Accuracy of ultrasound vs. Fourier-domain optic biometry for measuring preoperative axial length in cases of rhegmatogenous retinal detachment

PURPOSE

To identify a method for accurately measuring preoperative axial length (AL) in cases of rhegmatogenous retinal detachment (RRD).

STUDY DESIGN

Retrospective study.

METHODS

This retrospective study included 83 eyes of 83 patients who underwent vitrectomy for RRD and had both preoperative and postoperative data for AL. Preoperative AL measurements for the affected eye were obtained using ultrasound (aUS-AL) and compared with those for affected and fellow eyes measured using optical biometry (aOB-AL and fOB-AL, respectively). Absolute differences between preoperative aUS-AL, aOB-AL, or fOB-AL measurements and postoperative AL (aPost-AL) were examined.

RESULTS

In the 41 eyes without macular detachment, the absolute difference between aOB-AL and aPost-AL (0.06±0.07 mm) was significantly smaller than between aUS-AL and aPost-AL (0.21±0.18 mm) and that between fOB-AL and aPost-AL (0.29±0.35 mm) (P = 0.017 and P < 0.001, respectively). In the 42 eyes with macular detachment, the absolute difference between aOB-AL and aPost-AL (1.22±2.40 mm) was significantly larger than between aUS-AL and aPost-AL (0.24±0.24 mm) and between fOB-AL and aPost-AL (0.35±0.49 mm) (P = 0.006, P = 0.016, respectively).

CONCLUSION

The current findings suggest that aOB-AL is more accurate than aUS-AL or fOB-AL in cases of RRD without macular detachment, while aUS-AL or fOB-AL is more accurate than aOB-AL in cases with macular detachment.

Analysis of temporal changes in thickness from conjunctiva to sclera after plication of the medial rectus muscle measured by anterior segment optical coherence tomography

PURPOSE

We evaluated long-term changes in conjunctival bulge after medial rectus muscle (MR) tightening using the plication method.

STUDY DESIGN

Retrospective and observational.

METHODS

Patients who underwent MR plication for exotropia from December 2016-March 2020 at Okayama University Hospital were included. Thirty two eyes of 27 patients were enrolled. The thickness from the conjunctiva to sclera (TCS) at the limbus and insertion sites were measured using anterior segment optical coherence tomography preoperatively and 1 month, 4 months, and 12 months postoperatively. Correlations between the 1- and 12 month postoperative TCS and amount of MR tightening were analyzed.

RESULTS

Preoperative and 4 month postoperative TCS at the limbus site were not significantly different (P=0.07). The 12 month postoperative TCS at the insertion site was significantly thinner than at 1 month postoperative (P<0.01), although significantly thicker than the preoperative TCS (P<0.01). No significant correlations were found between the amount of MR tightening (in mm) and 1- or 12 month postoperative TCS at the limbus (P=0.62 and P=0.98, respectively) and insertion (P=0.50 and P=0.24, respectively) sites.

CONCLUSION

The TCS at the insertion site peaked at 1 month postoperatively, continued to decrease for longer than 4 months postoperatively, continuing until 12 months postoperatively. The TCS at the insertion site 12 months postoperatively is thicker than preoperatively. The TCS at both the limbus and insertion sites was not related to the amount of medial rectus muscle tightening.

A nationwide survey of newly certified visually impaired individuals in Japan for the fiscal year 2019: impact of the revision of criteria for visual impairment certification

PURPOSE

To determine the status of visual impairment certification in Japan in the fiscal year 2019 and the impact of revising the criteria for visual impairment certification implemented in 2018.

STUDY DESIGN

Observational cross-sectional study.

METHODS

We requested welfare offices throughout Japan to submit data of age, sex, causative diseases, and visual impairment grades for newly certified visually impaired individuals aged ≥ 18 years during the fiscal year 2019. The certification was based on criteria of the Act on Welfare of Physically Disabled Persons.

RESULTS

Altogether, data were collected for 16,504 newly certified visually impaired individuals. The most common age group was 80-89 years (29.6%), followed by 70-79 (28.2%) and 60-69 (15.3%) years. The most common causative disease was glaucoma (40.7%), followed by retinitis pigmentosa (13.0%), diabetic retinopathy (10.2%), and macular degeneration (9.1%). The most common impairment grade was grade 2 (40.8%), followed by 5 (21.2%) and 1 (17.0%). Compared to the fiscal year 2015, there was a considerable increase in the number of individuals certified with glaucoma in the fiscal year 2019. Moreover, there was a significant increase in the number of individuals with certified grades 1 and 2 visual impairment, with a decrease in the number of individuals with certified grade 6 visual impairment.

CONCLUSION

The changes revealed in this study were primarily due to the revised certification criteria implemented in July 2018, indicating that it is important to review the certification criteria and to repeat surveys similar to the present study.