POAG: Enigmatic group of heterogenous diseases?

Reviewed by Louis R. Pasquale, MD

Different forms of glaucoma have unique features, and lumping them together represents a disservice to patients along with a missed opportunity for physicians to learn about the various glaucoma subtypes, said Louis R. Pasquale, MD.

New drug targets for primary open-angle glaucoma (POAG) that are precision-medicine based are needed and will be developed by studying various candidate mechanisms for the disease, explained Dr. Pasquale, director, Glaucoma Service, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston.

He provided an overview of a few subtypes of POAG he believes exist-i.e., paracentral OAG, African-derived OAG, and glaucoma associated with estrogen deficiency-to determine their differences and facilitate their diagnosis and management.

He described the case of a patient who presented with an apoplectic inferior altitudinal visual field loss in the left eye. However, IOP was relatively normal. The referring physician inquired if the patient had sustained a sudden ischemia or retinal embolic event, had newly discovered normal-tension glaucoma, or non-arteritic ischemic optic neuropathy.

This case illustrates the quandary in which ophthalmologists find themselves.

“How long have we been confused about POAG?” Dr. Pasquale asked. “The answer is: A really long time."

“The term is a misnomer,” he added. “The definition in the dictionary is pale blue or grayish green. The Latin root means ‘waterfall,’ which probably referred to patients who were functionally blind from a mature cataract.”

It was not until the invention of the ophthalmoscope that patients with clear media also were found to have excavated totally cupped optic nerves, which explained the blindness, Dr. Pasquale noted.

However, confusion about the disease persisted, and the terminology used might have actually confounded the confusion about the etiology of POAG, he said.

Internal server error