OBJECTIVES To develop a quantitative and noninvasive method of bone marrow cellularity evaluation in solvent-exposed painters. METHODS Six painters (mean age 46.5 years, 5 males and one female) with hypocellular marrow, and 132 controls were examined using magnetic resonance imaging (MRI). A full examination of the peripheral blood and a bone marrow biopsy was done on each patient. Signal intensities were measured at the vertebral bodies from T12 to S1 on both the T1- and the T2-weighted image (T1WI and T2WI). Signal indices were calculated by dividing the signal indices of the vertebral bodies by that of the paraspinal muscle and the subcutaneous fat in the same view. RESULTS The Bone marrow cellularities of the cases painters were between 20.3% and 33.6%. Signal indices based on the muscle at T1WI were greater in the cases of the painters compared to those of the controls (p<0.05, p<0.01). Signal indices based on the muscle at T1WI were significantly higher in older women compared with men (p< 0.05 ) . After adjusting for age and gender, the signal index of cases at S1 based on muscle of T1WI was higher than that of the controls by 0.364. Five of the six cases had a muscle signal index at S1 of T1WI higher than the mean + 1 standard deviation for the same age group and gender. CONCLUSIONS MR signal indices are influenced by constitutional factors such as fat content, bone density, and the presence of other pathology. However, after adequate adjustment, it can be used as a useful indicator of bone marrow cellularity in a high-risk population.
We experienced three cases of high signal intensity observed by Brain Magnetic Resonance Imaging in CO2 arc welders of steel-frame manufacturing industry. Case 1 was a 35 years old man who has been an CO2 arc welder for 10 years, admitted a sudden onset of tonic clonic seizure. He complained fever, chilling and myalgia since 3 days before admission. On admission, in the test of manganese exposure indices, manganese concentrations of blood, urine and scalp hair were 5.17 microgram/dL, 22.00 microgram/l and 31.25 ppm respectively. Case 2 was a 35 years old man who has been an CO2 arc welder for 20 years. On admission, He complained fatigue, numbness and weakness of extremities, and decrease of libido. In the test of manganese exposure indices, manganese concentrations of blood, urine and scalp hair were 6.34 microgram/dL, 14.62 microgram/l and 57.87 ppm respectively. In neurologic examination, Palmo-mentis reflex and Myerson sign were observed. Case 3 was a 33 years old man who has been an CO2 arc welder for 16 years. On admission, He complainer loss of appetite, numbness of extremities, fatigue and decrease of attention. In the test of manganese exposure indices, manganese concentrations of blood, urine and scalp hair were 5.14 microgram/dL, 13.79 microgram/l and 50.08 ppm respectively. In neurologic examination, Myerson sign was observed. In brain magnetic resonance imaging, T1WI showed symmetrical high signal intensity in basal ganglia and midbrain of three cases. Authors argued that they were developed by manganese exposure, and we considered that follow up study would be necessary.
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A Study on the Total, Particle Size-Selective Mass Concentration of Airborne Manganese, and Blood Manganese Concentration of Welders in a Shipbuilding Yard Jong Su Park, Pan Gyi Kim, Jee Yeon Jeong Journal of Korean Society of Occupational and Environmental Hygiene.2015; 25(4): 472. CrossRef
Occupational Diseases in Korea Seong-Kyu Kang, Eun A Kim Journal of Korean Medical Science.2010; 25(Suppl): S4. CrossRef
Occupational Neurological Disorders in Korea Eun-A Kim, Seong-Kyu Kang Journal of Korean Medical Science.2010; 25(Suppl): S26. CrossRef
This study was carried out to investigate the relationship between brain magnetic resonance imaging (MRI) and neurological findings in welders exposed to manganese fume. Thirty five welders from a bus manufacturing factory who were occupationally exposed to low dose manganese fume were examined. We collected the information on the demo graphic factors and welding careers. Laboratory investigations included blood and urine manganese concentration and blood chemistry. Brain MRI was checked, and high signal intensity of the globus pallidus was graded from 0 to 3 compared to the white matter of the frontal lobe. Neurologic examination wart carried out. The results were as follows ; 1. The mean age of workers was 48.3+/-5.7 years, mean duration of welding was 21.4 +/-5.6 Years. 2. On brain MRI, high signal intensity in the globes pallidus was observed in 27 workers (77.1%) Among them, 18 cases (66.7%) showed remarkably high signal intensity (grade 2) Mean concentration of blood manganese was higher in those with high signal intensity and correlated to the grade of high signal intensity (p=0.02) 3. On neurologic examination, no workers showed the finding of typical parkinsonism. But 11 workers (31.4%) showed subtle neurological abnormalities such as gait without associated arm movement, postural instability, intention tremor, and so on. Blood manganese concentration of neurologically abnormal group was 2.4+/-0.7 microgram/dL, which was significantly higher, compared to 1.8+/-0.7 microgram/dL of neurologically normal group (p=0.03). 4. Among 27 workers who showed high signal intensity on brain MRI, 10 workers (37%) were neurologically abnormal. Higher grade of signal intensity on globus pallidus showed higher rate of neurologic abnormality (p<0.05) Especially postural instability and gait without associated arm movement were prominent findings. These bindings suggest that high signal intensity on brain MRI might be associated with a prodromal sign of manganese intoxication. Careful neurologic examination should be tool lowed up on welders showing high signal intensity in the golbus pallidus of brain MRI.
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Parkinson's disease in a worker exposed to insecticides at a greenhouse Yangwoo Kim, Inah Kim, Jung-Min Sung, Jaechul Song Annals of Occupational and Environmental Medicine.2021;[Epub] CrossRef
Association of MRI T1 relaxation time with neuropsychological test performance in manganese- exposed welders R.M. Bowler, C-L. Yeh, S.W. Adams, E.J. Ward, R.E. Ma, S. Dharmadhikari, S.A. Snyder, S.E. Zauber, C.W. Wright, U. Dydak NeuroToxicology.2018; 64: 19. CrossRef
Occupational Neurological Disorders in Korea Eun-A Kim, Seong-Kyu Kang Journal of Korean Medical Science.2010; 25(Suppl): S26. CrossRef
State-of-the-Science Review: Does Manganese Exposure During Welding Pose a Neurological Risk? Annette B. Santamaria, Colleen A. Cushing, James M. Antonini, Brent L. Finley, Fionna S. Mowat Journal of Toxicology and Environmental Health, Part B.2007; 10(6): 417. CrossRef
Sequelae of fume exposure in confined space welding: A neurological and neuropsychological case series Rosemarie M. Bowler, Sanae Nakagawa, Marija Drezgic, Harry A. Roels, Robert M. Park, Emily Diamond, Donna Mergler, Maryse Bouchard, Russell P. Bowler, William Koller NeuroToxicology.2007; 28(2): 298. CrossRef
A purpose of present study is to provide basic information evaluating the utility of Magnetic Resonance imaging as a biological marker estimating manganese effects to central nervous system among welders, which is conducted by comparing urinary and blood manganese concentrations and signal intensities of brain MR images between exposed group and non-exposed group, evaluating the objectivity of subjective grading estimated by correlations between Pallidal signal intensity index (P. I) and subjective grades among exposed group, and comparing the difference of signal intensities according to presence of neurologic symptoms, signs and exposure variables among the exposed group. The exposed group is composed of 11 welders complaining severe symptoms or showing neurological signs, and the non-exposed group is composed of 5 patients who admitted a hospital. Urinary manganese concentrations and signal intensities in T1-weighted MR images among exposed group were higher than those of the non-exposed group significantly, which exhibits that increased signal intensities in T1-weighted MR image represent the effect of manganese exposure. P. Is among the exposed group revealed relatively high correlations with subjective grades ( gamma =0.63, p=0.037) , which suggests the objectivity of subjective grade. Signal intensity in globus pallidus was a suitable single variable representing the effect of manganese accumulation in C.N.S system appropriately, which was verified as follows ; Increased signal intensities among the exposed group had the highest frequency and intensity in the globus pallidus, and the P.I. had a relatively high correlation coefficient ( gamma 0.62, p=0.044) with total score of subjective grades. Signal intensity with subjective grading in globus pallidus represented very high correlation gamma =0.97, p=0.00) with total score of subjective grades, and had a similar correlation coefficient with many variables. It is hard to argue that signal intensities are markers representing pathologic change in C.N.S system or can be used as a diagnostic tool for manganese intoxication, because signal intensities had no difference between the exposed group and the non-exposed group according to presence of neurological signs.
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Occupational Neurological Disorders in Korea Eun-A Kim, Seong-Kyu Kang Journal of Korean Medical Science.2010; 25(Suppl): S26. CrossRef