The Utility of Three-dimensional CT in Orbital Diseases

PURPOSE: Orbital computed tomography was useful for evaluation of orbital truama because it can visualize most soft tissues, foreign bodies and bone details. Advancements in computer software makes three diemensional CT available with more higher quality and reasonable cost. We studied the officency, merit and limitation of orbital three dimensional CT. METHODS: We evaluated the conventional orbital CT and three dimensional orbital CT of the patients visited department of ophthalmology and emergency room to orbital trauma or other orbital diseases. RESULTS: The three dimensional orbital CT was not superior to conventional orbital CT in evaluation of orbital soft tissue disease but useful for evaluation of orbital bony details. CONCLUSION: In cases of coexamination with conventional orbital CT, the three dimensional orbital CT was useful for diagnosis and surgical planning in orbital truamatized patient.

Vascular Risk Factors in Normal Tension Glaucoma

To evaluate the implication of vascular factor in normal tension glaucoma, authors performed color doppler imaging[CDI] for ophthalmic artery, central retinal artery and posterior ciliary artery in 21 eyes of 12 patients in normal tension glaucoma and 16 eyes of 11 patients in normal control group. We compared peak-systolic velocity[PSV], end-diastolic velocity[EDV], mean velocity[MV], resistance index[RI] and pulsatile index[PI] between the two groups. We evaluate the difference in parameters according to age, sex, systolic and diastolic blood pressure, past history of diabetes and hypertension, cup-disc ratio and visual field change. In normal tension glaucoma group, PSV, EDV and MV of ophthalmic artery and central retinal artery were significantly decreased and pulsatile index was significantly increased compared to those of normal group. Resistance index was also increased in normal tension glaucoma group, but statistically not significant. All parameters of posterior ciliary artery had no significant difference between the two groups. Age was related positively to pulsatile index and resistance index of central retianl artery and diastolic blood pressure was related positively to resistance index of ophthalmic artery. Cup-disc ratio was related negatively to PSV and EDV of ophthalmic artery. Above results imply that blood flow velocity decreased by increasing resistance factor in normal tension glaucoma, therefore local vascular factor might be related to the development of the normal tension glaucoma and affected by age, blood pressure and cup-disc ratio change.

The Utility of Hand Held Autorefractometer for Refraction in Children

We studied the utility of hand held autorefractometer on the cycloplegic refraction for poor coorperated children by analyzing the data taken from hand held autorefractometer(Retinomax) and Canon R-10 autorefractometer. Seventy patients(140 eyes) were studied. We divided them into two groups according to the age: Group I included patients less than 4 years, Group II over 4 years. There were no statistic significant differences in the spherical and cylindrical values regardless of age and cooperability in cases of less than 6 diopter but statistic significant difference in cases of high refractive errors (>6 diopter) or cylindrical axis values. In Conclusion, this study revealed that hand held autorefractometer was useful for checking refraction of the poor coorperated children and the spherical and cylindrical values of Retinomax have no differences from the values of R-10 in the cases of less than 6 diopter.

Effect of Ganciclovir on cytomegalovirus Retinitis of a Renal Transplant Patient without Maintenance Therapy

Cytomegalovirus retinitis (CMV), an opportunistic infection of a immunocompromised patient, is a necrotizing retinitis occurred in AIDS or the patient using immunosuppressants. A 31-years-old male taken immunosuppressants after renal transplantation, had white granular foci and perivascular sheathings in the uper temporal retina of both eyes. Serologic test demonstrated positive response to bith IgG and IgM antibody against CMV. Argon laser photocoagulation was done and ganciclovir was intravenously treated 300 mg every 12 hours for three weeks without maintenance therapy. Nine months after treatment, there was no recurrence of retinitis. This result suggests CMV retinitis of renal transplanted patient may not need the maintenance therapy of ganciclovir.