Epidemiology
The overall prevalence of secondary glaucoma across China between 1990 and 2015 was reported to be 0.15%, lower than the overall estimates for East Asia (0.39%). Varying forms of secondary glaucoma
Pigmentary glaucoma has lower incidence in Black and Asian populations, due to their characteristically thicker irises that result in a lower likelihood of pigment release, as compared to the White populations. Incidence of exfoliation syndrome-caused secondary glaucoma is estimated to be approximately 10% of the glaucoma patient population in the United States and over 20% of the patient population in Iceland and Finland.In populations above the age of 40, neovascular glaucoma has a prevalence of 0.4% worldwide. The incidence of pigmentary glaucoma decreases with age while in exfoliation syndrome the incidence increases with age. However, given the derived nature of secondary glaucoma, there may be no significant association between age, ethnicity or gender and the prevalence of the condition.Secondary glaucoma indicated after congenital cataract surgery is found between 6 and 24% of the cases noted, whereas, secondary glaucoma caused by primary IOL implantation was observed as 9.5%. Additionally, for patients with aphakia and secondary IOL implantation, 15.1% of the cases were determined. The incidence risk in primary IOL implantation in children with cataract in both eyes is lower than secondary IOL implantation and aphakic condition. However, this difference is not observed in the general population and populations with cataract in one eye.Due to lack of concrete and specific epidemiological evidence, further research is required to accurately estimate the prevalence of secondary glaucoma and its subtypes.
Yet, it is believed to be closely related to the onset of trabeculitis or vitreous toxicity.In paediatric congenital cataract patients under the age of two, cataract surgery is considered and frequently employed as the primary treatment. There are two types of therapeutic combination, primary and secondary lens implantation (IOL). In primary IOL, cataract surgery is performed alongside immediate implantation of IOL. However, in secondary IOL implantation, the patient is prescribed aphakic glasses or contact lenses till the implantation of IOL after a varied period of time between a few months or years. Primary IOL implantation is observed to significantly reduce and avoid the occurrence of secondary glaucoma in paediatric patients under the age of two. Herpetic anterior uveitis associated glaucoma
In patients diagnosed with herpetic anterior uveitis, elevated IOP and secondary glaucoma are often detected. This is due to two main reasons, the blockage of vitreous flow resulting from inflammation in the structures of the trabecular meshwork, and the sedimentation of inflamed cells. Specifically for viral anterior uveitis, patients with IOP levels above 30 mmHg are often suffer from secondary glaucoma caused by cytomegalovirus. Other forms of secondary glaucoma
Pigmentary glaucoma: In pigmentary glaucoma, the obstruction of the trabecular meshwork caused by iris pigment release results in increased IOP.