Financial development and energy consumption nexus in Malaysia: A multivariate time series analysis

Despite a bourgeoning literature on the existence of a long-run relationship between energy consumption and economic growth, the findings have failed to establish clearly the direction of causation. A growing economy needs more energy, which is exacerbated by growing population. Evidence suggests that financial development can reduce overall energy consumption by achieving energy efficiency. Economic growth and energy consumption in Malaysia have been rising in tandem over the past several years. The three public policy objectives of Malaysia are: economic progress, population growth and financial development. It is of interest to the policymakers to understand the dynamic interrelation among the stated objectives. The paper implements Auto Regressive Distributed Lag (ARDL) approach to cointegration to examine the existence of a long-run relationship among the series: energy consumption, population, aggregate production, and financial development for Malaysia; and tests for Granger causality within the Vector Error Correction Model (VECM). The results suggest that energy consumption is influenced by economic growth and financial development, both in the short and the long-run, but the population-energy relation holds only in the long run. The findings have important policy implications for balancing economic growth vis-à-vis energy consumption for Malaysia, as well as other emerging nations.Financial development; Energy consumption; ARDL; Economic growth

Frequency of severity of disability in patients with grade iII lumbar neural foraminal stenosis on magnetic resonance imaging

Background Low back pain is a common condition and carries substantial socioeconomic implications. Magnetic resonance imaging (MRI) is the imaging modality of choice with lumbar neural foraminal stenosis being one of the most common causes of lower back pain syndromes. Studies have shown a lack of correlation between patients\u27 severity of disability and radiologically determined nerve root constriction. Therefore, the goal of this study will be to determine the frequency of severity of disability in patients with severe (i.e., grade III) lumbar neural foraminal stenosis on MRI to ascertain the impact of MRI diagnosis on clinical outcomes. Materials and methods Two hundred fifty patients of either gender with a history of backache referred for MRI were included by purposive sampling. Of these 250 patients, 27 patients had grade II lumbar neural foraminal stenosis, and 21 had grade I neural foraminal stenosis on MRI and were excluded. Thirty-two patients had a spinal infection (e.g., tuberculosis), and 24 patients had a history of trauma. Further, 31 patients were having follow-up scans for previously diagnosed lumbar neural foraminal stenosis. Hence, after excluding these cases, 115 patients were enrolled in this cross-sectional study with grade III lumbar neural foraminal stenosis on MRI. Results The mean age was 51 years (range: 20 to 82 years). Most of the patients (55.6%) were older than 50 years. The most common site of grade III lumbar neural foraminal stenosis was L4-L5 (56.5%). According to the Oswestry disability index, 47 patients (40.9%) had a severe disability, 32 (27.8%) had a moderate disability, 16 (13.9%) were diabled, 14 (12.2%) had a mild disability, and six (5.2%) were bedridden. Conclusions While MRI is the imaging modality of choice in degenerative lumbar spinal stenosis, clinical disabilities can be more extensive than what radiological findings may indicate in approximately 40% of the cases. Therefore, lumbar spinal stenosis should be a neuro-radiological diagnosis, and surgical decisions should be based on clinical scenarios in addition to MRI findings

Portal biliopathy

Portal biliopathy (PB) is a rare disorder, which mostly presents as sub-clinically. It occurs most commonly due to idiopathic extrahepatic portal vein obstruction. We present three cases having features of portal biliopathy secondary to portal hypertension. Our first case did not have a prior history of chronic liver disease while next two patients had previous history of chronic liver disease resulting in portal hypertension. Cavernous transformation of the portal vein due to extrahepatic portal vein obstruction is not infrequent but biliary obstruction in association with this disorder is distinctly uncommon. Proper case management is very important as prolonged biliary duct obstruction can lead to the development of ascending cholangitis or later on secondary biliary cirrhosis

Magnetic resonance spectroscopy in focal brain lesions

OBJECTIVE: To describe the spectrum of Magnetic Resonance spectroscopy in focal brain lesions and determine its diagnostic accuracy using histopathology as gold standard in differentiating neoplastic and non-neoplastic focal brain lesions. METHODS: The study was conducted in Department of Radiology, Aga Khan University Hospital, Karachi from Dec 2006 till Jan 2009. Fifty three patients found to have focal brain lesions on magnetic resonance imaging (MRI) were included in the study. Magnetic Resonance spectroscopy (MRS) was performed in these focal lesions. These lesions were deemed neoplastic and non-neoplastic on MR Spectrum findings. Correlation of all these findings was done with histopathology obtained in all these patients. Sensitivity, specificity, positive, negative predictive values and diagnostic accuracy of MR Spectroscopy was calculated. Percentage agreement between spectroscopy and histopathology was also calculated using kappa statistics. RESULTS: Increase Choline/creatine and Choline/NAA ratio noted in neoplastic lesions compared to nonneoplastic lesion with significant p-value. MR Spectroscopy has a sensitivity of 93.02%, specificity of 70%, positive predictive value of 93.02%, negative predictive value of 70% and diagnostic accuracy of 88.67% in differentiating neoplastic and non-neoplastic brain lesions. Kappa statistics shows a good agreement between MR Spectroscopy and histopathology (k = 0.630). CONCLUSION: Magnetic Resonance spectroscopy (MRS) is non-invasive sensitive, however, relatively nonspecific modality in differentiating neoplastic and non-neoplastic brain lesions. This modality should be considered as an adjunct to conventional imaging rather than replacement for histopathological evaluation

Financial development and energy consumption nexus in Malaysia: A multivariate time series analysis

Despite a bourgeoning literature on the existence of a long-run relationship between energy consumption and economic growth, the findings have failed to establish clearly the direction of causation. A growing economy needs more energy, which is exacerbated by growing population. Evidence suggests that financial development can reduce overall energy consumption by achieving energy efficiency. Economic growth and energy consumption in Malaysia have been rising in tandem over the past several years. The three public policy objectives of Malaysia are: economic progress, population growth and financial development. It is of interest to the policymakers to understand the dynamic interrelation among the stated objectives. The paper implements Auto Regressive Distributed Lag (ARDL) approach to cointegration to examine the existence of a long-run relationship among the series: energy consumption, population, aggregate production, and financial development for Malaysia; and tests for Granger causality within the Vector Error Correction Model (VECM). The results suggest that energy consumption is influenced by economic growth and financial development, both in the short and the long-run, but the population-energy relation holds only in the long run. The findings have important policy implications for balancing economic growth vis-à-vis energy consumption for Malaysia, as well as other emerging nations

Financial development and energy consumption nexus in Malaysia: A multivariate time series analysis

Despite a bourgeoning literature on the existence of a long-run relationship between energy consumption and economic growth, the findings have failed to establish clearly the direction of causation. A growing economy needs more energy, which is exacerbated by growing population. Evidence suggests that financial development can reduce overall energy consumption by achieving energy efficiency. Economic growth and energy consumption in Malaysia have been rising in tandem over the past several years. The three public policy objectives of Malaysia are: economic progress, population growth and financial development. It is of interest to the policymakers to understand the dynamic interrelation among the stated objectives. The paper implements Auto Regressive Distributed Lag (ARDL) approach to cointegration to examine the existence of a long-run relationship among the series: energy consumption, population, aggregate production, and financial development for Malaysia; and tests for Granger causality within the Vector Error Correction Model (VECM). The results suggest that energy consumption is influenced by economic growth and financial development, both in the short and the long-run, but the population-energy relation holds only in the long run. The findings have important policy implications for balancing economic growth vis-à-vis energy consumption for Malaysia, as well as other emerging nations

Diffusion Weighted MR Imaging of Ring Enhancing Brain Lesions

Objective: To evaluate the role of diffusion weighted imaging in differentiating the cause of ring enhancing brain lesions. Study Design: Analytical, descriptive study. Place and Duration of Study: Department of Radiology, The Aga Khan University Hospital, Karachi, from March 2007 to July 2011. Methodology: Diffusion weighted imaging (DWI) was performed on 37 patients having ring enhancing lesions on their post-contrast brain MRI scans. These lesions were characterized into neoplastic and abscess cavity on the basis of diffusion restriction. Correlation of all these findings was done with histopathology obtained in all these patients. Sensitivity, specificity, positive and negative predictive values and diagnostic accuracy of DWI were calculated. Comparisons of mean ADC values of abscess and neoplastic lesions were also done using t-test. Results: DWI had a sensitivity of 94.73%, specificity of 94.44%, positive predictive value of 94.73%, and negative predictive value of 94.44% and diagnostic accuracy of 94.5% in differentiating brain abscess from neoplastic brain lesions. Mean ADC value in central cavity and wall of neoplastic lesions and brain abscesses were calculated with significant p-value of 0.001 and 0.025 respectively. Conclusion: Diffusion weighted imaging is non-invasive method with high sensitivity and specificity which can help in differentiation of ring enhancing neoplastic lesions and brain abscesses. This modality should be read in conjunction with conventional imaging

Role of multidetector computed tomography (MDCT) in patients with ovarian masses

Objective:To evaluate the diagnostic accuracy of multidetector 64-slice computed tomography (MDCT) in the diagnosis and differentiation of benign and malignant ovarian masses using histopathology and surgical findings as the gold standard. Material And Methods: This study was conducted in Aga Khan University Hospital, Karachi, Pakistan. Data was reviewed retrospectively from 1 November 2008 to 12 December 2009. One hundred Patients found to have ovarian masses on CT scan were included in the study. CT scan was performed in all these Patients after administration of oral and IV contrast. Ovarian masses were classified as benign and malignant on scan findings. Imaging findings were compared with histopathologic results and surgical findings. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of MDCT were calculated. Results: MDCT was found to have 97% sensitivity, 91% specificity, and an accuracy of 96% in the differentiation of benign and malignant ovarian masses, while PPV and NPV were 97% and 91%, respectively. Conclusion: MDCT imaging offers a safe, accurate and noninvasive modality to differentiate between benign and malignant ovarian masses

Diagnostic accuracy of digital mammography in the detection of breast cancer

Introduction Breast cancer has a high prevalence in the community and places very high demands on resources. Digital mammography provides a good quality image with reduced radiation dose and can detect breast carcinoma in its earlier stages, resulting in good prognosis and improved patient survival. Objective To calculate the diagnostic accuracy of digital mammography in the detection of breast cancer, using histopathology as a gold standard in women aged over 30 years, who are undergoing mammography for screening and diagnostic purposes. Materials and methods This was a cross-sectional analytical study, conducted in the department of radiology, for a total duration of 10 months. A total of 122 patients of age above 30 years, referred for digital mammography for the evaluation of different symptoms related to breast diseases, followed by biopsy/surgery and histopathology, were included in the study. Result Our data confirmed that digital mammography is a highly accurate tool for breast cancer detection having a sensitivity of 97%, a specificity of 64.5%, a positive predictive value of 89%, and a negative predictive value of 90.9%, with a diagnostic accuracy of 89.3%. Conclusion Considering our results, we recommend that digital mammography should replace screen-film mammography as a basic tool to detect breast cancer for both screening and diagnostic purpose

Triphasic computed tomography (CT) scan in focal tumoral liver lesions

OBJECTIVE: To assess the diagnostic accuracy of triphasic spiral CT in differentiating benign from malignant focal tumoral liver lesions. METHODS: The study was conducted in Department of Radiology of Aga Khan University Hospital and Sind Institute of Urology and Transplantation, Karachi from Feb 2006 to Feb 2007. By convenient sampling, 45 patients found to have focal tumoral liver lesions were recruited for one year period and their triphasic CT scans findings were evaluated and later correlated with histopathology. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of triphasic CT scan were calculated. RESULTS: Among 45 patients, 136 liver lesions (11 benign and 125 malignant) were detected with the help of different enhancement patterns. Out of these, 37(82.2%) patients had malignant while 8 (17.8%) had benign lesions. On later histopathological examination, 35 (77.8%) of the total 45 cases had malignant lesions while 10 (22.2%) were diagnosed as benign lesions. Based on these results, it could be assessed that triphasic CT Scan has a sensitivity of 100%, specificity of 80%, positive predictive value of 94.5%, negative predictive value of 100% and diagnostic accuracy of 95.5% in differentiating benign from malignant liver lesions. CONCLUSION: Triphasic CT Scan is a good non-invasive tool in characterizing and differentiating benign from malignant liver lesions