Early somatosensory evoked potentials in ischemic cerebrovascular diseases--I: Methodology, patients, normal group and review of the literature

Somatosensory evoked potentials (SEP) were examined in 140 patients suffering from cerebro-vascular ischemic disease. Patients were classified in 1. asymptomatic stenosis/occlusion, 2. complicated migraine, 3. transient ischemic attacks (TIA), 4. reversible ischemic neurologic deficit (RIND), 5. completed stroke and 6. Multiinfarct-dementia. Normal SEP values were obtained from 26 age-correlated normal persons without a history of neurologic or psychiatric disease. The findings were correlated to clinical data, EEG, Single-Photon Emission and Transmission Computertomography (SPECT, TCT). SEP were done by stimulation of the median nerve. We evaluated central conduction time (CCT), amplitude ratio (AR) and number of phases (PHAS) of cortical potentials within 50 ms. Also quotient of amplitude ratio left stimulation side to right stimulation side (AR l/r) was calculated. EEG were recorded by 19 electrodes according to the 10-20 scheme, focal signs and diffuse changes were evaluated. In TCT the location of hypodense lesions was evaluated. SPECT was performed by application of J123 IMP and Tc99 HMPAO as a tracer. Focal decrease of tracer uptake compared to the compartment was evaluated. Results of animal experiments and clinical studies are discussed in respect of patients and methods.     

氙CT对缺血性脑血管病血管储备功能的研究

目的 评价合并有脑血管狭窄的缺血性脑血管病患者脑血管储备功能(CVR)的特点.方法 对20例有脑血管狭窄的缺血性脑血管病患者分别在静息状态和静脉注入乙酰唑胺(ACZ)后行氙CT脑血流灌注检查,定量测定ACZ负荷前后局部脑血流(rCBF),计算CVR.比较所有受试全脑、患侧与健侧大脑半球、责任血管供应区与健侧对应血管供应区的rCBF和CVR.结果 责任血管供应区与健侧对应区域rCBF和CVR:两者静息rCBF差异无统计学意义,责任血骨供应区CVR低于健侧对应区域[(5.9±24.3)%比(25.9±32.6)%,P＜0.05].结论 CVR下降是合并有脑血管狭窄缺血性卒中患者的重要特点.

Abstract：

Objective To evaluate the cerebrovascular reserve(CVR) in patients of ischemic stroke with cerebrovascular stenosis by Xenon-enhanced CT. Methods Twenty subjects of ischemic stroke with cerebrovascular stenosis were recruited. All subjects were examined by Xenon-enhanced CT before and after acetazolamide (ACZ) challenge test to quantitatively measure the regional cerebral blood flow (rCBF) and CVR. Results We compared the rCBF in the corresponding region supplied with stenosed artery (divided manually) with that in the region of normal side. There was no significant difference in resting rCBF but in CVR [ipsilateral side vs. normal side ( 5.9 ± 24. 3 ) % vs ( 25.9 ± 32. 6 ) % , P ＜ 0. 05]. Conclusion Impaired CVR is an important character of the patients with cerebrovascular stenosis suffered from ischemic stroke.     

Somatosensory evoked potentials in comatose patients: comparison with clinical findings, EEG and prognosis

21 comatose patients were examined by somatosensory evoked potentials (SSEP). The findings were correlated with the stage of brainstem herniation, the EEG and the outcome. We evaluated the early components of the SSEP (N10, N13, N14, P15, N20) in view of presence, latency and interpeak-latency of the potentials. In most cases the percentage of abnormal SSEP increased from caudal to rostral registration sites, but the potential P15 and N20 were equally abnormal. The progression of herniation correlated with increasing abnormality of the potentials. SSEP over the scalp (P15, N20) could not be registered in patients without any EEG-activity (isoelectric). Mean values of latencies and the interpeak-latencies were significantly prolonged in all cases with fatal outcome. Our findings suggest SSEP as a useful tool in the evaluation of brain-dysfunction in comatose patients.     

Value of early acoustic and somatosensory evoked potentials in monitoring and prognostic assessment of coma in barbiturate therapy--comparison with clinical aspects and EEG

25 comatose patients suffering from severe cerebral lesions of different etiology were examined during barbiturate-therapy by Glasgow-Pittsburg-Coma-Scoring-System (GPCS), EEG, somatosensory and brainstem acoustic evoked potentials. The findings were correlated in view of prognostic prediction and importance for monitoring. A modified form of the Glasgow-Outcome-Score (GOS; independent-survival, dependent-survival, dead) was used for evaluating the outcome. In case of an initial GPCS less than 10 points none of the patients survived, in case of GPCS greater than 10 points 11 out of 19 patients survived. The latter relation of survival was also found in patients with improving or impairing scores during the observation period. In case of initial burst-suppression pattern in the EEG 7 out of 11 patients survived, in case of diffuse abnormalities with or with-out additional focal signs - 4 out of 10 patients survived, but in the latter there was none with an outcome of independent survival. All patients with an isoelectric EEG died. In case of bilateral recording of scalp- SEP 7 out of 11 patients survived, in case of unilateral loss of scalp-EP 4 out of 8 patients survived, but in the latter cases none with an outcome of independence. All patients with initial bilateral failure of scalp-SSEP or loss during the observation period died. In case of bilateral registrable BAEP (wave I to V) 11 out of 17 patients survived. All patients with initial uni- or bilateral failure of those potentials or loss during the observation period died.(ABSTRACT TRUNCATED AT 250 WORDS)     

The temporomandibular joint in rheumatoid arthritis. Correlations between clinical and computed tomography features

Clinical and computed tomography (CT) examination of the temporomandibular joint (TMJ) was performed in 26 patients with rheumatoid arthritis (RA) and 26 control subjects. Each examination was scored. In the group with RA 61.2% had physical signs in the stomatognathic system compared to 42.3% in a control group (NS); 88.4% of the group with RA had erosive or cystic lesions of the TMJ compared to 57.6% of control subjects (p less than 0.05). The clinical dysfunction score did not correlate with the CT TMJ score in RA. It correlated with the number of slow acting antirheumatic drugs used, the rheumatoid factor titer and radiographic scores of the hands and cervical spine. In agreement with others, we believe that the only specific CT lesions of RA are erosions and cysts of the mandibular condyle, that there is no correlation between clinical and CT findings of TMJ in RA, and that the intensity of destructive lesions of TMJ on CT in RA is well correlated with the severity of the disease.     

Early somatosensory evoked potentials in ischemic diseases--II: Normal values and findings in asymptomatic vascular stenoses/occlusions, complicated migraine, transitory ischemic attacks, reversible ischemic neurologic deficit, complete stroke and multi-infarct dementia

Somatosensory evoked potentials (SEP) were investigated in 140 patients suffering from cerebro-vascular ischemic disease (CVD). Data were compared to age-correlated normal persons (n = 26; male 16, mean age 55.6 years SD 10.9). Patients with asymptomatic vascular diseases (n = 10; male 7, mean age 63.8 years SD 10.4) showed bilateral prolonged CCT (left side p less than 0.05). Patients with TIA (n = 44; male 21, 58.3 years SD 12.3), complicated migraine (n = 3, all female, 24, 40, 63 years) and RIND (n = 17; male 10, 56.5 years SD 16.8) showed no abnormalities of CCT and AR as compared to normals. Abnormalities of PHAS were only seen in patients with RIND of the right carotic supply. In patients suffering from completed stroke (n = 40; male 29, mean age 56.9 years SD 14.4) bilateral prolongation of CCT was seen in those with ischemia of the right carotic supply; those with ischemia of the left carotic supply showed a significant asymmetry of CCT and deviation of AR l/r. In two patients with infarction of the pons an increase of CCT and decrease of AR at the side of the lesion was found. Patients with MID (n = 27; male 20, 69.7 years SD 10.3) showed significant bilateral prolongation of CCT, increase of AR (at the side of stimulation) and deviation of AR l/r (1.63).     

SPECT imaging of the stomach: comparison with barostat,and effects of sex,age, body mass index,and fundoplication. Single photon emission computed tomography

BACKGROUND: Impaired gastric accommodation may lead to dyspeptic symptoms. A non-invasive method using single photon emission computed tomography (SPECT) has been developed to measure gastric volumes. AIMS AND METHODS: Our aims were: to assess the accuracy of SPECT with three dimensional image analysis to measure balloon volumes in vitro; to compare gastric barostat balloon volumes measured post-meal and post-distension with total gastric volumes measured simultaneously with SPECT; to present normal gastric volume data for healthy adults; and to compare SPECT data in health with symptomatic post-fundoplication patients. RESULTS: In vitro balloon volumes measured by SPECT were highly accurate (R(2)=0.99). When measured simultaneously by gastric barostat and SPECT, postprandial/fasting volume ratios (2.2 (0.12) (mean (SEM)) v 2.3 (0.15), respectively; p=0.6) and post-distension volume ratios (1.4 (0.1) v1.3 (0.1); p=0.2) were highly comparable. In females, postprandial gastric volumes (675 (14) v 744 (20) ml for males; p=0.004) and changes in gastric volumes (464 (14) ml v 521 (20) ml for males; p=0.01) measured by SPECT were significantly lower than in males. No effects of age or body mass index were noted. The postprandial/fasting gastric volume ratio by SPECT was lower in post-fundoplication patients (2.7 (0.2)) than in healthy controls (3.4 (0.1); p=0.003). CONCLUSIONS: SPECT provides a non-invasive estimate of the effect of a meal on total gastric volume that is comparable to changes in balloon volume observed with the gastric barostat. The SPECT technique is promising for investigation of gastric volumes in health and disease and the effects of pharmacological agents.     

Early auditory evoked potentials and clinical course parameters in Friedreich ataxia

The previously published reports of early auditory evoked potentials in collectives of Freidreich's ataxia show a discrepancy of the results. On the other side clinically and theoretically in this disease there are some interesting aspects. For example there is a decrease of amplitudes in patients suffering from a disturbance of discrimination as far as various sources of noise are concerned. The examined patients show pathological as well as normal results with a high degree of correlation in clinical criteria and the sum of amplitudes. All patients with slowered nerve conduction velocity showed pathological early auditory evoked potentials. More importance can be attributed to the early diagnostics in addition to the previously described differential diagnostic application of the early auditory evoked potentials.     

急性脑梗死患者体感诱发电位检测与临床相关性研究

目的探讨急性脑梗死患者体感诱发电位(SEP)变化特点与病情严重程度之间的相关性。方法 94例脑梗死患者于入院当天进行日常生活能力指数量表(BI)评分和改良爱丁堡斯堪的纳维亚(MESSS)评分,根据瘫痪程度进行分级,且于入院3 d内行SEP检查。结果异常SEP全部位于患侧,异常率为28.7%,5.3%异常SEP同时位于健侧;SEP异常与神经功能缺损呈正相关。中枢传导时间延长与瘫痪程度、MESSS评分及BI评分间无相关性。N20波形缺失或显示不清与肢体瘫痪程度、神经功能缺损严重程度呈正相关,与BI评分呈负相关。结论 SEP反映了急性脑梗死患者感觉及运动的功能状态。N20波形缺失或显示不清,具有重要的临床应用价值。     

Electromechanical mapping versus positron emission tomography and single photon emission computed tomography for the detection of myocardial viability in patients with ischemic cardiomyopathy

OBJECTIVES: We compared catheter-based electromechanical mapping (NOGA system, Biosense-Webster, Haifa, Israel) with positron emission tomography (PET) and single photon emission computed tomography (SPECT) for prediction of reversibly dysfunctional myocardium (RDM) and irreversibly dysfunctional myocardium (IDM) in patients with severe left ventricular dysfunction. Furthermore, we established the optimal discriminatory value of NOGA measurements for distinction between RDM and IDM. BACKGROUND: The NOGA system can detect viable myocardium but has not been used for prediction of post-revascularization contractile function in patients with ischemic cardiomyopathy. METHODS: Twenty patients (19 males, age [mean +/- SD] 60 +/- 16 years, ejection fraction [EF] 29 +/- 6%) underwent viability testing with NOGA and PET or SPECT before revascularization. Left ventricular function was studied at baseline and six months after revascularization. RESULTS: The EF increased to 34 +/- 13% at six months (p < 0.05 vs. baseline). The 58 RDM and 57 IDM regions differed with regard to unipolar voltage amplitude (UVA) (9.2 +/- 3.9 mV vs. 7.6 +/- 4.0 mV, p < 0.05), normalized UVA (106 +/- 54% vs. 75 +/- 39%, p < 0.05), and tracer uptake (76 +/- 17% vs. 60 +/- 20%, p < 0.05). The NOGA local shortening did not distinguish between RDM and IDM (6.4 +/- 5.8% vs. 5.4 +/- 6.6%). By receiver operating characteristic curve analysis, myocardial tracer uptake had better diagnostic performance than UVA (area under curve [AUC] +/- SE: 0.82 +/- 0.04 vs. 0.63 +/- 0.05, p < 0.05) and normalized UVA (AUC +/- SE: 0.70 +/- 0.05, p < 0.05). Optimal threshold was defined as the value yielding sensitivity = specificity for prediction of RDM. Sensitivity and specificity were 59% at a UVA of 8.4 mV, 65% at a normalized UVA of 83%, and 78% at a tracer uptake of 69%. CONCLUSIONS: The NOGA system may discriminate RDM from IDM with optimal discriminatory values for UVA and normalized UVA of 8.4 mV and 83%, respectively. However, the diagnostic performance does not reach the level obtained by PET and SPECT in patients with severe heart failure.     

Multimodal evoked potentials and heart rate variability in comatose patients. 2. Visual evoked potentials and computed tomographic findings

Visual evoked potentials (VEPs) were examined as an integrated parameter in a multimodal EP study of brain bioelectrical activity in 33 comatose patients (Glasgow Coma Score 3-6) after craniocerebral trauma. Recordings were performed not only from the occipital (01-02) but also from the central (Cz-C3, Cz-A1, Cz-C4) and frontal (F3-F4) areas. The results show an attenuation of the vertex VEP (SNR 3.2 +/- 1.7) and an increase in the occipital VEP (SNR 4.8 +/- 2.3) as compared to the control group (SNR vertex 7.0 +/- 3.0/SNR occipital 3.9 +/- 2.0). In addition, 16 of the comatose patients showed a very considerable loss of the normally polyphasic character of the occipital VEP in favour of a potential that looked almost monophasic; this was either left or right dominant, and was recorded as a negative or positive potential, respectively, in bipolar recording (01-02). Comparison of the electrophysiological and computer tomography findings showed a laterally correlated change in the occipital VEP: contralateral to the injured hemisphere, the VEP was dominant, ipsilateral it was reduced or extinguished.     

脑诱发电位与功能性脑成像在肠易激综合征研究中的应用

肠易激综合征(Irritablebowelsyndmme，IBS)是腹部不适或腹痛伴排便异常的一组肠功能障碍综合征，因其缺乏明显形态学及生化异常，病因及发病机制不甚清楚，给诊断及治疗带来了许多困难。近年来，IBS患者内脏感觉异常这一病理生理改变受到广泛关注，为深入了解内脏感觉异常的神经生物学机制，最近几种可客观评价IBS患者感觉传入通路及大脑信息处理过     

Cerebral monitoring with somatosensory evoked potentials in carotid surgery. A review of 141 carotids

OBJECTIVE: To evaluate postoperative and mid-term results of carotid surgery (CS) with somatosensory evoked potentials (SEP) monitoring. METHODS: Between 1998 and 2006, 141 CS in 124 patients were performed under general anesthesia. Selective shunting was based on SEP abnormality. Shunting criteria were: reduction up to 50% of the amplitude or latency increasing up to 10%. Early results and follow-up data are analyzed retrospectively. RESULTS: Shunting rate was 6%, 3 strokes (two transient strokes) occurred and one patient died of perioperative myocardial ischemia. The cumulative stroke and death rate at 30 days was 1.4%. CONCLUSIONS: Intra-operative SEP monitoring with selective shunting may be safely performed in carotid surgery.     

Lung findings on thoracic high-resolution computed tomography in patients with ankylosing spondylitis. Correlations with disease duration,clinical findings and pulmonary function testing

The aim of this study was to identify the spectrum of abnormalities revealed on high-resolution computerized tomography (HRCT) in patients with ankylosing spondylitis (AS), to compare findings with those of plain radiography and pulmonary function testing (PFT), and to look for correlations between lung involvement and AS severity. We prospectively studied 55 consecutive patients with a diagnosis of AS according to the modified New York criteria who attended our department over a period of 2 years. All patients had a detailed rheumatological examination and underwent plain chest radiography, chest HRCT and PFT. HRCT revealed abnormalities in 29 patients (52.7%), whereas plain chest radiography was abnormal in only 2. Abnormalities consisted of interstitial lung disease (ILD) (n=4), apical fibrosis (n=5), emphysema (n=5), bronchiectasis (n=4), ground glass attenuation (n=2), and non-specific interstitial abnormalities (n=26). Only apical fibrosis and bronchiectasis were statistically more frequent with increasing disease duration (significant trend ²test, p=0.0029 and 0.028, respectively). PFT showed a restrictive process in 19 patients (34.5%). No correlation was noted between HRCT and PFT, nor with AS symptomatic and structural severity parameters. However, there was a statistically significant correlation between PFT and AS symptomatic and structural severity parameters. In conclusion,: this study confirms that the chest HRCT of patients with AS showed a great number of abnormalities undetectable by standard X-rays. The high incidence of lung abnormalities emphasizes the importance of excluding such a diagnosis in patients with AS even without respiratory symptoms.Abbreviations AF Apical fibrosis - AS Ankylosing spondylitis - FVC Forced vital capacity - FEV₁ Forced expiratory volume in 1 s - HRCT High-resolution computerized tomography - ILD Interstitial lung disease - PFT Pulmonary function tests - VC Vital capacity     

Small airways diseases: detection and insights with computed tomography.

Diseases affecting the small airways are difficult to detect by traditional diagnostic tests. Widespread involvement is needed before symptoms and abnormalities on pulmonary function testing or chest radiography become apparent. Obstruction of the bronchioles may be detected indirectly by computed tomography (CT) because regional under-ventilation results in reduced perfusion which in turn is shown as a mosaic attenuation pattern of the lung parenchyma. When there is inflammation of the bronchioles with accompanying exudate, the airways may become directly visible on CT, for example in cases of diffuse panbronchiolitis. Quantification of the various morphological features of small airways disease is possible from CT images and this increased precision has aided investigations of structure/function relationships. An understanding of the pathology and microscopic distribution of disease in relation to the airways allows some prediction of the likely computed tomography appearances in this wide spectrum of conditions, and thus helps to refine the differential diagnosis.     

Correlations of single photon emission computed tomography joints scan and bone metabolic markers in active rheumatoid arthritis

正Objective To explore the correlation between quantitative value of joint bone scan by single photon emission computed tomography(SPECT)and serum bone metabolic markers in patients with active rheumatoid arthritis(RA).Methods Clinical data of 60 newly diagnosed RA patients were retrospectively collected in Department of