CHARACTERIZING COVID-19-RELATED RETINAL VASCULAR OCCLUSIONS: A Case Series and Review of the Literature

PURPOSE

To describe clinical and ophthalmologic features and outcomes of patients with coronavirus disease-19 with retinal vascular occlusions.

METHODS

Retrospective multicenter case series and PubMed review of cases reported from March 2020 to September 2021. Outcome measures are as follows: type of occlusion, treatments, best-corrected visual acuity, and central macular thickness on optical coherence tomography.

RESULTS

Thirty-nine patients were identified. Fifteen patients with a median age of 39 (30-67) years were included in the multicenter study. Vascular occlusions included central retinal vein occlusion (12 eyes), branch retinal vein occlusion (4 eyes), and central retinal artery occlusion (2 eyes). Three cases were bilateral. Baseline best-corrected visual acuity was 20/45 (no light perception-20/20). Baseline central macular thickness was 348.64 (±83) μm. Nine eyes received anti-vascular endothelial growth factor agents, dexamethasone intravitreal implant, or both. Final best-corrected visual acuity was 20/25 (no light perception-20/20), and central macular thickness was 273.7 ± 68 μm (follow-up of 19.6 ± 6 weeks). Among the 24 cases from the literature review, retinal vein occlusion was the predominant lesion. Clinical characteristics and outcomes were similar to those found in our series.

CONCLUSION

Coronavirus disease-19-associated retinal vascular occlusions tend to occur in individuals younger than 60 years. Retinal vein occlusion is the most frequent occlusive event, and outcomes are favorable in most cases.

[Reversible hypophyseal disfunction and hyperplasia in two cases of primary hypothyroidism]

BACKGROUND

Some patients with primary hypothyroidism (HP) develop massive thyrotrope cell hyperplasia determining pituitary hyperplasia with suprasellar enlargement and pituitary dysfunction. Although TRH secretion undoubtedly has some influence, the intervention of other possible factors determining this hyperplasia and dysfunction has been little assessed.

PATIENTS AND METHODS

Two patients with primary hypothyroidism with a serum TSH > 1,000 mU/I were studied. By means of CT and MR a pituitary hyperplasia was ascertained in the two patients. The pituitary functional reserve was investigated by the serum response of TSH and prolactin to the administration of TRH (400 micrograms, i.v.), bromocriptine (BRC, 5 mg, oral route), somatostatine (ST, 50 micrograms/kg/min, i.v. perfusion), and gonadotropin releasing hormone (GnRH, 100 micrograms, i.v.).

RESULTS

The TRH induced increment of TSH was 145% and 193%, respectively, compared with basal values. After the administration of BRC, TSH decreased to 57% and 84% of basal values, and PRL to 46% and 43%, respectively. TSH and PRL concentrations did not change after the administration of ST or GnRH. In both cases, hyperplasia and pituitary dysfunction returned to normality after substitutive therapy with levothyroxine.

CONCLUSIONS

Basal hyperprolactinemia and TSH and PRL responses to BRC administration suggest that central dopaminergic activity is decreased or abolished in patients with HP and pituitary hyperplasia. The massive thryrotrope cell hyperplasia and hypothyroidism itself determine pituitary dysfunction, which reverts after therapy with levothyroxine, a fact which is scarcely documented in literature.