K.H. Chan

Postictal psychosis related regional cerebral hyperperfusion

Postictal psychosis is a known complication of complex partial seizure in particular temporal lobe epilepsy. It usually runs a benign and self limiting course. A postictal phenomenon with focal cerebral hypofunction (similar to Todds palsy), rather than ongoing seizure activity, has been postulated.1 2 Surface EEG is either normal or showing non-specific slow waves.3 Hence, antipsychotic medications are prescribed instead of antiepileptic drugs. Until recently, the pathogenic mechanisms have remained unknown. In this communication, we report on two patients with postictal psychosis, during which a cerebral SPECT study showed a hyperperfusion signal over the right temporal lobe and contralateral basal ganglion. As hyperperfusion in ictal cerebral SPECT is closely linked to epileptic activities,4 our findings support a contrary explanation for postictal psychosis. nnnnInterictal SPECT and SPECT performed during postictal psychosis. (Top) A SPECT study of patient 1 showing areas of relative hyperperfusion over the right temporal neocortex (red arrows) and the left basal ganglia (blue and yellow arrows) during postictal psychosis. (Bottom) SPECT study of patient 2 showing areas of hyperperfusion over the right temporal neocortex and the left basal ganglia. Arrows indicate areas of hyperperfusion.nnnnProlonged video-EEG telemetry study was performed in patients who underwent presurgical evaluation for epilepsy surgery. Antiepileptic drugs were withdrawn …

Knowledge of Stroke in Hong Kong Chinese

A random telephone survey on knowledge of stroke was conducted in 1,238 Hong Kong Chinese. Most respondents realized that effective treatment was available, that stroke was preventable and that it could be fatal or disabling. Sudden unilateral limb weakness, sudden speech and language disturbances, and sudden vertigo and clumsiness were better recognized than other warning symptoms of stroke. A slightly better recognition of symptoms of stroke was seen in those with a belief of knowing about stroke, providing a correct description of stroke, those with a positive household history of stroke and those with a better knowledge of potential risk factors. Most respondents would choose desirable actions if stroke was suspected in their family members or themselves. Friends and relatives, newspapers and magazines, and mass media provided the major sources of their knowledge.

Neuromyelitis optica-IgG in idiopathic inflammatory demyelinating disorders amongst Hong Kong Chinese

Background:u2002 Idiopathic inflammatory demyelinating disorders (IIDD) affect the central nervous system. In classical multiple sclerosis (CMS), brain, optic nerves [optic neuritis (ON)] and spinal cord [acute transverse myelitis (ATM)] are affected. In neuromyelitis optica (NMO), optic nerves and spinal cord are predominantly affected. NMO‐IgG, an autoantibody targeting aquaporin‐4, is a marker for NMO. We studied the frequency and clinical relevance of NMO‐IgG seropositivity in IIDD patients.

Circadian Variation of Stroke Onset in Hong Kong Chinese: A Hospital-Based Study

Circadian variation of onset of transient ischaemic attack (TIA) or stroke during four 6-hourly periods starting from midnight was studied in Hong Kong Chinese patients admitted to a regional hospital between October 1996 and July 1999. The onset was classifiable into one of the 6-hourly periods in 832 of 905 patients; patients with unclassifiable onset were more likely to have lacunar infarct and less likely to have intracerebral haemorrhage (ICH). There was a significant circadian variation of onset in all strokes and TIA, TIA alone, ischaemic stroke (IS), ICH and different IS subtypes. The risk of onset was greatest between 6 a.m. and noon for IS or TIA, but between noon and 6 p.m. for ICH. There was no difference in the circadian variation between patients with and without prior TIA or stroke. This hospital-based study revealed a significant circadian variation of onset in different types and subtypes of stroke.

Wilson’s disease with depression and parkinsonism

Wilsons disease (WD) is an autosomal recessive disorder with reduced biliary excretion of copper plus impaired formation of ceruloplasmin, leading to copper accumulation in the liver, brain, kidney, and cornea. Clinical manifestations include liver damage, psychiatric symptoms, and neurological features. We report a 35-year-old woman with a history of deranged liver functions who had severe depression several years later and eventually presented with parkinsonian features. The underlying diagnosis is WD and family screening revealed WD in 2 other siblings. She could not tolerate penicillamine because of fever and leucopenia. While taking trientine hydrochloride and zinc sulphate, her parkinsonism improved and her depression remained in remission. WD should be considered in patients with unexplained liver function derangement or psychiatric symptoms. Early diagnosis and initiation of specific treatment are crucial in minimising any further cerebral and hepatic damage as well as securing possible improvement in organ functions.

Warfarin associated intracerebral hemorrhage in Hong Kong Chinese

Abstract Objectives: Warfarin-associated intracerebral hemorrhage (WICH) is a serious neurological condition associated with significant mortality and morbidity. We aimed to study the clinical features and factors that predict clinical outcome of Chinese patients with WICH. Methods: Medical records of patients with spontaneous intracerebral hemorrhage (ICH) admitted to our hospital between July 2001 and June 2010 were reviewed and those with WICH were studied in detail retrospectively. Results: Fifty-one patients with WICH were studied. The mean age was 74·3 ± 10·5 years and 52·9% of the patients were female. The mean international normalized ratio (INR) on presentation was 2·9 ± 1·0. The median ICH volume was 23·3 (10·4–59·3) ml. The mortality rate at 3–6 months for WICH was 62·0%. Multivariate logistic analysis revealed that an initial ICH volume of > 20 ml (OR 34·4, P u200a=u200a 0·037) and presence of intraventricular hemorrhage (OR 22·9, P u200a=u200a 0·046) were independently associated with poor outcome. Supratherapeutic INR (INR > 3·0) on admission (P u200a=u200a 0·724) and complete correction of INR within 24 hours after admission (P u200a=u200a 0·486) were not independent predictors of poor outcome. The median ICH volumes did not differ between INR groups (18·2 (9·4–61·1) ml for INR ≤ 3 vs 27·3 (13·7–58·5) ml for INR > 3, P u200a=u200a 0·718). Neurological deterioration (ND) was documented in 19 (63·3%) of the 30 patients included in a smaller sub-cohort, and was associated with poor neurological outcome (OR 20·7, P u200a=u200a 0·027). Warfarin was resumed in 7 of the 20 survivors. There were two episodes of recurrent WICH and one episode of ischemic stroke during a mean follow-up duration of 5·4 years. In survivors who were not resumed on warfarin, there were two episodes of recurrent ICH and 12 episodes of ischemic vascular events (nine ischemic strokes) during a mean follow-up duration of 2·6 years. Conclusion: Warfarin-associated intracerebral hemorrhage is a very serious complication of warfarin therapy with high mortality and morbidity. Initial ICH volume, presence of intraventricular hemorrhage, and ND are independent predictors of clinical outcome.

Clinical outcome of relapsing remitting multiple sclerosis among Hong Kong Chinese.

BACKGROUNDnClinical outcome of Chinese relapsing remitting multiple sclerosis (RRMS) patients is uncertain.nnnAIMnTo study the long-term clinical outcome of Chinese RRMS patients.nnnMETHODnRRMS patients with duration of 10 years or longer followed up in our hospital is retrospectively studied.nnnRESULTSn61 RRMS patients (75% female) were studied. Their mean symptom onset age was 25.9 years and mean duration was 20.6 years (range 10-33); 36% patients had received β-interferon and 30% azathioprine. Their mean EDSS scores were 3.3 (range 1-7) and 4.7 (range 1-8) at 10 years and latest follow-up (mean duration 20.6 years) respectively. At 10 years, 30% patients had EDSS score ≤2, 34% EDSS 2.5-3.5, 20% EDSS 4.0-5.5 and 16% ≥6; 18% developed SPMS. At latest follow-up, 15% patients had EDSS ≤2, 20% EDSS 2.5-3.5, 19% EDSS 4.0-5.5 and 46% ≥6.0; 53% developed SPMS. The median time from symptom onset to EDSS 6 was 22 years. No differences were detected in demographic characteristics, presenting neurological features, number of attacks in first 2 years, neuroradiological findings and disease modifying therapies between patients with EDSS <6 and ≥6 at ten years. EDSS scores at 10 years and latest follow-up were similar for patients who had received β-interferon and those who had not.nnnCONCLUSIONnHong Kong Chinese RRMS patients may have worse long-term clinical outcome than Caucasian patients.

Nonthymoma early-onset- and late-onset-generalized myasthenia gravis--a retrospective hospital-based study.

OBJECTIVEnAcquired myasthenia gravis (MG) is predominantly due to nicotinic acetylcholine receptor (AChR) autoantibodies (Ab). Differences between nonthymoma early-onset and late-onset MG were reported. We studied the clinical and serological characteristics of nonthymoma AChR Ab-positive-generalized MG patients.nnnPATIENTS AND METHODSnChinese AChR Ab-positive-generalized MG patients who had generalized disease for 3 years or longer were studied.nnnRESULTSnAmong 41 such patients, 25 (61%) were female. The mean onset age was 43.5 years (range 9-78 years) and the mean follow-up duration was 7.8 years (range 3-20 years). Sixteen (39%) patients had late-onset disease (onset age >or=50 years). Compared to early-onset patients (onset age <50 years), late-onset patients were characterized by male predominance (p=0.002), absence of thymic lymphofollicular hyperplasia (p=0.036), and a higher striated muscle Ab seropositivity rate (94% versus 4%, p<0.001). Although there was no statistically significant difference in clinical severity and outcome or response to treatment between late-onset and early-onset patients, 50% and 75% of late-onset patients had moderate or severe disease at onset and worst status, respectively, compared to 28% and 52% for early-onset patients at onset and worst status, respectively. Also 63% of late-onset patients had disease progressed within first 3 years compared to only 40% of early-onset patients did.nnnCONCLUSIONnNonthymoma late-onset-generalized MG patients were common among Hong Kong Chinese, with a statistically non-significant trend that it was clinically more severe than early-onset MG but with similar clinical outcome or response to treatment; >90% of these patients were seropositive for striated muscle Ab.

Hypertensive encephalopathy: BP lowering complicated by posterior circulation ischemic stroke

In hypertensive encephalopathy (HTE), prompt reduction of blood pressure (BP) is essential to prevent permanent neurologic and other damages. Radiologically, HTE is characterized by white-matter edema affecting preferentially the occipital lobes and other posterior structures.1 The clinical and radiologic manifestations of HTE usually resolve completely after correction of hypertension.1,2⇓ We report two patients in whom neurologic deterioration occurred paradoxically with treatment of HTE.nn### Patient 1.nnA previously healthy 36-year-old Filipino man presented with acute headache, confusion, bilateral visual loss, and BP of 260/130. There was no other focal neurologic deficit on admission. Retinal examination was unremarkable. Brain CT revealed white-matter edema at the occipital lobes. After 50 mg bolus of IV labetalol, BP was reduced with the lowest reading at 140/110. Two hours later, he developed acute pulmonary edema and generalized seizures. He was transferred to the Intensive Care Unit (ICU) and was ventilated under sedation. EKG showed no evidence of myocardial ischemia. His condition was stabilized, and he was extubated 40 hours later. Physical …

Paraneoplastic motor neuropathy and inflammatory myopathy associated with nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is common in Southern Chinese and relatively young patients are affected [1]. Despite being potentially treatable by irradiation, local recurrence and metastases are lifethreatening. Dermatomyositis (DM), urticarial vasculitis, pulmonary osteoarthropathy, clubbing of fingers and myelemia are known paraneoplastic conditions associated with NPC [1]. Paraneoplastic DM occur before, simultaneously or follow the diagnosis of NPC in 0.9–3.9% patients. Up to 25% of malignancy detected in paraneoplastic DM was NPC. Diagnosis of DM trigger aggressive search for underlying malignancy including NPC. We reported a patient who developed paraneoplastic subacute predominantly motor polyneuropathy/polyradiculoneuropathy and inflammatory myopathy without skin rash simultaneously upon recurrence of NPC. Case report