Charles G. Kulwin, Ravi H. Gandhi, Neal B. Patel and Troy D. Payner
Neal B. Patel, Courtney Pendleton, Alfredo Quiñones-Hinojosa and Aaron A. Cohen-Gadol
The discipline of neurological surgery was considered primarily “hopeless” and, at best, experimental in the late 19th century. Harvey Cushing's efforts during his initial uncharted voyage through the surgery of the human cranium were rudimentary and exploratory. A direct review of his available patient records from early in his career provides the opportunity to look back at Cushing as a physician-scientist, uncovering work that demonstrates that he was at the forefront of neurosurgical intervention in avenues that have been largely overlooked. The authors present Cushing's notes pertaining to a case of tetanus. This case represents the intersection of neurosurgery and tetanus treatment in Dr. Cushing's intracerebral injection of antitoxin to treat generalized tetanus.
R. Shane Tubbs, Neal Patel, Brian Vala Nahed, Aaron A. Cohen-Gadol and Robert J. Spinner
By the time Harvey Cushing entered medical school, nerve reconstruction techniques had been developed, but peripheral nerve surgery was still in its infancy. As an assistant surgical resident influenced by Dr. William Halsted, Cushing wrote a series of reports on the use of cocaine for nerve blocks. Following his residency training and a hiatus to further his clinical interests and intellectual curiosity, he traveled to Europe and met with a variety of surgeons, physiologists, and scientists, who likely laid the groundwork for Cushing's increased interest in peripheral nerve surgery. Returning to The Johns Hopkins Hospital in 1901, he began documenting these surgeries. Patient records preserved at Yale's Cushing Brain Tumor Registry describe Cushing's repair of ulnar and radial nerves, as well as his exploration of the brachial plexus for nerve repair or reconstruction. The authors reviewed Harvey Cushing's cases and provide 3 case illustrations not previously reported by Cushing involving neurolysis, nerve repair, and neurotization. Additionally, Cushing's experience with facial nerve neurotization is reviewed. The history, physical examination, and operative notes shed light on Cushing's diagnosis, strategy, technique, and hence, his surgery on peripheral nerve injury. These contributions complement others he made to surgery of the peripheral nervous system dealing with nerve pain, entrapment, and tumor.
Neal B. Patel, Matthew A. Hazzard, Laurie L. Ackerman and Eric M. Horn
Unstable pediatric cervical spine injuries present significant challenges in terms of fixation. Given the smaller cervical vertebral bodies in the preschool-aged population, commercially available pediatric cervical fixation instrumentation may be unsuitable because of the inappropriately large size of the screws and plates. The authors describe a 2-year-old girl who sustained an unstable C6–7 distraction injury during a motor vehicle accident. Because of the small size of her vertebral bodies, standard cervical spine instrumentation was not feasible, and posterior wiring alone was believed to be insufficient because of the complete distraction of all 3 spinal columns. The patient was taken to the operating room where craniofacial plates with an inherent locking mechanism were used to circumferentially stabilize the cervical spine. Follow-up examination 6 months postoperatively demonstrated stable cervical spine alignment and fusion with no evidence of the failure of either the anterior or posterior hardware. The use of craniofacial miniplates with an intrinsic locking mechanism represents a superior alternative for both anterior and posterior cervical fixations when spinal instrumentation is needed in the pediatric age group.
Daniel H. Fulkerson, Shobhan Vachhrajani, Bradley N. Bohnstedt, Neal B. Patel, Akash J. Patel, Benjamin D. Fox, Andrew Jea and Joel C. Boaz
Premature, low-birth-weight infants with posthemorrhagic hydrocephalus have a high risk of shunt obstruction and infection. Established risk factors for shunt failure include grade of the hemorrhage and age at shunt insertion. There is anecdotal evidence that the amount of red blood cells or protein levels in the CSF may affect shunt performance. However, this has not been analyzed specifically for this cohort of high-risk patients. Therefore, the authors performed this study to examine whether any statistical relationship exists between the CSF constituents and the rate of shunt malfunction or infection in this population.
A retrospective cohort study was performed on premature infants born at Riley Hospital for Children from 2000 to 2009. Inclusion criteria were a CSF sample analyzed within 2 weeks prior to shunt insertion, low birth weight (< 1500 grams), prematurity (birth prior to 37 weeks estimated gestational age), and shunt insertion for posthemorrhagic hydrocephalus. Data points included the gestational age at birth and shunt insertion, weight at birth and shunt insertion, history of CNS infection prior to shunt insertion, shunt failure, shunt infection, and the levels of red blood cells, white blood cells, protein, and glucose in the CSF. Statistical analysis was performed to determine any association between shunt outcome and the CSF parameters.
Fifty-eight patients met the study entry criteria. Ten patients (17.2%) had primary shunt failure within 3 months of insertion. Nine patients (15.5%) had shunt infection within 3 months. A previous CNS infection prior to shunt insertion was a statistical risk factor for shunt failure (p = 0.0290) but not for shunt infection. There was no statistical relationship between shunt malfunction or infection and the CSF levels of red blood cells, white blood cells, protein, or glucose before shunt insertion.
Low-birth-weight premature infants with posthemorrhagic hydrocephalus have a high rate of shunt failure and infection. The authors did not find any association of shunt failure or infection with CSF cell count, protein level, or glucose level. Therefore, it may not be useful to base the timing of shunt insertion on CSF parameters.
Charles G. Kulwin, Neal B. Patel, Laurie L. Ackerman, Jodi L. Smith, Joel C. Boaz and Daniel H. Fulkerson
The surgical management of patients with symptoms of tethered cord syndrome (TCS) who lack significant radiographic abnormalities is controversial. One potential MRI marker for TCS is a spinal cord syrinx or syringomyelia. Alternatively, a syrinx may be a benign and incidental finding. In this report the authors evaluated a highly selected cohort of patients with symptoms of TCS with minimal radiographic abnormalities other than syringomyelia. They analyzed clinical and radiographic outcomes after tethered cord release (TCR).
A retrospective review of data from 16 children who met the study inclusion criteria was performed. All patients had been surgically treated at Riley Hospital for Children in Indianapolis, Indiana, between 2006 and 2011. All children had clinical symptoms of TCS as well as available pre- and postoperative MRI data.
The most common presentation (12 [75%] of 16 patients) was urinary dysfunction, defined as symptoms of urgency or incontinence with abnormal urodynamic studies. Clinical follow-up data were available in 11 of these 12 patients. All 11 had improvement in symptoms at an average follow-up of 17 months. Seven (87.5%) of 8 patients presenting with back or leg pain had improvement. Three patients had progressive scoliosis; 2 had stabilization of the curve or mild improvement, and 1 patient had worsening deformity.
Radiographic follow-up data were obtained an average of 14.5 months after surgery. Twelve patients (75%) had stable syringomyelia after TCR. Four patients showed improvement, with 2 having complete radiographic resolution.
Highly selected patients with symptoms of TCS did very well clinically. Patients with abnormal urodynamic studies, pain, and gait disturbances showed a high rate of symptomatic improvement. However, a smaller percentage of patients had radiographic improvement of the syrinx. Therefore, the authors suggest that the decision to perform TCR should be based on clinical symptoms in this population. Symptomatic improvement was not necessarily related to radiographic resolution of the syrinx.
John C. Drummond and Piyush M. Patel
Daniel H. Fulkerson, Todd D. Vogel, Abdul A. Baker, Neal B. Patel, Laurie L. Ackerman, Jodi L. Smith and Joel C. Boaz
The optimal treatment of symptomatic posterior fossa arachnoid cysts is controversial. Current options include open or endoscopic resection, fenestration, or cyst-peritoneal shunt placement. There are potential drawbacks with all options. Previous authors have described stenting a cyst into the ventricular system for supratentorial lesions. The current authors have used a similar strategy for posterior fossa cysts.
The authors performed a retrospective review of 79 consecutive patients (1993–2010) with surgically treated intracranial arachnoid cysts.
The authors identified 3 patients who underwent placement of a stent from a posterior fossa arachnoid cyst to a supratentorial ventricle. In 2 patients the stent construct consisted of a catheter placed into a posterior fossa arachnoid cyst and connecting to a lateral ventricle catheter. Both patients underwent stent placement as a salvage procedure after failure of open surgical fenestration. In the third patient a single-catheter cyst-ventricle stent was stereotactically placed. All 3 patients improved clinically. Two patients remained asymptomatic, with radiographic stability in a follow-up period of 1 and 5 years, respectively. The third patient experienced initial symptom resolution with a demonstrable reduction of intracystic pressure. However, he developed recurrent headaches after 2 years.
Posterior fossa cyst–ventricle stenting offers the benefits of ease of surgical technique and a low morbidity rate. It may also potentially reduce the incidence of shunt-related headaches by equalizing the pressure between the posterior fossa and the supratentorial compartments. While fenestration is considered the first-line therapy for most symptomatic arachnoid cysts, the authors consider cyst-ventricle stenting to be a valuable additional strategy in treating these rare and often difficult lesions.
Zong-Fu Chen, Toshifumi Kamiryo, Scott L. Henson, Haruaki Yamamoto, Edward H. Bertram, Frank Schottler, Ferish Patel, Ladislau Steiner, Dheerendra Prasad, Neal F. Kassell, Shahrzad Shareghis and Kevin S. Lee
Object. The management of intractable epilepsy remains a challenge, despite advances in its surgical and nonsurgical treatment. The identification of low-risk, low-cost therapeutic strategies that lead to improved outcome is therefore an important ongoing goal of basic and clinical research. Single-dose focal ionizing beam radiation delivered at necrosis- inducing and subnecrotic levels was investigated for its effects on seizure activity by using an established model of chronic recurrent spontaneous limbic seizures in rats.
Methods. A single 90-minute period of repetitive electrical stimulation (inducing stimulus) of the hippocampus in rats elicited a single episode of status epilepticus, followed by a 2- to 4-week seizure-free period. Spontaneous recurrent seizures developed subsequently and persisted for the duration of monitoring (2–10 months). Simultaneous computerized electroencephalography and video recording were used to monitor the animals. After the establishment of spontaneous recurrent seizures, bilateral radiation centered in the ventral hippocampal formation was administered with the Leksell gamma knife, aided by a stereotactic device custom made for small animals. A center dose of 10, 20, or 40 Gy was administered using a 4-mm collimator. Control animals were subjected to the same seizure-inducing stimulus but underwent a sham treatment instead of gamma irradiation.
In a second experiment, the authors examined the effects of gamma irradiation on the proclivity of hippocampal neurons to display epileptiform discharges. Naive animals were irradiated with a single 40-Gy dose, as already described. Slices of the hippocampus were prepared from animals killed between 1 and 178 days postirradiation. Sensitivity to penicillin-induced epileptiform spiking was examined in vitro in slices prepared from control and irradiated rat brains.
Conclusions. In the first experiment, single doses of 20 or 40 Gy (but not 10 Gy) reduced substantially, and in some cases eliminated, behaviorally and electrographically recognized seizures. Significant reductions in both the frequency and duration of spontaneous seizures were observed during a follow-up period of up to 10 months postradiation. Histological examination of the targeted region did not reveal signs of necrosis. These findings indicate that single-dose focal ionizing beam irradiation at subnecrotic dosages reduces or eliminates repetitive spontaneous seizures in a rat model of temporal lobe epilepsy. In the second experiment, synaptically driven neuronal firing was shown to be intact in hippocampal neurons subjected to 40-Gy doses. However, the susceptibility to penicillin-induced epileptiform activity was reduced in the brain slices of animals receiving 40-Gy doses, compared with those from control rats that were not irradiated. The results provide rational support for the utility of subnecrotic gamma irradiation as a therapeutic strategy for treating epilepsy. These findings also provide evidence that a functional increase in the seizure threshold of hippocampal neurons contributes to the anticonvulsant influence of subnecrotic gamma irradiation.
Ashish H. Shah, Neal Patel, Daniel M. S. Raper, Amade Bregy, Ramsey Ashour, Mohamed Samy Elhammady, Mohammad Ali Aziz-Sultan, Jacques J. Morcos, Roberto C. Heros and Ricardo J. Komotar
As endovascular techniques have become more advanced, preoperative embolization has become an increasingly used intervention in the management of meningiomas. To date, however, no consensus has been reached on the use of this technique. To clarify the role of preoperative embolization in the management of meningiomas, the authors conducted a systematic review of case reports, case series, and prospective studies to increase the current understanding of the management options for these common lesions and complications associated with preoperative embolization.
A PubMed search was performed to include all relevant studies in which the management of intracranial meningiomas with preoperative embolization was reported. Immediate complications of embolization were reported as major (sustained) or minor (transient) deficits, death, or no neurological deficits.
A total of 36 studies comprising 459 patients were included in the review. Among patients receiving preoperative embolization for meningiomas, 4.6% (n = 21) sustained complications as a direct result of embolization. Of the 21 patients with embolization-induced complications, the incidence of major complications was 4.8% (n = 1) and the mortality rate was 9.5% (n = 2).
Preoperative embolization is associated with an added risk for morbidity and mortality. Preoperative embolization may be associated with significant complications, but careful selection of ideal cases for embolization may help reduce any added morbidity with this procedure. Although not analyzed in the authors' study, embolization may still reduce rates of surgical morbidity and mortality and therefore may still have a potential benefit for selected patients. Future prospective studies involving the use of preoperative embolization in certain cases of meningiomas may further elucidate its potential benefit and risks.