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Anatomical Record (Hoboken, N.J. : 2007) Jun 2024The existence of a previously unrecognized subarachnoid lymphatic-like membrane (SLYM) was reported in a recent study. SLYM is described as an intermediate... (Review)
Review
The existence of a previously unrecognized subarachnoid lymphatic-like membrane (SLYM) was reported in a recent study. SLYM is described as an intermediate leptomeningeal layer between the arachnoid and pia mater in mouse and human brains, which divides the subarachnoid space (SAS) into two functional compartments. Being a macroscopic structure, having missed detection in previous studies is surprising. We systematically reviewed the published reports in animals and humans to explore whether prior descriptions of this meningeal layer were reported in some way. A comprehensive search was conducted in PubMed/Medline, EMBASE, Google Scholar, Science Direct, and Web of Science databases using combinations of MeSH terms and keywords with Boolean operators from inception until 31 December 2023. We found at least eight studies that provided structural evidence of an intermediate leptomeningeal layer in the brain or spinal cord. However, unequivocal descriptions for this layer all along the central nervous system were scarce. Obscure names like the epipial, intermediate meningeal, outer pial layers, or intermediate lamella were used to describe it. Its microscopic/ultrastructural details closely resemble the recently reported SLYM. We further examined the counterarguments in current literature that are skeptical of the existence of this layer. The potential physiological and clinical implications of this new meningeal layer are significant, underscoring the urgent need for further exploration of its structural and functional details.
PubMed: 38924700
DOI: 10.1002/ar.25524 -
Frontiers in Endocrinology 2024Acromegaly is a rare endocrine disorder caused by hypersecretion of growth hormone (GH) from a pituitary adenoma. Elevated GH levels stimulate excess production of...
UNLABELLED
Acromegaly is a rare endocrine disorder caused by hypersecretion of growth hormone (GH) from a pituitary adenoma. Elevated GH levels stimulate excess production of insulin-like growth factor 1 (IGF-1) which leads to the insidious onset of clinical manifestations. The most common primary central nervous system (CNS) tumors, meningiomas originate from the arachnoid layer of the meninges and are typically benign and slow-growing. Meningiomas are over twice as common in women as in men, with age-adjusted incidence (per 100,000 individuals) of 10.66 and 4.75, respectively. Several reports describe co-occurrence of meningiomas and acromegaly. We aimed to determine whether patients with acromegaly are at elevated risk for meningioma. Investigation of the literature showed that co-occurrence of a pituitary adenoma and a meningioma is a rare phenomenon, and the majority of cases involve GH-secreting adenomas. To the best of our knowledge, a systematic review examining the association between meningiomas and elevated GH levels (due to GH-secreting adenomas in acromegaly or exposure to exogenous GH) has never been conducted. The nature of the observed coexistence between acromegaly and meningioma -whether it reflects causation or mere co-association -is unclear, as is the pathophysiologic etiology.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/prospero/, identifier CRD42022376998.
Topics: Humans; Meningioma; Acromegaly; Meningeal Neoplasms; Human Growth Hormone; Risk Factors; Adenoma
PubMed: 38919490
DOI: 10.3389/fendo.2024.1407615 -
Neurosurgical Review Jun 2024Aim of the present study was to conduct a comprehensive review of surgical strategies that can be offered to patients with trigeminal neuralgia undergoing microvascular... (Review)
Review
A systematic review on the efficacy of adjunctive surgical strategies during microvascular decompression for trigeminal neuralgia without intraoperative evidence of neurovascular conflict.
Aim of the present study was to conduct a comprehensive review of surgical strategies that can be offered to patients with trigeminal neuralgia undergoing microvascular decompression (MVD) surgery and without intraoperative evidence of neurovascular conflict, with a high pre-operative suspicion of conflict lacking intraoperative confirmation, or individuals experiencing recurrence after previous treatment. This systematic review followed established guidelines (PRISMA) to identify and critically appraise relevant studies. The review question was formulated according to the PICO (P: patients; I: intervention; C: comparison; O: outcomes) framework as follows. For patients with trigeminal neuralgia (P) undergoing MVD surgery (I) without demonstrable preoperative neurovascular conflict, high suspicion of conflict but no intraoperative confirmation or recurrence after previous treatment (C), do additional surgical techniques (nerve combing, neurapraxia, arachnoid lysis) (O) improve pain relief outcomes (O)? The search of the literature yielded a total of 221 results. Duplicate records were then removed (n = [76]). A total of 143 papers was screened, and 117 records were excluded via title and abstract screening; 26 studies were found to be relevant to our research question and were assessed for eligibility. Upon full-text review, 17 articles were included in the review, describing the following techniques; (1) internal neurolysis (n = 6) (2) arachnoid lysis/adhesiolysis (n = 2) (3) neurapraxia (n = 3) (4) partial rhizotomy of the sensory root (n = 4) (5) pontine descending tractotomy (n = 2). The risk of bias was assessed using the ROBINS-I (Risk of Bias in Non-randomized Studies - of Interventions) assessment tool. While the described techniques hold promise, further research is warranted to establish standardized protocols, refine surgical approaches, and comprehensively evaluate long-term outcomes.
Topics: Trigeminal Neuralgia; Humans; Microvascular Decompression Surgery; Treatment Outcome
PubMed: 38884812
DOI: 10.1007/s10143-024-02498-7 -
Clinical Neurology and Neurosurgery Jul 2024The Liliequist membrane (LM) represents a crucial yet challenging anatomical structure in neuroanatomy. First observed in 1875 and later elucidated by Bengt Liliequist... (Review)
Review
BACKGROUND
The Liliequist membrane (LM) represents a crucial yet challenging anatomical structure in neuroanatomy. First observed in 1875 and later elucidated by Bengt Liliequist in 1956, the LM's precise anatomical description and boundaries remain complex. Its significance extends to neurosurgery, impacting various procedures like endoscopic third ventriculocisternostomies, aneurysm and tumor surgeries, treatment of suprasellar arachnoid cysts, and managing perimesencephalic hemorrhages. However, a comprehensive understanding of the LM is hindered by inconsistent anatomical descriptions and limitations in available literature, warranting a systematic review.
METHODS
A systematic review was conducted by searching PubMed, Science Direct, and Google Scholar for articles pertaining to Liliequist's membrane. The search employed Mesh terms like "Liliequist membrane," "Liliequist's diaphragm," and related variations. Inclusion criteria encompassed studies exploring the historical evolution, anatomical structure, radiological characteristics, and clinical implications of the LM in neurosurgery.
RESULTS
The search yielded 358 articles, with 276 unique articles screened based on relevance. Following a meticulous screening process, 72 articles underwent full-text assessment, resulting in the inclusion of 5 articles meeting the eligibility criteria. The selected studies varied in methodology, including anatomical dissections, radiological evaluations, and clinical significance in neurosurgical procedures. Insights were derived on LM's anatomical variations, radiological visualization, and its critical role in guiding neurosurgical interventions.
CONCLUSIONS
Despite advancements in understanding its clinical significance and radiological visualization, challenges persist in precisely delineating its boundaries. Further research, especially on embryological development and histological characterization, is essential. Enhancing comprehension of LM-related pathologies is crucial for accurate preoperative planning and optimizing patient outcomes in neurosurgery.
Topics: Humans; Neurosurgical Procedures; History, 20th Century; History, 19th Century; Clinical Relevance
PubMed: 38795689
DOI: 10.1016/j.clineuro.2024.108322 -
Clinical Neurology and Neurosurgery May 2024Extraparenchymal localization of neurocysticercosis (NCC) is rare in non-endemic areas. A case of mixed (intraventricular, IV, and subarachnoid basal, SAB) NCC was... (Review)
Review
OBJECTIVE
Extraparenchymal localization of neurocysticercosis (NCC) is rare in non-endemic areas. A case of mixed (intraventricular, IV, and subarachnoid basal, SAB) NCC was surgically treated using the neuroendoscope and a systematic review of the literature was performed with the aim to analyze the use of this instrument in the management of the extraparenchymal forms of the parasitic disease.
MATERIALS AND METHODS
Medline and Embase databases were searched for studies where the neuroendoscope was used for the management of IV/SAB NCC cysts, either for the cerebrospinal fluid diversion or cyst removal. Cyst location, complete removal, cyst breakage during removal, intraoperative and postoperative complications, administration of antihelmintic therapy, outcome and follow-up period were extracted from the articles.
RESULTS
281 patients were treated by means of the neuroendoscope. 254 patients who were described in retrospective cohort studies, came all from endemic areas, with no significant difference between sexes. Mean age at surgery was 30.7 years. Of all cysts reported in retrospective studies, 37.9% were located in the fourth ventricle. An attempt of cyst removal was described in the 84.6% of cases and an endoscopic third ventriculostomy was performed in another 76.4%. A small number of complications were reported intraoperatively (9.1%) obtaining, but a good recovery was achieved at follow-up. Only 17 ventriculoperitoneal shunts were placed after the first procedure, defining a low risk of postoperative hydrocephalus even in case of partial cyst removal.
CONCLUSION
Neuroendoscopic removal of an extraparenchymal NCC cyst is a safe procedure that should be preferred for lateral and third ventricle localization and, in a specialized centre, even for a localization in the fourth ventricle if feasible. It is also efficient because of the possibility of performing an internal CSF diversion concomitantly to cyst removal, avoiding the complication registered with VPS. The need for cysticidal treatment after surgery should be addressed in a prospective study.
Topics: Humans; Neurocysticercosis; Neuroendoscopy; Adult; Subarachnoid Space; Male; Female; Fourth Ventricle; Ventriculostomy
PubMed: 38569248
DOI: 10.1016/j.clineuro.2024.108268 -
Acta Neurochirurgica Mar 2024The management of craniopharyngiomas is challenging due to their high rate of recurrence following resection. Excision of recurrent tumors poses further surgical...
BACKGROUND
The management of craniopharyngiomas is challenging due to their high rate of recurrence following resection. Excision of recurrent tumors poses further surgical challenges due to loss of arachnoidal planes and adherence to anatomical structures. The endoscopic endonasal approach (EEA) offers a favorable alternative to transcranial approaches for primary craniopharyngiomas. However, the safety and efficacy of EEA for recurrent tumors, specifically after a prior transcranial approach, needs further investigation.
METHODS
We performed a systematic review using PubMed to develop a database of cases of recurrent craniopharyngiomas previously treated with a transcranial approach.
RESULTS
Fifteen articles were included in this review with a total of 75 cases. There were 50 males and 25 females with a mean age of 38 years (range 2-80). One prior transcranial surgery was done in 80.0% of cases, while 8.0% had two and 12.0% had more than two prior surgeries. Radiotherapy after transcranial resection was given in 18 cases (24.0%). Following EEA, vision improved in 60.0% of cases, and vision worsened in 8.6% of the cases. Of cases, 64.4% had pre-existing anterior hypopituitarism, and 43.8% had diabetes insipidus prior to EEA. New anterior hypopituitarism and diabetes insipidus developed in 24.6% and 21.9% of cases, respectively following EEA. Gross total resection (GTR) was achieved in 64.0%, subtotal resection in 32.0%, and partial resection in 4.0% revision EEA cases. GTR rate was higher in cases with no prior radiotherapy compared to cases with prior radiotherapy (72.0% vs 39.0%, p = 0.0372). The recurrence rate was 17.5% overall but was significantly lower at 10.0% following GTR (p = 0.0019). The average follow-up length was 41.2 months (range, 1-182 months).
CONCLUSION
The EEA can be utilized for resection of recurrent or residual craniopharyngiomas previously managed by a transcranial approach.
Topics: Humans; Craniopharyngioma; Diabetes Insipidus; Endoscopy; Hypopituitarism; Pituitary Neoplasms
PubMed: 38430312
DOI: 10.1007/s00701-024-05980-9 -
World Neurosurgery Mar 2024Cerebral vasospasm in patients after aneurysmal subarachnoid hemorrhage (aSAH) continues to be a major source of morbidity despite significant clinical and basic science... (Meta-Analysis)
Meta-Analysis Review
INTRODUCTION
Cerebral vasospasm in patients after aneurysmal subarachnoid hemorrhage (aSAH) continues to be a major source of morbidity despite significant clinical and basic science research. The removal of blood and its degradation products from the subarachnoid space through prophylactic lumbar drainage (LD) is a favorable option. However, several studies have delivered conflicting conclusions on its efficacy after aSAH.
METHODS
Systematic searches of Medline, Embase, and Cochrane Central Register of Controlled Trials were performed. The primary outcome was a good functional outcome (modified Rankin scale score, 0-2). Secondary outcomes included symptomatic vasospasm, secondary cerebral infarction, and mortality.
RESULTS
A total of 14 studies reporting on 2473 patients with aSAH were included in the meta-analysis. Compared with the non-LD group, no significant differences were found in the rates of good functional outcomes in the LD group at discharge to 1 month (risk ratio [RR], 1.28; 95% confidence interval [CI], 0.64-2.58) or at 6 months (RR, 1.12; 95% CI, 0.97-1.41). These findings were consistent in the subgroup analyses of only randomized controlled trials or observational studies. LD was associated with lower rates of symptomatic vasospasm (RR, 0.61; 95% CI, 0.48-0.77), secondary cerebral infarction (RR, 0.59; 95% CI, 0.45-0.79), and mortality at discharge to 1 month (RR, 0.58; 95% CI, 0.41-0.82). The effect on mortality diminished at 6 months (RR, 0.70; 95% CI, 0.34-1.45). However, when analyzing only randomized controlled trials, the benefit of LD on lower rates of mortality continued even at 6 months (RR, 0.75; 95% CI, 0.58-0.99).
CONCLUSIONS
For aSAH patients, the use of LD is associated with benefits in the rates of vasospasm, secondary cerebral infarctions, and mortality, without an increased risk of adverse events.
Topics: Humans; Autonomic Nervous System Diseases; Cerebral Infarction; Cerebrospinal Fluid Leak; Drainage; Subarachnoid Hemorrhage; Subarachnoid Space; Treatment Outcome; Vasospasm, Intracranial
PubMed: 38246528
DOI: 10.1016/j.wneu.2024.01.062 -
Surgical Neurology International 2023Chronic subdural hematoma (CSDH) is a condition characterized by the accumulation of fluid, blood, and blood breakdown products between the brain's arachnoid and dura...
BACKGROUND
Chronic subdural hematoma (CSDH) is a condition characterized by the accumulation of fluid, blood, and blood breakdown products between the brain's arachnoid and dura mater coverings. While steroids have been explored as a potential treatment option, their efficacy and safety remain uncertain. This meta-analysis and systematic review aimed to assess the impact of steroids on CSDH management, including mortality, recurrence, complications, and functional outcomes.
METHODS
We conducted a comprehensive literature search in major electronic databases up to June 2023, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and Cochrane Handbook for Systematic Reviews and Interventions. Inclusion criteria encompassed adult patients with CSDH, the use of steroids as monotherapy or adjuvant therapy, and clearly defined outcomes. Randomized controlled trials and cohort studies meeting these criteria were included in the study.
RESULTS
The initial search yielded 4315 articles, with 12 studies meeting the inclusion criteria. Our findings indicate a non-significant trend toward reduced mortality with steroids in combination with standard care (Odds ratios [OR] = 0.66, 95% confidence interval [CI] 0.20-2.18). However, substantial heterogeneity was observed (I = 70%). Sensitivity analysis, excluding influential studies, suggested a potential increased mortality risk associated with steroids (OR = 1.47, 95% CI 0.87-2.48). Steroids showed a possible benefit in reducing the recurrence of CSDH (OR = 0.58, 95% CI 0.20-1.67), but with significant heterogeneity (I = 89%). No clear advantage of steroids was observed in terms of functional outcomes at three months (modified Rankin scale scores). Furthermore, steroids were associated with a significantly higher incidence of adverse effects and complications (OR = 2.17, 95% CI 1.48-3.17).
CONCLUSION
Steroids may have a potential role in reducing CSDH recurrence but do not appear to confer significant advantages in terms of mortality or functional outcomes. However, their use is associated with a higher risk of adverse effects and complications. Given the limitations of existing studies, further research is needed to refine the role of steroids in CSDH management, considering patient-specific factors and treatment protocols.
PubMed: 38213424
DOI: 10.25259/SNI_771_2023 -
World Neurosurgery Feb 2024The role of surgical management of arachnoid cyst (AC) of the cerebellopontine angle (CPA) is uncertain. This topic has remained controversial with varying contradictory...
OBJECTIVE
The role of surgical management of arachnoid cyst (AC) of the cerebellopontine angle (CPA) is uncertain. This topic has remained controversial with varying contradictory recommendations in the literature, which is limited to mostly case reports. We aimed to provide a comprehensive summary and analysis of symptoms, operative techniques, outcomes, and recurrence of all available surgical cases of AC of the CPA to date.
METHODS
A systematic literature search was performed in May 2022 querying several scientific databases. Inclusion criteria specified all studies and case reports of patients with AC located at the CPA for which any relevant surgical procedures were performed.
RESULTS
A total of 55 patients from the literature and 5 treated at our institution were included. Mean patient age was 29 years (range, 0.08-79 years), with nearly twice (1.7×) as many female as male patients (37 female, 22 male). Headaches (35%), hearing loss (30%), vertigo (22%), and ataxia (22%) were the most common presentations. Following surgery, 95% experienced symptom improvement, with complete resolution in 64%. Of patients with hearing loss, 44% reported a return to normal. The rate of mortality was 1.69%, and 10% of tumors recurred (mean follow-up 2.3 years [range, 0-15 years].
CONCLUSIONS
Symptomatic AC of the CPA is rare. It exhibits a proclivity for females and commonly manifests with headache, hearing loss, vertigo, and ataxia. While careful selection for surgical candidacy is needed and intervention should be reserved for patients with severe symptoms, surgical decompression is an effective tool for symptom alleviation and recovery.
Topics: Humans; Male; Female; Infant, Newborn; Infant; Child, Preschool; Child; Adolescent; Young Adult; Adult; Middle Aged; Aged; Cerebellopontine Angle; Hearing Loss; Headache; Vertigo; Deafness; Arachnoid Cysts; Ataxia
PubMed: 38070740
DOI: 10.1016/j.wneu.2023.12.018 -
Neurosurgical Review Sep 2023Endoscopic transsphenoidal surgery is a novel surgical technique requiring specific training. Different models and simulators have been recently suggested for it, but no... (Review)
Review
Endoscopic transsphenoidal surgery is a novel surgical technique requiring specific training. Different models and simulators have been recently suggested for it, but no systematic review is available. To provide a systematic and critical literature review and up-to-date description of the training models or simulators dedicated to endoscopic transsphenoidal surgery. A search was performed on PubMed and Scopus databases for articles published until February 2023; Google was also searched to document commercially available. For each model, the following features were recorded: training performed, tumor/arachnoid reproduction, assessment and validation, and cost. Of the 1199 retrieved articles, 101 were included in the final analysis. The described models can be subdivided into 5 major categories: (1) enhanced cadaveric heads; (2) animal models; (3) training artificial solutions, with increasing complexity (from "box-trainers" to multi-material, ct-based models); (4) training simulators, based on virtual or augmented reality; (5) Pre-operative planning models and simulators. Each available training model has specific advantages and limitations. Costs are high for cadaver-based solutions and vary significantly for the other solutions. Cheaper solutions seem useful only for the first stages of training. Most models do not provide a simulation of the sellar tumor, and a realistic simulation of the suprasellar arachnoid. Most artificial models do not provide a realistic and cost-efficient simulation of the most delicate and relatively common phase of surgery, i.e., tumor removal with arachnoid preservation; current research should optimize this to train future neurosurgical generations efficiently and safely.
Topics: Humans; Animals; Endoscopy; Cadaver; Computer Simulation; Databases, Factual; Skull Base Neoplasms
PubMed: 37725193
DOI: 10.1007/s10143-023-02149-3