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Michael Zhang, Yi-Ren Chen, Steven D. Chang, and Anand Veeravagu

OBJECTIVE

Symptomatic vertebral hemangiomas (SVHs) are a very rare pathology that can present with persistent pain or neurological deficits that warrant surgical intervention. Given the relative rarity and difficulty in assessment, the authors sought to present a dedicated series of SVHs treated using stereotactic radiosurgery (SRS) to provide insight into clinical decision making.

METHODS

A retrospective review of a single institution's experience with hypofractionated radiosurgery for SVH from 2004 to 2011 was conducted to determine the clinical and radiographic outcomes following SRS treatment. The authors report and analyze the treatment course of 5 patients with 7 lesions, 2 of which were treated primarily by SRS.

RESULTS

Of the 5 patients studied, 4 presented with a chief complaint of pain refractory to conservative measures. Three patients reported dysesthesias, and 2 reported upper-extremity weakness. Following radiosurgery, 4 of 5 patients exhibited improvement in their primary symptoms (3 for pain and 1 for weakness), achieving a clinical response after a mean period of 1 year. In 2 cases there was 20%–40% reduction in lesion size in the most responsive dimension as noted on images. All treatments were well tolerated.

CONCLUSIONS

SRS for SVH is a safe and feasible treatment strategy, comparable to prior radiotherapy studies, and in select cases may successfully confer delayed decompressive effects. Additional investigation will determine future patient selection and how conformal SRS treatment can best be administered.

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Yanlu Zhang, Zheng Gang Zhang, Michael Chopp, Yuling Meng, Li Zhang, Asim Mahmood, and Ye Xiong

OBJECTIVE

The authors' previous studies have suggested that thymosin beta 4 (Tβ4), a major actin-sequestering protein, improves functional recovery after neural injury. N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP) is an active peptide fragment of Tβ4. Its effect as a treatment of traumatic brain injury (TBI) has not been investigated. Thus, this study was designed to determine whether AcSDKP treatment improves functional recovery in rats after TBI.

METHODS

Young adult male Wistar rats were randomly divided into the following groups: 1) sham group (no injury); 2) TBI + vehicle group (0.01 N acetic acid); and 3) TBI + AcSDKP (0.8 mg/kg/day). TBI was induced by controlled cortical impact over the left parietal cortex. AcSDKP or vehicle was administered subcutaneously starting 1 hour postinjury and continuously for 3 days using an osmotic minipump. Sensorimotor function and spatial learning were assessed using a modified Neurological Severity Score and Morris water maze tests, respectively. Some of the animals were euthanized 1 day after injury, and their brains were processed for measurement of fibrin accumulation and neuroinflammation signaling pathways. The remaining animals were euthanized 35 days after injury, and brain sections were processed for measurement of lesion volume, hippocampal cell loss, angiogenesis, neurogenesis, and dendritic spine remodeling.

RESULTS

Compared with vehicle treatment, AcSDKP treatment initiated 1 hour postinjury significantly improved sensorimotor functional recovery (Days 7–35, p < 0.05) and spatial learning (Days 33–35, p < 0.05), reduced cortical lesion volume, and hippocampal neuronal cell loss, reduced fibrin accumulation and activation of microglia/macrophages, enhanced angiogenesis and neurogenesis, and increased the number of dendritic spines in the injured brain (p < 0.05). AcSDKP treatment also significantly inhibited the transforming growth factor–β1/nuclear factor–κB signaling pathway.

CONCLUSIONS

AcSDKP treatment initiated 1 hour postinjury provides neuroprotection and neurorestoration after TBI, indicating that this small tetrapeptide has promising therapeutic potential for treatment of TBI. Further investigation of the optimal dose and therapeutic window of AcSDKP treatment for TBI and the associated underlying mechanisms is therefore warranted.

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Yanlu Zhang, Michael Chopp, Zheng Gang Zhang, Yi Zhang, Li Zhang, Mei Lu, Talan Zhang, Stefan Winter, Hemma Brandstätter, Asim Mahmood, and Ye Xiong

OBJECTIVE

Cerebrolysin is a neuropeptide preparation that mimics the properties of neurotrophic factors and has had beneficial effects in the treatment of neurodegenerative diseases, stroke, and traumatic brain injury (TBI). To further evaluate treatment schemes, the authors assessed the dose-response of Cerebrolysin on functional improvement in a rat model of mild TBI (mTBI).

METHODS

This dose-response study was a prospective, randomized, blinded, and placebo-controlled preclinical experiment. Male Wistar adult rats, subjected to mTBI induced by a closed head impact, were treated randomly with 0 (saline as placebo), 0.8, 2.5, or 7.5 ml/kg of Cerebrolysin 4 hours after mTBI and daily for a total of 10 consecutive days. A battery of cognitive and sensorimotor functional tests was performed over 90 days.

RESULTS

The primary outcome was functional improvement over the 90 days; animal weight and death were the secondary and safety outcomes, respectively. A significant (p < 0.001) dose effect of Cerebrolysin on cognitive recovery 3 months after injury was found. Cerebrolysin at a dose of ≥ 0.8 ml/kg significantly (p < 0.001) improved cognitive outcome. The higher dose (7.5 ml/kg) resulted in significantly better cognitive recovery than the lowest doses (0.8 ml/kg) but not relative to the 2.5-ml/kg dose. Cerebrolysin at a dose of 2.5 or 7.5 ml/kg also caused different onset times of significant improvement in sensorimotor function. No differences in body weight or mortality rate among the groups were found.

CONCLUSIONS

This preclinical randomized, placebo-controlled, and blinded study with a clinically relevant treatment scheme revealed that Cerebrolysin at doses of 0.8–7.5 ml/kg, administered 4 hours after mTBI and then once daily for a total of 10 consecutive days, improved functional outcomes 3 months after injury. A dose of 2.5 ml/kg is likely an optimal dose for the treatment of experimental mTBI.

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Yanlu Zhang, Michael Chopp, Yi Zhang, Zheng Gang Zhang, Mei Lu, Talan Zhang, Kuan-Han H. Wu, Li Zhang, Asim Mahmood, and Ye Xiong

OBJECTIVE

The authors previously demonstrated that Cerebrolysin is effective for treatment of mild closed head injury (CHI) when administered 4 hours after injury. The aim of this study was to determine Cerebrolysin’s effects on functional and histological outcomes in rats subjected to moderate CHI.

METHODS

In this randomized, blinded, and vehicle-controlled preclinical trial, male adult Wistar rats subjected to moderate CHI received either Cerebrolysin treatment at a dose of 2.5 ml/kg (n = 13) or vehicle (saline, n = 13) intraperitoneally administered daily for 10 days, starting at 4 hours after injury. Animals were subjected to cognitive and sensorimotor functional tests at multiple time points, and they were killed 3 months after injury. The brains were processed for analyses of neuronal cell loss, amyloid precursor protein, axonal damage, and neurogenesis.

RESULTS

Compared with rats treated with vehicle (saline), rats treated with Cerebrolysin had significantly increased numbers of neuroblasts and newborn mature neurons in the dentate gyrus (DG) and attenuated amyloid precursor protein accumulation and axonal damage in various brain regions, as well as decreased neuronal loss in the DG and cornu ammonis 3 (CA3) region of the hippocampus (p < 0.05). Global testing using generalized estimating equations showed a significant beneficial effect of Cerebrolysin treatment on sensorimotor functional outcomes from 1 day to 3 months after injury compared to that of saline treatment (p < 0.05). Compared with vehicle-treated rats, Cerebrolysin-treated rats showed significantly and robustly improved long-term (up to 3 months) cognitive functional recovery, as measured by social interaction, Morris water maze, novel object recognition, and odor recognition tests. In the Cerebrolysin-treated rats there were significant correlations between multiple histological outcomes and functional recovery evident 3 months after moderate CHI, as indicated by Pearson partial correlation analyses.

CONCLUSIONS

The authors’ findings demonstrate that Cerebrolysin treatment significantly improves long-term functional and histological outcomes in rats with moderate CHI, with functional outcomes significantly correlated with histological indices of neuroplasticity and neuroprotection. These data indicate that Cerebrolysin may be useful for the treatment of moderate CHI.

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Robert H. Bonow, James W. Bales, Ryan P. Morton, Michael R. Levitt, and Fangyi Zhang

Intracranial hypotension is a rare condition caused by spontaneous or iatrogenic CSF leaks that alter normal CSF dynamics. Symptoms range from mild headaches to transtentorial herniation, coma, and death. Duret hemorrhages have been reported to occur in some patients with this condition and are traditionally believed to be associated with a poor neurological outcome. A 73-year-old man with a remote history of spinal fusion presented with syncope and was found to have small subdural hematomas on head CT studies. He was managed nonoperatively and discharged with a Glasgow Coma Scale score of 15, only to return 3 days later with obtundation, fixed downward gaze, anisocoria, and absent cranial nerve reflexes. A CT scan showed Duret hemorrhages and subtle enlargement of the subdural hematomas, though the hematomas remained too small to account for his poor clinical condition. Magnetic resonance imaging of the spine revealed a large lumbar pseudomeningocele in the area of prior fusion. His condition dramatically improved when he was placed in the Trendelenburg position and underwent repair of the pseudomeningocele. He was kept flat for 7 days and was ultimately discharged in good condition. On long-term follow-up, his only identifiable deficit was diplopia due to an internuclear ophthalmoplegia. Intracranial hypotension is a rare condition that can cause profound morbidity, including tonsillar herniation and brainstem hemorrhage. With proper identification and treatment of the CSF leak, patients can make functional recoveries.

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Yanlu Zhang, Michael Chopp, Yuling Meng, Zheng Gang Zhang, Edith Doppler, Asim Mahmood, and Ye Xiong

Object

Cerebrolysin is a unique peptide preparation that mimics the action of neurotrophic factors. This study was designed to investigate the effects of acute treatment of experimental closed head injury (CHI) in rats with Cerebrolysin on neurological function.

Methods

Adult male Wistar rats (n = 60) were subjected to impact acceleration–induced CHI. Closed head injured rats received intraperitoneal injection of saline (n = 30) or Cerebrolysin (2.5 ml/kg, n = 30) starting 1 hour postinjury and administered once daily until they were killed (2 or 14 days after CHI). To evaluate functional outcome, the modified neurological severity score (mNSS), foot fault, adhesive removal, and Morris water maze (MWM) tests were performed. Animals were killed on Day 14 (n = 20) after injury, and their brains were removed and processed for measurement of neuronal cells, axonal damage, apoptosis, and neuroblasts. The remaining rats (n = 40) were killed 2 days postinjury to evaluate cerebral microvascular patency by fluorescein isothiocyanate (FITC)–dextran perfusion (n = 16) and to measure the expression of vascular endothelial growth factor (VEGF) and matrix metalloproteinase–9 (MMP-9) by using real-time reverse transcriptase-polymerase chain reaction (RT-PCR, n = 8) and by immunohistochemical analysis (n = 16).

Results

At 14 days post-CHI, the Cerebrolysin treatment group exhibited significant improvements in functional outcomes (the adhesive removal, mNSS, foot-fault, and MWM tests), and significantly more neurons and neuroblasts were present in the dentate gyrus (DG) (p < 0.05) compared with the saline-treated group (p < 0.05). At 2 days post-CHI, the Cerebrolysin group exhibited a significantly higher percentage of phosphorylated neurofilament H (pNF-H)–positive staining area in the striatum (p < 0.05), a significant increase in the percentage of FITC-dextran perfused vessels in the brain cortex (p < 0.05), a significant increase in the number of VEGF-positive cells (p < 0.05), and a significant reduction in the MMP-9 staining area (p < 0.05) compared with the saline-treated group. There was no significant difference in mRNA levels of MMP-9 and VEGF in the hippocampus and cortex 48 hours postinjury between Cerebrolysin- and saline-treated rats that sustained CHI.

Conclusions

Acute Cerebrolysin treatment improves functional recovery in rats after CHI. Cerebrolysin is neuroprotective for CHI (increased neurons in the dentate gyrus and the CA3 regions of the hippocampus and increased neuroblasts in the dentate gyrus) and may preserve axonal integrity in the striatum (significantly increased percentage of pNF-H–positive tissue in the striatum). Reduction of MMP-9 and elevation of VEGF likely contribute to enhancement of vascular patency and integrity as well as neuronal survival induced by Cerebrolysin. These promising results suggest that Cerebrolysin may be a useful treatment in improving the recovery of patients with CHI.

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Ye Xiong, Yanlu Zhang, Asim Mahmood, Yuling Meng, Zheng Gang Zhang, Daniel C. Morris, and Michael Chopp

Object

Thymosin β4 (Tβ4) is a regenerative multifunctional peptide. The aim of this study was to test the hypothesis that Tβ4 treatment initiated 6 hours postinjury reduces brain damage and improves functional recovery in rats subjected to traumatic brain injury (TBI).

Methods

Traumatic brain injury was induced by controlled cortical impact over the left parietal cortex in young adult male Wistar rats. The rats were randomly divided into the following groups: 1) saline group (n = 7); 2) 6 mg/kg Tβ4 group (n = 8); and 3) 30 mg/kg Tβ4 group (n = 8). Thymosin β4 or saline was administered intraperitoneally starting at 6 hours postinjury and again at 24 and 48 hours. An additional group of 6 animals underwent surgery without TBI (sham-injury group). Sensorimotor function and spatial learning were assessed using the modified Neurological Severity Score and the Morris water maze test, respectively. Animals were euthanized 35 days after injury, and brain sections were processed to assess lesion volume, hippocampal cell loss, cell proliferation, and neurogenesis after Tβ4 treatment.

Results

Compared with saline administration, Tβ4 treatment initiated 6 hours postinjury significantly improved sensorimotor functional recovery and spatial learning, reduced cortical lesion volume and hippocampal cell loss, and enhanced cell proliferation and neurogenesis in the injured hippocampus. The high dose of Tβ4 showed better beneficial effects compared with the low-dose treatment.

Conclusions

Thymosin β4 treatment initiated 6 hours postinjury provides both neuroprotection and neurorestoration after TBI, indicating that Tβ4 has promising therapeutic potential in patients with TBI. These data warrant further investigation of the optimal dose and therapeutic window of Tβ4 treatment for TBI and the associated underlying mechanisms.

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Michael D. Cusimano, Olli Saarela, Kirsten Hart, Shudong Zhang, and Steven R. McFaull

OBJECTIVE

The purpose of this study was to examine the population-based trends and factors associated with hospitalization of patients with traumatic brain injury (TBI) treated in the Emergency Department (ED) among those 65 years and older. The implications of these trends for neurosurgery and the broader society are discussed.

METHOD

With a national, mandatory reporting system of ED visits, the authors used Poisson regression controlling for age and sex to analyze trends in fall-related TBI of those aged 65 years and older between 2002 and 2017.

RESULTS

The overall rate of ED visits for TBI increased by 78%—from 689.51 per 100,000 (95% CI 676.5–702.8) to 1229 per 100,000 (95% CI 1215–1243) between 2002 and 2017. Females consistently experienced higher rates of fall-related TBI than did males. All age groups 65 years and older experienced significant increases in fall-related TBI rate over the study period; however, the highest rates occurred among the oldest individuals (90+ and 85–89 years). The hospital admission rate increased with age and Charlson Comorbidity Index. Males experienced both a higher admission rate and a greater percentage change in admission rate than females.

CONCLUSIONS

Rates of ED visits for fall-related TBI, hospitalization, and in-ED mortality in those aged 65 years and older are increasing for both sexes. The increasing hospital admission rate is related to more advanced comorbidities, male sex, and increasing age. These findings have significant implications for neurosurgical resources; they emphasize that health professionals should work proactively with patients, families, and caregivers to clarify goals of care, and they also outline the need for more high-level and, preferably, randomized evidence to support outcomes-based decisions. Additionally, the findings highlight the urgent need for improved population-based measures for prevention in not only this age demographic but in younger ones, and the need for changes in the planning of health service delivery and long-term care.

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Leland Rogers, Peixin Zhang, Michael A. Vogelbaum, Minesh P. Mehta, and on behalf of the authors