IMMEDIATE SEQUENTIAL BILATERAL CATARACT SURGERY (ISBCS) IN ADULTS WITH PREOPERATIVE DIPLOPIA

To evaluate the effects of immediate sequential bilateral cataract surgery (ISBCS) on visual parameters and binocular function in adults with diplopia and bilateral cataracts presenting to the strabismus service.

In selected patients, immediate sequential bilateral cataract surgery (ISBCS), has shown to be non-inferior in terms of efficacy, with comparable safety outcomes and superior in terms of cost effectiveness when compared with delayed sequential bilateral cataract surgery (DSBCS). 

Binocular diplopia can co-exist in patients with senile cataract. Different mechanisms explain the presence of binocular double vision in patients with cataract. This includes sensory strabismus, decompensation of phorias, paralytic strabismus and fixation switch diplopia. The advantage of ISBCS in this setting include faster visual recovery and rehabilitation, reduced postoperative anisometropia and aniseikonia, improved stereopsis and fewer postoperative visits.

Data of ISBCS cases performed at Southend University Hospital in the last 2 years (2022-2024) was collected from Theatres Logbook. Indications for bilateral surgery were collected from medical record review. This retrospective study included patients with double vision undergoing ISBCS due to bilateral cataract. Preoperative and post operative visual acuity, distance and near squint angle, fusional amplitudes, stereopsis, and convergence were evaluated. Preoperative and postoperative refraction was also analyzed when available.

28 eyes of 14 patients (71,43% female and 28,57% male) with bilateral cataract and preoperative diplopia underwent ISBCS in the last 2 years. Mean age at surgery was 71 ± 12,87. Mean follow up after surgery was 4,3 months (range 1-12). ISBCS resulted in an improvement in binocular potential in 64.28% of patients, while 30,77% of patients were free of double vision following ISBCS alone.  In all cases (100%) there was a change either in the prismatic covert test (PCT) or motility pattern following cataract surgery with impact on postoperative management. One patient with restrictive strabismus showed an increase in postoperative deviation possibly due to shift in fixation leading to a more accurate strabismus surgical planning. Postoperative complications occurred in one patient who developed unilateral cystoid macular oedema (CMO), which resolved with topical treatment.

We believe that ISBCS a safe and effective procedure in patients with preoperative diplopia and bilateral cataract and this should be the preferred procedure in these cases. This leads to faster visual rehabilitation and recovery of binocular function. Cataract surgery should be addressed before strabismus as this may have an impact on further management.

These cases should be undertaken by surgeons with an interest in strabismus or in collaboration with them.