October 13, 2010

Q&A: Diagnosis involving Photophobia and Sectoral Hyperemia

Hyperaemia (also hyperemia) is the increase of blood flow to different tissues in the body. It can have medical implications but is also a regulatory response, allowing change in blood supply to different tissues through vasodilation. Clinically, hyperaemia in tissues manifest as erythema (redness of the skin) because of the engorgement of vessels with oxygenated blood. Hyperaemia can also occur due to a fall in atmospheric pressure outside the body.

This article is for Medical Students & Professionals
This is a Question & Answer revision article designed for medical students and professionals preparing for the PLAB, MRCP or USMLE examinations. They are based on actual questions from these examinations. You may find the Anatomy Of The Eye article more useful, or one of our many articles on Diseases & Conditions, Medical Syndromes, Health & Wellness or Home Remedies.
In this article:
Conjunctival hyperemia
MCQ: clinical scenario
MCQ: answer
MCQ: explanation

Conjunctival hyperaemia

Conjunctival hyperemia is characterized by redness of the sclera due to dilatation of the blood vessels of the eyes. Other common symptoms associated with conjunctival hyperemia include pain in the eye, blurry vision or loss of vision, increased sensitivity to light (photophobia), discharges from the eye, and systemic symptoms (swollen lymph nodes, fever, nausea and vomiting) usually encountered in acute cases (suggestive of infection).

The pattern of the eye redness may be diffuse or sectoral. Diffuse hyperemia is erythema involving the entire conjunctivae, while sectoral hyperemia refer to erythema involving only a portion, or sector, of the conjunctiva.

MCQ: clinical scenario

A 35 year old with no history of a rheumatoid disorder presents with mild photophobia and sectoral hyperemia. Topical neosynephrine is administered but the engorged vessels do not blanch.

The most likely diagnosis is:

a) orbital pseudotumor
b) uveitis
c) episcleritis
d) scleritis
e) conjunctivitis

MCQ questions & answers on medicalnotes.info

MCQ: answer

The correct answer is C

MCQ: explanation

Causes of diffuse hyperaemia include bacterial and viral conjunctivitis, blepharitis, and occasionally scleritis. Allergic conjunctivitis also causes diffuse hyperemia. Sectoral hyperaemia has episcleritis, scleritis, and pterygium as major causes. Episcleritis is an inflammatory condition of the episclera; usually sectoral and self limiting. The eye is often tender and mildly photophobic. A 2.5% neosynephrine instilled topically can be used diagnostically: the conjunctival vessels blanch but the episcleral vessels remain engorged in episcleritis as opposed to conjunctivitis where most vessels blanch.

Sectoral hyperemia, is distinguished from conjunctivitis by radially oriented vessels that do not move with the conjunctiva. Episcleritis is self-limited, although topical non-steroidal anti-inflammatory medications such as flurbiprofen or diclofenac may hasten resolution. In contradistinction to scleritis, episcleritis is not usually related to systemic rheumatoid disease.

Reference(s)
1). James P. Dunn: Ophthalmology Module. Ambulatory curriculum, The Wilmer Eye Institute, The Johns Hopkins University School of Medicine. Available online: http://legacy.hopkinsilc.org/modules/181/printer181.pdf

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