ObjectiveMalingering of neuropsychological damage is common among traumatic brain injury patients pursuing disability compensation in forensic contexts. There is an urgent need to explore differences in neuropsychological assessment outcomes with different levels of cooperation.MethodsA total of 420 participants with severe traumatic brain injury were classified into malingering group, partial cooperation group, and complete cooperation group according to the Binomial forced-choice digit memory test. The Wechsler Adult Intelligence Scale, event-related potential component, and Symptom Checklist 90 were applied subsequently to assess the psychological status of participants.ResultsParticipants in the malingering group presented lower scores in the binomial forced-choice digit memory test and the Wechsler Adult Intelligence Scale, lower P3 amplitude, and simultaneously higher scores in the Symptom Checklist 90 than the other two groups. The actual intelligence quotient of participants with malingering tendencies ranged mostly between normal and marginal damage, and they often reported elevated whole scale scores in the Symptom Checklist 90. The Cooperation Index (defined as the ratio of positive symptom distress index to global severity index, CI) was proposed and validated to function as an embedded validity indicator of the Symptom Checklist 90, and the area under the receiver operating characteristic (ROC) curve was 0.938. When valued at 1.28, CI has the highest classification ability in differentiating malingering from non-malingering. Combined with the CI and P3 amplitude, the area under the ROC curve for malingering diagnosis further reached 0.952.ConclusionAny non-optimal effort in a forensic context will lead to unexpected deviation in psychology evaluation results. CI is a potential candidate to act as an embedded validity indicator of the Symptom Checklist 90. The combination of CI and P3 amplitude can help to identify malingering in participants after severe traumatic brain injury.

目的 通过探索创伤性脑损伤(TBI)伤者智商值(IQ)与听觉P300的相关性,寻找能够反映伤者真实智能状态的评价指标.方法 征集需进行智能损害司法鉴定的TBI伤者,进行二项必选数字记忆测验,选取测验合作者427名,分别进行流行病学统计、中国修订韦氏成人智力量表(WAIS-RC)和P300检测,分析IQ与被试者基本情况及P300各成分之间的相关性.结果 年龄、受教育程度及TBI的严重程度对被试者的智能状态均有一定程度的影响;智能损害程度越严重,TBI伤者的P3波潜伏期和N2波潜伏期越长(P<0.01),IQ和P3波潜伏期之间呈显著负相关(r=-0.71,P<0.01),IQ和N2波潜伏期之间表现出弱负相关(r=-0.32,P<0.01).结论 P3波潜伏期比N2波潜伏期更能代表TBI伤者的真实智能水平,可作为评估脑外伤后智能损害的重要参考指标.

1 案例资料 案例1 女,62岁,既往体健,因"交通事故致颅脑损伤4小时"入院.查体:神志尚清,颈强二指.CT示双侧额叶挫伤并血肿,双侧额颞部硬膜下、外血肿,蛛网膜下腔出血,枕骨骨折.伤后8小时昏迷,急行开颅血肿清除、去骨瓣减压术.伤后第3天因左额叶血肿增多,再次行颅内血肿清除术.术后一月余出现小便功能障碍,表现为有时遗尿、不知漏尿发生,对尿意控制能力差,伴尿急、急迫性尿失禁.伤后6月复查CT示双额叶片状脑软化灶(左侧为重).查体:右上肢肌力IV级.伤后13月鉴定时对答切题,情绪欠稳定,四肢肌力、肌张力正常,仍有小便失禁.尿沉渣及化学分析:细胞(-),蛋白:阴性,比重:1.026,结晶(+),真菌:阴性,管型:阴性;尿流动力学检查:OAB(膀胱过度活动症)并急迫性尿失禁,膀胱收缩力正常,残余尿20mL,一周后复查残余尿36mL;造影检查无下尿路梗阻;精神测评:IQ为75,存轻度认知损害及人格改变.鉴定意见:精神障碍依据《人体损伤致残程度分级》[1]第5.10.1.1)款,评为十级伤残;颅脑损伤已行开颅术依据上述标准第5.10.1.8)款,评为十级伤残;轻度排尿功能障碍依据上述标准第5.9.1.9)款及B.11.b)款规定,评为九级伤残.

Rationale: Metallic mercury poisoning through intravenous injection is rare, especially for a homicide attempt. Diagnosis and treatment of the disease are challenging. Patient concerns: A 34-year-old male presented with pyrexia, chill, fatigue, body aches, and pain of the dorsal aspect of right foot. Another case is that of a 29-year-old male who committed suicide by injecting himself metallic mercury 15 g intravenously and presented with dizzy, dyspnea, fatigue, sweatiness, and waist soreness. Diagnosis: The patient's condition in case 1 was deteriorated after initial treatment. Imaging studies revealed multiple high-density spots throughout the body especially in the lungs. On further questioning, the patient's girlfriend acknowledged that she injected him about 40 g mercury intravenously 11 days ago. The diagnosis was then confirmed with a urinary mercury concentration of 4828 mg/L. Interventions: Surgical excision, continuous blood purification, plasma exchange, alveolar lavage, and chelation were performed successively in case 1. Blood irrigation and chelation therapy were performed in case 2. Outcomes: The laboratory test results and organ function of the patient in case 1 gradually returned to normal. However, in case 2, the patient's dyspnea was getting worse and he finally died due to toxic encephalopathy and respiratory failure. Lessons: Early diagnosis and appropriate treatment are critical for intravenous mercury poisoning. It should be concerned about the combined use of chelation agents and other treatments, such as surgical excision, hemodialysis and plasma exchange in clinical settings.