Μελέτη του Contrast Sensitivity (ευαισθησία αντιθέσεων) και Aberration (εκτροπών κερατοειδούς) σε σχέση με τις μεταβολές του πάχους του επιθηλίου Corneal Apex και στο Pupil Center μετά από PRK και Lasik

2021 ◽  
Author(s):  
Θεμιστοκλής Γιαλελής
Keyword(s):  
Contrast Sensitivity ◽  
Pupil Center ◽  
Corneal Apex

Η διαθλαστική χειρουργική με χρήση των τεχνικών LASIK και PRK είναι ένα ταχύτατα αναπτυσσόμενο πεδίο της οφθαλμολογίας. Η αποτελεσματικότητα των επεμβάσεων και η προβλεψιμότητα του διαθλαστικού αποτελέσματος, σχετίζεται στενά με τον ακριβή έλεγχο της επουλωτικής αντίδρασης του κερατοειδή μετά το εισαγόμενο χειρουργικό τραύμα και ειδικά του επιθηλίου. Σκοπός: Ο σκοπός της εργασίας είναι η μελέτη των επιπτώσεων της διαθλαστικής χειρουργικής στην ευαισθησία αντίθεσης (C. S) του οφθαλμού λαμβάνοντας υπ όψη τη μεταβολή των εκτροπών σε συνάρτηση με την μεταβολή του πάχους του επιθηλίου στην κορυφή του κερατοειδούς (ET peak) και στο κέντρο της κόρης (ET center) που θα προκύψει μετά από διαθλαστικές επεμβάσεις (LASIK και PRK). Μελετώνται και συγκρίνονται οι μέθοδοι διόρθωσης οπτικής οξύτητας PRK και LASIK. Μεθοδολογία: Πενήντα εννέα ασθενείς (118 οφθαλμοί) με μέση ηλικία 31,39 +/- 6,95 (εύρος από 23 έως 50 έτη), 26 άνδρες και 33 γυναίκες συμπεριλήφθηκαν στη μελέτη. Είκοσι εννέα ασθενείς (29) υποβλήθηκαν σε επέμβαση LASIK και τριάντα ασθενείς (30) υποβλήθηκαν σε επέμβαση PRK. Όλοι οι ασθενείς εξετάστηκαν το χρονικό διάστημα από το Νοέμβριο του 2016 ως τον Ιούλιο του 2019. Η έρευνα είναι σύμφωνα με τη διακήρυξη του Ελσίνκι. Όλοι οι ασθενείς είχαν σταθερή διάθλαση για τουλάχιστον 2 χρόνια. Ασθενείς που ήταν σε κατάσταση εγκυμοσύνης ή είχαν συστηματική νόσο ή ιστορικό προηγούμενης οφθαλμικής νόσου ή χειρουργικής επέμβασης εξαιρέθηκαν από τη μελέτη. Η παρακολούθηση του κάθε περιστατικού έγινε για ένα χρόνο και με επανεξέταση του στην εβδομάδα, μήνα, τρίμηνο, εξάμηνο και χρόνο. Στη συγκεκριμένη έρευνα όλοι οι συμμετέχοντες υποβλήθηκαν σε προεγχειρητικό έλεγχο ο οποίος περιλάμβανε εξέταση του κάθε ενός οφθαλμού με τη συσκευή Pentacam HR προκειμένου να ληφθούν πληροφορίες τόσο από τον χάρτη “four maps refractive” όσο και από τον χάρτη των πολυωνύμων Zernike σχετικά με τις εκτροπές. Χρησιμοποιώντας την εφαρμογή Fract σε ηλεκτρονικό υπολογιστή ελήφθησαν μετρήσεις, εξετάζοντας κάθε ένα οφθαλμό ξεχωριστά, αλλά και διόφθαλμα - οπτικής οξύτητας (CDVA) αλλά και CS. Ακολούθως οι ασθενείς εξετάστηκαν ως προς το πάχος του επιθηλίου ET peak και στο ET center με το Oct Agiovue Avanti με φακό προσθίου ημιμορίου. Η εξέταση περιλάμβανε τον κάθε οφθαλμό ξεχωριστά. Οι ίδιες εξετάσεις επαναλήφθηκαν και στους μετεγχειρητικούς ελέγχους ώστε να προσδιοριστούν οι μεταβολές που πιθανόν προκάλεσε η επούλωση του επιθηλίου στην CDVA αλλά και στο CS. Όλες οι μεταβλητές εξετάστηκαν κατά την στατιστική ανάλυση με τη δοκιμασία Kolmogorov για κανονικότητα και έδειξαν ότι δεν ακολουθούν κανονική κατανομή. Χρησιμοποιήθηκε για την στατιστική ανάλυση το ειδικό στατιστικό λογισμικό SPSS v.26, και έγινε στατιστική ανάλυση spearman όπου μεταξύ των μεταβλητών διαπιστώθηκε σημαντική στατιστική διαφορά. Αποτελέσματα:Τόσο στο ET peak όσο και στο ET center τα αποτελέσματα μοιάζουν πολύ ως προς τη μεταβολή του E.T. Βρέθηκαν στατιστικά σημαντικές διαφορές μεταξύ των προεγχειρητικών και μετεγχειρητικών τιμών σε C.S, E.T και στις εκτροπές ανώτερης τάξης (HOAs) και στις δύο μεθόδους διαθλαστικής χειρουργικής. Στην ομάδα PRK, η μέση αύξηση του E.T peak ήταν 6,62 ± 1,31 microns και του E.T center : 6.39±1.32 microns και φάνηκαν να σχετίζεται με αλλαγή στο C.S και με αλλαγές στις εκτροπές, LOAs (Ζ00, Ζ02, Ζ11) και HOAs (Ζ31 και Ζ42). Ωστόσο, η αλλαγή στο επιθήλιο δεν φάνηκε να επηρεάζει το CDVA. Στην ομάδα LASIK, η μέση αύξηση του E.T peak ήταν 6,55±1,26 microns και του E.T center ήταν 6,03±1,22 microns αλλά δεν βρέθηκε καμία συσχέτιση με τη μείωση του C.S, τις αλλαγές στα HOAs και CDVA. Ωστόσο, υπήρξε συσχέτιση με την αύξηση του ET και των LOAs (Ζ00, Ζ02, Ζ11). Συμπεράσματα : Οι τεχνικές PRK και LASIK βρέθηκαν να έχουν παρόμοια μετεγχειρητική αύξηση E.T. Τόσο στο E.T peak όσο και στο E.T center στην PRK οι αλλαγές φάνηκε να συσχετίζονται ισχυρά με το C.S σε αντίθεση με το LASIK. Επίσης η διαφορά στην μεταβολή του C.S και των εκτροπών εκτός της μεταβολής του ET peak και ET center μεταξύ των δυο τεχνικών μπορεί να σχετίζεται με την αλλαγή στο σχήμα του κερατοειδούς, τη μετατροπή της εμβιομηχανικής, την επούλωση του κρημνού του κερατοειδούς αλλά και την ανακατασκευή του επιθηλίου και του στρώματος του κερατοειδούς. Τέλος οι αλλαγές του ET peak και οι αλλαγές στο ET center επηρέασαν τις εκτροπές και στις δύο τεχνικές, αλλά όχι με τον ίδιο τρόπο.

scholarly journals The impact of irregular corneal shape parameters on visual acuity and contrast sensitivity

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Sanita Liduma ◽  
Artis Luguzis ◽  
Gunta Krumina
Keyword(s):  
Visual Acuity ◽  
Contrast Sensitivity ◽  
Cross Sectional Study ◽  
Shape Parameters ◽  
Corneal Surface ◽  
Cross Sectional ◽  
Corneal Shape ◽  
Different Diameters ◽  
The Impact ◽  
Corneal Apex

Abstract Background To understand which irregular corneal parameters determine the visual quality in keratoconus subjects. Methods The cross-sectional study examined the eyes of 44 subjects, graded from the first to third keratoconus stages by Amsler-Krumeich classification. We obtained measurements in two ways: (a) by projecting two perpendicular axes onto a cornea (first, through the central point of the cornea and keratoconus apex; second, as the perpendicular axis) to read the elevation values at points on these axes as parameters characterising the corneal surface; (b) by projecting circles with different diameters around the central part of the cornea (1, 2, and 3 mm) and reading elevation values at points equally displaced on these circles as parameters characterising an anterior surface slope. Irregular corneal shape parameters’ correlations with visual acuity and contrast sensitivity were determined in order to understand which corneal slope parameter has the strongest correlation with visual acuity and contrast sensitivity. Results Parameters characterising the corneal surface’s correlations with contrast sensitivity were from r = 0.25 (p = 0.03) at 3 cpd to r = 0.47 (p < 0.01) at 9 cpd for the highest elevation and from r = 0.33 (p = 0.09) at 5 cpd to r = 0.40 (p < 0.01) at 11 cpd for the lowest elevation in all subjects together, while for visual acuity the parameters were r = 0.30 (p < 0.01) for the highest elevation and r = 0.21 (p = 0.06) for the lowest elevation in all subjects together. The correlation between contrast sensitivity and the highest and lowest corneal point in all measured cornea was stronger for subjects with a peripheral corneal apex than for those with a central apex. In keratoconus subjects, contrast sensitivity displayed a strong correlation with slope in the central part of the cornea (with a radius of 1 mm) ranging from 0.48 (p < 0.01) at 3 cpd to 0.61 (p < 0.01) at 9 cpd. Conclusion Contrast sensitivity has a higher correlation with corneal shape parameters than with visual acuity. Subjects with a peripheral corneal apex had stronger correlations with visual acuity and contrast sensitivity than did subjects with a central apex. In keratoconus subjects, the strongest correlation was for contrast sensitivity and elevation (slope) in the region within a 1 mm radius of the corneal centre in the opposite direction of the keratoconus apex (direction (ax) CB).

scholarly journals Corneal thickness evaluation in healthy eyes: Comparison between two different Scheimpflug devices

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0243370
Author(s):  
Nicola Rosa ◽  
Maddalena De Bernardo ◽  
Angela Pepe ◽  
Livio Vitiello ◽  
Giuseppe Marotta ◽  
...  
Keyword(s):  
Observational Study ◽  
Corneal Thickness ◽  
Pupil Center ◽  
Regression Formula ◽  
Ct Measurements ◽  
Corneal Apex ◽  
Thickness Evaluation ◽  
Healthy Eyes

Purpose To evaluate the correlation between corneal thickness (CT) measurements obtained with two Scheimpflug devices, Pentacam HR and Precisio, and to elaborate, if necessary, a regression formula which could make these results comparable. Design Retrospective, Comparative, Observational study. Setting Department of Medicine, Surgery and Dentistry, “Scuola Medica Salernitana” University of Salerno, Italy Methods One hundred twenty four healthy eyes of 124 volunteers (65 males; range: 20–32 years; mean age of 24.8 ± 1.7) were included in this study. CT was measured using Pentacam HR and Precisio in three different points: the pupil center (PC), the corneal apex (CA) and the thinnest point (TP). Results CT obtained with both devices at the PC, at the CA and at the TP showed a good correlation (r = 0.97, r = 0.97, r = 0.97, respectively), but Pentacam HR measurements were significantly thicker than those provided by Precisio (p < 0.01). The differences between Pentacam HR and Precisio were 21.9 ± 8.8 μm at the PC, 21.9 ± 8.9 μm at the CA, 19.1 ± 9.0 μm at the TP. The calculated regression formulas were: y = 0.9558x + 2.3196 for the PC, y = 0.9519x + 4.5626 for the CA, y = 0.9364x + 15.436 for the TP, where x is the CT measured with Pentacam HR and y is the Precisio measurement. Conclusions The findings provided by this study highlight that Precisio measures thinner corneas compared to Pentacam HR. The identified regression formulas could be utilized to make interchangeable the results obtained with these two devices.

scholarly journals Measurement of corneal thickness using Pentacam HR versus Nidek CEM-530 specular microscopy

2019 ◽  
Vol 48 (4) ◽  
pp. 030006051989238
Author(s):  
Maddalena De Bernardo ◽  
Palmiro Cornetta ◽  
Giuseppe Marotta ◽  
Giulio Salerno ◽  
Ilaria De Pascale ◽  
...  
Keyword(s):  
Healthy Subjects ◽  
Corneal Thickness ◽  
Random Order ◽  
Time Of Day ◽  
Specular Microscopy ◽  
Pupil Center ◽  
Ct Measurements ◽  
Significant Difference ◽  
Corneal Apex

Objective To compare corneal thickness (CT) measurements using the CEM-530 (Nidal, Gamagori, Japan) and Pentacam HR (Oculus, Wetzlar, Germany). Methods The CT of 209 healthy subjects (209 right eyes) aged 24 to 89 years (71.35 ± 10.72 years) was measured at the corneal apex (CA), pupil center (PC), and thinnest point (TP) with the Pentacam HR and at the corneal center with the CEM-530 in random order at the same time of day. Results A good correlation but statistically significant difference was found between the CEM-530 and Pentacam HR measurements at the CA (6.10 ± 8.12 µm, R2 = 0.8947), PC (7.46 ± 8.57 µm, R2 = 0.8826), and TP (12.44 ± 10.04 µm, R2 = 0.8392). Comparison of the two devices produced the following regression formulas: y = 0.8859x + 57.644 for the CA, y = 0.8852x +56.657 for the PC, and y = 0.8557x + 68.148 for the TP, where x is the CT obtained with the CEM-530 and y is that obtained with the Pentacam HR. Conclusions These findings indicate that the CEM-530 produces a thicker corneal measurement than the Pentacam HR. The herein-proposed correcting factors are needed to reliably compare these devices.

scholarly journals The Influence of Analysis Mode Selection on Prediction Accuracy of Corneal Astigmatism Using Pentacam

2021 ◽  
Vol 8 ◽  
Author(s):  
Jiaqi Meng ◽  
Jifeng Yu ◽  
Wenwen He ◽  
Ling Wei ◽  
Yi Lu ◽  
...  
Keyword(s):  
Prediction Error ◽  
Prediction Accuracy ◽  
Mode Selection ◽  
Corneal Astigmatism ◽  
Intraocular Lenses ◽  
Pupil Center ◽  
Local Topography ◽  
Ring Mode ◽  
Analysis Mode ◽  
Corneal Apex

Purpose: To evaluate the influence of analysis mode selection on prediction accuracy of corneal astigmatism using Pentacam.Methods: Fifty-nine eyes of 59 patients implanted with toric intraocular lenses (IOLs) were included in the retrospective study. Preoperative corneal astigmatism (total refractive power) measured with Pentacam was analyzed based on 2-, 3-, 4-, or 5-mm ring or zone mode either centered on corneal apex or pupil center. Actual corneal astigmatism was calculated based on residual astigmatism on the corneal plane, surgical-induced astigmatism, and effective toric power on the corneal plane. Prediction error, the difference between actual corneal astigmatism and measured astigmatism, was compared among different analysis modes. Influences of local topography on prediction error were also evaluated.Results: Based on the zone mode, prediction error was lower when centered on corneal apex than on pupil center at different diameters, whereas based on the ring mode, this difference was only seen at 2-mm cornea (all P &lt; 0.05). When centered on the corneal apex, the zone mode showed lower prediction error than the ring mode at 4- and 5-mm corneas (both P &lt; 0.001), regardless of asymmetric or symmetric astigmatism. In symmetric bowtie, the zone mode showed lower prediction error than the ring mode at 2-mm cornea of the small bowtie, and 4- and 5-mm corneas of the large bowtie (all P &lt; 0.05).Conclusions: For toric IOL planning, the corneal apex may be a better reference center. At a cornea diameter ≥4 mm, the zone mode is more accurate than the ring mode. Local topography affects prediction accuracy in the symmetric bowtie.

scholarly journals The Impact of Irregular Corneal Shape Parameters on Visual Acuity and Contrast Sensitivity

2020 ◽  
Author(s):  
Sanita Liduma ◽  
Artis Luguzis ◽  
Gunta Krumina
Keyword(s):  
Visual Acuity ◽  
Contrast Sensitivity ◽  
Cross Sectional Study ◽  
Shape Parameters ◽  
Corneal Surface ◽  
Cross Sectional ◽  
Corneal Shape ◽  
Different Diameters ◽  
The Impact ◽  
Corneal Apex

Abstract Background: To understand which irregular corneal parameters determine the visual quality in keratoconus subjects.Methods: The cross-sectional study examined the eyes of 44 subjects, graded from the first to third keratoconus stages by Amsler-Krumeich classification. We obtained measurements in two ways: (a) by projecting two perpendicular axes onto a cornea (first, through the central point of the cornea and keratoconus apex; second, as the perpendicular axis) to read the elevation values at points on these axes as parameters characterising the corneal surface; (b) by projecting circles with different diameters around the central part of the cornea (1, 2, and 3 mm) and reading elevation values at points equally displaced on these circles as parameters characterising an anterior surface slope. Irregular corneal shape parameters’ correlations with visual acuity and contrast sensitivity were determined in order to understand which corneal slope parameter has the strongest correlation with visual acuity and contrast sensitivity.Results: Parameters characterising the corneal surface’s correlations with contrast sensitivity were from r=0.25 (p=0.03) at 3 cpd to r=0.47 (p<0.01) at 9 cpd for the highest elevation and from r=0.33 (p=0.09) at 5 cpd to r=0.40 (p<0.01) at 11 cpd for the lowest elevation in all subjects together, while for visual acuity the parameters were r=0.30 (p<0.01) for the highest elevation and r=0.21 (p=0.06) for the lowest elevation in all subjects together. The correlation between contrast sensitivity and the highest and lowest corneal point in all measured cornea was stronger for subjects with a peripheral corneal apex than for those with a central apex. In keratoconus subjects, contrast sensitivity displayed a strong correlation with slope in the central part of the cornea (with a radius of 1 mm) ranging from 0.48 (p<0.01) at 3 cpd to 0.61 (p<0.01) at 9 cpd.Conclusion: Contrast sensitivity has a higher correlation with corneal shape parameters than with visual acuity. Subjects with a peripheral corneal apex had stronger correlations with visual acuity and contrast sensitivity than did subjects with a central apex. In keratoconus subjects, the strongest correlation was for contrast sensitivity and elevation (slope) in the region within a 1 mm radius of the corneal centre in the opposite direction of the keratoconus apex (direction (ax) CB).

scholarly journals The Impact of Irregular Corneal Shape Parameters on Visual Acuity and Contrast Sensitivity

2020 ◽  
Author(s):  
Sanita Liduma ◽  
Artis Luguzis ◽  
Gunta Krumina
Keyword(s):  
Visual Acuity ◽  
Contrast Sensitivity ◽  
Strong Correlation ◽  
Visual Quality ◽  
Main Axis ◽  
Shape Parameters ◽  
Visual Axis ◽  
Corneal Shape ◽  
The Impact ◽  
Corneal Apex

Abstract Background: To understand which irregular corneal parameters determine the visual quality in keratoconus subjects. Methods: The cross-sectional study examined thecovered eyes of 44 subjects, graded from the first to third keratoconus stages by Amsler-Krumeich classification. To characterize the shape of cornea, wWe obtained measurements in two ways: (a) by projectinged two perpendicular axes onto a cornea (– the main axis passed first, through the central point of the cornea (visual axis projection) and keratoconus apex; second, as , while the second axis was perpendicular to the main axis) to – and read the elevation values at points on theses axeis as parameters characterising the corneal surface; (b) by projectinged circles with different diameters around the central part of the cornea (1, 2, and 3 mm) and reading elevation values at points equally displaced on these circles as parameters characterising an anterior surface slope. Irregular corneal shape parameters’ correlations with visual acuity and contrast sensitivity were determined The measurements were used to calculate various elevation change (slope) parameters, in order to understand which corneal slope parameter has the strongest correlation with visual acuityquality and contrast sensitivity.Results: According to the acquired data, the visual acuity of a corrected eye does not have a strong correlation with the measured keratoconus apex slope. Parameters characterising the corneal surface’s correlations with contrast sensitivity were from r=0.25 (p=0.03) at 3 cpd to r=0.47 (p<0.01) at 9 cpd for the highest elevation and from r=0.33 (p=0.09) at 5 cpd to r=0.40 (p<0.01) at 11 cpd for the lowest elevation in all subjects together, while for visual acuity the parameters were r=0.30 (p<0.01) for the highest elevation and r=0.21 (p=0.06) for the lowest elevation in all subjects together. The correlation between contrast sensitivity and the highest and lowest corneal point in all measured cornea was stronger for subjects with a peripheral corneal apex than for those with a central apex. In keratoconus subjects, Ccontrast sensitivity displayed a strong correlation with keratoconus slope in the central part of the cornea (with a radius of 1 mm). Correlations in different spatial frequencies ranging from 0.48 (p<0.01) at 3 cpd to 0.61 (p<0.01) at 9 cpd.Conclusion: Contrast sensitivity has a higher correlation with corneal shape parameters than with is more important parameter which describes the visual quality of keratoconus subjects than visual acuity. Subjects with a peripheral corneal apex had stronger correlations with visual acuity and contrast sensitivity than did subjects with a central apex. In keratoconus subjects, Tthe strongest correlation was for contrast sensitivity and elevation (slope) in the region most important region which determines the visual quality in keratoconus subjects is the region within a 1 mm radius of the corneal centre in the opposite direction of the keratoconus apex (direction (ax) CB).

scholarly journals The Impact of Irregular Corneal Shape Parameters on Visual Acuity and Contrast Sensitivity

2020 ◽  
Author(s):  
Sanita Liduma ◽  
Artis Luguzis ◽  
Gunta Krumina
Keyword(s):  
Visual Acuity ◽  
Contrast Sensitivity ◽  
Cross Sectional Study ◽  
Shape Parameters ◽  
Corneal Surface ◽  
Cross Sectional ◽  
Corneal Shape ◽  
Different Diameters ◽  
The Impact ◽  
Corneal Apex

Abstract Background: To understand which irregular corneal parameters determine the visual quality in keratoconus subjects. Methods: The cross-sectional study examined the eyes of 44 subjects, graded from the first to third keratoconus stages by Amsler-Krumeich classification. We obtained measurements in two ways: (a) by projecting two perpendicular axes onto a cornea (first, through the central point of the cornea and keratoconus apex; second, as the perpendicular axis) to read the elevation values at points on these axes as parameters characterising the corneal surface; (b) by projecting circles with different diameters around the central part of the cornea (1, 2, and 3 mm) and reading elevation values at points equally displaced on these circles as parameters characterising an anterior surface slope. Irregular corneal shape parameters’ correlations with visual acuity and contrast sensitivity were determined in order to understand which corneal slope parameter has the strongest correlation with visual acuity and contrast sensitivity.Results: .Parameters characterising the corneal surface’s correlations with contrast sensitivity were from r=0.25 (p=0.03) at 3 cpd to r=0.47 (p<0.01) at 9 cpd for the highest elevation and from r=0.33 (p=0.09) at 5 cpd to r=0.40 (p<0.01) at 11 cpd for the lowest elevation in all subjects together, while for visual acuity the parameters were r=0.30 (p<0.01) for the highest elevation and r=0.21 (p=0.06) for the lowest elevation in all subjects together. The correlation between contrast sensitivity and the highest and lowest corneal point in all measured cornea was stronger for subjects with a peripheral corneal apex than for those with a central apex. In keratoconus subjects, contrast sensitivity displayed a strong correlation with slope in the central part of the cornea (with a radius of 1 mm) ranging from 0.48 (p<0.01) at 3 cpd to 0.61 (p<0.01) at 9 cpd.Conclusion: Contrast sensitivity has a higher correlation with corneal shape parameters than with visual acuity. Subjects with a peripheral corneal apex had stronger correlations with visual acuity and contrast sensitivity than did subjects with a central apex. In keratoconus subjects, the strongest correlation was for contrast sensitivity and elevation (slope) in the region within a 1 mm radius of the corneal centre in the opposite direction of the keratoconus apex (direction (ax) CB).

scholarly journals Comparison between two devices in the detection of corneal thickness changes after cataract surgery

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Maddalena De Bernardo ◽  
Livio Vitiello ◽  
Giulia Abbinante ◽  
Ilaria De Pascale ◽  
Luigi Capasso ◽  
...  
Keyword(s):  
Cataract Surgery ◽  
Corneal Thickness ◽  
Specular Microscopy ◽  
Slit Lamp ◽  
Thickness Increase ◽  
Pupil Center ◽  
Scheimpflug Camera ◽  
Corneal Apex

AbstractThis study compared corneal thickness (CT) changes obtained with specular microscopy (SM) and a rotating Scheimpflug camera (RSC) after conventional phacoemulsification surgery (PS). One hundred sixty six eyes of 83 patients were analyzed before and one month after PS. One eye underwent PS, while the fellow phakic one was used as control. CT was measured with SM at the center of the cornea and with RSC at the pupil center, at the corneal apex and at the thinnest point. In the operated eye, SM showed a larger CT mean increase than those one detected at the three different measurements’ points evaluated by RSC. Inversely, in the fellow phakic eye, SM showed a greater CT mean decrease than those one registered by RSC at its three measurement’s points. Thus, one month after surgery, even if cornea appears clear at the slit-lamp, a significant thickness increase is still present. This is even more evident if the slight decrease of the fellow phakic eye is considered. The differences between the two devices are probably related to the different measured areas.

Sign in / Sign up

Export Citation Format

Share Document