Cataract surgery using the bimanual phacoemulsification technique with an Accurus system and Mackool microphaco tip

Comparison of the IOLMaster 700 and the Pentacam in the Analysis of the Lens Nuclear Density Before the Cataract Surgery

Purpose: To evaluate the difference of the lens nuclear density measured before and after mydriasis by using the IOLMaster 700 (Carl Zeiss Meditec AG, Jena, Germany) and the Pentacam Scheimpflug imaging (Pentacam HR, Oculus Incorporation, Wetzlar, Germany) and investigate the relationship between the measurement data and the phacoemulsification parameters.

Methods: Patients with age-related nuclear cataracts diagnosed on the slit-lamp examination were enrolled in the age range of 53–76 years. No patient had a history of ocular surgery, laser treatment, or general disorders affecting vision. The mean optical density (OD) was measured by the IOLMaster 700 by using the Image-Pro^® Plus software before and after mydriasis. The Pentacam nucleus densitometry (PND) was obtained automatically from the Pentacam Scheimpflug imaging and compared with OD. The correlation between OD and effective phacoemulsification time (EPT), PND, and EPT were analyzed, respectively.

Results: In this study, 53 eyes of 52 patients were evaluated. Before and after mydriasis, the mean OD values were 64.34 ± 23.31 and 63.81 ± 23.21 pixel units, respectively; the mean PND values were 28.51 ± 11.42 and 25.41 ± 11.31, respectively; and the mean EPT value was 6.24 ± 3.49. The Bland–Altman analysis showed that the lens nuclear densities of the two devices were highly consistent. There was no significant difference in the OD values (t = 0.455, p > 0.05) before and after mydriasis, but the difference has existed in the PND values (t = 2.509, p < 0.05). The OD and PND values were positively correlated with EPT before and after mydriasis (r_OD−Before = 0.604, r_OD−After = 0.593, r_PND−Before = 0.701, and r_PND−After = 0.891, p < 0.01).

Conclusion: The combination of the IOLMaster 700 and the Image-Pro^® Plus software can quantitatively evaluate the degree of the cataract lens opacification. It has good consistency with the Pentacam and is positively correlated with the phacoemulsification parameters. It is expected to become a new method to predict the phacoemulsification parameters before and during cataract surgery.

Comparative outcomes of bimanual MICS and 2.2-mm coaxial phacoemulsification assisted by femtosecond technology

PURPOSE

To compare the efficacy and safety outcomes of bimanual microincision cataract surgery (MICS) versus 2.2-mm coaxial phacoemulsification assisted by Femtosecond LenSx (Alcon-LenSx Inc., Aliso Viejo, CA).

METHODS

This prospective, randomized, observational, comparative case series comprised 50 cataractous eyes of 50 patients receiving femtosecond laser refractive lens surgery followed by a bimanual MICS technique with two 1-mm incisions (25 patients) (FemtoMICS group) and a coaxial phacoemulsification technique with a 1-mm paracentesis and a 2.2-mm principal incision (25 patients) (FemtoCoaxial group). The main outcomes measures were: ultrasound power, effective phacoemulsification time, postoperative spherical equivalent, higher-order aberrations (corneal and internal), corneal thickness, endothelial cell count, macular thickness, and complications during and after surgery. Both groups were absolutely comparable for all variables preoperatively.

RESULTS

Mean ultrasound power was 1.8% ± 0.9% for MICS and 14.7% ± 4.9% for 2.2-mm incisions (P < .001). Effective phacoemulsification time values for MICS and 2.2-mm incisions were 1.5 ± 0.9 and 4.5 ± 2.9 sec, respectively (P = .002). Mean postoperative spherical equivalent was −0.26 for FemtoMICS and −0.33 for FemtoCoaxial (P > .05). The efficacy index at 1 month postoperatively was 160.2% for FemtoMICS and 149% for FemtoCoaxial. No significant differences were found in corneal thickness, endothelial cell count, and macular thickness. Complications included posterior capsule rupture (4%) and anterior capsule rupture with no posterior capsule tear (4%) for FemtoMICS and bridges due to incomplete capsulorhexis (4%) for FemtoCoaxial.

CONCLUSIONS

MICS and coaxial phacoemulsification techniques assisted by the Femtosecond LenSx achieved excellent safety and efficient outcomes. The FemtoMICS technique was surgically and statistically more efficient than the FemtoCoaxial technique.

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.

Effect of gauge thickness on wound-width measurements in microincision cataract surgery

PURPOSE

To evaluate the effect of gauge thickness on wound-width measurement values in microincision cataract surgery (MICS).

SETTING

Kosei Chuo Hospital, Tokyo, Japan.

METHODS

For intraocular lens (IOL) implantation, the incision was enlarged with 1 of 2 knives of different widths. Before and after IOL insertion, the wound width was measured with a 0.15 mm thick gauge (F-gauge), which was the same thickness as both types of knife, and a commercially available 0.35 mm thick gauge (A-gauge).

RESULTS

In the 2.2 mm incision group, the mean wound width before IOL insertion was 2.20 mm+/-0.03 (SD) measured with the F-gauge and 2.16+/-0.05 mm measured with the A-gauge; the difference was statistically significant (P=.002). The mean wound width after IOL insertion was 2.41+/-0.08 mm using the F-gauge and 2.35+/-0.09 mm using the A-gauge; the difference was statistically significant (P<.0001). In the 2.4 mm incision group, the mean wound width before IOL insertion was 2.39+/-0.04 mm using the F-gauge and 2.31+/-0.06 mm using the A-gauge (P<.0001); the mean wound width after IOL insertion was greater than 2.5 mm in both groups.

CONCLUSIONS

In MICS, when the wound-width gauge thickness exceeded the knife thickness, the potential for measurement errors increased. Thus, a similar thickness between the 2 instruments may be preferable.