1001 Movies You Must See Before You Die list

1001 Movies You Must See Before You Die list

Ophthalmology Lecture - Eye Anatomy Part 1

Types of cataract.

Cataract may be classified on the
-basis of stage of development
(e.g. intumescent, mature, hypermature),

-anatomical position of the
opacity (e.g. cortical, nuclear, subcapsular), or aetiology (diabetic, traumatic)

In clinical practice all 3 classifications tend to be used when describing a
cataract e.g. marked corticosteroid-induced posterior subcapsular opacities.

1. Intumescent:

When lens fibres degenerate to form a cataract there is breakdown of lens proteins into smaller molecules so that water passes into the lens which then swells. Such a lens may become so large that it causes severe shallowing of the anterior chamber and may close off the angle of the anterior chamber causing 'phakomorphic' glaucoma.

2. Mature:

A cataract is described as mature when the whole lens is opaque and no clear cortex is visible with a slit lamp. The mature cataract appears white and although the visual acuity is reduced to light perception, the ability to identify the direction of the light source is retained (normal projection to light). (LCW 4.4 p58) This important observation must always be recorded in these cases, as it gives some indication of the visual prognosis of a possible cataract extraction.

3. Hypermature:

In this stage the fens capsule in a mature cataract becomes permeable to liquefied lens matter which then leaks out into theaqueous. The cataract shrinks leaving a small brownish nucleus surrounded by a wrinkled capsule (Morgagnian cataract). Macrophages invade the aqueous
and the lens from the systemic circulation, engulf the lens matter and subsequently block the trabecular meshwork resulting in a rise in intraocular pressure ('phacolytic' glaucoma). Sometimes the cells sink to the bottom of the anterior chamber to produce the appearance of a hypopyon (sterile). The degree and speed of the pressure rise is also very variable. Lens induced
uveitis (phakoanaphylactic uveitis), due to the development of antibodies to lens protein after lens matter leaks into the anterior chamber, is to be distinguished from phacolytic glaucoma, although it may complicate it. After control of the intraocular pressure with osmotic diuretic agents e.g. diamox or mannitol and of the uveitis with corticostcroids, a lens extraction is performed. These lens induced conditions may also arise following lens capsule
rupture due to trauma or as a complication of surgery.

Tips for a Successful Residency

Pearl #1: Read as much as possible

Dr. Ed Norton, the “father” of Bascom Palmer and who was a brilliant ophthalmologist and a respected chairman, was renowned for his knowledge of all aspects of ophthalmology. Dr. Norton’s secret was that he read something about ophthalmology every night (a chapter or a paper).

Many times, medical students will lose their drive to read and learn after their first two years of medical school. Among the factors that lead to this include: an expanded work-load (e.g., rounds, clinics, etc), the fact that so much learning occurs “on the job”, and that many students begin to have families that take up much of their free time. In addition, the internship year does not lend itself to reading as interns going into ophthalmology have little motivation to read during their non-eye rotations. Also, time pressures during internship make it a difficult time to read. Additionally, it is no small task to continue to read during the ophthalmology residency. Long days in clinic and the sharp learning curve can discourage even the best residents.
The most important thing to remember is that you only have three years to build the basis of your entire career. These fundamentals will be what you build on for the rest of your life. Don’t let a day go by that you don’t read something about ophthalmology, whether it is an article or a chapter or something online.

“What should I read?” is an excellent question. I recommend three types of reading: the American Academy of Ophthalmology’s basic science series (BCSC), journals, articles and book chapters about your patients.

The basic science series should be read each year and requires more “long-term” planning. You should try to get through one book per month. I tried to correlate and read the book with the type of rotation that I was on. It is best to put aside one hour a day to read from the BCSC.
Reading journals will establish the fundamentals that will keep you current throughout your career. It will also show your faculty that you are interested in staying current and have the discipline required to become an outstanding ophthalmologist. It is best to try and read the “Big 3”: Ophthalmology, American Journal of Ophthalmology, and Archives of Ophthalmology. In addition, when you are on a certain rotation, try to read the journal(s) specific to that rotation. One major advance that has made journal reading much easier is RSS feeds. An RSS feed allows you to find out when new articles or volumes of journals are available. It can be very hard to keep up with all of these journals, all of the time; hence, I would often read the abstracts and spend more time focusing on articles I found valuable.

Reading on your patients will not only help your patients, but will also help you learn and remember the diseases you are studying. If you see an interesting case of an unusual diagnosis, then read on it. You will never forget the specifics about a disease if you have seen it first hand.

Pearl #2: Prepare to be overwhelmed

This is especially true for first year ophthalmology residents. You enter into a new field knowing nothing about the examination or the diseases you are about to encounter. In many ways, medical school and internship does little to prepare you to survive your first few months of an eye residency.

You can prepare yourself in several different ways. The first way is to spend time during your internship reading about ophthalmology. It is great if you can get your BCSC series during your internship and read it during that year. Many programs will give you a copy of the BCSC only once you start your residency. It is worth calling them to see if they can provide it to you in advance. If you cannot get the BCSC, the next best option is to read a text with good photos and basic descriptions of diseases. Kanski has written an excellent text that I read during my internship: Clinical Ophthalmology: A Systematic Approach (Hardcover). It has great photos of almost all the conditions you are likely to encounter in residency.

Another book I highly recommend is Practical Ophthalmology: A Manual for Beginning Residents (Paperback) by Dr. Fred Wilson. This book discusses the fundamentals of examination techniques (e.g., refraction, applanation, slit lamp examination, etc.). Many residency programs will supply this book to you at the initiation of your residency. It would be worthwhile contacting your residency program director to see if you could obtain a copy of this book prior to starting residency.

It is important to understand that the first few months are very overwhelming and that with time, you will learn the fundamentals of the examination and things will get much easier. Also realize that your fellow residents are going through the same process. Enjoy and embrace the many things you are about to learn ( e.g., refraction, indirect ophthalmoscopy, cataract surgery, etc.).

Pearl #3: Be a good assistant

Dr. Wallace Alward, a glaucoma specialist at the University of Iowa, gave me a valuable “pearl of wisdom” early on during my second year of residency. He told me that he could often determine the best resident surgeons by observing how they assisted with surgery early on in their careers. Having worked with residents and fellows, I can now appreciate what he meant with this comment.

A good assistant in surgery will have an in-depth knowledge of the surgery being performed. A resident who demonstrates that they understand every step in the procedure, is much more likely to get the chance to operate than one who “just shows up”. Anticipation of the next step, having suture or scissors ready to cut, keeping the cornea well lubricated, and holding the eye in proper place are all ways that you can show that you have a good understanding of how to approach the surgery. Being a good surgeon is not about how steady your hands are, it is about being able to anticipate and avoid complications. It is also about knowing how to deal with complications when they occur. In my mind, being a good surgeon is similar to being a good airplane pilot. Any qualified pilot can take off, fly a route, and land; the difference between an average pilot and a great one comes out when there are problems. The great pilot is more likely to safely deliver the passengers to their destination when there are problems, such as when the weather is poor or when there are mechanical problems. You can learn a lot simply by observing and being a good assistant.

In addition, a resident who makes the staff surgeon’s life easier is more likely to have an opportunity to operate on his or her patients. It is easy to feel as though you work hard on call, in the clinic, and the OR and that you deserve to get to do more surgery. Always remember that these are not your patients and that if a complication occurs, you will not have to see that patient for the rest of your career. Keeping this in mind will allow you to see the opportunity you have during your residency to learn surgery from your mentors.

Pearl #4: Be available

This sounds easy, but is often times overlooked by residents. Being available for your co-residents, faculty members, technical staff, and patients is one of the most under-rated parts of being a good resident. There is nothing more aggravating for a faculty person who needs help with or vital information about a patient than to have the resident be unavailable. Another disheartening thing is when there is a great teaching case, but the resident has left for lunch or to go home. You should not leave the clinic (for lunch or for home) until all the patients have gone.

I can recall one instance from my residency, when I was on call and a trauma patient arrived with interesting eye findings. This patient arrived shortly after the end of our evening lecture and most residents headed home. The oculoplastics attending and I headed to the ER to see the patient. Along the way we encountered a second year resident that was on his way home. He asked what we were going to do and when we told him about the interesting case, he immediately came along. That act earned him more respect with the attending surgeon and showed that he was not just a “9 to 5” resident who would rather get home as soon as work was over. It also showed that he had a true interest in ophthalmology.

If you are available, you will see more interesting cases, learn more ophthalmology, and have the opportunity to do more. Along these same lines, you should never turn down the chance to go to the operating room. One of the best parts of ophthalmology is getting to operate, and residency is the time to hone your skills in the presence of “battle-tested” staff members. When you are on your own in practice and come up against a tough case (especially trauma), you will reference your surgical experiences the most. The more cases you do under guidance, the more wisdom you will have when you encounter these tough scenarios.

Pearl #5: Leave your ego at the door

The biggest obstacle for many physicians is that they let their “ego” get in the way of learning, interaction with staff, and patient care. An ophthalmology residency is tough to get. Most residents are in the top quarter of their medical school class and are very accomplished academically. Patients like physicians that have confidence, but somewhere along the line this confidence can turn into arrogance. Most of the failed interactions that I have observed between faculty members, staff, and with unhappy patients results from the almighty “ego”. Sometimes it is just something as small as not being willing to apologize for keeping a patient waiting too long. Other incidents can be more serious (e.g., arguments with staff in the OR, heated discussions during rounds, or refusal to see patients on call) and can lead to serious detrimental effects on the health care team. When things seem to be getting a bit “heated”, I will often try to separate myself from the situation and ask myself if my ego is affecting my stance on something and then try to eliminate it from my view of what is going on. It is amazing how effective this can be and how it can turn a potentially bad situation into something very positive. Finally, don’t ever hesitate to admit when you are wrong. Everyone has missed a diagnosis, made a patient wait too long, or been wrong about an assumption that lead to an argument. The key thing is to learn from this and not repeat the same error.

These are just a few tips for not only being a good resident, but also for getting the most out of your residency. Most of these lessons were learned as I went through my residency. I hope they can help you to avoid some of the potential pitfalls of training. Ophthalmology is a great specialty, and there are a lot of physicians that would love to have the same opportunities that we have. Don’t ever take for granted just how fortunate you are to have the opportunity to do ophthalmology as a career.

Cranial nerves.

Olfactory I
Optic II
Oculomotor III
Trochlear IV
Trigeminal V
Abducens VI
Facial VII
Auditory (vestibulocochlear) VIII
Glossopharyngeal IX
Vagus X
Spinal Accessory XI
Hypoglossal XII

Extraocular muscles and nerves

CN III damage––eye looks down and out,
CN IV damage––diplopia with downward gaze.
CN VI damage––medially directed eye.

CN VI innervates the Lateral
muscles and nerves Rectus.
CN IV innervates the Superior Oblique.
CN III innervates the Rest.

The “chemical formula”
LR6SO4R3.

The superior oblique abducts, intorts, depresses.