Kim J. Burchiel
Christopher M. Spearman, Madeline J. Quigley, Matthew R. Quigley and Jack E. Wilberger
The h index is a recently developed bibliometric that assesses an investigator's scientific impact with a single number. It has rapidly gained popularity in the physical and, more recently, medical sciences.
The h index for all 1120 academic neurosurgeons working at all Electronic Residency Application Service–listed training programs was determined by reference to Google Scholar. A random subset of 100 individuals was investigated in PubMed to determine the total number of publications produced.
The median h index was 9 (range 0–68), with the 75th, 90th, and 95th percentiles being 17, 26, and 36, respectively. The h indices increased significantly with increasing academic rank, with the median for instructors, assistant professors, associate professors, and professors being 2, 5, 10, and 19, respectively (p < 0.0001, Kruskal-Wallis; all groups significantly different from each other except the difference between instructor and assistant professor [Conover]). Departmental chairs had a median h index of 22 (range 3–55) and program directors a median of 17 (range 0–62). Plot of the log of the rank versus h index demonstrated a remarkable linear pattern (R2 = 0.995, p < 0.0001), suggesting that this is a power-law relationship.
A survey of the h index for all of academic neurosurgery is presented. Results can be used for benchmark purposes. The distribution of the h index within an academic population is described for the first time and appears related to the ubiquitous power-law distribution.
Matthew R. Quigley, Frank Schinco and J.Thomas Brown
✓ A case of familial anterior sacral meningocele associated with a dermoid tumor is reported. This patient presented with recurrent aseptic meningitis. The role of computerized tomography following metrizamide myelography in the diagnosis of this lesion is discussed.
Montell Salary, Matthew R. Quigley and Jack E. Wilberger Jr.
The authors of recent reports have suggested that smaller aneurysms are associated with more extensive sub-arachnoid hemorrhage (SAH), which could potentially presage poor outcome in patients harboring these lesions. The authors reviewed their clinical experience to determine if this theory has a basis in truth.
The authors undertook a retrospective review of a consecutive series of patients with aneurysmal SAH. Computed tomography scans and angiograms were studied to establish SAH scores and aneurysm size.
One hundred thirty-three patients were treated during a 2-year period (January 2003–December 2004). There were 101 female and 32 male patients whose mean age was 56.7 years. The location distribution of aneurysms that bled was as follows: anterior communicating artery (56 cases), posterior communicating artery (34 cases), middle cerebral artery (21 cases), posterior circulation (16 cases), and paraclinoid region (six cases). The mean aneurysm size was 6.2 mm (range 2–26 mm). The mean SAH score was 18.3 (not normally distributed, p < 0.01, D'Agostino–Pearson test). One hundred three patients underwent surgical exploration and placement of an aneurysm clip, 21 underwent deployment of a coil, and two underwent both therapies; seven patients died prior to intervention.
No correlation was found between aneurysm size and SAH score (rS = −0.023, p = 0.8) or between small aneurysm size and poor Glasgow Outcome Scale score (p = 0.13). In fact, the trend was the opposite. The SAH score did, however, correspond strongly with the admission Hunt and Hess grade (p < 0.0001), indicating the strong correlation between grade and volume of intracranial blood. Outcome was best explained in the multivariate analysis by the following factors: admission Hunt and Hess grade, age, and clinical vasospasm (p < 0.0001) with the proportion of cases correctly classified as 79.7%.
Evaluation of the results in the present clinical series suggests that there is no relation between aneurysm size and volume of subarachnoid blood. The volume of cisternal blood correlates with Hunt and Hess grade but is not an independent determinant of outcome. Outcome is related to the following triad of well-established clinical factors: Hunt and Hess grade, age, and clinical vasospasm.
Lucas Bernardes Miranda, Ernest Braxton, Joseph Hobbs and Matthew R. Quigley
Chronic subdural hematoma (CSDH) is perceived to be a “benign,” easily treated condition in the elderly, but reported follow-up periods are brief, usually limited to acute hospitalization.
The authors conducted a retrospective review of data obtained in a prospectively identified consecutive series of adult patients admitted to their institution between September 2000 and February 2008 and in whom there was a CT diagnosis of CSDH. Survival data were compared to life-table data.
Of the 209 cases analyzed, 63% were men and the mean age was 80.6 years (range 65–96 years). Primary surgical interventions performed were bur holes in 21 patients, twist-drill closed-system drainage in 44, and craniotomies in 72. An additional 72 patients were simply observed. Reoperations were recorded in 5 patients—4 who had previously undergone twist-drill drainage and 1 who had previously undergone a bur hole procedure (p = 0.41, chi-square analysis). Thirty-five patients (16.7%) died in hospital, 130 were discharged to rehabilitation or a skilled care facility, and 44 returned home. The follow-up period extended to a maximum of 8.3 years (median 1.45 years). Six-month and 1-year mortality rates were 26.3% and 32%, respectively.
In the multivariate analysis (step-wise logistic regression), the sole factor that predicted in-hospital death was neurological status on admission (OR 2.1, p = 0.02, for each step). Following discharge, the median survival in the remaining cohort was 4.4 years. In the Cox proportional hazards model, only age (hazard ratio [HR] 1.06/year, p = 0.02) and discharge to home (HR 0.24, p = 0.01) were related to survival, whereas the type of intervention, whether surgery was performed, size of subdural hematoma, amount of shift, bilateral subdural hematomas, and anticoagulant agent use did not affect the long- or short-term mortality rate.
Comparison of postdischarge survival and anticipated actuarial survival demonstrated a markedly increased mortality rate in the CSDH group (median survival 4.4 vs 6 years, respectively; HR 1.94, p = 0.0002, log-rank test). This excess mortality rate was also observed at 6 months postdischarge with evidence of normalization only at 1 year.
In this first report of the long-term outcome of elderly patients with CSDH the authors observed persistent excess mortality up to 1 year beyond diagnosis. This belies the notion that CSDH is a benign disease and indicates it is a marker of other underlying chronic diseases similar to hip fracture.
Brandon G. Chew, Christopher M. Spearman, Matthew R. Quigley and James E. Wilberger
Magnetic resonance imaging is frequently used to evaluate patients with traumatic brain injury in the acute and subacute setting, and it can detect injuries to the brainstem, which are often associated with poor outcomes. This study was undertaken to determine which MRI and clinical factors provide prognostic information in patients with traumatic brainstem injuries.
The authors performed a retrospective analysis of cases involving patients admitted to a Level I trauma center who were identified in a prospective database as having suffered traumatic brainstem injury identified on MRI. Patient outcomes were dichotomized to dead/vegetative versus functional groups. Standard demographic data, admission Glasgow Coma Scale (GCS) scores, results of the motor component of the GCS examination at admission and 24 hours later, CT scan findings, and peak intracranial pressure were collected from medical records. Volumetric analysis of each patient's injuries was performed with T2-weighted and gradient echo sequences. The T2-weighted MRI sequence for each patient was reviewed to determine the anatomical location of injury within the brainstem and whether the injury crossed the midline.
Thirty-six patients who met the study inclusion criteria were identified. At 6-month follow-up, 53% of these patients had poor outcomes and 47% had recovered. Patients with injuries to the medulla or deep bilateral injuries to the pons did not recover. The T2 volumes were found superior to gradient echo sequences in regard to predicting survival (ROC/AUC 0.67, p = 0.07 vs 0.60, p = 0.29, respectively), but neither reached statistical significance. The timing of MR image acquisition did not influence the findings. The time from admission to MRI did not differ significantly between the recovered group and the poor-outcome group (p = 0.52, Mann-Whitney test), and lesion size as measured by T2 volume did not vary with time to scan (R2 = 0.03, p = 0.3, linear regression). Performing a stepwise logistic regression with all the variables yielded the following factors related to recovery: crossing midline, p = 0.0156, OR 0.075; and 24-hour GCS motor score, p = 0.0045, OR = 2.25, c-statistic 0.913. Further examination of these 2 factors disclosed the following: none of 15 patients with midline-crossing lesions and a 24-hour GCS motor score of 4 or less recovered; conversely, 12 of 13 patients with lesions that did not cross midline recovered, regardless of GCS motor score.
Bilateral injury to the pons and medulla as detected on T2-weighted MRI sequences was associated with poor outcome in patients with brainstem injuries; T2 volumes were found superior to gradient echo sequences in regard to predicting survival, but neither reached statistical significance. When MRI findings were coupled with clinical examination findings, a strong correlation existed between poor outcome and the combination of bilateral brainstem injury and a motor GCS score of 4 or less 24 hours after admission.
Miguel Gelabert-González and Ramón Serramito-Garcia
Edward M. Marchan, Raymond F. Sekula Jr., Peter J. Jannetta and Matthew R. Quigley
✓Spinal glioblastomas multiforme (GBMs) are rare lesions of the central nervous system with a prognosis as poor as that of their intracranial counterpart. The authors present a case of a 50-year-old man with a GBM of the spinal cord treated with surgical removal of the mass and cordectomy after the onset of paraplegia. Six years later, the patient developed hepatitis C and received interferon therapy. Six months after the start of interferon therapy, magnetic resonance imaging revealed a right cerebellar mass pathologically consistent with a GBM. Despite aggressive treatment, the patient died 1 month later. Although intracranial dissemination of spinal GBMs has been reported, this case illustrates the longest reported interval between the occurrence of a spinal GBM and its intracranial dissemination. Thus, cordectomy should be considered as a reasonable alternative in patients with complete loss of neurological function at and below the level where they harbor a malignant spinal cord astrocytoma.
Raymond F. Sekula Jr., Andrew M. Frederickson, Peter J. Jannetta, Sanjay Bhatia and Matthew R. Quigley
Stereotactic radiosurgical rhizolysis using Gamma Knife surgery (GKS) is an increasingly popular treatment for medically refractory trigeminal neuralgia. Because of the increasing use of GKS for trigeminal neuralgia, clinicians are faced with the problem of choosing a subsequent treatment plan if GKS fails. This study was conducted to identify whether microvascular decompression (MVD) is a safe and effective treatment for patients who experience trigeminal neuralgia symptoms after GKS.
From their records, the authors identified 29 consecutive patients who, over a 2-year period, underwent MVD following failed GKS. During MVD, data regarding thickened arachnoid, adhesions between vessels and the trigeminal nerve, and trigeminal nerve atrophy/discoloration were noted. Outcome and complication data were also recorded.
The MVD procedure was completed in 28 patients (97%). Trigeminal nerve atrophy was noted in 14 patients (48%). A thickened arachnoid was noted in 1 patient (3%). Adhesions between vessels and the trigeminal nerve were noted in 6 patients (21%) and prevented MVD in 1 patient. At last follow-up, 15 patients (54%) reported an excellent outcome after MVD, 1 (4%) reported a good outcome, 2 (7%) reported a fair outcome, and 10 patients (36%) reported a poor outcome. After MVD, new or worsened facial numbness occurred in 6 patients (21%). Additionally, 3 patients (11%) developed new or worsened troubling dysesthesias.
Thickened arachnoid, adhesions between vessels and the trigeminal nerve, and trigeminal nerve atrophy/discoloration due to GKS did not prevent completion of MVD. An MVD is an appropriate and safe “rescue” therapy following GKS, although the risks of numbness and troubling dysesthesias appear to be higher than with MVD alone.