Biomedical subjects

K K Tang

Publications and source records attributed to K K Tang.

6 recordsLinked to original sources

PubMed2004

Monophasic, solitary tumefactive demyelinating lesion: neuroimaging features and neuropathological diagnosis.

The characteristic clinicoradiological findings of multiple sclerosis and acute disseminated encephalomyelitis (ADEM), demonstrating a recurrent progressive course in the former and monophasicity in the latter associated with multiple discrete white matter lesions with variable enhancement on MRI, are not a diagnostic challenge. On the other hand, the less typical radiological presentation of a solitary tumefactive demyelinating lesion mimics a neoplasm, and often necessitates a biopsy. Nonetheless, histopathological examination is an imperfect gold standard and the recognition of certain imaging features may facilitate the correct diagnosis.

Adult↗

PubMed2002

Is postoperative deep vein thrombosis a problem in neurosurgical patients with brain tumours in Singapore?

AIM: To prospectively establish the incidence of deep vein thrombosis (DVT) after cranial procedures in patients with brain tumour in Singapore. METHODOLOGY: Over a period of one year from June 1995 to May 1996, 106 consecutive patients were recruited into the study. All patients undergoing surgery within the period of study were included. Each patient underwent a preoperative and postoperative (on postoperative Day 5 to Day 7) ultrasound examination of the lower limbs to establish the presence of DVT. Prophylaxis was limited to the peri-operative use of elastic stockings on hemiparetic limbs. There were 56 males and 50 females aged between 22 to 86 years (median 45 years). Ethnicity was Chinese, 92% Indian, 6% and other 2%. Ninety percent of the patients were ambulant pre- and post-operatively. No patient had a prior history of DVT. The distribution by pathologic diagnosis was brain metastases, 26% meningioma, 26% glioma, 19% pituitary adenoma, 14% acoustic neuroma, 6% and 9% miscellaneous tumours. RESULTS: DVT was identified in 5/106 patients (4.7%), all of whom had either meningioma or glioma. All five cases occurred in supratentorial tumours. The tumour specific incidence was 7.1% for meningioma and 15% for glioma. 4/5 patients (80%) had pre-existing hemiparesis of the affected limb. No patient developed clinical pulmonary embolism. CONCLUSION: The overall incidence of postoperative DVT in our population, using minimal prophylaxis, was not significantly different from the best results of prospective studies on North American or European patients employing a full regime of prophylaxis. The high-risk groups were similar. Prophylaxis using subcutaneous heparin should be used cautiously in high-risk patients.

Adult↗

PubMed2002

Review of carotid endarterectomy at Singapore General Hospital.

AIM: To review the outcome of a consecutive series of patients undergoing carotid endarterectomy in a low volume setting. DESIGN: Retrospective case review. PATIENTS: During an 11-year period we performed 50 elective carotid endarterectomies on patients with symptomatic severe carotid stenosis: Ages of patients raised from 40 to 87 years (mean 68 years), 88% were Chinese, 6% Malay and 4% Indian. Twenty-eight percent had coronary artery disease, 64% hypertension, 27% diabetes mellitus, 50% hyperlipidaemia, and 52% were smokers. None of the patients had prior neck surgery or radiotherapy. RESULTS: There were no deaths in this series of 50 cases. Ninety-eight percent of our patients came through surgery without major neurologic deficit. One patient (2%) suffered a major perioperative stroke. Minor neurologic sequelae included one patient (2%) with a mild non-disabling stroke, two patients (4%) with peri-operative TIA without significant sequelae; two patients (4%) with transient cranial nerve weakness (one vagus, one facial nerve). CONCLUSION: The surgical outcomes in this series are comparable to that from larger series. Carotid endarterectomy can be safely done in a low volume setting.

Adult↗

PubMed1998

Radon properties in offices.

The radon concentration (RC), total potential alpha energy concentration of radon decay products (PAEC), equilibrium factor (F), and the fraction of unattached radon decay products (fp) were measured for 94 offices in Hong Kong. The mean values for RC, PAEC, F, and fp were 51 Bq m(-3), 1.19x10(-7) J m(-3) (5.7 mWL), 0.43, and 0.13, respectively. The first three are much higher than the corresponding values for dwellings. The radon properties vary significantly for different sites. The time for measurements, cumulative time since the air conditioning system was turned on, and whether smoking is allowed in the office have been identified from the available data as possible factors affecting the radon characteristics in offices. The mean contribution of the lung exposure to the annual effective dose equivalent due to radon in offices has been calculated to be 0.35 mSv y(-1). Considering other sources of natural radiation, a rough estimate of the total annual equivalent dose of about 2.7 mSv for a person living in Hong Kong is obtained. Two simple methods are proposed to mitigate the radon hazard in offices: (1) the provision of smoke-free environments and (2) switching on the air conditioners earlier. The first method reduces the equivalent dose by about 0.13 mSv y(-1) while the second reduces by about 0.1 mSv y(-1), which can be regarded as significant.

Air Conditioning↗

PubMed1997

Video-endoscopic and mini-endoscopic sympathectomy for hyperhidrosis.

Video-endoscopic sympathectomy (VES) is currently the method of choice for the minimally invasive treatment of hyperhidrosis involving the palms, armpit and facial areas. Over a 7-year period from 1991 to 1997 our technique of performing VES has evolved during the performance of 800 endoscopic sympathectomies from the use of 3 ports to a single 10-mm port to finally a 3-mm port using a mini-endoscope. In comparison to standard VES, mini-endoscopic sympathectomy is simpler, less invasive, causes less postoperative discomfort and consistently allows patients to return home the same day.

Adult↗

PubMed1991

Cognitive-behavioural group therapy for Hong Kong Chinese adults with mental health problems.

Ninety-one Chinese in the community, aged between 18 and 45, with mental health problems ranging from mild to moderate degree, were treated by cognitive behavioural group therapy (CBGT) for a period of 3 months. All subjects were assessed on multiple measures at 4 time points: screening, pre-treatment (after 3 months), post-treatment and at 3-month follow-up. Attendance was good. A standard practice manual was developed to ensure consistent treatment by 2 group workers. After controlling for the placebo effect in the waiting period, treatment effect was demonstrated which was sustained after a three month period. The all-round improvement included a decrease in psychiatric symptoms, improvement in self-assessment, better and more social activities and being more able to cope with problems. In terms of psychiatric diagnosis, depressed subjects gained the most benefit and personality disorder subjects the least. Parents seemed to benefit more than non-parents.

Adaptation, Psychological↗