Saturday, March 14, 2015

The early steps I become an eye doctor

Plenty of people around me wear glasses. Both my parents are myopic, as are all my siblings. (Interestingly, none of my 4 grandparents were myopic, but this is a topic for another day) I'm not sure, but perhaps this constant reminder of our bodily imperfections was the beginning of an interest in the eye and vision.

My paternal grandmother had cataract surgery back in the 60s, and in those days the norm was large incision ICCE followed by thick aphakic glasses. I was always amazed that she could see through those glasses, which looked pretty much like the magnifying glasses we played with to focus light and make small burns with sunlight. Sadly, in her later years, her vision dimmed as her corneas became swollen from aphakic bullous keratopathy.

However, I hadn't exactly set my mind on ophthalmology at the time I set off to Melbourne for medical school. My eventual career goal was actually quite fuzzy at the time, and medicine was relatively reassuring as a stable career which I was familiar with through my father's occupation. I knew it could be a very satisfying job as well.

Where I stayed-49, Haines Street, North Melbourne. It was a 15 minute walk to the medical faculty at Melbourne University

As a medical student, I initially found it quite discouraging to study ophthalmology. We had all of 2 weeks attached to an eye unit. When the doctors looked at the eye, we could not usually see what they were looking at. And they were not very interested to show us how to use the instruments.

slit lamp microscope
How does the doctor focus the slit lamp microscope??-One of the many mysteries I faced while watching eye doctors at work as a medical student...

John Llewellyn Colvin
John Colvin, Ophthalmology teacher extraordinaire
In my clinical years I heard about John Colvin's lectures on Saturday mornings, and started attending them, if only to ensure that I had a basic competency in ophthalmology when I graduated. I was grateful for his handouts, and for making a pretty mysterious subject understandable. I was also fascinated by his aviation anecdotes, and he kept us awake by the use of the bugle and gong. It was a highlight of my medical school years.

By my final year of medical school I started to seriously entertain thoughts of specialising in ophthalmology as a career. My father was pretty encouraging in this respect as well. Studying for and winning the RANZCO Ophthalmology prize for Victoria in my final year of medical school more or less sealed my decision to embark on this as a career.

Most people would prefer staying in one place for their career, however, I became a bit of a nomad after graduating from Melbourne University in 1997. Medical school was followed by House Officer posts in Stoke-on-Trent and Glasgow, the United Kingdom. While in Glasgow, I started applying for and going to interviews for Senior House Officer (SHO) posts in ophthalmology. I got an offer from Northampton, which resulted in an overnight drive from Glasgow to Northampton at the end of February 1998. Along the way, I dropped my wife off at St Mary's Hospital in Manchester, where she had obtained a job in obstetrics and gynaecology. Yes, we made our minds up pretty quickly about our areas of specialization!

It was one long night's driving for me, with the sum total of our possessions packed in the car boot

At Northampton, I was introduced to Mr Pierre Hein, who took me through my first ECCEs (extracapsular cataract extractions-punctuated by cigar and coffee breaks in between cases, when sagely advice would be given), and Mr Ian Fearnley, who introduced me to phacoemulsification cataract surgery. Mr Atkinson had a 'photo clinic', where cases with prominent clinical features were present and we, the junior doctors were given grillings...

There were moments of excitement unrelated to ophthalmology too-Michael Schumacher broke both his legs at Silverstone that year (1999) when his F1 car speared into the barriers. He was airlifted to where else but...Northampton General Hospital! Sadly, I was not able to penetrate the barriers to have a good chat with him-it was one of the rare occasions where I thought of doing orthopaedic surgery instead...

The nomadic lifestyle continued, with interesting sojourns to Windsor (watching Concorde fly overhead was a truly earsplitting experience), followed by the major part of my Basic Specialist Training at Manchester Royal Eye Hospital.

But finally, with the impending birth of our eldest daughter, we sought to return to Singapore, where we had my in-laws to help take care of the baby, and easier access to domestic help.

Sunday, March 8, 2015

Cuts of the eye and first aid tips

Corneal lacerations-cuts to the eyeball

Mr L, a trainee carpenter, was trying to remove a nail from a piece of wood. He was thinking of getting off early that day, because of a date that evening to celebrate his girlfriend's birthday. As he levered the nail with the claw of the hammer, he suddenly felt it give and the nail flew off, straight into his eye.

The cornea is the clear window at the front of the eye. It is also the part of the eye closest to the object being looked at. 

Being constantly exposed to the environment, corneal injuries are a fairly common problem. They range from foreign bodies such as metallic particles from drilling or welding work, to abrasions/scratches, lacerations and chemical injuries.

Corneal lacerations occur when a sharp object cuts or pokes the cornea. They may be partial thickness, or they may go through the full thickness of the cornea and affect the inner parts of the eyeball.

Apart from direct damage to the eye, corneal lacerations are serious injuries which may also damage the eye by causing an infection, or impair vision because of corneal scarring after the eye heals.

Causes of lacerations

Common causes include flying objects, which may happen, for example with a nail as above or while cutting grass with an uncovered mower and while drilling and hammering. Broken glass from road traffic accidents are also a notorious cause of lacerations.

At the time of injury, a severe sharp pain will be felt as the cornea is one of the most sensitive parts of the body. There is almost always a clear history of a foreign object cutting or flying into the eye.
After the injury, vison is commonly blurred, especially if the laceration is deep and close to the centre of the cornea. There may be increased sensitivity to light, tearing, and it may be difficult to open the eye.

What the doctor will do to examine the eye

The doctor will usually instil some local anaesthetic eyedrops first to numb the eye and allow comfortable examination. Usually a careful examination on a slit lamp microscope then follows, with the doctor determining whether there are any remaining foreign bodies, and also very importantly, the depth of the laceration. If the cornea suffered a full thickness cut, fluid may leak from inside the eye, or internal parts of the eye such as the iris may protrude outwards.

A full thickness laceration has occurred in the centre of Mr L's eye. The nail penetrated the cornea, and also the lens of the eye, which has become a trauma induced cataract. Fine black nylon stitches were used to close the laceration.

Treatment of corneal lacerations

First aid for suspected corneal lacerations
  • ·         Do not attempt to remove any foreign bodies or what appear to be foreign bodies/dirt (protruding parts of the eye may look like foreign bodies or dirt)
  • ·         Do not wash or press on the eye
  • ·         If possible, obtain an eye shield or fashion one from a plastic cup. This is easily done by cutting the cup around the rim about 1-2cm from the bottom, so that the cup now only has a shallow rim. (see below)
  • ·         This can be taped so that the rim rests on the bony edges of the eyebrow and cheek.
  • ·         Send the patient straight to a specialist eye clinic or the emergency department.

Cuts of the cornea require different types of treatment, depending on how long or large they are, and even more importantly, whether the eye is penetrated.

If the cut is small and only affects a partial thickness of the cornea, it is treated like a corneal scratch or abrasion. Usually, this type of injury heals well with some antibiotic eyedrops to prevent infection, and the removal of any remaining foreign bodies. A bandage contact lens is sometimes used to protect a long shelving laceration.

For a corneal laceration that cuts through the full thickness of the cornea, the situation is more complicated. Usually, the first step, which is performed by the eye surgeon in an operating theatre, is to clean the wound and to stitch up the cornea so that there is no longer any fluid leakage from the eye. If there is internal tissue protruding from the eye, this is carefully repositioned into the eye when possible. Where there is more extensive damage such as lens damage causing a cataract, this may be dealt with at a second stage when tests are done to allow selection of the most suitable lens implant for the patient.

Mr L had his corneal laceration stitched up, followed by a cataract removal operation and lens implant. He now has good vision in that eye, however, due to the cataract surgery now has 'presbyopia' in that eye because the lens implant cannot autofocus like his original lens could before.

Prevention of corneal lacerations

·      These injuries can be prevented by wearing protective eyewear when engaging in activities such as grass cutting, hammering or drilling.

Corneal lacerations are potentially very serious injuries of the eye. Besides possible internal eye injuries, infections can also occur and lead to impaired vision. Do take care and use safety eyewear when engaging in hazardous activities, as the old adage ‘prevention is better than the cure’ certainly holds true here.