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Ophthalmology

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H/O Unilateral progressive proptosis for many years...swelling is increased on bending forward and compressible....USG shows retrobulbar echogenicity. (AIIMS May 2010)



A Orbital varix

B Orbital A-V fistula

C Neurofibromatosis

D Orbital encephalocele

Ans. A Orbital Varix

(Oxford handbook of opthalmology,2nd edition)

Orbital varix

1. Venous enlargements

2. From childhood

3. Usually u/l

4. Located in medial orbit

5. Intermitent proptosis-worsened by increased venous pressure as with valsalva manoeuvre.

A-V fistula

1. High flow or direct communication between intracavernous I.C.A and cavernous sinus.

2. Low flow or dural shunts b/w dural arteries and cavernous sinus.

3. Audible bruit

4. Pulsatile proptosis

5. Other complications of increased pressure in the cavernous sinus- conjunctival edema(chemosis), raised IOP, nerve palsies.

6. Imaging shows enlarged superior ophthalmic vein(due to arterialisation) and thickening of extraocular muscles.

Neurofibromatosis

a. Pulsatile proptosis(due to sphenoid wing dysplasia leading to transmission of brain pulsations to the globe.

Ocular features of NF-1

a. Optic glioma

b. Lisch nodule(iris hamartoma)

c. Lid neurofibroma

d. Choroidal nevi

e. Retinal astrocytoma

Ocular features of NF-2

a. Early onset posterior subcapsular or cortical cataract

b. Combined hamartoma of the retinal pigment epithelium and retina

Hamartomas-excessive focal overgrowth of mature normal tissues is their normal location

Orbital encephalocele

a. Soon after birth

b. Soft mass near the canthus

c. Pulsatile and increase with valsalva

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