Nonhemorrhagic neurological deficits are underrecognized symptoms of intracranial dural arteriovenous fistulas (dAVFs) having cortical venous drainage. These symptoms are the consequence of cortical venous hypertension and portend a clinical course with increased risk of neurological morbidity and mortality. One rarely documented and easily misinterpreted type of nonhemorrhagic neurological deficit is progressive dementia, which can result from venous hypertension in the cortex or in bilateral thalami. The latter, which is due to dAVF drainage into the deep venous system, is the less common of these 2 dementia syndromes. Herein, the authors report 4 cases of dAVF with venous drainage into the vein of Galen causing bithalamic edema and rapidly progressive dementia. Two patients were treated successfully with endovascular embolization, and the other 2 patients were treated successfully with endovascular embolization followed by surgery. The radiographic abnormalities and presenting symptoms rapidly resolved after dAVF obliteration in all 4 cases. Detailed descriptions of these 4 cases are presented along with a critical review of 15 previously reported cases. In our analysis of these 19 published cases, the following were emphasized: 1) the clinical and radiographic differences between dAVF-induced thalamic versus cortical dementia syndromes; 2) the differential diagnosis and necessary radiographic workup for patients presenting with a rapidly progressive thalamic dementia syndrome; 3) the frequency at which delays in diagnosis occurred and potentially dangerous and avoidable diagnostic procedures were used; and 4) the rapidity and completeness of symptom resolution following dAVF treatment.
Terrence F. Holekamp, Matthew E. Mollman, Rory K. J. Murphy, Grant R. Kolar, Neha M. Kramer, Colin P. Derdeyn, Christopher J. Moran, Richard J. Perrin, Keith M. Rich, Giuseppe Lanzino and Gregory J. Zipfel
Sudhakar Vadivelu, Marina M. Platik, Luke Choi, Molly L. Lacy, Aarti R. Shah, Yun Qu, Terrence F. Holekamp, Daniel Becker, David I. Gottlieb, Jeffrey M. Gidday and John W. McDonald
To restore proper function to a damaged central nervous system (CNS) through transplantation, it is necessary to replace both neural and nonneural elements that arise from different germ layers in the embryo. Mounting evidence indicates the importance of signals related to vasculogenesis in governing neural proliferation and differentiation in early CNS development. Here, the authors examined whether embryonic stem cell (ESC)—derived progenitors can selectively generate both neural and endothelial cells after transplantation in the damaged CNS.
Injections of 20 nmol N-methyl-d-aspartate created a unilateral striatal injury in 7-day-old rats. One week postinjury, murine ESCs, neural-induced with retinoic acid, were transplanted into the injured striatum. Histological staining, laser confocal microscopy, and transmission electron microscopy of grafted ESCs were performed 1 week posttransplantation.
Transplanted ESCs differentiated into neural cells, which segregated into multiple pools and formed neurons that conformed to host cytoarchitecture. The ESCs also generated endothelial cells, which integrated with host cells to form chimeric vasculature. The combination of ESC pluripotentiality and multiple germ layer differentiation provides a new conceptual framework for CNS repair.
Jakub Godzik, Michael P. Kelly, Alireza Radmanesh, David Kim, Terrence F. Holekamp, Matthew D. Smyth, Lawrence G. Lenke, Joshua S. Shimony, Tae Sung Park, Jeffrey Leonard and David D. Limbrick
Chiari malformation Type I (CM-I) is a developmental abnormality often associated with a spinal syrinx. Patients with syringomyelia are known to have an increased risk of scoliosis, yet the influence of specific radiographically demonstrated features on the prevalence of scoliosis remains unclear. The primary objective of the present study was to investigate the relationship of maximum syrinx diameter and tonsillar descent to the presence of scoliosis in patients with CM-I–associated syringomyelia. A secondary objective was to explore the role of craniovertebral junction (CVJ) characteristics as additional risk factors for scoliosis.
The authors conducted a retrospective review of pediatric patients evaluated for CM-I with syringomyelia at a single institution in the period from 2000 to 2012. Syrinx morphology and CVJ parameters were evaluated with MRI, whereas the presence of scoliosis was determined using standard radiographic criteria. Multiple logistic regression was used to analyze radiological features that were independently associated with scoliosis.
Ninety-two patients with CM-I and syringomyelia were identified. The mean age was 10.5 ± 5 years. Thirty-five (38%) of 92 patients had spine deformity; 23 (66%) of these 35 patients were referred primarily for deformity, and 12 (34%) were diagnosed with deformity during workup for other symptoms. Multiple regression analysis revealed maximum syrinx diameter > 6 mm (OR 12.1, 95% CI 3.63–40.57, p < 0.001) and moderate (5–12 mm) rather than severe (> 12 mm) tonsillar herniation (OR 7.64, 95% CI 2.3–25.31, p = 0.001) as significant predictors of spine deformity when controlling for age, sex, and syrinx location.
The current study further elucidates the association between CM-I and spinal deformity by defining specific radiographic characteristics associated with the presence of scoliosis. Specifically, patients presenting with larger maximum syrinx diameters (> 6 mm) have an increased risk of scoliosis.