) are malformations that account for about 1% of all intracranial lesions. The aetiology and progression of these lesions have been debated, with one possible explanation being the production of cerebro-spinal fluid (CSF) by ectopic choroid plexus (CP). To our knowledge, only seven cases of ACs incorporating CP have been reported, and we believe this to be the first reported case of a suprasellar AC containing ectopic CP. A 1-year-old boy presented with developmental delay and macrocephaly. MRI scan revealed hydrocephalus due to a suprasellar AC. An endoscopic ventriculocisternostomy was undertaken. Intra-operatively, intra-cystic, pink frond-like tissue resembling choroid plexus was identified. Histologically, the cyst wall was composed of fibrous tissue, with layered arachnoid cells, while the frond-like tissue was composed of papillary structures in keeping with normal choroid plexus tissue. We postulate that the rest of the ectopic CP may have been trapped within the double layered arachnoid fold of the diencephalic leaf of Liliequist's membrane which may drive the formation and development of certain suprasellar ACs.

Intra-operative monitoring as an adjuvant to standard vagus nerve stimulation implantation.

PURPOSE: The treatment of refractory epilepsy by vagus nerve stimulation (VNS) is a well-established therapy. Complications following VNS insertion may be procedure-related or stimulation-related. Herein, we describe our technique of intra-operative neuro-monitoring (IONM) in an attempt to diminish these adverse events. METHODS: This retrospective study describes 66 consecutive patients between the ages of 3 and 12 years who had undergone primary VNS implantation. The study population consisted of two cohorts, one in which the VNS device was implanted according to the standard described technique and a second group in which IONM was used as an adjuvant during the VNS device placement. Prior to VNS insertion, a Pediatric Voice Handicap Index (PVHI) was performed to assess voice-related quality of life, and this was repeated at 3 months following VNS insertion. RESULTS: Sixty-six patients underwent the VNS implantation. Forty-three patients had a "standard" VNS insertion technique performed, whereas 23 had IONM performed during the VNS implantation. There were significant changes in the PVHI scores across both cohorts at 3-month follow-up. There were no statistically significant differences in PVHI scores between the monitored group and non-monitored group at 3-month follow up. CONCLUSIONS: IONM can be used during VNS insertions to ensure correct placement of the leads on CNX. IONM may minimise vocal cord stimulation by placing the lead coils on the area of nerve eliciting the least amount of vocal cord EMG response. IONM however does not appear to improve voice outcomes at early follow up.

Use of intra-operative stimulation of brainstem lesion target sites for frameless stereotactic biopsies.

INTRODUCTION: Frameless stereotactic navigation is used to direct the trajectory and biopsy site of target lesions. We report on a novel intra-operative stimulating (IOS) probe that is integrated into a commercially available stereotactic biopsy needle with the rationale that stimulation of the intended biopsy site should predict functional tissue thus preventing inadvertent biopsy of eloquent tissue. METHODS: Patients undergoing brainstem biopsies for atypical lesions were offered the additional stimulation procedure. The IOS probe was used to deliver stimulation in an attempt to determine the proximity of eloquent tissue. Once the desired location of the biopsy needle was achieved, the IOS probe was inserted down the centre of the biopsy needle and the stimulus applied. If no action potential was recorded, biopsies from four quadrants of the lesion were taken. If however a compound action potential was recorded, a new target was selected. RESULTS: Nine patients had the biopsy and stimulation procedure performed. The median age was 36 months. A minimum of 8 samples were obtained from each patient. Biopsy material was adequate to obtain a diagnosis in all 9 patients. In 2 cases use of the device influenced the insertion trajectory or biopsy site. No patients experienced any complications directly attributable to either the biopsy procedure or application of the stimulation. CONCLUSIONS: Use of the IOS probe for intra-operative stimulation of the intended brainstem biopsy site was found to be safe and feasible. The addition of stimulation using the IOS probe can be done with minimal change in workflow.

Awake Craniotomy in a Child: Assessment of Eligibility with a Simulated Theatre Experience.

BACKGROUND: Awake craniotomy is a useful surgical approach to identify and preserve eloquent areas during tumour resection, during surgery for arteriovenous malformation resections and for resective epilepsy surgery. With decreasing age, a child's ability to cooperate and mange an awake craniotomy becomes increasingly relevant. Preoperative screening is essential to identify the child who can undergo the procedure safely. Case Description. A 11-year-old female patient presented with a tumour in her right motor cortex, presumed to be a dysembryoplastic neuroepithelial tumour (DNET). We had concerns regarding the feasibility of performing awake surgery in this patient as psychological testing revealed easy distractibility and an inability to follow commands repetitively. We devised a simulated surgical experience to assess her ability to manage such a procedure. During the simulated theatre experience, attempts were made to replicate the actual theatre experience as closely as possible. The patient was dressed in theatre attire and brought into the theatre on a theatre trolley. She was then transferred onto the theatre bed and positioned in the same manner as she would be for the actual surgery. Her head was placed on a horseshoe headrest, and she was made to lie in a semilateral position, as required for the surgery. A blood pressure cuff, pulse oximeter, nasal cannula with oxygen flow, and calf pumps were applied. She was then draped precisely as she would have been for the procedure. Theatre lighting was set as it would be for the surgical case. The application of the monitoring devices, nasal cannula, and draping was meant not only to prepare her for the procedure but to induce a mild degree of stress such that we could assess the child's coping skills and ability to undergo the procedure. The child performed well throughout the simulated run, and surgery was thus offered. An asleep-awake-asleep technique was planned and employed for surgical removal of the tumour. Cortical and subcortical mapping was used to identify the eloquent tissue. Throughout the procedure, the child was cooperative and anxiety free. Follow-up MRI revealed gross total removal of the lesion. CONCLUSION: A simulated theatre experience allowed us to accurately determine that this young patient, despite relative contraindications, was indeed eligible for awake surgery. We will continue to use this technique for all our young patients in assessing their eligibility for these procedures.