Andrew Lawton, M.D.
Upper eyelid retraction in patients with thyroid –related eye disease is potentially dangerous due to corneal exposure. Patients are distressed as well by the abnormal appearance. Surgical repair is effective but not practical until the inflammatory process stabilizes. Lee, et al (Graefes Arch Clin Exp Ophthalmol 2013; epuplished Sep 2012), set out to see if subconjunctival corticosteroid injections would be effective in management of lid retraction. The authors identified 95 patients with thyroid-related eye disease and a less than six month history of eyelid retraction and/or swelling. 55 patients for a total of 75 eyes received one to three injections of 20 mg triamcinolone acetate into the subconjunctival space superficial to Mueller’s muscle at three week intervals. The remaining 40 patients representing 59 eyes received no treatment. 67% of patients treated with corticosteroids started out with severe swelling compared to 34% in the control group. 9 and 24 weeks after initiating the protocol, there was no differences in severity between the two groups. Significantly more patients receiving injections achieved clinical success at 24 weeks than in controls. The authors concluded that subconjunctival triamcinolone was effective in resolving eyelid swelling and retraction if initiate within the first six months of onset.
Another potential risk in thyroid-related orbital disease is optic nerve compression by enlarged extraocular muscles. One difficulty in management, however, is to determine the point at which surgery should be attempted to decompress the orbit. Weis, et al (Ophthalmology 2012; 119:2174-2178), reviewed CTs of 198 orbits in 99 patients with the condition and performed volumetric analysis to correlate with physical examinations. The best predictor of compressive optic neuropathy was the volume of the medial rectus muscle followed in order of significance by lateral rectus volume, superior muscle group volume, and total rectus muscle volume. Multivariate analysis indicated that medial rectus volume was the only independent predictor of compressive optic neuropathy. The authors found that simple maximum medial rectus diameter measurements could be used equally well as the full calculation of medial rectus volume. Orbital volume and distortion of the medial orbital wall did not predict optic nerve compression.
Congenital optic nerve anomalies may indicate the potential for other ocular abnormalities. Shapiro et al (Ophthalmology 2012; epublished November 2012), retrospectively identified 15 patients with congenital optic nerve anomalies. They identified 15 patients of whom 9 patients had optic nerve hypoplasia. Other diagnoses included optic nerve coloboma, morning glory syndrome, and staphyloma. All patients received examination under anesthesia with wide angle retinal photography and fluorescein angiography. The authors assessed the severity of nonperfusion of the retina with concentration on the degree of fibrovascular proliferation, vitreous hemorrhage, and tractional retinal detachment. In patients with optic nerve hypoplasia, 75% of affected eyes showed severe peripheral retinal nonperfusion. 75% had fibrovascular proliferation, 19% had vitreous hemorrhage, and 63% had tractional retinal detachment. Six eyes with severe nonperfusion required laser treatments to nonperfused retina. Of other anomalies, 88% had mild to moderated nonperfusion, 25% had fibrovascular proliferation, 12 % had vitreous hemorrhage, and 25% had tractional retinal detachment. 67% of patients with optic nerve hypoplasia and 17% with other anomalies had congenital brain abnormalities as well. The authors concluded that physicians must screen for other ocular and brain abnormalities in these patients and that laser photocoagulation may be of benefit in preventing tractional retinal detachment.
Patient X3 is a man in his 50s who has noted progressive double vision over the past six months. He described the diplopia as vertical and binocular. He reported a worsening of his symptoms if he looks down. He has no pain or discomfort although his eyes feel dry. He has lost over 100 pounds over several months; he attributed this to a painful shoulder injury that made him lose his appetite. He was referred with a presumed diagnosis of a fourth cranial nerve palsy. An MRI was read as normal; the patient brought the disc with him for my review. His medical history was otherwise unrevealing. He was taking medication for hypertension.
At exam, his visual acuity was 20/20 in each eye. He had no relative afferent pupillary defect. Confrontation testing was intact in both eyes. He demonstrated a significant decrease in depression of his right eye. He showed a 20 diopter right hypertropia in neutral position that decreased to 6 diopters in up gaze and increased to 45 diopters in down gaze. He had 1 mm of superior scleral show on his right. Hertel exophthalmometry revealed 3 mm of right proptosis. His intraocular pressure was within the normal range but 5 mmHg higher in his right eye than his left. His anterior segments appeared normal. His optic discs were pink and flat. His retinas were flat.
What are you suspecting? He had two abnormalities noted on systemic evaluation that indicated a specific diagnosis; what could they be? What would you do for your next steps?
Discussion of Case X1 from January 2013 Newsletter
Our patient has trochleitis. This has features consistent with an autoimmune process that roughly falls into the waste basket of idiopathic inflammatory orbital pseudotumor. Generally the cartilage of one trochlea becomes inflamed. The tendon of the superior oblique muscle may become inflamed as well.
Patients uniformly present with complaints of aching aggravated by moving the eye on the involved side. They may experience sudden sharp, stabbing pain as well. They will report significant tenderness on palpation of the region of the trochlea. Imaging studies and B-scan ultrasound may be of value and indicate swelling of the trochlea or the superior oblique tendon. Trochleitis is an unusual instigating factor for migraine headaches and treating the condition may result in improvement in the migraine pattern in a small number of patients.
Once the diagnosis is established mainline treatment involves non-steroidal anti-inflammatory agents such as Indomethacin and Naproxen. Patients may recover more quickly if the receive oral corticosteroids of a Kenalog injection to the region of the trochlea. The likelihood of relapse within one year is 25%. Trochleitis has been documented to be related to rheumatoid arthritis, systemic lupus erythematosus, scleritis, Brown’s syndrome and orbital myositis. A work up for these conditions may be of value in recurrent disease.