DEFINITION
Glaucoma is a group of diseases that damages the eye’s optic nerve & can result in irreversible vision loss & blindness. The optic nerve supplies the visual information to the brain from the eyes. Glaucoma is usually, but not always, the result of abnormally high pressure (intraocular pressure, IOP) inside the eye.
TYPES OF GLAUCOMA
A fluid called “Aqueous Humor” is produced inside the eye which later exits the eye through an area known as the “Angle of Eye”. Glaucoma can be broadly classified into “Open – Angle” glaucoma & “Angle – Closure” glaucoma, depending upon the “openness” of this “Angle of Eye”.
RISK FACTORS
- Increased IOP : Most important factor
- Age : Glaucoma risk increases with age
- Race :
- Persons of African ancestry are at increased risk of Open Angle Glaucoma
- Persons of Asian race are at increased risk of Angle Closure Glaucoma
- Family History : A family history of glaucoma increases the risk
- High Myopia
- Ocular Injuries
- Corticosteroid Use
- Other Eye – Related Factors :
- Very Small Hyperopic Eyes
- Thin Corneas
- Diseases That Cause Poor Blood Circulation Affecting The Whole Body :
- Diabetes Mellitus
- Systemic Hypertension
- Systemic Hypotension
- Migraine
SYMPTOMS & SIGNS
- Patients with open – angle glaucoma do not notice any change in vision until the damage is quite advanced. There are typically no warning signs of open – angle glaucoma. This is why glaucoma is often called the “Silent Thief of Sight”.
- In patients with closed – angle glaucoma, the rise in eye pressure may occur suddenly (acute attack) or gradually or intermittently. Patients in whom eye pressure rises gradually usually give the same clinical picture as in open – angle glaucoma i.e. there are no warning signs. Patients with intermittent attacks may experience colored halos around light, headache or eye pain intermittently whenever eye pressure rises.
- Acute attack of closed – angle glaucoma is a medical emergency and characterized by :
- Severe unbearable pain in eye and forehead
- Nausea and vomiting
- Marked redness of eye
- Marked decreased vision or sudden loss of vision
- Colored halos around light
DIAGNOSIS
- Glaucoma can only be diagnosed by conducting a comprehensive eye examination which includes the following :
- IOP Measurement (Tonometry)
- Assessment of Angle of Eye (Gonioscopy)
- Central Corneal Thickness (CCT) Measurement
- Optic Nerve Head (ONH) Examination
- Visual Field Examination (Perimetry)
- Retinal Nerve Fiber Layer (RNFL) Examination
TREATMENT
- The damage caused by glaucoma is permanent and cannot be reversed. But timely and appropriate treatment can slow or stop the progression of the disease.
- It is important to counsel the patient and emphasize that the treatment for glaucoma is life – long and regular check – up is a must.
- Treatment of glaucoma is aimed at lowering the IOP.
- The various modalities for treatment of glaucoma are :
- Medication
- Laser
- Surgery
Glaucoma Services At MPEH
- Comprehensive Glaucoma Work – up
- Nd:YAG Laser Peripheral Iridotomy
- Green Laser Suturolysis
- Trabeculectomy with Mitomycin C
- Trabeculectomy with Ologen
- Glaucoma Drainage Implants
- Glaucoma Combined Surgery
- Pediatric Glaucoma Surgery
Investigative & Diagnostic Tools Available At MPEH
- Applanation Tonometry [GOLDMANN] & Non – Contact Tonometry [NCT] (TOPCON)
- Optical Pachymetry (TOPCON) & Ultrasonic Pachymetry (ALCON; BAUSCH & LOMB)
- 2 – Mirror & 4 – Mirror Gonioscopes (VOLK)
- Frequency Doubling Technology [FDT] (ZEISS)
- Humphrey Field Analyzer [HFA] (ZEISS)
- Anterior Segment OCT (Triton Plus OCT from TOPCON) : For Angle Evaluation
- Ultrasonic Biomicroscopy [UBM] (APPASAMY)
- + 90 D / + 78 D Stereoscopic Optic Nerve Examination (VOLK)
- Retinal Nerve Fiber Layer (RNFL) Evaluation (Triton Plus OCT from TOPCON) : Swept Source OCT
- Macular Ganglion Cell Complex (GCC) Evaluation (Triton Plus OCT from TOPCON) : Swept Source OCT
- Optic Disc Photography
- Optic Disc Angiography