“It is very rewarding when a sick animal puts his or her entire trust in us. We do not share the same language but with our actions, we hope they understand we are doing them no harm.” Today we say THANK YOU to Thelma and Kerry May of Mount Pleasant Animal Medical Centre (Farrer)!
First week after Hershey’s cataract surgery, praise God! She is recovering really well. And beginning to be more active than usual. I love how she walks more confidently now.
Thank you everyone for your continuing prayers and support. Big thank you to Dr Heng Yee Ling of Mount Pleasant (Farrer) for her professional care post-op! We are truly blessed and grateful.
Dom and Hershey
Dandelion (formerly named Baileys) the Shih Tzu was bought from a petshop as a puppy. When she developed pneumonia and severe ulceration of her left cornea, her family wanted to give her up to a shelter.
The cornea is the outermost covering of the eye. Corneal ulcers are painful wounds to one or more layers of the cornea. They are often caused by abrasions or scratches. Read more about corneal ulcers here.
Other causes of corneal ulcers include:
- entropion (rolling in of eyelashes)
- ectopic cilia (abnormal eyelashes rubbing on cornea)
- keratoconjunctivitis sicca (dry eyes)
When deep ulcers cause scarring or perforation of the cornea, the eye may need to be surgically removed. The eye may also need to be removed due to other conditions like:
- uncontrolled painful glaucoma (increased pressure in the eye)
- severe trauma or injury (puncture or perforation of eyeball)
- cancer of the eye
The surgical removal of an eyeball is called enucleation.
Symptoms of corneal ulcers include:
- red or watery eyes
- eye discharge
- rubbing eyes with paws (which causes further trauma)
LOSING AN EYE OR TWO doesn’t seem to matter much to Dandelion, Mei Mei or Emma. Life goes on for them, happily, one day at a time!
Most blind dogs and cats learn to form a mental map of their environment. Help them adjust with the following tips:
- Keep your blind pets safe in smaller areas until they are more comfortable to explore.
- Remove extra furniture or potentially hazardous objects.
- Keep the layout of your house constant. Avoid moving furniture around.
- Leave food, water bowls and litter trays (for cats) at the same place.
- Water fountains may be helpful. Your pets can hear and locate the water source more easily.
- Use scent markers or tactile clues (floor mats) at certain areas.
- Before petting or picking up your blind pets, let them know you are approaching by calling their names or clapping your hands.
- Create a quiet and safe spot where your blind pets can retreat.
Cataract is the leading cause of blindness, especially in senior dogs. Once a cataract has developed, no eye drops or medication can reverse it. Thankfully, surgery can remove cataracts and help blind dogs see again.
what is a cataract?
The lens is a clear structure inside the eye that focuses light and images on the retina. It is made up of clear protein surrounded by a very thin and elastic capsule. A cataract is an opacity or cloudiness that forms within the lens.
Very small cataracts would not affect vision too much. However, as the cataract progresses, it can cause uveitis (inflammation in the eye), retina damage or glaucoma, leading to permanent blindness. Signs of uveitis include increased eye redness, squinting, excessive tearing and light sensitivity.
WHAT IS NOT A CATARACT?
Senile Nuclear Sclerosis is commonly seen in dogs 7 years and older. Lens fibers are continuously being produced. As older fibers are compressed in the nucleus, the lens take on a bluish-grey hue. No treatment is required as light can pass through a sclerotic lens. The cloudiness does not impair vision.
“We adopted Nala 6 months ago. Because of her cataracts, she knocks into things, especially white walls or chairs, and when she gets excited playing ball.” ~ Rachel Tan
What Causes Cataracts?
When cataracts occur in younger dogs (less than 6 years of age), it is usually hereditary. Cataracts can also develop from:
- diabetes: early detection and surgery is especially important with diabetic cataracts which can progress rapidly
- old age
- nutritional deficiencies
“My mom insisted on Nala having cataract surgery. It is costly. But knowing Nala will regain her vision is more important to my family. My mom, sis and I saved over 6 months for this surgery.”
Preparing The Eye For Cataract Surgery
Under general anaesthesia, the eyeball usually rolls back into the socket, making it inaccessible to the surgeon. An intravenous nerve block is administered which makes the eyeball rotate to the centre.
Staining The Lens Before Phacoemulsification
A small corneal incision is made to gain entry into the eye and a blue dye injected to stain the lens to make it clearly visible. Then a small window is created in the lens capsule through which the cataract is broken apart and removed via a procedure called phacoemulsification.
Inserting The Intraocular Lens (IOL)
Once the cloudy lens material is removed, the capsule is cleaned and polished. An artificial replacement lens is then inserted into the lens capsule. This will improve the vision of the patient tremendously.
Suturing The Corneal Incision
After the corneal incision is closed up with absorbable sutures, the patient is monitored closely as she recovers from anaesthesia. Post-operative eye medications are administered. Intraocular pressure (IOP) is measured at regular intervals to ensure it is within normal range.
how do i Care for my pet after surgery?
Vision usually improves within 24 hours and continues to improve over several weeks. Your pet will require the following:
- oral medication
- medicated eye drops
- an Elizabethan collar to prevent self-trauma to eyes
- re-examination of the eyes within 1 to 5 days, then 1 week after surgery, and again 2 weeks after surgery. Thereafter, the schedule for reviews is determined by the vet and progress of your dog’s recovery.
“When Nala got home last night, she started barking at everyone, probably because she has never seen us & our house before. We comforted her with our voices which she is familiar with. Today, she is much calmer.” ~ Rachel
No matter what our pets are living with, Dr Stanley says it beautifully: “We humans may feel sorry for ourselves. These animals, they just make the best of every situation.” But what a wonderful gift it is, to be able to help the blind see again!
Dr Heng Yee Ling, Mount Pleasant Animal Medical Centre (Farrer), graduated from the University of Edinburgh. During the course of her studies, she realised her interests in soft tissue surgery and in particular, veterinary ophthalmology. In 1997, she completed the Post Graduate Foundation Course in Veterinary Ophthalmology and has been performing cataract surgery for the past 3 years.
Dr Robin Stanley graduated with first class Honours from the University of Melbourne in 1984. He undertook an ophthalmology residency from 1987 to 1989, and in 1990, obtained his Fellowship of the Australian College of Veterinary Scientists in the field of ophthalmology. Dr Stanley is registered as a veterinary eye specialist and works in a dedicated ophthalmology-only practice in Melbourne. He consults and performs eye surgeries at Mount Pleasant Animal Medical Centre (Farrer) every quarter. Contact 6271 1132 for more info.
Epiphora is an abnormal overflow of tears from the eyes. It is usually caused by:
- obstruction of tear drainage system.
- overproduction of tears, often due to irritation or inflammation of the eye.
How are tears drained from the eyeS?
- Two small openings called punctae are present at the inner corners of each eye.
- Tears flow down these drainage holes into the lacrimal sac.
- From this sac, a small tube called the nasolacrimal duct carries the tears into the nose.
- The tears then drain to the outside through the nose.
If the tear ducts are blocked (like a blocked plumbing system), tears in the eye back up and overflow down the face, usually from the inner corner of the eye.
HOW DO I KNOW IF MY DOG’S TEAR DUCTS ARE BLOCKED?
A thorough examination shows that Megan’s eyes are looking good. The excessive tears could be due to a temporary irritation. For senior dogs like Megan, it is advisable to see the vet twice a year for a general health check.
what can be done for a blocked tear duct?
If your dog does have a blocked tear duct, the vet can perform a nasolacrimal flush. Eye drops may be prescribed. If the problem persists, a nasolacrimal catheter (small plastic tube) can be passed through the tear duct into the nose under general anaesthesia.
Glaucoma is a condition where there is increased pressure within the eye.
Inside the eye, cells produce a clear fluid (aqueous humor) that nourishes the tissues and maintains the shape of the eye. When there is proper drainage of the fluid into the bloodstream, normal pressure is maintained within the eye.
The problem starts when the drainage is partially or fully blocked. As the fluid continues to be produced but does not drain properly, pressure within the eye increases.
Glaucoma can be inherited or caused by different conditions including uveitis (inflammation of the eyes), lens displacement and retinal detachment. Lucky’s condition is caused by advanced cataracts which were untreated.
Being a painful condition, dogs with glaucoma may partially close or rub their eyes and avoid being touched. There may be eye discharge and the sclera (white of the eye) may look red.
Unfortunately, Lucky is already blind from advanced cataracts. Although his sight cannot be restored, medications can provide pain relief and offer him some comfort. Lucky will be on longterm medicated eyedrops to reduce both the inflammation and pressure within his eyes.
If the pressure remains elevated, enucleation (surgical removal of the eyeball) may have to be considered.
How is Lucky coping? As with most blind dogs, he is adjusting quite well to blindness by depending a lot more on his sense of smell and hearing. Once your blind dog has “mapped out” the house, try not to move furniture or other items around. Unique scents or little bells can also help your blind dog locate different areas or objects in the house.
The cornea is the clear, transparent part of eye that lets light into the globe, much like the aperture in a camera . The outer layer comprises several layers of epithelial cells which protects the rest of the cornea.
WHAT IS A CORNEAL ULCER?
Corneal ulcers are painful defects to one or more layers of the cornea – like a scrape wound on your skin.
- Superficial ulcers involve just the outer layer – epithelium. Uninfected ulcers heal rapidly (within 5 to 7 days) as the epithelial cells grow into the defect and new skin sticks to the underlying tissue.
- Deep ulcers extend into the middle layer – stroma – and take longer to heal. With deep ulcers, vision may be severely compromised or even lost. Often, intensive antibiotic therapy and surgery is required.
SOME CAUSES OF CORNEAL ULCERS
- Trauma: scratches, abrasions, puncture wounds
- Entropion: eyelids rolling inwards
- Keratoconjunctiva sicca: dry eyes
- Ectopic cilia hairs: fine eye lashes that point inwards
- Foreign body: an object sitting on the eye surface, e.g. a seed
SIGNS and SYMPTOMS
- Excessive blinking
- Eye discharge
- Pawing at the eye
- Redness of the conjunctiva
fluorescein stain test
Most ulcers can be diagnosed using a fluorescein stain. A green, non-toxic dye is applied to the surface of the cornea. On normal healthy eyes, the dye does not stain the corneal layer. If there is an ulcer, the dye adheres to the ulceration and illuminates bright green under a special light.
what is an Indolent corneal ulcer?
Indolent ulcers are usually superficial and non-infected but take a very long time to heal. New skin tries to grow over the ulcer but fails to adhere to the underlying tissue. With careful examination, a thin layer of loose tissue can be seen surrounding the ulcerated area.
Because the epithelial cells do not stick down to the tissue underneath, it is not possible for indolent ulcers to heal with just the use of antibiotic eye medications and artificial tears. Without appropriate treatment, indolent ulcers persist for months and cause ongoing discomfort.
In order for an indolent ulcer to heal, the loose tissue needs to be removed in a process called debridement. After local anaesthetic eye drops are applied, dry sterile cotton-tipped swabs are used to gently remove the loose abnormal epithelium surrounding the ulcer. This procedure may have to be repeated several times.
grid or linear keratotomy
If needed, grid or linear keratotomy is performed after debridement. A hypodermic needle is used to make superficial parallel incisions in the underlying exposed stroma. Simply put, we scratch the cornea with a needle to provide a rough surface for new epithelial cells to anchor onto and allow for proper healing.
Medications will be dispensed to prevent infection and control pain, and your dog will return for reviews until the ulcer is fully healed. Surgery for an indolent ulcer may have to be considered if it fails to heal after several attempts at debridement and keratotomy.