Blister aneurysms are rare cerebrovascular lesions for which the treatment methods are reviewed here, with a focus on endovascular options. The reported pathogenesis of blister aneurysms varies, and hemodynamic stress, arterial dissection, and arteriosclerotic ulceration have all been described. There is consensus on the excessive fragility of blister aneurysms and their parent vessels, which makes clipping technically difficult. Open surgical treatment is associated with high rates of complications, morbidity, and mortality; endovascular treatment is a promising alternative. Among endovascular treatment options, deconstructive treatment has been associated with higher morbidity compared with reconstructive methods such as direct embolization, stent- or balloon-assisted direct embolization, stent monotherapy, and flow diversion. Flow diversion has been associated with higher technical success rates and similar clinical outcomes compared with non–flow diverting treatment methods. However, delayed aneurysm occlusion and the need for antiplatelet therapy are potential drawbacks to flow diversion that must be considered when choosing among treatment methods for blister aneurysms.
Geoffrey W. Peitz, Christopher A. Sy and Ramesh Grandhi
Sandi Lam, Ramesh Grandhi and Stephanie Greene
Meconium staining of open myelomeningoceles has been reported to occur both prenatally and postnatally, but meconium staining of the brainstem has not been previously documented. The authors present a case of meconium staining of the brainstem in an infant with a meconium-stained myelomeningocele, Chiari malformation Type II, and hydrocephalus and discuss possible implications for prenatal and perinatal care.
Mariam Ishaque, David J. Wallace and Ramesh Grandhi
Throughout history, neurosurgical procedures have been fundamental in advancing neuroscience; however, this has not always been without deleterious side effects or harmful consequences. While critical to the progression of clinical neuroscience during the early 20th century, yet, at the same time, poorly tolerated by patients, pneumoencephalography is one such procedure that exemplifies this juxtaposition. Presented herein are historical perspectives and reflections on the role of the pneumoencephalography in the diagnosis and treatment of neuropsychiatric illnesses.
Silvia Gesheva, William T. Couldwell, Vance Mortimer, Philipp Taussky and Ramesh Grandhi
Dural arteriovenous fistulae (dAVFs) are vascular anomalies formed by abnormal connections between branches of dural arteries and dural veins or dural venous sinus(es). These pathologic shunts constitute 10%–15% of all intracranial arteriovenous malformations. The hallmark of malignant dAVFs is the presence of cortical venous drainage, a finding that increases the likelihood of nonhemorrhagic neurologic deficit, intracranial hemorrhage, and mortality if left unaddressed. Endovascular approaches have become the primary modality for the treatment of dAVFs. The authors present a case of staged endovascular transarterial embolization of a malignant dAVF running parallel to the left transverse sinus in a patient with headaches and pulsatile tinnitus. The fistula was completely treated using Onyx and n-butyl cyanoacrylate.
The video can be found here: https://youtu.be/GSAto_wlC3I.
Srinivas Chivukula, Ramesh Grandhi and Robert M. Friedlander
Two key discoveries in the 19th century—infection control and the development of general anesthesia—provided an impetus for the rapid advancement of surgery, especially within the field of neurosurgery. Improvements in anesthesia and perioperative care, in particular, fostered the development of meticulous surgical technique conducive to the refinement of neuroanatomical understanding and optimization of neurosurgical procedures and outcomes. Yet, even dating back to the earliest times, some form of anesthesia or perioperative pain management was used during neurosurgical procedures. Despite a few reports on anesthesia published around the time of William Morton's now-famous public demonstration of ether anesthesia in 1846, relatively little is known or written of early anesthetics in neurosurgery. In the present article the authors discuss the history of anesthesia pertaining to neurosurgical procedures and draw parallels between the refinements and developments in anesthesia care over time with some of the concomitant advances in neurosurgery.
Samon Tavakoli, Geoffrey Peitz, William Ares, Shaheryar Hafeez and Ramesh Grandhi
Intracranial pressure monitoring devices have become the standard of care for the management of patients with pathologies associated with intracranial hypertension. Given the importance of invasive intracranial monitoring devices in the modern neurointensive care setting, gaining a thorough understanding of the potential complications related to device placement—and misplacement—is crucial. The increased prevalence of intracranial pressure monitoring as a management tool for neurosurgical patients has led to the publication of a plethora of papers regarding their indications and complications. The authors aim to provide a concise review of key contemporary articles in the literature concerning important complications with the hope of elucidating practices that improve outcomes for neurocritically ill patients.
Michael Karsy, Philipp Taussky and Ramesh Grandhi
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.
David J. Wallace, Naomi L. Sayre, T. Tyler Patterson, Susannah E. Nicholson, Donald Hilton and Ramesh Grandhi
In addition to standard management for the treatment of the acute phase of spinal cord injury (SCI), implementation of novel neuroprotective interventions offers the potential for significant reductions in morbidity and long-term health costs. A better understanding of the systemic changes after SCI could provide insight into mechanisms that lead to secondary injury. An emerging area of research involves the complex interplay of the gut microbiome and the CNS, i.e., a brain–gut axis, or perhaps more appropriately, a CNS–gut axis. This review summarizes the relevant literature relating to the gut microbiome and SCI. Experimental models in stroke and traumatic brain injury demonstrate the bidirectional communication of the CNS to the gut with postinjury dysbiosis, gastrointestinal-associated lymphoid tissue–mediated neuroinflammatory responses, and bacterial-metabolite neurotransmission. Similar findings are being elucidated in SCI as well. Experimental interventions in these areas have shown promise in improving functional outcomes in animal models. This commensal relationship between the human body and its microbiome, particularly the gut microbiome, represents an exciting frontier in experimental medicine.
Christopher M. Bonfield, Lesley M. Foley, Shinjini Kundu, Wendy Fellows-Mayle, T. Kevin Hitchens, Gustavo K. Rohde, Ramesh Grandhi and Mark P. Mooney
Craniosynostosis is a condition in which one or more of the calvarial sutures fuses prematurely. In addition to the cosmetic ramifications attributable to premature suture fusion, aberrations in neurophysiological parameters are seen, which may result in more significant damage. This work examines the microstructural integrity of white matter, using diffusion tensor imaging (DTI) in a homogeneous strain of rabbits with simple, familial coronal suture synostosis before and after surgical correction.
After diagnosis, rabbits were assigned to different groups: wild-type (WT), rabbits with early-onset complete fusion of the coronal suture (BC), and rabbits that had undergone surgical correction with suturectomy (BC-SU) at 10 days of age. Fixed rabbit heads were imaged at 12, 25, or 42 days of life using a 4.7-T, 40-cm bore Avance scanner with a 7.2-cm radiofrequency coil. For DTI, a 3D spin echo sequence was used with a diffusion gradient (b = 2000 sec/mm2) applied in 6 directions.
As age increased from 12 to 42 days, the DTI differences between WT and BC groups became more pronounced (p < 0.05, 1-way ANOVA), especially in the corpus callosum, cingulum, and fimbriae. Suturectomy resulted in rabbits with no significant differences compared with WT animals, as assessed by DTI of white matter tracts. Also, it was possible to predict to which group an animal belonged (WT, BC, and BC-SU) with high accuracy based on imaging data alone using a linear support vector machine classifier. The ability to predict to which group the animal belonged improved as the age of the animal increased (71% accurate at 12 days and 100% accurate at 42 days).
Craniosynostosis results in characteristic changes of major white matter tracts, with differences becoming more apparent as the age of the rabbits increases. Early suturectomy (at 10 days of life) appears to mitigate these differences.