Functional neuroimaging and cognitive rehabilitation for people with traumatic brain injury

Cognitive deficits are a common consequence of traumatic brain injury. Although such deficits are amenable to rehabilitation, methods for individualizing cognitive interventions are still unrefined. Functional neuroimaging methods such as positron emission tomography and functional magnetic resonance imaging are emerging as possible technologies for measuring and monitoring the cerebral consequences of plasticity associated with brain injury and for evaluating the effectiveness of rehabilitation interventions. Functional neuroimaging may even enable more customized and efficient selection, design, or adaptation of individual cognitive rehabilitation programs. We review the current literature on functional neuroimaging after traumatic brain injury, relating these findings to cognitive rehabilitation. Overall, functional neuroimaging after traumatic brain injury has shown reliable differences in brain activity within several regions of frontal cortex, partly but not uniformly consistent with neuropsychological and structural findings in traumatic brain injury. We also outline a number of promising research opportunities for applying functional neuroimaging in traumatic brain injury settings, along with associated challenges.     

Neoplastic vs. traumatic spinal cord injury: an inpatient rehabilitation comparison

OBJECTIVE: To compare demographics, injury characteristics, and functional outcomes of patients with neoplastic spinal cord compression with those with traumatic spinal cord injuries. DESIGN: A prospective 5-yr comparison was undertaken comparing 34 patients with neoplastic spinal cord compression with 159 patients with traumatic spinal cord injury. RESULTS: Patients with neoplastic spinal cord compression were significantly older, more often female, and unemployed than patients with traumatic spinal cord injury. Neoplastic spinal cord compression presented more often with paraplegia involving the thoracic spine, and injuries were more often incomplete compared with traumatic spinal cord injury. Patients with neoplastic spinal cord compression had a significantly shorter rehabilitation length of stay compared with those with traumatic spinal cord injury. The neoplastic group had significantly lower FIM change scores. Both groups had similar FIM efficiencies and discharge to home rates. CONCLUSIONS: Patients with neoplastic spinal cord compression have different demographic and injury characteristics but can achieve comparable rates of functional gains as their traumatic spinal cord injury counterparts. Although patients with traumatic injuries achieve greater functional improvement, patients with neoplasms have a shorter rehabilitation length of stay and comparable FIM efficiencies and home discharge rates.     

Functional improvement after pediatric spinal cord injury

OBJECTIVE: To describe the functional gain (FGain) with pediatric spinal cord injury inpatient rehabilitation and to identify the relationship of various factors to FGain in pediatric spinal cord injury inpatient rehabilitation. DESIGN: Retrospective chart review of a series of 91 children with spinal cord injury admitted from 1993 to 1998 in a freestanding rehabilitation hospital. Admission and discharge functional status were assessed with the Pediatric Functional Independence Measure (WeeFIM) instrument for children 7 yr. The outcome measure is the FGain (difference between the discharge and admission functional status). RESULTS: Significant gains in functional status were observed in all patients. FGain was not significantly related to age, sex, length of inpatient rehabilitation, pathogenesis, or completeness or neurologic level of injury. However, there was a trend for higher FGain for patients with incomplete spinal cord injury and traumatic spinal cord injury. CONCLUSIONS: Functional improvement occurs with pediatric spinal cord injury inpatient rehabilitation. There is a trend for higher FGain in patients with less severe injury and traumatic injury. The lack of relationship between FGain and length of inpatient rehabilitation suggests that a variety of other factors influence the relationship between FGain and length of inpatient rehabilitation.     

Predictors of dysphagia after spinal cord injury.

OBJECTIVE: To quantify the incidence of swallowing deficits (dysphagia) and to identify factors that predict risk for dysphagia in the rehabilitation setting following acute traumatic spinal cord injury. DESIGN: Retrospective case-control study. SETTING: Freestanding rehabilitation hospital. PATIENTS: Data were collected on 187 patients with acute traumatic spinal cord injury admitted for rehabilitation over a 4-year period who underwent a swallowing screen, in which 42 underwent a videofluoroscopic swallowing study (VFSS). MAIN OUTCOME MEASURES: VFSS was performed on patients with suspected swallowing problems. Possible antecedents of dysphagia were recorded from the medical record including previous history of spine surgery, surgical approach and technique, tracheostomy and ventilator status, neurologic level of injury, ASIA Impairment Classification, orthosis, etiology of injury, age, and gender. RESULTS: On admission to rehabilitation 22.5% (n = 42) of spinal cord injury patients had symptoms suggesting dysphagia. In 73.8% (n = 31) of these cases, testing confirmed dysphagia (aspiration or requiring a modified diet), while VFSS ruled out dysphagia in 26.2% (n = 11) cases. Logistic regression and other analyses revealed three significant predictors of risk for dysphagia: age (p < .028), tracheostomy and mechanical ventilation (p < .001), and spinal surgery via an anterior cervical approach (p < .016). Other variables analyzed had no relation or at best a slight relation to dysphagia. Tracheostomy at admission was the strongest predictor of dysphagia. The combination of tracheostomy at rehabilitation admission and anterior surgical approach had an extremely high rate of dysphagia (48%). CONCLUSION: Swallowing abnormalities are present in a significant percentage of patients presenting to rehabilitation with acute traumatic cervical spinal cord injury. Patients with a tracheostomy appear to have a substantially increased risk of development of dysphagia, although other factors are also relevant. Risk of dysphagia should be evaluated to decrease the potential for morbidity related to swallowing abnormalities.     

Tensor magnetic resonance imaging in a case of mild traumatic brain injury with lowered verbal intelligence quotient.

We report the case of a 31-year-old man who had mild traumatic brain injury as a result of an accident at the age of 24 years. Seven years after the trauma, at the age of 31 years, he had a lower verbal intelligence quotient than performance intelligence quotient by the Wechsler Adult Intelligence Scale - Revised, and frontal lobe dysfunction, for example, difficulty in maintaining or changing the set as revealed by the Wisconsin Card Sorting Test Keio Version. Conventional brain magnetic resonance imaging had not shown any abnormalities. Abnormal brain areas were detected on magnetic resonance diffusion tensor imaging. On tractography, some fibres from the corpus callosum towards the frontal cortex were noted to be lacking in the left hemisphere compared with the right. The tractography results may explain the patient's lowered verbal intelligence quotient and focal left frontal lobe dysfunction. Diffusion tensor imaging is therefore helpful in detecting lesions in mild traumatic brain injury with diffuse axonal injury.     

Co-occurring traumatic brain injury and acute spinal cord injury rehabilitation outcomes

Macciocchi S, Seel RT, Warshowsky A, Thompson N, Barlow K. Co-occurring traumatic brain injury and acute spinal cord injury rehabilitation outcomes.ObjectiveTo determine the impact of co-occurring traumatic brain injury (TBI) on functional motor outcome and cognition during acute spinal cord injury (SCI) rehabilitation.DesignProspective, longitudinal cohort.SettingSingle-center National Institute of Disability and Rehabilitation Research SCI Model System.ParticipantsPersons aged 16 to 59 years (N=189) admitted for acute SCI rehabilitation during the 18-month recruitment window who met inclusion criteria.InterventionsNot applicable.Main Outcome MeasuresFIM Motor Scale (Rasch transformed) and acute rehabilitation length of stay (LOS).ResultsIn the tetraplegia sample, co-occurring TBI was not related to FIM Motor Scale scores or acute rehabilitation LOS despite having negative impacts on memory and problem solving. Persons with paraplegia who sustained co-occurring severe TBI had lower admission and discharge FIM Motor Scale scores and longer acute rehabilitation LOS than did persons with paraplegia and either no TBI or mild TBI. Persons with paraplegia and severe TBI had lower functional comprehension, problem solving, and memory and impairments on tests of processing speed compared with persons with paraplegia and no TBI, mild TBI, and moderate TBI. Persons with paraplegia and co-occurring mild and moderate TBI had equivalent acute rehabilitation motor outcomes and cognitive functioning compared with persons with paraplegia and no TBI.ConclusionsThis study provides evidence that persons aged 16 to 59 years with paraplegia and co-occurring severe TBI had worse motor outcomes and longer acute rehabilitation LOS than did persons with paraplegia and no TBI. Impairments in processing speed, comprehension, memory, and problem solving may explain suboptimal motor skill acquisition. Research with larger samples is required to determine whether mild and moderate TBI impact acute rehabilitation motor outcomes and LOS.     

Early unplanned transfers from inpatient rehabilitation

OBJECTIVE: To identify characteristics of patients who transfer off inpatient rehabilitation to a surgical or medical unit before completion of their rehabilitation program. DESIGN: A retrospective 9-yr chart review of patients transferred off the rehabilitation unit at a regional level 1 trauma center due to medical complications. RESULTS: Of 3072 patient admissions, 250 (8%) were transferred to an acute medical or surgical unit, and 55 (22%) of those transfers were within 3 days. Of the 250 patients, 33% had traumatic brain injury, 23% had spinal cord injury, 24% had stroke, 2% had amputations, 18% were in other diagnostic groups, and 23% were >64 yrs of age. When patients transferred early, only 47% were ultimately discharged to home, compared with approximately 72% of all discharges. The most common reasons for early transfer in these patients were infection (22%) and pulmonary complications (14%). Risk factors for early discharge included age of >64 yrs, spinal cord injury, or amputation. CONCLUSION: Patients admitted to the inpatient rehabilitation unit who have spinal cord injuries, amputations, or are >64 yrs old may have more medical/surgical complications. More detailed study of this patient population may help reduce the number of early transfers off the inpatient rehabilitation unit.     

Adult spinal cord injury without radiological abnormality

Spinal cord injury without radiological abnormality is rare in adults. A case is described of a 61 year old man who fell 15 feet from a ladder striking his head on a wall who presented with neck pain and with motor and sensory neurological abnormalities in his limbs. Plain radiographs of the neck revealed no fractures or dislocations. Further imaging with computed tomography and magnetic resonance imaging revealed an osteophyte fracture with associated cord contusion at the C5 level. Careful neurological examination is essential in all cases of potential spinal injury.     

Quadriplegia from spinal cord injury in muscular dystrophy

Recommendations for exercise programs in patients with muscular dystrophy are controversial. These programs are designed to keep a patient ambulatory or functional for as long as possible. There have been no reports of a patient with muscular dystrophy who incurred a spinal cord injury. This report details the course of recovery and rehabilitation of a man with facioscapulohumeral muscular dystrophy with quadriplegia from a traumatic spinal cord injury. The patient was admitted to a spinal cord injury unit. After prolonged bedrest, he participated in physical and occupational therapy that was designed to exercise him just short of fatigue. Except for one incident, when the patient reinjured his spinal cord, he did not lose function that he had already attained. The rehabilitation of this patient demonstrates that it is possible for a patient with facioscapulohumeral muscular dystrophy who sustains a traumatic quadriplegia to enter a rehabilitation program with expectations for a good outcome despite a double disability.     

Association of antidepressant medication therapy with inpatient rehabilitation outcomes for stroke, traumatic brain injury, or traumatic spinal cord injury

Weeks DL, Greer CL, Bray BS, Schwartz CR, White JR Jr. Association of antidepressant medication therapy with inpatient rehabilitation outcomes for stroke, traumatic brain injury, or traumatic spinal cord injury.

Objective

To study whether outcomes in patients who have undergone inpatient rehabilitation for stroke, traumatic brain injury (TBI), or traumatic spinal cord injury (TSCI) differ based on antidepressant medication (ADM) use.

Design

Retrospective cohort study of 867 electronic medical records of patients receiving inpatient rehabilitation for stroke, TBI, or TSCI. Four cohorts were formed within each rehabilitation condition: patients with no history of ADM use and no indication of history of depression; patients with no history of ADM use but with a secondary diagnostic code for a depressive illness; patients with a history of ADM use prior to and during inpatient rehabilitation; and patients who began ADM therapy in inpatient rehabilitation.

Setting

Freestanding inpatient rehabilitation facility (IRF).

Participants

Patients diagnosed with stroke (n=625), TBI (n=175), and TSCI (n=67).

Interventions

Not applicable.

Main Outcome Measures

FIM, rehabilitation length of stay (LOS), deviation between actual LOS and expected LOS, and functional gain per day.

Results

In each impairment condition, patients initiating ADM therapy in inpatient rehabilitation had longer LOS than patients in the same impairment condition on ADM at IRF admission, and had significantly longer LOS than patients with no history of ADM use and no diagnosis of depression (P<.05). LOS for patients initiating ADM therapy as inpatients even exceeded LOS for patients without ADM history, but who had a diagnosis for a depressive disorder. Deviation in LOS was significantly larger in the stroke and TBI groups initiating ADM in IRF than their counterparts with no history of ADM use, illustrating that the group initiating ADM therapy in rehabilitation significantly exceeded expected LOS. Increased LOS did not translate into functional gains, and in fact, functional gain per day was lower in the group initiating ADM therapy in IRF.

Conclusions

Explanations for unexpectedly long LOS in patients initiating ADM in inpatient rehabilitation focus on the potential for ADM to inhibit therapy-driven remodeling of the nervous system when initiated close in time to nervous system injury, or the possibility that untreated sequelae (eg, depressive symptoms or fatigue) were limiting progress in therapy, which triggered ADM treatment.     

The importance of verifying diagnosis in patients with spinal cord injury hospitalized in a rehabilitation department

Background. According to Annex 7 to Resolution no. 226/2003, the National Health Fund does not cover the costs of diagnostic procedures performed in rehabilitation departments. Everyday clinical practice shows that the availability of imaging studies and specialized laboratory tests is often crucial for effective and safe patient management. The purpose of our research was to analyze the need for diagnostic procedures and verification of referral diagnosis in patients with spinal cord injury admitted to a rehabilitation department. Material and methods. We studied 175 patients (134 males and 41 females, 16 to 75 years of age, mean age 35.2 years) admitted with a diagnosis of spinal cord injury to the Rehabilitation Department of the Warsaw Medical University in the period from 1998 to 2004. Referral diagnoses were compared to the diagnoses established after examination on admission to our Department (verified diagnoses). Results. In 67 patients (38.3%) the referral diagnosis differed from the verified diagnosis. The most frequent new diagnoses included: myositis ossificans: 22 cases (12.6%), decubitus ulcers: 14 cases (8.0%); other trophic skin lesions: 9 cases (5.4%) and undiagnosed concomitant injuries: 5 cases (2.9%). 13 patients (7.5%) were disqualified from further rehabilitation and referred for surgical treatment. Conclusions. 38.3% of our patients with spinal cord injury admitted for rehabilitation had an incorrect referral diagnosis. Legislative decisions limiting the availability of diagnostic procedures at rehabilitation departments lead to decreased health care quality. Spinal cord injury patients admitted for rehabilitation require verification of the referral diagnoses, preferably by the staff of the rehabilitation department.     

Delay in Spinal Cord Injury Diagnosis Due to Sedation: A Case Report

Background

In the United States, the incidence of traumatic spinal cord injury is estimated to be approximately 40 per one million persons per year. The most common causes of traumatic spinal cord injury are motor vehicle collisions, falls, gunshot wounds, and sports accidents.

Objective

To report signs, symptoms, clinical presentation, diagnostic modalities, acute management, and treatment of an acute spinal cord injury.

Case Report

A case of traumatic cervical spine injury that was not immediately apparent upon presentation is reported. Diagnostic confirmation was possible after obtaining magnetic resonance imaging and after the sedative effects of medications resolved, allowing for a better physical examination.

Conclusion

Neurogenic shock should be considered in patients with hypotension of unknown or unclear etiology. A ground-level fall is sufficient to cause traumatic spinal cord injury in elderly patients, and a cervical spine computed tomography scan without clear fracture does not exclude this pathology.     

Spinal cord injury and concomitant traumatic brain injury. Results of a longitudinal investigation

One-hundred fifty persons with traumatic onset spinal cord injury (SCI) were administered a comprehensive neuropsychologic test battery an average of 7 weeks after SCI, and 67 were retested using the same battery an average of 38 weeks after initial testing. It was hypothesized that if traumatic brain injury were a significant sequela of SCI, retesting would reveal evidence of cognitive recovery over time and would further enable a clearer separation of preinjury cognitive capacity from the effects of injury. Significant improvement in test performance occurred across time to the degree and in a pattern similar to that noted in persons who have sustained mild to moderate traumatic brain injury. Hypothesized relationships between level and extent of SCI, etiology of injury and presence/absence of loss of consciousness and neuropsychologic test scores were not observed. Implications for the rehabilitation process are discussed.     

Neoplastic versus traumatic spinal cord injury: an outcome comparison after inpatient rehabilitation.

OBJECTIVE: To compare outcomes of patients with neoplastic spinal cord compression (SCC) to outcomes of patients with traumatic spinal cord injury (SCI) after inpatient rehabilitation. DESIGN: A comparison between patients with a diagnosis of neoplastic SCC admitted to an SCI rehabilitation unit and patients with a diagnosis of traumatic SCI admitted to the regional Model Spinal Cord Injury Centers over a 5-year period, controlling for age, neurologic level of injury, and American Spinal Injury Association impairment classification. SETTING: Tertiary university medical centers. PATIENTS: Twenty-nine patients with neoplastic SCC and 29 patients with SCI of traumatic etiology who met standard rehabilitation admission criteria. MAIN OUTCOME MEASURES: Acute and rehabilitation hospital length of stay (LOS), Functional Independence Measure (FIM) scores, FIM change, FIM efficiency, and discharge rates to home. RESULTS: Patients with neoplastic SCC had a significantly (p < .01) shorter rehabilitation LOS than those with traumatic SCI (25.17 vs 57.46 days). No statistical significance was found in acute care LOS. Motor FIM scores on admission were higher in the neoplastic group, but discharge FIM scores and FIM change were significantly lower. Both groups had similar FIM efficiencies and community discharges. CONCLUSIONS: Patients with neoplastic SCC can achieve rates of functional gain comparable to those of their counterparts with traumatic SCI. While patients with traumatic SCI achieve greater functional improvement, patients with neoplastic SCC have a shorter rehabilitation LOS and can achieve comparable success with discharge to the community.     

扩散张量成像在急性脊髓损伤中的研究进展

脊髓是中枢神经系统的重要组成部分,不同时期、不同程度的脊髓损伤造成的后果及预后也不同,急性脊髓损伤病情发展迅速且较为严重。常规磁共振成像(magnetic resonance imaging,MRI)上的信号变化对于临床评估具有一定的局限性,磁共振扩散加权成像(diffusion weighted imaging,DWI)和磁共振扩散张量成像(diffusion tensor imaging,DTI)通过测量水分子的扩散运动,从微观上反映脊髓的损伤情况,不仅能早期及时地判断出急性脊髓损伤,而且能定量分析白质纤维束损伤的严重程度,为临床对这类患者的干预提供一定的价值信息。本文简要介绍了磁共振扩散加权成像和磁共振扩散张量成像技术在急性脊髓损伤中的应用情况及研究进展。     

Position statement: definition of traumatic brain injury

Menon DK, Schwab K, Wright DW, Maas AI, on behalf of The Demographics and Clinical Assessment Working Group of the International and Interagency Initiative toward Common Data Elements for Research on Traumatic Brain Injury and Psychological Health. Position statement: definition of traumatic brain injury.A clear, concise definition of traumatic brain injury (TBI) is fundamental for reporting, comparison, and interpretation of studies on TBI. Changing epidemiologic patterns, an increasing recognition of significance of mild TBI, and a better understanding of the subtler neurocognitive neuroaffective deficits that may result from these injuries make this need even more critical. The Demographics and Clinical Assessment Working Group of the International and Interagency Initiative toward Common Data Elements for Research on Traumatic Brain Injury and Psychological Health has therefore formed an expert group that proposes the following definition:

TBI is defined as an alteration in brain function, or other evidence of brain pathology, caused by an external force.

In this article, we discuss criteria for considering or establishing a diagnosis of TBI, with a particular focus on the problems how a diagnosis of TBI can be made when patients present late after injury and how mild TBI may be differentiated from non-TBI causes with similar symptoms. Technologic advances in magnetic resonance imaging and the development of biomarkers offer potential for improving diagnostic accuracy in these situations.     

Differential recovery of behavioral status and brain function assessed with functional magnetic resonance imaging after mild traumatic brain injury in the rat

OBJECTIVE: The relationship between cerebral integrity, recovery of brain function, and neurologic status after mild traumatic brain injury is incompletely characterized. DESIGN: Prospective and randomized study in rodents. SETTING: University laboratory. SUBJECTS: Male Wistar rats (290-310 g). INTERVENTIONS: In rats, quantitative diffusion weighted imaging (DWI), perfusion weighted imaging (PWI), T2-weighted imaging (T2WI), and functional magnetic resonance imaging (fMRI) were performed up to 21 days after weight-induced, closed-head, mild traumatic brain injury (MTBI, n = 6) or sham operation (n = 6). Pixel-by-pixel analysis and region of interest analysis were used to evaluate structural (apparent diffusion coefficient [ADC] and basal cerebral blood flow [bCBF]) and functional magnetic resonance signal changes within the brain, respectively. Quantitative fMRI signal changes were correlated with behavioral measures. MEASUREMENTS AND MAIN RESULTS: Despite normal appearing DWI and T2WI findings following MTBI, persistent hypoperfusion developed that was not associated with cytotoxic edema. In contrast, the ADC was significantly increased by approximately 5% at 1 and 7 days post-MTBI. Post-MTBI fMRI responses to hypercapnia and forepaw stimulation were significantly impaired and showed a differential recovery rate between and within investigated region of interests. Significant dysfunction in forepaw placement test persisted up to day 1 and correlated significantly with fMRI signal changes in the primary somatosensory and motor cortices. CONCLUSIONS: MTBI produced distinct changes on multimodal MRI and behavioral variables acutely and chronically. Following MTBI, fMRI and ADC-bCBF pixel-by-pixel analysis identified subtle structural and functional alterations in the brain that appeared completely normal on conventional DWI and T2WI after concussion injury. The former techniques may therefore provide great potential for understanding mild traumatic brain injury, identifying mechanisms underlying recovery, and investigating specific interventions to enhance functional outcome.     

陈旧性颈髓损伤的MRI改变及意义

对24例陈旧性颈髓损伤患者进行MRI检查,并对其中23例采取了手术治疗。通过对颈髓损伤的MRI影像和手术治疗结果分析,探讨了陈旧性颈髓损伤的MRI改变及其意义。结果表明,MRI可显示陈旧性颈髓损伤的部位和程度,其改变与脊髓损伤的病理变化一致,对治疗方法选择和预后判断具有重要意义。     

综合康复治疗对创伤性脊髓损伤后肌痉挛的影响

目的观察颈、胸段创伤性脊髓损伤后肌痉挛患者综合康复治疗疗效及病程对康复疗效的影响.方法根据其病程将30例颈、胸段创伤性脊髓损伤后肌痉挛患者分为早期组和晚期组,并分别给予运动治疗、热疗及气压式四肢血液循环促进装置等综合康复治疗,治疗前、后采用改良的Ashworth痉挛评分法(Modified Ashworth Scale,MAS)评定.结果两组患者治疗前、后MAS评分差异均有显著性意义(t=16.170,P＜0.000 1;t=6.00,P＜0.000 1),并且早期组疗效优于晚期组(t=-5.014,P＜0.01).结论对于创伤性脊髓损伤后肌痉挛应尽早采取综合康复治疗.     

骨髓间充质干细胞立体定向移植联合亚低温治疗大鼠脑损伤

背景:临床研究证明,亚低温(33~35℃)能有效减轻继发性脑和脊髓损伤,对中枢神经损伤有确切的保护作用。目的:检测是否可以通亚低温治疗的方法提高骨髓间充质干细胞立体定向移植对重型颅脑损伤大鼠的治疗效果。方法:采用液压颅脑损伤仪,给予Wistar大鼠2.53.31~303.98kPa液压冲击力,制成重型液压颅脑损伤大鼠模型,将其随机分为脑损伤组,骨髓间充质干细胞移植组,亚低温+骨髓间充质干细胞组。后2组伤后6h将体外培养的SD大鼠骨髓间充质干细胞立体定向移植到脑损伤灶内,亚低温+骨髓间充质干细胞组同时给予低温治疗。伤后第3天用WesternBlot检测脑组织中AQP4蛋白合成的变化,采用干湿比重法测脑组织含水量。伤后24h,3d及伤后1,2周行动物神经学缺损评分,2周后处死行免疫组织化学和苏木精-伊红染色。结果与结论:亚低温治疗后,与脑损伤组和骨髓间充质干细胞移植组相比,亚低温+骨髓间充质干细胞组AQP4蛋白表达量及脑水肿程度也明显降低(P<0.05),移植后1和2周,亚低温+骨髓间充质干细胞组的大鼠神经学缺损评分明显低于其他两组;且其脑组织切片中的神经元数量较其他两组明显增多(P<0.01)。提示骨髓间充质干细胞立体定向移植联合亚低温治疗大鼠脑损伤可明显改善重型颅脑损伤后大鼠的神经学功能。