Objective To investigate the metabolic changes in the visual cortex due to visual stimulation using high field functional proton magnetic resonance spectroscopy at 7.0 T.A clear picture of brain metabolism and neurotransmitter activity during activation was expected to be established.Methods Nine healthy subjects participated in this study. All MR measurements were acquired using a 7.0 T MR system and a 16-channel SENSE head coil. An initial fMRI scan was performed prior to spectroscopic acquisition in order to determine the activated region in the visual cortex.A cubic ROI of 2 cm× 2 cm × 2 cm was positioned inside the activated region for functional MRS acquisition.A short TE STEAM sequence was used for acquiring the MRS data. The functional paradigm comprised 6.6 min baseline followed by 13.2 min of visual stimulation and 19.8 min recovery.Summed averaged spectra for visual stimulus off and visual stimulus on were analyzed separately using LC Model and internal reference of water. A Wilcoxon signed rank test was conducted to compare the metabolite changes. ResultsDuring stimulation,concentration in Asp [ ( 3.20 ± 0.28 ) μmol/g ],Gln [ ( 2.07 ± 0.10 ) μmol/g ] and Gly [ ( 1.65 ± 0.11 )μmol/g ] was found to be significantly decreased,compared with that of ( 3.52 ± 0.28 ),( 2.25 ± 0.10 ) and ( 1.85 ± 0.11 ) μmol/g in rest ( Z =- 2.073,- 2.073 and - 2.429,respectively,P ＜ 0.05 ).The level in Glu [ ( 11.50 ± 0.11 ) μmol/g],GSH[ (2.45 ± 0.10) μmol/g] and Lac[ (0.89 ± 0.05) μ.mol/g]due to neuronal activation was found to be significantly increased,versus resting concentration of ( 11.28 ± 0.11 ),( 2.28 ± 0.10 ) and (0.79 ± 0.05 ) μmol/g,respectively ( Z =2.521,2.310,2.016,respectively,P ＜0.05).Glc level [ (1.54 ± 0.23 )μmol/g] exhibited a tendency to decrease throughout the period of stimulation,compared with that of [ (1.78 ± 0.28 ) μmol/g ] in rest,but the decrease did not reach statistical significance (Z =- 1.897,P ＞ 0.05 ).ConclusionsUsing a novel visual stimulation paradigm and 1 H MRS at 7.0 T and LC Model,the metabolic response to activation have been able to be observed.The observed changes of Asp,Glc and Lac concentrations in response to visual stimulation suggests that sustained neuronal activation raises oxidative metabolism to a new steady state.The observation of increased Glu with decreased Gln during stimulation can be interpreted as a stimulus driven increase in excitatory neurotransmitter cycling.The elevated GSH in the visual cortex in response to visual stimulation is a new observation.Possible explanations for this include detoxification of reactive oxygen species.

OBJECTIVE: Myelography has been shown to highlight foraminal and lateral recess stenosis more readily than computed tomography (CT) or magnetic resonance imaging (MRI). It also has the advantage of providing dynamic assessment of stenosis in the loaded spine. The advent of weight-bearing MRI may go some way towards improving assessment of the loaded spine and is less invasive, however availability remains limited. This study evaluates the potential role of myelography and its impact upon surgical decision making. METHODS: Of 270 patients undergoing myelography during 2006–2009, a period representing peak utilisation of this imaging modality in our unit, we identified 21 patients with degenerative scoliosis who fulfilled our inclusion criteria. An operative plan was formulated by our senior author based initially on interpretation of an MRI scan. Subsequent myelogram and CT myelogram investigations were scrutinised, with any additional abnormalities noted and whether these impacted upon the operative plan. RESULTS: From our 21 patients, 18 (85.7%) had myelographic findings not identified on MRI. Of note, in 4 patients, supine CT myelography yielded additional information when compared to supine MRI in the same patients. The management of 7 patients (33%) changed as a result of myelographic investigation. There were no complications of myelography of the total 270 analysed. CONCLUSION: MRI scan alone understates the degree of central and lateral recess stenosis. In addition to the additional stenosis displayed by dynamic myelography in the loaded spine, we have also shown that static myelography and CT myelography are also invaluable tools with regards to surgical planning in these patients.
Congenital Abnormalities ; Constriction, Pathologic ; Decision Making ; Humans ; Magnetic Resonance Imaging ; Myelography* ; Scoliosis* ; Spine ; Weight-Bearing

Background: /Aim: Endoscopic retrograde cholangiopancreatography (ERCP) training requires varying degrees of staff assistance regarding operation of the fluoroscopy machine via a foot pedal. Efficiency is important to acquire during this training due to radiation risks. In this study, we evaluate the effect of controlling endoscopy and fluoroscopy unit on duct cannulation rates (CRs) and total fluoroscopy time (FT) for fellows in training. Methods: 204 patients undergoing ERCP were randomized to one of two groups: 1) “Endoscopist Driven” group in which the endoscopist controlled the foot pedal for fluoroscopy, and 2) “Assistant Driven” group in which attending or fellow controlled the foot pedal while the other team member controlled the endoscope. Various measures including selective duct CR and total FT were recorded. Results: There was no significant difference in mean procedure duration between the two groups (32 minutes vs. 33 minutes, p=0.70). There was also no statistically significant difference in CR (83.7% vs. 77.4%, p=0.25) or FT (3.27 minutes vs. 3.54 minutes, p=0.48). Conclusions ERCP is a technically challenging procedure which requires extensive supervision. This study demonstrates that CR and FT are not affected by who controls the fluoroscopy.

Rodents are well-known reservoirs and vectors of many emerging and re-emerging infectious diseases, but little is known about their role in zoonotic disease transmission in Bhutan. In this study, a cross-sectional investigation of zoonotic disease pathogens in rodents was performed in Chukha district, Bhutan, where a high incidence of scrub typhus and cases of acute undifferentiated febrile illness had been reported in people during the preceding 4–6 months. Twelve rodents were trapped alive using wire-mesh traps. Following euthanasia, liver and kidney tissues were removed and tested using PCR for Orientia tsutsugamushi and other bacterial and rickettsial pathogens causing bartonellosis, borreliosis, human monocytic ehrlichiosis, human granulocytic anaplasmosis, leptospirosis, and rickettsiosis. A phylogenetic analysis was performed on all rodent species captured and pathogens detected. Four out of the 12 rodents (33.3%) tested positive by PCR for zoonotic pathogens. Anaplasma phagocytophilum, Bartonella grahamii, and B. queenslandensis were identified for the first time in Bhutan. Leptospira interrogans was also detected for the first time from rodents in Bhutan. The findings demonstrate the presence of these zoonotic pathogens in rodents in Bhutan, which may pose a risk of disease transmission to humans.
Anaplasma ; Anaplasma phagocytophilum ; Anaplasmosis ; Animals ; Bartonella ; Bartonella Infections ; Bhutan ; Communicable Diseases, Emerging ; Ehrlichiosis ; Euthanasia ; Humans ; Incidence ; Kidney ; Leptospira ; Leptospira interrogans ; Leptospirosis ; Liver ; Orientia tsutsugamushi ; Polymerase Chain Reaction ; Rodentia ; Scrub Typhus ; Zoonoses