Sandeep Kandregula and Bharat Guthikonda
David E. Connor Jr., Menarvia Nixon, Anil Nanda, and Bharat Guthikonda
The authors conducted a study to evaluate the published results of vagal nerve stimulation (VNS) for medically refractory seizures according to evidence-based criteria.
The authors performed a review of available literature published between 1980 and 2010. Inclusion criteria for articles included more than 10 patients evaluated, average follow-up of 1 or more years, inclusion of medically refractory epilepsy, and consistent preoperative surgical evaluation. Articles were divided into 4 classes of evidence according to criteria established by the American Academy of Neurology.
A total of 70 publications were reviewed, of which 20 were selected for review based on inclusion and exclusion criteria. There were 2 articles that provided Class I evidence, 7 that met criteria for Class II evidence, and 11 that provided Class III evidence.
The majority of evidence supports VNS usage in partial epilepsy with a seizure reduction of 50% or more in the majority of cases and freedom from seizure in 6%–27% of patients who responded to stimulation. High stimulation with a gradual increase in VNS stimulation over the first 6 weeks to 3 months postoperatively is well supported by Class I and II data. Predictors of positive response included absence of bilateral interictal epileptiform activity and cortical malformations.
Vagal nerve stimulation is a safe and effective alternative for adult and pediatric populations with epilepsy refractory to medical and other surgical management.
Shyamal C. Bir, Subhas Konar, Tanmoy Maiti, Anil Nanda, and Bharat Guthikonda
Spinal cord stimulators (SCSs) appear to be safe and efficacious for chronic intractable back pain. Although there are many reports on percutaneous SCSs, there are very few studies on outcomes of paddle lead SCSs. In addition, the predictors of requirement for SCS revision have not been well established. Here, the authors review the outcome of a case series and attempt to identify the predictors of SCS revisions.
The clinical and radiological information of 141 patients with intractable chronic pain who underwent SCS implantation within the past 20 years was retrospectively reviewed. Paddle lead SCSs were used in this series. Statistical analysis was conducted using Kaplan-Meier curves and Cox proportional-hazards regression.
Among 141 cases, 90 (64%) did not require any revision after SCS implantations. Removal of the SCS was required in 14 patients. The average pain score was significantly reduced (preimplantation score of 8 vs postimplantation score of 1.38; p < 0.0001). Younger age, male sex, obesity, a preimplantation pain score ≥ 8, and the presence of neuromuscular pain were identified as predictors of the overall requirement for SCS revision. However, only a preimplantation pain score ≥ 8 was identified as a predictor of early failure of the SCS.
Implantation of a paddle lead SCS is a relatively less invasive, safe, and effective procedure for patients with intractable back pain. Revision of the procedure depends on many factors, including younger age, male sex, associated neuromuscular pain, and severity of the pain. Therefore, patients with these factors, for whom implantation of an SCS is planned, should be closely followed for the possible requirement for revision.
Imad Saeed Khan, Osama Ahmed, Jai Deep Thakur, Cedric D. Shorter, and Bharat Guthikonda
Klippel-Feil syndrome, or brevicollis, is a complex congenital disorder caused by the improper segmentation of the cervical vertebrae. The authors present the very rare case of a patient with Klippel-Feil syndrome who presented with an intradural arachnoid cyst at the craniocervical junction. They also examine possible factors contributing to this association.
A 46-year-old woman presented with complaints of progressively worsening headaches and dizziness of 18 months' duration. She also demonstrated mild bilateral upper-extremity weakness. Magnetic resonance imaging revealed fused cervical vertebrae and a dorsal intradural arachnoid cyst at the craniocervical junction, extending down to the fourth cervical level. Because of worsening myelopathy and the presence of brainstem compression, the patient underwent surgical excision of the arachnoid cyst, which was approached via a midline posterior suboccipital/upper cervical route. An endoscope was introduced through a gap between the occiput and fused upper cervical vertebrae, and the arachnoid cyst was widely fenestrated. Postoperatively, the patient has remained symptom free for more than 2 years with evidence of good radiological decompression.
The authors report a unique association between craniocervical arachnoid cyst and Klippel-Feil syndrome. To their knowledge, no other cases of this association have been reported in the literature. Arachnoid cysts should be part of the differential diagnosis in the presence of worsening myelopathic symptoms or pain in patients with Klippel-Feil syndrome.
Mayur Sharma, Sudheer Ambekar, Bharat Guthikonda, Jessica Wilden, and Anil Nanda
The aim of this study was to analyze the incidence of adverse outcomes, complications, inpatient mortality, length of hospital stay, and the factors affecting them between academic and nonacademic centers after deep brain stimulation (DBS) surgery for Parkinson's disease (PD). The authors also analyzed the impact of various factors on the total hospitalization charges after this procedure.
This is a retrospective cohort study using the Nationwide Inpatient Sample (NIS) from 2006 to 2010. Various patient and hospital variables were analyzed from the database. The adverse discharge disposition and the higher cost of hospitalization were taken as the dependent variables.
A total of 2244 patients who underwent surgical treatment for PD were identified from the database. The mean age was 64.22 ± 9.8 years and 68.7% (n = 1523) of the patients were male. The majority of the patients was discharged to home or self-care (87.9%, n = 1972). The majority of the procedures was performed at high-volume centers (64.8%, n = 1453), at academic institutions (85.33%, n = 1915), in urban areas (n = 2158, 96.16%), and at hospitals with a large bedsize (86.6%, n = 1907) in the West or South. Adverse discharge disposition was more likely in elderly patients (OR > 1, p = 0.011) with high comorbidity index (OR 1.508 [95% CI 1.148–1.98], p = 0.004) and those with complications (OR 3.155 [95% CI 1.202–8.279], p = 0.033). A hospital with a larger annual caseload was an independent predictor of adverse discharge disposition (OR 3.543 [95% CI 1.781–7.048], p < 0.001), whereas patients treated by physicians with high case volumes had significantly better outcomes (p = 0.006). The median total cost of hospitalization had increased by 6% from 2006 through 2010. Hospitals with a smaller case volume (OR 0.093, p < 0.001), private hospitals (OR 11.027, p < 0.001), nonteaching hospitals (OR 3.139, p = 0.003), and hospitals in the West compared with hospitals in Northeast and the Midwest (OR 1.885 [p = 0.033] and OR 2.897 [p = 0.031], respectively) were independent predictors of higher hospital cost. The mean length of hospital stay decreased from 2.03 days in 2006 to 1.55 days in 2010. There was no difference in the discharge disposition among academic versus nonacademic centers and rural versus urban hospitals (p > 0.05).
Elderly female patients with nonprivate insurance and high comorbidity index who underwent surgery at low-volume centers performed by a surgeon with a low annual case volume and the occurrence of postoperative complications were correlated with an adverse discharge disposition. High-volume, government-owned academic centers in the Northeast were associated with a lower cost incurred to the hospitals. It can be recommended that the widespread availability of this procedure across small, academic centers in rural areas may not only provide easier access to the patients but also reduces the total cost of hospitalization.
Anil Nanda, Shyamal C. Bir, Tanmoy K. Maiti, Subhas K. Konar, Symeon Missios, and Bharat Guthikonda
The clinical significance of the Simpson system for grading the extent of meningioma resection and its role as a predictor of the recurrence of World Health Organization (WHO) Grade I meningiomas have been questioned in the past, echoing changes in meningioma surgery over the years. The authors reviewed their experience in resecting WHO Grade I meningiomas and assessed the association between extent of resection, as evaluated using the Simpson classification, and recurrence-free survival (RFS) of patients after meningioma surgery.
Clinical and radiological information for patients with WHO Grade I meningiomas who had undergone resective surgery over the past 20 years was retrospectively reviewed. Simpson and Shinshu grading scales were used to evaluate the extent of resection. Statistical analysis was conducted using Kaplan-Meier curves and Cox proportional-hazards regression.
Four hundred fifty-eight patients were eligible for analysis. Overall tumor recurrence rates for Simpson resection Grades I, II, III, and IV were 5%, 22%, 31%, and 35%, respectively. After Cox regression analysis, Simpson Grade I (extensive resection) was revealed as a significant predictor of RFS (p = 0.003). Patients undergoing Simpson Grade I and II resections showed significant improvement in RFS compared with patients undergoing Grade III and IV resections (p = 0.005). Extent of resection had a significant effect on recurrence rates for both skull base (p = 0.047) and convexity (p = 0.012) meningiomas. Female sex and a Karnofsky Performance Scale score > 70 were also identified as independent predictors of RFS after resection of WHO Grade I meningioma.
In this patient cohort, a significant association was noted between extent of resection and rates of tumor recurrence. In the authors' experience the Simpson grading system maintains its relevance and prognostic value and can serve an important role for patient education. Even though complete tumor resection is the goal, surgery should be tailored to each patient according to the risks and surgical morbidity.
Tanmoy K. Maiti, Shyamal C. Bir, Devi Prasad Patra, Piyush Kalakoti, Bharat Guthikonda, and Anil Nanda
Spinal meningiomas are benign tumors with a wide spectrum of clinical and radiological features at presentation. The authors analyzed multiple clinicoradiological factors to predict recurrence and functional outcome in a cohort with a mean follow-up of more than 4 years. The authors also discuss the results of clinical studies regarding spinal meningiomas in the last 15 years.
The authors retrospectively reviewed the clinical and radiological details of patients who underwent surgery for spinal tumors between 2001 and 2015 that were histopathologically confirmed as meningiomas. Demographic parameters, such as age, sex, race, and association with neurofibromatosis Type 2, were considered. Radiological parameters, such as tumor size, signal changes of spinal cord, spinal level, number of levels, location of tumor attachment, shape of tumor, and presence of dural tail/calcification, were noted. These factors were analyzed to predict recurrence and functional outcome. Furthermore, a pooled analysis was performed from 13 reports of spinal meningiomas in the last 15 years.
A total of 38 patients were included in this study. Male sex and tumors with radiological evidence of a dural tail were associated with an increased risk of recurrence at a mean follow-up of 51.2 months. Ventral or ventrolateral location, large tumors, T2 cord signal changes, and poor preoperative functional status were associated with poor functional outcome at 1-year follow-up.
Spine surgeons must be aware of the natural history and risk factors of spinal meningiomas to establish a prognosis for their patients.
Jennifer A. Kosty, Juan Mejia-Munne, Rimal Dossani, Amey Savardekar, and Bharat Guthikonda
Jacques Jean Lhermitte (1877–1959) was among the most accomplished neurologists of the 20th century. In addition to working as a clinician and instructor, he authored more than 800 papers and 16 books on neurology, neuropathology, psychiatry, and mystical phenomena. In addition to the well-known “Lhermitte’s sign,” an electrical shock–like sensation caused by spinal cord irritation in demyelinating disease, Lhermitte was a pioneer in the study of the relationship between the physical substance of the brain and the experience of the mind. A fascinating example of this is the syndrome of peduncular hallucinosis, characterized by vivid visual hallucinations occurring in fully lucid patients. This syndrome, which was initially described as the result of a midbrain insult, also may occur with injury to the thalamus or pons. It has been reported as a presenting symptom of various tumors and as a complication of neurosurgical procedures. Here, the authors review the life of Lhermitte and provide a historical review of the syndrome of peduncular hallucinosis.
Marc Manix, Piyush Kalakoti, Miriam Henry, Jai Thakur, Richard Menger, Bharat Guthikonda, and Anil Nanda
Creutzfeldt-Jakob disease (CJD) is a rare neurodegenerative condition with a rapid disease course and a mortality rate of 100%. Several forms of the disease have been described, and the most common is the sporadic type. The most challenging aspect of this disease is its diagnosis—the gold standard for definitive diagnosis is considered to be histopatho-logical confirmation—but newer tests are providing means for an antemortem diagnosis in ways less invasive than brain biopsy. Imaging studies, electroencephalography, and biomarkers are used in conjunction with the clinical picture to try to make the diagnosis of CJD without brain tissue samples, and all of these are reviewed in this article. The current diagnostic criteria are limited; test sensitivity and specificity varies with the genetics of the disease as well as the clinical stage. Physicians may be unsure of all diagnostic testing available, and may order outdated tests or prematurely request a brain biopsy when the diagnostic workup is incomplete. The authors review CJD, discuss the role of brain biopsy in this patient population, provide a diagnostic pathway for the patient presenting with rapidly progressive dementia, and propose newer diagnostic criteria.
Sunil Kukreja, Piyush Kalakoti, Richard Murray, Menarvia Nixon, Symeon Missios, Bharat Guthikonda, and Anil Nanda
Incidence of C-2 fracture is increasing in elderly patients. Patient age also influences decision making in the management of these fractures. There are very limited data on the national trends of incidence, treatment interventions, and resource utilization in patients in different age groups with isolated C-2 fractures. The aim of this study is to investigate the incidence, treatment, complications, length of stay, and hospital charges of isolated C-2 fracture in patients in 3 different age groups by using the Nationwide Inpatient Sample (NIS) database. methods The data were obtained from NIS from 2002 to 2011. Data on patients with closed fractures of C-2 without spinal cord injury were extracted using ICD-9-CM diagnosis code 805.02. Patients with isolated C-2 fractures were identified by excluding patients with other associated injuries. The cohort was divided into 3 age groups: < 65 years, 65–80 years, and > 80 years. Incidence, treatment characteristics, inpatient/postoperative complications, and hospital charges (mean and total annual charges) were compared between the 3 age groups.
A total of 10,336 patients with isolated C-2 fractures were identified. The majority of the patients were in the very elderly age group (> 80 years; 42.3%) followed by 29.7% in the 65- to 80-year age group and 28% in < 65-year age group. From 2002 to 2011, the incidence of hospitalization significantly increased in the 65- to 80-year and > 80-year age groups (p < 0.001). However, the incidence did not change substantially in the < 65-year age group (p = 0.287). Overall, 21% of the patients were treated surgically, and 12.2% of the patients underwent nonoperative interventions (halo and spinal traction). The rate of nonoperative interventions significantly decreased over time in all age groups (p < 0.001). Regardless of treatment given, patients in older age groups had a greater risk of inpatient/postoperative complications, nonroutine discharges, and longer hospitalization. The mean hospital charges were significantly higher in older age groups (p < 0.001).
The incidence of hospitalization for isolated C-2 fractures is progressively increasing in older age groups. Simultaneously, there has been a steadily decreasing trend in the preference for nonoperative interventions. Due to more complicated hospital stay, longer hospitalizations, and higher rates of nonroutine discharges, the patients in older age groups seem to have a higher propensity for greater health care resource utilization.