Publications by authors named "Omar Pathmanaban"
The variability in vestibular schwannoma growth rates greatly complicates clinical treatment. Management options are limited to radiological observation, surgery, radiotherapy and, in specific cases, bevacizumab therapy. As such, there is a pressing requirement for growth restricting drugs for vestibular schwannoma.
View Article and Find Full Text PDFBackground: There is currently no consensus on the usefulness of postoperative imaging after ventriculoperitoneal (VP) shunt insertion in adults. The aim of this study was to investigate the utility of routine postoperative imaging (CT head scans and radiographs) following primary VP shunt insertion in a general adult population treated at a tertiary neurosurgical centre.
Methods: Patients undergoing primary VP shunt insertion between 2017-2021 were included.
Article Synopsis
- Craniopharyngiomas are usually benign tumors located in the sellar and suprasellar regions, but rare instances of ectopic tumors can occur, particularly associated with familial adenomatous polyposis (FAP).
- The text discusses a case of an ectopic cerebellopontine angle (CPA) craniopharyngioma in a patient with FAP, marking it as the fifth such documented case.
- This case underlines the importance of considering craniopharyngioma in differential diagnoses for CPA tumors, especially in patients with FAP, suggesting a potential link to genetic mutations.
Skull base chordomas and chondrosarcomas are distinct types of rare, locally aggressive mesenchymal tumors that share key principles of imaging investigation and multidisciplinary care. Maximal safe surgical resection is the treatment choice for each, often via an expanded endoscopic endonasal approach, with or without multilayer skull base repair. Postoperative adjuvant radiation therapy is frequently administered, usually with particle therapy such as proton beam therapy (PBT).
View Article and Find Full Text PDFBackground: Most schwannomas are isolated tumours occurring in otherwise healthy people. However, bilateral vestibular schwannomas (BVS) or multiple non-vestibular schwannomas indicate an underlying genetic predisposition. This is most commonly -related schwannomatosis (SWN), but when BVS are absent, this can also indicate -related or -related SWN.
View Article and Find Full Text PDFBackground: Nonauditory symptoms can be a prominent feature in patients with sporadic vestibular schwannoma (VS), but the cause of these symptoms is unknown. Inflammation is hypothesized to play a key role in the growth and symptomatic presentation of sporadic VS, and in this study, we investigated through translocator protein (TSPO) positron emission tomography (PET) whether inflammation occurred within the "normal appearing" brain of such patients and its association with tumor growth.
Methods: Dynamic PET datasets from 15 patients with sporadic VS (8 static and 7 growing) who had been previously imaged using the TSPO tracer [C]()-PK11195 were included.
Article Synopsis
- New diagnostic criteria for NF2-related schwannomatosis were established in 2022, leading to an updated prevalence study in the UK, which focused on the rate of de novo NF2 cases.
- A total of 1,084 living NF2 patients were identified, indicating a prevalence of 1 in 61,332, with a striking 72% of cases being de novo, many of which were mosaic.
- The findings also revealed that nonsense variants were most common (24.8%), while missense variants had a higher familial association (56%), emphasizing the importance of patient databases for accurate genetic counseling.
Article Synopsis
- Myeloid cells are abundant in glioblastoma (GBM) and exist in various forms with different activation states, but there’s limited understanding of how the tumor microenvironment (TME) affects their behavior.
- Researchers used advanced imaging techniques to analyze and map these myeloid cell populations within the GBM TME, revealing that their distribution is influenced by factors like tissue hypoxia and specific signaling molecules.
- The study found that the organization of these myeloid cells in certain tumor areas corresponds to patient survival rates, providing important insights into how these cells may impact clinical outcomes in GBM patients.
Article Synopsis
- - Meningiomas are the most common primary brain tumors in adults, with an increasing incidence linked to aging and better neuroimaging, and while many are benign, some are aggressive and treatment-resistant, leading to serious health impacts.
- - Recent advancements in understanding meningioma biology have introduced molecular biomarkers for diagnosis and prognosis, but a standardized molecular classification for these tumors is still lacking.
- - A comprehensive consensus review by the International Consortium on Meningiomas aims to guide clinicians and researchers by covering proposed classifications, novel treatment strategies, ongoing studies, and unique management approaches for different patient populations.
Objective: The aim of this study was to describe the natural history of incidental benign-appearing notochordal lesions of the skull base with specific attention to features that can make differentiation from low-grade chordoma more difficult, namely contrast uptake and bone erosion.
Methods: In this retrospective case series, the authors describe the clinical outcomes of 58 patients with incidental benign-appearing notochordal lesions of the clivus, including those with minor radiological features of bone erosion or contrast uptake.
Results: All lesions remained stable during a median follow-up of almost 3 years.
Venous thromboembolism chemical prophylaxis after skull base surgery.
Acta Neurochir (Wien)
April 2024
Purpose: There is no guidance surrounding postoperative venous thromboembolism (VTE) prophylaxis using pharmacological agents (chemoprophylaxis) in patients undergoing skull base surgery. The aim of this study was to compare VTE and intracranial haematoma rates after skull base surgery in patients treated with/without chemoprophylaxis.
Methods: Review of prospective quaternary centre database including adults undergoing first-time skull base surgery (2009-2020).
Evidence on hearing outcome measures when assessing hearing preservation following stereotactic radiosurgery (SRS) for adults with vestibular schwannoma (VS) has not previously been collated in a structured review. The objective of the present study was to perform a scoping review of the evidence regarding the choice of hearing outcomes and other methodological characteristics following SRS for adults with VS. The protocol was registered in the International Platform of Registered Systematic Review and Meta-Analysis Protocols (INPLASY) and reported according to the Preferred Reporting Items for Systematic Review and Meta-Analyses extension guidelines for scoping reviews.
View Article and Find Full Text PDFArticle Synopsis
- Current DCE MRI techniques require full doses of gadolinium-based contrast agents (GBCA), which can be a limitation.
- This study tested a new protocol using a lower GBCA dose in patients with brain tumors to obtain high-resolution kinetic parameters through advanced imaging methods.
- Results indicate that the new low-dose protocol not only offers accurate measurements comparable to full doses but also correlates well with important tissue characteristics like microvessel density.
Objective: Translabyrinthine excision of a vestibular schwannoma is associated with acute vestibular failure. Preoperative intratympanic gentamicin (ITG) injections can improve objective balance function after surgery but its clinical benefits remain to be established.
Methods: Adult patients undergoing translabyrinthine removal of a vestibular schwannoma between January 2014 and February 2018 underwent preoperative vestibular function testing.
Objective: This study aimed to assess degree of audiovestibular handicap in patients with vestibular schwannoma.
Methods: Audiovestibular handicap was assessed using the Hearing Handicap Inventory, Tinnitus Handicap Inventory and Dizziness Handicap Inventory. Patients completed questionnaires at presentation and at least one year following treatment with microsurgery, stereotactic radiosurgery or observation.
Background: The occurrence of hyperostotic bilateral spheno-orbital meningiomas (BSOMs) is very rare. Patients present with bilateral symptoms and require bilateral treatment. This series describes 6 patients presenting to 2 UK neurosurgical units and includes a literature review.
View Article and Find Full Text PDFBilateral vestibular schwannoma is the hallmark of -related schwannomatosis, a rare tumour predisposition syndrome associated with a lifetime of surgical interventions, radiotherapy and off-label use of the anti-angiogenic drug bevacizumab. Unilateral vestibular schwannoma develops sporadically in non--related schwannomatosis patients for which there are no drug treatment options available. Tumour-infiltrating immune cells such as macrophages and T-cells correlate with increased vestibular schwannoma growth, which is suggested to be similar in sporadic and -related schwannomatosis tumours.
View Article and Find Full Text PDFAn operative workflow systematically compartmentalizes operations into hierarchal components of phases, steps, instrument, technique errors, and event errors. Operative workflow provides a foundation for education, training, and understanding of surgical variation. In this Part 1, we present a codified operative workflow for the retrosigmoid approach to vestibular schwannoma resection.
View Article and Find Full Text PDFAn operative workflow systematically compartmentalizes operations into hierarchal components of phases, steps, instrument, technique errors, and event errors. Operative workflow provides a foundation for education, training, and understanding of surgical variation. In this Part 2, we present a codified operative workflow for the translabyrinthine approach to vestibular schwannoma resection.
View Article and Find Full Text PDFBackground: Our neurosurgical unit adopted a model of shared decision-making (SDM) based on multidisciplinary clinics for vestibular schwannoma (VS). A unique feature of this clinic is the interdisciplinary counseling process with a surgeon presenting the option of surgery, an oncologist radiosurgery or radiotherapy, and a specialist nurse advocating for the patient.
Methods: This is a retrospective cohort study.
Article Synopsis
- NF2-schwannomatosis is the leading genetic syndrome linked to meningioma, causing significant health issues due to the presence of multiple tumors like schwannomas and ependymomas.
- Managing meningiomas in NF2-schwannomatosis is complex, requiring careful consideration of treatment options and their risks, focusing on conservative management until patients become symptomatic.
- Effective treatment involves surgery for symptomatic tumors and collaboration with specialized teams, while approaches like radiotherapy and medications (e.g., bevacizumab) have specific roles and limitations in this context.
Article Synopsis
- More people are finding out they have small brain tumors called meningiomas because of advanced imaging technology like MRIs and CT scans.
- Most of these meningiomas don’t grow fast or cause problems, so they might not need treatment.
- Doctors are trying to figure out the best way to manage these tumors since sometimes they can grow and cause issues, but deciding when to treat can be tricky.*
Objective: Skull base meningiomas (SBMs) involving the cavernous sinus encase the internal carotid artery (ICA) and may lead to stenosis of the vessel. Although ischemic stroke has been reported in the literature, there are to the authors' knowledge no reported studies quantifying the risk of stroke in these patients. The authors aimed to determine the frequency of arterial stenosis in patients with SBMs that encase the cavernous ICA and to estimate the risk of ischemic stroke in these patients.
View Article and Find Full Text PDFBackground: Radiation treatment of benign tumors in tumor predisposition syndromes is controversial, but short-term studies from treatment centers suggest safety despite apparent radiation-associated malignancy being reported. We determined whether radiation treatment in NF2-related schwannomatosis patients is associated with increased rates of subsequent malignancy (M)/malignant progression (MP).
Methods: All UK patients with NF2 were eligible if they had a clinical/molecular diagnosis.