During phacoemulsification, shallow anterior chamber is encountered. What are the possible factors?

Answer
This may be caused by low intraocular pressure such as:
a. poor infusion (kink in line, tight line, bottle low, bottle empty)
b. leakage of wound
or high intraocular pressure such as:
a. choroidal haemorrhage
b. irrigation entering posterior chamber
c. excessive periorbital or retrobulbar anaesthesia
d. patient breath holding
e. speculum pressing on the globe
 

During phacoemulsification, there is a deepening of the anterior chamber. What are the possible factors?

Answer
Possible factors include:
a. globe perforation during administration of anaesthesia
b. lack of vitreous support such as myopia or post-vitrectomy
c. aspiration blocked
d. zonule dehiscence or posterior capsule rupture
e. bottle too high
 

What would you do if posterior capsule rupture occurs during phacoemulsification?

Answer
a. stop the operation and investigate to see if there is vitreous 
entering the anterior chamber and any dropped nucleus
b. tamponade the rupture with viscoelastic
c. convert the operation if the nucleus has not been cracked
or all four pieces are left.
d. if small pieces left perform vitrectomy first and remove the 
lens with either the vitrectomy tip or phaco. If there is sufficient 
capsular support, place the lens in the sulcus (the lens power
needs to be reduced by 0.50 D). Otherwise use an anterior
chamber lens implant.
e. if there is dropped nucleus, avoid chasing the nucleus into
the vitreal cavity with the vitrectomy tip as there is an increased
risk of retinal detachment. Clear the vitreous, close the wound 
and ask for vitreoretinal surgeon's assistance.