Publications

OBJECTIVES: The American population above 65 years of age will double by 2050, and more nonagenarians will present to neurosurgeons for treatment for subdural hematomas (SDH), common in the elderly. Healthcare providers, and patients relatives, often choose treatment when there is little chance of recovery. Hospital mortality is 24% (n = 5) in chronic subdural hematoma (cSDH) patients over 65 years, but there are no studies on cSDH outcomes in patients aged over 90 years. This retrospective study evaluates outcomes in this population. METHODS: We reviewed all patients with cSDH between December 2005 and December 2011. We analyzed charts of patients aged 90 years and older. Patient demographics, Glagow Coma Scale (GCS) at presentation, medical co-morbidities, length of stay, disposition, treatment, and radiographic characteristics were abstracted. RESULTS: Twenty-one patients aged 90 or older with 24 admissions for cSDH were identified. Median age was 92 (SD = 2.5); 76% (n = 16) underwent surgery. Median presentation GCS was 14. Disposition to home, rehabilitation facility, nursing home, hospice, or death were not significantly different between conservative and operative groups (P = 0.10), nor was admission GCS (P = 0.59). The size of SDH was significantly (P = 0.02) larger in the operative group. Overall, only 24% (n = 5) of patients were discharged home. CONCLUSION: Clinical presentation with cSDH is a sentinel event for patients aged 90 years or older; 67% have surgical intervention. Disposition does not vary with surgical or non-surgical treatment. Only 24% of patients of this age group presenting with cSDH return home despite a good admission GCS.

We measured quantitative cortical mantle cerebral blood flow (CBF) by stable xenon computed tomography (CT) within the first 12 h after severe traumatic brain injury (TBI) to determine whether neurologic outcome can be predicted by CBF stratification early after injury. Stable xenon CT was used for quantitative measurement of CBF (mL/100 g/min) in 22 cortical mantle regions stratified as follows: low (0-8), intermediate (9-30), normal (31-70), and hyperemic (>70) in 120 patients suffering severe (Glasgow Coma Scale [GCS] score ≤8) TBI. For each of these CBF strata, percentages of total cortical mantle volume were calculated. Outcomes were assessed by Glasgow Outcome Scale (GOS) score at discharge (DC), and 1, 3, and 6 months after discharge. Quantitative cortical mantle CBF differentiated GOS 1 and GOS 2 (dead or vegetative state) from GOS 3-5 (severely disabled to good recovery; p0.001). Receiver operating characteristic (ROC) curve analysis for percent total normal plus hyperemic flow volume (TNHV) predicting GOS 3-5 outcome at 6 months for CBF measured 6 and 12 h after injury showed ROC area under the curve (AUC) cut-scores of 0.92 and 0.77, respectively. In multivariate analysis, percent TNHV is an independent predictor of GOS 3-5, with an odds ratio of 1.460 per 10 percentage point increase, as is initial GCS score (OR=1.090). The binary version of the Marshall CT score was an independent predictor of 6-month outcome, whereas age was not. These results suggest that quantitative cerebral cortical CBF measured within the first 6 and 12 h after TBI predicts 6-month outcome, which may be useful in guiding patient care and identifying patients for randomized clinical trials. A larger multicenter randomized clinical trial is indicated.

OBJECT: Minimizing secondary brain injuries after traumatic brain injury (TBI) in children is critical to maximizing neurological outcome. Brain tissue oxygenation monitoring (as measured by interstitial partial pressure of O2 [PbO2]) is a new tool that may aid in guiding therapies, yet experience in children is limited. This study aims to describe the authors experience of PbO2 monitoring after TBI. It was hypothesized that PbO2 thresholds could be established that were associated with favorable neurological outcome, and it was determined whether any relationships between PbO2 and other important clinical variables existed. METHODS: Forty-six children with severe TBI (Glasgow coma scale score ≤ 8 after resuscitation) who underwent PbO2 and brain temperature monitoring between September 2004 and June 2008 were studied. All patients received standard neurocritical care, and 24 were concurrently enrolled in a trial of therapeutic early hypothermia (n = 12/group). The PbO2 was measured in the uninjured frontal cortex. Hourly recordings and calculated daily means of various variables including PbO2, intracranial pressure (ICP), cerebral perfusion pressure (CPP), mean arterial blood pressure, partial pressure of arterial O2, and fraction of inspired O2 were compared using several statistical approaches. Glasgow outcome scale scores were determined at 6 months after injury. RESULTS: The mean patient age was 9.4 years (range 0.1-16.5 years; 13 girls) and 8554 hours of monitoring were analyzed (PbO2 range 0.0-97.2 mm Hg). A PbO2 of 30 mm Hg was associated with the highest sensitivity/specificity for favorable neurological outcome at 6 months after TBI, yet CPP was the only factor that was independently associated with favorable outcome. Surprisingly, instances of preserved PbO2 with altered ICP and CPP were observed in some children with unfavorable outcomes. CONCLUSIONS: Monitoring of PbO2 demonstrated complex interactions with clinical variables reflecting intracranial dynamics using this protocol. A higher threshold than reported in studies in adults was suggested as a potential therapeutic target, but this threshold was not associated with improved outcomes. Additional studies to assess the utility of PbO2 monitoring after TBI in children are needed.

Previous work suggests that the ability to selectively attend to and resolve conflicting information may be the most enduring cognitive deficit following mild traumatic brain injury (mTBI). The current study used fMRI to evaluate potential differences in hemodynamic activation in 22 mTBI patients and 22 carefully matched healthy controls (HC) during a multimodal selective attention task (numeric Stroop). Behavioral data indicated faster reaction times for congruent versus incongruent trials and for stimuli presented at 0.66 compared to 0.33 Hz across both groups, with minimal differences in behavioral performance across the groups. Similarly, there were no group-wise differences in functional activation within lateral and medial prefrontal cortex during the execution of cognitive control (incongruent versus congruent trials). In contrast, within-group comparisons indicated robust patterns of attention-related modulations (ARM) within the bilateral dorsolateral prefrontal cortex and bilateral visual streams for HC but not mTBI patients. In addition, mTBI patients failed to exhibit task-induced deactivation within the default-mode network (DMN) under conditions of higher attentional load. In summary, in spite of near normal behavioral performance, current results suggest within-group abnormalities during both the top-down allocation of visual attention and in regulating the DMN during the semi-acute stage of mTBI.

OBJECTIVE: To evaluate the efficacy of routine follow-up CT scans of the head after complicated mild traumatic brain injury (TBI). METHODS: 74 English language studies published from 1999 to February 2011 were reviewed. The papers were found by searching the PubMed database using a combination of keywords according to Cochrane guidelines. Excluding studies with missing or inappropriate data, 1630 patients in 19 studies met the inclusion criteria: complicated mild TBI, defined as a GCS score 13-15 with abnormal initial CT findings and the presence of follow-up CT scans. For these studies, the progression and type of intracranial haemorrhage, time from trauma to first scan, time between first and second scans, whether second scans were obtained routinely or for neurological decline and the number of patients who had a neurosurgical intervention were recorded. RESULTS: Routine follow-up CT scans showed hemorrhagic progression in 324 patients (19.9%). Routine follow-up head CT scans did not predict the need for neurosurgical intervention (p=0.10) but a CT scan of the head performed for decline in status did (p=0.00046). For the 56 patients (3.4%) who declined neurologically, findings on the second CT scan were worse in 38 subjects (67%) and unchanged in the rest. Overall, 39 patients (2.4%) underwent neurosurgical intervention. CONCLUSION: Routine follow-up CT scans rarely alter treatment for patients with complicated mild TBI. Follow-up CT scans based on neurological decline alter treatment five times more often than routine follow-up CT scans.

OBJECTIVE The subjective view of psychiatric patients on mechanical restraint is to be examined and the necessity of dealing with this issue consciously is to be pointed out. METHODS 14 patients, who experienced mechanical restraint during a stay in a psychiatric hospital, were questioned in a problem-centered, semi-structured interview. Data analysis was based on inductive category formation, using Mayring s qualitative content analysis. RESULTS Mechanical restraint is primarily experienced as stressful or traumatizing. Patients complain about a lack of information, support and response when referring to mechanical restraint. CONCLUSION Reports of patients who have experienced coercive measures should be increasingly integrated into clinical practice.

OBJECT: Patients with mild traumatic brain injury (mTBI) only rarely need neurosurgical intervention; however, there is a subset of patients whose condition will deteriorate. Given the high resource utilization required for interhospital transfer and the relative infrequency of the need for intervention, this study was undertaken to determine how often patients who were transferred required intervention and if there were factors that could predict that need. METHODS: The authors performed a retrospective review of cases involving patients who were transferred to the University of New Mexico Level 1 trauma center for evaluation of mTBI between January 2005 and December 2009. Information including demographic data, lesion type, need for neurosurgical intervention, and short-term outcome was recorded. RESULTS: During the 4-year study period, 292 patients (age range newborn to 92 years) were transferred for evaluation of mTBI. Of these 292 patients, 182 (62.3%) had an acute traumatic finding of some kind; 110 (60.4%) of these had a follow-up CT to evaluate progression, whereas 60 (33.0%) did not require a follow-up CT. In 15 cases (5.1% overall), the patients were taken immediately to the operating room (either before or after the first CT). Only 4 patients (1.5% overall) had either clinical or radiographic deterioration requiring delayed surgical intervention after the second CT scan. Epidural hematoma (EDH) and subdural hematoma (SDH) were both found to be significantly associated with the need for surgery (OR 29.5 for EDH, 95% CI 6.6-131.8; OR 9.7 for SDH, 95% CI 2.4-39.1). There were no in-hospital deaths in the series, and 97% of patients were discharged with a Glasgow Coma Scale score of 15. CONCLUSIONS: Most patients who are transferred with mTBI who need neurosurgical intervention have a surgical lesion initially. Only a very small percentage will have a delayed deterioration requiring surgery, with EDH and SDH being more concerning lesions. In most cases of mTBI, triage can be performed by a neurosurgeon and the patient can be observed without interhospital transfer.

OBJECTIVE: Cranial base chordomas are difficult lesions to treat. The endoscopic endonasal approach (EEA) takes advantage of the natural sinus corridor and may provide a less invasive approach for these midline tumors. METHODS: Patients undergoing EEA for chordomas were selected from a database of more than 800 consecutive patients undergoing EEA at the University of Pittsburgh Medical Center and were retrospectively evaluated. Additionally, a systematic review of the literature of endoscopic endonasally resected chordomas was performed and compared with our personal experience. RESULTS: Twenty patients (8 females and 12 males) underwent 26 endoscopic EEAs for cranial base chordomas. Eight chordomas (40%) were recurrent. Treatment of the 12 newly diagnosed chordomas included 8 total resections (66.7%), 2 near total resections (16.7%), and 2 subtotal resections (16.7%). Treatment of the 8 recurrent chordomas included 1 gross total resection (12.5%), 2 near total resections (25.0%), and 5 subtotal resections (62.5%). Two patients (10%) had recurrences, and 5 patients (25%) progressed during the mean follow-up period of 13 months (range, 1-45 months). Five patients (25%) underwent re-resection, 1 patient was lost to follow-up, and 1 patient died secondary to progression of disease. There was 1 intraoperative vascular complication with no sequelae. The cerebrospinal fluid leak rate was 25%, and there were no cases of bacterial meningitis. The incidence of a new permanent neurological complication was 5%. A systematic review of the literature yielded a total of 26 cases of chordomas resected via a completely endoscopic endonasal technique. CONCLUSION: Endoscopic endonasal resection of cranial base chordomas is safe once adequate experience is gained with the technique. This approach provides the potential for, at the least, similar resections compared with traditional cranial base approaches while potentially limiting morbidity.

OBJECT: Current standard of care for patients with severe traumatic brain injury (TBI) is prophylactic treatment with phenytoin for 7 days to decrease the risk of early posttraumatic seizures. Phenytoin alters drug metabolism, induces fever, and requires therapeutic-level monitoring. Alternatively, levetiracetam (Keppra) does not require serum monitoring or have significant pharmacokinetic interactions. In the current study, the authors compare the EEG findings in patients receiving phenytoin with those receiving levetiracetam monotherapy for seizure prophylaxis following severe TBI. METHODS: Data were prospectively collected in 32 cases in which patients received levetiracetam for the first 7 days after severe TBI and compared with data from a historical cohort of 41 cases in which patients received phenytoin monotherapy. Patients underwent 1-hour electroencephalographic (EEG) monitoring if they displayed persistent coma, decreased mental status, or clinical signs of seizures. The EEG results were grouped into normal and abnormal findings, with abnormal EEG findings further categorized as seizure activity or seizure tendency. RESULTS: Fifteen of 32 patients in the levetiracetam group warranted EEG monitoring. In 7 of these 15 cases the results were normal and in 8 abnormal; 1 patient had seizure activity, whereas 7 had seizure tendency. Twelve of 41 patients in the phenytoin group received EEG monitoring, with all results being normal. Patients treated with levetiracetam and phenytoin had equivalent incidence of seizure activity (p = 0.556). Patients receiving levetiracetam had a higher incidence of abnormal EEG findings (p = 0.003). CONCLUSIONS: Levetiracetam is as effective as phenytoin in preventing early posttraumatic seizures but is associated with an increased seizure tendency on EEG analysis.

Serum magnesium concentration has a neuroprotective effect in experimental models of traumatic brain injury (TBI). This study was designed to assess the relationship between initial serum magnesium, cerebrospinal fluid (CSF) magnesium, neurological outcome and the efficacy of magnesium replacement therapy (MgSO4). A retrospective analysis was performed on a prospectively collected dataset from 216 patients admitted during 1996-2006 to the University of Pittsburgh Medical Center with severe TBI. Admission serum and CSF magnesium were dichotomized into low and normal magnesium concentration groups for serum and normal and high concentration groups for CSF. A logistic-regression analysis was performed with 6-month Glasgow Outcome Scale (GOS) scores as outcome variable. The outcome of a subset of 31 patients who presented with low serum magnesium and who were rapidly corrected within 24 h of admission was also analyzed. Low initial serum magnesium was measured in 56.67% of all patients. Patients with an initial serum magnesium of 1.3 mEq/L were 2.37 times more likely to have a poor outcome (CI: 1.18-4.78, p = 0.016). The prognostic significance of depressed serum magnesium remained, even in patients whose serum magnesium levels were corrected within 24 h (OR = 11.03, CI: 1.87-68.14, p = 0.008). Patients with an initial high CSF magnesium were 7.63 more likely to have a poor outcome (p = 0.05). Elevated CSF magnesium correlated with depressed serum magnesium only in patients with poor outcome (p = 0.013). Patients with low serum magnesium and high CSF magnesium are most likely to have poor outcome after severe TBI. Rapid correction of serum magnesium levels does not reverse the prognostic value of these markers.