Enophthalmos is caused weakness by: (AIIMS May 2009)
|C||Tenon’s capsule instability|
Reference : Duane’s clinical ophthalmology/Volume 2/ Chapter 48/ page no 5
Duane’s clinical ophthalmology/Volume 2/ Chapter 21/ page no 10-18
1. Enophthalmos may be caused by multiple mechanisms, the most prominent of which is loss of bony support, particularly when more than 50 % of the orbital floor is involved.
2. Disruption of the orbital fibro adipose connective tissue system (musculofibrous ligamentous system) also contributes to the formation of post traumatic enophthalmos due to displacement and change in the shape of orbital soft tissue.
3. The loss of bone and ligament support, permits posterior displacement of the globe.
4. The Tenon’s capsule is a fibrous membrane that extends from the posterior aspect of the globe to fuse anteriorly with conjunctiva, slightly posterior to the Corneo scleral junction. It is closely apposed to globe
5. The Tenon’s capsule (orbital fascia) may be divided into three parts:
a. Fascia covering the globe
b. The covering of the Extra ocular muscles
c. Check ligament extension of Extra ocular muscle fascia, that reach to the surrounding bone and the eyelids
From the above text and text given in question number 6, it is clear that, Tenons capsule instability is a major cause of the enophthalmos, as it forms all the major ligaments of the orbit , which support the globe in the orbit.