Multiple matching scheme for broadband 0.72Pb(Mg(13)Nb(23))O(3)-0.28PbTiO(3) single crystal phased-array transducer

Lead magnesium niobate-lead titanate single crystal 0.72Pb(Mg(13)Nb(23))O(3)-0.28PbTiO(3) (abbreviated as PMN-PT) was used to fabricate high performance ultrasonic phased-array transducer as it exhibited excellent piezoelectric properties. In this paper, we focus on the design and fabrication of a low-loss and wide-band transducer for medical imaging applications. A KLM model based simulation software PiezoCAD was used for acoustic design of the transducer including the front-face matching and backing. The calculated results show that the -6 dB transducer bandwidth can be improved significantly by using double lambda8 matching layers and hard backing. A 4.0 MHz PMN-PT transducer array (with 16 elements) was fabricated and tested in a pulse-echo arrangement. A -6 dB bandwidth of 110% and two-way insertion loss of -46.5 dB were achieved.

Star fruit intoxication successfully treated by charcoal haemoperfusion and intensive haemofiltration

We report on a case of an elderly woman with chronic renal impairment, secondary to diabetic nephropathy, who developed a deep coma and seizure shortly after consumption of star fruit. She was managed in the intensive care unit, and her consciousness level improved dramatically after an 8-hour charcoal haemoperfusion and 30 hours of continuous haemofiltration. There were no long-term neurological or renal sequelae 9 months later. Early recognition of this condition, intensive dialytic therapy and supportive measures, as well as early initiation of charcoal haemoperfusion may improve the management of this potentially treatable condition.

Agreement between initial and final diagnosis of first seizures, epilepsy and non-epileptic events: a prospective study

BACKGROUND

Differentiating between first seizure, epilepsy and a non-epileptic event is a challenging clinical exercise for many physicians as it may lead to different therapeutic implications. This study aims to investigate the agreement between the initial diagnosis at the accident and emergency (A&E) department and the final diagnosis following inpatient neurological evaluation of seizure disorders.

METHOD

A prospective observational study between April 2004 and June 2005 in a regional hospital in Hong Kong recruited 1701 patients from the A&E to neurology/medical wards with initial diagnoses/labels matching any one of 12 predefined keywords which were categorised as either "seizure specific" or "non-specific".

RESULTS

Among the 1170 patients with "non-specific" initial diagnoses/labels, 58 (5%) were finally diagnosed as having had a first seizure or epilepsy. Among 531 patients with "seizure specific" initial diagnoses/labels, 27 (5.1%) were subsequently diagnosed as having had non-epileptic events. The kappa value for agreement between the initial and final diagnosis was 0.88. Of the 154 patients with a final diagnosis of first seizure, 34 (22%) had "non-specific" initial labels. Among these patients, components of the evaluation contributing to revision of diagnosis included retrieval of witness accounts (47%), epileptiform discharges on EEG (47%), short term monitoring in patients suspected of acute symptomatic seizures (28%) and panel discussion of cases (22%).

CONCLUSION

There was generally a high degree of agreement between the initial and final diagnosis, but first seizures were often missed initially. Careful history taking, judicious use of EEG, selective short term monitoring and liaison with specialists are important in reaching an accurate diagnosis.

Ferroelectric domain in PMN-xPT single crystal studied by piezoresponse force microscopy and finite-element analysis

Ferroelectric domain structures in (001)-cut Pb(Mg(1/3)Nb(2/3))O(3)-38%PbTiO(3) and (011)-cut Pb(Mg(1/3) Nb(2/3))O(3)-60%PbTiO(3) single crystals are studied by means of piezoresponse force microscopy (PFM). The out-of-plane- polarization (OPP) and in-plane-polarization (IPP) domain piezoresponse imaging reveals the domain and domain boundary configurations in these two different PbTiO(3)-content crystals. Finite-element analysis is carried out to illustrate the OPP and IPP-PFM imagings mechanism and interpret the domains superposition phenomenon during PFM imaging.

Refractory epilepsy in a Chinese population

OBJECTIVES

To investigate the proportion of Chinese patients with intractable seizures and the risk factors leading to refractory epilepsy.

METHODS

Consecutive patients over 14 years of age attending a Neurology clinic were evaluated. Patients with epilepsy were classified into two groups according to their seizure control: refractory or seizure-free. Epilepsy was classified as idiopathic as defined by age-related onset and typical electroclinical characteristics, symptomatic if secondary to a structural abnormality and cryptogenic if the cause was unknown. Age, sex, epilepsy syndrome classification, aetiology, presence of mental retardation and the number of drugs used were compared between patients with refractory epilepsy and those in remission.

RESULTS

Among 260 adolescent and adult patients with a mean age of 34 years (range 15-79), complete seizure control was achieved in 157 (60%) cases. Multivariate binomial logistic regression analysis showed that patients with mesial temporal sclerosis (OR=7.6, 95% CI 3.53-16.4, p<0.01) and the presence of mental retardation (OR=9.39, 95% CI 3.98-22.12, p<0.01) were more likely to develop pharmacoresistant epilepsy.

CONCLUSION

In adults the underlying aetiology is an important factor as to whether patients develop intractable seizures. Poor control was also associated with the presence of mesial temporal sclerosis and mental retardation.

Prevalence of asymptomatic intracranial atherosclerosis in high-risk patients

We used transcranial Doppler to screen 3,057 patients who had at least one vascular risk factor of hypertension, diabetes, or hyperlipidemia and found 385 (12.6%) had middle cerebral artery stenosis. Elderly, hypertension, diabetes, and hyperlipidemia were associated factors. The prevalence escalated quadratically with increasing number of associated factors: from 7.2% for one, to 29.6% for four associated factors. Asymptomatic middle cerebral artery stenosis is common in patients with vascular risk factors.

A door-to-door survey of intracranial atherosclerosis in Liangbei County, China

We studied 590 asymptomatic villagers aged > or =40 years in Liangbei County in central rural China and found 41 subjects (prevalence 6.9%) with intracranial atherosclerosis. In a multivariate analysis, the significant risk factors for intracranial stenosis were hypertension (OR 2.53; 95% CI 1.12 to 5.72), glycosuria (OR 3; 1.19 to 7.97), heart disease (OR 4; 1.39 to 11.6), and family history of stroke (OR 5.2; 1.38 to 20). Intracranial atherosclerosis is not uncommon among asymptomatic Chinese subjects.

Spontaneous basilar artery dissection

Dissection of the basilar artery is rare. We report a 51-year-old man who developed acute pontine infarction associated with dissection of the distal basilar artery. There was no trauma or unaccustomed movement of the head and neck prior to the stroke. The dissection was diagnosed non-invasively by magnetic resonance imaging and magnetic resonance angiography. Cervicocerebral artery dissection is a common cause of stroke in young patients particularly when conventional cardiovascular risk factors are absent. Magnetic resonance angiography combined with magnetic resonance imaging is a useful diagnostic tool prior to invasive angiography.

Adsorption of copper ion on magnetite-immobilised chitin

The adsorption of Cu2+ from aqueous solution by magnetite-immobilised chitin (MC) was studied in batch mode. Two conventional adsorbents, cation exchange resin (CER) and activated carbon (AC) were used for the comparison. The physicochemical parameters including pH, concentration of adsorbent, temperature and initial Cu2+ concentration were optimised. Under the optimised conditions, the removal efficiencies of Cu2+ for MC, CER and AC were 91.67, 93.36 and 89.16%, respectively. In addition, the removal capacities of Cu2+ for MC, CER and AC were 56.71, 74.84 and 6.55 mg/g, respectively. The adsorption isotherm studies indicated that the adsorptive behaviour of Cu2+ on three adsorbents could be well described by the Langmuir model. The maximum adsorption capacities (qmax) for MC, CER and AC were 53.19, 89.29 and 5.82 mg/g, respectively. The applicability of the kinetic model has been investigated for MC. Experimental results indicated that a pseudo-second-order reaction model provided the best description of the data with a correlation coefficient 0.999 for different initial Cu2+ concentrations. The rate constants were also determined. Various thermodynamic parameters such as standard free energy (DeltaG 0), enthalpy (DeltaH 0) and entropy (DeltaS 0) were calculated for predicting the adsorption nature of MC. The results indicated that this system was a spontaneous and endothermic process.

Prospective randomized, double-blind, placebo-controlled study of pre- and postoperative administration of a COX-2-specific inhibitor as opioid-sparing analgesia in major colorectal surgery

PURPOSE

To demonstrate the opioid-sparing effect and reduction in postoperative ileus obtained with valdecoxib 40 mg administered pre- and postoperatively in patients undergoing colorectal resection.

METHODS

Patients for elective colorectal resection from December 2002 to June 2004 were randomized to receive either valdecoxib or placebo with standard patient-controlled analgesia (PCA) morphine. In the study arm, the first dose of valdecoxib 40 mg was administered orally as close as possible to 1 h prior to the start of surgery. Each subsequent dose was administered at 24-h intervals up to 120 h. Patients in the control arm were served placebos at the same time-points.

RESULTS

Forty patients were enrolled in the study arm and 39 (excluding one protocol violation) in the control arm. The groups were comparable in age, sex, American Society of Anesthesiology status, body mass index, incision length, and duration and types of operations. Mean PCA doses at 12 and 24 h were 18.6 and 28.3 mg in the study arm vs 26.2 and 41.2 mg in controls, representing a one-third opioid reduction. Bowel sound and movement first appeared at medians of 12 and 72 h in the study arm vs 24 and 84 h, respectively, in controls (P < 0.05). Tolerance of solid diet was at a median of 60 h and discharge at a median of 4 days in the study arm vs 72 h and 6 days in controls (P < 0.05 and P < 0.01, respectively). Seven (18%) morbidities occurred in the control vs six (15%) in the study arm.

CONCLUSIONS

Patients treated with a cyclo-oxygenase 2-specific inhibitor have a shorter recovery time when compared with patients on a standard postoperative PCA morphine-only regimen after colorectal resection.

Apolipoprotein E ?4 allele is associated with the volume of white matter changes in patients with lacunar infarcts

The relationship between the apolipoprotein E (APOE) exon 4 polymorphism and white matter changes (WMC) in elderly subjects or patients with Alzheimer's disease is controversial. To investigate this polymorphism in relation to WMC in patients with lacunar infarcts, we prospectively observed 67 patients with acute lacunar infarct and 134 age- and sex-matched controls. Genotypes were determined using a nested polymerase chain reaction. WMC were measured quantitatively and were divided into two groups, severe and mild, with the mean volume of WMC as the cut point. Twenty-two patients (33%) had severe WMC. There was a significant difference in the distribution of APOE epsilon2, epsilon3, and epsilon4 alleles between severe and mild WMC groups (P = 0.002). The frequency of epsilon4 alleles was higher in patients with severe WMC than in those with mild WMC (25% vs. 7%, P = 0.003). These results suggest that APOE epsilon4 may exacerbate WMC in patients with lacunar infarcts. Further studies are required to confirm this finding.

Sublingual misoprostol compared to artificial rupture of membranes plus oxytocin infusion for labour induction in nulliparous women with a favourable cervix at term

OBJECTIVES

To compare the efficacy of labour induction using sublingual misoprostol versus combined artificial rupture of membranes and oxytocin infusion for nulliparous women with a favourable cervix at term.

DESIGN

Open randomised controlled trial.

SETTING

Regional hospital, Hong Kong.

PATIENTS

Fifty nulliparous women with a favourable cervix (Bishop score 6 or more) at term and indications for labour induction.

INTERVENTIONS

With their informed consent, 100 eligible women were to be randomised to receive either sublingual misoprostol 50 micrograms every 4 hours for up to five doses or oxytocin infusion after artificial rupture of membranes. Interim analysis was planned at a sample size of 50.

MAIN OUTCOME MEASURES

Vaginal delivery within 24 hours of induction.

RESULTS

The study was terminated when interim analysis of the first 50 recruits showed that a significantly smaller proportion of misoprostol-treated women delivered vaginally within 24 hours of induction than in the conventional treatment group (68% vs 100%; relative risk, 0.68; 95% confidence interval, 0.51-0.91; P=0.009), although comparable numbers of women eventually delivered vaginally. The mean induction to vaginal delivery interval was 4.5 hours longer in the misoprostol group (P=0.027). After misoprostol treatment, all women went into labour. Forty percent of them delivered without oxytocin. There was no significant difference in uterine hyperstimulation rate, operative delivery rate, and neonatal outcomes. Maternal satisfaction was higher in the misoprostol group (92% vs 60%; relative risk, 1.53; 95% confidence interval, 1.09-2.16; P=0.008).

CONCLUSIONS

Despite being well accepted by women, labour induction using this regimen of sublingual misoprostol is less effective in achieving vaginal delivery within 24 hours.

Association of smoking with increasing vascular involvement in type 2 diabetic Chinese patients

PURPOSE

To identify the relationship between smoking and the metabolic profile and existing vascular disease in Chinese type 2 diabetic patients.

METHODS

1710 diabetic patients were screened for complications, and biochemical and anthropometric vascular risk factors. As most smokers were male, differences were only compared between male current (n = 196) and never smoking patients (n = 300).

RESULTS

The smokers had higher glycosylated haemoglobin levels (8.2 +/- 2.0 vs. 7.6 +/- 1.8%, p < 0.001) than never smokers, despite a greater proportion receiving hypoglycaemic agents (87.5 vs. 79.6%, p = 0.003). Male smokers compared to never smokers had lower HDL-cholesterol levels (1.12 +/- 0.31 vs. 1.20 +/- 0.30 mmol/L, p = 0.006), and elevated albumin-to-creatinine ratio (3.57 [2.68-4.75] vs. 2.47 [1.99-3.05] mg/mmol, p = 0.040). However, diastolic blood pressure was lower in the smoking group (78 +/- 12 vs. 82 +/- 12 mmHg, p = 0.001) even though they received less blood pressure-lowering treatments (23.8 vs. 33.2%, p = 0.034). The prevalence of peripheral vascular disease was increased in the diabetic patients who smoked compared to nonsmokers (7.1 vs. 2.8%, p = 0.039).

CONCLUSIONS

Smoking was associated with a more adverse metabolic profile and peripheral vascular disease. As mainland China undergoes rapid modernisation and urbanisation, the observed effects of smoking means tobacco control becomes increasingly important to prevent or minimise potential health impacts and chronic disease.

Microfabricated discontinuous-edge surface topographies influence osteoblast adhesion, migration, cytoskeletal organization, and proliferation and enhance matrix and mineral deposition in vitro

The fabrication of surfaces that stimulate increased adhesion, migration, and differentiated function of osteoblasts has been viewed as being desirable for many orthopedic applications. Previous studies have shown that microfabricated pits and grooves alter adhesion, spreading, matrix secretion, and production of mineral by rat calvarial osteoblasts (RCOs). The mechanisms underlying these effects are unknown, although microenvironment and cell alignment are considered to play a role. The aim of this work was to investigate the behavior of RCOs on microfabricated discontinuous-edge surfaces (DESs), which could provide an alternative means to control both the microenvironment and cellular alignment. Two types of discontinuous-type structures were employed, gap-cornered boxes and micron scale pillars. DES gap-cornered boxes and the pillars influenced the arrangement of F-actin, microtubules, and vinculin. Osteoblasts were guided in their direction of migration on both types of substrata. Both box DESs and pillars altered the staining intensity and localization pattern of phosphotyrosine and src-activated FAK localization. Cell multilayering, matrix deposition, and mineralization were enhanced on both discontinuous topographies when compared with smooth controls. This study shows that DESs alter adhesion, migration, and proliferative responses from osteoblasts at early time points (<1 week) and promote multilayering, matrix deposition, and mineral deposition at later times (2-6 weeks). Such topographical patterns could potentially be employed as effective surface features on bone-contacting implants or in membrane-based periodontal applications.

Potential Value of Poststroke Extracranial Arterial Blood Flow Volume in the Prediction of Stroke Functional Outcome

BACKGROUND AND PURPOSE

Cerebral vasoreactivity and collateral circulation are important protective mechanisms against cerebral ischemia. Previous studies suggest that the efficiency of these mechanisms can be reflected by extracranial arterial blood flow volume. Brain damage leading to neurological impairments can influence patients' functional recovery after stroke. This study attempted to explore the potential value of post stroke extracranial arterial blood flow volume in the prediction of stroke patients' functional outcome.

METHODS

We prospectively studied 362 consecutive patients who were hospitalized for recent acute strokes. All patients underwent extracranial arterial blood flow volume measurement of the carotid and vertebral arteries by color velocity imaging quantification within 3 days after admission. Their functional recovery was assessed 6 months after stroke. The effect of post stroke extracranial arterial blood flow volume on patients' functional outcome was tested by multivariate ordinal regression after controlling for other independent variables. Significance was at p<0.05.

RESULTS

Post stroke extracranial arterial blood flow volume together with age, pre-stroke modified Rankin scale, the National Institutes of Health Stroke Scale and diabetes mellitus had significant effects on the patients' 6-month functional outcome as measured by the modified Rankin scale after controlling for other independent variables (p<0.05).

CONCLUSIONS

Post stroke extracranial arterial blood flow volume is an independent outcome predictor. The graded predictive power of this parameter is potentially more superior than other outcome predictors by allowing classification of stroke outcome according to the degree of severity. A large prospective study is thus warranted to investigate its clinical value in the management of stroke patients.

Scoring system for empyema thoracis and help in management

OBJECTIVE

To evaluate the implications of a newly defined severity scoring of empyema in children for the prediction of surgical management and to compare the length of hospitalization as an outcome measure of patients treated using medical therapy, salvage video-assisted thoracoscopic surgery (VATS) vs early elective VATS.

METHODS

A retrospective chart review of parapneumonic empyema of patients below 18 years of age admitted to a tertiary children's hospital in northern Taiwan from April 1993 to December 2002 was performed. Patients were categorized into a medical group who received antibiotic therapy, needle aspirations with/without tube thoracostomy; a salvage VATS group when the patients required surgery for the relief of persistent fever > 38 degrees C, chest pains or dyspneic respirations despite initial medical therapy; an early VATS group when the patients received elective surgery early after admission. The demographic data, clinical features, laboratory findings, and duration of hospitalization were compared using a severity score of empyema (SSE).

RESULTS

Streptococcus pneumoniae was the most common infecting organism, followed by Staphylococcus aureus, Pseudomonas aeruginosa. No organisms were recovered in 39% of patients. A pleural pH < 7.1 increases the odds of requiring surgical intervention by 6 times among this cohort. Children who required decortication of empyema had a higher severity score (mean 4.8 vs 3.0, p < 0.005). The duration of hospitalization for patients having early VATS showed a shortening stay (mean 18 vs 28 days) as compared to salvage VATS.

CONCLUSION

A pleural pH < 7.1 and a newly designed clinical severity score of empyema 4 are two predictors of surgical intervention for fibrinopurulent empyema in the present study. Early elective VATS may be adopted not later than 7 days after failure of appropriate antibiotic therapy and adequate drainage of empyema to decrease the length of stay and minimize morbidity.

Appropriate use of personal protective equipment among healthcare workers in public sector hospitals and primary healthcare polyclinics during the SARS outbreak in Singapore

BACKGROUND

Singapore was affected by an outbreak of severe acute respiratory syndrome (SARS) from 25 February to 31 May 2003, with 238 probable cases and 33 deaths.

AIMS

To study usage of personal protective equipment (PPE) among three groups of healthcare workers (HCWs: doctors, nurses, and administrative staff), to determine if the appropriate PPE were used by the different groups and to examine the factors that may determine inappropriate use.

METHODS

A self-administered questionnaire survey of 14,554 HCWs in nine healthcare settings, which included tertiary care hospitals, community hospitals, and polyclinics, was carried out in May-July 2003. Only doctors, nurses, and clerical staff were selected for subsequent analysis.

RESULTS

A total of 10 236 valid questionnaires were returned (70.3% response); 873 doctors, 4404 nurses, and 921 clerical staff were studied. A total of 32.5% of doctors, 48.7% of nurses, and 77.1% of the administrative staff agreed that paper and/or surgical masks were "useful in protecting from contracting SARS". Among this group, 23.6% of doctors and 42.3% of nurses reported working with SARS patients. The view that a paper and/or surgical mask was adequate protection against SARS was held by 33.3% of doctors and 55.9% of nurses working at the A&E unit, 30.5% of doctors and 49.4% of nurses from medical wards, and 27.5% of doctors and 37.1% of nurses from intensive care units. Factors which predicted for agreement that paper and/or surgical masks were protective against SARS, included HCW's job title, reported contact with SARS patients, area of work, and Impact Events Scale scores.

CONCLUSION

A variety of factors determine appropriate use of personal protective equipment by HCWs in the face of a major SARS outbreak.

Storage and release of femtosecond laser pulses in a resonant photonic crystal

Femtosecond laser pulses with suitable pulse areas are shown to decelerate and stop inside a resonant photonic crystal. The release of the stored fields can be achieved through pulse collision by use of an external optical pulse as a control field. The duty cycle efficiency of the storage and release of light is shown to be as much as 96%. The proposed technique is applied to a real photonic system with finite thickness of atomic layers.

Extent of white matter lesions is related to acute subcortical infarcts and predicts further stroke risk in patients with first ever ischaemic stroke

OBJECTIVE

To investigate whether the extent of white matter lesions (WML) on fluid attenuated inversion recovery (FLAIR) MRI sequences is an independent risk factor for recurrent stroke, and to document the pattern of acute cerebral infarcts using diffusion weighted imaging (DWI) in patients with different severities of WML.

METHODS

In a prospective cohort study, 228 consecutive stroke patients were studied between 1999 and 2001 in a community hospital. The severity of WML was graded as 0 (no WML), 1 (mild), 2 (moderate), or 3 (severe) according to the FLAIR appearances. DWI was used to document the location and size of the infarct.

RESULTS

31 patients had grade 0 WML, 69 had grade 1, 59 had grade 2, and 69 had grade 3. Age was independently associated with WML on logistic regression analysis (p = 0.0001). Acute cerebral infarcts in deep white matter were correlated with increasing severity of WML. On a median follow up of 23.0 months, life table analysis showed that recurrent stroke was related to the severity of WML (recurrence rate 7.8% in grade 0, 9.3% in grade 1, 17.7% in grade 2, 43.7% in grade 3; p = 0.0001). Survival was reduced in patients with severe WML (p = 0.0068). A Cox proportional hazards model showed WML to be predictive of recurrent stroke (p = 0.000, hazard ratio = 4.177 (95% confidence interval, 2.038 to 8.564)) and also for survival (p = 0.040, hazard ratio = 2.021 (1.032 to 3.960)).

CONCLUSIONS

Patients with severe leukoaraiosis have increased risk of deep subcortical stroke and a higher risk of recurrent stroke.

Cushing's syndrome in a patient with a corticotropin-releasing hormone-producing pheochromocytoma

OBJECTIVE

To present the first case of Cushing's syndrome attributable solely to ectopic production of corticotropin-releasing hormone by a pheochromocytoma.

METHODS

We summarize the clinical features and results of laboratory investigations in a patient with symptoms characteristic of Cushing's syndrome.

RESULTS

Although Cushing's syndrome is usually caused by ectopic production of adrenocorticotropic hormone (ACTH), our current patient had clinical and biochemical evidence of hypercortisolism in conjunction with "normal" ACTH levels and nonsuppressible serum and urinary cortisol levels on low-dose and high-dose dexamethasone suppression testing. An abdominal computed tomographic scan revealed a 7.7-cm mass in the left adrenal gland. Light microscopic examination and immunohistochemical staining showed a pheochromocytoma with mild cortical hyperplasia. Immunostaining was positive for corticotropin-releasing hormone but negative for ACTH.

CONCLUSION

To our knowledge, this is the first case of Cushing's syndrome in a patient with pheochromocytoma caused only by ectopic secretion of corticotropin-releasing hormone without accompanying secretion of ACTH.

Laparoscopic-assisted colon and rectal surgery - lessons learnt from early experience

INTRODUCTION

Current evidence shows that laparoscopic bowel surgery is associated with a lower incidence of postoperative ileus, lower postoperative pulmonary and wound complication rates, shorter hospital stays and a quicker return to activity than open surgery. This paper aims to report our early experience with laparoscopic-assisted colorectal procedures in our Centre for Advanced Laparoscopic Surgery and the important lessons we have learnt from this.

MATERIALS AND METHODS

All laparoscopic-assisted colon and rectal surgical (LAC) procedures performed between January 2000 and December 2003 were reviewed. Clinical and operative records of these patients were reviewed. Data retrieved included patient demographics, selected intraoperative parameters, and postoperative outcomes. In order to provide a comparable reference, an equal number of matched open procedures over the same period were accrued and similarly analysed. All patients were managed on a standard carepath. All data were entered into a database and analysed using a statistical software package.

RESULTS

Forty-two laparoscopicassisted colorectal procedures were performed from June 2000 to December 2003. A similar number of diagnosis-matched patients with open colorectal procedures were used as comparison. The diagnoses included cancer (68.5% versus 73.8%), diverticulosis (5.7% versus 9.5%) and polyps (14.3% versus 9.5%). Seven were converted to open surgery because of bleeding, adhesions and locally advanced disease. Laparoscopic-assisted procedures performed included 1 right hemicolectomy, 5 left hemicolectomies, 9 anterior resections, 1 abdominal-perineal resection, 3 sigmoid colectomies, 11 colostomies and 1 Hartmann's procedure. Mean perioperative time (146 min versus 125 min, P = 0.173) was comparatively longer. Mean duration for analgesic requirement (2.25 days versus 2.64 days, P = 0.05), mean length of stay (5.31 days versus 9.07 days, P < 0.05), mean time to commencement of diet (2.91 days versus 4.05 days, P < 0.001) and mean time to first bowel movement (2.57 days versus 4.10 days, P < 0.001) were all comparatively shorter. General morbidity rates (17.1% versus 21.4%, P = 0.35) were lower. No local wound complications were found in our laparoscopic-assisted group. Patients who had undergone open surgery instead of the planned laparoscopic-assisted procedures fared more poorly.

CONCLUSIONS

Laparoscopic-assisted colorectal procedures performed in well-selected patients are associated with shorter hospital stays, quicker return of bowel function and lower morbidity when compared to the matched open procedures. Early experience should be acquired from performing technically simple procedures in patients with benign conditions before progressing to definitive resections in those with cancer.

Electrophysiological, clinical and epidemiological study of Guillain–Barré Syndrome in Hong Kong Chinese

The authors reviewed the clinical and electrophysiological features in 20 consecutive adult patients with Guillain-Barre Syndrome (GBS) admitted to a regional hospital in Hong Kong from 1993 to 1998. The majority of cases in this locality consists of the demyelinating form of GBS; epidemic, acute motor axonal neuropathy is not the predominant form. The incidence of GBS in this region of China was 0.44 per 100,000.

Clinical characteristics of tuberculosis in children in the north of Taiwan

Tuberculosis (TB) in children is an endemic and sometimes life-threatening disease in Taiwan. This study analyzed the clinical characteristics of a total of 112 children with TB managed in a referral children's hospital in the north of Taiwan between 1998 and 2002. The diagnosis of TB was made by either a positive result of culture, acid-fast stain, histopathology, or polymerase chain reaction (PCR). Tuberculin skin test was positive (indurations > or =10 mm) in 73% of 63 patients tested. The male-to-female ratio was 0.93 (54/58), and the mean age was 10.7 years. Thirty one percent of children were younger than 6 years of age, 12% were 6 to 12 years old, and 57% were older than 12 years. Fifty percent (50/100) of these children had household members with TB; 29.2% (31/106) were aboriginal; 93% had received Bacille Calmette-Guerin (BCG) vaccine. Isolated pulmonary TB was diagnosed in 65 cases (58%), extrapulmonary TB in 25 (22%), and combined intra- and extrapulmonary TB in 22 (20%). Fever was not a presenting symptom in 30.4% of children, was low grade (<38.5 degrees C) in 23.2% and was high grade (> or =38.5 degrees C) in 46.4%. The mean duration of fever was 13.9 days. Patients with combined intra- and extrapulmonary TB had a significantly longer hospital stay (p<0.001), a higher peak body temperature (p<0.001), and a longer duration of fever (p=0.024). Patients with extrapulmonary TB had a significantly lower incidence of fever (p=0.001), a lower segment count (p=0.007) and a lower serum C-reactive protein level (p=0.019). Ventriculoperitoneal shunt insertion was performed in 8 of 12 cases with central nervous system involvement. Among 21 cases of TB osteomyelitis, tibia (33%) and spine (33%) were the most common sites of involvement. The overall mortality rate was 3.6% (4/112). Extrapulmonary TB and combined intra- and extrapulmonary TB were more commonly seen in children with a younger age and in those who had not received BCG vaccination. This study found that household members with TB history and aboriginal ethnicity were strongly associated with TB in Taiwanese children. Multidrug-resistant TB was uncommon in children born before the year 2003.

ATRA therapy restores normal renal function and renal reserve and prevents renal failure

This article presents clinical data which suggest that the current dosage of losartan 50 to 100 mg/day may not be the optimum in many cases, especially if used as monotherapy in the treatment of proteinuria and we may have to increase to 200 mg/day. However, about 30% of patients cannot take angiotensin-converting enzyme inhibitor (ACEI) because of the side effect of cough. To potentiate the anti-proteinuric effect of losartan, especially for patients who do not adhere to a low salt diet, a 12.5-mg dose of hydro-chlorothiazide may further decrease proteinuria. The main message of this article is that we would have to, in many instances, increase the dose of losartan to a minimum of 100 mg/day or 100 mg twice a day for some patients for optimal therapy. The second message is to monitor the creatinine clearance test (CCT) and to start therapy when CCT is reduced and not wait for serum creatinine to rise to abnormal levels (renal impairment) before starting therapy. The first group involves half a dozen patients with hypertension but no proteinuria. Therapy with losartan is shown to improve the renal function. This data suggest that losartan, apart from its use in reduction of proteinuria, can be used in patients with mild renal impairment without proteinuria to reverse the mild renal impairment and preserve renal function. The second group deals with 3 patients with low creatinine clearance. After a followup period of an average of 3 years, they all developed renal impairment. In another 6 patients, the data suggest that we should perhaps treat patients with low CCT as soon as possible and with dose ranging from 100 to 200 mg/day if necessary, to derive maximum beneficial effect. The third group highlights 5 patients with high CCT due to glomerular hyperfiltration. With time, the high CCT decreases and renal impairment sets in. The data suggest that patients with high CCT should be treated early to prevent renal impairment. The fourth group illustrates 6 patients where their proteinuria was markedly reduced with the increase of losartan from 100 mg/day to 200 mg/day, suggesting that losartan 200 mg/day is probably the optimum dose. In conclusion, apart from its traditional usage in reduction of proteinuria to retard progression to renal failure, the data suggest that losartan is also indicated in patients with renal impairment in the absence of proteinuria; patients with low CCT, patients with high CCT and patients who do not respond to a dosage of 100 mg/day should have the dosage increased to 100 mg twice daily to increase efficacy of losartan. It is hoped that with these new and earlier indications as well as increased dosage of losartan starting with 100 mg, whenever possible, and increasing to 200 mg/day, if there is no response, we can prevent more patients from developing renal failure. Based on these observations, further randomised controlled trials should be designed to address these issues.

Multiple acute cerebral infarcts on diffusion-weighted imaging and risk of recurrent stroke

Multiple acute cerebral infarcts (MACIs) detected by diffusion-weighted imaging (DWI) may indicate an unstable source of thromboembolism. The authors studied 119 consecutive acute ischemic stroke patients within 24 hours of onset with DWI. MACIs were present in 20 patients (16.8%). During the follow-up period, there were 15 recurrent strokes, 3 acute coronary syndromes, and 5 deaths. MACI was the only significant independent predictor for vascular events and death (odd ratio [OR]] = 4.34; p = 0.001) and stroke recurrence (OR = 5.93; p = 0.001).

Albuminuria is a marker of increasing intracranial and extracranial vascular involvement in Type 2 diabetic Chinese patients

AIMS/HYPOTHESIS

Albuminuria has been reported to be a marker of cardiovascular risk factors and disease morbidity and mortality, but its relationship with intracerebral atherosclerotic disease is less clear. The aim of this study was to investigate the association between albuminuria and intracranial and extracranial vascular involvement in Chinese Type 2 diabetic patients.

METHODS

The anthropometric and fasting biochemical measurements of 966 Type 2 diabetic patients with normoalbuminuria (55.6%), microalbuminuria (27.7%) or macroalbuminuria (16.7%) were compared. The prevalence of microvascular and macrovascular disease and middle cerebral artery (MCA) stenosis, measured by transcranial Doppler ultrasound, were also compared between the groups.

RESULTS

Albuminuria was closely associated with a range of adverse parameters, including high BP, dyslipidaemia, smoking and adiposity (all p<0.01). The prevalence of microvascular disease (retinopathy p<0.001) and macrovascular disease (peripheral vascular disease p=0.012, myocardial infarction, p=0.004, MCA stenosis p<0.001) increased significantly with increasing levels of albuminuria. Albuminuria was also found to be an independent predictor of microvascular and macrovascular disease.

CONCLUSIONS/INTERPRETATION

Albuminuria was an independent predictor of increasing levels of vascular risk factors and microvascular and macrovascular disease in this group of Type 2 diabetic patients, and a possible role for albuminuria as a marker of intracranial cerebrovascular disease should be further investigated.

Consensus statement on ischaemic stroke care in Hong Kong

OBJECTIVE

To issue guidelines for the care of acute stroke in Hong Kong, with the target audience of all health care professionals who are involved in acute stroke care.

PARTICIPANTS

The Hong Kong Neurological Society and the Hong Kong Stroke Society.

EVIDENCE

The panel applied the 'rule of evidence' used by the United States Agency for Health Care Policy and Research. When there is insufficient evidence, the recommendation was based on customary practice and was circulated among the members and fellows of the two societies before coming to a consensus.

CONSENSUS PROCESS

Group meetings were held in 2002 to review the literature about acute care for patients with ischaemic stroke and to issue a consensus statement with reference to the local health care system. Participants of the meetings were appointed by the councils of The Hong Kong Neurological Society and the Hong Kong Stroke Society. The draft statement was circulated among the members and fellows of the two societies for comments before it was finalized.

CONCLUSIONS

Ischaemic stroke is a heavy health care burden to Hong Kong. The current consensus statement provides a framework to establish a multidisciplinary approach towards its acute management.

Long-term outcome of carpal tunnel syndrome after conservative treatment

The purpose of this study was to investigate the long-term prognosis of patients with carpal tunnel syndrome (CTS). We prospectively followed-up patients with CTS for 80 weeks. Thirty cases had been treated with a single injection of methylprednisolone acetate and another 30 with a 10-day course of prednisolone. At the end of the follow-up period, there were no significant differences in symptoms as measured by global symptom score and in the proportion of patients who progressed to decompressive surgery. Few patients who were not operated on (11.4%) remain asymptomatic.

Cognitive impairment and functional outcome after stroke associated with small vessel disease

OBJECTIVES

Although stroke associated with small vessel disease (SSVD) can induce both motor and cognitive impairment, the latter has received less attention. We aimed to evaluate the frequency of the varying severity levels of cognitive impairment, the determinants of severe cognitive impairment, and the association of cognitive impairment with functional outcome after SSVD.

METHODS

Consecutive patients admitted to hospital because of SSVD were assessed at 3 months after stroke. We performed a semi-structured clinical interview to screen for cognitive symptoms. Severity of cognitive symptoms was graded according to the Clinical Dementia Rating Scale (CDR). Performance on psychometric tests (Mini-Mental State Examination, Alzheimer's Disease Assessment Scale (cognition subscale), Mattis Dementia Rating Scale (initiation/perseverence subscale; MDRS I/P)) of patients of different CDR gradings was compared with that of 42 healthy controls. Basic demographic data, vascular risk factors, stroke severity (National Institute of Health Stroke Scale; NIHSS), pre-stroke cognitive decline (Informant Questionnaire on Cognitive Decline in the Elderly; IQCODE), functional outcome (Barthel index; BI), Instrumental Activities Of Daily Living; IADL), and neuroimaging features (site of recent small infarcts, number of silent small infarcts, white matter changes) were also compared among the groups. Regression analyses were performed to find predictors of severe cognitive impairment and poor functional outcome.

RESULTS

Among the 75 included patients, 39 (52%) complained of cognitive symptoms. The number of patients in each CDR grading was as follows: 39 (52%) had a CDR of 0, 26 (34.7%) had a CDR of 0.5, 10 (13.3%) had a CDR of > or =1. Pre-stroke IQCODE and previous stroke predicted CDR> or =1. The NIHSS was associated with more impaired BI. The NIHSS and MDRS I/P contributed most to impaired IADL.

CONCLUSIONS

Half of the patients with SSVD complained of varying severity of cognitive problems 3 months after stroke. Pre-stroke cognitive decline and previous stroke predict severe cognitive impairment post stroke. Stroke severity and executive dysfunction contribute most to a poor functional outcome.

Efficacy of preemptive analgesia for wound pain after laparoscopic operations in infertile women: a randomised, double-blind and placebo control study

OBJECTIVE

To compare preemptive analgesia and preclosure analgesia in reducing wound pain after laparoscopic operation.

DESIGN

Randomised, double-blind and placebo control.

SETTING

University referral centre.

POPULATION

Infertile women undergoing diagnostic laparoscopy with or without additional procedures.

METHODS

One hundred and forty-four women were randomised to receive 10 mL of 1% lignocaine at the surgical sites before incision and 10 mL of normal saline before closure of incision (the preemptive group), saline before incision and lignocaine before closure of incision (the preclosure group) and saline at the surgical sites both before incision and closure of incision (the placebo group).

MAIN OUTCOME MEASURES

Post-operative wound pain measured by linear visual analogue scale and amount of analgesic use.

RESULTS

The women in the preclosure group had significantly lower pain scores at 2, 4 and 24 hours than those in the placebo group, whereas the women in the preemptive group only showed significantly lower pain scores at 2 hours than the placebo group. The pain score at 24 hours in the preclosure group was significantly lower than that in the preemptive group. There was no significant difference in the post-operative analgesic requirement among the three groups.

CONCLUSION

The preclosure analgesia is better than preemptive analgesia and no analgesia in reducing post-operative wound pain.

MARS therapy in critically ill patients with advanced malignancy: a clinical and technical report

BACKGROUND/METHODS

Molecular Adsorbent Recirculating System (MARS) was used in three consecutive critically ill patients at the Singapore General Hospital with advanced malignancy and acute liver failure (ALF). Case 1 was a male patient with hepatocellular carcinoma (HCC) for which initial right hepatectomy was followed by left hepatectomy 5 months later for recurrent HCC. The postoperative course following second surgery was complicated by severe methicillin-resistant Staphylococcus aureus (MRSA) sepsis, mild azotaemia and subacute cholestatic liver failure. MARS was used thrice in this patient. Case 2 was a female patient with advanced acute lymphoblastic leukaemia (ALL) with post bone marrow transplantation (BMT) acute haemolytic-uraemic syndrome (HUS) secondary to cyclosporin A (Cy A), cytomegalovirus (CMV) infection, severe nosocomial pneumonia, acute renal failure (ARF) treated with continuous haemofiltration and acute veno-occlusive disease resulting in Budd-Chiari syndrome. The latter precipitated ALF. MARS was instituted twice. Case 3 was a male patient with advanced, refractory Hodgkin's disease previously treated with multiple courses of chemotherapy. ALF developed secondary to acute viral hepatitis B flare. He was given a trial of MARS once in the ICU. All the three patients eventually died.

RESULTS

Mean MARS intradialytic systemic pressures were as follows: systolic pressure range was 95 +/- 17 to 128 +/- 17 mmHg and diastolic pressure range was 51 +/- 5 to 67 +/- 7 mmHg. Pressure at albumin dialysate exit point from dialyser 1 (Ae) ranged from 253 +/- 11 to 339 +/- 15 mmHg and that at albumin dialysate entry point into dialyser 1 (Aa) ranged from 142 +/- 11 to 210 +/- 6 mmHg. Ultrafiltration (UF) was 633 +/- 622 mL over mean treatment duration of 6.3 +/- 0.9 h with a total heparin dose of 1583 +/- 817 IU. Coagulation status pre- and 6-h post-MARS was similar: aPTT (P=0.116) and platelet count (P=0.753). There were no bleeding complications or circuit thromboses. MARS had a significant de-uraemization effect (pre- and post-MARS serum creatinine and urea: P=0.046 and 0.028, respectively) but did not significantly attenuate blood lactate, ammonia or total bilirubin levels. Albumin dialysate (Ae - Aa) urea and creatinine concentrations appeared to be sharply attenuated after 6 h of MARS. In contrast, the removal of total bilirubin by albumin dialysate from the blood compartment appeared to plateau after 4 h of continuous MARS operation.

CONCLUSIONS

MARS was well-tolerated in critically ill patients with advanced and complicated cancer. Low-dose heparin was safe and did not compromise MARS circuit integrity. Although MARS had a significant de-uraemization effect, this appeared to be limited by the duration of MARS operation. Our data suggested that such a limit was reached earlier for total bilirubin. More data are needed to confirm the present findings and further delineate the saturation limit of MARS for different toxins that accumulate in ALF. This would affect the optimal duration of MARS therapy.

Plaque Volume Measurement by Magnetic Resonance Imaging as an Index of Remodeling of Middle Cerebral Artery: Correlation with Transcranial Color Doppler and Magnetic Resonance Angiography

BACKGROUND

The feasibility of a noninvasive evaluation of remodeling of the middle cerebral artery (MCA) by magnetic resonance imaging (MRI) was assessed. The results were correlated with magnetic resonance angiography (MRA) and transcranial color Doppler (TCD) findings.

METHODS

26 patients (13 male and 13 female, age ranged from 46 to 82 years) who presented with symptoms of cerebrovascular accidents had TCD, MRA and MRI assessment of the MCA. The TCD and MRA findings of 40 MCAs accessible by TCD were correlated with the ratio of cross-sectional area of the vessel (VA), luminal area of the vessel (LA) and plaque load (PL).

RESULTS

The VA ratio and LA showed no correlation with TCD or MRA results. PL however was shown to be associated with both TCD and MRA.

CONCLUSIONS

MRI could be used to assess remodeling in MCAs. PL was found to be associated with TCD and MRA findings.

Status epilepticus in Hong Kong Chinese: aetiology, outcome and predictors of death and morbidity

The majority of patients with epilepsy live in developing countries but there is limited information on status epilepticus (SE) from these regions. We evaluated the clinical profile and predictors of poor outcome in a group of Chinese patients with SE. Patients with SE were ascertained from the medical, intensive care and emergency departments of a large urban hospital from 1996 to 2001. Factors for poor outcome, defined as death or morbidity as measured by deterioration in functional status using the Glasgow Outcome Score were analysed in a multivariate logistic regression model. A total of 107 episodes of SE occurring in Chinese patients were studied. The three most common underlying causes were cerebrovascular disease, metabolic derangement and anti-convulsant withdrawal but alcohol-related SE was infrequent. Twenty-six percent had worsened functional ability and the mortality rate was 16%. Predictors of poor outcome were older age (odds ratio (OR)=1.04, 95% CI 1.01-1.07), delay in treatment (OR=3.52, 95%CI 1.01-12.18), SE due to cerebrovascular disease (OR=9.73, 95% CI 1.58-59.96) and CNS infection (OR=30.27, 95% CI 3.14-292.19).

Hyperintense middle cerebral artery sign using MRI

AIM

To assess whether the presence of the hyperintense middle cerebral artery (MCA) sign, detected using magnetic resonance imaging (MRI), has any prognostic value in subacute infarction. The results were also compared with computed tomography (CT).

MATERIALS AND METHODS

Twenty-five consecutive patients with suspected subacute ischaemic stroke (6-48 h after onset of symptoms) underwent MRI and CT assessment. The incidence of intraluminal thrombus demonstrated by conventional T1 and T2-weighted images was assessed. The results were correlated with National Institutes of Health Stroke Scale (NIHSS).

RESULTS

Hyperintense MCA was identifiable on T1-weighted images in 77.8% patients, on T2-weighted images in 61.1% patients, and in 38.9% patients using CT. Patients with intraluminal thrombus identified by MRI had more severe stroke (mean NIHSS of 12.2+/-8.0 versus 4+/-3.2 respectively, p=0.003).

CONCLUSIONS

The presence of hyperintense MCA by MRI is associated with higher NIHSS and may therefore have a prognostic value.

B0 images obtained from diffusion-weighted echo planar sequences for the detection of intracerebral bleeds

BACKGROUND AND PURPOSE

To evaluate the accuracy of B0 echo planar imaging (EPI) sequences for the detection of intracerebral bleeds.

METHODS

One hundred patients with acute strokes had magnetic resonance imaging and computed tomography (CT) examinations performed within 48 hours after the onset of symptoms. The detectability of intracerebral bleeds by the B0 EPI sequences was assessed. The results were compared to the gradient echo (GRE) sequence and CT brain examinations. The results of the GRE sequences were used as the gold standard.

RESULTS

The B0 EPI sequences detected 11 out of 11 acute, intracerebral hematomas; 6 out of 8 acute hemorrhagic strokes; 2 out of 2 acute, intraventricular hemorrhages; 8 out of 8 old hemorrhagic infarcts; 1 out of 1 subarachnoid hemorrhages; and 11 out of 22 patients with microbleeds. For the detection of acute, intracerebral hematomas and acute, hemorrhagic infarcts, B0 EPI sequences had a sensitivity of 89.5%, a specificity of 100%, and an accuracy of 98%. CT had a sensitivity of 57.9%, a specificity of 100%, and an accuracy of 92%. B0 EPI sequences did not miss any acute or chronic hemorrhages detected by CT examinations.

CONCLUSIONS

B0 EPI sequences could not replace GRE images for the detection of both acute and chronic hemorrhages. Their sensitivity for the detection of acute and chronic blood products, however, was comparable, if not superior, to that of CT examinations.

Renal impairment in patients with multiple myeloma

OBJECTIVES

To determine the incidence of multiple myeloma in the Eastern District of Hong Kong Island, the degree of renal impairment at presentation, and its relationship with haematological and biochemical parameters and survival.

DESIGN

Retrospective study.

SUBJECTS AND METHODS

Patients with myeloma who were admitted to a regional hospital in Hong Kong from January 1994 to March 2000 were included. Demographic data, type and stage of multiple myeloma, degree of renal impairment, haematological and biochemical parameters, and survival data were analysed.

RESULTS

There were 64 patients (28 male, 36 female) in the study. The incidence rate for multiple myeloma in this group was 1.78 per 100 000 population. Immunoglobulin G (53.1%) was the most common type of multiple myeloma seen, followed by immunoglobulin A (29.7%), light-chain (12.5%), and immunoglobulin D (4.7%). Nineteen (29.7%) patients had serum creatinine levels of greater than 177 micro mol/L at presentation. Renal impairment was more common in patients with light-chain multiple myeloma (P=0.081). The serum creatinine level was not significantly correlated with haemoglobin level (r= -0.21), platelet count (r=0.04), serum calcium level (r=0.08), or albumin level (r= -0.03). The median survival time for patients with multiple myeloma was 592 days (95% confidence interval, 229-955). Serum creatinine level at presentation was significantly associated with survival (P=0.017). Patients with a creatinine level of less than 400 micromol/L had longer survival (P=0.042). Infection was the most common cause of death (32.8%).

CONCLUSION

The incidence rate noted was comparable to other published studies. Renal impairment at presentation was common in patients with multiple myeloma and was associated with poor survival.

Asymptomatic microbleeds as a risk factor for aspirin-associated intracerebral hemorrhages

The authors measured the presence and extent of asymptomatic microbleeds on gradient-recalled-echo MRI in 21 aspirin users who developed intracerebral hemorrhage and 21 aspirin users without history of intracerebral hemorrhage. Microbleeds were more frequent (19 vs 7, p < 0.001) and more extensive (mean number of microbleeds 13.3 vs 0.4, p < 0.001) in the intracerebral hemorrhage group than in the control group. Asymptomatic microbleeds may be a risk factor for aspirin-associated intracerebral hemorrhage.

Role of magnetic resonance imaging for preoperative evaluation of patients with refractory epilepsy

OBJECTIVE

To investigate the magnetic resonance imaging characteristics of patients with refractory epilepsy and the relationship to progression to surgery.

DESIGN

Prospective observational study.

SETTING

University teaching hospital, Hong Kong.

PATIENTS

Patients undergoing preoperative evaluation for epilepsy surgery.

MAIN OUTCOME MEASURE

Cranial magnetic resonance imaging findings, correlation with electroencephalographic results, and percentage of patients who were considered suitable candidates for surgery.

RESULTS

Structural abnormalities associated with refractory epilepsy in 100 consecutive patients were mesial temporal sclerosis (30%), neocortical sclerosis (23%), vascular malformation (7%), neuronal migration disorders (7%), and tumours (5%). Normal brain scans were found for 28% of patients. Fourteen of 30 (46%) patients with medial temporal lobe lesions at magnetic resonance imaging were suitable candidates for surgery compared with 8/42 (19%) patients with extrahippocampal lesions (odds ratio=3.7; 95% confidence interval, 1.3-10.6; P<0.012).

CONCLUSION

Mesial temporal sclerosis was the most common pathology in patients with refractory epilepsy. At the Prince of Wales Hospital, for patients who have undergone a basic magnetic resonance imaging protocol and surface electroencephalography, the result of cranial magnetic resonance imaging is an important determinant for whether patients will undergo surgery.

Clinical and radiographic spectrum of septic pulmonary embolism

AIMS

To review the clinical presentation, radiographic findings, and outcome of therapy in children with septic pulmonary embolism.

METHODS

Retrospective analysis of patients in a tertiary paediatric facility in northern Taiwan.

RESULTS

Ten children were identified with septic pulmonary emboli in a four year retrospective chart review between 1998 and 2001. Seven were immunocompetent, two were premature infants, one had beta thalassemia major. Seven had community acquired staphylococcal infections and bacteraemia, of which six were methicillin resistant Staphylococus aureus (MRSA) isolates. Five had soft tissue infections, two bone infections, one suppurative otitis media, one catheter related infection, and one unknown foci of infection. Multiple and bilateral nodular pulmonary parenchymal lesions were common on plain chest radiographs, but chest computed tomography scans showed the additional findings of a "vessel sign" and central cavitations, confirming the existence of septic pulmonary embolism.

CONCLUSIONS

Community acquired MRSA infections occurred in seven patients with septic pulmonary embolism but without predisposing high risk factors. Critically ill children with skin, soft tissue, or bone infections, when associated with septic pulmonary embolism in an area with a high rate of MRSA, should be empirically treated with glycopeptides (such as vancomycin or teicoplanin) before susceptibility results are known, in order to minimise morbidity and avoid mortality.

Sonographic characterisation of radiation-induced carotid artery stenosis

BACKGROUND AND PURPOSE

To study the distribution, extent and sonographic characterisation of radiation-induced carotid artery stenosis in nasopharyngeal carcinoma (NPC) patients.

METHODS

The distribution of plaques, the extent of stenosis, and the sonographic characterisation of the plaque at maximum stenosis were recorded in 71 NPC patients. The results were compared with the ultrasound results of a control group of 142 patients presenting with symptoms of cerebrovascular disease or carotid bruit.

RESULTS

NPC patients had a higher incidence of carotid stenosis (77 vs. 50.7%). The common carotid arteries were most commonly affected by radiation-induced stenosis (93/142 vs. 37/284 in the control group), whereas the carotid bulb was the most commonly affected (56/284) site in the control group. Significantly more NPC patients had moderate-to-severe stenosis (21/71 vs. 27/142). Analysis of the sonographic appearance of radiation-induced and atherosclerotic plaques showed more diffuse involvement in the post-radiation group. Non-calcified plaques and intraplaque hypoechoic foci were also more frequent in the post-radiation group.

CONCLUSIONS

Radiation-induced carotid stenosis is more diffuse in distribution, is associated with more severe luminal stenosis and has different sonographic plaque characterisation compared with carotid stenosis without radiation exposure.

Discriminatory sonographic criteria for the diagnosis of carpal tunnel syndrome

OBJECTIVE

Sonographic examination of the median nerve has been suggested as a useful alternative to electrophysiologic study in the diagnosis of carpal tunnel syndrome. To determine its usefulness and the best diagnostic criterion, sonograms of patients with the disease were compared with sonograms of healthy subjects in a case-control study.

METHODS

Patients with carpal tunnel syndrome and asymptomatic controls who were matched for age and sex were enrolled and underwent sonography of the wrists. Eight separate sonographic criteria were analyzed in each wrist. Data from the patient group and the control group were compared to establish optimal diagnostic criteria for carpal tunnel syndrome, using receiver operating characteristic analytic techniques.

RESULTS

Thirty-five patients with carpal tunnel syndrome and 35 asymptomatic controls were examined. Increased cross-sectional area of the median nerve was found to be the most predictive measure of carpal tunnel syndrome, proximal to the tunnel inlet, at the tunnel inlet, and at the tunnel outlet, with significant differences between patients and controls. Using a receiver operating characteristic curve, a cut-off value >0.098 cm(2) at the tunnel inlet provided a diagnostic sensitivity of 89% and a specificity of 83%.

CONCLUSION

Sonographic measurement of the median nerve cross-sectional area is both sensitive and specific for the diagnosis of carpal tunnel syndrome.

Carotid intima-media thickness in patients with head and neck irradiation for the treatment of nasopharyngeal carcinoma

AIM

Intima-media thickness (IMT) has been shown to be useful in the evaluation and monitoring of carotid artery atherosclerosis in patients at risk of cardiovascular events. In this study, we aimed to examine the IMT in patients with nasopharyngeal carcinoma (NPC) who received irradiation to the carotid arteries during radiotherapy, and compared them with a control group.

MATERIALS AND METHODS

Fifty-one NPC patients (aged between 39 and 69 years) and a group of 51 age-and sex-matched controls were studied by ultrasound. The IMT at the far wall of the common carotid artery was measured three times and the average value taken in each subject. The IMT of both groups were compared. Risk factors for IMT thickness, including hypertension, smoking, hyperglycaemia, hypercholesterolaemia, history of cerebrovascular accidents and cardiovascular disease, were also studied.

RESULTS

The mean carotid IMT of patients in the NPC group (2.2+/-1.5 mm) was statistically greater than that in normal controls (0.7+/-0.15 mm) (P < 0.05). There was no statistically significant difference between the IMT in the right and left common carotid arteries within each group of patients.

CONCLUSION

The findings suggest that patients with irradiation have increased arterial IMT. As they are asymptomatic the clinical relevance is not clear.

Incidence of carotid stenosis in nasopharyngeal carcinoma patients after radiotherapy

BACKGROUND

Radiation-induced carotid stenosis in patients with head and neck tumors can cause significant mortality and morbidity. This study examined the incidence of stenosis in the extracranial carotid arteries of nasopharyngeal carcinoma patients after radiotherapy.

METHODS

The extracranial carotid arteries of 71 (53 male and 18 female; mean age of 53.6 years) postradiation patients with nasopharyngeal carcinoma were examined with color Doppler ultrasound. The distribution of the arterial stenosis and the degree of stenosis were documented. The results were compared with the control group, which comprised 51 newly diagnosed nasopharyngeal carcinoma patients (35 male and 16 female, mean age of 48.8 years) before radiotherapy. Incidences of risk factors for arterial stenosis such as hypertension, smoking, and hypercholesterolemia also were studied in these two groups.

RESULTS

There was no significant difference in the incidence of risk factors between the two groups. Arterial stenosis was, however, more common in the postradiation group than the preradiation group (56 of 71 vs. 11 of 51). The common/internal carotid arteries (CCA/ICA) were most commonly involved (55 of 71 vs. 11 of 51; P < 0.01), followed by the external carotid artery (ECA) (32 of 71 vs. 1 of 51; P < 0.01) and vertebral artery (VA; 5 of 71 vs. 0; P = 0.069). Significant stenosis (> 50% reduction of luminal diameter) was only found in the postradiation group (21 of 71 in CCA/ICA, 11 of 71 in ECA, 4 of 71 in VA).

CONCLUSIONS

This study showed that radiation could cause significant carotid stenosis. Ultrasound examinations for these patients therefore are necessary for early detection and possible intervention of this late radiation-induced complication.

Bridging bronchus in an infant demonstrated by direct coronal computed tomography and three-dimensional rendering display

Bridging bronchus is a rare anomaly in which the right lower lobe bronchus arises from the left main bronchus and bridges the lower mediastinum. The first reported case was diagnosed at autopsy in 1976. The second reported case was diagnosed by bronchography confirmed at autopsy in 1980. We describe a 9-month-old infant with such an anomaly. Our patient presented with cough, shortness of breath, and rhinorrhea with no fever or sputum production. The physical examination revealed only coarse breath sound and chest retraction with no other abnormalities. Chest radiography showed decreased lung volume and shifting of the mediastinum to the left. Diagnosis of this anomaly was not possible with computed tomography (CT) axial imaging. Direct coronal CT and 3D rendering with the surface-shaded display technique showed a small right upper lobe bronchus and proximal stenotic left main bronchus, with the intermediate bronchus originating from the left main bronchus and crossing the midline to enter the contralateral lung.

The nurse specialist role in Hong Kong: perceptions of nurse specialists, doctors and staff nurses

AIM

The purpose of this study is to review and delineate the impact in terms of the perceived importance as well as the role components of nurse specialists in Hong Kong.

RATIONALE

The Nurse Specialist Scheme was launched in 1994 in Hong Kong. Studies in the West showed that there were impacts on the roles of other members among the health care team. However, minimal local published work has been carried out in reviewing the scheme.

DESIGN

The design of the study was nonexperimental. Data were collected by self-administered questionnaires. The questionnaire adopted was developed by O'Mullan (1995), and the five roles studied were administration, clinical practice, consultation, education and research. To ensure the contextual relevancy and consistency of the questionnaire, content validity and test-retest reliability tests were performed. The content validity index was 0.85 and the test-retest reliability (Spearman's rho coefficient) ranged from 0.57 to 0.97. Subjects were obtained by stratified convenience sampling technique. The ratios for subject selection among the doctors, ward managers, nursing officers and registered nurses were 3:1:3:10, respectively. Because of the small numbers for nurse specialists, they were all included in the study. The final sample consisted of 11 nurse specialists, 47 ward managers, 56 nursing officers, 110 registered nurses and 15 doctors (n=239).

RESULTS

The results showed that there were significant differences in the perceptions of importance of the administration, clinical practice, education and research roles, and the frequency of occurrence of the clinical practice and research roles. This was further verified by the Fisher's Least Significant Differences (LSD) test.

CONCLUSIONS

A regulatory system of the nurse specialist was recommended to monitor the development of the nurse specialist role and practice and to ensure the safety of the public with regard to the emerging role. Both the implications and limitations are discussed.