Rotational stability and capsular bag performance of a hydrophobic acrylic open-loop single-piece intraocular lens.

PURPOSE: To evaluate the rotational stability and capsular bag performance of a blue light-absorbing hydrophobic acrylic open-loop single-piece intraocular lens (IOL) with a blast-finished anchor wing haptic design during the first 6 postoperative months. METHODS: In this prospective clinical study, patients with age-related cataract and potential postoperative corrected distance visual acuity (CDVA) of 0.2 logMAR or better were included. The patients received a non-toric hydrophobic acrylic single-piece IOL with an axis mark (YST0.00; Nidek Co. Ltd, Japan). Surgeries were video-taped. Retroillumination images were acquired 1 h, 1 week and 6 months postoperatively. Rotational stability was assessed by precise image overlay. At 6 months, Purkinje meter measurements were performed to evaluate tilt and decentration. RESULTS: In total, 100 eyes of 77 patients were included in the analysis. Mean absolute rotation was 2.1 ± 1.7° (median 1.7, range: 0-7.9) at 6 months (1 h - 6 months postoperatively). IOL rotation was ≤3° and ≤6° in 74 (74%) and 98 (98%) eyes, respectively. Mean absolute IOL rotation from the end of surgery to 6 months was 2.5 ± 2.2° (median 2.3, range: 0-15.6; n = 78). Mean tilt (pupillary axis) and decentration were 4.1 ± 1.9° (median 4.0, range: 0.5-8.2) and 0.35 ± 0.17 mm (median 0.32, range: 0.06-0.91) respectively (n = 84). Postoperatively, 98 (98%) eyes achieved a CDVA of 0.2 logMAR or better, 95 (95%) of ≤0.1 and 81 (81%) of ≤0.0. CONCLUSIONS: This hydrophobic acrylic single-piece IOL showed an excellent rotational stability and capsular bag position with low tilt and decentration values.

Assessing the astigmatism-reducing effect of toric intraocular lenses in eyes with low astigmatism: randomized masked bilateral comparison.

PURPOSE: To evaluate the astigmatism-reducing effect of toric intraocular lenses (IOLs) for low amounts of corneal astigmatism. SETTING: Hanusch Hospital, Vienna, Austria. DESIGN: Randomized, masked, controlled trial with bilateral comparison. METHODS: Patients scheduled for bilateral cataract surgery and a corneal astigmatism in both eyes between 0.75 diopters (D) and 1.5 D were included in this study. The first eye was randomized to receive either a toric IOL or a nontoric IOL, and the contralateral eye received the other type of IOL. At the follow-up visits, optical biometry, corneal measurements with tomography and topography, autorefraction, subjective refraction, corrected and uncorrected distance visual acuity (CDVA/UDVA) with ETDRS charts and a questionnaire were performed. RESULTS: 58 eyes were included in the study. Postoperative median UDVA was 0.00 (logMAR) in the toric eyes and 0.10 in the nontoric eyes ( P = .03). The median CDVA was 0.00 in both groups ( P = .60). Median residual astigmatism determined by subjective refraction and autorefraction in the toric eyes was 0.25 D and 0.50 D, respectively ( P = .04), and 0.50 D and 1.00 D in the nontoric eyes, respectively ( P < .001). CONCLUSIONS: The use of a toric IOL appears to be appropriate from a threshold value of approximately 0.75 D preoperative corneal astigmatism. Further studies in a larger patient population are needed to confirm these results.

Rotational stability of a new toric intraocular lens with an advanced optical profile.

PURPOSE: To examine the rotational stability of a new toric intraocular lens (IOL), the TECNIS Eyhance Toric II, over a course of 3 months. SETTING: Vienna Institute for Research in Ocular Surgery, Hanusch Hospital, Vienna, Austria. DESIGN: Prospective unmasked single-center study. METHODS: 50 eyes of 50 patients with cataract and regular corneal astigmatism ≥0.75 diopters (D) were included. The TECNIS Eyhance Toric II IOL was implanted in 1 eye of each study patient. Images of the alignment axis of the IOL were taken intraoperatively, as well as at 1 hour, 1 week, and 3 months postoperatively. For the measurement of toric IOL rotation, images were superimposed on the basis of ocular landmarks. Uncorrected and corrected distance (4 m) and intermediate (66 cm) visual acuities were assessed at the 3-month visit. RESULTS: There was no significant difference in the rotational position between the intraoperative and 3 month timepoints, with a mean rotation of 1.34 ± 1.46 degrees, in 27 examined eyes. ( P = 0.313). No patients had to undergo repositioning of the toric IOL. A significant reduction of refractive cylinder occurred from preoperatively 1.8 ± 1.1 to 0.40 ± 0.42 D at the 3-month visit ( P = .001; n = 43). The corrected distance visual acuity improved significantly from 0.28 ± 0.16 logMAR preoperatively to -0.01 ± 0.13 logMAR at 3 months postoperatively ( P = .001; n = 43). CONCLUSIONS: The TECNIS Eyhance Toric II showed a good visual performance with no significant rotation over a course of 3 months and, therefore, an excellent rotational stability. The intraocular lens showed a good safety profile with no adverse events.

Effect of Air Tamponade among Patients with Epiretinal Membranes and Intraretinal Cystoid Changes Undergoing Vitrectomy with Membrane Peeling - A Prospective Randomized Trial. / Effekt der Lufttamponade bei Patienten mit epiretinalen Membranen und intraretinalen zystoiden Veränderungen nach Vitrektomie mit Membrane Peeling ­ eine prospektive randomisierte Studie.

BACKGROUND: The effect of air tamponade among patients undergoing vitrectomy with membrane peeling for removal of epiretinal membranes (ERM) is controversially discussed. The aim of the present study was to analyze differences in outcomes between air tamponade and balanced salt solution (BSS) in a study population with preoperative intraretinal cystoid changes. PATIENTS AND METHODS: This randomized study included patients scheduled for pars plana vitrectomy with membrane peeling owing to ERM and intraretinal cystoid changes. Air tamponade or BSS at the end of surgery was applied according to preoperative randomization. Optical coherence tomography and best-corrected distance visual acuity (DCVA) measurements were performed before surgery, 5 days after surgery, and 3 months after surgery. RESULTS: From 96 patients included, 85 eyes had full follow-up and could be included for analysis. Median improvement of DCVA was + 16 EDTRS letters (IQR: 8 to 22) among patients with BSS, while it was + 13 EDTRS letters (IQR: 8 to 17) among patients with air tamponade. There was a trend for better improvement of DCVA when BSS was left at the end of surgery, compared to air tamponade, but not reaching statistical significance. CONCLUSIONS: There were no statistically significant differences concerning resorption of preoperative intraretinal cystoid changes, improvement of visual acuity, and final DVCA between air tamponade and BSS.

An evaluation of the efficacy of a supplemental computer-based tutorial to enhance the informed consent process for cataract surgery: an exploratory randomized clinical study.

BACKGROUND: To assess whether informing patients with a computer-based tutorial in addition to standard informed consent influences the patient's attitude towards surgery and increases patient's knowledge. METHODS: In this prospective, exploratory, randomized clinical study, patients scheduled for their first eye cataract surgery were randomly allocated to two groups, receiving standard face-to-face informed consent (control group) or additionally using an interactive computer-based tool (CatInfo) containing an audiovisual presentation about cataract and its treatment (study group). Cataract-related knowledge and decisional confidence (decisional conflict scale (DCS)) were assessed as well as one-month postoperatively decisional regret (decision regret scale (DRS)) and willingness to exchange face-to-face discussion time for the use of such a tool. RESULTS: The study comprised 134 patients, 64 patients in the study group and 70 in the control group. Patients in the study group answered more questions correctly, 16.3 ± 2.0 (median 16.5, 11.0-19.0) versus 15.5 ± 1.9 (median 16.0, 8.0-19.0; p = 0.01). Patients showed a high decisional confidence with a study group mean DCS score of 92.4 ± 9.8 (median 96.9, 65.6-100) and control group score of 91.6 ± 10.9 (median 95.3, 43.3-100; p = 0.52). Mean DRS score in the study group was 2.5 ± 8.0 (median 0, 0-40) and 4.3 ± 12.5 (median 0, 0-75) in the control group (p = 0.14). Of study group patients 23 (67.6%) were willing to trade time, on average 158 ± 180 s (median 120 s, 45-900). Satisfaction with the tool was high with a mean of 9.1 ± 1.3 out of 10 (median 9.7, 5.0-10). CONCLUSIONS: Cataract-related knowledge was generally good, with slightly higher scores in the study group. In both groups, decisional confidence was high and regret after surgery was low. A tendency towards slightly higher decisional confidence and lower regret was found in the study group, although these differences were not statistically significant. Additional use of an interactive computer-based tool may prove useful in the informed consent process in a high-volume cataract outpatient setting. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04975126. Retrospectively registered - July 23, 2021.

Evaluation of intraoperative aphakic eye axial length measurements using swept-source OCT.

PURPOSE: To evaluate intraoperative aphakic eye axial length (AL) measurements using swept-source optical coherence tomography (SS-OCT). SETTING: Hanusch Hospital, Vienna, Austria. DESIGN: Prospective single-center study. METHODS: Patients scheduled for cataract surgery were measured using SS-OCT (IOLMaster 700, Carl Zeiss Meditec AG) to assess the AL. Intraoperatively (intra-OP), SS-OCT measurements were performed with a prototype device (IOLMaster 700 connected to an OPMI Lumera 700 microscope, CZM) at the beginning of cataract surgery furthermore of the aphakic eye and 2 months after surgery. RESULTS: 106 patients were included. Of the 59 eyes of 59 patients, the phakic median AL preoperatively and intra-OP was 23.61 mm ± 0.96 (standard deviation [SD]) and 23.51 mm ± 0.96 (SD), respectively. The absolute median difference was 0.028 ± 0.02 (SD) (P = .049). Median phakic AL intra-OP vs 2 months postoperatively (post-OP) was 23.51 mm ± 0.97 (SD) vs 23.49 mm ± 0.95 (SD). The absolute median difference was 0.049 ± 0.04 (SD) (P = .000). Median AL intra-OP aphakic vs 2 months post-OP pseudophakic was 23.42 mm ± 0.97 (SD) vs 23.42 mm ± 0.97 (SD), respectively. Absolute median difference was 0.038 ± 0.04 (SD) (P = .379). CONCLUSIONS: Intra-OP, SS-OCT technology of the phakic and aphakic eye shows excellent comparability to preoperative and postoperative measurements. This technique allows AL measurements with high precision in cases in which preoperative biometric measurements are not possible.

Visual Performance of Two Diffractive Trifocal Intraocular Lenses: A Randomized Trial.

PURPOSE: To compare two trifocal intraocular lenses (IOLs), the RayOne Trifocal RAO603F IOL (closed-loop haptic IOL; Rayner Intraocular Lenses Limited) and the AT Lisa tri 839 MP IOL (plate-haptic IOL; Carl Zeiss Meditec AG), concerning optical and capsular bag performance. METHODS: Patients scheduled for cataract surgery received either a closed-loop haptic IOL or a plate-haptic IOL in the first eye and the other IOL in the second eye. Three months postoperatively, autorefraction and subjective refraction, uncorrected and corrected distance visual acuity at 4 m, 80 cm, and 40 cm, an objective reading test (Salzburg Reading Desk; SRD Vision), a defocus curve, IOL tilt and decentration, a questionnaire about dysphotopsia, and grading of halos with a halometer were performed. RESULTS: Eighty-eight eyes of 44 patients were included. Visual acuity was comparable between both IOLs. The closed-loop haptic IOL performed better in the defocus curve at -1.50 diopters (D) (0.08 ± 0.10 vs 0.12 ± 0.09 logMAR; P < .01). The plate-haptic IOL had better contrast sensitivity without glare under mesopic and photopic conditions in miosis (P = .0018 and .002, respectively) and mydriasis (P = .017 and .003, respectively). Significant differences were found for less overall subjective disturbance (P = .047) and starbursts (P = .039) for the plate-haptic IOL, but not for the other positive dysphotopsia symptoms. CONCLUSIONS: Both trifocal IOLs delivered good and comparable visual function with low degrees of disturbing dysphotopsia. The closed-loop haptic IOL was slightly superior in the defocus curve, whereas the plate-haptic IOL was slightly superior concerning contrast sensitivity and positive dysphotopsia. [J Refract Surg. 2021;37(7):460-465.].

Anterior chamber depth variability between 2 hydrophobic acrylic 1-piece intraocular lenses: randomized trial.

PURPOSE: To analyze the difference in anterior chamber depth (ACD) after uneventful cataract surgery between 2 hydrophobic acrylic 1-piece intraocular lenses (IOLs) with different material properties. SETTING: Hanusch Hospital, Vienna, Austria. DESIGN: Single-center, bilateral randomized paired-eye controlled study. METHODS: Patients scheduled for bilateral cataract surgery were randomized to receive the Clareon IOL in 1 eye and the AcrySof IQ IOL (both Alcon Laboratories, Inc.) in the contralateral eye. Preoperatively, a slitlamp examination, optical biometry (IOLMaster 700, Carl Zeiss Meditec AG), refraction, and visual acuity measurements were performed. ACD was assessed 1 hour and 1 week postoperatively and with additional measurement of uncorrected (UDVA) and corrected distance visual acuity (CDVA) 6 months postoperatively. RESULTS: 80 eyes of 40 patients were analyzed in this study. ACD at the 6-month follow-up was 3.94 ± 0.30 mm for the Clareon IOL and 3.91 ± 0.32 mm for the AcrySof IQ IOL (P = .08). Statistically significant differences in the ACD shift between both IOLs were detected between 1 week and 6 months (P = .04) and 1 hour and 6 months (P = .04). There were no statistically significant differences between both IOLs in UDVA (P = .78), CDVA (P = .59), and spherical equivalent (SE, P = .39) at the 6-month visit. The mean absolute error between the measured and the aimed SE was not significant (P = .97). CONCLUSIONS: There was no clinically relevant difference in ACD between the Clareon IOL and the AcrySof IQ IOL in patients after uneventful cataract surgery. Both IOLs yielded good refraction and visual acuity outcomes.

Prospective study to compare axial position stability after fellow-eye implantation of 2 distinct intraocular lens designs.

PURPOSE: To compare the dynamics of axial intraocular lens (IOL) position and stability in the capsular bag after fellow-eye implantation of a 1-piece C-loop and a 4-point haptic IOL. SETTING: Hanusch Hospital, Vienna. DESIGN: Prospective, comparative, randomized bilateral study. METHODS: One hundred eyes of 50 patients were randomly implanted with a C-loop IOL (CT LUCIA 611P) in 1 eye and a 4-point haptic IOL (CT ASPHINA 409MP) in the other eye. Anterior chamber depth (ACD) was measured at 1 week (W1), 1 month (M1), and 4 to 6 months (M4-6) postoperatively using a swept-source optical coherence tomography device (IOLMaster 700). Uncorrected distance visual acuity (UDVA), corrected distance visual acuity, and subjective refraction outcomes were assessed at M4-6 postoperative follow-up. RESULTS: Hundred eyes of 50 patient were included. Pseudophakia ACD values at W1, M1, and M4-6 timepoints were significantly different in eyes implanted with the C-loop IOL compared with the 4-point haptic IOL (P < .001). The overall IOL shift was 0.25 ± 0.16 mm for the 4-point haptic IOL and 0.14 ± 0.09 mm for the C-loop IOL (P < .001). The M4-6 mean monocular UDVA outcome for eyes with C-loop IOL was 0.06 ± 0.14 logarithm of the minimum angle of resolution (logMAR) and 0.03 ± 0.10 logMAR for the eyes with 4-point haptic IOL. M4-6 mean spherical equivalent was -0.32 ± 0.48 diopter (D) in the C-loop IOL group and -0.33 ± 0.42 D in the 4-point haptic IOL group. CONCLUSIONS: Statistically significant differences in IOL design results in different postoperative ACD values. No relevant or statistically significant differences were found in refraction or visual acuity between the groups.

Repeatability of intraoperative Hartmann-Shack wavefront sensing in cataract surgery.

PURPOSE: To evaluate the repeatability of aphakic intraoperative wavefront aberrometry and compare it with preoperative and postoperative aberrometry. SETTING: Department of Ophthalmology, Hanusch Hospital, Vienna, Austria. DESIGN: Prospective case series. METHODS: Patients scheduled for cataract surgery were each measured 3 consecutive times using Hartmann-Shack wavefront sensing (HS-WFS) preoperatively, intraoperatively in aphakia, and 2 months postoperatively after intraocular lens implantation by a single examiner. Intraclass correlation coefficients (ICCs) of spherical equivalent (SE) values were evaluated for each timepoint. Intrasubject standard deviation (Sw) as repeatability (Sr) with corresponding repeatability limit () and mean SE differences with corresponding limits of agreement (LoA) were calculated for comparison. RESULTS: A high consistency of repeated measurements was found with ICCs above 0.9 for each of the 3 timepoints. Intraobserver repeatability (Sr) and repeatability limit (r) of intraoperative aberrometry SE measurements (30 eyes of 30 patients) were 0.34 diopters (D) and 0.95 D, respectively. The LoA for intraoperative aphakic SE across 3 consecutive measurements were -0.71 to +0.85 D. For comparison, Sr and r for phakic preoperative measurements in the cataractous state (30 eyes of 30 patients) and postoperative measurements in the pseudophakic state (24 eyes of 24 patients) were 0.33 D and 0.93 D and 0.23 D and 0.64 D, respectively. Similarly, the LoA for preoperative and postoperative SE measurements were -0.66 to +0.60 D and -0.27 to +0.45 D, respectively. CONCLUSIONS: HS-WFS test-retest reliability was high for all 3 timepoints, but the intraoperative setting resulted in a lower repeatability and broadened the agreement range.

Effect of Iatrogenic Traction during Macular Peeling Surgery on Postoperative Microperimetry.

INTRODUCTION: Vitrectomy with peeling of epiretinal membrane (ERM) and internal limiting membrane offers the chance for improvement of metamorphopsia and visual acuity. Microscope integrated intraoperative optical coherence tomography (iOCT) enables real-time imaging of retinal alterations during peeling, such as intraoperative transient retinal thickening owing to tractional forces during peeling. The aim of our study was to measure the amounts of transient retinal thickening due to tractional forces during membrane peeling, as documented with iOCT, and to analyze possible effects on postoperative retinal function. METHODS: This prospective, monocenter study included patients scheduled for pars plana vitrectomy with membrane peeling due to an idiopathic ERM. During peeling, an iOCT device (ReScan700, Carl Zeiss Meditec AG) with continuous OCT-assistance during the peeling procedure, and video documentation of the peeling procedure, was used for the assessment of intraoperative transient retinal thickening owing to tractional forces during peeling. Directly before and 3 months after surgery, macular-OCT scans and microperimetry were performed. RESULTS: Twenty-five eyes of 25 patients were included in the study. Microperimetry could be performed in all patients, while iOCT documentation could be analyzed in 22 patients. Transient retinal thickening owing to tractional forces during peeling could be observed in 14 patients (64%), with a median thickening to 143% of the normal (preoperative) retinal thickness at that location (IQR 132-163). Six patients (24%) developed new deep microscotomata as seen in microperimetry 3 months after surgery, among them were 2 patients who also had transient retinal thickening during peeling. CONCLUSION: New deep microscotomata developed only in a minority of patients with transient retinal thickening owing to tractional forces during peeling.

Caffeine Uptake into the Vitreous after Peroral Coffee Consumption.

INTRODUCTION: Caffeine and its metabolites have antioxidant activity, scavenging reactive oxygen species. The aim of our study was to measure caffeine concentrations in vitreous samples after peroral caffeine intake. METHODS: This prospective study included patients scheduled for 23-G pars plana vitrectomy with membrane peeling due to epiretinal membranes. The study was performed in two parts: in the first part, patients were recruited into three different groups: group A consisted of habitual coffee drinkers who agreed to drink coffee containing 180 mg caffeine 1 h before surgery (n = 10), group B consisted of habitual coffee drinkers who were not offered coffee before surgery (n = 5), and group C consisted of non-habitual coffee drinkers, forming the control group (n = 5). In the second part (group D) patients (habitual coffee drinkers) agreed to give additional blood serum samples for measurement of caffeine concentration. Harvested samples of vitreous (groups A-D), epiretinal membranes (groups A-C), and blood serum samples (group D) were examined for concentrations of caffeine with gas chromatography-mass spectrometry. RESULTS: Samples of 40 eyes of 40 patients were harvested. The concentrations of caffeine in the vitreous samples were 1,998 ± 967 ng/mL in group A and 1,108 ± 874 ng/mL in group B. In group C, caffeine concentrations were below 176 ng/mL in all vitreous samples. Both groups A and B had significantly higher concentrations of caffeine in the vitreous samples than group C (p < 0.002, p < 0.01, Mann-Whitney U test). Caffeine concentrations in epiretinal membranes were below the limits of detection. Correlation of caffeine concentrations between blood serum samples and vitreous samples in group D was high, with significantly higher caffeine concentrations in the blood serum. CONCLUSION: Coffee consumption leads to significant caffeine levels in the vitreous compared to patients in the control group, and caffeine concentrations in the vitreous showed a high correlation to blood serum concentrations of caffeine after peroral coffee consumption.

Remodelling intravitreal therapy pathways for macular disease during the COVID-19 pandemic and an Austrian national lockdown.

OBJECTIVE: To analyse the remodelling and recovery of a relocated intravitreal injection (IVI) service with an adapted treatment regimen in a tertiary referral centre during a nationwide lockdown with initial cancellation of all non-emergency treatments caused by the COVID-19 pandemic. METHODS AND ANALYSIS: For this retrospective observational study at Hanusch Hospital, Vienna, between 16 March 2020 and 5 May 2020, we conducted an analysis of an appointment booking system based on prioritisation incorporating disease class, severity and fellow eye status by evidence-based impact on irreversible structural impairment and survey data from telephone interviews. Recapture time was defined as the time-to-discard the backlog of patients in need for treatment. Non-attendance was stratified as treatment refusal for personal reasons and non-attendance due to lockdown-related restrictions. RESULTS: Of the 1109 patients, 241 (21.7%) were considered as highly urgent, 269 (24.3%) as urgent, 402 (36.2%) as semiurgent and 197 (17.8%) as non-urgent. Recapture time was 15 days for highly urgent patients, 22 days for urgent patients, 43 days for semiurgent patients and 46 days for non-urgent patients. The proportion of patients who refused treatment due to personal reasons was 5.2%, with a mean age of 82.4 years; 29 patients (2.6%) could not attend due to lockdown-related restrictions. CONCLUSION: By streamlining treatment based on urgency as well as increasing the number of bilateral IVI, recapture time was fast. We could provide a safe treatment environment for healthcare professionals and patients after resetting the injection service outside of the hospital with increased levels of protection.

One-Year Results after Internal Limiting Membrane Flap Transposition for Surgical Repair of Macular Holes with Respect to Microperimetry.

PURPOSE: Internal limiting membrane (ILM) flap transposition in surgical repair of macular holes represents a new technique offering good anatomical success rates with large macular holes. The aim of the study was to examine microperimetric outcomes 1 year after ILM flap transposition for surgical repair of macular holes. METHODS: Patients with idi-opathic macular holes scheduled for 23-G pars plana vitrectomy with ILM peeling, ILM flap transposition, and SF6 tamponade were examined in a prospective case series. Distance corrected visual acuity (DCVA), optical coherence tomography, and microperimetry were measured before and 1 year after surgery. RESULTS: In all eyes, closure of the macular hole could be achieved. While foveal sensitivity improved in 71%, perifoveal sensitivity improved in 86% of the cases. DCVA improved in 83% and was unchanged in 17% of the cases. CONCLUSIONS: Beside visual acuity, foveal and perifoveal macular sensitivity improved, underlining the functional success of surgery after ILM peeling with ILM flap transposition.

Intraoperative optical coherence tomography measurements of aphakic eyes to predict postoperative position of 2 intraocular lens designs.

PURPOSE: To evaluate intraoperative anterior chamber depth (ACD) measurements of the aphakic eye to predict the postoperative ACD and compare 2 intraocular lens (IOL) designs. SETTING: Hanusch Hospital, Vienna, Austria. DESIGN: Prospective study. METHODS: In this prospective study, patients scheduled for cataract surgery received a plate-haptic IOL (Asphina, Carl Zeiss Meditec AG) or an open-loop haptic IOL (ZCB00, Johnson & Johnson). Preoperatively, optical biometry (IOLMaster 700, CZM, or Lenstar, Haag-Streit) was performed. Intraoperatively, a prototype setup was used to perform time-domain OCT scans of the anterior eye segment (Visante connected to OPMI Lumera 200, both CZM). The intraoperative ACD was measured and used to predict the postoperative IOL position. Optical biometry and subjective refraction and autorefraction (RM 8800, Topcon) were performed 2 months postoperatively. RESULTS: The study comprised 203 eyes of 203 patients. A partial least-square regression model for ACD generated 2 months postoperatively showed that the predictive power of the intraoperative ACD (0.48) was highest followed by the axial eye length (0.45) and then the preoperatively measured ACD (0.30). These findings were confirmed in a bootstrapping model. Regression models combining the preoperative ACD and intraoperative ACD resulted in further significant improvement. CONCLUSIONS: Intraoperative ACD measurements predicted the postoperative position of open-loop IOLs and plate-haptic IOLs better than preoperative ACD measurements. Combining preoperative and intraoperative ACD measurements further improved the prediction.

Influence of disc-fovea angle and retinal blood vessels on interindividual variability of circumpapillary retinal nerve fibre layer.

BACKGROUND: To assess whether intersubject variability of circumpapillary retinal nerve fibre layer (RNFL) thickness in healthy subjects acquired with spectral domain optical coherence tomography (SD-OCT) can be reduced by considering the disc-fovea angle (DFA), either alone or together with a compensation based on retinal blood vessel distribution (RVD). METHODS: 106 healthy volunteers underwent SD-OCT examination centred on the optic disc (OD) and on the macula. OD contours and foveal positions were automatically calculated. RVD at 3.4 mm diameter circle was manually assessed. We made two approaches to reduce interindividual variability in RNFL values using compensation processes; RVD compensation: RNFL thickness values were compensated according to RVD variation (RNFLRVD) and DFA compensation: we shifted the RNFL thickness measurements according to the DFA (RNFLDFA). Coefficient of variance (CoV) was calculated in 12 clock hour sectors for original RNFL (RNFLo), RNFLDFA, RNFLRVD and RNFL with both compensation methods (RNFLDFA-RVD). RESULTS: Compared with the mean CoV of RNFLO, mean CoV of RNFLDFA, RNFLRVD and RNFLDFA-RVD was changed by -0.71% (p>0.05), -9.51% (p<0.001) and -7.55% (p=0.001), respectively. When compared with RNFLDFA, RNFL DFA-RVD significantly reduced the mean CoV by -6.69% (p=0.001), while compared with RNFLRVD, RNFL DFA-RVD did not significantly increase the mean CoV (+2.20%), (p>0.05). CONCLUSIONS: Although reaching an improvement in some sectors, rotation of RNFL measurements according to the DFA on average does not reduce intersubject variability of RNFL. However, adjusting for RVD reduced the variance significantly. The results reinforce our work in assessing RVD as an important anatomical factor responsible for intersubject variability in RNFL measurements.