Jonathan A. Forbes

Recovery from sports-related concussion: Days to return to neurocognitive baseline in adolescents versus young adults

Background: Sports-related concussions (SRC) among high school and collegiate athletes represent a significant public health concern. The Concussion in Sport Group (CIS) recommended greater caution regarding return to play with children and adolescents. We hypothesized that younger athletes would take longer to return to neurocognitive baseline than older athletes after a SRC. Methods: Two hundred adolescent and young adult athletes who suffered a SRC were included in our clinical research cohort. Of the total participants, 100 were assigned to the 13-16 year age group and 100 to the 18-22 year age group and were matched on the number of prior concussions. Each participant completed baseline and postconcussion neurocognitive testing using the Immediate Post-Concussion assessment and Cognitive Testing (ImPACT) test battery. Return to baseline was defined operationally as post-concussion neurocognitive and symptom scores being equivalent to baseline using reliable change index (RCI) criteria. For each group, the average number of days to return to cognitive and symptom baseline were calculated. Independent sample t-tests were used to compare the mean number of days to return to baseline. Results: Significant differences were found for days to return to baseline between 13-16 year olds and 18-22 year olds in three out of four neurocognitive measures and on the total symptom score. The average number of days to return to baseline was greater for 13-16 year olds than for 18-22 year olds on the following variables: Verbal memory (7.2 vs. 4.7, P = 0.001), visual memory (7.1 vs. 4.7, P = 0.002), reaction time (7.2 vs. 5.1 P = 0.01), and postconcussion symptom scale (8.1 vs. 6.1, P = 0.026). In both groups, greater than 90% of athletes returned to neurocognitive and symptom baseline within 1 month. Conclusions: Our results in this clinical research study show that in SRC, athletes 13-16 years old take longer to return to their neurocognitive and symptom baselines than athletes 18-22 years old.

Response to acute concussive injury in soccer players: is gender a modifying factor?

OBJECT Several studies have suggested a gender difference in response to sports-related concussion (SRC). The Concussion in Sport group did not include gender as a modifying factor in SRC, concluding that the evidence at that point was equivocal. In the present study the authors endeavored to assess acute neurocognitive and symptom responses to an SRC in equivalent cohorts of male and female soccer players. The authors hypothesized that female athletes would experience greater levels of acute symptoms and neurocognitive impairment than males. METHODS Baseline symptom and neurocognitive scores were determined in 40 male and 40 female soccer players by using the Immediate Postconcussion Assessment and Cognitive Testing (ImPACT) scale prior to any SRC. After sustaining an SRC, each athlete completed postconcussion ImPACT tests and was carefully matched on a wide array of biopsychosocial variables. Baseline symptom and neurocognitive test scores were compared, and their acute symptoms and neurocognitive responses to concussive injury were assessed. RESULTS Specific a priori hypotheses about differences between males and females at baseline and at postconcussion measurements of verbal and visual memory ImPACT scores were evaluated according to simple main effects of the gender variable and according to baseline-to-postconcussion main effect and interaction of 2 × 2 split-plot ANOVA. Neither the interaction nor the main effects nor the simple main effects for either ImPACT variable were found to be statistically significant. Exploratory ANOVAs applied to the remaining ImPACT variables of visualmotor speed, reaction time, impulse control, and symptom total scores revealed only a single statistically significant baseline-to-postconcussion main effect for the symptom total. CONCLUSIONS The results failed to replicate prior findings of gender-specific baseline neurocognitive differences in verbal and visual memory. The findings also indicated no differential gender-based acute response to concussion (symptoms or neurocognitive scores) among high school soccer players. The implications of these findings for the inclusion of gender as a modifying factor in this tightly matched cohort are addressed. Potential explanations for the null findings are discussed.

Porous polyethylene implant reconstruction of the orbit after resection of spheno-orbital meningiomas: A novel technique

BACKGROUND Spheno-orbital meningiomas (SOM) are complex tumors involving the middle cranial fossa and orbit. Following resection of these tumors, reconstruction of the orbit can be challenging. Inadequate reconstruction may lead to cosmetic deformities and functional complications. OBJECTIVE The development of a technique for orbital reconstruction which is technically straightforward, cost-effective, with an excellent functional and cosmetic outcome. TECHNIQUE Twelve patients with SOM each underwent a modified orbital-zygomatic craniotomy with osteotomies based on individual tumor location. After tumor resection, the lateral orbit and orbital roof, where necessary, were reconstructed using a 1 mm porous polyethylene sheet, customized to reconstruct the bony anatomy of the lateral and superior orbit and secured with 1.5×4 mm titanium screws into the orbital roof and rim. RESULTS All patients demonstrated stabilization or improvement of vision and satisfactory cosmetic outcomes. One complication (surgical site infection) was noted. Follow-up imaging was obtained at regular intervals. The resection cavity was easily visualized without interference from the implant in each case. One patient developed tumor recurrence requiring re-operation 20 months after the initial procedure. CONCLUSIONS Use of a 1mm porous polyethylene sheet for reconstruction of the lateral orbit offers an excellent functional and cosmetic outcome, does not interfere with postoperative imaging, is technically straightforward, and is cost-effective.

Structural brain injury in sports-related concussion

OBJECT Sports-related concussions (SRCs) represent a significant and growing public health concern. The vast majority of SRCs produce mild symptoms that resolve within 1-2 weeks and are not associated with imaging-documented changes. On occasion, however, structural brain injury occurs, and neurosurgical management and intervention is appropriate. METHODS A literature review was performed to address the epidemiology of SRC with a targeted focus on structural brain injury in the last half decade. MEDLINE and PubMed databases were searched to identify all studies pertaining to structural head injury in sports-related head injuries. RESULTS The literature review yielded a variety of case reports, several small series, and no prospective cohort studies. CONCLUSIONS The authors conclude that reliable incidence and prevalence data related to structural brain injuries in SRC cannot be offered at present. A prospective registry collecting incidence, management, and follow-up data after structural brain injuries in the setting of SRC would be of great benefit to the neurosurgical community.

Jugulotympanic paragangliomas: 75 years of evolution in understanding

Jugulotympanic paragangliomas were first described approximately 75 years ago. Since that time, there has been considerable evolution in knowledge of tumor biology, methods of classification, and appropriate management strategies. This paper attempts to summarize these gains in information.

Functional and Structural Traumatic Brain Injury in Equestrian Sports: A Review of the Literature.

OBJECTIVE Sports-related concussions and traumatic brain injury (TBI) represent a growing public health concern. We reviewed the literature regarding equestrian-related brain injury, ranging from concussion to severe TBI. METHODS A literature review was performed to address the epidemiology of sports-related concussion and TBI in equestrian-related sports. MEDLINE and PUBMED databases were searched to identify all studies pertaining to brain injury in equestrian-related sports. We included two broad types of brain injury using a distinction established in the literature: 1) TBI with functional impairment, including concussion, or mild TBI, with negative imaging findings; and 2) TBI with structural impairment, with positive imaging and at least one of the following pathologies identified: subdural hemorrhage, epidural hemorrhage, subarachnoid hemorrhage, intraparenchymal hemorrhage, cerebral contusions, and skull fractures. RESULTS Our literature search yielded 199 results. We found 26 studies describing functional TBI and 25 mentioning structural TBI, and 8 including both. Of all modern sporting activities, equestrian sports were found to cause some of the highest rates of total bodily injury, severe brain injury, and mortality. Concussions comprise 9.7%-15% of all equestrian-related injuries brought to hospitals for evaluation. Structural TBI was rare, and documentation of these injuries was poor. Although demographic risk factors like age and sex are minimally discussed in the literature, two studies identified a protective effect of increasing rider experience on all forms of bodily injury. However, it remains unclear whether increasing rider experience protects specifically against head injury. Finally, rates of helmet use in horseback riding remain dismally low-ranging from 9%-25%, depending on the activity. These low rates have persisted over time, despite evidence in this literature that helmets lead to an absolute risk reduction for head injury of 40%-50% in equestrian sports. CONCLUSIONS Equestrian-related functional and structural TBI represent a significant public health burden. Rider and horse characteristics make the sport uniquely dangerous, as the athlete has limited control over an animal weighing a thousand pounds. Helmet use rates remain very low despite clear evidence of risk reduction. Health care providers are strongly urged to lobby professional and governmental organizations for mandatory helmet use in all equestrian sports.

Experience with 25 years of dorsal root entry zone lesioning at a single institution.

Background: The authors sought to assess long-term efficacy, surgical morbidity, and postoperative quality of life in patients who have undergone dorsal root entry zone (DREZ) lesioning. Methods: We utilized the electronic chart system at our institution to identify patients who underwent DREZ lesioning since 1986. Of the patients that were able to be identified, 19 (12 males and 7 females) patients were able to be contacted at time of data collection. The mean age was 47 years (ranging from 23 to 70 years) with average preoperative pain duration of 12.5 years and average follow-up of 4.9 years. Results: Of the 19 patients we were able to contact, 7 (37%) patients experienced “excellent” postoperative (complete) pain relief with another 6 (32%) reporting “good” improvement. Three (16%) patients reported “mild” pain relief, while three (16%) patients reported poor results. Sixteen patients (84%) stated they would undergo DREZ lesioning again, if given a choice. Two patients (11%) had objective evidence of a new, mild motor deficit postoperatively. More than half of the patients, who answered, reported “good” quality of life. Two-sample unequal variance t-test showed no statistically significant difference in pain improvement between brachial plexus avulsion and end-zone spinal cord injury pain. Conclusion: With appropriate patient selection, DREZ lesioning is an efficacious and durable procedure that can be performed with low morbidity and good patient outcomes.

Sports-related concussion in helmeted vs. Unhelmeted athletes: who fares worse?

In the management of sports-related concussion, little is known about the effect of wearing or not wearing a helmet (i. e., helmet status) on the acute outcomes of concussed athletes. We endeavored to assess acute neurocognitive and symptom changes after SRC in helmeted vs. unhelmeted athletes. In a retrospective study, 1 025 athletes from 2 regional databases sustained a SRC. Athletes were matched by age, gender, number of prior concussions, and days to post-concussion test, yielding a final cohort of 138 athletes. For each group of 69, differences in post-concussion neurocognitive and symptom scores were compared using group mean differences as well as reliable change index (RCI) scores set at the 80% confidence interval. With gender, prior concussions, and days to post-concussion test similar in each group, using group mean change scores and RCI methodology, we found no significant differences between the helmeted and unhelmeted groups in 4 neurocognitive tests and one total symptom score. In a cohort of carefully matched athletes from 2 regional concussion centers, helmet status was unrelated to neurocognitive scores and total symptoms in athletes after suffering a SRC. These findings suggest that acute outcomes in helmeted vs. unhelmeted sports are quite similar.

Findings on Preoperative Brain MRI Predict Histopathology in Children with Cerebellar Neoplasms

Background/Aims: The majority of pediatric patients with cerebellar neoplasms harbor pilocytic astrocytomas (PAs), medulloblastomas, or ependymomas. Knowledge of a preoperative likelihood of histopathology in this group of patients has the potential to influence many aspects of care. Previous studies have demonstrated hyperintensity on diffusion-weighted imaging to correlate with medulloblastomas. Recently, measurement of T2-weighted signal intensity (T2SI) was shown to be useful in identification of low-grade cerebellar neoplasms. The goal of this study was to assess whether objective findings on these MRI sequences reliably correlated with the underlying histopathology. Methods: We reviewed the radiologic findings of 50 pediatric patients who underwent resection of a cerebellar neoplasm since 2003 at our institution. Region of interest placement was used to calculate the relative diffusion-weighted signal intensity (rDWSI) and relative T2SI (rT2SI) of each neoplasm. Results: Tukey’s multiple comparison test demonstrated medulloblastomas to have significantly higher rDWSIs than PAs/ependymomas, and PAs to have significantly higher rT2SIs than medulloblastomas/ependymomas. A simple method consisting of sequential measurement of rDWSI and rT2SI to predict histopathology was then constructed. Using this method, 39 of 50 (78%) tumors were accurately predicted. Conclusion: Measurement of rDWSI and rT2SI using standard MRI of the brain can be used to predict histopathology with favorable accuracy in pediatric patients with cerebellar tumors.

Decreased Rate of CSF Leakage Associated with Complete Reconstruction of Suboccipital Cranial Defects.

Background Cerebrospinal fluid (CSF) leakage represents a major source of morbidity following microvascular decompression (MVD) surgery. The objective of this study was to retrospectively assess whether complete versus incomplete reconstruction of the suboccipital cranial defect influences the incidence of CSF leakage following MVD. Methods We reviewed the charts of 100 patients who consecutively underwent MVD for trigeminal neuralgia by two attending neurosurgeons between July 2004 and April 2010. Operative variables including incomplete or complete calvarial reconstruction, primary dural closure or dural closure with adjunct, and use of lumbar drainage were recorded. The effect of complete calvarial reconstruction on the incidence of postoperative CSF leakage was examined using a multivariate logistic regression model. Results Of the 36 patients whose wound closure was reconstructed with a complete cranioplasty, 2 (5.6%) patients experienced a postoperative CSF leak. Of the 64 patients whose wound closure was augmented with an incomplete cranioplasty, 15 (23.4%) experienced a postoperative CSF leak. There was suggestive but inconclusive evidence that the risk of CSF leakage following MVD was smaller with complete reconstruction of calvarial defect than with incomplete reconstruction (two-sided p value = 0.059), after accounting for age, dural closure method, use of lumbar drainage, and previous MVD. Conclusion Complete reconstruction of the suboccipital cranial defect decreases the risk of CSF leakage.