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.