Usefulness of ocular compression during electroencephalography in distinguishing breath-holding spells and syncope from epileptic seizures

Episodes of syncope or breath-holding spells are often misdiagnosed as epileptic events. The purpose of this study was to assess the usefulness of an electroencephalogram (EEG) with ocular compression to distinguish breath-holding spells and syncope from epileptic seizures. A retrospective analysis was performed on the EEG records of all children on whom ocular compression was performed from 2000 to 2003. Data from 116 patients with a clinical diagnosis consistent with either syncope or breath-holding spells were compared with a group of 46 patients with epilepsy. The RR interval during ocular compression was significantly higher in syncope patients compared with patients with epilepsy (P < .005). Using 2 seconds of asystole as the cutoff, the sensitivity of ocular compression was 26%, with 100% specificity. The change in RR interval from baseline to ocular compression also distinguished patients with breath-holding spells and syncope from patients with epilepsy. Even a small increase of 0.5 seconds in the RR interval demonstrated a sensitivity of 46%, with a specificity of 98%. Ocular compression performed during an EEG is useful in distinguishing patients with breath-holding spells and syncope from those with epileptic seizures. A requirement of a 2-second period of asystole with ocular compression excludes many patients. Our data indicate that an RR interval increase of 0.5 seconds over baseline identifies additional patients with increased vagal tone. Prompt and accurate diagnosis of the etiology of loss of consciousness might preclude the need for further extensive and expensive evaluation and reduce patient and parental distress.     

Exaggerated Valsalva maneuver may explain stretch syncope in an adolescent

We describe cardiovascular responses during the Valsalva maneuver and syncope in the youngest reported patient with stretch syncope, which was induced by neck stretching and back hyperextension. The pattern of cardiovascular responses during stretch syncope was similar to that during a pathologic Valsalva maneuver, indicating adrenergic dysfunction in this patient. These findings indicate that the underlying mechanisms of these two processes are not fundamentally different, and that adrenergic dysfunction observed during the Valsalva maneuver may have resulted in stretch syncope in this patient. However, a simple Valsalva maneuver should not have sufficed to precipitate these episodes, because no syncope or significant hypotension occurred during the Valsalva maneuver. Thus, we suggest that additional factors, such as mechanical compression of vessels or physiologic responses to orthostasis, were aggravated during pathologic Valsalva maneuver responses, which were responsible for the stretch syncope observed.     

倾斜试验三步法诊断血管迷走性晕厥

目的探讨三步法倾斜试验在诊断血管迷走性晕厥中的作用。方法根据药物诱发血管迷走性晕厥的机制不同,采用倾斜试验三步法即依次为基础倾斜试验、合化硝酸甘油倾斜试验、异丙基肾上腺素倾斜试验对600例不明原因晕厥患者进行检查和观察。结果参检人数的82％在本试验中先后出现阳性,比单种药物激发试验的阳性率至少提高12％。结论倾斜试验三步法应用于临床诊断血管迷走性晕厥,安全、敏感性高,值得推广。     

Clinical diagnosis of syncopes (including so-called breath-holding spells) without electroencephalography or ocular compression

A recent article in this journal suggested that ocular compression during electroencephalography was useful in distinguishing "breath-holding spells and syncope" from epileptic seizures. The method proposed involved measurement of the RR interval on the simultaneously recorded electrocardiographic trace and determining both the absolute RR lengthening and the change in RR interval as compared with the baseline value. It is argued by the present author that this is not an appropriate way to come to a diagnosis in episodic loss of consciousness in children. It is pointed out that so-called "breath-holding spells" are reflex syncopes and that the diagnosis of reflex syncopes should be by clinical history, even if this means delaying the diagnosis until a future consultation. Published evidence on the nature and clinical diagnosis of reflex syncopes in infants and children is reviewed in depth. It is concluded that routine electroencephalography is not an appropriate investigation when the diagnosis of episodic loss of consciousness is in doubt and has the implicit danger of false positive "abnormality". Aside from scientific exploration of the developing autonomic nervous system, the only current indication for diagnostic ocular compression is to induce a syncope so that its nature may be better understood. Such a circumstance might be a history of an apparent reflex syncope but with atypical features, including prolonged post-syncopal unconsciousness such as might indicate epileptic absence status. Several additional investigations of a primarily cardiological nature may be indicated in some cases, but a wait-and-see policy is usually to be preferred.     

Cardiogenic syncope. Seizure versus syncope

Our recommendations for the evaluation of the patient with suspected cardiogenic syncope are as follows: An initial thorough history and physical examination of the patient will suggest the diagnosis of cardiogenic syncope in at least 50 per cent of patients. A sudden occurrence of syncope, or "drop attack", is most suggestive of an arrhythmic cause for syncope. If there is no evidence of neurologic, metabolic, or obvious cardiac (for example, aortic stenosis) cause for syncope, a 24-hour ambulatory ECG should be performed. If the patient has had repeated syncopal episodes or if the patient has had seizures that are difficult to control with anticonvulsant therapy, ambulatory ECG monitoring may reveal an arrhythmia in these preselected patients. If the initial 24-hour ambulatory ECG is negative and if the patient has had multiple episodes of syncope, multiple days of recording will be necessary before typical symptoms occur that correlate with arrhythmias. Seventy-two hours of ambulatory ECG monitoring should be sufficient in most instances to establish an arrhythmic cause for syncope. Echocardiography and exercise stress testing are not routinely indicated in the evaluation of syncope unless the clinical history and examination suggest valvular or coronary disease. Rarely, an atrial myxoma will be visualized by echocardiography that is not apparent clinically. Those patients who still have unexplained recurrent syncopal episodes, despite all noninvasive studies, can benefit from invasive electrophysiologic studies, although the expected yield from electrophysiologic testing is low.     

123I-metaiodobenzylguanidine myocardial scintigraphy in the differential diagnosis of patients with parkinsonian syndromes -- case reports

The aim of this study is to present a clinical role for 123I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy in the differential diagnosis in patients with parkinsonian syndromes. We present a 51-year-old woman with parkinsonian syndrome and syncope occurrence. She reproduced spontaneous syncope in the tilt test. We present also a 60-year-old man with parkinsonian syndrome and syncope and presyncope occurrence. He also reproduced spontaneous syncope in the tilt test. Cardiac 123I-MIBG scintigraphy was performed in both patients. In the former patient, the H/M ratio of MIBG uptake was within normal ranges, in the latter, it was abnormally impaired. The results of the 123I-MIBG cardiac scintigraphy confirm results of the other studies. In the patient with Parkinson's disease the H/M ratio of MIBG uptake was abnormally impaired. The patient with the multiple system atrophy was within normal ranges.     

NATURAL HISTORY OF MICTURITION SYNCOPE

A follow-up study was performed on 10 patients with micturition syncope 5–15 years after their initial attack. Three patients had died of cardiac or pulmonary diseases (at age 61, 69 and 82 years). One had developed focal motor epilepsy which was considered to be unrelated to his previous attack of micturition syncope. Only (age 60) developed a hemianopsia in connection with his micturition syncope. Only one patient had had a new attack of micturition syncope which had occurred during a febrile illness. Two often sit down prophylactically during micturition. It is concluded that micturition syncope most often is a benign phenomenon which should be distinguished from epilepsy. The patient may be advised to sit down during micturition, especially at night, but treatment is otherwise not necessary.     

Kearns-Sayre综合征一例临床病理分析

目的探讨Kearns-Sayre综合征(KSS)的临床与病理形态学表现,旨在提高对该病的认识。方法对1例KSS患者的临床和病理特点进行分析。结果该患者表现为视物不清、双上睑下垂、慢性进行性眼外肌瘫痪、视网膜色素变性,眼底色素改变呈"椒盐状"、晕厥发作、心脏传导阻滞、小脑性共济失调、不育、脑脊液蛋白升高、脑脊液叶酸/血清叶酸比值降低。肌肉活检MGT染色发现有不整红边纤维(RRF),出现比例为11.6%。电镜观察表现为线粒体数目增多,形态异常,嵴排列紊乱等,可见线粒体内类结晶状包涵体。结论本例提示尽管KSS的临床表现多样,但对不明原因的单侧或双侧上睑下垂、眼球运动障碍伴视网膜色素变性和晕厥等症状的患者,应想到KSS的诊断,进行肌肉活检、遗传咨询和采取必要的措施,防止威胁生命的事件发生。     

Transcranial Doppler and angiographic findings in adolescent stretch syncope.

The clinical, angiographic, and Doppler findings are reported for two young patients with recurrent syncope induced by neck hyperextension during stretching. Transcranial Doppler monitoring of both posterior cerebral arteries was performed during head manoeuvres. There were reproducible rapid decreases in blood flow velocities in both patients to an average of 28% and 41% of baseline values when they performed neck hyperextension. These decreases were regularly associated with the patients' symptoms and were not found during rotation or flexion. On return to a neutral head position there was a transient increase of the blood flow velocities to an average of 131% and 136% of baseline values (reactive hyperaemia). Routine four vessel angiography was normal except for the demonstration of very small posterior communicating arteries in one patient. Dynamic angiography showed evidence of extracranial compression of the craniocervical arteries in both patients. It is concluded that decreased blood flow to the posterior circulation is an important factor in the pathogenesis of adolescent stretch syncope.     

Differenzialdiagnose paroxysmaler Bewusstseinsstörungen

Paroxysmal cardiac arrhythmias are an important differential diagnosis of epileptic seizures. Their clinical diagnosis is of particular importance as cardiac syncope is associated with a higher mortality. Therefore an actual surface ECG should be carefully examined and further cardiological diagnostics should be considered.We report on a patient with torsade de pointes tachycardia due to a long QT syndrome. Representative episodes were recorded during video EEG monitoring, as a diagnosis of epilepsy was assumed.     

Spinal meningioma becoming symptomatic in the third trimester of pregnancy

We report a rare case of a spinal meningioma leading to symptoms of spinal cord compression starting in the third trimester of gestation in a 32-year-old woman. Neurological symptoms, which continued to progress after the patient had given birth, were assumed to be sequelae of pregnancy and delivery, leading to a 6 month delay in diagnosis and treatment. Fortunately a gross total resection was achieved at surgery and the patient recovered fully, without permanent consequences. Associated symptoms of spinal cord compression may be falsely attributed to pregnancy, both by the pregnant women and her treating physician. A high index of suspicion and thorough history and physical examination to identify red flags should be performed in patients with neurological symptoms.     

Hereditary long Q-T syndrome presenting as epilepsy: electroencephalography laboratory diagnosis

Patients with hereditary Q-T interval prolongation can present with seizures, syncope, and sudden death. In 2 siblings with autosomal dominant familial long Q-T syndrome, electroencephalographic examinations performed 6 and 2 years before diagnosis included electrocardiographic tracings documenting the cardiac abnormality. A timely diagnosis of this condition may have prevented the death of 1 of these patients. Measurement of the corrected Q-T interval on electrocardiographic tracings obtained in the electroencephalography laboratory should be considered in selected patients.     

Diagnosing epilepsy in neurology clinics: A prospective study

The certainty of the initial diagnosis of epilepsy was assessed prospectively by one neurologist in outpatients. One hundred and fifty-eight consecutive referrals with loss of consciousness or possible epilepsy were seen. The relative contributions to the initial diagnosis from the referral letter, history taking in clinic, physical examination, and investigation were compared. There was a referring diagnosis in 28.5%. The neurologist reached a diagnosis in 87% of the 158 cases: in 43% epilepsy, 25% syncope, 12% non-epileptic seizures and in 7% other diagnoses. There was a low correlation between referral and specialist diagnosis. Physical examination did not change the diagnosis in any patient. Investigations changed the diagnosis in one patient. Neuro-imaging revealed a relevant abnormality in 12/43 (27.9%) scanned. The yield from EEG was 7/25 (28%), but the EEG changed the diagnosis in only one case. Cardiac testing confirmed the type of syncope in 2/47 (4.3%) of patients. Blood tests did not contribute to the diagnosis in any patient. The neurology consultation significantly increased diagnostic certainty. The diagnosis of epilepsy remains largely clinical. It is important that patients are aware of this prior to investigation.     

Current approaches to the clinical assessment of syncope in pediatric population

Introduction

Syncope is one of the most common clinical problem in children. This disorder is characterized by transient, spontaneously self-terminating loss of consciousness with brief duration and complete recovery. This situation is usually alarming for the families of patients. The mechanism of syncope is transient global brain hypoperfusion to levels below those tolerated by cerebrovascular autoregulation. Syncope can occur with many different etiologies in the pediatric population.

Classification

Syncopes are divided into three major categories as neurally mediated syncope, cardiovascular-mediated syncope, and non-cardiovascular syncope.

Clinical features

The major challenge in the assessment of children with syncope is that most children are asymptomatic at the time of their presentation, therefore making a careful and detailed history and a comprehensive physical examination essential in all patients. A trigger stimulus is detected in some cases, and this is an important clinical clue for the diagnosis. Cardiac causes of syncope in children are rare but can be life threatening and have the highest risk of morbidity and mortality. Misdiagnosis of epilepsy is common in patients presenting with syncope; therefore, the differential diagnosis between epileptic seizures and syncope is very important. It should be remembered that the evaluation of syncope in children is costly and diagnostic workup has a limited diagnostic yield.

Conclusion

The aim of this article is to present different types of syncope and to provide new practical clinical approaches to the diagnosis, investigation, and management in the pediatric population.

     

中枢神经系统血管内淋巴瘤病一例报告

目的通过对１例中枢神经系统血管内淋巴瘤病患者的临床、影像学和脑组织病理检查,探讨此病的诊断规律。方法对患者的临床症状及影像学改变进行系统观察,对脑手术标本进行组织学和免疫组织化学染色。结果患者,５０岁,男性。表现为亚急性脑病,病情迅速恶化,于病后４６天死亡。辅助检查发现血沉加快,脑脊液仅出现蛋白轻度升高。影像学检查显示大脑白质多灶性损害,随病程的延长,病灶迅速增大、增多。脑病理特点为广泛的血管内恶性Ｂ淋巴瘤细胞增殖,导致血管堵塞,白质内出现多发性陈旧及新鲜的缺血病灶。结论此病的诊断只能依靠脑病理学检查。临床鉴别诊断包括恶性胶质瘤、进行性多灶性白质脑病、多发性硬化和颅内血管炎。     

Cough syncope with hypertension—caused by brainstem compression?

The commonly accepted pathophysiological changes in cough syncope include a fall in systemic blood pressure, raised intracranial pressure and cerebral ischemia. However, cases of cough syncope without hypotension have been reported in patients with the Arnold–Chiari malformation. We describe a 48-year old man with cough syncopes. Constant blood pressure monitoring revealed hypertension instead of the expected hypotension during the episodes. Attacks of loss of consciousness were associated with motor phenomena, i.e. tonic posturing and tonic spasm. Magnetic resonance imaging revealed compression and displacement of the medulla oblongata by an ectatic and elongated vertebral artery. The commonly accepted mechanism of cough syncope cannot explain the symptoms in our patient because a fall of blood pressure was lacking. Instead, a cough-induced compression of the displaced brainstem may have caused a transient dysfunction of the reticular formation.     

Syncope in childhood: a case control clinical study of the familial tendency to faint

We investigated the possibility of an inherited tendency to faint by studying 30 consecutively referred well children with vasodepressor or vasovagal syncope. The family history of each patient was reviewed for syncope and for 24 cases was compared with the family history of the child's best friend. None of the best friends had syncope. 27/30 cases and 8/24 best friends had at least one first degree relative with syncope (p less than 0.01). Of the 8 best friend controls with a parent or sibling with syncope, the mother was affected in 7; 4/7 of these mothers had first degree relative(s) with syncope. In 11/30 patients both a sibling and parent had syncope compared with 1/24 of control families (p less than .01). We conclude that there is an inherited tendency to faint since most children who faint have a first degree relative who faints, a useful fact in differential diagnosis. This inherited tendency may be multifactorial but requires an environmental stimulus for expression.     

Eye examination-induced syncope

The role of trigeminal afferents in a patient with eye examination – induced syncope was investigated. A head-up tilt test precipitated presyncope with a reduced blood pressure. On a separate day, the application of Schirmer's lacrimation test strips in each conjunctival sac caused vasodepression and cardioinhibition. Topical administration of 0.5 % proparacaine hydrochloride produced ocular anesthesia and loss of corneal reflexes. Schirmer's test following anesthesia again caused presyncope with reductions in blood pressure and heart rate. The supramaximal stimulus to a supraorbital nerve before and after topical anesthesia did not affect blood pressure or heart rate. It is concluded that trigeminal afferents did not induce vasodepressive syncope in this patient. Instead, corticohypothalamic centers may have played an important role. Received: 9 January 2002, Accepted: 6 March 2002     

Gestural automatisms during syncope related to cervical malignancy

Cervical malignancies are a rare but well-known cause of syncope. Gestural automatisms during syncope have only rarely been reported. We describe a patient presenting with bimanual automatisms during syncopal episodes caused by parapharyngeal carcinoma involving the right laterocervical region. Ictal phenomenology was strongly suggestive of focal seizures and only video-polygraphic recording including EEG and ECG allowed the correct diagnosis to be established. Syncopal episodes ceased after partial removal of the mass. Although gestural automatisms in the context of a sudden spell with loss of consciousness are strongly suggestive of focal (mainly frontal or temporal) seizures, the diagnosis of syncope must be taken in account and confirmed or excluded by appropriate neurophysiological investigations.     

Seizures and syncope:

Abstract Although pathophysiologically distinct, syncope and seizures share clinical characteristics which may make diagnosis difficult. Adding to diagnostic complexity are the facts that seizures and syncope may coexist in the same patient, syncope may be associated with seizure-like motor manifestations, and seizures may be complicated by cardiac arrhythmia and syncope. Combined EEG/ECG telemetry is sometimes necessary to establish the correct diagnosis. These techniques also provide an opportunity to study the role of certain cortical regions in the modulation of cardiac function. There is an increasing understanding of the central autonomic pathways involved in the genesis of the cardiovascular changes that occur during epileptic seizures. This article reviews the use of EEG/ECG telemetry in the evaluation of syncope and seizures, and the neuroanatomic circuitry involved in the production of the cardiovascular manifestations of seizures.