唑吡坦对脑损伤植物状态患者促醒疗效的观察

目的 观察非常规促醒药物唑吡坦对脑损伤昏迷植物状态患者的促醒作用,分析该作用是否存在干预时间相关性. 方法 采用单光子发射型计算机体层摄影技术观察7例服用唑吡坦的持续性植物状态患者服药0.5 h前后及1周后99Tcm-双半光乙酯(ECD)脑灌注显像.做可视化分析;应用脑状态监测仪(CSM)进行检测,对比用药前后脑状态指数、肌电指数、爆发抑制指数的变化;观察患者临床指标变化,包括语言功能、肢体运动功能、肌张力、睡眠质量等的变化. 结果 (1)患者服药后脑状态指数、肌电指数均高于服药前爆发抑制指数低于用药前,差异均有统计学意义(P<0.05).(2)服药后7例患者脑损害区血流较服药前明显增加.(3)7例患者中3例成功促醒,表现为服药后0.5 h能与家人及医生进行简单的交流,用药后第2天便能做简单的数学运算,下肢可遵嘱做屈曲运动.其中1例原有的肢体震颤及扭转痉挛明显缓解:余4例肌张力及睡眠质量改善. 结论 唑吡坦能恢复部分脑损害持续性植物状态患者的脑功能,脑功能的改善与服药时间长短无关,脑功能的改善是"一步到位"而非"逐步改善".     

Functional imaging of vegetative state applying single photon emission tomography and positron emission tomography

Nuclear medicine techniques, such as single photon emission tomography (SPECT) and positron emission tomography (PET) have been applied in patients in a vegetative state to investigate brain function in a non-invasive manner. Parameters investigated include glucose metabolism, perfusion at rest, variations of regional perfusion after stimulation, and benzodiazepine receptor density. Compared to controls, patients in a vegetative state show a substantial reduction of glucose metabolism and perfusion. While patients post-anoxia exhibit a rather homogenous cortical reduction of glucose metabolism, patients after head trauma often show severe cortical and sub-cortical reductions at the site of primary trauma. To distinguish reduced glucose metabolism due to neuronal inactivation from neuronal loss, flumazenil-PET, an indicator of benzodiazepine receptor density, could add valuable information on the extent of brain damage. Activation studies focus on the evaluation of residual brain network, looking for processing in secondary projection fields. So far the predictive strength concerning possible recovery for the individual patient is limited, and PET and SPECT are not routine procedures in the assessment of patients in a vegetative state.     

Effects of fluoxetine on regional cerebral blood flow in obsessive-compulsive patients

Six drug-free obsessive-compulsive patients were given single photon emission computerized tomography scans before and during treatment with fluoxetine. The treatment significantly reduced the patients' "hyperfrontality," as determined by the ratio between medial-frontal and whole cerebral cortex blood flow, and significantly lowered ratings of obsessive-compulsive and anxiety symptoms.     

Multi‐modal brain imaging showing brain damage to the orbitofrontal cortex and left hemisphere,in a case of prolonged hypoglycemia‐induced transient hemiplegia followed by persistent encephalopathy

A 21‐year‐old left‐handed male patient was admitted with a 19‐h history of coma after substantial insulin injection for suicide attempt. Although the patient recovered from coma 3 days after injury, he experienced transient hemiplegia followed by permanent brain damage. Electroencephalogram (EEG), brain magnetic resonance imaging (MRI), and brain single‐photon emission computed tomography (SPECT) identified the localization of this dysfunction, but consistency between clinical symptoms and brain images changed depending on the course of treatment. Transient hemiplegia corresponded to abnormal waveforms on EEG and decreased cerebral blood flow on SPECT, whereas persistent dysfunctions corresponded to abnormal brain regions on MRI and SPECT.     

Crossed cerebellar diaschisis demonstrated by SPECT in hemiplegic children

Crossed cerebellar diaschisis (CCD) in twenty five children with hemiplegia were studied using single photon emission computed tomography (SPECT) with N-isopropyl-p-I-123-iodoamphetamine. Seven of twenty-five patients had cerebral palsy, and the others were impaired by acquired brain injury between ten months and fourteen years of age. CCD was demonstrated in five patients (20%), who were impaired by acquired brain injury after seven years of age. CCD could never be detected in patients with cerebral palsy. Ipsilateral cerebellar diaschisis was also demonstrated in two patients with cerebral palsy and three with early acquired brain injury before three years of age. It is suggested that diaschisis presents itself as a different form in a contralateral and ipsilateral cerebellum before three years of age from a form which presents after seven years of age.     

Left prefrontal glucose hypometabolism in the depressed state: a confirmation

The resting-state cerebral metabolic rates for glucose of 10 severely depressed patients (seven bipolar and three unipolar) were compared, before and after treatment with tricyclic antidepressants, to those of 10 control subjects of similar age by means of positron emission tomography and the fluorodeoxyglucose method. Significant left-right prefrontal asymmetry was present in the patients before but not after successful treatment, suggesting that medication can reduce this asymmetry. Also, significant hypofrontality and whole-cortex hypometabolism were found in the patients in the depressed state and persisted in the treated state, despite clinical improvement, suggesting that these abnormalities are not state dependent.     

Thalamic proton magnetic resonance spectroscopy in vegetative state induced by traumatic brain injury

OBJECTIVES: To determine whether proton magnetic resonance spectroscopy (MRS), a newer radiographic technology, would be useful in the evaluation of the thalamus of patients in vegetative states resulting from traumatic brain injury. METHODS: 14 victims of severe traumatic brain injury who were in the vegetative state and whose magnetic resonance images of the thalamus were normal underwent bilateral thalamic proton (MRS) studies. The N-acetyl aspartate to creatine (NAA:Cr) and choline to creatine (Cho:Cr) ratios were obtained for each patient. The proton thalamic MRS findings of patients who were in a persistent vegetative state (n = 8) and in patients who had regained awareness after being in the vegetative state (n = 6) were compared with proton thalamic MRS findings in five healthy volunteers. RESULTS: While conventional magnetic resonance imaging suggested that each patient had a normal thalamus, proton MRS indicated that the thalamus of each patient in the series was damaged. The NAA:Cr ratio was significantly lower in the thalami of both the patients who remained in a persistent vegetative state for the duration of the study and in those who regained awareness after being in the vegetative state (p < 0.001). In addition, NAA:Cr ratios were lower in the group of patients who remained in a persistent vegetative state than in the group of patients who regained awareness after being in the vegetative state (p < 0.001). CONCLUSIONS: Results suggest that the NAA:Cr ratio within the thalamus is significant and that thalamic MRS may be helpful when attempting to determine the degree of severity of neuronal and axonal injury in patients in the vegetative state.     

高血压脑出血昏迷患者脑功能状态监测的临床研究

目的 探讨高血压脑出血后昏迷患者脑功能状态监测的应用及其对预后评估的作用. 方法 回顾性分析119例基底节区高血压脑出血后昏迷患者的临床资料及脑功能状态监测数据,根据随访3个月的预后情况将患者分为清醒、昏迷及死亡3组,比较各组患者在入院时、入院后第3天、第7天及第14天时脑状态指数(CSI)的差异性及变化情况. 结果 119例患者入院时的CSI值与GCS评分呈正相关关系(Spearman相关系数rp=0.816,P=0.000).各组患者发病后不同时间CSI值有差别,清醒组CSI值最高,昏迷组最低,统计分析显示各组患者在入院时、入院后第3天、第7天及第14天时CSI值差异均有统计学意义(P＜0.05). 结论 脑功能状态监测可以反映患者的脑功能状态水平,在临床上应用CSI值连续监测高血压脑出血后昏迷患者的脑功能状态有助于预后评估及指导诊治.     

Brain function in the vegetative state

Positron emission tomography (PET) techniques represent a useful tool to better understand the residual brain function in vegetative state patients. It has been shown that overall cerebral metabolic rates for glucose are massively reduced in this condition. However, the recovery of consciousness from vegetative state is not always associated with substantial changes in global metabolism. This finding led us to hypothesize that some vegetative patients are unconscious not just because of a global loss of neuronal function, but rather due to an altered activity in some critical brain regions and to the abolished functional connections between them. We used voxel-based Statistical Parametric Mapping (SPM) approaches to characterize the functional neuroanatomy of the vegetative state. The most dysfunctional brain regions were bilateral frontal and parieto-temporal associative cortices. Despite the metabolic impairment, external stimulation still induced a significant neuronal activation (i.e., change in blood flow) in vegetative patients as shown by both auditory click stimuli and noxious somatosensory stimuli. However, this activation was limited to primary cortices and dissociated from higher-order associative cortices, thought to be necessary for conscious perception. Finally, we demonstrated that vegetative patients have impaired functional connections between distant cortical areas and between the thalami and the cortex and, more importantly, that recovery of consciousness is paralleled by a restoration of this cortico-thalamo-cortical interaction.     

Effect of ECT on Cerebral Blood Flow in Melancholia Assessed with SPECT

Ten endogenously depressed patients were studied before, during, and after electroconvulsive therapy. The nature and severity of depression was measured using the Newcastle Rating and Hamilton Depression Scales. The mean number of treatments administered was 12, and all patients recovered. Regional cerebral blood flow was studied using single photon emission computerized tomography (SPECT) with inhalation of (133)Xe. The mean values dropped by 8% after session three and a further 13% after the last session. The flow values of untreated patients was significantly higher than those found in 10 healthy volunteers. The values in patients following the last treatment session did not differ from those in the control group. There were no changes in the regional distribution of blood flow between controls and among patients in the three situations studied. No correlation was found between the physiological data and single items from the rating scales used. Increased cerebral blood flow values found in the treatment situation are due to the presence of depressive illness as such and not to agitation or anxiety. The parallel between flow data and clinical data points to the normalization taking place after, and not during, electroconvulsive therapy.     

A case of primary brain-stem injury recovered from persistent vegetative state after L-dopa administration]

A 51-year-old male was transferred to our hospital just after traffic accident. On admission, the patient was comatose (Glasgow Coma Scale of 6) and showed a left hemiparesis with a left oculomotor nerve palsy. Computed tomography demonstrated a traumatic subarachnoid hemorrhage without mass lesion. Magnetic resonance imaging showed high intensity lesions on the left dorsolateral midbrain and the right cerebral peduncle. The distribution of lesions implied diffuse axonal injury involving dopaminergic systems such as the substantia nigra and the ventral tegmental area. After several months of conservative management, the patient showed no recovery and was diagnosed as persistent vegetable state. The administration of L-dopa was then started and the patient showed remarkable neurological improvement. Therefore the patient's neurological status was thought to be modified with primary brain stem injury and accompanying traumatic Parkinson's syndrome. It is important to understand "pseudo" persistent vegetative state in the management of patients showing prolonged consciousness disturbance. L-dopa should be considered as the drugs of pharmacological intervention for the patients of masked parkinsonism behind "pseudo" persistent vegetative state whose dopaminergic systems might have been damaged.     

CEREBRAL CHANGES IN OLD AGE DEPRESSION: A CASE REPORT WITH FINDINGS ON SINGLE PHOTON EMISSION TOMOGRAPHY

An 82-year-old woman with no past psychiatric history developed a depressive illness from which she recovered within 2 months of initiating antidepressant therapy. She underwent single photon emission computerized tomography (SPET) when depressed and subsequently 3 and 8 months after complete clinical recovery. Impaired cerebral perfusion evident during the depressed phase improved with clinical recovery, suggesting that the impaired perfusion accompanying the depressed state is partly a state dependent abnormality. However, the possibility of persistence of such impairment beyond clinical recovery cannot be ruled out.     

Regional cerebral blood flow in childhood autism: a SPECT study.

OBJECTIVE: The authors investigated a possible cortical brain dysfunction associated with infantile autism. METHOD: They measured regional cerebral blood flow with single photon emission computed tomography (SPECT) and xenon-133 in 21 children with primary autism (according to DSM-III-R criteria). Five cortical brain areas including frontal, temporal, and sensory association cortices were examined in order to test the recent hypothesis of cerebral dysfunction in primary autism. Anatomical references for each subject were obtained with computerized tomography or magnetic resonance imaging and were used to delimit the regions of interest for SPECT analysis. RESULTS: When the results from the group with primary autism were compared with an age-matched group of nonautistic children with slight to moderate language disorders (N = 14), no cortical regional abnormalities were found. CONCLUSIONS: It appears that there is no regional cortical dysfunction in primary autism; however, in light of methodological limitations, one cannot exclude the possibility of more localized or subcortical brain dysfunctions in autism.     

标准外伤大骨瓣开颅术在重型颅脑损伤中的应用

目的探讨标准外伤大骨瓣开颅减压术治疗重型颅脑损伤的效果。方法63例重型颅脑损伤患者随机分为2组:标准外伤大骨瓣组(治疗组)32例,常规骨瓣组(对照组)31例。全部病例术前均扫描证实颅内损伤情况,术后治疗方案基本相同。术后6个月临床随访进行格拉斯哥预后标准(GOS)评定。结果治疗组32例中,恢复良好15例,中残6例,重残2例,植物生存1例,死亡8例。对照组31例中,恢复良好7例,中残5例,重残2例,植物生存2例,死亡15例(P<0.05)。结论标准外伤大骨瓣开颅减压术治疗急性单侧幕上血肿、脑挫裂伤及单侧大脑半球肿胀有较确切疗效。     

Cerebral blood volume, endarterectomy and SPECT

Cerebral blood flow and cerebral blood volume were measured and quantified using single photon emission computed tomography before and after unilateral endarterectomy in 3 patients with bilateral severe lesions of the internal carotid artery. These parameters were measured using an intravenous injection of 133 Xenon and 99m Technetium respectively. Before endarterectomy cerebral blood volume was high in all patients suggesting a focal vasodilatation in response to a reduced cerebral perfusion pressure. After endarterectomy a decrease of cerebral blood volume and an increase of cerebral blood flow were observed. These preliminary results confirm that the hemodynamic adaptative mechanisms secondary to carotid occlusion are reversible when the stenosis is removed and demonstrate that these changes can be accurately measured using single photon emission computed tomography. Positron emission tomography was previously considered to be the only method able to quantify cerebral blood volume in man. Single photon emission computed tomography can also be considered a reliable technique to measure both cerebral blood flow and cerebral blood volume. This technique can then be used to assess individual cerebral vascular adaptative states and to evaluate the influence of cerebral hemodynamic changes on stroke occurrence in large longitudinal studies.     

The effects of antipsychotic treatment on cerebral structure and function in schizophrenia

This paper analyses the effects of antipsychotic drug treatment on cerebral structure and function in schizophrenia reviewing qualitatively some of the relevant literature on the issue. Magnetic resonance imaging (MRI) studies of brain morphology in patients at different stages of illness and after varying times of neuroleptic exposure and longitudinal studies show possible different effects of first and second generation antipsychotics. This is true also for functional parameters, such as regional cerebral blood flow and metabolism, analysed, both in resting condition and after specific activation paradigms, with such diverse techniques as positron emission tomography (PET), single photon emission computed tomography (SPECT), functional MRI and MR spectroscopy. The possible molecular mechanisms underlying such differences and whether they represent direct drug effects or indirect consequences of their different and specific interactions with the ‘natural’ pathophysiological trajectory of brain abnormalities in schizophrenia are matter of present research and debate.     

Evaluation of the effects of total sleep deprivation on cerebral blood flow using single photon emission computerized tomography.

HMPAO-single photon emission computerized tomography (SPECT) is a useful technique in studying cerebral blood flow (CBF). This method is suitable to evaluate the differences of CBF with reference to total sleep deprivation (TSD) within 24 h because of the short half-life of the radiopharmaceutical compound. In the present study, CBF before and after TSD was analysed in patients suffering from major depression. The morning before and after TSD, Tc-HMPAO-SPECT was performed in 20 patients. Hamilton Rating Scale for Depression scores and subjective ratings were obtained daily. Eleven patients responded to TSD; 9 were nonresponders. The main finding was a significant left temporal and mainly right parietal increase of CBF, which was observed in the responders only. CBF values and the severity of depression correlated inversely.     

Technetium-99m HM-PAO single photon emission computed tomography imaging in transient global amnesia.

Five right-handed patients with pure transient global amnesia were evaluated with technetium-99m hexamethylpropyleneamine oxime single photon emission computed tomography after the amnesic attack. Independent of the interval between the procedure and the amnesic episode, single photon emission computed tomography demonstrated a decreased cerebral blood flow in the left temporal lobe in one patient and in the left parietotemporal region in three patients, with a more marked reduction in the temporal lobe. The remaining three patients were normal. A control single photon emission computed tomographic study was carried out in one patient 3 months after the amnesic attack and showed a left-sided persistent temporal hypoperfusion. These findings suggest that in some patients, transient global amnesia can be due to a vascular mechanism requiring strong investigations for vascular risk factors and appropriate treatment. During a follow-up period of 12 to 32 months, none of the patients with regional hypoperfusion suffered cerebrovascular events, suggesting that single photon emission computed tomography has no predictive value for further stroke.     

Battered child syndrome: cerebral ultrasound and CT findings after vigorous shaking.

Child abuse by whiplash-shaking can lead to severe cerebral damage, neurological defects and mental retardation. Cerebral damage has been found with and without external evidence of head injury. We report the sonographic findings in two children after traumatization due to repetitive vigorous whiplash shaking. Cerebral sonography revealed cerebral edema at admission or within 48 hours thereafter. Follow-up studies demonstrated development of marked brain atrophy in both cases. The sonographic findings were confirmed by cranial computerized tomography. Doppler sonography was used to monitor cerebral perfusion by measuring intracranial blood flow. The clinical history of the patients demonstrates that cerebral sonography in combination with Doppler sonography not only serves as a diagnostic tool but also allows adjustment of therapy to the actual clinical status of the patient.     

Single photon emission computerized tomography during and between seizures

Summary In three patients, patterns of brain activity were measured by ^99mTc-hexamethyl-propyleneamineoxime (^99mTc-HM-PAO) brain SPECT (single photon emission computerized tomography) in ictal and interictal states. Increased relative blood flow indicated the focus of partial seizures, its spreading to adjacent cortical regions and to distant brain structures via neuronal pathways. Ictal patterns of regional cerebral blood flow (rCBF) were in agreement with clinical symptomatology. Successive SPECT studies were performed after 3–7 days in the absence of electroencephalographic and clinical signs of seizures but still revealed increased relative blood flow in the focus of the seizures. SPECT studies, performed 2–6 weeks after the last clinically observable seizures, demonstrated the transition from increased to decreased relative blood flow in the focus of the seizures. In one patient, the EEG was complementary to and corresponded with the rCBF patterns in the ictal state. However, the dynamics of interictal changes could only be assessed by brain SPECT.