Suprachoroidal haemorrhage during vitrectomy
Suprachoridal hemorrhage occurs in pre-disposed individuals .under some precipitating surgical environs during vitrectomy.
predisposed individuals include
1) elderly patients- brittle vessels
2) high myopic patients- low scleral regiditiy
3) hypertensive/ those on anti-platelet/anticouaglants
surgical environs that precipiate an suprachoroidal hemorrhage
i have mainly encountered it during or after air fluid exchange..
a) when the fluid is stopped but air does not enter due to some kinking or if the 3 way has not been turned on correctlythis can lead to globe collapse
b).when you remove your instruments there is a sudden pressure gradient created especially if you keep your pressure high to flatten the retina .and you have a non valved cannula reducing the air pressure b/w 20-25 would reduce this pressure gradient between the inside and outside and a valved cannula is helpful..
c) using a high active suction to remove the fluid can sometimes cause globe collapse..if there is a mismatch between air pressure and suction.( i have observed that suction in different machines is different for the same set levels)
d) another important time is when tightening the bandafter Fluid air exchange is a dangerous time i have encountered it at least 2 times..one was a massive other was a limited.now i tighten the band under fluid or after injecting oilbut tightening after putting oil makes it messy.i have also started doing laser after oil injection..in this way multiple instrument entry under air is eliminated (in rheg RDs/ TRDs)classically i had been trained to do laser under air..but doing under oil is simpler/easier /safer in my limited experience.