The microhook ab interno trabeculotomy procedure (µLOT) for secondary glaucoma in patients with hereditary transthyretin amyloidosis (hATTR) is safe and effective within the first year of operation, but that effects diminish after 2 years, according to a study published in the Japanese Journal of Ophthalmology. 

The ocular manifestations of hATTR include irregular pupils, vitreous opacity, amyloid angioplasty, secondary glaucoma, and needle-shaped deposits on the retinal surface. Ironically, advances in hATTR therapeutics have increased the lifespan of patients so that ocular symptoms have become particularly troublesome. 

In the specific case of glaucoma, studies have reported comparably good results from glaucoma drainage implant surgery. However, postoperative complications can occur, causing some surgeons to question its overall safety profile. µLOT, on the other hand, is a minimally invasive glaucoma surgery; studies have indicated that it is extremely safe and that it avoids conjunctiva scarring. 

The authors characterized the efficiency of this procedure in treating patients suffering from glaucoma secondary to hATTR. This retrospective study examined the results of the surgery on 18 eyes of 13 patients with hATTR. All patients had a comprehensive ophthalmological examination prior to undergoing µLOT. 

Read more about hATTR etiology 

“Our data suggest that µLOT for secondary glaucoma in hereditary transthyretin amyloidosis is safe and effective in lowering intraocular pressure for 1 year after the procedure, although the surgery’s intraocular pressure lowering effect diminishes after 2 years,” the authors concluded. 

This study explores the merits of another surgical option for surgeons to choose from when treating glaucoma secondary to hATTR. 


Kitahara J, Kakihara S, Hirano T, et al. Microhook ab interno trabeculotomy for secondary glaucoma in patients with hereditary transthyretin amyloidosisJpn J Ophthalmol. 2022;10.1007/s10384-022-00966-5. doi:10.1007/s10384-022-00966-5