OCT-A imaging in Grave’s orbitopathy and orbital decompression
Reviewed by Rina Bhatt

In this case series of 12 patients and 24 orbits, the authors describe the changes in the optic nerve and peripapillary blood vessel density in patients with moderate to severe Grave’s Orbitopathy (GO) undergoing orbital decompression. The patients undergoing orbital decompression for diagnoses other than GO, prior orbital surgery or other orbital pathology, and OCT-A scans with artefacts were excluded. Two wall- medial and lateral wall orbital compression was performed. However; it is unclear whether all orbits had the same decompression. All patients had a preoperative and postoperative OCT-A. The timing of postoperative OCT-A varied, and mean time was 43 days after surgery. A comparison was made between pre and postoperative vessel density measurements taken within the area overlying optic nerve and the peripapillary ring as well as eyes with dysthyroid optic neuropathy (DON) and without. Out of 24, six orbits had DON. The majority of eyes with DON showed decrease in vessel density in both the optic disc and the peripapillary areas compared to eyes without DON. This was, however, not statistically significant. The authors attribute this to a reduction in intraorbital pressure and thereby the reduction in venous pressure gradient and prelaminar venous distension from orbital decompression. The authors have acknowledged the limitations such as small sample size, variable timing of imaging post orbital decompression and the artefact error in the OCT-A scans.

Changes in peripapillary blood vessel density in Graves’ orbitopathy after orbital decompression surgery as measured by optical coherence tomography angiography.
Lewis KT, Bullock JR, Drumright RT, et al.
ORBIT
2019;38:87-94.