Understanding metastatic involvement of the conus medullaris: a systematic review of clinical presentations, diagnostic approaches, treatment options, and patient outcomes.

INTRODUCTION: Metastasis to the conus medullaris (CM) is a rare but devastating condition. This systematic review aimed to evaluate the clinical presentation, diagnostic workup, treatment options, and outcomes of patients with CM metastasis. By synthesizing the available evidence, this study seeks to improve our understanding of this condition and inform clinical practice. MATERIALS AND METHODS: A systematic review adhering to PRISMA guidelines analyzed literature on CM metastasis from 1997 to January 2024. Human studies in English were included, focusing on primary research articles. Screening criteria ensured a homogeneous study population, with data analyzed using SPSS 26 and assessed for quality using the JBI checklist. RESULTS: The study analyzed 88 patients with conus medullaris metastasis. Common symptoms included back pain (49.3%), sensory impairment (75%), and bladder dysfunction (60.3%). MRI was the primary diagnostic tool, revealing lesions above L1 (37%) or between L1 and L2 (29%). Treatment involved surgery with laminectomy, and combined therapy (surgery plus radiotherapy) in 81.3%. Postoperative outcomes showed improved motor function in 59.6% of patients, while combined therapy yielded better sensory and bowel/bladder function recovery. Median survival was 100 days. CONCLUSION: Metastasis to the conus medullaris is rare but significant. Surgical resection can improve motor function, while combined therapy (surgery plus radiotherapy) is effective in improving sensory manifestations and bowel/bladder functions. Despite these treatments, the median survival remains around 100 days, which is shorter compared to other types of intramedullary spinal cord metastases.

Analyzing the relationship between cerebral aneurysms and Non-oculomotor cranial nerve palsies: a systematic review.

OBJECTIVES: This study aimed to investigate the association between intracerebral aneurysms and cranial nerve (CN) palsies, focusing on nerves other than the oculomotor nerve. It sought to determine the prevalence, risk factors, and clinical outcomes of these nerve palsies and compare the effectiveness of microsurgical clipping versus endovascular coiling in restoring nerve function. METHODOLOGY: Following PRISMA guidelines, a comprehensive literature search was conducted using databases like PubMed, Scopus, and Google Scholar, covering studies from 1975 to April 2024. The inclusion criteria targeted patients with non-oculomotor nerve palsies diagnosed with cerebral aneurysms. Studies published before 1975 and non-English studies were excluded. Data extraction included study design, patient characteristics, and intervention outcomes. The Joanna Briggs Institute and Newcastle-Ottawa scales were used to assess study quality. Data were synthesized narratively and statistically analysed using SPSS v27. RESULTS: The analysis included 47 patients (53.2% female, mean age 44.8 years). The internal carotid artery (ICA) was the most common aneurysm site (44.7%), and the abducent nerve (CN VI) was most frequently affected. Ruptured aneurysms had better recovery outcomes (88.9%) than unruptured ones (66.7%). Hypertension was present in 9.2%. Unilateral aneurysms were seen in 80.9%, with 76.6% having a single nerve palsy. Non-ruptured aneurysms accounted for 58.1%, and ruptured for 41.9% of associated cranial nerve palsies. Treatment included microsurgical approaches (42.6%), endovascular approaches (34%), combined approaches (6.4%), and conservative management (17%). Recovery of the palsy was observed in 75.6%, with endovascular procedures showing higher recovery (93.3%) compared to conservative treatment (28.6%). CONCLUSION: Intracerebral aneurysms are significantly associated with non-oculomotor CN palsies. Endovascular procedures yield higher recovery rates than conservative management, particularly in ruptured aneurysms. Timely and appropriate treatment is crucial for improving nerve function recovery in these patients.

Treatment strategies for saccular anterior inferior cerebellar artery aneurysms: a systematic review.

INTRODUCTION: The anterior inferior cerebellar artery (AICA) plays a crucial role in cerebellar blood supply, and AICA aneurysms are relatively rare, comprising less than 1-1.5% of all brain aneurysms. Understanding their clinical scenarios, management approaches, and outcomes is essential. This systematic review analyzes data from 86 studies to comprehensively explore AICA aneurysms. MATERIALS AND METHODS: The process of obtaining relevant research, which includes patients with AICA aneurysms, was carried out using the PubMed, Web of Science, and Scopus databases. This review exclusively included extensive papers written in English. The search included the MeSH phrases "Anterior inferior cerebellar artery aneurysm" and "AICA aneurysm." Microsurgical and endovascular treatments were compared using statistical analysis, exploring demographics, risk factors, treatment modalities, and clinical outcomes. RESULTS: The review includes 85 case reports and one retrospective study, totaling 140 patients. The study reveals a diverse patient profile with a slight female predominance (65%), a mean age of 50.7 years, and an 82.86% prevalence of no identified risk factors. Ruptured aneurysms accounted for 55%, with microsurgery and endovascular procedures accounting for 70.71% and 27.86%, respectively. The mortality rate was 2.86%, and no significant differences were found in rebleed, recurrence, or mortality rates between treatment groups. CONCLUSION: Microsurgical and endovascular interventions demonstrate comparable effectiveness, with microsurgery showing superiority in specific situations. Therefore, tailoring treatment is crucial to individual patient needs. Subgroup analyses highlight demographic-specific trends, guiding clinicians in managing this rare pathology.

Retraction notice to "Decency in neurosurgery" [Brain Spine 4 (2024), 102744].

[This retracts the article DOI: 10.1016/j.bas.2023.102744.].

Bilateral cranioorbital foramina (Hyrtl foramina): crucial anatomical findings in the management of giant olfactory groove meningioma - a case report and literature review.

Presence of bilateral cranio-orbital foramina, AKA Hyrtl foramina is rare yet existing. They carry the risks of retinal artery emboli due to reflux embolization for the neurovascular interventionalists, navigating complexities in olfactory groove meningioma management. A 59-year-old woman with progressive frontal lobe syndrome presented a large olfactory groove meningioma primarily supplied by bilateral sphenopalatine arteries together with bilateral anterior cerebral arteries, necessitating risky preoperative embolization and meticulous resection. This case underscores the intricate nature of vascular supply in frontal skull base tumors, emphasizing the need for multidisciplinary approaches, thorough preoperative planning, and detective research to optimize treatment outcomes.

Liliequist membrane: A systematic review of history, anatomy, clinical importance, and surgical challenges.

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.

Non-colloid-cyst primary brain tumors: A systematic review of unexpected fatality.

OBJECTIVE: Primary brain tumors have the potential to present a substantial health hazard, ultimately resulting in unforeseen fatalities. Despite the enhanced comprehension of many diseases, the precise prediction of disease progression continues to pose a significant challenge. The objective of this study is to investigate cases of unexpected mortality resulting from primary brain tumors and analyze the variables that contribute to such occurrences. METHODS: This systematic review explores research on individuals diagnosed with primary brain tumors who experienced unexpected deaths. It uses PRISMA standards and searches PubMed, Google Scholar, and Scopus. Variables considered include age, gender, symptoms, tumor type, WHO grade, postmortem findings, time of death - time taken from first medical presentation or hospital admission to death, comorbidity, and risk factors. RESULTS: This study examined 46 studies to analyze patient-level data from 76 individuals with unexpected deaths attributed to intracranial lesions, deliberately excluding colloid cysts. The cohort's age distribution showed an average age of 37 years, with no significant gender preference. Headache was the most common initial symptom. Astrocytomas, meningiomas, and glioblastoma were the most common lesions, while the frontal lobe, temporal lobe, and cerebellum were common locations. Meningiomas and astrocytomas showed faster deaths within the first hour of hospital admission. CONCLUSION: The etiology of unforeseen fatalities resulting from cerebral tumors elucidates an intricate and varied phenomenon. Although unexpected deaths account for a very tiny proportion of total fatalities, it is probable that their actual occurrence is underestimated as a result of underreporting and misdiagnosis.

An In-Depth Analysis of the Artery of Salmon: Anatomy and Neurosurgical Implications.

BACKGROUND: Michel Salmon was a prominent person in the field of plastic surgery during the early 20th century. His pioneering work contributed significantly to our understanding of human anatomy, particularly with the identification of the artery of Salmon (AOS). The objective of this study is to thoroughly investigate the AOS by conducting a comprehensive literature review, providing insights into its anatomy and surgical implications. METHODS: This review was undertaken after a thorough examination of literature encompassing papers about the AOS. Right up until January 2024, databases like PubMed, ScienceDirect, and Web of Science were explored. The search was conducted using specific terms such as "Artery of Salmon," "suboccipital artery," and "vertebral artery anatomy." An in-depth assessment was conducted to examine the anatomy, and surgical significance of the AOS. RESULTS: The AOS is a branch of the V3 segment of the vertebral artery that supplies the suboccipital muscles. The ability, to identify it, is critical for distinguishing the origins of intraoperative hemorrhage. Through careful surgical intervention, the artery was able to devascularize tumors and vascular lesions. We also touched on the technical issues of its possible application in bypass operations for aneurysms of the posterior inferior cerebellar artery or vertebral artery. CONCLUSIONS: The AOS is sometimes vital in neurosurgery, facilitating precise interventions and serving as a conduit in suboccipital bypass surgeries. Understanding its variations is essential for neurosurgeons, showcasing ongoing advancements in patient care.

Ventriculoperitoneal shunt extrusion in pediatric patients, clinical patterns and therapeutic strategies: A scoping review.

Background: Ventriculoperitoneal shunts (VPSs) are frequently employed in neurosurgery to treat hydrocephalus, with a particular focus on pediatric patients. Although VPSs are commonly utilized, they are not exempt from difficulties, such as shunt extrusion. The main aim of this study is to enhance comprehension regarding the occurrence, causes contributing to, and consequences of VPS extrusion in pediatric patients. Methods: A comprehensive search approach was implemented, including electronic databases, including PubMed, Google Scholar, and Scopus, to locate pertinent articles published between January 1950 and May 2023. The utilization of keywords such as "ventriculoperitoneal shunt" and "extrusion," "ventriculoperitoneal shunt" and "migration," and "ventriculoperitoneal shunt" and "perforation" was employed. Data on patient demographics, underlying diseases, origin of extrusion, presenting symptoms, treatment, and follow-up were gathered. Statistical studies were conducted to identify potential risk factors connected with the occurrence of shunt extrusion. Results: A study analyzed 80 studies on 120 individuals with extruded VPS catheters. The majority of patients (55.8%) had symptoms such as cerebrospinal fluid leakage and irritation. Hydrocephalus was categorized into congenital (40%), obstructive (36.7%), and communicating (11.7%) groups. Catheter extrusion sites varied, with most from the anal or rectal site. Preoperative meningitis or peritonitis was present in 20% of patients. Treatments ranged from shunt removal to endoscopic third ventriculostomy, resulting in a 90% recovery rate, 1.7% mortality, and 5% follow-up loss. Conclusion: Extrusion of the distal catheter in VPSs is a critical medical situation that necessitates urgent surgical intervention. The presence of an infection raises the likelihood of complications; hence, it is vital to promptly address the issue through the administration of antibiotics and the replacement of the shunt. Timely intervention enhances results.

Pineal Apoplexy: Highlighting the Causes, Treatment, and Outcome.

BACKGROUND: Pineal apoplexy, alternatively referred to as pineal hemorrhage or pineal gland hemorrhagic stroke, is an infrequent pathologic condition characterized by bleeding within the pineal gland. In this review, we encompass the primary factors contributing to this uncommon ailment. METHODS: The retrieval of pertinent research, including patients with pineal apoplexy, was conducted through PubMed, Google Scholar, and Scopus databases. This study exclusively incorporated comprehensive articles written in the English language. The search encompassed the MeSH terms "pineal apoplexy" and "pineal hemorrhage." RESULTS: A total of 41 articles were identified, encompassing a collective sample size of 57 patients. The median age of the patients in the study was 30 years, with a range spanning from 1 to 73 years. There were 27 males, representing 47.4% of the participants. The study identified the most often reported symptoms as headache (49; 86%), nausea/vomiting (19; 33.3%), and Parinaud's syndrome (16; 28.1%). The treatment options encompass several approaches, including open resection, shunting, ventriculostomy, endoscopic aspiration, and conservative care. In the conducted study, a notable number of patients, amounting to 45 cases (78.9%), indicated an amelioration of their symptoms upon their discharge. CONCLUSION: Data from a cohort of 57 cases provide insights into symptoms, lesions, treatments, and outcomes. Management approaches range from conservative measures to surgical interventions, with prognosis hinged on timely intervention. This investigation serves as a valuable resource for clinicians and researchers, underscoring the need for early diagnosis before permanent neurologic dysfunction happens and tailored treatments for optimal outcomes in pineal apoplexy cases.

Insights into Anton Syndrome: When the brain denies blindness.

INTRODUCTION: Anosognosia, a neurological condition, involves a lack of awareness of one's neurological or psychiatric deficits. Anton Syndrome (AS), an unusual form of anosognosia, manifests as bilateral vision loss coupled with denial of blindness. This systematic review delves into 64 studies encompassing 72 AS cases to explore demographics, clinical presentations, treatments, and outcomes. MATERIALS AND METHODS: The study rigorously followed PRISMA guidelines, screening PubMed, Google Scholar, and Scopus databases without timeframe limitations. Only English human studies providing full text were included. Data underwent thorough assessment, examining patient demographics, etiological variables, and treatment modalities. RESULTS: Sixty-four studies met the stringent inclusion criteria. Examining 72 AS cases showed a median age of 55 (6 to 96 years) with no gender preference. Hypertension (34.7 %) and visual anosognosia (90.3 %) were prevalent. Stroke (40.3 %) topped causes. Management included supportive (30.6 %) and causal approaches (30.6 %). Improvement was seen in 45.8 %, unchanged in 22.2 %, and deterioration in 11.1 %. Anticoagulation correlated with higher mortality (p < 0.05). DISCUSSION: AS, an unusual manifestation of blindness, stems mainly from occipital lobe damage, often due to cerebrovascular incidents. The syndrome shares features with Dide-Botcazo syndrome and dates back to Roman times. Its causes range from strokes to rare conditions like multiple sclerosis exacerbation. Accurate diagnosis involves considering clinical presentations and imaging studies, distinguishing AS from similar conditions. CONCLUSION: This comprehensive review sheds light on AS's complex landscape, emphasizing diverse etiologies, clinical features, and treatment options. Tailored treatments aligned with individual causes are crucial. The study's findings caution against blanket anticoagulation therapy, suggesting a nuanced approach. Further research is pivotal to refine diagnostics and optimize care for AS individuals.

Recurrent artery of Heubner aneurysms in focus: insights into occurrence and current treatment paradigms.

INTRODUCTION: The recurrent artery of Heubner (RAH), also known as the medial striate artery, is the most clinically important perforator of the anterior cerebral artery. RAH aneurysm is relatively rare, with 11 cases found in the present literature review, but poses significant clinical challenges due to potential impact on cognitive and motor functions. This systematic review explored available case reports to comprehensively understand clinical presentation, diagnosis, management and outcome in RAH aneurysm. MATERIALS AND METHODS: Following PRISMA guidelines, this systematic review extensively explored RAH aneurysms, covering demographics, symptoms, diagnosis, treatments and outcomes. Comprehensive searches on PubMed, Scopus, Google Scholar, and Science Direct employed keywords such as "recurrent artery of Heubner aneurysm" and "Heubner's artery." RESULTS: After extensive screening, 9 qualifying studies were identified, with 11 patients diagnosed with rare RAH aneurysm. Median age was 55 years (standard deviation, 15.3 years), with 54.5% males. 45.5% of patients presented risk factors, including Moyamoya disease in 2 patients. The majority were classified as grade I/II on the Hunt and Hess (H&H) and World Federation of Neurological Societies (WFNS) systems. Aneurysms were predominantly located in the A1 segment, with a mean size of 4.7 mm. Treatments varied, with clipping being the most frequent (63.6%). The mortality rate was 18.2%. Clipping was associated with favorable outcomes but higher rates of infarction. CONCLUSION: This analysis highlighted the various symptoms, therapy methods and outcomes of RAH aneurysm, with A1 being the predominant origin. Future research should explore potential genetic predisposition factors and novel therapeutic interventions to address gaps in our knowledge.

Cystic dilatation of the ventriculus terminalis: A narrative review.

Introduction: The terminal ventricle, also known as the fifth ventricle, is a tiny relic cavity in the conus medullaris of the human spinal cord. Our purpose in bringing attention to this condition is to get the word out about the signs and symptoms, diagnostic hurdles, and therapeutic options available for it. Methods: All relevant studies involving patients diagnosed with ventriculus terminalis (VT) were retrieved from PubMed, Google Scholar, and Scopus. Studies published in complete English language reports were included. The terms VT, terminal ventricle, and 5th ventricle. Age, gender, presenting symptoms, magnetic resonance imaging findings, treatment, and outcome of patients with ventriculus terminalis were all included and recorded. Results: The average age of the patients was 39 years, and there were 13 men among them (14.4%). Motor deficits and sciatica were the most commonly reported symptoms in 38 and 34 patients (42.2%, 37.7%), respectively. In 48 patients (53.3%), cyst fenestration was performed, and in 25 patients (27.7%), myelotomy was performed. Fifty-eight patients (64.4%) saw a reduction in cyst size after surgery. The majority of patients reported an improvement in their symptoms in 64 cases (51.1%), with only three cases (3.3%) reporting a worsening. Conclusions: In cases where the VT is the source of symptoms such as motor, sensory, or bladder dysfunction, surgical intervention is recommended. This review compiles information from the available literature to shed light on the anatomy, clinical presentation, imaging, and treatment options for this variant. It also aims to pinpoint any potential drawbacks or restrictions connected to the surgical techniques.

Developing algae as a sustainable food source.

Current agricultural and food production practices are facing extreme stress, posed by climate change and an ever-increasing human population. The pressure to feed nearly 8 billion people while maintaining a minimal impact on the environment has prompted a movement toward new, more sustainable food sources. For thousands of years, both the macro (seaweed and kelp) and micro (unicellular) forms of algae have been cultivated as a food source. Algae have evolved to be highly efficient at resource utilization and have proven to be a viable source of nutritious biomass that could address many of the current food production issues. Particularly for microalgae, studies of their large-scale growth and cultivation come from the biofuel industry; however, this knowledge can be reasonably translated into the production of algae-based food products. The ability of algae to sequester CO2 lends to its sustainability by helping to reduce the carbon footprint of its production. Additionally, algae can be produced on non-arable land using non-potable water (including brackish or seawater), which allows them to complement rather than compete with traditional agriculture. Algae inherently have the desired qualities of a sustainable food source because they produce highly digestible proteins, lipids, and carbohydrates, and are rich in essential fatty acids, vitamins, and minerals. Although algae have yet to be fully domesticated as food sources, a variety of cultivation and breeding tools exist that can be built upon to allow for the increased productivity and enhanced nutritional and organoleptic qualities that will be required to bring algae to mainstream utilization. Here we will focus on microalgae and cyanobacteria to highlight the current advancements that will expand the variety of algae-based nutritional sources, as well as outline various challenges between current biomass production and large-scale economic algae production for the food market.

Recombinant production of a functional SARS-CoV-2 spike receptor binding domain in the green algae Chlamydomonas reinhardtii.

Recombinant production of viral proteins can be used to produce vaccine antigens or reagents to identify antibodies in patient serum. Minimally, these proteins must be correctly folded and have appropriate post-translation modifications. Here we report the production of the SARS-CoV-2 spike protein Receptor Binding Domain (RBD) in the green algae Chlamydomonas. RBD fused to a fluorescent reporter protein accumulates as an intact protein when targeted for ER-Golgi retention or secreted from the cell, while a chloroplast localized version is truncated. The ER-retained RBD fusion protein was able to bind the human ACE2 receptor, the host target of SARS-CoV-2, and was specifically out-competed by mammalian cell-produced recombinant RBD, suggesting that the algae produced proteins are sufficiently post-translationally modified to act as authentic SARS-CoV-2 antigens. Because algae can be grown at large scale very inexpensively, this recombinant protein may be a low cost alternative to other expression platforms.

Glycogen Production in Marine Cyanobacterial Strain Synechococcus sp. NKBG 15041c.

An important feature offered by marine cyanobacterial strains over freshwater strains is the capacity to grow in seawater, replacing the need for often-limited freshwater. However, there are only limited numbers of marine cyanobacteria that are available for genetic manipulation and bioprocess applications. The marine unicellular cyanobacteria Synechococcus sp. strain NKBG 15041c (NKBG15041c) has been extensively studied. Recombinant DNA technologies are available for this strain, and its genomic information has been elucidated. However, an investigation of carbohydrate production, such as glycogen production, would provide information for inevitable biofuel-related compound production, but it has not been conducted. In this study, glycogen production by marine cyanobacterium NKBG15041c was investigated under different cultivation conditions. NKBG15041c yielded up to 399 µg/ml/OD730 when cells were cultivated for 168 h in nitrogen-depleted medium (marine BG11ΔN) after medium replacement (336 h after inoculation). Cultivation under nitrogen-limited conditions also yielded an accumulation of glycogen in NKBG15041c cells (1 mM NaNO3, 301 µg/ml/OD730; 3 mM NaNO3, 393 µg/ml/OD730; and 5 mM NaNO3, 328 µg/ml/OD730) under ambient conditions. Transcriptional analyses were carried out for 13 putative genes responsible for glycogen synthesis and catabolism that were predicted based on homology analyses with Synechocystis sp. PCC 6803 (PCC6803) and Synechococcus sp. PCC7002 (PCC7002). The transcriptional analyses revealed that glycogen production in NKBG15041c under nitrogen-depleted conditions can be explained by the contribution of both increased carbon flux towards glycogen synthesis, similar to PCC6803 and PCC7002, and increased transcriptional levels of genes responsible for glycogen synthesis, which is different from the conventionally reported phenomenon, resulting in a relatively high amount of glycogen under ambient conditions compared to PCC6803 and PCC7002.

The development and characterization of an exogenous green-light-regulated gene expression system in marine cyanobacteria.

A green-light-regulated gene expression system derived from Synechocystis sp. PCC 6803 was constructed and introduced into the marine cyanobacterial strain Synechococcus sp. NKBG 15041c. The regulation system was evaluated using gfp uv as a reporter gene under red-light illumination and under simultaneous red- and green-light illumination. Expression of the reporter gene was effectively repressed under red-light illumination and increased over 10-fold by illuminating with green light. Control vectors missing either the ccaS sensor histidine kinase gene or the ccaR response regulator gene showed no detectable induction of GFPuv expression. Green-light induction of gfp uv expression was further confirmed by quantitative reverse transcription PCR. The constructed system was effective at regulating the recombinant expression of a target gene using green light in a marine cyanobacterial strain that does not naturally possess such a green-light regulation system. Thus, constructed green-light-regulated gene expression system may be used as a core platform technology for the development of marine cyanobacterial strains in which bioprocesses will be regulated by light.