Exophthalmometry: a comparative study of the Naugle and Hertel instruments.

Exophthalmometry is frequently used as a tool in the evaluation of proptosis. The purpose of this study was to compare the clinical usefulness of the newly developed Naugle superior and inferior orbital rim-based exophthalmometer with that of the Hertel exophthalmometer, as well as to obtain normal values and analysis of possible race and sex differences. In the first part of this study, we measured 135 patients in a double-blind study in order to evaluate the repeatability of serial measurements using each instrument. Comfort was also evaluated in this series of patients. In the second part, a single observer measured 205 patients in order to obtain information for a multifaceted analysis. In the first part of the study, we found the Hertel measurement to be more variable in terms of coefficients of variation. We further found the Hertel base measurements to vary more between observers than those of the Naugle instrument. In the second part, we found that the mean values of globe position were not statistically different (mean Naugle, 17.23; mean Hertel, 18.61; p = 0.909). A significant difference was noted between black and white patients when using the Naugle instrument. A difference between white and black women was noted with the Hertel instrument. The results of this analysis strongly suggest that the values obtained from the Naugle exophthalmometer are more repeatable in serial measurements compared with the Hertel values. However, single measurements of globe position from all patients were statistically similar. We conclude that the Naugle instrument is comparable in accuracy to the Hertel instrument for measuring ocular position, as well as being more comfortable for the patient. The Naugle instrument has the advantage of measuring hyperophthalmos and hypoophthalmos with a vertical gradient scale.

Radial and astigmatic keratotomy experience by residents and fellows at a teaching institution.

PURPOSE: To retrospectively study 30 cases of radial and astigmatic keratotomy performed by third-year ophthalmology residents and cornea fellows. SETTING: Tulane University Medical Center, New Orleans, Louisiana. METHODS: Patients were selected based on correction for stable myopia without or with astigmatism. Four or eight radial incisions were made using the Russian (uphill) method. The astigmatic cuts were straight transverse. RESULTS: Uncorrected visual acuity postoperatively was 20/40 or better in 28 eyes (93%). Two patients(visual acuity 20/50 and 20/70) were scheduled for secondary procedures but were lost to follow-up. Complications included three microperforations without sequelae. CONCLUSION: Radial and astigmatic keratotomy to correct myopia or myopia with astigmatism can be safe and effective in the hands of a beginning surgeon.

A superior and inferior orbital rim-based exophthalmometer (orbitometer).

In exophthalmometry when the lateral orbital rim is used as the instrument's fixation base, any alteration in the rim will render serial measurements inaccurate. The exophthalmometer we describe (technically, an "orbitometer") uses the superior and inferior orbital rim areas as a base of reference, making it particularly useful in lateral orbitotomy procedures. This instrument can be aligned at the midpupil horizontally and vertically with a vertical fixation bar. In addition, a vertical bar gradient scale allows measurement of hypoophthalmos and hyperophthalmos.