Inflammation of the retina, usually caused by cytomegalovirus as a complication of human immunodeficiency virus disease.
A vascular disorder of the retina that leads to diminished vision as a complication of diabetes mellitus.
- Retina is composed of multiple microscopic layers
- Two innermost layers, the sensory retina and the retinal pigment epithelium (RPE), are the most relevant to common retinal disorders.
- The rods and cones, the photoreceptor cells- in the sensory layer of the retina.
- Beneath the sensory layer - RPE, the pigmented layer.
- When the rods and cones are stimulated by light, an electrical impulse is generated, and the image is transmitted to the brain.
Retinal detachment : Refers to the separation of the sensory retina from the choroid, a membrane dense with blood vessels that is located the retina and the sclera. When the retina is detached, it is deprived of its blood supply and source of nourishment and -losses its ability to function. This can impair vision to the point of blindness.
Etiology & risk factors
- Retinal break or tear or holes
- Predisposing factors include
- Increasing age
- Cataract extraction
- Glaucoma surgery
- Degeneration of the retina
- Eye Trauma
- Severe myopia
- Previous retinal detachment in the other eye
- Family history of retinal detachment
- Abnormal adhesions between the retina & vitreous body secondary to Diabetic retinopathy
- Other ocular disorders
The 4 types of retinal detachment are:
- A combination of rhegmatogenous and traction
- Most common form
- A hole or tear develops in the sesnsory retina , allowing some of theliquid vitreous to seep through the sensory retina and detach it from th RPE.
- High myopia
- Aphakia after cataract surgery
- Proliferative retinopathy
- Diabetic neovascularization related retinopathy (5-10%)
Tractional retinl detachment:
- Tension or a pulling force is responsible for the traction retinal detachment
- Generally patients with this condition have developed fibrous scar tissue from conditions such as diabetic retinopathy,vitreous haemorrhage,or the retinopathy of prematurity
- The haemorrhage and fibrous proliferation associated with these conditions exert a pulling force on the delicate retina .
Exudative retinal detachments
- Are the result of the production of serous fluid under the retina from the choroid .
- Conditions suc as uveitis and macular degeneration may cause the production of this serous fluid
Shrinking of the vitreous humor due to aging or pulls on the retina due to to etiological factors
Atrophic retinal breaks (holes)
When the traction force exceeds the strength of the retina , it gets torn (retinal tear)
Liquid vitreous can enter the sub retinal space between the sensory layer & the retinal pigment epithelium layer
Rhegmatogenous retinal detachment
Abnormal membranes which mechanically pull on the retina
Detachment occurs with conditions that alow gluid to accumulate in the sub retinal space (eg: choroidal tumors, intraocular inflammation)
Secondary or exudative detachment
- Shade or curtain coming across the vision
- Cowebs (dust), hairnet or ring in the field of vision
- Bright flashing light (photopsia)
- The sudden onset of a great number of floaters.
- Patients do not complain of pain
- Visual field loss occurs in the opposite quadrant of the actual detachment
- Tear in the temporal region- creates visual defect in the nasal area Giant retinal tears involving entire retina- temporary blindness
- Peripheral tears- may not interfere with central vision
- History & physical examination
- Visual acuity measurement
- Ophthalmoscopy - areas of detachment appear bluish grey as opposed to the normal red-pink color
- Slit lamp microscopy
- Amsler grid test- An Amsler grid, as seen by a person with normal vision
There is no medical treatment for a detached retina
- Mydriatic agents
- Cycloplegic agents
- Photocoagulation of retinal break that has not progressed to detachment
Goal: To place the retina back in contact with the choroid and to seal the accompanying holes and breaks.
- This technique seal retinal breaks by creating an inflammatory reaction that causes a chorioretinal adhesion or scar
- It involves an intense, precisely focused light beam (argon lase) to create an inflammatory reaction
- This produces a Scar that seals the edges of the whole or tear, and prevents fluid from collecting in the subretinal space and causing a detachment. Cryopexy
- Uses extreme cold/nitrous oxide to freeze the tissue behind the retinal tear, stimulating scar tissue formation that will seal the edges of the tear.
- Extra ocular surgical procedure that involves indenting the globe so that the pigment epithelium, choroid and sclera move towards the detached retina
- This not only helps to seal retinal breaks, but also helps to relieve inward traction on the retina
- Surgeon sutures a silicone implant against the sclera, causing the sclera to buckle inward
- Pneumatic retinopexy
- Intravitreal injection of a gas to form a temporary bubble in the vitreous that closes retinal breaks and provides apposition of the separated retinal layers
- Surgical removal of the vitreous used to relieve the traction on the retina
- Used special when the traction results from proliferative diabetic retinopathy. It may be combined with scleral buckling.
Post operative care
- Bed rest
- Topical antibiotic
- Topical corticosteroid/ anti-inflammatory
- Special Positioning (must lie face down or on their side for days )& activity
- Use of proper protective eyewear to help avoid retinal detachments related to trauma Discharge planning and teaching
- Increased IOP
- Development of other retinal detachments
- Development of cataracts
- Loss of turgor of the eye
Proliferative vitreoretinopathy- Membranes develop in the vitreous cavity and on the retinal surface, exerting traction that causes folds in the retina.
- For the most part, nursing interventions consist of educating the patient and providing supportive care.
- PROMOTING COMFORT
- If gas tamponade is used to flatten the retina, the patient may have to be specially positioned to make the gas bubble float into the best position.
- Patients and family members should be made aware of these special needs beforehand, so that the patient can be made as comfortable as possible.
- TEACHING ABOUT COMPLICATIONS
- Follow-up examination and close monitoring
- Must be taught the signs and symptoms of complications, particularly of increasing IOP and postoperative infection.