Vollman and associates investigated the effect of intraoperative floppy iris syndrome (IFIS) and found a significant difference in complication rates between groups of patients undergoing cataract surgery.
We understand that there was no standardization of preoperative and intraoperative pharmacologic measures, ophthalmic viscosurgical device use, and irrigation/aspiration technique, which makes it hard to extract meaningful indications. To accept the presented conclusions, we would appreciate if the authors could provide additional methodological details.
We noted that the authors accepted as a major limitation of the study the absence of an objective assessment of IFIS; this was based on an individual surgeon’s subjective report at the end of the procedure, and no information was provided as to whether the IFIS occurred in a mild or complete form (that is, only intraoperative iris billowing or a complete triad of signs).
The phacoemulsification platform, the incision size, the type of irrigation/aspiration devices, and the ophthalmic viscosurgical device type used in the study would need to be specified, as these factors may all affect rates of IFIS.
Moreover, the number of the involved surgeons, their experience, and whether they knew the therapeutic regimen their patients were on should also be stated. Do we understand correctly that the involved surgeons work in 5 different settings with an annual volume of cataract surgery of fewer than 400 cases/year/location?
Besides showing a 6.9% rate of posterior capsule rupture in their patients with IFIS, they also reported an alarming 3.7% and 3.1% incidence of posterior capsule rupture and anterior capsule tear, respectively, in the non-IFIS control group.
This is significantly higher than the reported evidence, showing rates of 1.9% and 0.8% for posterior and anterior capsule tears, respectively. At our institution, a training setting, these rates are 1.3% and 1.0%, respectively (unpublished data). Of note, a secondary analysis of the data collected by the Cataract National Dataset electronic multicenter audit in the United Kingdom demonstrated that complication rates were higher for cataract surgeons with a lower annual volume.
We wonder whether the authors could better characterize the 141 eyes of patients who were not on alpha-antagonist drugs and manifested IFIS: would it be possible to describe axial length and anterior chamber depth values, detail whether those eyes had undergone any intraocular surgical procedure or suffered with uveitis, and confirm that the patients had never used alpha-antagonists earlier?
We read that mechanical pupil expansion was used in 186 IFIS cases; was it employed at the start of surgery for an insufficient pupil dilation or did it become necessary during surgery owing to the manifestation of IFIS?
We also wonder whether the authors might be able to identify differences in the rate of postoperative short-term complications of phacoemulsification cataract surgery in the study vs control group, such as occurrence of cystoid macular edema, prolonged corneal edema, or prolonged intraocular inflammation.
Lastly, it does not appear clear as to why the authors labeled their study as retrospective in nature if they even performed an earlier pilot study in 2009.