The human eye is one of the most specialized organs of the body. Like in a camera, the eye too has powerful and specially designed optics - the Cornea & Crystalline lens. These focus the image onto the retina. The Cornea does most of the focusing. It has no blood circulation and breaths oxygen from the air. This wonderful living ’lens’ is optically clear and is the most sensitive part of our body.
Like in a camera, the eye too has powerful and specially designed optics - the Cornea & Crystalline lens. These focus the image onto the retina. The Cornea does most of the focusing. It has no blood circulation and breaths oxygen from the air. This wonderful living ’lens’ is optically clear and is the most sensitive part of our body.
The epithelium is layer of cells that cover the surface of the cornea. It is only about 5-6 cell layers thick and quickly regenerates when the cornea is injured. If the injury penetrates more deeply into the cornea, it may leave a scar. Scars leave opaque areas, causing the corneal to lose its clarity and luster.
Boman's membrane lies just beneath the epithelium. Because this layer is very tough and difficult to penetrate, it protects the cornea from injury.
The stroma is the thickest layer and lies just beneath Bowman's. It is composed of tiny collagen fibrils that run parallel to each other. This special formation of the collagen fibrils gives the cornea its clarity.
Descemet's membrane lies between the stroma and the endothelium. The endothelium is just underneath Descemet's and is only one cell layer thick. This layer pumps water from the cornea, keeping it clear. If damaged or disease, these cells will not regenerate.
Tiny vessels at the outermost edge of the cornea provide nourishment, along with the aqueous and tear film.
Corneal diseases can cause clouding and distortion of vision, and eventually blindness. There are many types of corneal diseases like infections due to contact lenses, dry eye, abrasions from trauma, and inflammations. Other conditions include keratoconus, pterygium etc.
Keratoconus is a frequently seen corneal disease, occurring in about 1 in 1000 people, which typically starts after the age of 10 yrs. The hundreds of filaments of collagen layers in normal cornea are linked to each other by cross linking, giving it an enormous strength. If these collagen cross-links are lost, as it happens in Keratoconus, there will be a progressive corneal thinning and stretching. This often occurs in both the eyes. The cornea bulges forward into an irregular cone shape. This causes distortion of the image, which cannot be corrected with glasses. The eye develops irregular astigmatism (cylindrical errors) and myopia [shortsightedness] and the vision would become blurred.
Risk factors include eye rubbing, family history of keratoconus, genetic predisposition, certain systemic disorders such as Down’s syndrome, ocular allergy, connective tissue disease etc. Diabetics won’t develop Keratoconus because of natural crosslinking from high glucose and UV light. Affects men and women in equal proportions and is bilateral in 90% of cases.
At early stages, the person feels the need for frequent change of spectacle correction. As the disease progresses, the vision deteriorates. Visual acuity becomes impaired at all distances, and night vision is sometimes quite poor. Keratoconus can cause substantial distortion of vision, with multiple images, streaking, sensitivity to light, eye strain from squinting in order to read, & itching in the eye.
This is usually done by an Ophthalmologist with a detailed eye examination including retinoscopy, keratometry, slit-lamp examination etc. Diagnosing early keratoconus can be tricky, since mild disease often does not show any signs on slit-lamp examination. Streak retinospcopy can pick up early Keratoconus.
At Karthik Netralaya a very sensitive instrument called the ‘Pentacam HR’ is used for early diagnosis. This is an automated instrument working on Shiemflug principal, and can pick up extremely early Keratocouns, that often starts in the back of the cornea.
Treatment of mild to moderate keratoconus is done temporarily by Contact lenses, which can be the regular RGP or specific and specialised, like Rose K lenses and mini scleral contact lenses depending upon the severity of the illness. The new modality of treatment is Corneal Collagen Crosslinking with Riboflavin (C3-R) stabilises the cornea from further deteriorating. In severe stages the person has to undergo corneal grafting surgery.
A new modality of treatment for mild to moderate keratoconus in which riboflavin eye drops are applied to the eye. The Riboflavin, when activated for approximately 15-30 minutes with UV-A light, strengthens the collagen cross-links within the stroma and so recovers some of the cornea's mechanical strength. CSL or C3R has been shown to slow or arrest the progression of keratoconus, and in some cases even reverse it to an extent.
This method works by increasing collagen cross-linking, which are the natural "anchors" within the cornea. These anchors are responsible for preventing the cornea from bulging out and becoming steep and irregular, which is the cause for keratoconus. Corneal collagen cross-linking (CXL) is established as an effective surgical treatment to increase the biomechanical stability of the cornea. We use CXL to treat idiopathic Keratoectasia such as keratoconus and pellucid marginal degeneration and post-LASIK ectasia etc.
The introduction of collagen cross linking (C3R, CXL, CCR, CCL and KXL) therapy promises to arrest the progression of conreal illensses. . The indications for CXL seem to be expanding dramatically, beyond conventionals. CXL is now being used preventively along with LASIK (called LASIK plus) and ASA (advanced surface ablations) in those who have risks of developing keratectasia as shown on Pentacam HR analysis. Conventional CXL machines cannot be used for these advanced treatments, and our new INTACS XL will be of enormous use in these special indications.
It is a UVA collagen cross linking instrument designed with special focus on usage, effective performance and safety. It is a versatile UV irradiating device for performing a corneal cross-linking procedure at a wavelength at 365mn, designed with illumination intensity in the range of 3.0Mw/Cm to 30.Mw/Cm at a working distance of 50mm. While conventional machines take 30 minutes to deliver the UV dosage, this new machine delivers it in 3 minutes. This means quicker treatment, and better cooperation by the patient during the treatment.
Intacs XL Corneal cross linking
The eye depends on the flow of tears to provide constant moisture and lubrication to maintain vision and comfort. Tears are a combination of water, for moisture; oils, for lubrication; mucus, for even spreading; and antibodies and special proteins, for resistance to infection. These components are secreted by special glands located around the eye. When there is an imbalance in this tear system, a person may experience dry eyes.
• Light sensitivity
• A gritty sensation
• A feeling of a foreign body or sand in the eye
• Blurring of vision
In addition to an imbalance in the tear-flow system of the eye, dry eyes can be caused by situations that dry out the tear film. This can be due to dry air from air conditioning, heat, or other environmental conditions.
This is a state-of-the-art technology for the comprehensive assessment of CVS, dry eye & tear film analysis and documentation. “Oculus Keratograph 5” offers several advanced diagnostic features in addition to its most reliable corneal surface topographic analysis. It incorporates a wide range of dry eye evaluation programs. Various parameters can be analysed quickly and non invasively.
- Non invasive TBUT
- Tear meniscus height
- Meibomian gland analysis
- Tear lipid analysis
- Tear film dynamics study
This new equipment revolutionises the diagnosis and management of dry eye & CVS especially in early stages. This is in addition to its diagnosing capabilities of corneal surface parameters in Keratoconus, pre LASIK & pre Cataract evaluations for premium IOL.
Oculus Keratograph 5
Corneal Transplantation or Grafting is a fine micro surgery where a defective Cornea is replaced by a healthy donated Cornea. The Cornea of a departed donor is gifted by a humanitarian family and is collected & processed by an eye bank. Cornea grafting is a highly skilled day care surgery. In spite of enormous research, there is no synthetic equivalent to God given precious Cornea.
Corneal transplantation is suggested when medicines fail to heal corneal diseases or when glasses or contact lenses cannot restore the vision due to corneal irregularities. Infections, Keratoconus, Injuries, scarring due to various reasons, corneal failure from previous surgeries, birth diseases etc. are some of the causes for corneal diseases.
Cornea donors can be of any age, sex or blood group. Corneas are only collected from donors after death. Common health issues like Diabetes, Hypertension, Thyroid imbalances, use of spectacles etc. do not affect the health of the donor cornea. Corneas from persons having corneal diseases, advanced cancer, communicable diseases like HIV, Rabies, Hepatitis, Viral brain infections etc., are not accepted.
• Penetrating Keratoplasty:
Here the entire thickness of the diseased Cornea is replaced by a healthy donor Cornea & is secured by multiple tiny sutures. It takes a few months to years for the patient to get back his potential vision.
• Deep Anterior Lamellar Keratoplasty: (DALK)
Here the defective outer part of the Cornea is replaced, leaving behind the healthy inner Descemet’s and endothelial layer. The risk of graft rejection is lesser in this procedure.
• Descemet Stripping Endothelial Keratoplasty: (DSEK)
Contrary to the previous surgery, only the unhealthy innermost layers of the Cornea are replaced with a thin layer donor Cornea, which includes some stroma Descemet’s and the healthy endothelium. This allows faster recovery of vision and better corneal integrity.
• Descemet Membrane Endothelial Keratoplasty (DMEK)
Here only the inner most ultra-thin single cell layered endothelium is transplanted along with its Descemet membrane. Your corneal surgeon will perform examinations like Slit lamp Biomicroscopy, Anterior segment OCT, Specular microscopy etc., and suggest the surgery best suited for you.
The department offers most recent advances in the field of corneal surgery which include:
(Optical, tectonic and therapeutic) with anterior segment reconstruction, Combined with SFIOL Vitreo-retinal procedures and Paediatric PK
Including Deep Anterior Lamellar Keratoplasty (DALK), Deep Lamellar Endothelial Keratoplasty (DLEK) and Descemet's Stripping EndoKeratoplasty (DSEK)
Offers the state of art facility for various laser refractive procedures like LASIK, Epi-LASIK, ASA, PRK and Wavefront guided customized ablation
• Advanced Intacs XL Corneal cross linking equipment
• Oculus dry eye lab & Oculus Keratograph 5
• Specular microscopy
• Oculus Pentacam HR
• Corneal topography Tomey IV Topographer
• Spectral domain Corneal OCT
• Computerized Contact Lens module for Keratoconus contact lens fitting Low visual aids to enhance vision in those with uncorrectable vision
• Deep lamellar & endothelial (DALK & DSAEK) cornea penetrating keratoplasty
• ‘Automated Corneal Shaper’ (ACS) for lamellar corneal grafting surgeries
• Specialized Contact lens fitting – for irregular cornea, keratoconus and for therapeutic purposes
Institute of Ophthalmology Private Limited
89, 7th cross, N R Colony, Near Bull temple,
Bengaluru - 560050. India
Monday to Saturday: 10:00 AM - 7:00 PM; Sundays Holiday
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