Which type of laser surgery is effective in reducing severe vision loss from proliferative diabetic retinopathy?

Panretinal photocoagulation is the appropriate choice for addressing severe vision loss due to proliferative diabetic retinopathy. This condition is characterized by the growth of abnormal blood vessels in the retina, which can lead to serious complications, including vision loss.

Panretinal photocoagulation involves the application of laser energy to the peripheral retina to create numerous tiny burns. This process helps to reduce the oxygen demand of the retina, thereby decreasing the stimulation of abnormal vessel growth. The treatment effectively reduces the risk of severe vision loss by preventing the complications associated with proliferative diabetic retinopathy, such as vitreous hemorrhage and retinal detachment.

Other laser treatment options, such as argon laser trabeculoplasty, are designed to treat conditions like glaucoma rather than diabetic retinopathy. Peripheral iridotomy is utilized primarily for treating narrow-angle glaucoma and does not address the complications of diabetic retinopathy. Intense pulsed light therapy is generally focused on skin-related issues and has no direct application in treating retinal conditions.

Thus, panretinal photocoagulation directly targets the underlying pathology of proliferative diabetic retinopathy, making it the most effective surgical option to reduce severe vision loss from this condition.