Macular hole retinal tears retinal detachment vitrectomy electricity test physics

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A Macular Hole, as the name suggests, is a hole in the macula, which is essentially the center of the Retina. A hole usually results due to constant pulling or traction on the Retina by the shrinkage of the jelly-like substance known as the Vitreous Humor (described in Retina and Vitreous sub-section) that is present in front of the Retina. The causative factors for this kind of shrinkage of the Vitreous Humor range from Inflammatory Cystoid Macular Edema, Vascular Disorders of the Retina, Retinal Detachment to even changes on account of Advancing Age. Signs and symptoms include reduced sight and distorted or defective vision in the center of the eye.

The treatment for this condition is surgical and involves a Vitrectomy (removal of the Vitreous Humor from the eye), peeling of the Epiretinal Membrane (the membrane over the Retina that, in this condition, along with the Vitreous Humor pulls on the Retina itself) and the injection of a gas bubble to seal the hole and exert pressure on the Retina, thereby aiding in recovery.

A Retinal Tear is a break in the layers of the Retina. A tear may arise from conditions giving rise to excessive traction or pressure on the Retinal layers, such as: Trauma, High Myopia (Short-Sightedness), or certain inflammatory or infectious conditions of the eye. Alternatively, the Vitreous Humor may lose its jelly-like consistency and liquefy, thereby pulling on the Retina and causing a tear. This happens most often with advancing age. Many times, however, the cause is unknown or idiopathic. If the fluid in the eye seeps to the back of the Retina through this tear, it results in the separation of the Retina from the back of eye. This constitutes a Retinal Detachment. A detachment may on rare occasions occur following Cataract Surgery. Symptoms of a Retinal Tear or Detachment include Floaters, Flashes of Light, Diminished Vision and a "Dark Cloud" obstructing vision either peripherally or centrally.

A Retinal Tear is treated or sealed with Laser Therapy (akin to Spot Welding), so as to prevent its progress into a detachment or Pneumatic Retinopexy (done in-office), wherein a special gas bubble is injected into the eye to seal the tear. In the case of a detachment, however, the management involves further intervention. Treatment options vary and include Vitrectomy with Gas Bubble/Silicone Oil Insufflation (performed in an operating room), where the fluid separating the Retina from the inner eye wall is drained, and a gas or silicone oil bubble is placed inside the eye to seal the retinal defect. The silicone oil is removed from the eye at a later date i.e., after completion of the healing process, whereas the gas bubble disappears on its own after a period of time. At times, a device known as the Scleral Buckle ( a band placed in the eye to prevent future detachments) is used instead of the gas or the oil.

A surgical procedure carried out in the Operating Room (OR) wherein the jelly-like substance, the Vitreous Humor, is removed from the back of the eye. It serves as a treatment modality in conditions such as Retinal Detachment, Macular Hole, Vitreous Hemorrhage, Removal of a PC-IOL having suffered dislocation into the Vitreous Cavity. The Vitreous Cavity of the eye is entered through the creation of micro-ports in the Sclera (the white of the eye), followed by removal of the vitreous and the carrying out of any other repairs desired for the Retina, which may include either a membrane peeling (for Macular Holes) or Laser Ablation (for Retinal Tears and to stop bleeding through leaking blood vessels). The removed Vitreous is replaced by a chemically similar synthetic substance.

Vitrectomy Surgery, unlike laser, is an invasive surgery and therefore has potentially greater risks. The risks include: re-bleeding (10%), Retinal Detachment (2%), Cataract (almost certain in older patients) and infection (0.1%). Vitrectomy is done through three tiny openings. Recently we have advanced from approximately 1mm openings (20 gauge system) to 0.5 mm openings (25 gauge system). We feel this makes the surgery safer, faster and more comfortable. There are typically no sutures needed.