Paediatric ventriculoperitoneal shunt failures: 12-year experience from a Singapore children's hospital.

PURPOSE: Cerebrospinal fluid (CSF) shunt failures in children are devastating. The primary aims of this study are to, firstly, review our institutional series of ventriculoperitoneal shunt (VPS) insertions and identify factors associated with shunt failure. METHODS: This is a single-institution, retrospective study conducted over a 12-year period. All patients under 18 years old with VPS inserted were included. Variables of interest such as patient characteristics, hydrocephalus aetiology, shunt implant details, and outcomes were subjected to statistical analyses. RESULTS: A total of 214 VPS patients were selected for this study. The mean age at VPS insertion was 6 months with a mean follow-up duration of 44 months. The most common type of hydrocephalus was obstructive (n = 142, 66.4%), and the most frequent aetiology was tumour-related (n = 66, 30.8%). The 30-day shunt failure rate was 9.3%: 9 infections (4.2%), 7 occlusions (3.3%), and 4 others (1.9%). After multivariable analysis, only recent central nervous system (CNS) infection prior to VPS insertion remained significant (OR 15.4 (1.3-175), p = 0.028). CONCLUSION: This is the first, large-scale local study focused on the shunt failure in Singaporean children. Significant findings in our study demonstrate that recently treated CNS infection is a factor associated with 30-day shunt failure while the values of CSF constituents were not contributory.

Closure intracranial pressure as a determinant of surgical decompression adequacy in spontaneous supratentorial intracerebral haematoma: a multicentre observational study.

PURPOSE: Despite significant advances, the literature on the optimal surgical treatment for spontaneous supratentorial intracerebral haematoma (ICH) remains lacking. Intraoperative ICP measured on closure (closure ICP) was reported to be a potential marker of adequate decompression in various neurosurgical conditions. We hypothesize that closure ICP also correlates with outcomes in ICH. METHODS: A multicentre retrospective study of 203 decompressive surgeries performed for ICHs was conducted (clot evacuation with either craniectomy or craniotomy). Receiver operating characteristic analysis on closure ICP was performed and an optimal threshold of 5 separated the patients into inadequate (iICP; ICP > 5 mmHg) and good decompression (gICP; ICP ≤ 5 mmHg). Postoperative ICP control, modified Rankin scale (mRS) and mortality were reported. RESULTS: There were 85 patients in the iICP and 118 patients in the gICP group respectively. The mean age, median preoperative Glasgow coma scale, ICH laterality, location, and volume were similar. After multivariable analysis, the need for (OR 2.55 [1.31-4.97]) and the duration of postoperative hyperosmolar therapy (iICP: 3 days, gICP: 1 day; p = 0.045), and repeat surgery for refractory ICP (OR 5.80 [1.53-22]) were more likely in the iICP group. The likelihood of mRS improvement at 1-year follow up was significantly worse in the iICP group (OR 0.38 [0.17-0.83], p = 0.015). CONCLUSION: Closure ICP is an objective and reproducible surgical target. When planning for surgical decompression, obtaining closure ICP of ≤ 5 mmHg is potentially able to improve postoperative ICP management and optimise functional recovery in a well selected patient population.

Outcomes of decompressive craniectomy for large territory cerebral infarction with and without prior reperfusion: a multicentre retrospective review.

PURPOSE: Reperfusion therapy has greatly improved outcomes of ischaemic stroke but remains associated with haemorrhagic conversion and early deterioration in a significant proportion of patients. Outcomes in terms of function and mortality are mixed and the evidence for decompressive craniectomies (DC) in this context remains sparse. We aim to investigate the clinical efficacy of DC in this group of patients compared to those without prior reperfusion therapy. METHODS: A multicentre retrospective study was conducted between 2005 and 2020, and all patients with DC for large territory infarctions were included. Outcomes in terms of inpatient and long-term modified Rankin scale (mRS) and mortality were assessed at various time points and compared using both univariable and multivariable analyses. Favourable mRS was defined as 0-3. RESULTS: There were 152 patients included in the final analysis. The cohort had a mean age of 57.5 years and median Charlson comorbidity index of 2. The proportion of preoperative anisocoria was 15.1%, median preoperative Glasgow coma scale was 9, the ratio of left-sided stroke was 40.1%, and ICA infarction was 42.8%. There were 79 patients with prior reperfusion and 73 patients without. After multivariable analysis, the proportion of favourable 6-month mRS (reperfusion, 8.2%; no reperfusion, 5.4%) and 1-year mortality (reperfusion, 26.7%; no reperfusion, 27.3%) were similar in both groups. Subgroup analysis of thrombolysis and/or thrombectomy against no reperfusion was also unremarkable. CONCLUSION: Reperfusion therapy prior to DC performed for large territory cerebral infarctions does not affect the functional outcome and mortality in a well-selected patient population.

Relevance of presenting risks of frailty, sarcopaenia and osteopaenia to outcomes from aneurysmal subarachnoid haemorrhage.

INTRODUCTION: Aneurysmal subarachnoid haemorrhage (aSAH) is a condition with significant morbidity and mortality. Traditional markers of aSAH have established their utility in the prediction of aSAH outcomes while frailty markers have been validated in other surgical specialties. We aimed to compare the predictive value of frailty indices and markers of sarcopaenia and osteopaenia, against the traditional markers for aSAH outcomes. METHODS: An observational study in a tertiary neurosurgical unit on 51 consecutive patients with ruptured aSAH was performed. The best performing marker in predicting the modified Rankin scale (mRS) on discharge was selected and an appropriate threshold for the definition of frail and non-frail was derived. We compared various frailty indices (modified frailty index 11, and 5, and the National Surgical Quality Improvement Program score [NSQIP]) and markers of sarcopaenia and osteopaenia (temporalis [TMT] and zygoma thickness), against traditional markers (age, World Federation of Neurological Surgery and modified Fisher scale [MFS]) for aSAH outcomes. Univariable and multivariable analysis was then performed for various inpatient and long-term outcomes. RESULTS: TMT was the best performing marker in our cohort with an AUC of 0.82, Somers' D statistic of 0.63 and Tau statistic 0.25. Of the frailty scores, the NSQIP performed the best (AUC 0.69), at levels comparable to traditional markers of aSAH, such as MFS (AUC 0.68). The threshold of 5.5 mm in TMT thickness was found to have a specificity of 0.93, sensitivity of 0.51, positive predictive value of 0.95 and negative predictive value of 0.42. After multivariate analysis, patients with TMT ≥ 5.5 mm (defined as non-frail), were less likely to experience delayed cerebral ischaemia (OR 0.11 [0.01 - 0.93], p = 0.042), any complications (OR 0.20 [0.06 - 0.069], p = 0.011), and had a larger proportion of favourable mRS on discharge (95.0% vs. 58.1%, p = 0.024) and at 3-months (95.0% vs. 64.5%, p = 0.048). However, the gap between unfavourable and favourable mRS was insignificant at the comparison of 1-year outcomes. CONCLUSION: TMT, as a marker of sarcopaenia, correlated well with the presenting status, and outcomes of aSAH. Frailty, as defined by NSQIP, performed at levels equivalent to aSAH scores of clinical relevance, suggesting that, in patients presenting with acute brain injury, both non-neurological and neurological factors were complementary in the determination of eventual clinical outcomes. Further validation of these markers, in addition to exploration of other relevant frailty indices, may help to better prognosticate aSAH outcomes and allow for a precision medicine approach to decision making and optimization of best outcomes.

Decompressive surgery in abusive head injury: Experience from a Singapore children's hospital and a review of literature.

PURPOSE: Abusive head trauma (AHT) is a major cause of morbidity and mortality in children. Studies on pediatric head injury observe that AHT patients often have a higher incidence of malignant cerebral oedema and, overall, worse prognosis. There are limited studies with a focus on the outcome of decompressive surgery in children with AHT. This is a study undertaken to review our institutional experience on the role of decompressive surgery in AHT patients and objectively assess its outcomes, in corroboration with current literature. METHODS: This is an ethics-approved, retrospective study. Inclusion criteria consist of all children with a diagnosis of AHT managed by the Neurosurgical Service, KK Women's and Children's Hospital. Demographical and clinical variables are incorporated in the statistical analyses. RESULTS: From 2011 to 2021, a total of 7 patients required decompressive surgery for AHT. Mean age of the cohort was 17.1 months (with the majority of patients being male (n = 5, 71.4%). During the follow-up period, there was 1 mortality (14.3%), 3 patients developed cerebral palsy (42.9%), and 3 patients had post-traumatic epilepsy (42.9%). With regards to functional outcome, 4 patients (57.1%) had a favorable KOSCHI score at 6 months follow-up. CONCLUSION: Decompressive surgery in children with AHT presents with its own unique challenges. We therein present our neurosurgical experience in decompressive surgery for this extremely vulnerable group of patients. Given the potential role of decompressive surgery in AHT, the development of an objective marker to select such patients who may benefit most from intervention should be the way forward.

Prevention and treatment of CSF leaks in congenital complex spinal lipomas.

BACKGROUND: Congenital complex spinal lipomas (CSL) are challenging lesions to treat. Cerebrospinal fluid (CSF) leaks are feared complications due to the risk of infection, and subsequent scarring that may promote retethering. Much has been written in the literature on the surgical technique of CSL resection with less emphasis placed on the prevention and management of CSF leak. METHOD: The authors describe the nuances in the prevention and management of CSF leaks in the context of CSL, including the operative approach, resection, closure and recommended postoperative care. CONCLUSION: CSF leaks are complications that can be minimized with deliberate steps and meticulous surgical technique.

Closure intracranial pressure is an objective intraoperative determinant of the adequacy of surgical decompression in traumatic acute subdural haematoma: a multicentre observational study.

PURPOSE: Acute subdural haematoma (ASDH) is associated with severe traumatic brain injury and poor outcomes. Although guidelines exist for the decompression of ASDH, the question of adequate decompression remains unanswered. The authors examined the relationship of intracranial pressure (ICP) on closure with outcomes to determine its utility in the determination of adequate ASDH decompression. METHODS: A multicentre retrospective review of 105 consecutive patients with ASDH who underwent decompressive surgery was performed. Receiver operating characteristic (ROC) analysis with internal validation was performed to determine an ICP threshold for the division of patients into the inadequate and good ICP groups. Multivariable analyses were performed for both inpatient and long-term outcomes. RESULTS: An ICP threshold of 10 mmHg was identified with a 91.5% specificity, 45.7% sensitivity, and a positive and negative predictive value of 80.8% and 68.4%. There were 26 patients (24.8%) and 79 patients (75.2%) in the inadequate and good ICP groups, respectively. After adjustment, the inadequate ICP group was associated with increased postoperative usage of mannitol (OR 14.2, p < 0.001) and barbiturates (OR 150, p = 0.001). Inadequate ICP was also associated with increased inpatient mortality (OR 24.9, p < 0.001), and a lower rate of favourable MRS at 1 year (OR 0.08, p = 0.008). The complication rate was similar amongst the groups. CONCLUSIONS: Closure ICP is a novel, objective, and actionable intraoperative biomarker that correlates with inpatient and long-term outcomes in ASDH. Various surgical manoeuvres can be undertaken to achieve this target safely. Large-scale prospective studies should be performed to validate this ICP threshold.

Saving the Exposed Deep Brain Stimulation Implant: A Comprehensive Review of Implant Extrusion and Reconstructive Options.

INTRODUCTION: Deep brain stimulation (DBS) for the treatment of Parkinson disease is susceptible to complications, such as hardware extrusion, most commonly at the scalp and chest. The authors describe their experience with the management of hardware extrusion and reconstruction with one of the largest single-institution experience and suggest an evidence-based treatment algorithm for the management of such cases. METHODS: A retrospective review of hospital records was performed to identify patients who underwent DBS-related surgery and reconstruction from January 2015 to April 2020. Management of these patients involved culture-directed antibiotics, local wound debridement, various forms of reconstruction, and hardware removal when indicated. RESULTS: Ninety-four patients with 131 DBS-related procedures were included. Twelve patients (12.8%) had hardware extrusion, of which 6 occurred primarily at the scalp and 6 occurred primarily at the chest. Primary closure of scalp wounds (odds ratio, 0.05 [0.004-0.71], P = 0.035) was negatively associated with treatment success. The type of reconstruction of chest wounds did not affect its success ( P = 0.58); however, none of them involved a new surgical bed, such as contralateral or hypochondrial placement. CONCLUSIONS: Hardware extrusion is a significant complication of DBS-related surgery. Management of extrusion at the scalp should involve the use of tension-free, well-vascularized locoregional flaps as opposed to primary closure. Implantable pulse generator extrusions at the chest can be managed with both primary closure and repositioning in a new surgical bed. Extruded DBS implants may be salvaged with appropriate reconstructive considerations, and the authors suggest an evidence-based treatment algorithm.

Endoscopic excision of an aqueduct of Sylvius cavernoma causing obstructive hydrocephalus: technical note.

BACKGROUND AND IMPORTANCE: Acquired lesions within the aqueduct of Sylvius are rare and their surgical management is challenging. Open transcranial approaches require dissection and manipulation of surrounding eloquent structures. Use of an endoscope can avoid potential morbidity from traversing and handling eloquent structures during open approaches whilst providing better visualisation of an intraventricular lesion. CLINICAL PRESENTATION: A 62-year-old female presented with insidious onset short-term memory loss, unsteady gait, urinary incontinence and left-sided dysaesthesia. Magnetic resonance imaging (MRI) revealed hydrocephalus from an obstructive haemorrhagic lesion consistent with a cavernoma at the central midbrain within the aqueduct of Sylvius. An endoscopic approach was selected to provide optimal visualisation of the lesion. As only a single instrument could be accommodated, rotational movements were employed to tease out the lesion. Gross total resection was achieved. Her symptoms improved immediately postoperatively and she made a complete recovery by 2 months. Post-operative MRI showed resolution of hydrocephalus and no evidence of residual/recurrence of the lesion. Unfortunately, she developed hydrocephalus 3 months post-op and required placement of a ventriculoperitoneal shunt. CONCLUSIONS: Endoscopic resection is safe and feasible for selected periaqueductal lesions as it provides direct access while minimising disruption of the surrounding anatomical structures. The limitation of only having a single instrument can be overcome by employing rotational movements.

Tethered cord secondary to focal nondisjunction of the primary neural tube: experience from a Singapore children's hospital.

PURPOSE: Tethered cord due to focal nondisjunction of primary neuralisation (FNPN) is a rare form of spinal dysraphism. We present our institutional experience in managing children diagnosed with FNPN. MATERIALS AND METHODS: This is a single institution, retrospective study approved by the hospital ethics board. Patients below 18 years of age diagnosed with CDS, LDM or their mixed lesions, and subsequently underwent intervention by the Neurosurgical Service, KK Women's and Children's Hospital, are included. RESULTS: From 2001 to 2021, 16 FNPN patients (50% males) were recruited. Eight of them had CDS (50.0%), seven had LDM (43.8%), and one patient had a mixed CDS and LDM lesion (6.2%). The average duration of follow up was 5.7 years and the mean age of surgery was 6 months old. Thirteen patients underwent prophylactic intent surgery (81.2%) and three had therapeutic intent surgery (18.8%). All patients did not have new neurological deficit or required repeat surgery for cord retethering. We observed that detethering surgery performed at or less than three months old was associated with having a wound infection (p = .022). CONCLUSIONS: Our study reports that early recognition and timely intervention are mainstays of management for FNPN. We advocate a multi-disciplinary approach for good outcomes.

Paediatric Cerebral Arteriovenous Malformation: Outcomes from a Singapore Children's Hospital.

OBJECTIVES: Paediatric brain arteriovenous malformation (bAVM) is a rare and distinct clinical entity. There is a growing body of literature that support the success of multimodality approaches for this difficult condition. The authors aim to firstly, describe our institutional experience with a consecutive series of patients and next, corroborate our results with current literature. MATERIAL AND METHODS: This is a single institution, retrospective study conducted over a 20-year period. Patients less than 19 years old with bAVM were included. Variables of interest included patient demographics, clinical presentation, neuroimaging features, bAVM characteristics and treatment modality. Functional outcomes were measured with modified Rankin scale (mRS). RESULTS: There were 58 paediatric bAVMs, presenting at a mean age of 8.7 ± 4.2 years, and followed up for a mean duration of 7.7 years. Thirty-six patients (62.1%) underwent microsurgical resection, 10 patients had stereotactic radiosurgery (17.2%) and 2 patients had endovascular treatment (3.4%). 50 patients (86.2%) had a favourable outcome at 1-year follow up. Microsurgical resection and SRS had similar obliteration rates (resection 83.3%; SRS 80.0%) and recurrence (resection 10.0%; SRS 12.5%). There were 6 cases of bAVM recurrence (12.8%). This subgroup was noted to be less than 7.5 years old at presentation (OR 15.0, 95% CI 1.56 - 144), and less likely to present with bAVM rupture (OR 0.11, 95% CI 0.01 - 0.96). CONCLUSION: This study describes our experience in managing paediatric bAVM, whereby monomodal therapy can still be effective. Of note, we also demonstrate the role of extended surveillance to detect recurrence.

Decompressive craniectomy for internal carotid artery and middle carotid artery infarctions: a long-term comparative outcome study.

OBJECTIVE: Malignant internal carotid artery (ICA) infarction is an entirely different disease entity when compared with middle cerebral artery (MCA) infarction. Because of an increased area of infarction, it is assumed to have a poorer prognosis; however, this has never been adequately investigated. Decompressive craniectomy (DC) for malignant MCA infarction has been shown to improve mortality rates in several randomized controlled trials. Conversely, aggressive surgical decompression for ICA infarction has not been recommended. The authors sought to compare the functional outcomes and survival between patients with ICA infarctions and those with MCA infarctions after DC in the largest series to date to investigate this assumption. METHODS: A multicenter retrospective review of 154 consecutive DCs for large territory cerebral infarctions performed from 2005 to 2020 were analyzed. Patients were divided into ICA and MCA groups depending on the territory of infarction. Variables, including age, sex, medical comorbidities, laterality of the infarction, preoperative neurological status, primary stroke treatment, and the time from stroke onset to DC, were recorded. Univariable and multivariable analyses were performed for the clinical exposures for functional outcomes (modified Rankin Scale [mRS] score) on discharge and at the 1- and 6-month follow-ups, and for mortality, both inpatient and at the 1-year follow-up. A favorable mRS score was defined as 0-2. RESULTS: There were 67 patients (43.5%) and 87 patients (56.5%) in the ICA and MCA groups, respectively. Univariable analysis showed that the ICA group had a comparably favorable mRS (OR 0.15 [95% CI 0.18-1.21], p = 0.077). Inpatient mortality (OR 1.79 [95% CI 0.79-4.03], p = 0.16) and 1-year mortality (OR 2.07 [95% CI 0.98-4.37], p = 0.054) were comparable between the groups. After adjustment, a favorable mRS score at 6 months (OR 0.17 [95% CI 0.018-1.59], p = 0.12), inpatient mortality (OR 1.02 [95% CI 0.29-3.57], p = 0.97), and 1-year mortality (OR 0.94 [95% CI 0.41-2.69], p = 0.88) were similar in both groups. The overall survival, plotted using the Cox proportional hazard regression, did not show a significant difference between the ICA and MCA groups (HR 0.581). CONCLUSIONS: Unlike previous smaller studies, this study found that patients with malignant ICA infarction had a functional outcome and survival that was similar to those with MCA infarction after DC. Therefore, DC can be offered for malignant ICA infarction for life-saving purposes with limited functional recovery.

COVID-19 response measures - a Singapore Neurosurgical Academic Medical Centre experience segregated team model to maintain tertiary level neurosurgical care during the COVID-19 outbreak.

AIM: This article aims to inform and share the experience of a Singaporean tertiary level neurosurgical unit in an academic medical centre during the COVID-19 outbreak. METHOD: This is a descriptive study of our segregation team model which is designed with the aim of optimizing manpower and ensuring the safety and welfare of the neurosurgical unit, while maintaining and prioritizing excellent patient care. RESULT: We describe our method of team segregation, rostering, and outline some principles that we adhere to in its design. We also summarise the restructuring of our inpatient and outpatient service, including the operating theatre and protocols for specific procedures, intensive care and general wards, as well as clinic services and multidisciplinary meetings. CONCLUSION: We end with a commentary on residency training and anticipated challenges. Given the likely protracted course of the pandemic, it is key to account for sustainability of such measures and the conservation of resource via the reduction of pateint volume, upkeep of staff emotional and physical health and harnessing technologies such as telemedicine.

Use of fluorescein sodium to obtain histological diagnosis of primary Central nervous system lymphoma ghost tumour despite disappearance on intraoperative magnetic resonance imaging: technical note and review of the literature.

BACKGROUND AND IMPORTANCE: Corticosteroid pre-treatment in patients with primary central nervous system lymphoma (PCNSL) can lead to the phenomenon of ghost tumours (GhT). This affects the diagnostic yield of biopsies and potentially causes misdiagnosis of the condition. The usual strategy of neuronavigation using preoperative magnetic resonance imaging (MRI) or localisation using intraoperative MRI (iMRI) can be rendered ineffective in this situation. CLINICAL PRESENTATION: A middle-aged Chinese male with newly diagnosed human immunodeficiency virus infection was found to have an intracranial lesion suggestive of PCNSL. Preoperatively corticosteroid led to an attenuation of the contrast enhancing lesion on iMRI. However, intraoperative use of FS allowed the successful identification, biopsy and diagnosis of the condition. CONCLUSION: FS is useful in the biopsy of PCNSL GhT even when the lesion is not seen in subsequent MRI imaging.

External Validation of Hematoma Expansion Scores in Spontaneous Intracerebral Hemorrhage in an Asian Patient Cohort.

BACKGROUND: Hematoma expansion (HE) occurs in approximately one-third of patients with intracerebral hemorrhage (ICH) and is known to be a strong predictor of neurological deterioration as well as poor functional outcome. This study aims to externally validate three risk prediction models of HE (PREDICT, 9-point, and BRAIN scores) in an Asian population. METHODS: A prospective cohort of 123 spontaneous ICH patients admitted to a tertiary hospital (certified stroke center) in Singapore was recruited. Logistic recalibrations were performed to obtain updated calibration slopes and intercepts for all models. The discrimination (c-statistic), calibration (Hosmer-Lemeshow test, le Cessie-van Houwelingen-Copas-Hosmer test, Akaike information criterion), overall performance (Brier score, R2), and clinical usefulness (decision curve analysis) of the risk prediction models were examined. RESULTS: Overall, the recalibrated PREDICT performed best among the three models in our study cohort based on the novel matrix comprising of Akaike information criterion and c-statistic. The PREDICT model had the highest R2 (0.26) and lowest Brier score (0.14). Decision curve analyses showed that recalibrated PREDICT was more clinically useful than 9-point and BRAIN models over the greatest range of threshold probabilities. The two scores (PREDICT and 9-point) which incorporated computed tomography (CT) angiography spot sign outperformed the one without (BRAIN). CONCLUSIONS: To our knowledge, this is the first study to validate HE scores, namely PREDICT, 9-Point and BRAIN, in a multi-ethnic Asian ICH patient population. The PREDICT score was the best performing model in our study cohort, based on the performance metrics employed in this study. Our findings also showed support for CT angiography spot sign as a predictor of outcome after ICH. Although the models assessed are sufficient for risk stratification, the discrimination and calibration are at best moderate and could be improved.

Traumatic cavernous sinus syndrome - A peculiar presentation of multiple cranial nerve neuropathies following a minor head injury: Case report and literature review.

BACKGROUND: In patients with traumatic head injuries, the percentage of cranial nerve injuries (CNI) range from4.3 to 17.6% in which majority are isolated CNI[1-5].In present literature, moderate to severe types of head injuries are often studied which may result in a lack of representation and description of CNI associated with minor head injuries (MHI). Alongside this peculiar case of a traumatic cavernous sinus syndrome (CSS) that is non-thrombotic and non-fistulous in nature, this paper aims to analyse traumatic CNI in non-severe head injuries and the surrounding literature. CASE REPORT: A 65-year-old man who had sustained a minor head injury was found to have CNI of III, IV and VI.Brain imaging showed scattered traumatic subarachnoid haemorrhage and a non-displaced right zygomatic arch fracture. Despite the short course of high dose dexamethasone, he showed only partial recovery of his CNI after one year. CONCLUSION: We present a case of traumatic CSS likely secondary to tractional injury from a MHI. Injury to the extraocular nerves wasfound to be one of the more commonly observed combination of CNI from the literature review conducted. In patients with MHI, multiple CNI is less common. Hence, consideration should be given to work upfor secondary causes such as tumours. There is presently no known clear identifiable pattern of CNI associated with MHI. CT brain findings of skull base fractures and early onset of cranial nerve palsies are generally associated with worse outcomes. More remains to be studied about tractional CNI in non-severe head injuries.

Selective dorsal rhizotomy using a 3D high definition exoscope.

Selective dorsal rhizotomy (SDR) is an established neurosurgical technique for children with spastic diplegia secondary to cerebral palsy. Meticulous intraoperative testing of individual nerve roots with electromyography in tandem with the on-site neurorehabilitation team is recommended for good clinical outcomes. The standard approach requires the neurosurgeons to spend extended time under the traditional operating microscope. In this video, the authors describe the use of a 3D exoscope system for SDR. Overall, the 3D exoscope improves ergonomics and reduces musculoskeletal fatigue for the operating neurosurgeons. Furthermore, it provides excellent visualization of important structures, allowing safe and efficient completion of the procedure. The video can be found here: https://stream.cadmore.media/r10.3171/2023.10.FOCVID23105.

Complex lumbosacral spinal cord lipomas: A longitudinal study on outcomes from a Singapore children's hospital.

BACKGROUND: Total/near-total resection (TR/NTR) of complex lumbosacral lipomas (CSL) is reported to be associated with better long-term functional outcomes and lower symptomatic re-tethering rates. We report our institutional experience for CSL resection in affected children. METHODS: This is a single-institution, retrospective study. Inclusion criteria consist of patients with CSL with dorsal, transitional and chaotic lipomas based on Pang et al's classification. The study population is divided into 2 groups: asymptomatic patients with a normal preoperative workup referred to as 'prophylactic intent' and 'therapeutic intent' for those with pre-existing neuro-urological symptoms. Primary aims are to review factors that affect post-operative clean intermittent catheterization (CIC), functional outcomes based on Necker functional score (NFS), and re-tethering rates. RESULTS: 122 patients were included from 2000 to 2021. There were 32 dorsal lipomas (26.2 %), 74 transitional lipomas (60.7 %), and 16 chaotic lipomas (13.1 %). 82 % patients achieved TR/NTR. Favourable NFS at 1-year was 48.2 %. The re-tethering rate was 6.6 %. After multivariable analysis, post-operative CIC was associated with median age at surgery (p = 0.026), lipoma type (p = 0.029), conus height (p = 0.048) and prophylactic intent (p < 0.001). Next, extent of lipoma resection (p = 0.012) and the post-operative CSF leak (p = 0.004) were associated with re-tethering. Favourable NFS was associated with lipoma type (p = 0.047) and prophylactic intent surgery (p < 0.001). CONCLUSIONS: Our experience shows that TR/NTR for CSL is a feasible option to prevent functional deterioration and re-tethering. Efforts are needed to work on factors associated with post-operative CIC.

Fibrofatty filum terminale: long-term outcomes from a Singapore children's hospital.

OBJECTIVE: The role of prophylactic detethering a fibrofatty filum terminale (FFT) remains equivocal. Furthermore, long-term studies focusing on urological outcomes are sparse. The aims of this study were to present an institutional experience on the perioperative and long-term outcomes of FFT surgery and to assess for factors that contribute to postoperative clean intermittent catheterization (CIC). METHODS: This was a single-institution, retrospective study conducted over a 20-year period. Patients younger than 19 years of age who underwent surgery for FFT were included. Variables of interest included patient demographics, clinical presentation, radiological findings, postoperative complications, and long-term need for CIC. Outcomes were measured using the Necker functional score and modified Hoffer Functional Ambulation scale score at 3, 6, and 12 months postdischarge. RESULTS: A total of 164 surgeries were performed for FFT from 2000 to 2020. The median age at surgery was 1.1 years, and the mean follow-up duration was 8.3 years. There were 115 patients (70.1%) who underwent prophylactic-intent surgery and 49 patients (29.9%) who underwent therapeutic-intent surgery. The proportion of therapeutic-intent surgeries increased significantly with age percentiles (0-20th, 21.9%; 20th-40th, 9.1%; 40th-60th, 18.2%; 60th-80th, 36.4%; and 80th-100th, 63.6% [p < 0.001]). Thirty patients (18.3%) had an associated syndrome, the most common (n = 19, 11.6%) being VACTERL (vertebral defects, anal atresia, cardiac defects, tracheo-esophageal fistula, renal anomalies, and limb abnormalities). Forty-eight patients (29.3%) had an associated malformation (anorectal anomaly = 37, urogenital anomaly = 16, and sacral anomaly = 3). Cutaneous manifestation was the most common presentation (n = 96, 58.5%), followed by lower-limb neurological deficits (n = 21, 12.8%). A low-lying conus was present in 36.0% of patients (n = 59), and 16.5% had an associated syrinx (n = 27). There were 26 patients (18.8%) with an abnormal preoperative urodynamic study. Three patients (1.8%) had postoperative complications that required repeat surgery. There were no cases of CSF leakage. One patient (0.6%) developed retethering requiring another surgery. Postoperative CIC was required in 11 patients (6.7%). Multivariable analyses showed that an abnormal preoperative urodynamic study (adjusted OR 5.5 [95% CI 1.27-23.9], p = 0.023) and having an intraspinal syrinx (adjusted OR 5.29 [95% CI 1.06-26.4], p = 0.042) were associated with the need for CIC. CONCLUSIONS: The authors' results demonstrate that detethering surgery for FFT is a relatively safe procedure and can be performed prophylactically. Nonetheless, the risks of postoperative CIC should be emphasized during the preoperative counseling process.

The pressure differential efflux technique - A novel approach for troubleshooting air-locked external ventricular drainage systems: A technical note and review of literature.

External ventricular drainage (EVD) is carried out in many neurosurgical conditions for the diversion of cerebrospinal fluid. These EVD systems can, however, malfunction with potentially lethal consequences. Air bubbles within the EVD can result in air locking of the system with subsequent blockage of drainage, with blood clots and debris being the other causes. There are both non-invasive and invasive methods of rectifying such blockages, with invasive procedures having its associated risks. This is especially so for EVD revisions, with each surgery increasing the risk of ventriculitis. We describe a case of bilateral air locked EVD managed successfully with a novel non-invasive 'pressure differential efflux technique'. This method exploits the pressure gradient established by adjusting each EVD to a different height to evacuate the pneumoventricle. In addition, we present a sequential approach to the management of EVD malfunction, based on the current literature and our institutional protocol.