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Gorman,
Rochester, MN, USA, prospectively treated 42 euthyroid patients
with mild to moderate TED with 20 Gy to one randomly selected
orbit while the other orbit was treated 6 months later.
Measurements of thyroid function, antibody status, proptosis,
volume of extraocular muscle and fat, range of extraocular muscle
motion, eyelid fissures, and extent of diplopia were performed.
The results of this study were that no significant differences
between the treated and the untreated orbit in any parameter at 3
or 6 months were noted. No trend towards selective improvement of
the first treated orbit between 6 and 12 months were found. The
author concludes that if radiotherapy is beneficial for TED,
it’s ameliorative effects did not reach the detection level
of significance of the techniques used in this study. (Comment:
As a medical student I learned that there was an ophthalmic
syndrome called: sympathetic ophthalmitis. It was defined as
"a condition in which serious inflammation attacks the sound
eye after injury of the other". Using Medline with keywords
sympathetic and ophthalmitis I found in total 62 references on
this subject, the most recent one dating 1996. The results of
this provocative study indicate either that orbital irradiation
in TED is not of benefit or that a "reversed"
sympathetic ophthalmitis may occur. In other words, maybe the
syndrome is also true in the positive sense in that irradiation
of one orbit also has a beneficial effect on the other orbit. For
the moment I advise to continue with orbital irradiation in
indicated cases.)
Marcocci et al., Pisa, Italy, performed a randomised single blind prospective study in 82 patients with severe TED who were randomly treated either with oral glucocorticoids (Group I, 41 patients, 100 mg prednisone/day, withdrawal after 5 months) or intravenous glucocorticoids (group II, 41 patients, methylprednisolone 15 mg/kg for 4 cycles and then 7.5 mg/kg for 4 cycles, cycles were on alternate days at 2-week intervals). Both patient groups received orbital irradiation. No difference between the groups were present with regard to age, gender, duration of hyperthyroidism, or TED, prevalence of smokers, and thyroid volume. Clinical activity score (CAS) decreased in group I from 4.2 to 2.2 and in group II from 4.5 to 1.7. Group I vs II p = 0.03. Decrease in proptosis 23.0 to 21.7 and 23.2 to 21.6 (I vs II, NS), diplopia 33 to 27 and 23 to 14 (I vs II, NS). Overall responders 26/41 vs 36/41 (I vs II p=0.019). The authors conclude that IV high dose glucocorticoids is more effective than oral high dose glucocorticoids. Side effects were not different in both groups except that Cushingoid features were more prevalent when glucocorticoids were orally administered. Gerding et al., Amsterdam, The Netherlands, evaluated whether TSH receptor (TSHR) antibodies are related to activity and severity of TED. TSHR antibodies were measured as TBII and TSH stimulating immunoglobulins (TSI) using cAMP response of a TSHR transfected cell line in 63 patients (30 females, mean age 53,0 years) with untreated moderately severe TED. All patients were euthyroid for >2 months. TBII and TSI levels were strongly positively correlated (r=0.67) and each was also correlated with clinical activity score (CAS), TBII r = 0.54, TSI r = 0.50. Furthermore, a significant relation was present between TBII (r = 0.36) and TSI (r = 0.49) and proptosis. The authors conclude that TSHR antibody levels correlate both with severity of TED and also strongly with CAS supporting the hypothesis of the pathogenic role of TSHR antibodies in the pathogenesis of TED. This fact is in agreement with the presence of TSHR antigens in the orbit. (Comment: This is another study producing evidence that the TSHR plays a central role in the pathogenesis of TED.) Wakelkamp et al., Amsterdam, The Netherlands, measured the following cytokines: IL-IRA, sIL-2R, IL-6, sIL-6R, TNF alpha-I, and TNF alpha-II in 62 patients with (untreated, moderately severe) TED who were euthyroid on antithyroid drugs. Results were compared with those from 62 matched healthy controls. Except for IL-IRA all other cytokines were elevated in TED patients. Elevated concentrations were not related to thyroid function or the presence of thyroid autoantibodies. With regard to the question if cytokines could predict response of active TED to radiotherapy, only IL-6 were higher in responders than in non-responders. |
