Carracedo Rodríguez, Juan Gonzalo

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First Name
Juan Gonzalo
Last Name
Carracedo Rodríguez
Universidad Complutense de Madrid
Faculty / Institute
Óptica y Optometría
Optometría y Visión
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Now showing 1 - 10 of 10
  • Publication
    Signs and Symptoms of Dry Eye in Keratoconus Patients: A Pilot Study
    (Taylor & Francis, 2015-11) Carracedo Rodríguez, Juan Gonzalo; Recchioni, Alberto; Alejandre Alba, Nicolás; Martín Gil, Alba; Crooke, Almudena; Jiménez Alfaro-Morote, Ignacio; Pintor, Jesús
    Purpose: To compare signs and symptoms of dry eye in keratoconus (KC) patients versus healthy subjects. Methods: A total of 15 KC patients (KC group, n = 15 eyes) and 16 healthy subjects (control group, 16 eyes) were enrolled in this study. The Schirmer I test with no anesthetic, tear break-up time (TBUT), corneal staining characteristics, and ocular surface disease index (OSDI) scores were evaluated for both groups. Impression cytology, combined with/scanning laser confocal microscopy (LCM), was performed to evaluate goblet cell density, mucin cloud height (MCH), and goblet cell layer thickness (CLT). Finally, tear concentrations of di-adenosine tetraphosphate (Ap4A) were assessed. Results were statistically analyzed using Shapiro–Wilk and non-parametric Wilcoxon rank sum tests. Statistical significance was set at p < 0.05. Results: KC patients had lower tear volumes and greater corneal staining than did healthy subjects (p < 0.05). OSDI scores were 44.96 ± 8.65 and 17.78 ± 6.50 for the KC and control groups, respectively (p < 0.05). We found no statistically significant differences in TBUT between groups. Impression cytology revealed lower goblet cell densities in KC group patients versus control group subjects (84.88 ± 32.98 and 128.88 ± 50.60 cells/mm,2 respectively, p < 0.05). There was a statistically significant reduction in MCH and CLT in KC group patients compared with control group subjects. Ap4A tear concentrations were higher in KC group patients than in control group subjects (2.56 ± 1.10 and 0.15 ± 0.12 µM, respectively, p < 0.05). Conclusions: The parameters evaluated in this study indicate that KC patients suffer greater symptoms of dry eye and greater tear instability, primarily due to the decreased mucin production in their tears, than do healthy patients with no KC.
  • Publication
    Diadenosine polyphosphates after laser in situ keratomileusis and photorefractive keratectomy refractive techniques
    (John Wiley & Sons Ltd., 2014-02) Carracedo Rodríguez, Juan Gonzalo; Cacho, Isabel; Sánchez Naves, Juan; Pintor, Jesús
    Purpose:  To study the concentrations of diadenosine polyphosphates in the ocular surface after PRK and LASIK. Methods:  Sixty-one patients (30 males and 31 females) with ages ranging from 20 to 63 (34.04 ± 9.13 years) were recruited in Balear Institute of Ophthalmology, Palma de Mallorca, Spain. LASIK was performed in 92 eyes of 46 patients and PRK in 25 eyes of 15 patients. Variations in the levels of diadenosine polyphosphate (Ap4A and Ap5A), Schirmer I (Jones test), TBUT, corneal staining together with the Dry Eye Questionnaire to evaluate discomfort and dryness were studied. All tests were performed at the preoperative visit and at 1-day, 2-week, 1-month and 3-month postoperative visits. Results:  Ap4A showed a 5 and 3.5 fold increase at the 1-day visit for LASIK and PRK, respectively. LASIK patients continued having higher statistically significant concentrations (p = 0.01) all over the follow-up. Ap5A showed no significant differences at any visit. Tear volume decreased during the 3 months in LASIK. The PRK cases had a normal volume at 1 month. TBUT in LASIK increased at the 1-day visit (p = 0,002) and decreased from the 2 weeks onwards and for the PRK, decreased by a 35% at the 1-day visit and kept reduced for a month. Discomfort only increased at the 1-day visit (p = 0.007). Dryness frequency was similar in all visits. Conclusions:  Ap4A levels only are increased in refractive surgery patients during the first day after the surgery. This increasing suggests that Ap4A may help accelerating the healing process.
  • Publication
    Short-term Effect of Scleral Lens on the Dry Eye Biomarkers in Keratoconus
    (Lippincott Williams & Wilkins, 2016-02) Carracedo Rodríguez, Juan Gonzalo; Serramito Blanco, María; Martín Gil, Alba; Wang, Zicheng; Carballo Álvarez, Jesús; Pintor, Jesús
    Purpose: To evaluate the most important signs of dry eye, such as osmolarity, inflammation, and diadenosine tetraphosphate (Ap4A) concentration before and after wearing scleral lenses for 8 h in keratoconus patients. Methods: A pilot, experimental, short-term study involved 26 keratoconus patients (average age, 36.95 ± 8.95 years). They voluntarily enrolled in the study at the Optometry Clinic of the Faculty of Optics and Optometry in the University Complutense of Madrid. They were divided into two groups: patients with intrastromal corneal ring, the ICRS group, and patients without ICRS, the keratoconus (KC) group. Ocular Surface Disease Index questionnaire, the Schirmer test without anesthesia, tear break-up time, matrix metalloproteinase 9 (MMP-9) concentration, osmolarity, and Ap4A concentration were evaluated before and after wearing a scleral lens for 8 h. Results: The patients wore the scleral lenses from 6 to 9 h, with a mean of 7.59 ± 0.73 h. The mean scleral lens sag for all patients was 4310 ± 166.31 μm, ranging from 4200 μm to 4800 μm. No significant changes in the Schirmer test and tear break-up time were found for either group. Ocular Surface Disease Index scores were statistically lower after wearing scleral lenses for both groups (p < 0.05). A significantly lower osmolarity and a significant rise of MMP-9 concentration after wearing scleral lenses were found in both groups (p < 0.05). Diadenosine tetraphosphate concentration was lower after wearing the scleral lens in the KC group (p < 0.05) but no significant difference was found for the ICRS group (p > 0.05). Conclusions: Short-term scleral lens wearing improves the symptomatology and some signs of dry eye, such as osmolarity and Ap4A concentration. The increase of MMP-9 concentration could be caused by tear film stagnation and use of preserved saline.
  • Publication
    Clinical Performance of a New Hybrid Contact Lens for Keratoconus
    (Contact Lens Association of Ophthalmologists, Inc., 2014-01) Carracedo Rodríguez, Juan Gonzalo; González-Méijome, José Manuel; Lopes Ferreira, Daniela P.; Carballo Álvarez, Jesús; Batres Valderas, Laura
    OBJECTIVES: To compare the clinical performance of the Clearkone hybrid contact lens for the treatment of keratoconus against the habitual contact lens of the patients. METHODS: A total of 33 eyes from 18 patients were fitted with the Clearkone. High- and low-contrast visual acuity (HCVA and LCVA), central corneal thickness (CCT), and contrast sensitivity acuity (CSF) were recorded with habitual lenses (prestudy visit) and after 1 week, 15 days, and 1 month of wear of prescribed Clearkone. Subjective vision and comfort were rated using visual analogue scales (VAS). RESULTS: Three patients discontinued the study, one because of diffuse corneal staining after 1 day of use and the other two because of extreme discomfort. The rest of the patients completed the 1-month study. High contrast visual acuity and LCVA (logMAR) improved significantly from 0.16 ± 0.12 and 0.44 ± 0.22, respectively, with the patient's habitual contact lenses to -0.006 ± 0.058 and 0.23 ± 0.13 after 1 day wearing Clearkone, remaining significant during all follow-up visits (P<0.001; repeated measures analysis of variance [RM-ANOVA]). There were no statistically significant differences in the mean CCT. The improvement of CSF was statistically significant with hybrid contact lenses prescribed compared with the patient's habitual contact lenses (P<0.001; RM-ANOVA test). Improvement in VAS score, with prescribed Clearkone, was statistically significant for comfort (P=0.043; RM-ANOVA test), but not for the subjective vision (P=0.759; RM-ANOVA test). CONCLUSIONS: Clearkone provides an improvement in visual acuity, contrast sensitivity, and subjective comfort in patients with keratoconus when compared with other contact lens options. However, clinicians must get specific training to fit the lens and be aware of potential adverse events.
  • Publication
    Posterior cornea and thickness changes after scleral lens wear in keratoconus patients
    (Elsevier, 2018-05) Serramito Blanco, María; Carpena Torres, Carlos; Carballo Álvarez, Jesús; Piñero, David Pablo; Lipson, Michael; Carracedo Rodríguez, Juan Gonzalo
    Purpose: To evaluate the changes in the corneal thickness, anterior chamber depth and posterior corneal curvature and aberrations after scleral lens wear in keratoconus patients with and without intrastromal corneal ring segments (ICRS). Methods:Twenty-six keratoconus subjects (36.95 ± 8.95 years) were evaluated after 8 h of scleral lens wear. The subjects were divided into two groups: those with ICRS (ICRS group) and without ICRS (KC group). The study variables evaluated before and immediately after scleral lens wear included corneal thickness evaluated in different quadrants, posterior corneal curvature at 2, 4, 6 and 8 mm of corneal diameter, posterior corneal aberrations for 4, 6 and 8 mm of pupil size and anterior chamber depth. Results: There was a statistically significant corneal thinning (p < 0.05) in the inferior region of the KC group and in the superior region of the ICRS group. No change (p > 0.05) in the anterior chamber depth was found. The KC group showed a steepening (p < 0.05) in the temporal quadrant and a flattening that mainly affected to the superior-nasal quadrant. The ICRS group showed a steepening (p < 0.05) that mainly affected to the superior-nasal quadrant. Regarding posterior corneal aberrations, only changes (p < 0.05) in Z4 for 8 mm and Z8 for 4 mm were found in the KC group. Conclusions: Short-term scleral lens wear showed a thinning of the cornea and changes in the posterior corneal curvature affects different regions in keratoconus patients with and without ICRS.
  • Publication
    Effect of Melatonin and Analogues on Corneal Wound Healing: Involvement of Mt2 Melatonin Receptor
    (Taylor & Francis, 2015-01) Crooke, Almudena; Guzmán Aránguez, Ana Isabel; Mediero Muñoz, Aránzazu; Alarma-Estrany, Pilar; Carracedo Rodríguez, Juan Gonzalo; Pelaez, Teresa; Peral Cerdá, Assumpta; Pintor, Jesús
    Purpose: We have investigated the effect of melatonin and its analogues on rabbit corneal epithelial wound healing. Methods: New Zealand rabbits were anaesthetised and wounds were made by placing Whatman paper discs soaked in n-heptanol on the cornea. Melatonin and analogues (all 10 nmol) were instilled. Wound diameter was measured every 2 hours by means of fluorescein application with a Topcon SL-8Z slit lamp. Melatonin antagonists (all 10 nmol) were applied 2 hours before the application of the n-heptanol-soaked disc and then every 6 hours together with melatonin. To confirm the presence of MT2 receptors in corneal epithelial cells immunohistochemistry, Western blot and RT-PCR assays in native tissue and in rabbit corneal epithelial cells were performed. The tear components were extracted then processed by HPLC to quantify melatonin in tears. Results: Migration assays revealed that melatonin and particularly the treatment with the MT2 agonist IIK7, accelerated the rate of healing (p < 0.001). The application of the non-selective melatonin receptor antagonist luzindole and the MT2 antagonist DH97 (but not prazosin), prevented the effect of melatonin on wound healing (both p < 0.001). Immunohistochemistry, Western blot and RT-PCR assays showed the presence of MT2 melatonin receptor in corneal epithelial cells. In addition, we have identified melatonin in tears and determined its daily variations. Conclusions: These data suggest that MT2 receptors are implicated in the effect of melatonin on corneal wound healing regulating migration rate. This suggests the potential use of melatonin and its analogues to enhance epithelial wound healing in ocular surface disease.
  • Publication
    Post-lens tear turbidity and visual quality after scleral lens wear
    (Wiley, 2017-11) Carracedo Rodríguez, Juan Gonzalo; Serramito Blanco, María; Martín Gil, Alba; Wang, Zicheng; Rodríguez Pomar, Candela; Pintor, Jesús
    Background: The aim was to evaluate the turbidity and thickness of the post-lens tear layer and its effect on visual quality in patients with keratoconus after the beginning of lens wear and before lens removal at the end of eight hours. Methods: Twenty-six patients with keratoconus (aged 36.95 ± 8.95 years) participated voluntarily in the study. The sample was divided into two groups: patients with intrastromal corneal ring (ICRS group) and patients without ICRS (KC group). Distance visual acuity (VA), contrast sensitivity, pachymetry, post-lens tear layer height and post-lens tear layer turbidity (percentage area occupied and number of particles per mm2) were evaluated with optical coherence tomography before and after wearing a scleral lens. Results: A significant increase of turbidity was found in all groups assessed (p < 0.05). The number of particles per square millimetre was eight times higher after scleral lens wear than at the beginning of wearing the lens for all groups. VA decreases in all groups after scleral lens wear (p < 0.001). All patients showed a statistical diminishing of contrast sensitivity after scleral lens wear (p < 0.05). A significant correlation was found for both turbidity parameters with distance VA but no correlation between turbidity and post-lens tear layer thickness at the beginning was found (p > 0.05). A strong correlation in all groups between the post-lens tear layer at the beginning and differences of tear layer thickness between two measures was also found (p < 0.05). Conclusion: The VA decrease during the scleral lens wearing, filled with preserved saline solution, was due to the increasing post-lens tear layer turbidity.
  • Publication
    Differences in corneo-scleral topographic profile between healthy and keratoconus corneas
    (Elsevier, 2019-02) Piñero, David P.; Martínez Abad, Antonio; Soto Negro, Roberto; Ruiz Fortes, Pedro; Pérez Cambrodí, Rafael J.; Ariza Gracia, Miguel Ángel; Carracedo Rodríguez, Juan Gonzalo
    Purpose: To evaluate the differences in corneo-scleral topographic profile between healthy and keratoconus eyes, and their potential diagnostic ability for keratoconus detection. Methods: Prospective comparative study including 21 keratoconic eyes (11 patients) and 88 healthy eyes (88 patients). In all cases, a complete eye exam was performed including an evaluation of the corneo-scleral profile. The diagnostic ability of corneo-scleral topographic parameters to detect keratoconus was evaluated using the receiver operating characteristic (ROC) curve. Results: A significant lower inferior tangent angle at limbus (ITA) was found in the keratoconic group compared to the control group (p = 0.024). Regarding sagittal heights, significant differences between groups were found in temporal sagittal height (TSH) for 11 mm (p = 0.040), 12 mm (p = 0.041) and 13 mm corneal chords (p = 0.040), difference between temporal and nasal sagittal heights (T-NSH) for 12 mm (p = 0.025) and 13 mm (p = 0.034), and maximum sagittal height (MaxSH) for 12 mm (p = 0.043), with higher values in keratoconus. In bilateral cases, these differences were not found when comparing with the least severe keratoconus eye. Statistical significance for the ROC curve was only found for ITA (p = 0.025), 12-mm (p = 0.048) and 13-mm TSH (p = 0.042), and 13-mm T-NSH (p = 0.037), with cutoff values associated to limited values of sensitivity and specificity. Conclusions: The corneo-scleral profile in keratoconus presents higher levels of asymmetry compared to healthy eyes, especially in eyes with moderate and advanced stages of the disease. The diagnostic accuracy of corneo-scleral topographic data alone for keratoconus detection is limited and must be used in conjunction with other clinical parameters.
  • Publication
    Anterior Corneal Curvature and Aberration Changes After Scleral Lens Wear in Keratoconus Patients With and Without Ring Segments
    (Wolters Kluwer, 2019-03) Serramito Blanco, Maria; Carpena Torres, Carlos; Carballo, Jesús; Piñero, David; Lipson, Michael; Carracedo, Gonzalo; Serramito Blanco, María; Carpena Torres, Carlos; Carballo Álvarez, Jesús; Carracedo Rodríguez, Juan Gonzalo
    Objective: To evaluate changes in the anterior corneal curvature and aberrometry after scleral contact lens wear in keratoconus (KC) subjects with and without intracorneal ring segments (ICRS). Methods: Twenty-six subjects diagnosed with keratoconus were selected to participate in the study. Subjects were divided into 2 groups, those with ICRS (KC-ICRS group) and those without ICRS (KC group). Subjects were instructed to wear 16.5-mm scleral lenses for 8 hours. Topographic and aberrometric parameters were evaluated before lens wear and immediately after lens removal. Anterior corneal curvature was evaluated at corneal diameters of 2, 4, 6, and 8 mm, and corneal aberrations were measured at 4-, 6-, and 8-mm pupil diameters. Results: The mean age of subjects was 36.95±8.95 years. In KC group, there was a statistically significant flattening of the central corneal curvature, from 6.98 to 7.09 mm (P<0.05). No changes were found in the central corneal curvature in the KC-ICRS group. The KC group showed anterior corneal curvature flattening, mainly in the nasal quadrant. The KC-ICRS group showed flattening primarily in the inferior hemisphere. In the KC group, spherical aberration for 6-mm pupil increased significantly. In the KC-ICRS group, changes in aberrations were significant for high-order root mean square at 4- and 6-mm pupil diameters (P<0.05), for oblique astigmatism for 4 mm and 6 mm, and for vertical coma for 4-mm pupil (P<0.05). Conclusion: Short-term scleral lens wear showed flattening of the anterior corneal surface in all subjects. In the KC group, the flattening was more pronounced in the nasal quadrant while changes were more pronounced inferiorly in KC-ICRS group.
  • Publication
    Diadenosine polyphosphates in the tears of aniridia patients
    (Wiley, 2015-07-23) Peral Cerda, Assumpta; Carracedo, Gonzalo; Pintor, Jesús; Peral Cerda, María Asunción; Carracedo Rodríguez, Juan Gonzalo; Pintor Just, Jesús Jerónimo
    Purpose: To quantify diadenosine polyphosphate levels in tears of congenital aniridia patients to estimate the ocular surface changes associated with congenital aniridia compared to normal individuals. Methods: Fifteen patients diagnosed with congenital aniridia and a control group of forty volunteers were studied. Tears were collected to quantify the levels of diadenosine polyphosphates Ap4A and Ap5A by high-performance liquid chromatography (H.P.L.C). Break-up time (BUT), corneal staining, McMon- nies questionnaire and the Schirmer I test were applied to both groups. Results: Dinucleotides in congenital aniridia patients were higher than in control subjects. For the congenital aniridia group, under 15 years old, the values were 0.77 0.01 lM and 0.17 0.02 lM for Ap4A and Ap5A, respectively. The group aged from 15 to 40 years old provided concentrations of 4.37 0.97 lM and 0.46 0.05 lM for Ap4A and Ap5A, the group over 40 gave concentrations of 11.17 5.53 lM and 0.68 0.17 lM for Ap4A and Ap5A. Dinucleotide concentrations increased with age, being statistically significant different among the three age groups (p < 0.05). Congenital aniridia patients showed a normal tear secretion and no dry eye McMonnies scores, except for the group over 40 years old. BUT values decreased and corneal staining increased with age and correlated with the levels of diadenosine polyphosphates (p < 0.05). Conclusions: The levels of dinucleotides in tears increase in aniridia patients compared with healthy subjects, and they seem to be related with the progression of corneal disorders in aniridia patients, both of which increase with ageing.