Skip to content Skip to navigation

Connexions

You are here: Home » Content » Images of Memorable Cases: Case 26

Navigation

Lenses

What is a lens?

Definition of a lens

Lenses

A lens is a custom view of Connexions content. You can think of it as a fancy kind of list that will let you see Connexions through the eyes of organizations and people you trust.

What is in a lens?

Lens makers point to Connexions materials (modules and collections), creating a guide that includes their own comments and descriptive tags about the content.

Who can create a lens?

Any individual Connexions member, a community, or a respected organization.

What are tags? tag icon

Tags are descriptors added by lens makers to help label content, attaching a vocabulary that is meaningful in the context of the lens.

This content is ...

Affiliated with (What does "Affiliated with" mean?)

This content is either by members of the organizations listed or about topics related to the organizations listed. Click each link to see a list of all content affiliated with the organization.
  • Ricepress display tagshide tags

    This module is included inLens: Rice University Press Titles
    By: Rice University PressAs a part of collection:"Images of Memorable Cases: 50 Years at the Bedside"

    Click the "Ricepress" link to see all content affiliated with them.

    Click the tag icon tag icon to display tags associated with this content.

Recently Viewed

This feature requires Javascript to be enabled.

Tags

(What is a tag?)

These tags come from the endorsement, affiliation, and other lenses that include this content.

Images of Memorable Cases: Case 26

Module by: Herbert L. Fred, MD, Hendrik A. van Dijk. E-mail the authors

User rating (How does the rating system work?)
Ratings

Ratings allow you to judge the quality of modules. If other users have ranked the module then its average rating is displayed below. Ratings are calculated on a scale from one star (Poor) to five stars (Excellent).

How to rate a module

Hover over the star that corresponds to the rating you wish to assign. Click on the star to add your rating. Your rating should be based on the quality of the content. You must have an account and be logged in to rate content.

:
(0 ratings)
http://rup.rice.edu/memcases-button.jpg

Case_26-pres1-1.jpg

Normal conjunctival circulation (approximately x35).

Case_26-pres1-2.jpg

Conjunctiva of a profoundly anemic teenager (approximately x30).

Inspection of the conjunctiva with the +40 lens of the ordinary ophthalmoscope can be a useful adjunct to the diagnosis of certain types of sickle cell disease, particularly the homozygous form. The characteristic sign consists of sharply defined, dark-red, comma-shaped or corkscrew-shaped vessel fragments that appear isolated from the rest of the conjunctival circulation. These anomalous segments are visible primarily in that part of the lower bulbar conjunctiva covered by the lid.

The pathogenesis of this conjunctival sign remains speculative. There is evidence, however, that endothelial proliferation with trapping of erythrocytes occurs in the distal portion of some capillaries; immediately proximal to such involvement, the vessels are dilated and thin- walled. Infusion of blood or inhalation of oxygen can modify, if not temporarily eliminate, the sign. Conversely, eye drops that contain vasoconstricting agents can render the sign more conspicuous.

Content actions

Give Feedback:

E-mail the module authors | Rate module ( How does the rating system work?)

Rating system

Ratings

Ratings allow you to judge the quality of modules. If other users have ranked the module then its average rating is displayed below. Ratings are calculated on a scale from one star (Poor) to five stars (Excellent).

How to rate a module

Hover over the star that corresponds to the rating you wish to assign. Click on the star to add your rating. Your rating should be based on the quality of the content. You must have an account and be logged in to rate content.

(0 ratings)

Download:

Module PDF

Add module to:

My Favorites (?)

'My Favorites' is a special kind of lens which you can use to bookmark modules and collections directly in Connexions. 'My Favorites' can only be seen by you, and collections saved in 'My Favorites' can remember the last module you were on. You need a Connexions account to use 'My Favorites'.

| A lens (?)

Definition of a lens

Lenses

A lens is a custom view of Connexions content. You can think of it as a fancy kind of list that will let you see Connexions through the eyes of organizations and people you trust.

What is in a lens?

Lens makers point to Connexions materials (modules and collections), creating a guide that includes their own comments and descriptive tags about the content.

Who can create a lens?

Any individual Connexions member, a community, or a respected organization.

What are tags? tag icon

Tags are descriptors added by lens makers to help label content, attaching a vocabulary that is meaningful in the context of the lens.

| External bookmarks