Vision & Eye Health guides
Practical, veterinary-led guidance on Vision & Eye Health, written by vets, free to read. View all guides
Is Cataract Surgery Right for My Pet? A Decision Guide
Your vet has said the word cataract, and now you're trying to work out whether to operate. The search results don't help much. On one side sit the websites with a stock photo of a bright-eyed dog and a headline promising to restore your pet's sight, with a price quietly bolted on. On the other...
Alastair Greenway, BVM&S MRCVS · 12 min read
Diabetic Cataracts: Why Most Diabetic Dogs Go Cloudy, and Why Speed Matters
A dog is diagnosed with diabetes, the owner gets the injections and the feeding times right, and a few months on the eyes start to cloud. I've taken that phone call many times, and underneath the worry there's nearly always the same quiet question: did I do this? The honest answer is no. You almost...
Alastair Greenway, BVM&S MRCVS · 13 min read
Questions to Ask Your Ophthalmologist About Cataract Surgery
A cataract consult is a big appointment, and it costs real money. Over the years I've sent a lot of owners to these consults, and the ones who get the most out of them are the ones who arrive prepared: questions written down, someone alongside to take notes, and no willingness to be rushed. Nobody...
Alastair Greenway, BVM&S MRCVS · 11 min read
Cataracts in Cats: Less Common, Usually Secondary
The word "cataract" tends to drag a fixed picture along with it: the one you carry from people, or from a dog you once knew. A clouding eye, creeping blindness, an operation. I'd like to take that picture apart, because the feline story is genuinely different, and once you see how, the whole thing becomes...
Alastair Greenway, BVM&S MRCVS · 10 min read
If You Don't Operate: Living With a Pet With Cataracts
Many owners reach this decision quietly, and often with a flicker of guilt. The surgery is specialist, it isn't cheap, your pet may be older or not the ideal candidate, and somewhere at the back of your mind sits the worry that by not operating you're "letting them go blind". That worry deserves a straight...
Alastair Greenway, BVM&S MRCVS · 10 min read
What Cataract Surgery Involves, and Recovery Week by Week
The hard part is usually behind you by the time you want this page. The agonising over whether to operate, the cost, the "is it the right thing for my dog", that all belongs to the decision, and if you're still weighing it up, the operate-or-not piece is the place for it. What I want...
Alastair Greenway, BVM&S MRCVS · 11 min read
Cataracts in Dogs and Cats: What They Are and Why They Form
"Cataract" is a heavy word, and owners tend to hear the worst of it first. But there's often relief mixed in too, because they'd been peering into that cloudy eye for weeks fearing something dreadful, and now at least it has a name. So before we get anywhere near decisions, let me do what I'd...
Alastair Greenway, BVM&S MRCVS · 13 min read
Removing a Blind, Painful Eye (Enucleation): Kinder Than It Sounds
The word lands hard across the consulting table. Enucleation. Eye removal. What most owners picture is something brutal being done to a pet who's already suffering. They feel they've failed, they feel they're agreeing to a mutilation, and they're grieving the eye before it's even gone.
Alastair Greenway, BVM&S MRCVS · 11 min read
Glaucoma in Dogs: The Painful Emergency Owners Miss
One thing here cannot wait two minutes, so it goes first. If your dog has an eye that's suddenly turned red, cloudy or hazy, that looks bigger or more bloodshot than the other one, that they're squinting or rubbing, or that seems to have stopped seeing, ring your vet now and say you think it...
Alastair Greenway, BVM&S MRCVS · 14 min read
Managing Glaucoma at Home: Drops, Pressure and What to Watch
Three bottles, several times a day, one eye, then a wait, then another drop. By now the diagnosis is probably behind you, and what wears you down is the daily grind of it: the small anxious voice asking whether you got the timing right, or whether today's the day the eye flares up while you're...
Alastair Greenway, BVM&S MRCVS · 12 min read
Uveitis: When the Inside of the Eye Is Inflamed
What started as "a sore eye" has turned into a conversation about blood tests, and that swerve can feel baffling. Here is why it isn't.
Alastair Greenway, BVM&S MRCVS · 11 min read
The Fellow Eye: Protecting the Second Eye in Primary Glaucoma
One eye has gone, or is going: a glaucoma diagnosis, a sudden painful attack, perhaps an operation to remove a blind, sore eye and end the pain it was causing. And now, in among the relief and the grief, a new worry has crept in. The other eye. Is the same thing coming for it?
Alastair Greenway, BVM&S MRCVS · 11 min read
Spotting Eye Pain in Pets: The Signs We Overlook
The eye that worries me most on the consult table is often the one that has stopped looking sore. An owner brings a dog in because they have finally noticed a slight squint, and they apologise for wasting my time. They have not wasted my time. More often than not, that quiet, half-shut eye has...
Alastair Greenway, BVM&S MRCVS · 10 min read
Glaucoma in Cats: Nearly Always Secondary
Glaucoma in a cat is a different animal from glaucoma in a dog, and that difference is the whole point of this page. In dogs it's often a dramatic emergency: a red, bulging, agonising eye that comes on over hours, frequently with no underlying cause we can name. That story belongs to glaucoma in dogs....
Alastair Greenway, BVM&S MRCVS · 11 min read
My Cat Suddenly Went Blind: Check the Blood Pressure
A cat that has, in the space of a day or even overnight, started walking into furniture, missing the sofa, freezing in the middle of the room with both pupils wide and black needs one thing from you before any of the biology. So I'll give you that first.
Alastair Greenway, BVM&S MRCVS · 12 min read
My Pet Suddenly Went Blind: What to Do Right Now
Here is the short version, because it matters more than anything else on this page. Sudden loss of sight needs to be seen today, not at the weekend, not "if it's no better in a few days." Ring your vet or the nearest emergency clinic now and tell them your pet has suddenly gone blind....
Alastair Greenway, BVM&S MRCVS · 10 min read
Sudden Versus Slowly-Noticed Blindness: Why It Matters
"It happened overnight, doctor. One day she was fine, the next she was walking into the furniture." It's one of the most common things owners say when an older pet has lost its sight, and it nearly always comes with a flush of guilt. They're braced for me to confirm their worst fear, that they...
Alastair Greenway, BVM&S MRCVS · 11 min read
High Blood Pressure and Your Pet's Eyes: The Link Owners Miss
High blood pressure sounds like a human problem, the sort of thing a doctor raises at a midlife check-up. So when I tell an owner that their cat's sudden blindness, or the red haze that appeared in their dog's eye overnight, comes down to blood pressure, the reply is nearly always the same: "pets get...
Alastair Greenway, BVM&S MRCVS · 12 min read
Retinal Detachment: Causes, Urgency and What Can Be Saved
"Detached retina" is a phrase that lands hard. Say it across the consulting table and most owners picture an eye coming apart, sight gone for good in an instant. The real picture is calmer than that. A detached retina is a layer coming unstuck, not an eye falling apart, and whether anything can be saved...
Alastair Greenway, BVM&S MRCVS · 11 min read
SARDS: Sudden Blindness in Dogs With No Warning
A dog who was fine last week is suddenly walking into doorframes. The eyes look completely normal, there's no redness, nothing obviously hurts, and yet the dog plainly cannot see. This is one of the handful of diagnoses I genuinely dread giving. The owner is searching for an accident to explain it and there isn't...
Alastair Greenway, BVM&S MRCVS · 11 min read
Other Inherited and Gradual Eye Conditions
"Inherited eye condition" is a phrase that lands in two ways. Sometimes a vet, a breeder or a forum post has attached a scary-sounding name to your breed, "collie eye", "lens luxation", "the Staffie cataract", and you've come to find out what it actually means. Sometimes you're doing the careful thing of researching a breed...
Alastair Greenway, BVM&S MRCVS · 11 min read
Preparing for Blindness When You Know It's Coming
A diagnosis like progressive retinal atrophy, or a slowly thickening cataract, lands hard. Someone has told you, in so many words, that your dog or cat is going to lose their sight over the coming year or two, and there's no operation or eye drop that will stop it. A few days on from that...
Alastair Greenway, BVM&S MRCVS · 10 min read
PRA and Your Breed: DNA Testing and What It Means
The most common question I get about PRA rarely comes from someone whose dog is already losing its sight. It comes from someone holding a puppy's paperwork, or thinking about a litter, reading the phrase "PRA clear" or "carrier" and quietly panicking. "My breeder says the puppy is clear, does that mean it can't go...
Alastair Greenway, BVM&S MRCVS · 10 min read
Progressive Retinal Atrophy (PRA): Slow, Painless, Inherited
A PRA diagnosis arrives differently from most. There's no accident to point to, no emergency dash to the vet, no painful eye to treat. Just a quiet sentence in the consulting room that says, in effect, your dog is going to lose its sight, slowly, and there's nothing we can do to stop it. I've...
Alastair Greenway, BVM&S MRCVS · 11 min read
Your Pet Has Gone Blind: The First 30 Days
Let me say the most important thing first, because you may be reading this at three in the morning with a frightened animal in the next room. Your pet's life is not over. This feels like a catastrophe right now, and I won't pretend the next few weeks are easy, but blind dogs and cats...
Alastair Greenway, BVM&S MRCVS · 11 min read
Out and About: Walks, Safety and Telling Other People
One of the first questions I'm asked, once the shock of the diagnosis has settled, is some version of "can he still go for walks?" The answer is yes, wholeheartedly. A blind dog can have a full, busy, joyful life outdoors: parks, new places, the smell of next door's barbecue, the lot. The world doesn't...
Alastair Greenway, BVM&S MRCVS · 10 min read
Halos, Mats and Aids: What Actually Helps (and DIY Options)
Almost every owner I see arrives at the same practical question once the diagnosis has settled, usually with a browser tab or two already open: is one of those halo things worth it, and what actually helps? That deserves a straight answer rather than a sales pitch. The trouble is that the loudest voices here...
Alastair Greenway, BVM&S MRCVS · 11 min read
Blind Cats: Why They Often Cope Brilliantly
Here's the one sentence I most want a worried cat owner to hear, because it tends to get buried under the panic. A blind cat can live a full, happy, ordinary life, and most do. The UK charities that see thousands of these cats say it plainly: "blind cats can live a full life and...
Alastair Greenway, BVM&S MRCVS · 13 min read
Will My Blind Pet Be Happy? Quality of Life and What to Expect
The question I'm asked most after a blindness diagnosis isn't about the eyes at all. It usually comes a few weeks in, once the appointments are done and the house has gone quiet. "Will she still be happy?" And underneath it, almost always, the one nobody says out loud: am I keeping them going for...
Alastair Greenway, BVM&S MRCVS · 12 min read
Talk Before You Touch: Communicating With a Blind Pet
A newly blind pet will often flinch, snap or scramble up in a panic when a familiar hand reaches in to stroke them in their usual spot. Owners describe this to me again and again, and it catches them off guard, because nothing has changed in their kindness. What has changed is that their pet...
Alastair Greenway, BVM&S MRCVS · 12 min read
Home-Proofing for a Blind or Low-Vision Pet
The diagnosis is settled, your dog or cat is losing its sight, and now you're home with the practical question: what do you actually do here? This is my favourite part to answer, because it's the part you control. The diagnosis was out of your hands. The home isn't. With a weekend of small, sensible...
Alastair Greenway, BVM&S MRCVS · 13 min read
My Pet's Eye Looks Cloudy: Should I Worry?
A cloudy eye usually shows itself in a particular kind of light. Your old dog is dozing in the afternoon sun, or your cat is on the windowsill with the light catching just right, and you see it: a soft bluish-grey haze deep in the eye where there used to be clear black. The word...
Alastair Greenway, BVM&S MRCVS · 12 min read
Is This an Eye Emergency? A 60-Second Check
An eye has gone cloudy, or red, or your pet is holding it half shut, or they've started bumping into the coffee table they've walked past a thousand times. Underneath whichever sign you're looking at sits one practical question: do I need to act now, or can this wait until morning? I've taken that phone...
Alastair Greenway, BVM&S MRCVS · 10 min read
How Sight Works in Dogs and Cats (and How It Differs From Ours)
I've spent more than twenty years looking into the eyes of dogs and cats, and they still amaze me. Not because they see better than we do, because in most of the ways we tend to value sight, they don't. They amaze me because they see the world so differently, and because the eye turns...
Alastair Greenway, BVM&S MRCVS · 10 min read
Signs Your Dog or Cat Is Losing Their Sight
Owners almost always apologise when they bring me a pet whose sight has been quietly failing. "I feel terrible, I only just noticed." "She's been bumping the corner of the sofa for weeks and I put it down to clumsiness." There's usually a thread of guilt in it, the worry that a good owner would...
Alastair Greenway, BVM&S MRCVS · 11 min read
Red, Painful or Squinting Eye: What It Might Be and How Urgent
A sore eye, half-shut and weepy and a bit pink, raises one practical question above all others: is this a "ring first thing tomorrow" or a "get in the car now"? Of all the things owners try to judge from the sofa, a red eye is one of the genuinely hard ones. It can look...
Alastair Greenway, BVM&S MRCVS · 11 min read
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