==TOLUENE AND OPTIC ATROPHY== MEDLINE Rinsho Shinkeigaku 1992 Apr;32(4):421-425 [A case of chronic toluene intoxication with atrophy of cerebrum, cerebellum and brainstem on CT and MRI]. [Article in Japanese] Fujita K, Koga Y, Takemasa K, Koike H, Akai J Department of Neuropsychiatry, School of Medicine, Kyorin University. A 28-year-old man developed neurological disorders consisting of cerebellar symptoms and dementia over a period of 8 years of inhalation of toluene. He also developed bilateral optic atrophy. CT scan and MRI revealed atrophy of cerebrum, cerebellum and brainstem. The severity of neurological symptoms corresponded with the findings of CT and MRI. Furthermore, MRI (T2) showed reduced signal intensity in bilateral thalamus. This patient was also admitted to another hospital 2.5 years ago. Compared with the previous findings, present examinations showed significant progress of the atrophy of cerebrum and brainstem. It was suggested from the results of ABR that the disturbance of the brainstem was aggravated through this period. ---------- Acta Neurol Scand 1985 Nov;72(5):512-517 Nervous system effects of long-term occupational exposure to toluene. Juntunen J, Matikainen E, Antti-Poika M, Suoranta H, Valle M Forty-three male rotogravure printers with long-term toluene exposure and 31 age- and sex-matched offset printers without toluene exposure were examined in detail. Clinical, neurophysiological, neuropsychological and neuroradiological examinations and assessment of autonomic functions did not reveal any statistically significant differences between the groups. The results suggest that occupational long-term exposure to toluene under these circumstances does not have clinically significant adverse effects on the nervous system. Exposure to toluene seemed to be associated with heavy drinking. ---------- Arq Neuropsiquiatr 1994 Mar;52(1):90-92 Cerebellar atrophy related to chronic exposure to toluene. Case report. Damasceno BP, de Capitani EM Faculdade de Ciencias Medicas (FCM), Universidade Estadual de Campinas (UNICAMP), SP, Brasil. A 31-year-old woman presented slowly progressing ataxia and neurasthenic symptoms after 14-year occupational exposure to low concentration toluene vapour. Examination disclosed only cerebellar signs. Cognitive functions were normal except moderate visuo-spatial and constructive deficit. CT imaging showed severe pancerebellar atrophy without pathological signs in other brain structures. Two years after she was removed from workplace, CT imaging and ataxia showed no worsening, while visuo-constructive function improved. The authors warn against possible neurotoxic risk associated with this kind of exposure. ---------- Hum Toxicol 1989 Jul;8(4):293-300 Chronic neurological toxicity associated with exposure to volatile substances. Lolin Y Department of Chemical Pathology, National Hospitals for Nervous Diseases, London, UK. 1. The main neurological disorders associated with chronic VSA are peripheral neuropathy, cerebellar disease, chronic encephalopathy and dementia. Apart from peripheral neuropathy, the clinical features are non-specific, evidence for solvent-related toxicity is in most cases circumstantial and there is no clear dose/response relationship. 2. Peripheral neuropathy is mainly associated with n-hexane and methyl n-butyl ketone. 3. Cerebellar disease is usually associated with toluene exposure; in the more severe cases there is often radiological evidence of irreversible cerebellar atrophy. 4. Chronic encephalopathy and dementia are the most serious consequence of solvent exposure, particularly to toluene in abusers and to mixed solvents in industrial workers. Postmortem studies in some abusers have shown generalized axonal degeneration, demyelination and brain atrophy. 5. Further studies on low level solvent exposure are needed as little is known about the neurological consequences of mild VSA, especially as regards individual susceptibility and possible interactions between solvents and other toxins such as ethanol. ---------- Ann Neurol 1988 Jun;23(6):611-614 Toluene abuse causes diffuse central nervous system white matter changes. Rosenberg NL, Kleinschmidt-DeMasters BK, Davis KA, Dreisbach JN, Hormes JT, Filley CM Department of Neurology, University of Colorado Health Sciences Center, Denver. We describe the findings of magnetic resonance imaging (MRI) of the brain in 6 chronic toluene vapor abusers and the neuropathological findings in 1 abuser not studied by MRI. MRI in 6 chronic toluene abusers revealed the following abnormalities: (1) diffuse cerebral, cerebellar, and brainstem atrophy; (2) loss of differentiation between the gray and white matter throughout the central nervous system; and (3) increased periventricular white matter signal intensity on T2-weighted images. Another chronic toluene abuser (MRI not performed) died as a result of acute toluene overdose. The brain displayed diffuse, ill-defined myelin pallor, maximal in cerebellar, periventricular, and deep cerebral white matter. Neurons were preserved throughout, axonal swelling or beading was not seen, gliosis was minimal, and occasional, scant perivascular macrophage collections were seen. Taken in concert, these findings suggest that the pathological and MRI abnormalities are due to either increased water content of the white matter or subtle toluene-induced metabolic changes in myelin. ---------- Neurology 1986 May;36(5):698-702 Neurologic sequelae of chronic solvent vapor abuse. Hormes JT, Filley CM, Rosenberg NL Neurologic abnormalities were seen in 13 of 20 patients with a history of chronic solvent vapor (primarily toluene) abuse for 2 or more years. The patients were evaluated after an abstinence period of at least 4 weeks, to avoid neurologic effects of acute intoxication. Neurologic signs included cognitive (60%), pyramidal (50%), cerebellar (45%), and brainstem/cranial nerve (25%) findings. Eight of nine CTs revealed diffuse atrophy of cerebral hemispheres, cerebellum, and brainstem. BAERs were abnormal in three of four patients, and EEG abnormalities were seen in three of seven patients. Chronic exposure to solvent vapor may cause persistent neurologic impairment. ---------- Neurology 1983 Oct;33(10):1337-1340 Multifocal central nervous system damage caused by toluene abuse. Lazar RB, Ho SU, Melen O, Daghestani AN Four toluene abusers had evidence of severe multifocal central nervous system damage. Impairment of cognitive, cerebellar, brainstem, auditory, and pyramidal tract function, as well as CT evidence of cerebral cortical, cerebellar, and brainstem atrophy, have been noted. In addition, we found opsoclonus, ocular flutter, and ocular dysmetria. All three patients tested had abnormal brainstem auditory evoked potentials, indicative of brainstem dysfunction. The patient with opsoclonus had CT evidence of brainstem, cerebellar, and cerebral cortical atrophy. ---------- J Adolesc Health Care 1982 Aug;3(1):37-39 Solvent abuse associated cortical atrophy. Schikler KN, Seitz K, Rice JF, Strader T Eleven of 42 toluene inhalers were evaluated with computed tomography scans because of neurologic abnormalities. Six of the 11 were found to have cerebral cortical atrophy. In addition, two of the six had cerebellar atrophy. All six had been exposed to toluene for at least 10 years. This study suggests that atrophy of the central nervous system may occur in chronic toluene abusers. ---------- Int Arch Occup Environ Health 1980;46(3):219-231 Neurological picture of organic solvent poisoning in industry. A retrospective clinical study of 37 patients. Juntunen J, Hupli V, Hernberg S, Luisto M A retrospective evaluation of neurological, neuroradiological, neurophysiological, psychological, and laboratory findings on 37 patients, remitted to the Institute of Occupational Health, Helsinki because of suspected poisoning due to organic solvents, was performed. Patient selection was made on the basis of performed pneumoencephalography (PEG). Most of the patients had been exposed to a mixture of solvents (19 cases). Carbon disulphide exposure had occurred in six cases, trichloroethylene in five cases, and the rest of the patients had been exposed to styrene (one case), thinner (two cases), toluene (1 case), methanol (1 case), and carbon tetrachloride (two cases). Clinical neurological findings comprised slight psycho-organic alteration, cerebellar dysfunction, and peripheral neuropathy. The PEG showed changes suggesting brain atrophy in 63% of the patients. Slight asymmetric central atrophy and localized cortical atrophy were the most frequent findings. The main electroencephalographic finding was slight diffuse slow-wave. Electroneuromyography showed slight changes suggesting peripheral neuropathy in 23 of the 28 patients examined. Psychological alterations were seen in all patients: personality changes and psychomotor disturbances were the most common findings. Because individual constitutional differences existed, no clear-cut exposure-effect relationship could be established. Thus, neurological evaluation of all those exposed to neurotoxic agents who present symptoms, regardless of the degree of current exposure, is important.