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Clinical characteristics of familial and sporadic pediatric cerebral cavernous malformations and outcomes

侯赛因·m·Abdall Emade Jamanah, Xiaoran Zhang, and Stephanie Greene

OBJECTIVE

Cerebral cavernous malformation (CCM) is a subtype of the vascular malformations found within the cerebral cortex. Although rare and usually discovered incidentally, these vascular abnormalities can predispose patients to spontaneous cerebral hemorrhage and subsequently lead to a myriad of neurological symptoms at presentation such as seizures and other focal neurological deficits. Although the symptoms and presentations of CCM have been adequately described in the adult population, disease characteristics and outcomes have not been extensively described in the pediatric population. Furthermore, the etiology of CCM—e.g., familial versus sporadic disease, as well as the risk factors for hemorrhage and neurological deficits and predictors of clinical and surgical outcomes—has not been adequately explored in the pediatric population. The current study attempts to classify and characterize differences in the clinical presentation, characteristics, and outcomes of CCMs between familial and sporadic cases within the pediatric population.

开云体育世界杯赔率

A retrospective review identified 131 pediatric patients with radiographically confirmed diagnosis of CCM. All pertinent demographic and clinical variables were collected. CCM lesions were characterized using T2-weighted and susceptibility-weighted angiography (SWAN) MRI. Statistical analysis was conducted using the t-test for continuous variables, whereas categorical variables were analyzed with the Fisher exact test or chi-square test. Multivariate analysis was performed using a Cox proportional hazards model with R version 4.2.0.

RESULTS

This retrospective study identified 131 pediatric CCM patients with a mean age of 8.4 years, and 54% (n = 71) were male. Twenty-seven percent (n = 35) were identified as cases with familial CCM, with the remainder classified as sporadic. The most common symptoms at presentation included generalized symptoms (headaches, nausea, and vomiting) or seizures, with a large proportion of patients also presenting as asymptomatic. No significant differences were observed in severity of symptoms between patients harboring different forms of the disease. Patients with familial CCM were noted to have a larger lesion size on average (5.26 cm3vs 1.6 cm3, p = 0.047). These patients also had a shorter progression-free follow-up interval, with 50% of patients showing progression by 888 days, compared with only 15% of sporadic CCM patients during the same period (p = 0.0019). Familial etiology of the disease and larger average lesion volume were independent, significant predictors of disease progression (p = 0.001, HR 3.29, 95% CI 1.65–6.54) and future hemorrhage (p = 0.023, HR 1.1, 95% CI 1.01–1.10), respectively.

CONCLUSIONS

Familial and sporadic CCMs tend to present with similar characteristics within the pediatric population. Patients with the familial form of the disease have an increased risk of progressive disease in terms of further hemorrhagic events.

InJournal of Neurosurgery: Pediatrics Publish Before Print

Free access

Role of matrix metalloproteinases in the pathogenesis of intracranial aneurysms

Xiaoran Zhang, William J. Ares, Philipp Taussky, Andrew F. Ducruet, and Ramesh Grandhi

Intracranial aneurysms (IAs) are a result of complex interactions between biochemical and mechanical forces and can lead to significant morbidity if they rupture and cause subarachnoid hemorrhage. This review explores the role of matrix metalloproteinases (MMPs) in the pathogenesis and progression of IAs. In addition to providing a review of the normal function of MMPs, it is intended to explore the interaction between inflammation and abnormal blood flow and the resultant pathological vascular remodeling processes seen in the development and rupture of IAs. Also reviewed is the potential for the use of MMPs as a diagnostic tool for assessment of aneurysm development and progression.

InNeurosurgical Focus Volume 47 (2019): Issue 1 (Jul 2019): Aneurysm Formation, Growth, and Rupture: The Biology and Physics of Cerebral Aneurysm

Free access

Impact of endplate-implant area mismatch on rates and grades of subsidence following stand-alone lateral lumbar interbody fusion: an analysis of 623 levels

Nitin Agarwal, Michael D. White, Xiaoran Zhang, Nima Alan, Alp Ozpinar, David J. Salvetti, Zachary J. Tempel, David O. Okonkwo, Adam S. Kanter, and D. Kojo Hamilton

OBJECTIVE

Stand-alone lateral lumbar interbody fusion (LLIF) is a useful minimally invasive approach for select spinal disorders, but implant subsidence may occur in up to 30% of patients. Previous studies have suggested that wider implants reduce the subsidence rate. This study aimed to evaluate whether a mismatch of the endplate and implant area can predict the rate and grade of implant subsidence.

开云体育世界杯赔率

作者进行了一项回顾性研究公关ospectively collected data on consecutive patients who underwent stand-alone LLIF between July 2008 and June 2015; 297 patients (623 surgical levels) met inclusion criteria. Imaging studies were examined to grade graft subsidence according to Marchi criteria. Thirty patients had radiographic evidence of implant subsidence. The endplates above and below the implant were measured.

RESULTS

A total of 30 patients with implant subsidence were identified. Of these patients, 6 had Marchi grade 0, 4 had grade I, 12 had grade II, and 8 had grade III implant subsidence. There was no statistically significant correlation between the endplate-implant area mismatch and subsidence grade or incidence. There was also no correlation between endplate-implant width and length mismatch and subsidence grade or incidence. However, there was a strong correlation between the usage of the 18-mm-wide implants and the development of higher-grade subsidence (p = 0.002) necessitating surgery. There was no significant association between the degree of mismatch or Marchi subsidence grade and the presence of postoperative radiculopathy. Of the 8 patients with 18-mm implants demonstrating radiographic subsidence, 5 (62.5%) required reoperation. Of the 22 patients with 22-mm implants demonstrating radiographic subsidence, 13 (59.1%) required reoperation.

CONCLUSIONS

There was no correlation between endplate-implant area, width, or length mismatch and Marchi subsidence grade for stand-alone LLIF. There was also no correlation between either endplate-implant mismatch or Marchi subsidence grade and postoperative radiculopathy. The data do suggest that the use of 18-mm-wide implants in stand-alone LLIF may increase the risk of developing high-grade subsidence necessitating reoperation compared to the use of 22-mm-wide implants.

InJournal of Neurosurgery: Spine Volume 33: Issue 1 (Jul 2020)

Free access

Chronic encapsulated expanding hematomas after stereotactic radiosurgery for intracranial arteriovenous malformations

Hussam Abou-Al-Shaar, Andrew Faramand, Xiaoran Zhang, Arka N. Mallela, Barton F. Branstetter, Clayton A. Wiley, and L. Dade Lunsford

OBJECTIVE

Cerebral arteriovenous malformations (AVMs) are rare cerebral vascular lesions that are associated with high morbidity and mortality from hemorrhage; however, stereotactic radiosurgery (SRS) is a well-validated treatment modality. Few reports have delineated a subgroup of patients who develop delayed chronic encapsulated expanding hematomas (CEEHs) despite angiographic evidence of AVM obliteration following radiosurgery. In this report, the authors performed a retrospective review of more than 1000 radiosurgically treated intracranial AVM cases to delineate the incidence and management of this rare entity.

开云体育世界杯赔率

Between 1988 and 2019, 1010 patients with intracranial AVM underwent Gamma Knife SRS at the University of Pittsburgh Medical Center. In addition to a review of a prospective institutional database, the authors performed a retrospective chart review of the departmental AVM database to specifically identify patients with CEEH. Pertinent clinical and radiological characteristics as well as patient outcomes were recorded and analyzed.

RESULTS

Nine hundred fifty patients with intracranial AVM (94%) had sufficient clinical follow-up for analysis. Of these, 6 patients with CEEH underwent delayed resection (incidence rate of 0.0045 event per person-year). These patients included 4 males and 2 females with a mean age of 45.3 ± 13.8 years at the time of initial SRS. Four patients had smaller AVM volumes (4.9–10 cm3), and 3 of them were treated with a single SRS procedure. Two patients had larger-volume AVMs (55 and 56 cm3), and both underwent multimodal management that included staged SRS and embolization. Time to initial recognition of the CEEH after initial SRS ranged between 66 and 243 months. The time between CEEH recognition and resection ranged from 2 to 9 months. Resection was required because of progressive neurological symptoms that correlated with imaging evidence of gradual hematoma expansion. All 6 patients had angiographically confirmed obliteration of their AVM. Pathology revealed a mixed chronicity hematoma with areas of fibrosed blood vessels and rare areas of neovascularization with immature blood vessels but no evidence of a persistent AVM. All 6 patients reported persistent clinical improvement after hematoma resection.

CONCLUSIONS

CEEH after SRS for AVM is a rare complication with an incidence rate of 0.0045 event per person-year over the authors’ 30-year experience. When clinical symptoms progress and imaging reveals progressive enlargement over time, complete resection of a CEEH results in significant clinical recovery. Knowledge of this rare entity facilitates timely detection and eventual surgical intervention to achieve optimal outcomes.

InJournal of Neurosurgery Volume 136: Issue 2 (Feb 2022)

Free access

In vivo efficacy of decitabine as a natural killer cell–mediated immunotherapy against isocitrate dehydrogenase mutant gliomas

Xiaoran Zhang, Wi Jin Kim, Aparna V. Rao, Emade Jaman, Christopher P. Deibert, Poorva Sandlesh, Katharine Krueger, Jordan C. Allen, and Nduka M. Amankulor

OBJECTIVE

异柠檬酸脱氢酶(IDH)突变被发现in more than 80% of low-grade gliomas and in the majority of secondary glioblastomas. IDH mutation (IDHmut) leads to aberrant production of an oncogenic metabolite that promotes epigenetic dysregulation by inducing hypermethylation to suppress transcription of various tumor suppressor genes. Hypermethylation in IDHmut gliomas leads to transcriptional repression of NKG2D ligands, especially UL16-binding protein (ULBP)–1 and ULBP-3, and subsequent evasion of natural killer (NK) cell–mediated lysis. The demethylating agent 5-aza-2′deoxycytodine (decitabine [DAC]) is a DNA methyltransferase 1 inhibitor that prevents hypermethylation and is capable of restoring NKG2D ligand expression in IDHmut gliomas to resensitize them to NK cells. Given its capacity for sustained epigenetic reprogramming, the authors hypothesized that DCA would be an effective immunotherapeutic agent in treating IDHmut gliomas in an NK cell–dependent manner by upregulating epigenetically repressed activating NKG2D ligands in IDHmut tumors. In this study, the authors sought to use a glioma stem cell, preclinical animal model to determine the efficacy of DAC in IDHmut and IDH wild-type (IDHwt) tumors, and to characterize whether the activity of DAC in gliomas is dependent on NK cell function.

开云体育世界杯赔率

Xenograft models of IDHwt and IDHmut gliomas were established in athymic-nude mice. When tumors were grossly visible and palpable, mice were treated with either DCA or dimethylsulfoxide intraperitoneally every 7 days. Tumor sizes were measured every 2 to 3 days. After the animals were euthanized, xenografts were harvested and analyzed for the following: tumor expression of NKG2D ligands, tumor susceptibility to human and murine NK cells, immunohistochemistry for NK infiltration, and tumor-infiltrating lymphocyte characterization.

RESULTS

DAC significantly inhibited the growth of IDHmut xenografts in the athymic nude mice. This effect was abrogated with NK cell depletion. Ex vivo analysis of tumor cells from harvested xenografts confirmed that DAC increased NKG2D ligand ULBP-1 and ULBP-3 expressions, and enhanced susceptibility to lysis of both human and murine IDHmut glial cells with corresponding NK cells. Immunohistochemical analysis of the xenografts indicated that DCA-treated IDHmut gliomas had a greater level of NK infiltration into the tumor compared with the negative control. Finally, DCA radically altered the tumor-infiltrating lymphocyte landscape of IDHmut glioma xenografts by increasing NK cells, dendritic cells, and M1 macrophages, while decreasing suppressive monocyte infiltration.

CONCLUSIONS

DCA displayed novel immunotherapeutic functions in IDHmut gliomas. This effect was critically dependent on NK cells. Additionally, DCA significantly altered the tumor immune landscape in IDHmut gliomas from suppressive to proinflammatory.

InNeurosurgical Focus Volume 52 (2022): Issue 2 (Feb 2022): Update on Neuroimmunology

Open access

Combined exploratory laparotomy, transpsoas, and thoracic approach to resection of a giant spinal ganglioneuroma: illustrative case

Hansen Deng, Ahmed Habib, Edward G. Andrews, Xiaoran Zhang, David J. McCarthy, Zhishuo Wei, Rajeev Dhupar, M. Haroon Choudry, and Pascal O. Zinn

BACKGROUND

Ganglioneuromas are rare peripheral nervous system tumors of neural crest origin. Most are often asymptomatic and incidentally found, but large tumors can cause mass effect. Herein, the authors report a case of a giant ganglioneuroma that arose from the lumbar foramina into the retroperitoneal and thoracic cavities.

OBSERVATIONS

A 62-year-old female presented with low back pain, left lower extremity swelling, and increased sensation of an abdominal mass. Surgical treatment options were reviewed with the patient and coordinated care was planned by surgical oncological specialists. The patient opted for multistage exploratory laparotomy for abdominal mobilization, diaphragm resection, and en bloc resection with neuromonitoring. After surgery, the patient experienced significant improvement in symptoms.

LESSONS

A combined surgical exposure involving gastrointestinal, thoracic, and neurological surgeons can be important in the safe resection of ganglioneuromas that span multiple body cavities. Hence, a thorough preoperative assessment could help plan surgery accordingly.

InJournal of Neurosurgery: Case Lessons Volume 5 (2023): Issue 2 (Jan 2023)

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