ESTIMATION OF PEDIATRIC DOSE DESCRIPTORS ADAPTED TO INDIVIDUAL SPECIFIC SIZE FROM CT EXAMINATIONS.

Clinical challenges in pediatrics dose estimation by the displayed computed tomography (CT) dose indices may lead to inaccuracy, and thus size-specific dose estimate (SSDE) is introduced for better-personalized dose estimation. This study aims to estimate pediatric dose adapted to specific size. This retrospective study involved pediatric population aged 0-12 y. SSDE was derived from scanner reported volume CT dose index (CTDIvol), based on individual effective diameter (Deff) with corresponding size correction factors. The correlations of Deff with other associated factors such as age, exposure setting, CTDIvol and SSDE were also studied. The average Deff of Malaysian pediatric was smaller than reference phantom size (confidence interval, CI = 0.28, mean = 14.79) and (CI = 0.51, mean = 16.33) for head and abdomen, respectively. These have led to underestimation of pediatric dose as SSDE was higher than displayed CTDIvol. The percentage differences were statistically significant (p < .001) ranged from 0 to 17% and 37 to 60% for head and abdominal CT, respectively. In conclusion, the clinical implementation of SSDE in pediatric CT imaging is highly relevant to reduce radiation risk.

Influence of postural changes on haemodynamics in internal carotid artery bifurcation aneurysm using numerical methods.

Cerebral intracranial aneurysms are serious problems that can lead to stroke, coma, and even death. The effect of blood flow on cerebral aneurysms and their relationship with rupture are unknown. In addition, postural changes and their relevance to haemodynamics of blood flow are difficult to measure in vivo using clinical imaging alone. Computational simulations investigating the detailed haemodynamics in cerebral aneurysms have been developed in recent times not only to understand the progression and rupture but also for clinical evaluation and treatment. In the present study, the haemodynamics of a patient-specific case of a large aneurysm on the left side internal carotid bifurcation (LICA) and no aneurysm on the right side internal carotid bifurcation (RICA) was investigated. The simulation of these patient-specific models using fluid-structure interaction provides a valuable comparison of flow behavior between normal and aneurysm models. The influences of postural changes were investigated during standing, sleeping, and head-down (HD) position. Significant changes in flow were observed during the HD position and quit high arterial blood pressure in the internal carotid artery (ICA) aneurysm model was established when compared to the normal ICA model. The velocity increased abruptly during the HD position by more than four times (LICA and RICA) and wall shear stress by four times (LICA) to ten times (RICA). The complex spiral flow and higher pressures prevailing within the dome increase the risk of aneurysm rupture.

OPTIMIZATION OF RADIATION DOSE IN CT IMAGING: ESTABLISHING THE INSTITUTIONAL DIAGNOSTIC REFERENCE LEVELS AND PATIENT DOSE AUDITING.

The aim of this study was to propose local diagnostic reference levels (LDRLs) for the most common computed tomography (CT) examinations (including contrast and non-contrast scan phase) performed at Advanced Medical and Dental Institute (AMDI), Universiti Sains Malaysia (USM), Malaysia. A retrospective CT dose survey of 1488 subjects from January 2015 until December 2018 was performed at AMDI USM, Malaysia. The proposed DRLs were established at 50th and 75th percentile of dose distribution for all dose metrics (CT dose index [CTDI]; CTDIvol, CTDIw and dose-length product). The proposed LDRLs were compared with national DRLs and other established DRLs. The 10 most common CT examinations at AMDI were thorax-abdomen-pelvis (TAP) CT (46%), followed by pelvis CT (17%), abdomen-pelvis CT (10%), brain/head CT (9%) and other CT protocols. The local DRLs were established using the third quartile values of dose distribution and were categorized based on CT region protocols. Most of the proposed DRLs were exceeded the national DRLs (63%) and other international DRLs (67%). From the dose auditing, almost half of the recent dose data (for year 2018) exceeded the proposed local DRLs and the unusual dose were observed in TAP, brain/head and pelvis CT examinations. The unusual higher dose could be due to higher mAs settings, higher number of scan phase for contrast study and higher pitch factor. The local DRLs should be established for dose optimization and reduction of the occurrence of excessive radiation exposure to the patients. The establishment of the Ads and LDRLs should also consider all the factors that affect the variation in DRLs such as CT technology, scanning protocols and population characteristics. The local dose distribution should always be revised for improvement of the current local practice.

Efficacy of Oral Mixed Tocotrienols in Diabetic Peripheral Neuropathy: A Randomized Clinical Trial.

Importance: Management of painful diabetic peripheral neuropathy remains challenging. Most therapies provide symptomatic relief with varying degrees of efficacy. Tocotrienols have modulatory effects on the neuropathy pathway and may reduce neuropathic symptoms with their antioxidative and anti-inflammatory activities. Objective: To evaluate the efficacy of oral mixed tocotrienols for patients with diabetic peripheral neuropathy. Design, Setting, and Participants: The Vitamin E in Neuroprotection Study (VENUS) was a parallel, double-blind, placebo-controlled trial that recruited participants from January 30, 2011, to December 7, 2014, with 12 months of follow-up. This trial screened 14 289 patients with diabetes from 6 health clinics and ambulatory care units from 5 public hospitals in Malaysia. A total of 391 patients who reported neuropathic symptoms were further assessed with Total Symptom Score (TSS) and Neuropathy Impairment Score (NIS). Patients 20 years or older with a TSS of 3 or higher and an NIS of 2 or higher were recruited. Interventions: Patients were randomized to receive 200 mg of mixed tocotrienols twice daily or matching placebo for 12 months. Patients with hyperhomocysteinemia (homocysteine level ≥2.03 mg/L) received oral folic acid, 5 mg once daily, and methylcobalamin, 500 µg thrice daily, in both groups. Main Outcomes and Measures: The primary outcome was patient-reported neuropathy TSS (lancinating pain, burning pain, paresthesia, and asleep numbness) changes at 12 months. The secondary outcomes were NIS and sensory nerve conduction test result. Results: Of 391 eligible patients, 300 were recruited (130 [43.3%] male; mean [SD] age, 57.6 [8.9] years; mean [SD] duration of diabetes, 11.4 [7.8] years) and 229 (76.3%) completed the trial. The TSS changes between the tocotrienols and placebo groups at 12 months (-0.30; 95% CI, -1.16 to 0.56; P = .49) were similar. No significant differences in NIS (0.60; 95% CI, -1.37 to 2.65; P = .53) and sensory nerve conduction test assessments were found between both groups. In post hoc subgroup analyses, tocotrienols reduced lancinating pain among patients with hemoglobin A1C levels greater than 8% (P = .03) and normohomocysteinemia (homocysteine level <2.03 mg/L; P = .008) at 1 year. Serious adverse events in both groups were similar, except more infections were observed in the tocotrienols group (6.7% vs 0.7%, P = .04). Results reported were of modified intention-to-treat analyses. Conclusions and Relevance: Supplementation of oral mixed tocotrienols, 400 mg/d for 1 year, did not improve overall neuropathic symptoms. The preliminary observations on lancinating pain among subsets of patients require further exploration. Trial Registration: National Medical Research Registry Identifier: NMRR-10-948-7327 and clinicaltrials.gov Identifier: NCT01973400.

Investigation of mass attenuation coefficient of almond gum bonded Rhizophora spp. particleboard as equivalent human tissue using XRF technique in the 16.6-25.3 keV photon energy.

This paper reports the novel use of almond gum as a binder in manufacturing Rhizophora spp. particleboard. X-ray fluorescence spectroscopy was employed for analysis under photon energy range of 16.6-25.3 keV. Results showed that almond gum-bonded Rhizophora spp. particleboard can be used as tissue-equivalent phantom in diagnostic radiation. The calculated mass attenuation coefficients of the particleboards were consistent with the values of water calculated using XCOM program for the same photon energies, with p values of 0.056, 0.069, and 0.077 for samples A8, C0, and C8, respectively. However, no direct relationship was found between the percentage of adhesive and the mass attenuation coefficient. The results positively supported the use of almond gum as a binding agent in the fabrication of particleboards, which can be used as a phantom material in dosimetric and quality control applications.

Erratum to: Diagnostic Performance of (68)Ga-DOTATATE PET/CT, (18)F-FDG PET/CT and (131)I-MIBG Scintigraphy in Mapping Metastatic Pheochromocytoma and Paraganglioma.

[This corrects the article DOI: 10.1007/s13139-015-0339-z.].

Erratum to: Diagnostic Performance of (68)Ga-DOTATATE PET/CT, (18)F-FDG PET/CT and (131)I-MIBG Scintigraphy in Mapping Metastatic Pheochromocytoma and Paraganglioma.

[This corrects the article DOI: 10.1007/s13139-015-0331-7.].

Diagnostic Performance of (68)Ga-DOTATATE PET/CT, (18)F-FDG PET/CT and (131)I-MIBG Scintigraphy in Mapping Metastatic Pheochromocytoma and Paraganglioma.

PURPOSE: To evaluate the diagnostic performance of (68)Ga-DOTATATE (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET)/computed tomography (CT), (18)F-FDG PET/CT and (131)I-MIBG scintigraphy in the mapping of metastatic pheochromocytoma and paraganglioma. MATERIALS AND METHODS: Seventeen patients (male = 8, female = 9; age range, 13-68 years) with clinically proven or suspicious metastatic pheochromocytoma or paraganglioma were included in this prospective study. Twelve patients underwent all three modalities, whereas five patients underwent (68)Ga-DOTATATE and (131)I-MIBG without (18)F-FDG. A composite reference standard derived from anatomical and functional imaging findings, along with histopathological information, was used to validate the findings. Results were analysed on a per-patient and on per-lesion basis. Sensitivity and accuracy were assessed using McNemar's test. RESULTS: On a per-patient basis, 14/17 patients were detected in (68)Ga-DOTATATE, 7/17 patients in (131)I-MIBG, and 10/12 patients in (18)F-FDG. The sensitivity and accuracy of (68)Ga-DOTATATE, (131)I-MIBG and (18)F-FDG were (93.3 %, 94.1 %), (46.7 %, 52.9 %) and (90.9 %, 91.7 %) respectively. On a per-lesion basis, an overall of 472 positive lesions were detected; of which 432/472 were identified by (68)Ga-DOTATATE, 74/472 by (131)I-MIBG, and 154/300 (patient, n = 12) by (18)F-FDG. The sensitivity and accuracy of (68)Ga-DOTATATE, (131)I-MIBG and (18)F-FDG were (91.5 %, 92.6 % p < 0.0001), (15.7 %, 26.0 % p < 0.0001) and (51.3 %, 57.8 % p < 0.0001) respectively. Discordant lesions were demonstrated on (68)Ga-DOTATATE, (131)I-MIBG and (18)F-FDG. CONCLUSIONS: Ga-DOTATATE PET/CT shows high diagnostic accuracy than (131)I-MIBG scintigraphy and (18)F-FDG PET/ CT in mapping metastatic pheochromocytoma and paraganglioma.

Alpha shape theory for 3D visualization and volumetric measurement of brain tumor progression using magnetic resonance images.

Resection of brain tumors is a tricky task in surgery due to its direct influence on the patients' survival rate. Determining the tumor resection extent for its complete information via-à-vis volume and dimensions in pre- and post-operative Magnetic Resonance Images (MRI) requires accurate estimation and comparison. The active contour segmentation technique is used to segment brain tumors on pre-operative MR images using self-developed software. Tumor volume is acquired from its contours via alpha shape theory. The graphical user interface is developed for rendering, visualizing and estimating the volume of a brain tumor. Internet Brain Segmentation Repository dataset (IBSR) is employed to analyze and determine the repeatability and reproducibility of tumor volume. Accuracy of the method is validated by comparing the estimated volume using the proposed method with that of gold-standard. Segmentation by active contour technique is found to be capable of detecting the brain tumor boundaries. Furthermore, the volume description and visualization enable an interactive examination of tumor tissue and its surrounding. Admirable features of our results demonstrate that alpha shape theory in comparison to other existing standard methods is superior for precise volumetric measurement of tumor.

Clinical determinants of fluorodeoxyglucose positron emission tomography/computed tomography in differentiated thyroid cancer patients with elevated thyroglobulin and negative (131)iodine whole body scans after (131)iodine therapy.

BACKGROUND: A cross-sectional prospective study has been conducted on differentiated thyroid cancer (DTC) patients using negative (131)Iodine ((131)I) whole body scans and elevated thyroglobulin (Tg) levels. The main objective of this research was to determine the prevalence of the conversion of differentiated to dedifferentiated thyroid cancer patients during follow up at the Hospital Kuala Lumpur. It has been demonstrated that fluorodeoxyglucose (FDG) uptake is inversely proportional to the iodine concentration and to differentiation of the cells. METHODS: Thirty-five patients with histologically proven DTC that have undergone total or near total thyroidectomy, and post (131)I radioactive iodine ablation therapy, were selected and prospectively analysed. The patients also had to show at least one negative whole body scan and Tg levels of 10 µg/L and above. The results of the FDG-Positron Emission Tomography/Computed Tomography (PET/CT) were then studied to determine the association and the predictors influencing the outcome by using univariable and multivariable analyses. RESULTS: Out of the thirty-five patients, 60% of them (twenty-one) showed positive results and 40% (fourteen) showed negative. Age, gender, and type of histopathology (HPE) showed significant associations with the positive results of the FDG-PET/CT. The results also showed no correlations observed between the Tg levels and standardised uptake value (SUV)max in the DTC patients with positive disease findings in the FDG-PET/CT. The predictor for this study was age. CONCLUSION: The prevalence of the conversion of differentiated to dedifferentiated thyroid cancer among patients with negative (131)I and elevated Tg was 60%, with age as the predictor. DTC patients aged 45 year-old and older were seven times more likely to have positive results of FDG-PET/CT imaging.

Clinical investigation of the protective effects of palm vitamin E tocotrienols on brain white matter.

BACKGROUND AND PURPOSE: Previous cell-based and animal studies showed mixed tocotrienols are neuroprotective, but the effect is yet to be proven in humans. Thus, the present study aimed to evaluate the protective activity of mixed tocotrienols in humans with white matter lesions (WMLs). WMLs are regarded as manifestations of cerebral small vessel disease, reflecting varying degrees of neurodegeneration and tissue damage with potential as a surrogate end point in clinical trials. METHODS: A total of 121 volunteers aged ≥35 years with cardiovascular risk factors and MRI-confirmed WMLs were randomized to receive 200 mg mixed tocotrienols or placebo twice a day for 2 years. The WML volumes were measured from MRI images taken at baseline, 1 year, and 2 years using a validated software and were compared. Fasting blood samples were collected for full blood chemistry investigation. RESULTS: According to per-protocol (88 volunteers) and intention-to-treat (121 volunteers) analyses, the mean WML volume of the placebo group increased after 2 years, whereas that of the tocotrienol-supplemented group remained essentially unchanged. The mean WML volume change between the 2 groups was not significantly different (P=0.150) at the end of 1 year but was significant at the end of 2 years for both per-protocol and intention-to-treat analyses (P=0.019 and P=0.018). No significant difference was observed in the blood chemistry parameters between the 2 groups. CONCLUSIONS: Mixed tocotrienols were found to attenuate the progression of WMLs. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT00753532.

Computer-aided segmentation system for breast MRI tumour using modified automatic seeded region growing (BMRI-MASRG).

In this paper, an automatic computer-aided detection system for breast magnetic resonance imaging (MRI) tumour segmentation will be presented. The study is focused on tumour segmentation using the modified automatic seeded region growing algorithm with a variation of the automated initial seed and threshold selection methodologies. Prior to that, some pre-processing methodologies are involved. Breast skin is detected and deleted using the integration of two algorithms, namely the level set active contour and morphological thinning. The system is applied and tested on 40 test images from the RIDER breast MRI dataset, the results are evaluated and presented in comparison to the ground truths of the dataset. The analysis of variance (ANOVA) test shows that there is a statistically significance in the performance compared to the previous segmentation approaches that have been tested on the same dataset where ANOVA p values for the evaluation measures' results are less than 0.05, such as: relative overlap (p = 0.0002), misclassification rate (p = 0.045), true negative fraction (p = 0.0001) and sum of true volume fraction (p = 0.0001).

Tocotrienols for normalisation of hepatic echogenic response in nonalcoholic fatty liver: a randomised placebo-controlled clinical trial.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is one of the commonest liver disorders. Obesity, insulin resistance, lipid peroxidation and oxidative stress have been identified amongst the possible hits leading to the onset and progression of this disease. Nutritional evaluation of NAFLD patients showed a lower-than-recommended intake of vitamin E. Vitamin E is a family of 8 isoforms, 4 tocopherols and 4 tocotrienols. Alpha-tocopherol has been widely investigated in liver diseases, whereas no previous clinical trial has investigated tocotrienols for NAFLD. Aim of the study was to determine the effects of mixed tocotrienols, in normalising the hepatic echogenic response in hypercholesterolaemic patients with ultrasound-proven NAFLD. METHODS: Eighty-seven untreated hypercholesterolaemic adults with ultrasound-proven NAFLD were enrolled and randomised into control group (n = 44) and tocotrienols group (n = 43). The treatment, either mixed tocotrienols 200 mg twice daily or placebo, had a 1-year duration.Normalisation of hepatic echogenic response, being the trial primary aim, was used in sample size calculations. The data were assessed according to intention to treat principle as primary outcome. Per protocol analysis was also carried out as secondary outcome measurement. RESULTS: Thirty and 34 participants concluded the study in the tocotrienols and placebo group respectively. Alpha-tocopherol levels were within the normal range for all subjects. As primary outcome, the normalisation of hepatic echogenic response was significantly higher for the tocotrienols treated group compared to the placebo group in the intention to treat analysis (P = 0.039; 95% CI = 0.896-6.488). As secondary objective, the per protocol assessment also showed significant rate of remission (P = 0.014; 95% CI = 1.117-9.456). Worsening of NAFLD grade was recorded in two patients in the placebo group, but none in the group treated with tocotrienols. No adverse events were reported for both groups. CONCLUSION: This is the first clinical trial that showed the hepatoprotective effects of mixed palm tocotrienols in hypercholesterolemic adults with NAFLD.

Computer aided detection of breast density and mass, and visualization of other breast anatomical regions on mammograms using graph cuts.

Breast cancer mostly arises from the glandular (dense) region of the breast. Consequently, breast density has been found to be a strong indicator for breast cancer risk. Therefore, there is a need to develop a system which can segment or classify dense breast areas. In a dense breast, the sensitivity of mammography for the early detection of breast cancer is reduced. It is difficult to detect a mass in a breast that is dense. Therefore, a computerized method to separate the existence of a mass from the glandular tissues becomes an important task. Moreover, if the segmentation results provide more precise demarcation enabling the visualization of the breast anatomical regions, it could also assist in the detection of architectural distortion or asymmetry. This study attempts to segment the dense areas of the breast and the existence of a mass and to visualize other breast regions (skin-air interface, uncompressed fat, compressed fat, and glandular) in a system. The graph cuts (GC) segmentation technique is proposed. Multiselection of seed labels has been chosen to provide the hard constraint for segmentation of the different parts. The results are promising. A strong correlation (r = 0.93) was observed between the segmented dense breast areas detected and radiological ground truth.

Automatic white matter lesion segmentation using an adaptive outlier detection method.

White matter (WM) lesions are diffuse WM abnormalities that appear as hyperintense (bright) regions in cranial magnetic resonance imaging (MRI). WM lesions are often observed in older populations and are important indicators of stroke, multiple sclerosis, dementia and other brain-related disorders. In this paper, a new automated method for WM lesions segmentation is presented. In the proposed method, the presence of WM lesions is detected as outliers in the intensity distribution of the fluid-attenuated inversion recovery (FLAIR) MR images using an adaptive outlier detection approach. Outliers are detected using a novel adaptive trimmed mean algorithm and box-whisker plot. In addition, pre- and postprocessing steps are implemented to reduce false positives attributed to MRI artifacts commonly observed in FLAIR sequences. The approach is validated using the cranial MRI sequences of 38 subjects. A significant correlation (R=0.9641, P value=3.12×10(-3)) is observed between the automated approach and manual segmentation by radiologist. The accuracy of the proposed approach was further validated by comparing the lesion volumes computed using the automated approach and lesions manually segmented by an expert radiologist. Finally, the proposed approach is compared against leading lesion segmentation algorithms using a benchmark dataset.

Wavelet energy-guided level set-based active contour: a segmentation method to segment highly similar regions.

This paper introduces an approach to perform segmentation of regions in computed tomography (CT) images that exhibit intra-region intensity variations and at the same time have similar intensity distributions with surrounding/adjacent regions. In this work, we adapt a feature computed from wavelet transform called wavelet energy to represent the region information. The wavelet energy is embedded into a level set model to formulate the segmentation model called wavelet energy-guided level set-based active contour (WELSAC). The WELSAC model is evaluated using several synthetic and CT images focusing on tumour cases, which contain regions demonstrating the characteristics of intra-region intensity variations and having high similarity in intensity distributions with the adjacent regions. The obtained results show that the proposed WELSAC model is able to segment regions of interest in close correspondence with the manual delineation provided by the medical experts and to provide a solution for tumour detection.

Diagnostic cerebral angiography in spontaneous intracranial haemorrhage: a guide for developing countries.

OBJECTIVE: Spontaneous intracranial haemorrhage constitutes 18-40% of all stroke cases. Indications for cerebral angiography to find underlying potentially treatable vascular abnormalities are not clear. This study determined which intracranial haemorrhage patients need cerebral angiography by correlating computed tomography (CT) findings, age and hypertension history with cerebral angiography findings. METHODS: A total of 54 patients (8-79 years) with intracranial haemorrhage who underwent both CT examination and six-vessel cerebral angiography were studied over a 2-year period. Cerebral angiography was repeated within 6 weeks if the first angiogram was negative. RESULTS: Angiography detected vascular lesions in 50% of cases (aneurysm 38.9% and arteriovenous malformation, AVM, 11.1%). In the aneurysm group, angiographic yield was 34.3% whereas in the AVM group, it was 37.9%. Subarachnoid haemorrhage (SAH) combined with other types of haemorrhage (such as intracerebral haemorrhage, ICH) was not significantly correlated with the likelihood of finding a vascular lesion, both aneurysm and AVM (p = 0.157). Age less than 50 years had significant correlation (p = 0.021) in the AVM group as well as in the aneurysm group (p < 0.001). A history of hypertension was associated with both aneurysm (p = 0.039) and AVM (p = 0.008). No patients with deep intracerebral haematoma had vascular lesions. The presence of an intravascular haemorrhage (IVH) had significant correlation with aneurysm (p = 0.008) but not AVM. There was no significant difference in mean age between patients with and without a vascular lesion (p = 0.134). CONCLUSION: Cerebral angiography is justified in patients with ICH accompanied by pure SAH (p = 0.001). Other factors associated with finding a vascular lesion were a history of hypertension and the presence of IVH. Diagnostic cerebral angiography is indicated for patients with ICH and SAH and IVH with a history of hypertension, regardless of age.

Perforation of oesophagus and aorta by an unusual migratory fish bone: case report.

This report describes a migratory fish bone which was not found during 1st surgery causing perforation to the superior part of the arch of aorta. The patient presented with feeling of something stucked in her throat after eating fish subsequently followed by progressive excruciating pain in the neck. During 2nd surgery the fish bone was found to have migrated from the superior aspect of the arch of aorta to the anterolateral aspect of the arch of aorta after piercing the aortic lumen. We report a case of migratory fish bone which was not found during 1st surgery. The clinical examination of the throat revealed no foreign body. The CT scan of the neck and upper thorax demonstrated a 1cm linear foreign body part of which had perforated into the superior part of the arch of aorta with mediastinal hematoma. The most likely cause was a fish bone. The patient's condition slowly deteriorated, median sternotomy and exploration of mediastinum then followed. Unfortunately no fish bone was found and only mediastinal hematoma was discovered. After the first operation the patient condition did not improve and repeat CT scan of the neck and upper thorax was done 3 days later. A similar foreign body has now moved from the superior aspect of the arch of aorta to the anterolateral aspect of arch of aorta. Exploration was done again and this time the fish bone was found.

Analysis of pediatric subdural empyema outcome in relation to computerized tomography brain scan.

A cross-sectional study was conducted to predict the outcome in patients with subdural empyema, using initial and post-treatment CT scan brain parameters. Data collection was done on those children who were diagnosed to have subdural empyema by CT scan of the brain with contrast, who underwent burrhole evacuation, from February 2000 until April 2002. Numerous factors, such as coma or loss of unconsciousness at diagnosis, age, types of antibiotic, microbiology, extension of empyema, associated cerebral infarction and ventriculitis, were analyzed. Poor prognosis was associated with loss of consciousness, and hypodensity by CT scan at presentation (p < 0.005). Patients with an extensive subdural empyema will have a good outcome if they are treated early and aggressively with antibiotics and burrhole evacuation.

The incidence of post-operative deep vein thrombosis in general surgical patients of hospital universiti sains malaysia.

The incidence of deep vein thrombosis is believed to be rare in Asians. During recent years, a few reports have appeared with high incidence in orthopaedic patients comparable to Western studies. This study was carried out to find out the incidence of post-operative deep vein thrombosis (DVT) after major surgical procedures in general surgical patients in an Asian population. In a prospective study of 45 consecutive Asian patients after major general surgery, colour-flow duplex scan of the legs as an initial screening was done twice within two weeks. Mean age of the patients was 54 years 5 months and 87% of patients were included in the moderate and high risk group for deep vein thrombosis. Ascending venography was used to confirm deep vein thrombosis on patients with equivocal or positive results from colour flow duplex scan. One patient showed positive evidence of post-operative deep vein thrombosis on colour flow duplex scan which was further confirmed by ascending venography; giving an incidence of 2.2%. The incidence of post-operative deep vein thrombosis in general surgical patients is lower than the Western studies.