[Therapeutic outcomes and influence factors of maximal orbital decompression in the treatment of severe dysthyroid optic neuropathy].

UNLABELLED:

Objective

To evaluate the effectiveness of maximal orbital decompression in treatment for severe dysthyroid optic neuropathy (DON) of thyroid associated ophthalmopathy (TAO) and predictive factors of this therapy.

Methods

The group consisted of 21 patients (30 eyes) with DON. The diagnosis was based on the following criteria: Deterioration of best corrected visual acuity (VA≤0.1), enlargement of extraocular muscles and sign of apical crowding in CT imaging, loss of colour vision.

EXCLUSION CRITERIA: VA of DON>0.1 or other diseases with visual function damage. Maximal 3-wall orbital decompression was undergone. Clinical outcomes were recorded and assessed including pre- and postoperative VA, age, clinical activity score (CAS), thyroid hormonal status and duration of DON. The pre- and postoperative VA were compared by Wlicoxon signed rank analysis. The relationships between the change of VA and age(<50 years vs ≥50 years), thyroid hormonal status(hyperthyroidism vs hypothyroidism), CAS(<3 vs ≥3), duration (<3 months vs ≥3 months), pre-VA(<0.01 vs ≥0.01) were made statistically by Mann-Whitney U-test, rank correlation analysis,and Logistic regression analysis.

Results

Thirty eyes of 21 patients (11 male, 10 female) were included in this study. Hyperthyroidism was recorded in 13 cases, the other 8 cases with hypothyroidism. The average age at the time of diagnosis was 52.9 years (range, 33.0-71.0 years). The median of the duration of DON was 4.5 months (range, 1.0-12.0 months). Twenty-eight eyes (28/30, 93%) showed improvement of visual acuity after surgery (Z=-4.62, P=0.000). There was positive correlation between pre- and postoperative VA(r=0.38, P<0.05 ). Patients with VA of 0.01 or better had better postoperative VA than those with poorer VA (0.10 vs 0.50, Z=-2.09, P=0.037). There was negative correlation between the duration and degree of improvement of postoperative VA (r=-0.44, P<0.05). Other factors such as age, thyroid hormonal status, CAS were not statistical factors for postoperative VA (Z=-1.83--0.97, P>0.05 ) and improvement of postoperative VA (Z=-1.80--0.82, P>0.05).

Conclusions

Maximal orbital decompression is safe and effective for management of visual damage in severe DON in this small sample study. Preoperative VA and duration of DON were important predictive factors for surgical outcome. Earlier diagnosis and treatment are possibly useful for improvement of prognosis of DON but large sample data are needed.(Chin J Ophthalmol, 2017, 53:416-423).