Value of optical coherence tomography measurement of macular thickness and optic disc parameters for glaucoma screening in patients with high myopia

BACKGROUND The basic method of glaucoma diagnosis is visual field examination,however,in patients with high myopia,the diagnosis of glaucoma is difficult.AIM To explore the value of optical coherence tomography(OCT)for measuring optic disc parameters and macular thickness as a screening tool for glaucoma in patients with high myopia.METHODS Visual values(contrast sensitivity,color vision,and best-corrected visual acuity)in three groups,patients with high myopia in Group A,patients with high myopia and glaucoma in Group B,and patients with high myopia suspicious for glaucoma in Group C,were compared.Optic disc parameters,retinal nerve fiber layer(RNFL)thickness,and ganglion cell layer(GCC)thickness were measured using OCT technology and used to compare the peri-optic disc vascular density of the patients and generate receiver operator characteristic(ROC)test performance curves of the RNFL and GCC for high myopia and glaucoma.RESULTS Of a total of 98 patients admitted to our hospital from May 2018 to March 2022,totaling 196 eyes in the study,30 patients with 60 eyes were included in Group A,33 patients with 66 eyes were included in Group B,and 35 patients with 70 eyes were included in Group C.Data were processed for Groups A and B to analyze the efficacy of RNFL and GCC measures in distinguishing high myopia from high myopia with glaucoma.The area under the ROC curve was greater than 0.7,indicating an acceptable diagnostic value.CONCLUSION The value of OCT measurement of RNFL and GCC thickness in diagnosing glaucoma in patients with high myopia and suspected glaucoma is worthy of development for clinical use.

SEQUENTIAL INTRAOCULAR PRESSURE MEASUREMENTS IN SUSPECTED OPEN-ANGLE GLAUCOMA

Objective To evaluate the variations of intraocular pressure （lOP） in suspected open-angle glaucoma （OAG） patients. Methods The variations of lOP were measured in 216 eyes of suspected OAG patients at 4-hour intervals for 48 h. Based on the results of the serial lOP measurements, optic disc changed and visual field defected, the patients were diagnosed as primary OAG （ POAG ）, normal tension glaucoma （NTG）, ocular hypertension （ OHT） , or physiologic cup （PC）. Results After the serial lOP measurements, 16. 7% of the suspected OAG patients were diagnosed as POAG, 32. 4% as NTG, 24. 5% as OHT, and 26. 4% as PC. The highest percentages of the POAG group had peak lOP at 8 AM （19. 4% ） and their trough lOP at 10 PM （27. 8% ） ; the NTG group had peak lOP at 12 AM （18. 6% ） and their trough lOP at 12 PM （22. 9% ） ; the OHT group had peak lOP at 4 AM （22. 6% ） and their trough lOP at 10 PM （26. 4% ） ; and the PC group had peak lOP at 4 AM （ 21. 1% ） and their trough lOP at 12 PM （ 21. 1% ）. The percentages of peak lOP outside clinic （ 8 AM - 4 PM） in the POAG, NTG, OHT and PC groups were 55. 6%, 50. 0%, 58. 4% and 45. 7%, respectively. The mean magnitude of variance was 5. 1 - 6. 7 mmHg in those suspected OAG patients. There was a strong positive correlation in lOP between both eyes at each time point of measurement and the variation curves of the right and left eyes had parallel profiles in those suspected OAG patients. Conclusion Serial measurement of lOP is still needed, in order not to miss the peak and the trough lOP readings in suspected OAG patients, which helps in better management of glaucoma.