Staphylococcus Aureus is a Gram-positive cocci bacteria which had been found to be the causative organism in over 88% of patients with primary iliopsoas abscess. We report the case of a 53-year-old diabetic woman with end-stage renal failure diagnosed with left iliopsoas abscess with a catheter-related infection. Computed tomogram (CT) of abdomen and pelvis revealed hypodense lesions of left psoas, iliacus and quadratus lumborum suggestive of psoas abscesses. In addition, osteomyelitis changes at left sacroiliac and hip joint were seen. At surgery, she was found to have abscess at the posterior psoas muscle where she underwent open surgery drainage and percutaneous drain was inserted. A high index of suspicion of iliopsoas abscess should be maintained among haemodialysis patients presenting with intradialytic pelvic and hip pain and treated with optimal antibiotics therapy with appropriate surgical intervention.

Objective: This study investigates functional specialisation in, and effective connectivity between the precentral gyrus (PCG) and supplementary motor area (SMA) in seven right handed female subjects. Methods: Unimanual (UNIright and UNIleft) and bimanual (BIM) self-paced tapping of hand fingers were performed by the subjects to activate PCG and SMA. Brain activations and effective connectivity were analysed using statistical parametric mapping (SPM), dynamic causal modeling (DCM) and Bayesian model selection (BMS) and were reported based on group fixed (FFX) and random (RFX) effects analyses. Results: Group results showed that the observed brain activation for UNIright and UNIleft fulfill contralateral behavior of motor coordination with a larger activation area for UNIright. The activation for BIM occurs in both hemispheres with BIMright showing higher extent of activation as compared to BIMleft. Region of interest (ROI) analyses reveal that the number of activated voxel (NOV) and percentage of signal change (PSC) on average is higher in PCG than SMA for all tapping conditions. However, comparing between hemispheres for both UNI and BIM, higher PSC is observed in the right PCG and the left SMA. DCM and BMS results indicate that most subjects prefer PCG as the intrinsic input for UNIright and UNIleft. The input was later found to be bi-directionally connected to SMA for UNIright.The bi-directional model was then used for BIM in the left and right hemispheres. The model was in favour of six out of seven subjects. DCM results for BIM indicate the existance of interhemispheric connectivity between the right and left hemisphere PCG. Conclusion: The findings strongly support the existence of functional specialisation and integration i.e. effective connectivity in human brain during finger tapping and can be used as baselines in determining the probable motor coordination pathways and their connection strength in a population of subjects

Introduction: This multiple-subject fMRI study continue to further investigate brain activation within and effective connectivity between the significantly (p<0.001) activated primary motor area (M1), supplementary motor area (SMA) with the inclusion of BA44 during unimanual (UNIright and UNIleft) and bimanual (BIM) self-paced tapping of hand fingers. Methods: The activation extent (spatial and height) and effective connectivity were analysed using statistical parametric mapping (SPM), dynamic causal modeling (DCM) and the novel method of Bayesian model selection (BMS) for group studies. Results: Group results for UNIright and UNIleft showed contra-lateral and ipsi-lateral involvement of M1 and SMA. The results for BIM showed bilateral activation in M1, SMA and BA44. A larger activation area but with lower percentage of signal change (PSC) are observed in the left M1 due to the control on UNIright as compared to the right M1 due to the control on UNIleft. This is discussed as due to the influence of the tapping rate effects that is greater than what would be produced by the average effects of the dominant and sub-dominant hand. However, the higher PSC observed in the right M1 is due to a higher control demand used by the brain in coordinating the tapping of the sub-dominant hand fingers. Connectivity analysis indicated M1 as the intrinsic input for UNIright and UNIleft while for BIM, the inputs were both M1s. During unilateral finger tapping, the contra-lateral M1 acts as the input center which in turn triggers the propagation of signal unidirectionally to other regions of interest. The results obtained for BIM (BIMleft and BIMright) however yield a model with less number of significant connection. M1-M1 connection is unidirectional for UNIleft and UNIright originating from contra-lateral M1, and is inhibited during BIM. Conclusion: By taking into consideration the presence of outliers that could have arisen in any subject under study, BMS for group study has successfully chosen a model that has the best balance between accuracy (fit) and complexity.

Diffusion Tensor Imaging (DTI) is an advanced magnetic resonance imaging (MRI) technique. DTI provides quantitative information at microstuructural level via its parameter indices e.g. mean diffusivity (MD) and fractional anisotropy (FA). It also allows for visualization of neuron fibres through a specific technique called fibre tractography. Leukoaraiosis is an asymptomatic pathological condition of the brain white matter which appears hyperintense on T2-weighted MRI images. Association of leukoaraiosis with age and ischemic heart disease have been previously reported. The objective of this study is to compare MD and FA values measured in various areas of the brain white matter (WM), grey matter (GM), and cerebrospinal fluid (CSF) in humans using DTI. 30 subjects with leukoaraiosis and 12 subjects without leukoaraiosis underwent brain scan using GE 1.5 Tesla MRI system. Region of interests were located in the CSF and various WM and GM areas. Comparison of MD and FA values was made between leukoaraiosis tissue (LA) and normal appearing brain tissue (NABT) measured within the same leukoaraiosis subjects, and with normal brain tissue (CONTROL) of healthy control subjects. LA demonstrated a significantly higher MD and lower FA compared to NABT and CONTROL in frontal and occipital WM areas. No differences were observed in MD in any brain region between NABT and CONTROL. Whereas no differences were observed in FA between NABT and CONTROL except in the occipital WM. Fibre tractography showed 31.7% to 56.1% lesser fibre tracts in LA subjects compared to CONTROL subjects. Significant differences were found between pathological tissue compared to normal appearing brain tissue and normal brain tissue. Fibre tractography exposed reduced number of neural fibres in leukoaraiosis subjects as compared to normal subjects.
Diffusion Tensor Imaging

Sjörgren’s syndrome is an uncommon chronic autoimmune disorder that affects exocrine glands. Sialolithiasis is an obstructive salivary gland disease which is also uncommon in the parotid salivary gland. The existing literature has documented the occurrence of multiple calcifications within the parenchyma of the parotid glands in patients with Sjörgren’s syndrome. This report describes the first case of right parotid duct solitary sialolith formation in a 64 year old female patient with Sjörgren’s syndrome. Whether the salivary stone encountered in this case represents an oral manifestation of Sjörgren’s syndrome or is just a co-incidental finding was discussed.

The vast range of treatment protocols available for non-surgical management of chronic periodontitis can affect the consistency of clinical decision-making for dentists. This is further compounded by the different case definitions for periodontitis used in various clinical studies. The aim of this paper is to describe the steps taken leading to an expert consensus of periodontitis case definition followed by the development of a clinical pathway for managing chronic periodontitis. To assist reaching a consensus on a standard case definition of periodontitis for clinical research, a roundtable discussion was held involving 13 dental specialists and researchers from universities and the Ministry of Health. Participants discussed clinical experiences in identifying periodontitis and related issues based on scientific evidence. A further expert panel discussion consisting of 8 periodontists was conducted at another session to review current management practices and evidence-based practices available from the literature and generated a clinical pathway for non-surgical management of periodontitis. The case definition derived from the roundtable discussion recognises differentiation of selected clinical parameters and their thresholds as well as the extent and severity of the periodontitis. As for the newly developed clinical pathway, experts collectively defined the appropriate goals to satisfy the multidimensional needs of the patients which are translated into detailed elements of care, including the sequence of events of patients at each dental visit over time. The agreed case definition will facilitate selection and recruitment of cases for clinical studies while the clinical pathway can be used to reduce variations between clinicians.