Modern cortical mapping is a cornerstone for safe supratentorial glioma resection in eloquent brain and allows maximal resection with improved functional outcomes. The unlocking of brain functionality through close observation and eventually via cortical stimulation has a fascinating history and was made possible by contributions from early physician-philosophers and neurosurgery’s founding fathers. Without an understanding of brain function and functional localization, none of today’s modern cortical mapping would be possible.
Zach Folzenlogen and D. Ryan Ormond
D. Ryan Ormond and Costas G. Hadjipanayis
The history of neurosurgery is filled with descriptions of brave surgeons performing surgery against great odds in an attempt to improve outcomes in their patients. In the distant past, most neurosurgical procedures were limited to trephination, and this was sometimes performed for unclear reasons. Beginning in the Renaissance and accelerating through the middle and late 19th century, a greater understanding of cerebral localization, antisepsis, anesthesia, and hemostasis led to an era of great expansion in neurosurgical approaches and techniques. During this process, frontotemporal approaches were also developed and refined over time. Progress often depended on the technical advances of scientists coupled with the innovative ideas and courage of pioneering surgeons. A better understanding of this history provides insight into where we originated as a specialty and in what directions we may go in the future. This review considers the historical events enabling the development of neurosurgery as a specialty, and how this relates to the development of frontotemporal approaches.
D. Ryan Ormond, Joseph Kahamba, Kevin O. Lillehei and Nicephorus Rutabasibwa
Tanzania sits on the Indian Ocean in East Africa and has a population of over 53 million people. While the gross domestic product has been increasing in recent years, distribution of wealth remains a problem, and challenges in the distribution of health services abound. Neurosurgery is a unique case study of this problem. The challenges facing the development of neurosurgery in Tanzania are many and varied, built largely out of the special needs of modern neurosurgery. Task shifting (training nonphysician surgical providers) and 2-tiered systems (fast-track certification of general surgeons to perform basic neurosurgical procedures) may serve some of the immediate need, but these options will not sustain the development of a comprehensive neurosurgical footprint. Ultimately, long-term solutions to the need for neurosurgical care in Tanzania can only be fulfilled by local government investment in capacity building (infrastructure and neurosurgical training), and the commitment of Tanzanians trained in neurosurgery. With this task in mind, Tanzania developed an independent neurosurgery training program in Dar es Salaam. While significant progress has been made, a number of training deficiencies remain. To address these deficiencies, the Muhimbili Orthopedic Institute (MOI) Division of Neurosurgery and the University of Colorado School of Medicine Department of Neurosurgery set up a Memorandum of Understanding in 2016. This relationship was developed with the perspective of a “collaboration of equals.” Through this collaboration, faculty members and trainees from both institutions have the opportunity to participate in international exchange, join in collaborative research, experience the culture and friendship of a new country, and share scholarship through presentations and teaching. Ultimately, through this international partnership, mutual improvement in the care of the neurosurgical patient will develop, bringing programs like MOI out of isolation and obscurity. From Dar es Salaam, a center of excellence is developing to train neurosurgeons who can go well equipped throughout Tanzania to improve the care of the neurosurgical patient everywhere. The authors encourage further such exchanges to be developed between partnership training programs throughout the world, improving the scholarship, subspecialization, and teaching expertise of partner programs throughout the world.
D. Ryan Ormond, Hong Peng, Richard Zeman, Kaushik Das, Raj Murali and Meena Jhanwar-Uniyal
Spinal cord injury (SCI) is a debilitating disease. Primary SCI results from direct injury to the spinal cord, whereas secondary injury is a side effect from subsequent edema and ischemia followed by activation of proinflammatory cytokines. These cytokines activate the prosurvival molecule nuclear factor–κB and generate obstacles in spinal cord reinnervation due to gliosis. Curcumin longa is an active compound found in turmeric, which acts as an antiinflammatory agent primarily by inhibiting nuclear factor–κB. Here, the authors study the effect of curcumin on SCI recovery.
Fourteen female Sprague-Dawley rats underwent T9–10 laminectomy and spinal cord contusion using a weight-drop apparatus. Within 30 minutes after contusion and weekly thereafter, curcumin (60 mg/kg/ml body weight in dimethyl sulfoxide) or dimethyl sulfoxide (1 ml/kg body weight) was administered via percutaneous epidural injection at the injury site. Spinal cord injury recovery was assessed weekly by scoring hindlimb motor function. Animals were killed 6 weeks postcontusion for histopathological analysis of spinal cords and soleus muscle weight evaluation.
Curcumin-treated rats had improved motor function compared with controls starting from Week 1. Body weight gain significantly improved, correlating with improved Basso-Beattie-Bresnahan scores. Soleus muscle weight was greater in curcumin-treated rats than controls. Histopathological analysis validated these results with increased neural element mass with less gliosis at the contusion site in curcumin-treated rats than controls.
Epidural administration of curcumin resulted in improved recovery from SCI. This occurred with no adverse effects noted in experimental animals. Therefore, curcumin treatment may translate into a novel therapy for humans with SCI.
D. Ryan Ormond, Ibrahim Omeis, Avinash Mohan, Raj Murali and Prithvi Narayan
✓ Cysts occupying the third ventricle are rare lesions and may appear as an unusual cause of obstructive hydrocephalus. Various types of lesions occur in this location, and they generally have an arachnoidal, endodermal, or neuroepithelial origin. The authors present a case of acute hydrocephalus following minor trauma in a child due to cerebrospinal fluid outflow obstruction by a third ventricular cyst. Definitive diagnosis of this cystic lesion was possible only with contrast ventriculography and not routine computed tomography or magnetic resonance imaging. The investigation, treatment, and pathological findings are discussed.
Michael Karsy, Mohammed A. Azab, Hussam Abou-Al-Shaar, Jian Guan, Ilyas Eli, Randy L. Jensen and D. Ryan Ormond
Meningiomas are among the most common intracranial pathological conditions, accounting for 36% of intracranial lesions treated by neurosurgeons. Although the majority of these lesions are benign, the classical categorization of tumors by histological type or World Health Organization (WHO) grade has not fully captured the potential for meningioma progression and recurrence. Many targeted treatments have failed to generate a long-lasting effect on these tumors. Recently, several seminal studies evaluating the genomics of intracranial meningiomas have rapidly changed the understanding of the disease. The importance of NF2 (neurofibromin 2), TRAF7 (tumor necrosis factor [TNF] receptor–associated factor 7), KLF4 (Kruppel-like factor 4), AKT1, SMO (smoothened), PIK3CA (phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha), and POLR2 (RNA polymerase II subunit A) demonstrates that there are at least 6 distinct mutational classes of meningiomas. In addition, 6 methylation classes of meningioma have been appreciated, enabling improved prediction of prognosis compared with traditional WHO grades. Genomic studies have shed light on the nature of recurrent meningioma, distinct intracranial locations and mutational patterns, and a potential embryonic cancer stem cell–like origin. However, despite these exciting findings, the clinical relevance of these findings remains elusive. The authors review the key findings from recent genomic studies in meningiomas, specifically focusing on how these findings relate to clinical insights for the practicing neurosurgeon.
Soliman Oushy, Stefan H. Sillau, Douglas E. Ney, Denise M. Damek, A. Samy Youssef, Kevin O. Lillehei and D. Ryan Ormond
Prophylactic use of antiepileptic drugs (AEDs) in seizure-naïve brain tumor patients remains a topic of debate. This study aimed to characterize a subset of patients at highest risk for new-onset perioperative seizures (i.e., intraoperative and postoperative seizures occurring within 30 days of surgery) who may benefit from prophylactic AEDs.
The authors conducted a retrospective case-control study of all adults who had undergone tumor resection or biopsy at the authors’ institution between January 1, 2004, and June 31, 2015. All patients with a history of preoperative seizures, posterior fossa tumors, pituitary tumors, and parasellar tumors were excluded. A control group was matched to the seizure patients according to age (± 0 years). Demographic data, clinical status, operative data, and postoperative course data were collected and analyzed.
Among 1693 patients who underwent tumor resection or biopsy, 549 (32.4%) had never had a preoperative seizure. Of these 549 patients, 25 (4.6%) suffered a perioperative seizure (Group 1). A total of 524 patients (95.4%) who remained seizure free were matched to Group 1 according to age (± 0 years), resulting in 132 control patients (Group 2), at an approximate ratio of 1:5. There were no differences between the patient groups in terms of age, sex, race, relationship status, and neurological deficits on presentation. Histological subtype (infiltrating glioma vs meningioma vs other, p = 0.041), intradural tumor location (p < 0.001), intraoperative cortical stimulation (p = 0.004), and extent of resection (less than gross total, p = 0.002) were associated with the occurrence of perioperative seizures.
While most seizure-naïve brain tumor patients do not benefit from perioperative seizure prophylaxis, such treatment should be considered in high-risk patients with supratentorial intradural tumors, in patients undergoing intraoperative cortical stimulation, and in patients in whom subtotal resection is likely.