Microscopy session October 2016

Thanks to everyone who participated in this month’s teaching session. This was our first session with the new teaching microscope system which has been very kindly funded by Friends of Moorfields. The new system means that we can cater for a much larger attendance than previously. This month we had attendees from Moorfields, from the Royal Veterinary College and from corneal and genetics research groups within the Institute of Ophthalmology, leading to some interesting discussions!

 

Here are some highlights of the session.

Case 1

Cornea from a young adult

This is a low power image of a full thickness cornea. Even at this power, you can see there is central epithelial thickening and stromal thinning. The diagnosis is keratoconus.

Case 2

Fornix anatomy

This is a low power image of the upper fornix from an exenteration specimen to illustrate some normal anatomy. The sclera of the globe is on the right, with eyelid to the right. In the central part of the image are bundles of smooth muscle interspersed with fat. This is Müller’s muscle. Below it, just to the left of the forniceal conjunctiva, is lacrimal gland (palpebral portion).

Cases 3 – paired

2 globes

This is a choroidal melanoma with prominent epithelioid tumour cells. The tumour cells are discohesive – space can be seen around individual cells. The nuclei are pleomorphic – irregular in size and shape – and there are prominent nucleoli.

We had some discussion on the differences in appearance between epithelioid and spindle cell melanomas. For comparison, this is a melanoma with spindle cell morphology. The nuclei are more uniform in appearance compared with the epitheloid tumour.

Cases 4 – paired

2 orbital biopsies from patients with previous interventions

This first biopsy has fibrofatty tissue with the striking feature of black material deposited within blood vessels and some surrounding chronic inflammation.

In the second biopsy, there is also deposition of foreign material within blood vessels and surrounding inflammation. A multinucleate giant cell is visible on the lower left.

Both of the patients have had embolisation of orbital vascular malformations before surgery. Presumably the material used in the procedures differed between cases, and I guess that onyx was used for the first case. I would welcome comments on what materials might be used in these cases.

Case 5

This is an enucleation specimen from a young child.

The low power view shows a sizeable tumour within the posterior segment (cornea, iris and lens are towards the left). The tumour arises within the retina and has a “small round blue cell” appearance with areas of necrosis (pink).

At higher power, rosettes are visible.

I hope everyone found the session (and biscuits!) interesting and enjoyable. And again, huge thanks to Friends of Moorfields for making this and future sessions possible! See you next month!