Teaching August 2017

Rather than run a live microscopy session this month, I instead ran a half day teaching session last week for the new (and not so new!) ophthalmology trainees at Moorfields. This took the form of a quiz, looking at differential diagnoses of exam-type cases, using audience response system handsets from Qwizdom. I’d never used this technology before, and I thank the guinea pigs in the audience for participating with such good humour. If you did attend last week’s teaching and would like to offer suggestions on what you’d like in the next session, please feel free to contact me using the form at the end of this post.

Here are a few of the cases we discussed.

Case 1 – cornea

Middle aged patient with gradual decrease in visual acuity.


This section shows full thickness cornea with a rather subtle loss of the stromal basket-weave pattern, suggesting oedema. There is reduction in endothelial cell numbers.

Cornea (PAS)

The PAS-stained section shows protrusions on Descemet’s membrane – exophytic guttae.

This is Fuchs’ endothelial dystrophy.

Case 2 – cornea

Young patient with increasing astigmatism, and an acute episode with pain more recently.

Cornea (low power)

This low power view shows irregular thickness of both the epithelium and stroma, with stromal scarring and loss of basketweave pattern. There is a protrusion on the posterior surface…

Cornea (PAS)

…which a higher power PAS shows to be a healed break in Descemet’s membrane with scrolling and some regeneration.

This is keratoconus with previous hydrops and scarring.

Case 3 – globe

This is a rare finding in an enucleation specimen!

Globe (low power)

On low power, there is a dense cellular infiltrate within the iris and ciliary body (to the left) and extending into the choroid (right).

Globe (medium power)

On higher power, the infiltrate is vaguely nodular, with rather uniform small lymphoid cells. The overlying retina is uninvolved by the infiltrate but oedematous.

This looks like a lymphoma, and immunohistochemistry (not shown) gave a pattern consistent with extranodal marginal zone lymphoma.

I hope these cases are a useful reminder of what we covered, and maybe whet your appetite for my next live microscopy session on 12 September. Feel free to contact me with any comments or questions.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.