Evaluation of intraventricular hemorrhage assessment methods for predicting outcome following intracerebral hemorrhage.

OBJECT: Intraventricular hemorrhage (IVH) associated with intracerebral hemorrhage (ICH) is an independent predictor of poor outcome. Clinical methods for evaluating IVH, however, are not well established. This study sought to determine the best IVH grading scale by evaluating the predictive accuracies of IVH, Graeb, and LeRoux scores in an independent cohort of ICH patients with IVH. Subacute IVH dynamics as well as the impact of external ventricular drain (EVD) placement on IVH and outcome were also investigated. METHODS: A consecutive cohort of 142 primary ICH patients with IVH was admitted to Columbia University Medical Center between February 2009 and February 2011. Baseline demographics, clinical presentation, and hospital course were prospectively recorded. Admission CT scans performed within 24 hours of onset were reviewed for ICH location, hematoma volume, and presence of IVH. Intraventricular hemorrhage was categorized according to IVH, Graeb, and LeRoux scores. For each patient, the last scan performed within 6 days of ictus was similarly evaluated. Outcomes at discharge were assessed using the modified Rankin Scale (mRS). Receiver operating characteristic analysis was used to determine the predictive accuracies of the grading scales for poor outcome (mRS score ≥ 3). RESULTS: Seventy-three primary ICH patients (51%) had IVH. Median admission IVH, Graeb, and LeRoux scores were 13, 6, and 8, respectively. Median IVH, Graeb and LeRoux scores decreased to 9 (p = 0.005), 4 (p = 0.002), and 4 (p = 0.003), respectively, within 6 days of ictus. Poor outcome was noted in 55 patients (75%). Areas under the receiver operating characteristic curve were similar among the IVH, Graeb, and LeRoux scores (0.745, 0.743, and 0.744, respectively) and within 6 days postictus (0.765, 0.722, 0.723, respectively). Moreover, the IVH, Graeb, and LeRoux scores had similar maximum Youden Indices both at admission (0.515 vs 0.477 vs 0.440, respectively) and within 6 days postictus (0.515 vs 0.339 vs 0.365, respectively). Patients who received EVDs had higher mean IVH volumes (23 ± 26 ml vs 9 ± 11 ml, p = 0.003) and increased incidence of Glasgow Coma Scale scores < 8 (67% vs 38%, p = 0.015) and hydrocephalus (82% vs 50%, p = 0.004) at admission but had similar outcome as those who did not receive an EVD. CONCLUSIONS: The IVH, Graeb, and LeRoux scores predict outcome well with similarly good accuracy in ICH patients with IVH when assessed at admission and within 6 days after hemorrhage. Therefore, any of one of the scores would be equally useful for assessing IVH severity and risk-stratifying ICH patients with regard to outcome. These results suggest that EVD placement may be beneficial for patients with severe IVH, who have particularly poor prognosis at admission, but a randomized clinical trial is needed to conclusively demonstrate its therapeutic value.

Spinal cord bypass surgery with intercostal and spinal accessory nerves: an anatomical feasibility study in human cadavers.

OBJECT: Despite extensive study, no meaningful progress has been made in encouraging healing and recovery across the site of spinal cord injury (SCI) in humans. Spinal cord bypass surgery is an unconventional strategy in which intact peripheral nerves rostral to the level of injury are transferred into the spinal cord below the injury. This report details the feasibility of using spinal accessory nerves to bypass cervical SCI and intercostal nerves to bypass thoracolumbar SCI in human cadavers. METHODS: Twenty-three human cadavers underwent cervical and/or lumbar laminectomy and dural opening to expose the cervical cord and/or conus medullaris. Spinal accessory nerves were harvested from the Erb point to the origin of the nerve's first major branch into the trapezius. Intercostal nerves from the T6-12 levels were dissected from the lateral border of paraspinal muscles to the posterior axillary line. The distal ends of dissected nerves were then transferred medially and sequentially inserted 4 mm deep into the ipsilateral cervical cord (spinal accessory nerve) or conus medullaris (intercostals). The length of each transferred nerve was measured, and representative distal and proximal cross-sections were preserved for axonal counting. RESULTS: Spinal accessory nerves were consistently of sufficient length to be transferred to caudal cervical spinal cord levels (C4-8). Similarly, intercostal nerves (from T-7 to T-12) were of sufficient length to be transferred in a tension-free manner to the conus medullaris. Spinal accessory data revealed an average harvested nerve length of 15.85 cm with the average length needed to reach C4-8 of 4.7, 5.9, 6.5, 7.1, and 7.8 cm. The average length of available intercostal nerve from each thoracic level compared with the average length required to reach the conus medullaris in a tension-free manner was determined to be as follows (available, required in cm): T-7 (18.0, 14.5), T-8 (18.7, 11.7), T-9 (18.8, 9.0), T-10 (19.6, 7.0), T-11 (18.8, 4.6), and T-12 (15.8, 1.5). The number of myelinated axons present on cross-sectional analysis predictably decreased along both spinal accessory and intercostal nerves as they coursed distally. CONCLUSIONS: Both spinal accessory and intercostal nerves, accessible from a posterior approach in the prone position, can be successfully harvested and transferred to their respective targets in the cervical spinal cord and conus medullaris. As expected, the number of axons available to grow into the spinal cord diminishes distally along each nerve. To maximize axon "bandwidth" in nerve bypass procedures, the most proximal section of the nerve that can be transferred in a tension-free manner to a spinal level caudal to the level of injury should be implanted. This study supports the feasibility of SAN and intercostal nerve transfer as a means of treating SCI and may assist in the preoperative selection of candidates for future human clinical trials of cervical and thoracolumbar SCI bypass surgery.

Spinal nerve root stimulation.

Spinal nerve root stimulation (SNRS) is a neuromodulation technique that is used to treat chronic pain. This modality places stimulator electrode array(s) along the spinal nerve roots, creating stimulation paresthesias within the distribution of the target nerve root(s), thereby treating pain in that same distribution. There are several different forms of spinal nerve root stimulation, depending upon the exact electrode positioning along the nerve roots. SNRS combines the minimally invasive nature, central location, and ease of placement of spinal cord stimulation with the focal targeting of stimulation paresthesias of peripheral nerve stimulation. This hybrid technique may be an effective alternative for patients in whom other forms of neurostimulation are either ineffective or inappropriate.

External ventricular drainage following aneurysmal subarachnoid haemorrhage.

External ventricular drain (EVD) placement is standard of care in the management of aneurysmal subarachnoid haemorrhage-associated hydrocephalus (aSAH). However, there are no guidelines for EVD placement and management after aSAH. Optimal EVD insertion conditions, techniques to reduce the risk of EVD-associated infection and aneurysmal rebleeding, and methods of EVD removal are critical, yet incompletely answered management variables. The present literature consists primarily of small studies with heterogeneous populations and variable outcome measures, and suggests the following: EVDs may increase the risk of rebleeding; EVDs are increasingly placed by non-neurosurgeons with unclear results; intraparenchymal ICP monitors may be safely considered (with or without spinal drainage) in the setting of difficult EVD placement; the optimal timing and manner of EVD removal has yet to be defined; and the efficacy of prophylactic systemic antibiotics and antibiotic-coated EVDs needs further investigation. Nevertheless, there are no definitive practice guidelines for EVD placement and management techniques in aSAH patients. Large prospective randomised trials are needed to definitively address important gaps in our understanding of EVD management principles in the neurocritical care setting.

Clinical grading scales in intracerebral hemorrhage.

Intracerebral hemorrhage (ICH) carries higher risk of long-term disability and mortality than any other form of stroke. Despite greater understanding of ICH pathophysiology, treatment options for this devastating condition remain limited. Moreover, a lack of a standard, universally accepted clinical grading scale for ICH has contributed to variations in management protocols and clinical trial designs. Grading scales are essential for standardized assessment and communication among physicians, selecting optimized treatment regiments, and designing effective clinical trials. There currently exist a number of ICH grading scales and prognostic models that have been developed for mortality and/or functional outcome, particularly 30 days after the ICH onset. Numerous reliable scales have been externally validated in heterogeneous populations. We extensively reviewed the inherent strengths and limitations of all the existing clinical ICH grading scales based on their development and validation methodology. For all ICH grading scales, we carefully observed study design and the definition and timing of outcome assessment to elucidate inconsistencies in grading scale derivation and application. Ultimately, we call for an expansive, prospective, multi-center clinical outcome study to clearly define all aspects of ICH, establish ideal grading scales, and standardized management protocols to enable the identification of novel and effective therapies in ICH.