[Sensory ataxia in peripheral neuropathies--etiological and pathological analysis of four cases]

Among 85 neuropathy patients admitted and studied in the Department of Neurology, University of Occupational and Environmental Health, Japan, from 1979 to 1990, four patients suffering from sensory ataxia are reported with special reference to their etiological and pathological conditions. All of them were classified as having immune-mediated neuropathy. The first patient, a 56-year-old woman, was diagnosed as having chronic progressive ataxic sensory neuropathy. Her symptoms became progressively worse over a nine-year period after onset, but no evidence of cancer has been revealed. The positive rheumatoid factor was the only other feature noted. The second patient, a 63-year-old woman, after extensive laboratory studies, including the biopsy of the lymph node at the bifurcation of the bronchus in search of the cancer, was diagnosed as having subacute sensory neuropathy with small cell carcinoma of the lung. Chemotherapy was completed without subsequent obvious clinical benefits. The clinical diagnosis was confirmed on autopsy 29 months after the onset. The symptoms of the first patient were indistinguishable from those of the second patient, especially in the early clinical stage. In both patients, the proprioceptive sensations were severely affected and the disturbance of the proprioceptive sensations seemed to be almost parallel with the ataxia signs. The main site of the lesion seemed to be the neuron in the dorsal root ganglion in the first patient, as well as in the second patient who showed a marked loss of neurons in the dorsal root ganglion considered to be the primary lesion on autopsy.(ABSTRACT TRUNCATED AT 250 WORDS)

Asbestos fiber analysis in 27 malignant mesothelioma cases

The asbestos body counts per 5 gm wet lung tissue in 27 (23 pleural and 4 peritoneal) malignant mesothelioma cases derived from 19 autopsy and 8 surgical cases were, according to our own criteria, low level exposure in 13 cases (48.2%), moderate level exposure in 2 cases (7.4%), and high level exposure in 12 cases (44.4%). In our previous study on 235 consecutive autopsy cases, the low level exposure was considered to be environmental, the moderate level was secondary or blue collar, and the high level was occupational. In the present study, about half of the cases examined (44.4%, high level exposure) are closely related to some occupational asbestos exposure and the other half (48.2%) to environmental exposure. The type and size of asbestos fibers from the 12 cases of high level exposure were analyzed and the characteristics were compared with those of cases of low level exposure without lung cancer or mesothelioma. Most fibers analyzed (98%) were longer than 5 microns and thicker than 0.10 micron by our counting rules. In the control group, predominant fibers were tremolite or actinolite. In all the 11 pleural mesothelioma cases, the content of amosite fibers was significantly higher than in the controls. In one case of peritoneal mesothelioma, incipient asbestosis was found and the predominant fibers were crocidolite. It is suggested that the presence of amosite and crocidolite is linked to mesothelioma. The mean lengths of amosite and crocidolite, as detected by our resolution capabilities, were 36.0 and 20.9 microns, and the mean diameters were 0.51 and 0.27 micron, respectively. Both amosite and crocidolite fibers had high aspect ratios (94.2 and 115.4).

[A case of follicular bronchiolitis with broncho-pleural fistula in rheumatoid arthritis]

A 67-year-old male diagnosed clinically as having rheumatoid pleuritis and bronchiolitis was treated with adrenocorticosteroid. His clinical findings improved, but following the tapering of the steroid dose, exacerbation occurred. After the steroid dose was increased, serological findings improved, but chest X-ray findings revealed no improvement. To re-evaluate the etiology of the bronchiolar lesion, open lung biopsy was performed. The biopsy specimen showed lymphocytic infiltration and formation of lymphoid follicles in and around the bronchioles. The pulmonary lesion was diagnosed as follicular bronchiolitis.

[A case of adult T cell leukemia/lymphoma with motor and sensory polyneuropathy]

A 62-year-old man was admitted to our hospital because of two months continuing paresthesia and muscle weakness of distal portions of the four limbs. On general physical examination, skin lesions, lymphadenopathy and hepatosplenomegaly were not found. Neurological examination revealed moderate weakness in the bilateral distal muscles of the lower limbs and left distal muscles of the upper limbs, and slight weakness in the right distal muscles of the upper limbs and the bilateral proximal muscles of the four limbs. Hand grasping powers were 24 kg and 2 kg on the right and left, respectively. The biceps, triceps and radial reflexes were decreased on the right, but normal on the left. The Achilles tendon reflex was decreased on the right and absent on the left. Paresthesia and superficial sensory disturbance were observed with glove and stocking distribution, which was more severe on the left side. The vibration and position senses were slightly decreased in the distal part of the lower limbs. On the laboratory examinations, serum anti-HTLV-I antibody was positive and no abnormal lymphocytes were observed in peripheral blood. Cerebrospinal fluid findings were normal, and anti-HTLV-I antibody was negative. Motor and sensory conduction velocities were normal or slightly decreased in all of the limb nerves examined, but the amplitudes of the compound muscle action potentials and the sensory nerve action potentials were asymmetrically decreased. Needle EMG showed fibrillation potentials and giant spikes with a reduction in number of motor unit potentials. The histological examination of the biopsied sural nerve revealed severe axonal degeneration without evidence of vasculitis or infiltration of abnormal lymphocytes.(ABSTRACT TRUNCATED AT 250 WORDS)

Motor potentials evoked by magnetic stimulation of the motor cortex in normal subjects and patients with motor disorders

Motor evoked potentials (MEPs) elicited by magnetic coil stimulation of motor cortex were studied at rest and during maximum voluntary muscle contraction in 20 normal subjects and 42 patients with motor disorders. MEP parameters employed in this study included: onset latency, amplitude, MEP/M wave amplitude ratio and background EMG/MEP area ratio. Maximum voluntary contraction increased the amplitude of MEPs compared to the size of M waves elicited by peripheral nerve stimulation. A reduced MEP/M wave amplitude ratio had a higher correlation with pyramidal tract involvement than did a prolonged MEP onset latency. Analysis of MEP parameters may help in the differential diagnosis of cerebral infarction, ALS and cervical spondylotic radiculomyelopathy. The inhibitory period which follows MEPs during voluntary contraction was observed in all subjects; the mean duration in normal subjects was 126.6 +/- 29.5 msec. The mean duration of the inhibitory period in patients with cerebral infarction, ALS and cervical spondylotic radiculomyelopathy was 73.9 +/- 41.7 msec, 79.5 +/- 54.5 msec and 85.1 +/- 36.5 msec, respectively. These values were significantly shorter than in normal subjects.

[Drug induced blood dyscrasis in the Kanto district]

Ten years experience of 14 hospitals in Kanto district with drug induced blood dyscrasia (DBD) were reviewed. There were 78 patients, male/female ratio was 1:1, and cases more than 80 years old were 10.3%. It was very difficult to identify the causative agents, and only 8 cases were definitive. After disease 9 case were died, and DBD prolonged more than 50 days from onset in 8 patients. Thirty-one patients (39.7%) were due to Antibiotics, beta-lactam were most frequent, 12 cases were due to analgesics, 5 patients were due to thiamazole. In order to elucidate the incidence of DBD, studies had carried out concerning antibiotics and H2 receptor antagonists (H2RA). DBD due to antibiotics increased from 0.5% in 1981 to 4.2% in 1982, because medication of third-generation cephalosporins was began to use. In 109 outpatients with H2RA, there was no DBD, but in 54 hospitalized patients DBD were found in 3.6%. DBD might be more frequent in fact. It is necessary to start big study and to develop new technique for confirmation.

Biochemical abnormalities in developing E1 mouse

Complex biochemical abnormalities were found in the early developmental stage of the E1 mouse. First, the E1 mouse has abnormal levels of specific amino acid concentration within a week from birth. Second, an unusual expression of poly(A)+ RNA from the one-day newborn liver of the E1 mouse was detected by use of Cot 100 DNA as a probe. Third, sodium channels are increased in synaptosomes and at the mRNA expression level of the 3 or 4-week-old E1 mouse brains, compared with the ddY mouse. These results suggest that the biochemical abnormalities described in this study may affect greatly the epileptogenesis of E1 mouse.

[Morphometric analysis of normal human sural nerves for systematic clinical application]

To obtain normative data on the sural nerve for clinical evaluation of the pathologic process and severity of the various peripheral nerve disorders, a morphometric analysis was made on 30 control sural nerves from normal volunteers, and from patients and cadavers with no evidence of peripheral nerve involvement. The ages of volunteers, patients and cadavers ranged from 13 to 83 years. The data obtained included 1) the mean frequency of abnormal teased myelinated fibers and its upper limit value of 95% confidence interval, and 2) the mean densities of total, large and small myelinated fibers and of unmyelinated fibers and their lower limit value of 95% confidence interval for each decade. The linear correlation between the age and each of the frequencies of abnormal teased myelinated fibers and the densities of total, large and small myelinated fibers and of unmyelinated fibers were statistically significant (P less than 0.01). Therefore, the morphometric data obtained from the disease nerve should be compared with the normative data adjusted for the age of the subject described in this study.

Cortical somatosensory potentials evoked by magnetic stimulation: effect of body height, age, and stimulus intensity

Cortical somatosensory evoked potentials elicited by non-invasive magnetic stimulation at Th10, Th12, and L5 vertebral levels and at mid-gluteus and ankle were studied in 45 normal controls varying in body height and age. Peak latencies of P2 evoked by ankle, mid-gluteus and L5 stimulation were correlated with body height. However, P2 latencies evoked by Th10 and Th12 stimulation were independent of body height. In contrast, all N2 latencies evoked by Th10, Th12, L5, mid-gluteus and ankle were correlated with body height. There were no correlations between latencies of P3 and N3 and body height. No peak latencies of cortical components were affected by age within the age group studied (15-67 years). In the intensity study, N2 showed double peaks when low to moderate stimulus intensities were applied to Th12 vertebra. Furthermore, in 2 patients with mild somatosensory dysfunction of lumbar roots or cord, N2 evoked by L5 stimulation revealed double peaks with prolonged interpeak latencies between the first peak of N2 and P3, which might be related to the temporal dispersion of the afferent fibers. These data suggest that the N2 component is induced by both fast and slow afferent fibers.

[Clinical study on heterogeneity of chronic myelomonocytic leukemia]

We examined fourteen patients with chronic myelomonocytic leukemia (CMMoL) according to the following staging criteria at diagnosis; Group A: bone marrow (BM) blast less than 5% (eight cases), Group B; BM blast more than 5% and less than 30% (five cases), Group C; BM blast more than 30% (one case). Compared with Group A, Group B patients have much more peripheral blood leukocyte, granulocyte and monocyte counts, LDH level, and serum and urine lysozyme levels. Two of the five Group B cases transformed to acute leukemia (BC) within one and a half year, and other three patients died of infection and hemorrhage within a year. On the contrary, three of the eight Group A patients survived four years, and transformation to acute leukemia occurred in only one case after four years. Autopsy revealed multiple organ infiltration of monocytoid granulocytes on the patients with advanced stage and more bone marrow blasts. Two cases have coexistence of myeloproliferative disorders, one with essential thrombocythemia, and another with myelofibrosis, which, later, transformed to acute leukemia. And a Group C patient transformed to chronic phase with chemotherapy, and maintained the state for six years, but at the end stage, mature monocytes increased and pancytopenia developed. These findings indicate the heterogeneity of CMMoL in respect of the disease stage and the coexistence of other myeloproliferative disorders.

Serial somatosensory evoked potentials in a patient with familial hypobetalipoproteinemia, and vitamin E deficiency

Serial somatosensory evoked potentials (SEPs) to median and posterior tibial nerve stimulation in a case with familial heterozygous hypobetalipoproteinemia and vitamin E deficiency were investigated over a period of 4 years. In serial SEPs to posterior tibial nerve stimulation, interpeak latencies between N20 and P2 were delayed even in the early clinical stage, although the peak latency of N20 was normal. N20 latency was delayed when the patient noted paresthesia of the lower extremities. Interpeak latencies between N20 and P2 were progressively prolonged, and finally both peaks disappeared. Progressive dysfunctions of spinal posterior columns and peripheral somatosensory pathways were discovered by serial SEP studies.

Simultaneous immunoenzymometric assay for antibodies against human interleukin-2 and human serum albumin in rat serum

A simultaneous immunoenzymometric assay for anti-human interleukin-2 antibody and anti-human serum albumin antibody in rat serum was developed. Two antigen-immobilized polystyrene balls were immersed in a diluted serum sample in an assay tube and then the antibodies on the balls were made to react with a horseradish peroxidase labelled anti-rat IgG antibody in the same tube after washing. The enzyme activity of each ball was measured by fluorometry. Not only were the sensitivity (70 ng/ml each), assay recovery (100-101%), and precision (C.V. = 5-13%) comparable to those of conventional immunoenzymometric assays using one antigen-immobilized ball but the assay was also much more feasible for mass routine assays. Thus, conventional immunoassays can be replaced by this convenient simultaneous method.

1-Methyl-4-phenylpyridinium (MPP+) induces NADH-dependent superoxide formation and enhances NADH-dependent lipid peroxidation in bovine heart submitochondrial particles

We studied the effects of 1-methyl-4-phenylpyridinium (MPP+), a metabolite of a parkinsonism-inducing drug, on the superoxide formation and the lipid peroxidation in bovine heart submitochondrial particles. The NADH-supported formation of superoxide radicals was induced by MPP+ at the concentration which is considered to exist in mitochondria of dopamine neurons. The formation increased as the NADH-ubiquinone reductase activity was inhibited by MPP+. The NADH-supported lipid peroxidation by the particles in the presence of ADP-Fe3+ chelate was also enhanced by MPP+ at similar concentrations. The formation was inhibited by succinate and the reduction of endogenous ubiquinone seems to be related to the inhibition. A possibility was discussed that the formation of superoxide anions and the lipid peroxidation may contribute in the cytotoxicity of the drug.

[Effect of zirconium on immunological reactions of T cells and macrophages in mice]

The effects of zirconium (Zr) on T cells and macrophages in mice were studied in vitro using the indexes of immunological reactions, mitogenesis of C3H/HeJ mouse thymocytes induced by PHA and the production of interleukin-1 of C3H/He mouse intraperitoneal macrophages (MIL-1). The mitogenesis of thymocytes induced by PHA when stimulated with Zr solutions at various concentrations or culture supernatants of macrophages stimulated with LPS and Zr, or Zr alone, ware as shown below. 1. The mitogenesis of thymocytes by PHA was enhanced in the presence of Zr at 0.625-2.5 microM, and suppressed in the presence of Zr at 5-10 microM in culture 2. This reaction was enhanced by the addition of supernatants of macrophages stimulated with LPS and Zr. The most activation by LPS and Zr was shown at concentrations of 0.625-1.25 microM in culture, and the degree activated corresponding to 12.5-25 I.U. of MIL-1. 3. On the other hand, this reaction was inhibited by addition of supernatants of macrophages stimulated with Zr alone. From these results, it is suggested that Zr serves various functions such as an activator or inhibitor of T-cell mitogenesis by PHA, and that this may depend upon the Zr concentration in culture. In regard to the effect of Zr on MIL-1 production, Zr may activate this reaction by LPS, and Zr alone may induce MIL-1 production from macrophages.

[Fibronectin (FN) concentrations in plasma and cerebrospinal fluid (CSF) from guinea pigs with experimental allergic encephalomyelitis (EAE) induced by myelin basic proteins]

The aim of this study was to ascertain whether the FN concentrations in plasma and in CSF are related to the symptomatic status of EAE induced in guinea pigs by myelin basic protein. Guinea pigs were immunized with myelin basic proteins in Freund's complete adjuvant, and after the appearance of neurological symptoms, the plasmas and CSFs from these animals were individually collected. The FN concentrations in these specimens were determined by a solid-phase inhibitory radioimmunoassay using a rabbit antibody specific for guinea pig FN. In plasmas from EAE induced animals, the average value of FN concentrations was lower than that from control animals, but in CSFs from EAE induced animals the average value was slightly higher than that from control animals. The FN concentration in plasma from individual animals with or without EAE was not related to that in the respective CSF, and no direct correlation between the symptomatic severity of EAE and the FN concentration in CSF from the respective animals was observed. These results indicate that the FN concentrations in CSFs probably increase in association with the induction of EAE in guinea pigs, but the levels are highly variable in individual cases, and that the FN concentration in CSF is not available to use as a consistent indicator for EAE in guinea pigs.

[Vibratory and cooling detection thresholds in diabetes mellitus]

Vibratory and cooling detection thresholds (VDT and CDT) were determined at both the palmar aspect of the distal phalanx of the right index finger (upper limb) and the plantar aspect of the distal phalanx of the right great toe (lower limb) in 53 consecutive patients with diabetes mellitus (NIDDM), in order to analyze the frequency of the abnormality of each threshold and the relationship between each threshold and the clinical or laboratory findings. VDT in the lower limb was statistically correlated with age, duration of diabetes mellitus, and blood urea nitrogen value of each patient, but not with fasting blood glucose and hemoglobin A1C levels. VDT in the lower limb was significantly greater in the groups of patients with each of the subjective sensory disturbances, peripheral neuropathy (based on our criteria), retinopathy, and proteinuria. Forty-seven per cent of the patients showed clinically peripheral neuropathy, and the frequencies of the abnormality of VDT, CDT and VDT or CDT were 34, 26 and 45%, respectively. VDT and CDT reflect the abnormality of different populations of the peripheral nerve fibers and seem to be affected separately. The determination of both VDT and CDT is useful for the evaluation of the neuropathic state of diabetic patients.

[A case of hereditary motor and sensory neuropathy of neuronal type with retardation of motor development]

An atypical case of hereditary motor and sensory neuropathy of neuronal type with retardation of motor development was described. The patient was a 15-year-old boy who had suffered from distal muscle weakness with atrophy of four limbs and deformities of hands and feet since age 6 months. These symptoms were slowly progressive. He had never walked. His parents were not consanguinous. His parents and two siblings were unremarkable on neurological examination and on nerve conduction studies. On neurological examination, he showed severe degree of muscle weakness and atrophy in the distal upper and lower limbs, moderate degree of muscle weakness and atrophy in the proximal upper limbs and slight degree of made weakness and atrophy in the proximal upper limbs. Deep tendon reflexes in four limbs were decreased or absent. Vibration sensation was moderately decreased in the distal parts of four limbs. On the nerve conduction studies, no sensory nerve potential was recorded in the median, ulnar and sural nerves bilaterally. Motor nerve conduction velocity of the right tibial nerve was 21 m/sec and the amplitude of the compound muscle action potential (M-wave) was 0.15 mV, and no M-wave was elicited with the electrical stimulation of the median, ulnar and peroneal nerves. Neelde EMG showed fibrillation potentials and giant spikes with a reduction of the number of motor units. On sural nerve biopsy, the densities of both myelinated and unmyelinated fibers were severely decreased.(ABSTRACT TRUNCATED AT 250 WORDS)

Evoked potential studies in mitochondrial encephalomyopathy

Evoked potentials were studied in a patient with a mitochondrial encephalomyopathy revealing a defect of nicotinamideadenine dinucleotide dehydrogenase and cytochrome C oxidase in the mitochondria of a muscle biopsy specimen. The biopsy specimen showed myopathic changes with ragged-red fibers and markedly decreased cytochrome C oxidase in the muscle fibers. Subcortical somatosensory evoked potentials to median nerve stimulation were normal in the peak latencies of N9, N11, and N13. Cortical somatosensory evoked potentials to median nerve stimulation revealed significantly delayed peak latencies of N20, P20, P25, and N26, although N16 latency was normal. In particular, the interpeak latency between N16 and N20 was significantly delayed. In topographic maps, N20 and P20 were delayed in the peak latencies with normal scalp distributions. Dysfunction of somatosensory cortex indicated by the delay of cortical somatosensory evoked potentials may be related to a cortical mitochondrial abnormality. The absence of responses to auditory stimulation within 10 milliseconds could be related to the dysfunction of peripheral acoustic nerves.

Synthesis and antibacterial activity of novel 2-methyl-1-oxacephalosporins

New 2-methyl-1-oxacephem compounds having 2-(2-aminothiazol-4-yl)-2-(alkoxyimino)acetamido substituents at C-7 and various C-3 side chains were synthesized starting from (3R,4S)-phenyloxazolinoazetidinone (8). Introduction of the 2 beta-methyl group into the 1-oxacephem nucleus increased the stability to beta-lactamases. OCP-9-176 (7b) having the (1-methylpyridinium-4-yl)thiomethyl group at C-3 showed potent antibacterial activity and a broad spectrum.

[Myelodysplastic syndromes in the aged]

Seventy-five cases of myelodysplastic syndromes (MDS) in the aged (over 60 years) were analysed for hematological findings, immunological parameters and response to treatment in respect to prognostic significance. They were diagnosed according to the FAB classification, but patients with hypoplastic marrow were included if myelodysplasia was evident. Thirty-four percent of patients with primary acquired refractory anemia (PARA) or primary acquired sideroblastic anemia (PASA), and 36% of patients with RA with excess of blasts (RAEB) had hypoplastic bone marrow. The positive rates of antinuclear antibody in PARA or PASA, and of rheumatoid factor in PARA or PASA and in RAEB were higher than those in normal aged controls. Cellularity of bone marrow was inversely related to the length of survival. Among the patients with PARA or PASA, survival time was significantly longer in the group of hypoplastic bone marrow than in the group of hyper- or normo-plastic bone marrow, and in the group of good responder to treatment than in the group of poor responder and nontreated patients.

[Alpha 2-plasmin inhibitor plasmin complex in patients undergone surgery in femoral neck fracture]

The alpha 2-plasmin inhibitor-plasmin complex (alpha 2-PI-PM), alpha 2-plasmin inhibitor (alpha 2-PI) and some functions of coagulation and hemostasis were assayed on aged patients who were operated for femoral neck fracture. After the surgery, APTT, PT, fibrinogen, AT-III and platelet counts were in normal range or slightly deviated, which did not match with the DIC diagnostic standard. FDP levels in the operation group (337 +/- 303 ng/ml) were significantly increased compared to the level of the normal aged persons (64 +/- 9.9 ng/ml). The alpha 2-PI-PM in the operation group was 2.92 +/- 3.56 micrograms/ml, which was significantly higher than the alpha 2-PI-PM level (0.76 +/- 0.45 micrograms/ml) in the normal aged persons. Moreover, 3 in 7 operation cases, showed the increase of alpha 2-PI-PM levels over 5 micrograms/ml. The alpha 2-PI-PM in DIC group was 5.29 +/- 5.17 micrograms/ml. These data suggest that the patients are in the pre DIC state after surgery. In titers of FDP and alpha 2-PI, there were no differences between patients treated with and without heparin. alpha 2-PI-PM levels were improved in 5 out of 7 cases with the heparin treatment. On the other hand only one in 6 cases who did not receive heparin therapy showed the improvement of alpha 2-PI-PM level. In some cases without heparin treatment, the alpha 2-PI-PM level increased in the course of treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

A new aminothiazolylcephalosporin having 1-carboxyethoxyimino group, ME1228

Aminothiazolylacetamidocephalosporins having 1-carboxyethoxyimino groups were synthesized and found to have excellent antibacterial activities including anti-pseudomonal activity and low toxicities. Among these cephalosporins, ME1228 having (S)-1-carboxyethoxyimino substituent and being combined with an (N-ethyl-4-pyridinio)thiomethyl group at C-3 showed marked therapeutic effects against systemic infections in mice and was selected as the best candidate for further evaluation.

[Long survival of a patient presented with blastic crisis of chronic myelomonocytic leukemia]

A 77-year-old man was diagnosed as having acute myelomonocytic leukemia (M4) with increased ringed sideroblasts in the bone marrow (BM) in October, 1979. Complete remission was achieved and ringed sideroblasts disappeared after two courses of CMP (cytarabine, 6-mercaptopurine, prednisolone) therapy. Following remission, there was no increase of blasts during the course of the disease, but monocytosis and dysmyelopoiesis persisted for about seven years. The monocytosis was controlled by 6-mercaptopurine. In June, 1986, however, monocytosis in peripheral blood (PB) and BM developed again, and there was severe pancytopenia and reappearance of ringed sideroblasts without increase of blasts. The patient died of pneumonia on September, 1986. Postmortem examination revealed hypercellular marrow with a few blasts, leukemic cell infiltration into spleen, liver and lymph nodes, ad lung cancer. His clinical and hematological features after remission of acute leukemia accorded with those of CMMoL. The dysmyelopoiesis observed in this case in not induced by anti-leukemic agents, but originated from the same clone as the initial AMMoL, and his disease was thought to be CMMoL converted from blastic crisis to chronic phase.

[Optic neuropathy induced by thinner sniffing]

A case of optic neuropathy induced by thinner sniffing is reported. A 17-year-old girl, who had been sniffing a lacquer thinner for three months, suffered acute blindness followed by optic atrophy. Brain computed tomography revealed symmetrical low attenuation areas in the bilateral putamen. An analysis of the thinner by gas chromatography showed that its major components in a vaporized state were methyl alcohol and metyhl acetate. The optic neuropathy was induced by these solvents. In the diagnosis of the intoxication of mixed organic solvents, the measurement of each solvent in its vapor phase is considered to be quite important.