Hi Shanthi,

There is no hard and fast guideline for detecting glaucoma. In fact cup-to-disc ratio (CDR) is also not foolproof. We ocassionally see optic cupping in normal individuals. That is something we call physiological cupping. If you are looking for modalities other than CDR, I would suggest to go for RNFL thickness. You may take IOP measurement also. You can do a visual field analysis which also will give you a fair estimate. I would suggest an OCTA if you have doubt. I would suggest to do CDR in combination with RNFL thickness measurement with IOP also.

Hope this is helpful

@ Muneeb Faiq

Thanks for your valuable suggestions sir. I have an idea about RFNL measurement. But how the intraocular pressure can be measured/monitored automatically? Thought that it can be done only by clinical methods. If u give any clue of IOP that will be very helpful for my research.

Glaucoma and making a diagnosis . One cannot solely rely on a single investigation . With advances in medical technology . the diagnosis of glaucoma is now much more accurate to 40 years ago. From the baseline investigations such as history taking, slit lamp examination , corneal thickness asessment visual field assessment , we have now moved on to optical coherence tomography , optic disc assessment , nerve fibre examination , gonioscopy ,applanation tonometry , etc. Some patient cases need to be discussed at team meeting headed by experts in glaucoma in order to reach a corrcet diagnosis . In some eye centres where there is a glaucoma team, the patient care is of a much higher standard.

@ Ramesh seewoodhary

Thanks for highlighting the technology growth.

In glaucoma the optic disc may be sinking and NFs are being severed. Cupping is not taking place. If we would evaluate a glaucomatous disc in context of sinking disc/LC and severance of NFs and vasculature instead of cupping the diagnosis of disc for glaucoma will become as simple as ABC ( gestalt switch) . Glaucomaparadigmshift.com

Dear Syed Hasnain,

Thanks for your valuable input and for the reference link. I will refer and get back to you if further doubt arises.

One cannot rely solely on cup disc ratio as some racial groups do have large cup disc ratio which is regarded as normal . Other tests must be carried out , such as applanation tonometry , visual fields tests, OCT, etc.

Physiological cups are nothing more than the remnants of the Bergmeister’s papilla which supplies nutrition to the lens in the fetal life (Wolff anatomy). In the histology of the optic disc, this remnant tissue is identified as a central connective tissue meniscus of Kuhnt lying superficially on the surface of NFs layer. This is what we see with our ophthalmoscope. Some discs don’t have it and some have this meniscus as large as covering the 90% of the NFs area which we call as 0.9 cup/disc ratio. They are wrongly implicated in glaucoma. This fibrous tissue is not enlarging in glaucoma but disintegrating due to severance of NFs.

Another big fallacy: that the entire nerve fibers are concentrated in the so called neuroretinal rim whereas the central cupped area is a empty hole devoid of NFs; analogous to a doughnut. It is totally wrong: the so called neuroretinal rim is the exposed part of the NFs layer uncovered by this vestigial meniscus. NFs are also present underneath this remnant tissue as well.

If someone does not agrees: please see the histology of the normal discs, I can assure, you wouldn’t find a single histology of optic disc having a doughnut shaped configuration. I don’t know who gave us this wrong conception which we are blindly following every generation. If anyone can show us even a single histology confirming the doughnut shaped configuration of NFs, I will be extremely grateful.

Measuring the peripapillary RNFL thickness by OCT.

Measuring GCC complex parameters.

Measuring rim area and Disc damage likelihood scale DDL

And watching for rim notching and overhanging central retinal vessels

Watch Visual field defects from ,Humphrey visual fields on both eyes to suspect,detect and to evaluate the progression of glaucoma

You can monitor the Retinal Nerve Fiber Layer thickness with OCT, even monitor the functional visual loss with pattern full field ERG. The visual field defects from Humphrey ideally 30-2 would be great to track the record of glaucoma progression. I hope this will help.