[Histopathological and clinical studies of acute necrotizing ulcerative gingivitis and evaluation of treatment]

We report the clinical data, light and electron microscopic findings, therapy and clinical course of three cases treated for acute necrotizing ulcerative gingivitis. The following results were obtained. 1. An ulcerous lesion was observed in the gingiva of all three cases, with case I also showing a depressed lesion in the ulcerous region. 2. In all three cases, the gingival sections displayed ulceration and showed fibrin deposition and neutrophil infiltration on the surface of the ulcerous region. Congested blood vessels and neutrophil infiltration also were observed in the connective tissue beneath the ulcerous region. 3. Many microorganisms, fibrin, cell debris, and enlarged intercellular spaces of the epithelium were seen on the surface on the ulcerous region. 4. Localized treatment, mainly plaque control, was found to be effective clinically and histopathologically.

[Three dimensional analysis (XY plane and time) of averaged electroretinograms for the evaluation of rhegmatogenous retinal detachment and related pathological conditions]

Retinal functional imaging in patients with rhegmatogenous retinal detachment and related pathological conditions was investigated by three dimensional analysis of ERG topography. The three dimensional analysis revealed that the area of maximal amplitude deviated to the skin area closest to the location of the retinal detachment (paradoxical localization). In temporal retinal detachment, for example, the maximal amplitude of the a- and b-waves deviated toward the temporal side on the surface topography. The depth of the retinal detachment was clearly indicated by differential ERG topography. Flicker ERG with a stimulus frequency of 30Hz was especially successful in showing the existence and location of macular detachment within the area surrounding the temporal vascular arcades. ERG topography also indicated the meridional extent of retinal detachment. When there was detachment in two quadrants (e.g., two inferior quadrants), deviation in the surface topography of a- and b-waves appeared in the same quadrants. When detachment expanded into three quadrants, deviation of the amplitude of a- and b-waves closely resembled the extent of the detachment. In addition, however, there was inverse a- and b-wave surface topography on the opposite skin area. When there were two quadrants of retinal detachment, there were two quadrants of inverse a-and b-waves. When there were three quadrants of retinal detachment, there was only one quadrant of inverse a- and b-waves. No inverse a- and b-waves were detected when there was only one quadrant of retinal detachment. In such cases, however, deviation in the surface topography covered three quadrants. These abnormalities were detected in 90.6% of all cases with the retinal detachment disappeared after the retina was reattached. While the buckling procedure and argon laser retinopexy had little effect on the topographical distribution, it was markedly distorted by cryoretinopexy. No remarkable changes in the topographical distribution of a- and b-waves were detected in pathological conditions related to rhegmatogenous retinal detachment. This new method for functional imaging of the retina should be valuable for objective clinical evaluation of retinal detachment.

Short latency visual evoked potentials in functional amblyopia shown using moving topography

The conduction from the eye to the visual cortex through the brainstem was investigated in 43 cases of functional amblyopia by means of moving topography of short latency visual evoked potential (SVEP). Anomaly of the SVEP such as a defect of the main component and remarkable reduction of amplitude was found in cases with severe amblyopia whose visual acuity was less than 0.5. The incidence of abnormal SVEP was recognized in 44% of anisometropic amblyopia (18 cases), 52% of strabismic amblyopia (15 cases), and 50% of deprivation amblyopia (10 cases). The results suggested a reduction of electric activity in the subcortical visual pathway including transmitting nuclei.

Electrophysiological and pathological studies on Creutzfeldt-Jakob disease with retinal involvement

In a case of Creutzfeldt-Jakob disease in a 59-year-old female, multifocal degeneration from the cerebral cortex through the visual pathway to the retina was detected clinically, electrophysiologically, and pathologically. Visual evoked cortical potentials (VECPs) showed a peculiar huge negative wave in the early stage but the amplitude reduced gradually. The a- and b-waves of the ERG were detectable in the final stage. Dynamic topography of VECPs revealed a delay of excitation in the visual cortex in the early stage, but a complete defect of the cortical potential and diminished reactivity of the brain stem were apparent in the later stage. Pathological findings were the spongy degeneration of the cerebral cortex, demyelination of the white matter and the optic pathway, and the degeneration of the nerve fiber layer and ganglion cell layer of the retina.

Average responses evoked by moving grating pattern in the upper, central and lower visual field

Detectable visual evoked potentials were obtained in man by stimulation in the peripheral visual field with a 0.4 cycle/deg vertical grating pattern of 5 degrees arc subtense which moved twice per second horizontally at 415 degrees/sec through an amplitude of 8 degrees arc. These moving grating stimuli were presented to 10 normal subjects, centered 15 degrees above, or centered around, or centered 15 degrees below a fixation mark. The mean latencies (+/- S.D.) of the positive component of the potential evoked by stimuli to the central and 15 degrees eccentricity lower visual field were 114 +/- 17 msec and 104 +/- 20 msec, respectively, while latencies for 15 degrees eccentricity upper visual field stimuli were significantly (p less than 0.001) later with 148 +/- 20 msec.

Studies on visual evoked cortical response by liquid crystal phase difference haploscope: amblyopia and/or strabismus

Visual evoked cortical potentials induced by alternate stimulation of checkerboard pattern with the use of liquid crystal phase difference haploscope were investigated. The synchronization ratio of brain response was determined both in the group of normal binocularity and in the group with binocularity defect. The synchronization ratio of the group of normal binocularity (N = 30) is 100% at 1 Hz x 2, 98.5% +/- 3.9% at 5 Hz x 2, and 83.7% +/- 15.8% at 10 Hz x 2. On the other hand, in the group with binocularity defect, strabismus without amblyopia shows a reduction of the ratio only at the frequency of 10 Hz x 2. Anisometropic amblyopia shows a significant reduction of the ratio at 10 Hz x 2 and strabismus with amblyopia shows a remarkable reduction at 5 Hz x 2 and 10 Hz x 2. As for strabismus with or without latent binocularity, the latter cases show a significant reduction of the synchronization ratio. The reduction of synchronization ratio of VECP seems to have some relationship to the binocularity.

[Bilateral direct injury of oculomotor nerves in craniocerebral trauma-report of a case (author's transl)]

A 46-year-old housewife was admitted to the Kawasaki Hospital soon after traffic accident. She was struck in the right forehead. She was very slightly drowsy but well oriented. Both eyeballs were extremely abducted without any motility. The pupils were bilaterally dilated and equal in size with no response to light. There was a pronounced blephaloptosis on both sides. Another neurological abnormality was a slight right facial weakness. On skull films, a linear fracture in the right temporobasal region was noted but the views of the orbits were normal. A lumbal tap showed a mild subarachnoidal hemorrhage. Three weeks after the trauma, pneumoencephalography showed no abnormal finding. Throughout convalescence, no special treatment was given beyond medication. She improved steadily. Three years after injury, re-examination disclosed that lateral gaze was almost full to either side but upward and downward movements of both eyeballs were limited. In our opinion, the most likely cause of the disability in this case was bilateral direct damage of the oculomotor nerves near the petroclinoid ligament (Grüber).