This is a retrospective review of 319 orbital decompression operations in 169 patients (73% female) with thyroid eye disease. Three wall decompressions were performed in 92 eyes, 2-wall in 206 (medial and floor), and a single wall (medial) in 18, with respective mean reductions in proptosis of 5.4mm, 3.2mm and 3.6mm. Only nine patients had fat removal. Forty patients had strabismus prior to surgery and of these 8% were worse and 9% improved after decompression. Of those with no significant preoperative strabismus, one third developed misalignment which was usually esotropia. Twenty-one patients had serial post-decompression strabismus assessments, of which 33% improved with time but surprisingly 52% worsened. An increase in limitation of horizontal and vertical ductions of more than five degrees was seen in 54% and 38% of patients respectively. Overall, over two thirds of patients had an increase in limitation of their ductions of at least five degrees but only one third required subsequent strabismus surgery. Lower lid retraction improved in the 3-wall decompression group by about 1mm, but there was no change in upper lid retraction. Lower lid and upper lid retraction surgery was subsequently performed in 35% and 47% respectively. This is a large series with useful data. The results are interesting in that adding floor removal to a medial decompression did not increase the reduction in proptosis, but lateral wall decompression added another 2mm. In addition, upper lid retraction was unchanged by the decompression even though the lower lid retraction improved, suggesting levator fibrosis rather than proptosis as the principal cause. Although the authors suggest this might encourage simultaneous upper lid lowering and decompression surgery, they admit lid positions may change with subsequent strabismus surgery.
Postoperative changes in strabismus, ductions, exophthalmometry, and eyelid retraction after orbital decompression for thyroid orbitopathy.
Rootman DB, Golan S, Pavlovich P, Rootman J.
OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY
(Editor’s note: “A duction is an eye movement involving only one eye. There are generally six possible movements depending upon the eye’s axis of rotation: Abduction refers to the outward movement of an eye. Adduction refers to the inward movement of an eye.” Wikipedia)