Masatoshi Furushima

Changes in Refraction Caused by Induction of Acute Hyperglycemia in Healthy Volunteers

PURPOSE To determine whether the myopic changes and ocular hypotension after a glucose load are caused by hyperglycemia. METHODS Oral glucose tolerance tests were conducted on seven healthy young subjects with normal vision. The changes in the hematologic parameters and the refractive system were measured periodically for 150 minutes after the glucose load. RESULTS After the glucose load, there was an increase in plasma glucose level and the level of plasma osmosis, ocular hypotension, a myopic change in refractive power, shallowing of the anterior chamber, and a thickening of the lens. The degree of the myopic change exceeded the power of the residual accommodation. Normalization of the plasma glucose level led to a normalization of the intraocular pressure and a reversal of the myopic changes. CONCLUSIONS These findings suggest that the myopic changes that accompanied hyperglycemia were caused by a thickening of the lens resulting from a decrease in the tension of the zonule fibers of Zinn, and were secondary to ocular hypotension. Hyperopia appeared to be caused by the reversal of the myopia after normalization of plasma glucose levels.

Frosted branch angiitis associated with streptococcal infection: optical coherence tomography as a follow-up tool.

7-year-old boy presented withdecreased vision and conjuncti-vitis in both eyes. He had a flu-likeepisode with fever about 2 weeks ear-lier, and the skin of both palms hadpeeled off. His visual acuity (VA) was0.15 OD and 0.1 OS. Slit-lamp exami-nation showed conjunctival and ciliaryinjection, cells in the anterior cham-ber, flare and fine keratic precipitatesbilaterally. Ophthalmoscopy revealeddiffuse, white perivascular sheathingof the arteries and veins, tortuous anddilatated veins, scattered retinal haem-orrhages and papilloedema in botheyes (Fig. 1A). Fluorescein angiogra-phy demonstrated extensive dye leak-age from almost all vessels (Fig. 1B)and both optic discs were hyperfluo-rescent in the late phase. Indocyaninegreen angiography (ICGA) showed amottled background pattern, stainingof the vessels especially in the poster-ior pole, and hypofluorescence of thediscs with blurred margins (Fig. 1C).Optical coherence tomography (OCTModel 2000; Carl Zeiss Meditec, Inc.,Dublin, CA, USA) showed a clear ser-ous detachment and oedema in themacula (Fig. 1D, E). Goldmann peri-metry showed an enlarged blind spot.The amplitudes of the a- and b-wavesand the oscillatory potentials of theelectroretinograms (ERGs) elicited bya bright flash were significantlyreduced (Fig. 1F).Systemic examinations disclosed noabnormal findings except for high titresof anti-streptolysin O (ASO, 1830·)and anti-streptokinase (ASK, 5120·).From these findings, the subject wasdiagnosed with frosted branch angiitis(FBA). He was treated with topical0.1% betamethasone and 1.0% atro-pine along with i.v. prednisolone(580 mg⁄day) for 3 days and subse-quently oral prednisolone for 15 days(total 165 mg). Three days later, theaqueous inflammation and the peri-vascular sheathing were markedlyreduced. Thereafter, OCT and oph-thalmoscopy of the macular areashowed a resolution of the oedemafollowed by the appearance of a star-shaped figure (Fig. 1G, H). The sub-ject’s ERGs were markedly improvedbut were still not normal (Fig. 1I).The serous detachment (Fig. 1J, K)and finally exudates disappeared.Despite the rapid improvement inthe appearance of the retina, thepatient’s VA improved much moreslowly and attained 1.0 only after3 months. Fundus angiography at thattime demonstrated the complete reso-lution of all abnormal findings.The increase in the number of casesdiagnosed as FBA raises questionsabout whether this disorder representsa distinct clinical syndrome or merelya clinical sign of eyes with inflamma-tory conditions. From their descrip-tions in the literature, cases diagnosedas FBA are characterized by bilat-eral, perivascular retinal blood vesselsheathing, retinal haemorrhages andoedema of different degrees, panuveitisand papilloedema (Walker et al. 2004).Our case had diffuse angiitis involvingthe vessels of the macular and periph-eral retina and the choroid. Anterioruveitis and papilloedema were alsopresent. The abnormal ICGA findingssuggested that the choroid was alsoaltered, which probably accounts forthe decreased a-waves on ERG. Thereduced b-waves indicated alterationsto the inner retina. Whether thesefindings are also found in other chori-oretinal inflammatory diseases is yet tobe determined. The prevalence of FBAis reported to be higher in Asians thanin White populations (Walker et al.2004).Despite the marked panophthalmicinflammation, the eye responded wellto steroids. Our subject’s VA recov-ered to normal levels, but some FBAsubjects suffer a permanent loss ofvision caused by macular scarring(Kleiner et al. 1988; Walker et al.2004).

On response dysfunction in multifocal posterior pigment epitheliopathy.

Purpose To determine the electroretinographic properties of one patient with multifocal posterior pigment epitheliopathy. Methods Rod and cone electroretinograms (ERGs) and photopic ERGs elicited by long-duration stimuli were studied in a patient with multifocal posterior pigment epitheliopathy. Results The amplitudes of both the rod and cone ERGs were significantly reduced. Photopic ERGs elicited by long-duration stimuli demonstrated that the b-wave (“on” response) was abolished but the d-wave (“off” response) was reduced by only amplitude. Conclusion The ERG findings in multifocal posterior pigment epitheliopathy indicate that there is dysfunction not only of the photoreceptors but also in the signal transmission specific for the “on” pathway.

Subretinal Hemorrhage Displacement: A New Surgical Technique without Iatrogenic Retinal Break or Evacuation Procedures

When subretinal hemorrhages (SHs) involve the fovea and persist for a long time, significant macular damage and permanent visual acuity loss are common complications [1]. Because untreated SHs have such a poor visual prognosis, techniques for the removal or displacement of the SH have been developed. The most noninvasive surgical technique is a pneumatic displacement of the SH with intravitreal air or gas injection and a postoperative prone position [2]. This technique is easily performed but does not displace all SHs. We describe this alternative technique, its clinical use and results.