Long-term neuropsychiatric complications of aneurysmal subarachnoid hemorrhage: a narrative review.

This review focuses on the often-neglected long-term neuropsychiatric consequences of aneurysmal subarachnoid hemorrhage (aSAH), beyond traditional randomized trial outcomes of mortality and retreatment. While current guidelines recommend screening for these sequalae, it may not be routinely practiced. This review will underscore the prevalence and management of common neuropsychiatric sequalae, including anxiety, depression, cognitive dysfunction, headaches, seizures, and sexual dysfunction, all of which can significantly impact the quality of life of survivors of aSAH. We emphasize the critical role neurointerventionalists can play by going beyond the customary practice of radiological monitoring for treated aneurysms by screening for and helping guide management of these common neuropsychiatric complications.

Pediatric Congenital Anterior Skull Base Encephaloceles and Surgical Management: A Comparative Review of 22 Patients Treated With Transnasally, Transcranially, or Combined Approach With a Review of the Literature.

BACKGROUND AND OBJECTIVES: Anterior basal encephaloceles are considered a rare entity and are often associated with midline cerebral abnormalities. Those with a large skull base defect and herniation of brain parenchyma in the neonate or young infant present unique challenges for surgical management. METHODS: We analyzed the neurosurgical administrative and operative databases between 1986 and 2022 to determine clinical presentation, operative approach, and outcome of basal encephaloceles. RESULTS: Over the 36-year period, 27 pediatric anterior basal encephaloceles were managed, of which 22 had full documentation and images allowing comprehensive review. Mean age at presentation was 5 years (SD 4.94). The majority were transethmoidal encephaloceles (59%), followed by the transsphenoidal-sphenoethmoidal type (32%). Overall, 91% were managed surgically by a transcranial, endoscopic, or combined approach. Four children required subsequent procedures, predominantly for persistent cerebrospinal fluid leak. No significant differences in proportion of patients requiring interval/revision surgery after initial conservative, endoscopic endonasal, or transcranial surgery was identified. Neither age at surgery nor size of the defect on computed tomography scan was associated with the need for revision surgery. Size of cranial defect was significantly smaller in the endoscopic group (P = .01). There was a historic tendency for younger children with larger defects to have a transcranial approach. With the addition of endoscopic skull base expertise, smaller defects in older children were more recently treated endoscopically. CONCLUSION: Basal encephaloceles are rare and complex lesions and are optimally managed within a skull base multidisciplinary team able to provide multiple approaches. Large skull base defects with brain parenchymal involvement often require a transcranial or combined transcranial-endoscopic approach.

Epidural Spinal Cord Stimulation for Spasticity: a Systematic Review of the Literature.

OBJECTIVE: Spasticity is a form of muscle hypertonia secondary to various diseases, including traumatic brain injury, spinal cord injury, cerebral palsy, and multiple sclerosis. Medical treatments are available; however, these often result in insufficient clinical response. This review evaluates the role of epidural spinal cord stimulation (SCS) in the treatment of spasticity and associated functional outcomes. METHODS: A systematic review of the literature was performed using the Embase, CENTRAL, and MEDLINE databases. We included studies that used epidural SCS to treat spasticity. Studies investigating functional electric stimulation, transcutaneous SCS, and animal models of spasticity were excluded. We also excluded studies that used SCS to treat other symptoms such as pain. RESULTS: Thirty-four studies were included in the final analysis. The pooled rate of subjective improvement in spasticity was 78% (95% confidence interval, 64%-91%; I2 = 77%), 40% (95% confidence interval, 7%-73%; I2 = 88%) for increased H-reflex threshold or decreased Hoffman reflex/muscle response wave ratio, and 73% (65%-80%; I2 = 50%) for improved ambulation. Patients with spinal causes had better outcomes compared with patients with cerebral causes. Up to 10% of patients experienced complications including infections and hardware malfunction. CONCLUSIONS: Our review of the literature suggests that SCS may be a safe and useful tool for the management of spasticity; however, there is significant heterogeneity among studies. The quality of studies is also low. Further studies are needed to fully evaluate the usefulness of this technology, including various stimulation paradigms across different causes of spasticity.

The Development And Applications Of Augmented And Virtual Reality Technology In Spine Surgery Training: A Systematic Review.

BACKGROUND: The COVID-19 pandemic has accelerated the growing global interest in the role of augmented and virtual reality in surgical training. While this technology grows at a rapid rate, its efficacy remains unclear. To that end, we offer a systematic review of the literature summarizing the role of virtual and augmented reality on spine surgery training. METHODS: A systematic review of the literature was conducted on May 13th, 2022. PubMed, Web of Science, Medline, and Embase were reviewed for relevant studies. Studies from both orthopedic and neurosurgical spine programs were considered. There were no restrictions placed on the type of study, virtual/augmented reality modality, nor type of procedure. Qualitative data analysis was performed, and all studies were assigned a Medical Education Research Study Quality Instrument (MERSQI) score. RESULTS: The initial review identified 6752 studies, of which 16 were deemed relevant and included in the final review, examining a total of nine unique augmented/virtual reality systems. These studies had a moderate methodological quality with a MERSQI score of 12.1 + 1.8; most studies were conducted at single-center institutions, and unclear response rates. Statistical pooling of the data was limited by the heterogeneity of the study designs. CONCLUSION: This review examined the applications of augmented and virtual reality systems for training residents in various spine procedures. As this technology continues to advance, higher-quality, multi-center, and long-term studies are required to further the adaptation of VR/AR technologies in spine surgery training programs.

Delayed neurological improvement in a patient with Duret hemorrhage secondary to an acute subdural hematoma: illustrative case.

BACKGROUND: Duret hemorrhage is a rare phenomenon wherein rapid transtentorial herniation results in brainstem injury and hemorrhage. It is usually regarded as a poor prognostic factor representing irreversible and often catastrophic brain injury. The authors report an unusual case of Duret hemorrhage with spontaneous delayed neurological recovery postoperatively after surgical treatment of an acute subdural hematoma (SDH). OBSERVATIONS: The authors present the case of a 65-year-old male who initially presented to the hospital with a large acute left-sided SDH causing 1.3 cm of midline shift. He was taken urgently for a craniotomy, with no significant intraoperative swelling or visible contusions. Postoperative imaging revealed an unexpected pontine hyperdensity concerning for a Duret hemorrhage. He initially had no neurological improvement; however, at 3 weeks postoperatively, he gradually recovered and was able to follow commands and was extubated. At 10 weeks after surgery, his Glasgow Coma Scale score improved to 15, with mild residual left hemiparesis. LESSONS: This case challenges a classic dogma that Duret hemorrhage carries a universally poor outcome. In select cases, patients can make meaningful recoveries in a delayed fashion. The lack of intraoperative contusions and swelling may have contributed to this patient's recovery.

Intraoperative intraarterial indocyanine green video-angiography for disconnection of a perimedullary arteriovenous fistula: illustrative case.

BACKGROUND: Intraarterial (IA) indocyanine green (ICG) angiography is an intraoperative imaging technique offering special and temporal characterization of vascular lesions with very fast dye clearance. The authors' aim is to demonstrate the use of IA ICG angiography to aid in the surgical treatment of a perimedullary thoracic arteriovenous fistula (AVF) in a hybrid operating room (OR). OBSERVATIONS: A 31-year-old woman with a known history of spinal AVF presented with 6 weeks of lower-extremity weakness, gait imbalance, and bowel/bladder dysfunction. Magnetic resonance imaging revealed an extensive series of flow voids across the thoracic spine, most notably at T11-12. After partial embolization, she was taken for surgical disconnection in a hybrid OR. Intraoperative spinal digital subtraction angiography was performed to identify feeding vessels. When the target arteries were catheterized, 0.05 mg of ICG in 2 mL of saline was injected, and the ICG flow in each artery was recorded using the microscope. With an improved surgical understanding of the contributing feeding arteries, the authors achieved complete in situ disconnection of the AVF. LESSONS: IA ICG angiography can be used in hybrid OR settings to illustrate the vascular anatomy of multifeeder perimedullary AVFs and confirm its postoperative disconnection with a fast dye clearance.

Non-contrast Enhancing Group A Streptococcus Subdural Empyema: An Illustrative Case Report of a Potential Radiographic Pitfall.

Subdural empyemas (SDEs) are an uncommon complication of intracranial infection, typically presenting as a hypodense collection with peripheral contrast enhancement. Herein, we report two rare cases of SDE without contrast enhancement, both secondary to group A streptococcus. The first is a 27-year-old previously healthy female, at 27 weeks of gestational age who presented with fever, headache, neurological decline, and blood cultures positive for gram-positive cocci. The second case is a previously healthy 48-year-old male who presented with left-sided otalgia, fever, headache, and precipitous decline in altered mental status and hemiplegia. Computed tomography (CT) and magnetic resonance imaging (MRI) in both cases showed a subdural collection without contrast enhancement and without diffusion restriction. Despite appearances similar to subdural effusion, because of a heightened suspicion due to clinical decline, both were taken to surgery for irrigation and debridement which confirmed SDE. Both patients were treated with six weeks of intravenous antibiotics and eventually recovered without neurological deficits. SDEs are uncommon but clinically significant phenomena. These two cases demonstrate that SDEs in rare circumstances may present as non-enhancing subdural collections. Missing the diagnosis of SDE can have significant consequences to patient morbidity and mortality and as such, it not be excluded based on radiographic findings alone.

Sinus pericranii in the setting of a posterior fossa pilocytic astrocytoma: illustrative case.

BACKGROUND: Sinus pericranii (SP) is a rare vascular anomaly, with an uncertain etiology. Often discovered as superficial lesions, they can be primary or secondary in nature. Herein, we report a rare case of SP in the setting of a large posterior fossa pilocytic astrocytoma associated with a significant venous network. OBSERVATIONS: A 12-year-old male presented with acute clinical deterioration in extremis with a 2-month history of lethargy and headaches. Outside plain computed tomography imaging revealed a large posterior fossa cystic lesion, probably a tumor, with severe hydrocephalus. There was also a midline small skull defect at the opisthocranion, without visible vascular anomalies. An external ventricular drain was placed with rapid recovery. Contrast imaging revealed a large midline SP emanating from occipital bone with a large intraosseous, and subcutaneous venous plexus in the midline draining inferiorly into venous plexus around the craniocervical junction. A posterior fossa craniotomy without contrast imaging could have resulted in catastrophic hemorrhage. A small modified off-center craniotomy provided access to the tumor with a gross total excision. LESSONS: SP is a rare but significant phenomenon. Its presence does not necessarily preclude resection of underlying tumors, provided that a careful preoperative assessment of the venous anomaly is undertaken.

Nucleus accumbens: a systematic review of neural circuitry and clinical studies in healthy and pathological states.

OBJECTIVE: The nucleus accumbens (NAcc) of the ventral striatum is critically involved in goal- and reward-based behavior. Structural and functional abnormalities of the NAcc or its associated neural systems are involved in neurological and psychiatric disorders. Studies of neural circuitry have shed light on the subtleties of the structural and functional derangements of the NAcc across various diseases. In this systematic review, the authors sought to identify human studies involving the NAcc and provide a synthesis of the literature on the known circuity of the NAcc in healthy and diseased states, as well as the clinical outcomes following neuromodulation. METHODS: A systematic review was conducted using the PubMed, Embase, and Scopus databases. Neuroimaging studies that reported on neural circuitry related to the human NAcc with sample sizes greater than 5 patients were included. Demographic data, aim, design and duration, participants, and clinical and neurocircuitry details and outcomes of the studies were extracted. RESULTS: Of 3591 resultant articles, 123 were included. The NAcc and its corticolimbic connections to other brain regions, such as the prefrontal cortex, are largely involved in reward and pain processes, with distinct functional circuitry between the shell and core in healthy patients. There is heterogeneity between clinical studies with regard to the NAcc indirect targeting coordinates, methods for postoperative confirmation, and blinded trial design. Neuromodulation studies provided promising clinical results in the context of addiction and substance misuse, obsessive-compulsive disorder, and mood disorders. The most common complications were impaired memory or concentration, and a notable serious complication was hypomania. CONCLUSIONS: The functional diversity of the NAcc highlights the importance of studying the NAcc in healthy and pathological states. The results of this review suggest that NAcc neuromodulation has been attempted in the management of diverse psychiatric indications. There is promising, emerging evidence that the NAcc may be an effective target for specific reward- or pain-based pathologies with a reasonable risk profile.

Microvessel stenosis, enlarged perivascular spaces, and fibrinogen deposition are associated with ischemic periventricular white matter hyperintensities.

Periventricular white matter hyperintensities (pvWMH) are neuroimaging abnormalities surrounding the lateral ventricles that are apparent on magnetic resonance imaging (MRI). They are associated with age, neurodegenerative disease, and cerebrovascular risk factors. While pvWMH ultimately represent a loss of white matter structural integrity, the pathological causes are heterogeneous in nature, and currently, cannot be distinguished using neuroimaging alone. pvWMH could occur because of a combination of small vessel disease (SVD), ependymal loss, blood-brain barrier dysfunction, and microgliosis. In this study we aimed to characterize microvascular stenosis, fibrinogen extravasation, and microgliosis within pvWMH with and without imaging evidence of periventricular infarction. Using postmortem neuroimaging of human brains (n = 20), we identified pvWMH with and without periventricular infarcts (PVI). We performed histological analysis of microvessel stenosis, perivascular spaces, microgliosis, and immunohistochemistry against fibrinogen as a measure of serum protein extravasation. Herein, we report distinctions between pvWMH with and without periventricular infarcts based on associations with microvessel stenosis, enlarged perivascular spaces, and fibrinogen IHC. Microvessel stenosis was significantly associated with PVI and with cellular deposition of fibrinogen in the white matter. The presence of fibrinogen was associated with PVI and increased number of microglia. These findings suggest that neuroimaging-based detection of infarction within pvWMH may help distinguish more severe lesions, associated with underlying microvascular disease and BBB dysfunction, from milder pvWMH that are a highly frequent finding on MRI.

Third Nerve Palsy Due to Intracranial Aneurysms and Recovery after Endovascular Coiling.

INTRODUCTION: The modality of treatment of third nerve palsy (TNP) associated with intracranial aneurysms remains controversial. While treatment varies with the location of the aneurysm, microsurgical clipping of PComm aneurysms has generally been the traditional choice, with endovascular coiling emerging as a reasonable alternative. METHODS: Patients with TNP due to an intracranial aneurysm who subsequently underwent treatment at a mid-sized Canadian neurosurgical center over a 15-year period (2003-2018) were examined. RESULTS: A total of 616 intracranial aneurysms in 538 patients were treated; the majority underwent endovascular coiling with only 24 patients treated with surgical clipping. Only 37 patients (6.9%) presented with either a partial or complete TNP and underwent endovascular embolization; of these, 17 presented with a SAH secondary to intracranial aneurysm rupture. Aneurysms associated with TNP included PComm (64.9%), terminal ICA (29.7%), proximal MCA (2.7%), and basilar tip (2.7%) aneurysms. In general, smaller aneurysms and earlier treatment were provided for patients for ruptured aneurysms with a shorter mean interval to TNP recovery. In the endovascularly treated cohort initially presenting with TNP, seven presented with a complete TNP and the remaining were partial TNPs. TNP resolved completely in 20 patients (55.1%) and partially in 10 patients (27.0%). Neither time to coiling nor SAH at presentation were significantly associated with the recovery status of TNP. CONCLUSION: Endovascular coil embolization is a viable treatment modality for patients presenting with an associated cranial nerve palsy.

Paralysie du troisième nerf en raison d'un anévrisme intracrânien et rétablissement après la pose d'une bobine endovasculaire. INTRODUCTION: Les modalités de traitement de la paralysie du troisième nerf (PTN) associée aux anévrismes intracrâniens demeurent controversées. Bien que les traitements varient selon l'emplacement de l'anévrisme, le clippage (ou clipping) microchirurgical des anévrismes affectant les artères communicantes postérieures (ACP) est généralement apparu comme le choix le plus courant, la pose d'une bobine endovasculaire (endovascular coiling) ayant aussi émergé comme une option raisonnable. MÉTHODES: Nous nous sommes penchés sur les cas de patients atteints de PTN en raison d'un anévrisme intracrânien qui ont ensuite bénéficié d'un traitement dans un centre neurochirurgical canadien de taille moyenne, et ce, sur une période de 15 ans (2003 à 2018). RÉSULTATS: Au total, 616 anévrismes intracrâniens ayant affecté 538 patients ont été traités. La majorité d'entre eux ont bénéficié de la pose d'une bobine endovasculaire alors que seulement 24 patients ont été traités par clippage microchirurgical. Fait à noter, seuls 37 patients (6,9 %) ont donné à voir une PTN partielle ou totale et ont bénéficié d'une embolisation endovasculaire. De ce nombre, 17 ont donné à voir une hémorragie sous-arachnoïdienne (HSA) consécutive à une rupture d'anévrisme intracrânien. Les anévrismes associés à la PTN ont inclus les ACP (64,9 %), l'artère carotide interne terminale (29,7%), l'artère cérébrale moyenne proximale (2,7 %) et la pointe (tip) de l'artère basilaire (2,7 %). En général, un traitement plus précoce a été proposé aux patients victimes de plus petites ruptures d'anévrisme associées à des délais moyens de rétablissement plus courts à la suite d'une PTN. Dans la cohorte de patients ayant donné à voir des signes de PTN et ayant bénéficié d'un traitement endovasculaire, 7 d'entre eux étaient atteints d'une PTN complète alors que les autres étaient atteints d'une PTN partielle. Les signes de PTN ont fini par disparaître complètement chez 20 patients (55,1 %) et partiellement chez 10 autres (27,0 %). Ni les délais dans la pose d'une bobine endovasculaire ni des signes de HSA au moment de consulter n'ont été notablement associés au processus de rétablissement à la suite d'une PTN. CONCLUSION: En somme, il ressort que l'embolisation endovasculaire au moyen de bobines est une modalité de traitement viable pour les patients présentant une paralysie des nerfs crâniens.

Precocious White Matter Inflammation and Behavioural Inflexibility Precede Learning and Memory Impairment in the TgAPP21 Rat Model of Alzheimer Disease.

Neuroinflammation and behavioural inflexibility are both common in late adulthood but far more profound in Alzheimer disease (AD). To investigate the relationship between ageing, AD, neuroinflammation, and behavioural flexibility, male wild-type Fischer 344 (Wt) and the transgenic APP21 (TgAPP21) rats were aged to 4, 8, 13, and 22 months and evaluated for neuroinflammation and cognitive impairment. TgAPP21 rats overexpress a pathogenic variant of the human amyloid precursor protein (hAPP; Swedish and Indiana mutations) but do not spontaneously develop overt pathology related to AD. In both genotypes, learning and memory were similarly impaired in older rats. However, at 8 months of age, TgAPP21 rats demonstrated behavioural inflexibility in set shifting, reversal, and the Morris water maze, while Wt rats showed inflexibility at 13 and 22 months of age. This early inflexibility in TgAPP21 rats was accompanied by a precocious increase in microglia activation within the corpus callosum; 8- and 13-month-old TgAPP21 rats had similar levels of microglia activation as 13- and 22-month-old Wt rats, respectively. However, while neuroinflammation within the white matter continued to progress with age, behavioural inflexibility peaked in 8-month-old TgAPP21 rats; in older TgAPP21 rats, memory and learning impairments masked inflexibility. These findings suggest that the behavioural inflexibility and white matter inflammation seen in normal ageing are accelerated in AD and may precede impairments of learning and memory.

Imperata cylindrica: A Review of Phytochemistry, Pharmacology, and Industrial Applications.

Imperata cylindrica is a medicinal plant native to southwestern Asia and the tropical and subtropical zones. To date, 72 chemical constituents have been isolated and identified from I. cylindrica Among these compounds, saponins, flavonoids, phenols, and glycosides are the major constituents. Investigations of pharmacological activities of I. cylindrica revealed that this edible medicinal herb exhibits a wide range of therapeutic potential including immunomodulatory, antibacterial, antitumor, anti-inflammatory, and liver protection activities both in vivo and in vitro. The purpose of this review is to provide an overview of I. cylindrica studies until 2019. This article also intends to review advances in the botanical, phytochemical, and pharmacological studies and industrial applications of I. cylindrica, which will provide a useful bibliography for further investigations and applications of I. cylindrica in medicines and foods.

Determining the Diagnostic Utility of Lumbar Punctures in Computed Tomography Negative Suspected Subarachnoid Hemorrhage: A Systematic Review and Meta-analysis.

BACKGROUND: While headache is a common neurologic symptom, subarachnoid hemorrhage (SAH) is a rare and potentially catastrophic cause of sudden-onset severe headache. The utility of the imaging modalities and interventional procedures are central to the investigation of the causes of headache; however, they are not without their limitations, risks, and complications. METHODS: A meta-analysis in accordance with the Preferred Reporting for Systematic Reviews and Meta-analysis guidelines was conducted searching PubMed, EMBASE, and Google Scholar. Patients investigated for suspected subarachnoid hemorrhage (SAH) with a negative computed tomography (CT) and positive lumbar puncture (LP) and final diagnosis of SAH were included. The sensitivity of LP in the context of a negative CT and vsubsequent imaging confirming the cause of SAH (computed tomography angiography, magnetic resonance angiography, digital subtraction angiography [DSA]) was quantified. The pooled data were analyzed using the DerSimonian-Laid random effects model. RESULTS: Four studies with 2782 patients who presented with headache suspicious for SAH were included with an initial negative CT report and a subsequent LP to rule out SAH. All included studies had an observational prospective cohort design. A combined pooled proportion of 0.383 (0.077, 0.756); 0.086 (0.007, 0.238); and 0.22 (0.04, 0.49) for LP+, DSA+, and DSA/computed tomography angiography+ investigations were estimated with a 95% confidence interval. CONCLUSIONS: The current clinical workflow of an LP after a negative CT head for a patient presenting with a sudden-onset severe headache is observed to have a high enough proportion to warrant its continued use despite the sensitivity of modern CT scanners of ≥97%.