Intraoperative trypan blue central landmark and its use in capsulotomy and capsulorhexis centration.

PURPOSE: To compare 3 capsulotomy centration methods. SETTING: Private clinic, Zlin, Czech Republic. DESIGN: Prospective, consecutive case series. METHODS: 180 eyes undergoing cataract surgery had anterior capsule staining with microfiltered 0.4% trypan blue solution before selective laser capsulotomy. The first 60 eyes (Group 1) had mydriatic dilated pupil centered capsulotomies. The next 60 eyes (Group 2) were centered on the trypan blue central landmark (TCL). The final 60 capsulotomies (Group 3) were centered on the patient fixated coaxial Purkinje reflex (CPR). Measurements between key anatomical landmarks and the TCL, CPR capsulotomies, and implanted intraocular lens (IOL) center were made. RESULTS: The TCL, observed in >94% of eyes in the study, coincided with the CPR with a displacement of <0.1 ± 0.1 mm. Group 1 capsulotomies were noticeably decentered on the IOLs by 0.3 ± 0.2 mm. The Group 2 symmetrical IOL relationship was maintained with a decentration of 0.15 ± 0.1 mm. Group 3 had a similar decentration with the IOLs with 0.15 ± 0.1 mm. Verification with IOLMaster 700 data and CALLISTO Eye System showed that the CPR and the TCL were coincident with the measured visual axis. CONCLUSIONS: The clearly visible TCL served as an alternate landmark to the patient fixated CPR, and being on the anterior capsule was not sensitive to tilt. Further patient compliance was not required. Both were superior to dilated pupil centration, to achieve symmetric IOL coverage. This has application for both capsulotomies and capsulorhexes.

Comparison of anterior capsulotomy techniques: continuous curvilinear capsulorhexis, femtosecond laser-assisted capsulotomy and selective laser capsulotomy.

PURPOSE: To compare the anterior capsulotomy edge tear strength created by manual continuous curvilinear capsulorhexis (CCC), femtosecond laser-assisted capsulotomy (FLACS), and selective laser capsulotomy (SLC). SETTING: Singapore National Eye Centre, Singapore and Excel-Lens, Livermore, California, USA. DESIGN: Three armed study in paired human eyes. METHODS: Capsulotomies were performed in 60 cadaver eyes of 30 donors using CCC, Victus Femtosecond Laser, (Bausch & Lomb, Rochester, New York, USA) or CAPSULaser, (Excel-Lens, Los Gatos, California, USA). Three pairwise study groups each involved 10 pairs of eyes. Study group 1: SLC eyes compared with fellow eyes with CCC. Study group 2: CCC eyes compared with fellow eyes with FLACS. Study group 3: FLACS eyes compared with fellow eyes with SLC.A shoe-tree method was used to apply load to the capsulotomy edge, and Instron tensile stress instrument measured distension and threshold load applied to initiate capsule fracture. Relative fracture strengths and distension of CCC, FLACS and SLC were determined. Scanning electron microscopy (SEM) of capsule edges were reviewed RESULTS: Anterior capsulotomies behave as non-linear elastic (elastomeric) systems when exposed to an external load. The pairwise study demonstrated that the SLC fracture strength was superior to that of CCC by a factor of 1.46-fold with SLC 277±38 mN versus CCC with 190±37 mN. Furthermore, CCC fracture strength was superior to that of FLACS by a factor of 1.28-fold with CCC 186 + 37 mN versus FLACS 145 ± 35 mN (p < 0.001). This was determined by statistical analysis utilising the Wilcoxon matched-pairs signed-ranks test and in accordance with the Consolidated Standards of Reporting Trials guidelines. The capsule edge of SLC on SEM demonstrated a rolled over edge anteriorly and an alteration of collagen. CONCLUSIONS: The strength of the capsulotomy edge for SLC was significantly stronger than that of CCC which and both were significantly stronger than FLACS. The relative strengths can be explained by SEM of each type of capsulotomy.

Efficacy and safety of a new selective laser device to create anterior capsulotomies in cataract patients.

PURPOSE: To compare the efficacy and safety of anterior capsulotomy creation with a new selective laser device (CAPSULaser) with those of manual capsulotomies. SETTING: GEMINI Eye Clinic, Zlin, Czech Republic. DESIGN: Prospective case series. METHODS: Patients were placed in cohorts based on age and cataract grade and randomly allocated to have laser capsulotomy or manual continuous curvilinear capsulorhexis (CCC). The anterior capsule was stained with microfiltered trypan blue 0.4%. The anterior capsulotomy was created with the laser device focused on the anterior capsule through a custom patient interface lens. Intraoperative video analysis with the use of an intraocular ruler and postoperative examinations were used to assess safety and efficacy (accuracy of capsulotomy size, circularity, centration). RESULTS: No intraoperative complications occurred in the laser group or the manual group. All capsulotomies in the laser group were free-floating with no tags or tears. The mean capsulotomy diameter was 5.03 mm overall (range 4.8 to 5.2 mm, laser group; 4.4 to 5.8 mm, manual group). In the laser group, all the capsulotomies were within 0.1 mm ± 0.1 (SD) of the target. The circularity accuracy was greater than 99.0% ± 1.0%; the mean centration of the capsulotomy in relation to the intraocular lens (IOL) was 0.1 ± 0.1 mm. All parameters were statistically significant (P < .01). The IOL-capsulotomy overlap was 360 degrees in all laser cases. CONCLUSIONS: Selective laser capsulotomy using a new proprietary trypan blue formulation was safe and effective in cataract surgery. The sizing, circularity, and centration of the laser capsulotomy were more accurate than those of the manual CCC, resulting in consistent 360-degree IOL coverage.

Parameters affecting anterior capsulotomy tear strength and distension.

PURPOSE: To study the effects of anterior capsulotomy diameter and discontinuity on tear threshold load and distension for the technique of continuous curvilinear capsulorhexis (CCC). SETTING: Singapore National Eye Centre, Singapore, and CapsuLaser Inc., Livermore, California, USA. DESIGN: Two separate randomized pairwise cadaver eye preclinical studies. METHODS: Capsulotomies were performed in 40 cadaver eyes of 20 donors using CCC. The pairwise comparisons were divided into 2 study groups: Study A: Continuous versus discontinuous capsulotomies; Study B: Capsulotomy diameter of 5.0 mm and smaller versus diameters of 5.2 mm and larger. A shoe-tree method was used to apply load to the capsulotomy rim, and the Instron tensile stress instrument measured threshold load and distension to initiate a capsular tear. Wilcoxon matched-pairs signed-rank tests were performed to assess statistical superiority. RESULTS: In Study Group A, all pairs demonstrated that continuous capsulotomies were better than discontinuous capsulotomies for both the anterior tear threshold load and distension (P < .01). In Study Group B, 80% of the pairs demonstrated that diameters of 5.2 mm and larger were better than those of 5.0 mm and smaller diameter (P < .05). CONCLUSIONS: Anterior capsulotomies behave as nonlinear elastic (elastomeric) systems when exposed to an external load and distension. This study demonstrated that continuous circular capsulotomies were more resistant to anterior tears than discontinuous capsulotomies. A point of irregularity or a defect in a capsulotomy rim has a high probability of being the tear initiation point. Furthermore, larger diameter capsulotomies were more resistant to anterior tears than smaller capsulotomies.

Four-dimensional breast imaging, part II: clinical implementation and validation of a computer imaging system for breast augmentation planning.

BACKGROUND: No publications exist describing the impact of three-dimensional imaging on the consultation process for breast augmentation, nor have existing software products claiming simulation features been validated. OBJECTIVES: The authors describe the application of four-dimensional technology during patient consultation to assist in planning implant size and type. METHODS: Forty-six primary breast augmentation patients underwent preoperative consultation with 4D simulation software; 35 out of 46 also received follow-up imaging. At six months postoperatively, simulated measurements were compared to actual measurements and questionnaires were mailed to patients asking them to assess the imaging experience. A follow-up phone survey 18 months postoperatively examined the persistence of patient attitudes about implant size and imaging. Practice productivity was evaluated by comparing specific parameters (such as scheduling rates) between three separate time periods for the same clinic. RESULTS: Across all parameters, breast augmentation simulations correlated highly with positive surgical outcomes (R-value = 0.68). The majority (95%) of patients believed the simulations were accurate; 89% also expressed that it enhanced trust in the surgeon and 74% reporting that it helped in choosing an implant size. Despite 48% also indicating that they would select a larger implant if they were to undergo surgery again, no patients have undergone reoperations of any kind. Compared to historical controls, scheduling rates in the practice increased from 40% to 77% after addition of simulation software. CONCLUSIONS: 4D breast imaging appears to be an accurate system for analysis, planning, simulation, and patient education for women considering primary breast augmentation, and application of this technology during the consultation process was correlated with a high degree of patient satisfaction and practice productivity.

Four-dimensional breast imaging, part I: introduction of a technology-driven, evidence-based approach to breast augmentation planning.

Although there are many three-dimensional imaging systems currently available on the market, all of them require a high degree of interaction on the part of the user, making them clinically impractical. Moreover, though claims have been made regarding the validity of these systems for imaging the breast form, there have been no previous reports validating any commercially-available implant simulation models in the plastic surgery literature. In this article, the authors describe the development and evaluate the efficacy of a novel four-dimensional (automated three-dimensional) breast imaging system, validating it as an evidence-based simulation tool for patient consultation, surgical planning, and outcomes analysis in cosmetic breast augmentation. This report, based on a series of longitudinal correlation studies with several patient cohorts, found a highly statistically significant degree of correlation and reliability between the automated measurements obtained with the four-dimensional system and manual measurements.

Incidence of breast and chest wall asymmetries: 4D photography.

BACKGROUND: Few authors have addressed preoperative soft tissue and chest wall analysis as it pertains to asymmetries that must be identified for preoperative breast augmentation planning. OBJECTIVES: The authors evaluate the incidence of breast and chest wall asymmetries. METHODS: In the present study, 125 consecutive patients underwent a voluntary dimensional analysis by a single practitioner, followed by a confirmatory 4D photographic analysis. During each patient's evaluation, the following measurements were recorded: distance from nipple to inframammary fold (IMF), base width, distance from sternal notch to nipple, horizontal areolar width, vertical areolar height, upper and lower pole pinch tests, and medial and lateral pinch tests. RESULTS: Following exclusion of patients who had undergone prior breast surgery, 117 patients were included in the final statistical analysis. Significant differences between right and left breasts were found in 81.7% of patients in one or more of the measured dimensions (p < .05). The manual measurements were confirmed with computerized 4D photography, and there was no significant difference found between the two measurement types in any objective parameter. However, there was a significant difference in the level of chest wall asymmetries identified by 4D photography. Nipple-to-IMF position asymmetry was present in 59.6% of the patients, and sternal notch-to-nipple asymmetry was present in 81.2%. Overall, 100% of the women had some degree of asymmetry (soft tissue and/or chest wall) confirmed by 4D photography. CONCLUSIONS: The 4D photography measurements in this study were consistent with objective manual measurements but provided the added benefit of identifying chest wall asymmetries more objectively. The data from this study underscore the importance of developing a systematic preoperative breast and chest wall analysis that can be individualized for each patient. The resulting asymmetries should then be discussed with the patient, along with the potential for continued or more pronounced asymmetry postoperatively.