Post-traumatic hydrocephalus following decompressive hemicraniectomy: Incidence and risk factors in a prospective cohort of severe TBI patients

BackgroundIn severe traumatic brain injury (TBI) patients undergoing decompressive hemicraniectomy (DHC), the rate of post-traumatic hydrocephalus (PTH) is high at 12–36%. Early diagnosis and shunt placement can improve outcomes. Herein, we examined the incidence of and predictors of PTH after craniectomy.MethodsA retrospective analysis of prospectively collected database of severe TBI patients at a single U.S. Level 1 trauma center from May 2000 to July 2014 was performed. Demographics, Injury Severity Score (ISS), Glasgow Coma Scale (GCS), bleeding pattern and time-to-cranioplasty were analyzed. Glasgow Outcome Scale (GOS) scores at 6 and 12-months were studied. Statistical significance was assessed at p < 0.05.ResultsA total of 402 patients were enrolled and 105 patients had DHC. Twenty-two (21.0%) of 105 required ventriculoperitoneal shunt (VPS), compared to 18 (6%) of 297 patients without DHC. There was increased odds ratio for shunting after DHC at 3.62 (95%CI:1.62–8.07; p < 0.01). Mean age at time of DHC was 43.8 ± 17.7 years old, and 81.9% were male. Subdural hematoma (SDH) was most common at 57.1%. Median time from admission to cranioplasty was 63 days. Patients who experienced PTH after DHC were younger (35.5 ± 17.7 versus 46.0 ± 17.7 years, p < 0.01) and had higher ISS scores (35 versus 26, p = 0.04) compared to patients without shunt after DHC.ConclusionsAfter severe TBI requiring hemicraniectomy, shunt-dependent hydrocephalus was 21%. Younger patients and higher ISS score were associated with PTH. Shunt-dependent patients achieved similar 6- and 12-month outcomes as those without PTH. Early diagnosis and shunt placement can enhance long-term neurological recovery.     

Long-term effects of concussion on relevancy-based modulation of somatosensory-evoked potentials

ObjectiveThe purpose of this investigation was to better understand the effects of concussions on the ability to selectively up or down-regulate incoming somatosensory information based on relevance.MethodsMedian nerve somatosensory-evoked potentials (SEPs) were elicited from electrical stimulation and recorded from scalp electrodes while participants completed tasks that altered the relevance of specific somatosensory information being conveyed along the stimulated nerve.ResultsWithin the control group, SEP amplitudes for task-relevant somatosensory information were significantly greater than for non-relevant somatosensory information at the earliest cortical processing potentials (N20-P27). Alternatively, the concussion history group showed similar SEP amplitudes for all conditions at early processing potentials, however a pattern similar to controls emerged later in the processing stream (P100) where both movement-related gating and facilitation of task-relevant information were present.ConclusionsPreviously concussed participants demonstrated impairments in the ability to up-regulate relevant somatosensory information at early processing stages. These effects appear to be chronic, as this pattern was observed on average several years after participants’ most recent concussion.SignificanceGiven the role of the prefrontal cortex in relevancy-based facilitation during movement-related gating, these findings lend support to the notion that this brain area may be particularly vulnerable to concussive forces.     

Is repeat head CT necessary in patients with mild traumatic intracranial hemorrhage

BackgroundPatients with traumatic intracranial hemorrhage (TIH) frequently receive repeat head CT scans (RHCT) to assess for progression of TIH. The utility of this practice has been brought into question, with some studies suggesting that in the absence of progressive neurologic symptoms, the RHCT does not lead to clinical interventions.MethodsThis was a retrospective review of consecutive patients with CT-documented TIH and GCS ≥ 13 presenting to an academic emergency department from 2009 to 2013. Demographic, historical, and physical exam variables, number of CT scans during admission were collected with primary outcomes of: neurological decline, worsening findings on repeat CT scan, and the need for neurosurgical intervention.ResultsOf these 1126 patients with mild traumatic intracranial hemorrhage, 975 had RHCT. Of these, 54 (5.5% (4.2–7.2 95 CI) had neurological decline, 73 (7.5% 5.9–9.3 95 CI) had hemorrhage progression on repeat CT scan, and 58 (5.9% 4.5–7.6 95 CI) required neurosurgical intervention. Only 3 patients (0.3% 0.1–0.9% 95 CI) underwent neurosurgical intervention due to hemorrhage progression on repeat CT scan without neurological decline. In this scenario, the number of RHCT scans needed to be performed to identify this one patient is 305.ConclusionsRHCT after initial findings of TIH and GCS ≥ 13 leading to a change to operative management in the absence of neurologic progression is a rare event. A protocol that includes selective RHCT including larger subdural hematomas or patients with coagulopathy (vitamin K inhibitors and anti-platelet agents) may be a topic for further study.