General Flashcards Preview

ChM > General > Flashcards

Flashcards in General Deck (16):
1

3 structures posterior to the septum

- palpebral lobe of lacrimal gland
- lateral canthal tendon
- trochlea of SO

2

What is the arcus marginalis

Where septum fuses with peri-orbita at the orbital rim

3

What are the two vascular arcades of the upper lid

Marginal arcade: at the eyelid margin
Peripheral arcade: just above the top of tarsus (behind levator, in front of muller --> be careful not to hit it in ptosis repair whn you take a bite through levator!)

4

MRI, T1 is what colour for vitreous and orbital fat?

Vitreous dark on T1, bright on t2

Orbital fat is bright on T1, but turns dark with fat suppression (allows you to see optic nerve better)

5

Silicone oil

Band keratopthy
If emulsified: glaucoma, direct effect on endothelium.
Worse in a phakic patients.

Know that there are 2 types of viscosity to the oil (alters calculation)
If traditional a scan ultrasound moves slower and the eyeball will read longer than it is (you'll need a higher power lens)
Others thibgs: lens choice (calculations, power spericity,

6

Where is a schwannoma on the eyelid usually?

Solitary nodule near medial canthus

7

List orbital choristomas

Tumors of tissues NOT normally found there

- dermoid
- dermatolipoma
- ectopic lacrimal gland
- complex conjunctival choristoma

8

There is a solitary nodular cyst at the lateral canthus. What is it?

Hydrocystoma

- either on lid margin or lateral canthus
- solitary nodular cyst
- lined by double row of cuboidal epithelium

9

5 causes of correctopia

Trauma
Posterior synechiae (inflammation)
ICE
Axenfeld reiger
Ectopia lentis et pupilae

10

Differential of congenital hypochromic iris

Wardenburg
Horner's
Hirschprung
Parry Romberg hemifacial atrophy

11

Congenital unilateral hyperpigmented iris

Ocular or oculodermal melanocytosis
Iris pigment epithelial hamartoma

12

When do you see a Kayser Fleischer ring

Wilson's disease
Chalcosis (foreign body)
Multiple myeloma
Lung carcinoma

13

What is the max dose of lidocaine you should use

5 mg/kg no epi , max dose 300 mg
7 mg/kg with epi, max 500 mg

14

DDx of intra-ocular calcium

Phthisis
RB, retinocytoma
ONH drusen
Choroidal osteoma
Choroidal hemangioma
Retinal astrocytoma

15

DDx of intra-ocular cartilege

Trisomy 13
Medulloepithelioma
PHPV

16

List orbital hamartomas

Tumors of tissues NORMALLY found in that location

- nevus
- neurofibroma
- neurilemmoma = schwannoma
- glioma
- hemangioma
- lymphangioma
- CHHRPE