Comparative quantification of ingress of trypan blue into the anterior chamber after microcoaxial, standard coaxial, and bimanual phacoemulsification

Grooved and nongrooved clear corneal incisions in phacoemulsification: permeability study

PURPOSE

To detect the inflow of trypan blue through grooved and nongrooved sutureless self-sealing clear corneal incisions at the end of phacoemulsification as compared to a control group.

METHODS

A prospective randomized masked trial considered 52 eyes randomized into 3 groups in which phacoemulsification was performed: group A, nongrooved incisions; group B, grooved incisions; and group C, controls. By the end of each surgery, trypan blue was instilled on the ocular surface in groups A and B and rinsed out after 2 minutes. A sample of the anterior chamber content was collected and analyzed by high-performance liquid chromatography to identify and quantify the trypan blue concentration. The presence of trypan blue was expressed as a specific single peak graphic image. The mean areas of these peaks were used to assess the groups using a nonparametric Mann-Whitney test.

RESULTS

There was a statistically significant difference between the nongrooved incisions group and the control group (p = 0.0448). No significant difference was observed between group B (grooved incision) and controls (p = 0.1800).

CONCLUSIONS

Trypan blue was detected in the anterior chamber when nongrooved clear corneal incision was used. There was no trypan blue detection in the group with grooved clear corneal main incisions.

Study of fluid ingress through clear corneal incisions following phacoemulsification with or without the use of a hydrogel ocular bandage: a prospective comparative randomised study

PURPOSE

To assess the use of a hydrogel ocular bandage (HOB) on clear corneal incisions in phacoemulsification cataract surgery and determine whether HOB reduces ocular surface contaminants ingress after routine surgery.

METHODS

In this prospective randomized controlled study, thirty eyes of patients undergoing uneventful phacoemulsification were recruited consecutively and randomly assigned to have a HOB applied to the corneal incision at the end of the surgery or not. At the end of the surgery, trypan blue (TRB) was instilled on the ocular surface, aqueous fluid was aspirated from the anterior chamber (AC) and its optical density was measured using ultraviolet spectrophotometry. The corneal incisions were examined postoperatively using anterior segment optical coherence tomography. Main outcome measures were concentration of TRB in the AC, corneal incision architecture, intraocular pressure (IOP) and Seidel test.

RESULTS

All incisions were Seidel negative. The mean IOP in the immediate postoperative period was 18.1 ± 5.48 mmHg for the intervention group and 16.9 ± 5.7 mmHg for the control group (p > 0.05). No architectural differences of the incisions between the two groups were noted. The total mean length of the three-step corneal incisions in the two groups was 2261.2 ± 96.92 μm and 2263 ± 119.75 μm, respectively (p > 0.05). No trace of TRB was detected in any of the samples.

CONCLUSION

Proper surgical wound construction without the use of a HOB is efficient in preventing the ingress of fluid through the main corneal incision postoperatively.

OCT-documented incision features and natural history of clear corneal incisions used for bimanual microincision cataract surgery

PURPOSE

Use of anterior segment OCT to identify features and natural history of bimanual incisions used only for phacoemulsification and a main incision used only for intraocular lens insertion.

METHODS

Prospective study of 25 subjects who had uncomplicated bimanual phacoemulsification. The Zeiss Visante OCT identified incisions at 1 day, 1 week, and 1 month postoperatively. The absence or presence of features, endothelial gaping, detachment of the Descemet membrane, endothelial misalignment, epithelial gaping, and/or loss of coaptation, was recorded. Main incision data were compared with bimanual incision data. The difference for each feature, between the main incision and the bimanual incision, at each time point and over time were calculated.

RESULTS

The most common findings at 1 day, 1 week, and 1 month were main incision endothelial misalignment (52%) and bimanual incision endothelial gape (24%), main incision endothelial misalignment (60%) and bimanual incision endothelial gape (22%), and main incision endothelial misalignment (35%) and bimanual incision endothelial misalignment (14%), respectively. Only at 1 day and 1 week was endothelial misalignment significantly more common in the main incision (P = 0.0352 and 0.0005, respectively). The only other incision feature that differed significantly was endothelial gape, which was more frequent in the bimanual incision at 1 week (P = 0.0391). For each incision feature combined over all time periods, only endothelial misalignment was significantly more prevalent in the main incision (P = 0.0004), whereas endothelial gape was more common in the bimanual incision (P = 0.0352).

CONCLUSIONS

Using OCT, bimanual phacoemulsification did not adversely affect the anatomic incision integrity and healing.

Early changes in corneal edema following torsional phacoemulsification using anterior segment optical coherence tomography and Scheimpflug photography

PURPOSE

To assess corneal edema after torsional phacoemulsification using anterior segment optical coherence tomography (AS-OCT) and Scheimpflug photography (Pentacam).

METHODS

Seventy-six eyes with cataract surgery were randomized into 2 groups: a 2.2 mm micro-coaxial incision group (n = 37) and a 2.8 mm standard incision group (n = 39). Patients were examined preoperatively and at 1 day, 1 week and 1 month postoperatively. Incision architecture and pachymetry at the wound level were measured by AS-OCT. The corneal volume within 3.0 and 10.0 mm circles of the cornea was measured using Pentacam.

RESULTS

The cumulative dissipated energy (CDE) was lower in the micro-coaxial incision (2.2 mm) group than in the standard incision (2.8 mm) group (P = 0.043). Corneal edema measurements showed less corneal thickness at the endothelial side of the incision on postoperative day 1 in the micro-incision group (1061 ± 76 vs. 1153 ± 97 μm, P = 0.041). The corneal volume within the 10.0 mm circle was less on postoperative day 1 in the micro-incision group (63.75 ± 4.83 vs. 65.97 ± 4.52 mm(3), P = 0.035). The endothelial cell count did not change significantly throughout the study.

CONCLUSION

The micro-coaxial 2.2 mm incision may incur slightly less damage than the 2.8 mm standard incision in the context of torsional phacoemulsification. Observation of corneal morphology and damage using AS-OCT and Pentacam can be helpful in the evaluation and quantification of fine corneal edema.

Coaxial, microcoaxial, and biaxial microincision cataract surgery: prospective comparative study

PURPOSE

To compare the intraoperative and postoperative results of 3 phacoemulsification techniques.

SETTING

Atatürk Training and Research Hospital, 2nd Ophthalmology Department, Ankara, Turkey.

METHODS

In this prospective randomized study, patients had standard coaxial (2.8 mm incisions), microcoaxial (2.2 mm incisions), or biaxial microincision (1.2 to 1.4 mm trapezoidal incisions) phacoemulsification. Intraoperative phaco parameters and total surgical time were measured and complications recorded. Postoperative visual acuity improvement, pachymetric differences, and surgically induced astigmatism (SIA) results were compared.

RESULTS

Each group comprised 45 eyes. There were no significant differences between the 3 groups in demographic, morphologic, or preoperative surgical data. The mean effective phaco time was 2.56 seconds +/- 2.46 (SD) in the standard coaxial group, 1.98 +/- 1.91 seconds in the microcoaxial group, and 1.29 +/- 1.85 seconds in the biaxial microincision group (P<.05). The mean total surgical time was 14.48 +/- 4.21 minutes, 13.01 +/- 3.66 minutes, and 18.79 +/- 6.58 minutes, respectively (P<.01), and the mean measured final incision size was 2.83 +/- 0.11 mm, 2.26 +/- 0.07 mm, and 1.89 +/- 0.21 mm, respectively. The mean SIA 90 days postoperatively was 0.46 diopter (D), 0.24 D, and 0.13 D, respectively (P<.01). There was no statistically significant difference in the complication rate, visual acuity gain, or pachymetric change between the groups (P>.05).

CONCLUSIONS

All 3 techniques were reliable, functional, and effective, yielding good visual outcomes and low phaco parameters and complication rates. Biaxial microincision surgery, with the smallest incisions, induced less astigmatism and reduced all intraoperative phaco parameters except total surgical time.

Incision sizes at different stages of phacoemulsification with foldable intraocular lens implantation

PURPOSE

To evaluate incision sizes during different stages of phacoemulsification and after implantation of a foldable acrylic intraocular lens (IOL).

SETTING

Private eye center, Manila, Philippines.

METHODS

In this prospective observational case series, incision widths were measured before and after microcoaxial phacoemulsification (2.2 mm), after cortical removal, and after implantation of a 6.0 mm optic, foldable, single-piece aspheric hydrophobic acrylic IOL using a D cartridge and a Monarch III injector.

RESULTS

The incision width increased in 101 (93.5%) of the 108 eyes; the enlargement was 0.1 mm in 78 eyes (77.2%) and 0.2 mm in 23 eyes (22.8%). The final incision width was 2.3 mm in 78 eyes (72.2%), 2.2 mm in 27 eyes (25.0%), 2.1 mm in 2 eyes, and 2.4 mm in 1 eye. Enlargement occurred during phacoemulsification in 39 eyes, during cortical removal in 33 eyes, and during IOL implantation in 52 eyes; 23 eyes had more than 1 enlargement. Before IOL implantation, the incision was smaller than 2.2 mm in 76 eyes (70.4%); after IOL implantation, the incision increased to 2.3 mm in 47 eyes (61.8%). Thirty-two eyes (29.6%) had a 2.3 mm incision before IOL implantation; the incision increased further (by 0.1 mm) after IOL implantation in 1 eye.

CONCLUSIONS

Incision enlargement occurred at different stages of phacoemulsification, mostly during IOL implantation. More than 72% of eyes had a final incision of 2.3 mm. Beginning with a 2.3 mm incision may prevent wound tears and surface irregularities.

Bimanual microincisional cataract surgery technique and clinical outcome

Bimanual microincisional cataract surgery has been introduced recently as a technique for cataract surgery and it is gaining interest of many cataract surgeons in the world. Over the last few years many changes were made in the phacoemulsification machines and the intraocular lenses design which allowed bimanual microincisional cataract surgery to be safer and more efficient. The purpose of this review is to introduce the technique of bimanual microincisional cataract surgery and to review all the prospective randomized studies comparing bimanual microincisional cataract surgery and standard phacoemulsification in term of safety and efficacy parameters.