Patterns of Acute Ischemic Stroke Treatment from 2010 to 2020: An Evolving Landscape in Stroke Management Following Thrombectomy Trials.

Background and Objectives: Population-based studies on stroke can help guide the care of patients with acute ischemic stroke (AIS) by providing health care communities with information regarding the current usage of stroke treatments. It remains unclear how rapidly new techniques, particularly endovascular stroke treatment (EST), are being adopted and whether there is any disparity in their availability. Although studies using the National Inpatient Sample (NIS) have been conducted, updated studies over a longer period may provide further insights. This study aimed to understand patterns of AIS treatment, discharge disposition, in-hospital mortality, and mean length of stay (LOS) for each modality from 2010 to 2020 using the NIS database. Methods: This retrospective longitudinal study was conducted using NIS data from 2010 to 2020. Patients were categorized into groups based on whether they received intravenous recombinant tissue plasminogen activator (rt-PA), EST, both rt-PA and EST (combined therapy), or supportive care alone. Demographic, socioeconomic, regional, insurance, and hospital data were also obtained. The primary outcome was the proportion of patients receiving each modality, whereas the secondary outcomes were in-hospital mortality, mean LOS, and discharge disposition. Results: The usage rates increased (p < 0.001) in all groups between 2010 and 2020 (rt-PA: 5.09% to 8.39%, EST: 0.31% to 4.40%, and rt-PA+EST: 0.46% to 1.09%). The highest increase in usage was observed for EST, with a thirteen-fold increase. Mortality decreased from 2010 to 2020 in all groups (rt-PA: 8.45% to 3.54%, EST: 25.22% to 12.50%, and rt-PA+EST: 21.12% in 2010 to 9.30%) (p < 0.001). Combination therapy demonstrated the greatest improvement, with an 11.2% reduction in absolute mortality. Mean LOS was reduced for patients who received rt-PA (6.8 to 4.8 days), EST (9.3 to 8.9 days), and combined therapy (10.0 to 8.3 days) (p < 0.001) over the study period. The proportion of patients discharged to home increased for rt-PA (29.01% to 41.85%), EST (14.13% to 17.70%), and combined therapy (12.89% to 24.29%) (p < 0.001). Overall, stroke treatment usage was higher among the higher income groups, regardless of race. Higher usage was also observed for Whites in the West and Hispanic ethnicities in the South and West. Regardless of income or treatment method, utilization rates were lower for Black patients. Utilization rates were lower for Black patients with Medicare, Medicaid, or self-pay than for White patients. Discussion: Our study demonstrated that endovascular stroke treatment continues to expand, leading to better outcomes for mortality, LOS, and home discharge. Despite these positive patterns, there are visible inequities across regions, income status, and races.

Leveraging radiomics and machine learning to differentiate radiation necrosis from recurrence in patients with brain metastases.

OBJECTIVE: Radiation necrosis (RN) can be difficult to radiographically discern from tumor progression after stereotactic radiosurgery (SRS). The objective of this study was to investigate the utility of radiomics and machine learning (ML) to differentiate RN from recurrence in patients with brain metastases treated with SRS. METHODS: Patients with brain metastases treated with SRS who developed either RN or tumor reccurence were retrospectively identified. Image preprocessing and radiomic feature extraction were performed using ANTsPy and PyRadiomics, yielding 105 features from MRI T1-weighted post-contrast (T1c), T2, and fluid-attenuated inversion recovery (FLAIR) images. Univariate analysis assessed significance of individual features. Multivariable analysis employed various classifiers on features identified as most discriminative through feature selection. ML models were evaluated through cross-validation, selecting the best model based on area under the receiver operating characteristic (ROC) curve (AUC). Specificity, sensitivity, and F1 score were computed. RESULTS: Sixty-six lesions from 55 patients were identified. On univariate analysis, 27 features from the T1c sequence were statistically significant, while no features were significant from the T2 or FLAIR sequences. For clinical variables, only immunotherapy use after SRS was significant. Multivariable analysis of features from the T1c sequence yielded an AUC of 76.2% (standard deviation [SD] ± 12.7%), with specificity and sensitivity of 75.5% (± 13.4%) and 62.3% (± 19.6%) in differentiating radionecrosis from recurrence. CONCLUSIONS: Radiomics with ML may assist the diagnostic ability of distinguishing RN from tumor recurrence after SRS. Further work is needed to validate this in a larger multi-institutional cohort and prospectively evaluate it's utility in patient care.

A Rare Case of Precocious Puberty Secondary to an LH-secreting Pituitary Adenoma.

An 8-year, 7-month-old male presented with puberty symptoms, including a 1.5-year history of facial hair with 9 months of phallic growth, body odor, and acne. Physical examination revealed phallic enlargement but only 4 mL testes bilaterally. Laboratory evaluation revealed markedly elevated LH and testosterone, but a prepubertal FSH level and minimally elevated adrenal androgens. A magnetic resonance imaging scan of the head revealed an anterior pituitary adenoma, and after the patient failed to respond to leuprolide, he was initiated on spironolactone and anastrozole to minimize pubertal progression before transsphenoidal adenomectomy. Postoperatively, the patient had rapid reduction of LH and testosterone, with subsequent cessation of pubertal progression, confirming the diagnosis of an LH-secreting pituitary adenoma despite negative immunoreactivity for LH and FSH. Functioning gonadotroph adenomas are rare and have been documented only in small case series and case reports. When active, these most commonly secrete FSH or co-secrete FSH and LH, and only very rarely result in precocious puberty. Here, we describe a rare case of an isolated LH-secreting functioning gonadotroph adenoma resulting in precocious puberty. This case reinforces the need to critically analyze departures from the typical pubertal sequence and to expand one's differential to include etiologies that can cause unbalanced secretion of gonadotropins.

Neural network for autonomous segmentation and volumetric assessment of clot and edema in acute and subacute intracerebral hemorrhages.

INTRODUCTION: Minimally-invasive surgical techniques for intracerebral hemorrhage (ICH) evacuation use imaging to guide the suction, lysing and/or drainage from the hemorrhage site via various designs. A previous international surgical study has shown that reduction of hematoma volume below 15 ml is indicative of improved long term patient outcomes. The study noted a need for tools to periodically visualize remaining clot during intervention to increase the likelihood of evacuating sufficient clot volumes without endangering rebleeds. Robust segmentation of MRI could guide surgeons and radiologists regarding remaining regions and approaches for prudent evacuation. We thus propose a Convolutional Neural Network (CNN) to identify and autonomously segment clot and peripheral edema in MR images of the brain and generate an estimate of the remaining clot volume. MATERIALS AND METHODS: We used a retrospective, locally-acquired dataset of ICH patient scans taken on 3 T MRI scanners. Three sets of ground truth manual segmentations were independently generated by two imaging scientists and one radiology fellow. Evaluation of clot age was determined based on relative contrast of hemorrhage components and reviewed by a neurosurgeon. Model accuracy was determined by pixel-wise Dice coefficient (DC) calculations between each ground truth manual segmentation and the machine-derived autonomous segmentations. RESULTS: The model produced autonomous segmentations of clot core with an average DC of 0.75 ± 0.21 relative to manual segmentations of the same scans. For edema, it produced segmentations with an average DC of 0.68 ± 0.16 relative to manual. From these pixel-wise segmentations, clot volume can be calculated. Model-produced segmentations underestimated clot volumes by an average of 17% relative to ground-truth. CONCLUSION: The machine learning models were able to identify and segment volumes of ICH components swiftly and accurately.

Large vertebral artery pseudoaneurysm masquerading as a schwannoma: illustrative case.

BACKGROUND: Extracranial vertebral aneurysms or pseudoaneurysms are rare and result primarily from trauma. Large pseudoaneurysms can masquerade as mass lesions, making it challenging to identify the correct diagnosis. OBSERVATIONS: This is a case report in which a large vertebral pseudoaneurysm posed as a schwannoma and biopsy was attempted. It was later identified as a vascular lesion and treated appropriately with no complications. LESSONS: Vascular etiologies should always be included in the differential diagnosis of spine and nerve pathologies especially lesions that are in the vicinity of major vascular channels such as the transverse foramina of the cervical spine.

Tectal region papillary neuroglial tumour: a case report.

Papillary glioneuronal tumor (PGNT) is a rare central nervous system neoplasm. Of reported cases, the vast majority are located in the frontal and temporal lobes. We present the case of a 39-year-old male who presented with a one day history of gait disturbance following chemotherapy treatment for metastatic rectal adenocarcinoma. Following MRI of the head showed a tectal mass. Following an occipital interhemispheric craniotomy for tumor resection, final pathology was diagnostic of a papillary neuroglial tumor, WHO grade I. To the best or out knowledge this is the only report of it arising from the tectal plate.

Treatment of an aberrant inferior temporal artery aneurysm arising off the proximal cavernous segment of the internal carotid artery.

We report the clinical details, imaging findings, and management of a 41-year-old female who presented with 6th cranial nerve palsy from a right proximal cavernous segment internal carotid artery aneurysm arising distal to the branch point of an aberrant inferior temporal artery. Although rare, aberrant branches arising off the proximal ICA may supply the cerebral cortex. Careful evaluation prior to surgical intervention in this setting may reduce the incidence of ischemic complications.

Real-time trajectory guide tracking for intraoperative MRI-guided neurosurgery.

PURPOSE: In current intraoperative MRI (IMRI) methods, an iterative approach is used to aim trajectory guides at intracerebral targets: image MR-visible features, determine current aim by fitting model to image, manipulate device, repeat. Infrequent updates are produced by such methods, compared to rapid optically tracked stereotaxy used in the operating room. Our goal was to develop a real-time interactive IMRI method for aiming. METHODS: The current trajectory was computed from two points along the guide's central axis, rather than by imaging the entire device. These points were determined by correlating one-dimensional spokes from a radial sequence with the known cross-sectional projection of the guide. The real-time platform RTHawk was utilized to control MR sequences and data acquisition. On-screen updates were viewed by the operator while simultaneously manipulating the guide to align it with the planned trajectory. Accuracy was quantitated in a phantom, and in vivo validation was demonstrated in nonhuman primates undergoing preclinical gene ( n = 5 $$ n=5 $$ ) and cell ( n = 4 $$ n=4 $$ ) delivery surgeries. RESULTS: Updates were produced at 5 Hz In 10 phantom experiments at a depth of 48 mm, the cannula tip was placed with radial error of (min, mean, max) = (0.16, 0.29, 0.68) mm. Successful in vivo delivery of payloads to all 14 targets was demonstrated across nine surgeries with depths of (min, mean, max) = (33.3, 37.9, 42.5) mm. CONCLUSION: A real-time interactive update rate was achieved, reducing operator fatigue without compromising accuracy. Qualitative interpretation of images during aiming was rendered unnecessary by objectively computing device alignment.

Academics versus the Internet: Evaluating the readability of patient education materials for cerebrovascular conditions from major academic centers.

Background: Health literacy profoundly impacts patient outcomes as patients with decreased health literacy are less likely to understand their illness and adhere to treatment regimens. Patient education materials supplement in-person patient education, especially in cerebrovascular diseases that may require a multidisciplinary care team. This study aims to assess the readability of online patient education materials related to cerebrovascular diseases and to contrast the readability of those materials produced by academic institutions with those of non-academic sources. Methods: The readability of online patient education materials was analyzed using Flesch-Kincaid Grade Level (FKGL) and Flesch Reading Ease (FRE) assessments. Readability of academic-based online patient education materials was compared to nonacademic online patient education materials. Online patient education materials from 20 academic institutions and five sources from the web were included in the analysis. Results: Overall median FKGL for neurovascular-related patient online education documents was 11.9 (95% CI: 10.8-13.1), reflecting that they are written at a 12th grade level, while the median FRE was 40.6 (95% CI: 34.1-47.1), indicating a rating as "difficult" to read. When comparing academic-based online patient education materials to other internet sources, there was no significant difference in FRE and FKGL scores (P = 0.63 and P = 0.26 for FKGL and FRE, respectively). Conclusion: This study demonstrates that online patient education materials pertaining to cerebrovascular diseases from major academic centers and other nonacademic internet sites are difficult to understand and written at levels significantly higher than that recommended by national agencies. Both academic and nonacademic sources reflect this finding equally. Further study and implementation are warranted to investigate how improvements can be made.

Candida Shunt Infection Causing Arachnoiditis and Hydrocephalus: A Case Report.

Arachnoiditis is a relatively rare condition and can result in long-term chronic and debilitating complications if not diagnosed early and treated properly. However, diagnosis of arachnoiditis is rare and knowledge of potential causes of this condition is still sparse. Current known causes of arachnoiditis include infections, trauma, spinal tumors, and iatrogenic causes induced via neurological interventions. Here, we present a case of a 65-year-old female who presented with arachnoiditis caused by Candida albicans infection from a contaminated ventriculoperitoneal (VP) shunt, placed following the development of hydrocephalus from subarachnoid hemorrhage. During her initial assessment, the possibility of arachnoiditis was raised after spinal magnetic resonance imaging (MRI) due to leg weakness and spasms with bladder dysfunction. However, further workup was not pursued after a normal spinal angiogram and lack of constitutional symptoms. She presented six months later with symptoms of fever and lower abdominal pain. She was diagnosed with fungal arachnoiditis after a computerized tomography (CT) of the abdomen showed thickening of the fascia around the shunt catheter and fluid collections near the tip of the shunt in the abdominal cavity after hospitalization. The diagnosis was made after an ultrasound-guided tap of the same area revealed budding yeast and cerebrospinal fluid (CSF) showed growths of Candida albicans. Her shunt was removed, and she received intravenous (IV) antifungals and recovered. MRI should be considered with clinical presentations that are characteristic of arachnoiditis. Symptoms from fungal infections are usually dramatic; however, in some instances as in this case, they may follow a more progressive course. The patient should be extensively evaluated for infection, especially fungal, in interventions involving device placement even when minimally, but persistently, symptomatic.

Surgical Indications and Options for Hypertensive Hemorrhages.

The morbidity and mortality associated with spontaneous intracerebral haemorrhage high, with 40% reported mortality at 1 month and fewer than 40% of patients regaining functional independence. Despite advances made in the treatment of ischemic stroke, similar improvements have not been seen with intracerebral hemorrhage. Medical control of blood pressure and intracranial pressure, among other factors, are key to management. The impact of surgical intervention is less clear. This article reviews the data surrounding the surgical management of intracerebral hemorrhage, including open and minimally invasive techniques and discusses the controversies and future directions surrounding surgical management.

Delayed spinal epidural hematoma following T1 chance fracture: An illustrative case and review of the literature.

Background: A Chance fracture is a traumatic fracture of the thoracic or lumbar spine that occurs secondary to a flexion-distraction injury. Although patients with chance fractures rarely present with neurologic deficits, a subset may become symptomatic from spinal epidural hematomas (SEH) warranting emergent decompressive surgery. Case Description: An 87-year-old female on anticoagulation presented with a T1 Chance fracture after a fall. She was originally neurologically intact, but became paraplegic over the next 10 h. When the cervical/thoracic magnetic resonance revealed a SEH markedly compressing the cord between the C7-T1 levels, she underwent an emergent decompression; she also had a C5-T4 instrumented fusion. Postoperatively, she regained lower limb function, but expired on postoperative day 5 due to respiratory complications likely attributed to the prolonged surgery for the spinal instrumentation. Conclusion: Delayed SEH rarely occur following spinal Chance fractures. Here, an 87-year-old female on anticoagulation developed the 10-h delayed onset of a SEH with paraplegia attributed to a T1 Chance fracture at the C7-T1 level. Although she regained neurological function following the emergent decompression, she expired 5 days later likely due to the extended operative time/blood loss from the C5-T4 fusion that could have been avoided.

Interleukin-34 Reprograms Glycolytic and Osteoclastic Rheumatoid Arthritis Macrophages via Syndecan 1 and Macrophage Colony-Stimulating Factor Receptor.

OBJECTIVE: In rheumatoid arthritis (RA), elevated serum interleukin-34 (IL-34) levels are linked with increased disease severity. IL-34 binds to 2 receptors, macrophage colony-stimulating factor receptor (M-CSFR) and syndecan 1, which are coexpressed in RA macrophages. Expression of both IL-34 and syndecan 1 is strikingly elevated in the RA synovium, yet their mechanisms of action remain undefined. This study was undertaken to investigate the mechanism of action of IL-34 in RA. METHODS: To characterize the significance of IL-34 in immunometabolism, its mechanism of action was elucidated in joint macrophages, fibroblasts, and T effector cells using RA and preclinical models. RESULTS: Intriguingly, syndecan 1 activated IL-34-induced M-CSFR phosphorylation and reprogrammed RA naive cells into distinctive CD14+CD86+GLUT1+ M34 macrophages that expressed elevated levels of IL-1ß, CXCL8, and CCL2. In murine M34 macrophages, the inflammatory phenotype was accompanied by potentiated glycolytic activity, exhibited by transcriptional up-regulation of GLUT1, c-Myc, and hypoxia-inducible factor 1α (HIF-1α) and amplified pyruvate and l-lactate secretion. Local expression of IL-34 provoked arthritis by expanding the glycolytic F4/80-positive, inducible nitric oxide synthase (iNOS)-positive macrophage population, which in turn attracted fibroblasts and polarized Th1/Th17 cells. The cross-talk between murine M34 macrophages and Th1/Th17 cells broadened the inflammatory and metabolic phenotypes, resulting in the expansion of IL-34 pathogenicity. Consequently, IL-34-instigated joint inflammation was alleviated in RAG-/- mice compared to wild-type mice. Syndecan 1 deficiency attenuated IL-34-induced arthritis by interfering with joint glycolytic M34 macrophage and osteoclast remodeling. Similarly, inhibition of glycolysis by 2-deoxy-d-glucose reversed the joint swelling and metabolic rewiring triggered by IL-34 via HIF-1α and c-Myc induction. CONCLUSION: IL-34 is a novel endogenous factor that remodels hypermetabolic M34 macrophages and facilitates their cross-regulation with T effector cells to advance inflammatory bone destruction in RA.

Atypical Teratoid/Rhabdoid Tumor of the Cerebellum in an Adult: Case Report and Literature Review.

BACKGROUND: Atypical teratoid/rhabdoid tumor (AT/RT) is a rare tumor that is most frequently encountered in the pediatric patient population. AT/RT accounts for approximately 1%-2% of all pediatric central nervous system tumors and roughly 10%-20% of tumors in patients younger than 3 years of age. While AT/RT has been encountered in the adult population, the vast majority of the cases reported occur in the supratentorial space. In the existing literature, only 3 adult cases that arise from the cerebellum have ever been reported. CASE DESCRIPTION: A 38-year-old female presented with 6 months of worsening nausea, emesis, vertigo, diplopia, and coordination difficulty. Magnetic resonance imaging revealed a T1 avidly contrast-enhancing mass, composed of both cystic and solid areas, extending from the cerebellum into the fourth ventricle. Following a gross total resection, surgical pathology was consistent with AT/RT, with tumor cell loss of integrase interactor-1 (INI-1) observed via immunohistochemical staining. CONCLUSIONS: This case represents just the fourth ever reported case of AT/RT arising from the cerebellum in an adult and the oldest reported age to date of a cerebellar AT/RT occurring in a female. Due to the paucity of reported adult AT/RT cases, little is known about adults with AT/RT. Further reports will function to improve the general understanding of AT/RT in the adult population.

Difference in imaging biomarkers between transient and permanent neurological deficits after endovascular treatment of cerebrovascular aneurysms.

OBJECTIVE: The literature suggests that blood-brain barrier disruption (BBBD) plays a significant role in the development of neurological events in patients with diffusion-weighted imaging (DWI) that is negative for lesions. In this prospective, single-center cohort study, the authors compared the imaging characteristics of patients suffering transient neurological events (TNEs) with those in patients suffering permanent neurological events (PNEs) after having undergone elective embolization of unruptured intracranial aneurysms. METHODS: This prospective cohort study was conducted between July 2016 and June 2019. Inclusion criteria were adults undergoing elective neuroendovascular procedures and the absence of contraindications to MRI. All subjects underwent brain MRI including postcontrast FLAIR (pcFLAIR) sequences for evaluation of BBBD within 24 hours postprocedure. RESULTS: In total, 128 patients harboring 133 unruptured aneurysms were enrolled, 109 of whom (85.2%) showed some degree of BBBD on pcFLAIR MRI and 50 of whom (39.1%) suffered an ischemic insult per DWI. In total, 23 patients (18%) suffered neurological complications, 16 of which (12.5%) were TNEs and 7 of which (5.5%) were PNEs. The median extent of BBBD was focal in asymptomatic patients as compared to hemispheric and lobar in the TNE and PNE groups, respectively (p < 0.001). The American Society of Anesthesiologists physical status classification predicted the extent of BBBD (p = 0.046). Lesions on DWI were noted in 34 asymptomatic patients (32.4%) compared to 9 patients (56.3%) with TNEs and all 7 patients (100%) with PNEs (p < 0.001). The median number of DWI lesions was 0 (range 0-18 lesions) in the asymptomatic group compared to 1.5 (range 0-8 lesions) and 8 (range 1-13 lesions) in the TNE and PNE groups, respectively (p < 0.001). Smoking (p = 0.008), older age (p = 0.002), and longer surgery (p = 0.006) were positively associated with the number of lesions on DWI. On multivariate analysis, intraarterial verapamil (p = 0.02, OR 8.01, 95% CI 1.35-47.43) and extent of BBBD (p < 0.001, OR 58.58, 95% CI 9.48-361.84) were positively associated with the development of TNEs, while intravenous infusion of midazolam during surgery (p = 0.02, OR 6.03, 95% CI 1.29-28.20) was negatively associated. An increased number of lesions on DWI was the only significant predictor for the development of PNEs (p < 0.001, OR 49.85, 95% CI 5.56-447.10). CONCLUSIONS: An increasing extent of BBBD was associated with the development of TNEs, whereas an increasing number of lesions on DWI was significantly associated with the development of PNEs. BBBD imaging using pcFLAIR may serve as a valuable biomarker for detecting subtle cerebral ischemia and stratifying the risk for ischemic events.

Intraoperative Shortening of Aneurysm Clips: Revisiting an Old Technique in a New Era.

BACKGROUND: It can sometimes be challenging to find a suitable clip to treat an unusual aneurysm, or when the surrounding anatomy is unusual, especially in resource-limited environments. We describe a method to modify aneurysm clips based on the method originated by Sugita et al in 1985. Herein clip modification (Clip-Mod) is used to treat anatomically difficult anterior communicating artery aneurysms. METHODS: The Department of Neurological Surgery database was reviewed to find aneurysm patients treated using modified aneurysm clips. Clip-Mod was performed during surgery by shortening the tines of titanium aneurysm clips by abrasion applied from the side of a standard 3-mm surgical diamond drill bit under constant irrigation. Note that the thickness of the tines and the clip spring were not modified or contacted by the drill. RESULTS: Four cases used modified aneurysm clips, from 648 total clip-treated aneurysms (0.6%) by 2 surgeons over a 14-year period. Three patients presented with subarachnoid hemorrhages that were determined to be due to anterior communicating artery aneurysms. One patient presented with an incidental unruptured anterior communicating artery aneurysm. All 4 patients were treated with 3-mm titanium clips shortened intraoperatively to 1- to 2-mm lengths, to achieve aneurysm obliteration without stenosing parent or perforating vessels. CONCLUSIONS: All 4 patients have done well clinically with no reoccurrences after 2-6 years' follow-up, which included angiographic evaluation. The use of this "Clip-Mod" technique thus appears useful for anterior communicating artery aneurysms. Clip-Mod could also be considered for treating other aneurysms when the "perfect" length clip is not available.

Effect of aneurysm morphologic parameters on occlusion rates following pipeline embolization.

OBJECTIVE: Treatment failures with the use of Pipeline Embolization Device (PED) continue to be observed in up to 18% of patients in large case series. Adjunctive coiling and layering of multiple devices have been shown to improve occlusion rates; however, the optimal treatment strategy with the use of PED has not been established. The purpose of this study is to identify morphological characteristics predictive of treatment failure after PED. PATIENT AND METHODS: A case control design was used to evaluate the association of aneurysm morphologic parameters with failure after PED placement. Retrospective analysis of patients undergoing PED for elective aneurysm treatment between 2014 and 2017 was performed. Patients who underwent PED placement with at least 12 months follow-up using conventional cerebral angiography were included for further review. RESULTS: 84 patients met inclusion criteria for further analysis. ten patients (11.9%) experienced treatment failure defined by retained flow within the aneurysm and of those eight patients (9.5%) required additional retreatment. On multivariate analysis decreasing aspect ratio and increasing neck width were significant parameters that predicted treatment failure. CONCLUSION: Aneurysms with small aspect ratio and large neck width may be more likely to experience treatment failure after PED embolization. This subset of aneurysms may therefore benefit from adjunctive coiling to improve occlusion rates. Future prospective studies are needed to validate these findings.

Predictors of Impaired Cerebral Perfusion After Flow Diversion Therapy.

BACKGROUND: Flow-diverting stents (FDS) are relatively safe and highly efficacious in treating cerebral aneurysms; however, a small subset of patients experience devastating hemorrhagic complications owing to presumed alterations in local aneurysm and distal cerebral blood flow. The downstream effects of FDS on distal cerebral blood flow is not well understood, but isolated reports of hyperperfusion injury have been described in the literature. We investigate the incidence and clinical factors contributing to abnormal cerebral blood flow after FDS placement. METHODS: A retrospective analysis of patients undergoing FDS for elective aneurysm treatment between 2014-2017 was performed. Patients who underwent perfusion imaging within 24-hours posttreatment were included for further analysis. Univariate and multivariate analyses were performed to assess the impact of multiple variables on the postoperative perfusion changes. RESULTS: A total of 69 patients underwent FDS therapy to treat unruptured intracranial aneurysms. Thirteen patients (18.8%) developed abnormal perfusion changes. A significant difference of the median was found in aneurysm projection width, depth, neck width, calculated approximate volume, and size ratio between the hypoperfused, normal, and hyperperfusion cases. On multivariate analysis, history of smoking (P = 0.0117), and approximate calculated volume (P = 0.0145) were significant predictors of hyperperfusion identified on posttreatment imaging. CONCLUSIONS: This study yielded several novel findings. We demonstrate that cerebral blood flow alterations will occur in a significant subset of patients undergoing FDS treatment. We also provide new evidence that aneurysm volume and history of smoking may predict the developing of postoperative perfusion anomalies. Future studies are needed to evaluate the clinical ramifications of cerebral blood flow disruption in large prospective studies.

Differences in Pressure Within the Sac of Human Ruptured and Nonruptured Cerebral Aneurysms.

BACKGROUND: Hemodynamics plays a critical role in the development, growth, and rupture of intracranial aneurysms. This data could be vital in determining individual aneurysm rupture risk and could facilitate our understanding of aneurysms. OBJECTIVE: To present the largest prospective cross-sectional cohort study of intrasaccular pressure recordings of ruptured and nonruptured intracranial aneurysms and describe the hemodynamic differences that exist between ruptured and nonruptured aneurysms. METHODS: During endovascular treatment, a standard 1.8-Fr 200 m length microcatheter was navigated into the dome of the aneurysm prior to coil embolization. With the microcatheter centralized within the dome of the aneurysm, an arterial pressure transducer was attached to the proximal end of the microcatheter to measure the stump pressure inside the aneurysm dome. RESULTS: In 68 aneurysms (28 ruptured, 40 nonruptured), we observed that ruptured cerebral aneurysms had a lower systolic and mean arterial pressure compared to nonruptured cohort (P = .0008). Additionally, the pulse pressures within the dome of ruptured aneurysms were significantly more narrow than that of unruptured aneurysms (P = .0001). These findings suggest that there may be an inherent difference between ruptured and nonruptured aneurysms and such recordings obtained during routine digital subtraction angiography could potentially become a widely applied technique to augment risk stratification of aneurysms. CONCLUSION: Our preliminary data present new evidence distinguishing ruptured from unruptured aneurysms that may have a critical role as a predictive parameter to stratify the natural history of nonruptured intracranial aneurysms and as a new avenue for future investigation.