scholarly journals Combination of Violet Light Irradiation and Collagenase Treatments in a Rabbit Model of Keratoconus

2021 ◽  
Author(s):  
Hidenaga Kobashi ◽  
Takashi Yano ◽  
Kazuo Tsubota
Keyword(s):  
Elastic Modulus ◽  
Axial Length ◽  
Corneal Thickness ◽  
Rabbit Model ◽  
Corneal Astigmatism ◽  
Elastic Behaviour ◽  
Control Group ◽  
Violet Light ◽  
Collagenase Treatment ◽  
Significant Difference

Abstract Purpose: We evaluated the use of collagenase treatment to generate a rabbit model of keratoconus and the impact of violet light (VL) irradiation on the disease model in six Japanese White rabbits. Methods: After epithelial debridement, the collagenase group was treated with a collagenase type II solution for 30 min; the control group was treated with a solution without collagenase. Three rabbits also underwent VL irradiation (375 nm, irradiance 310 μW/cm2) for 3 hours daily for 7 days after topical collagenase application. Slit-lamp microscopy results, steep keratometry (Ks), corneal astigmatism, central corneal thickness, and axial length were examined before and after the procedure. The corneas were obtained on day 7 for biomechanical evaluation. Results: A significant increase in Ks and corneal astigmatism was observed in the collagenase and VL irradiation groups compared with the control group at day 7. No significant difference was found in the change in corneal thickness between the groups. The elastic modulus at 10% strain, but not at 3% and 5% strain, was significantly lower in the collagenase group than in the control group. There was no significant difference in the elastic modulus at each level of strain between the collagenase and VL irradiation groups. The average axial length at day 7 was significantly longer in the collagenase group than in the control group. Collagenase treatment induced a keratoconic model by steepening the keratometric and astigmatic values. There was no significant difference in the observed elastic behaviour of normal and ectatic corneas under physiologically relevant stress levels. Conclusion: VL irradiation did not cause regression of corneal steepening in collagenase-induced model during short-term observation.

scholarly journals Evaluation of Anterior Segment’s Structures in Tilted Disc Syndrome

2016 ◽  
Vol 2016 ◽  
pp. 1-4 ◽  
Author(s):  
Ercan Ozsoy ◽  
Abuzer Gunduz ◽  
Ersin Ersan Demirel ◽  
Tongabay Cumurcu
Keyword(s):  
Anterior Chamber ◽  
Axial Length ◽  
Corneal Thickness ◽  
Anterior Segment ◽  
Anterior Chamber Depth ◽  
Control Group ◽  
Tilted Disc Syndrome ◽  
Chamber Volume ◽  
Significant Difference ◽  
Tilted Disc

Purpose. To evaluate anterior segment’s structures by Pentacam in patients with tilted disc syndrome (TDS).Methods. Group 1 included forty-six eyes of forty-six patients who have the TDS. Group 2 including forty-six eyes of forty-six cases was the control group which was equal to the study group in age, gender, and refraction. A complete ophthalmic examination was performed in both groups. All cases were evaluated by Pentacam. The axial length (AL) of eyes was measured by ultrasound. Quantitative data obtained from these measurements were compared between two groups.Results. There was no statistically significant difference for age, gender, axial length, and spherical equivalent measurements between two groups (p=0.625,p=0.830,p=0.234, andp=0.850). There was a statistically significant difference for central corneal thickness (CCT), corneal volume (CV), anterior chamber angle (ACA), and pupil size measurements between two groups (p=0.001,p=0.0001,p=0.003, andp=0.001). Also, there was no statistically significant difference for anterior chamber depth (ACD), anterior chamber volume (ACV), and lens thickness (LT) measurements between two groups (p=0.130,p=0.910, andp=0.057).Conclusion. We determined that CCT was thinner, CV was less, and ACA was narrower in patients with TDS. There are some changes in the anterior segment of the eyes with tilted disc.

Axial Length and White to White Corneal Diameter in Eyes with Keratoconus

QJM ◽  
2021 ◽  
Vol 114 (Supplement_1) ◽  
Author(s):  
Omnia Talaat Abd elwahab ◽  
Dina Ezzat Mansour ◽  
Maged Maher Salib Roshdy ◽  
Ahmed Taha Ismail ◽  
Omnia Talaat Abd elwahab
Keyword(s):  
Axial Length ◽  
Corneal Thickness ◽  
Anterior Chamber Depth ◽  
Normal Group ◽  
Control Group ◽  
Spherical Equivalent ◽  
Lens Thickness ◽  
Significant Difference ◽  
The Mean ◽  
Corneal Diameter

Abstract Objective To study the axial length (AL) and white to white (WTW) corneal diameter in keratoconus (KC) eyes and compare them to normal eyes. Methods Sixty-three eyes of 53 patients were included in this cross-sectional observational study divided into KC group comprised of 28 eyes of 18 patients and control group comprised of 35 eyes of 35 patients based on clinical and tomographic findings. All subjects were examined using rotating Scheimpflug corneal tomography (Pentacam HR; Oculyzer II) for central corneal thickness (CCT), thinnest corneal thickness (TCT), keratometric values, anterior chamber depth (ACD) and lens thickness, and by optical biometry (IOLMaster 500) for axial length (AL) measurements. Vitreous cavity length (VCL) was calculated by subtracting the values of CCT, ACD (internal), and lens thickness from the AL. White to white (WTW) corneal diameter was measured using Placido-based tomography (Topolyzer VARIO). Results The mean age was 31.27±8.65 years(30.39 ± 9.31) in the KC group and .(31.74 ± 8.38) in the non KC group. The KC group included 28 eyes their mean spherical equivalent (SE) was -3.16 ± 2.42 and the control group 35 healthy eyes including 23 ametropic eyes with mean spherical equivalent (SE) (-3.95±4.50 D) and 12 emmetropic eyes with mean SE (-0.19±0.40 D). The mean VCL was significantly greater in normal eyes (17.45 ±1.34 mm) compared with KC (16.77±1.18 mm) (P = 0.037), while the mean ACD (internal) was significantly greater in KC eyes compared to normal (P = 0.020) and the lens thickness showed no statistically significant difference. The greater VCL in the normal group was compensated by the greater ACD in the KC group causing the total AL to have no statistically significant difference (normal eyes =24.44 ±1.38 mm and KC eyes= 24.21 ±1.31 mm) (P = 0.513). There was no statistically significant difference in the WTW corneal diameter between KC and normal eyes (11.81 ±0.35 mm in the normal group compared to 11.79 ±0.35 mm in the KC group) (P = 0.835). Conclusion VCL was significantly greater in normal eyes compared with those eyes with KC. AL and WTW showed no difference between the two groups.

scholarly journals Corneal Biomechanical Parameters and Central Corneal Thickness in Glaucoma Patients, Glaucoma Suspects, and a Healthy Population

2021 ◽  
Vol 10 (12) ◽  
pp. 2637
Author(s):  
Mª. Ángeles del Buey-Sayas ◽  
Elena Lanchares-Sancho ◽  
Pilar Campins-Falcó ◽  
María Dolores Pinazo-Durán ◽  
Cristina Peris-Martínez
Keyword(s):  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Mean Difference ◽  
The Other ◽  
Control Group ◽  
Healthy Population ◽  
Diagnostic Categories ◽  
Significant Difference ◽  
Biomechanical Parameters ◽  
The Mean

Purpose: To evaluate and compare corneal hysteresis (CH), corneal resistance factor (CRF), and central corneal thickness (CCT), measurements were taken between a healthy population (controls), patients diagnosed with glaucoma (DG), and glaucoma suspect patients due to ocular hypertension (OHT), family history of glaucoma (FHG), or glaucoma-like optic discs (GLD). Additionally, Goldmann-correlated intraocular pressure (IOPg) and corneal-compensated IOP (IOPcc) were compared between the different groups of patients. Methods: In this prospective analytical-observational study, a total of 1065 patients (one eye of each) were recruited to undergo Ocular Response Analyzer (ORA) testing, ultrasound pachymetry, and clinical examination. Corneal biomechanical parameters (CH, CRF), CCT, IOPg, and IOPcc were measured in the control group (n = 574) and the other groups: DG (n = 147), FHG (n = 78), GLD (n = 90), and OHT (n = 176). We performed a variance analysis (ANOVA) for all the dependent variables according to the different diagnostic categories with multiple comparisons to identify the differences between the diagnostic categories, deeming p < 0.05 as statistically significant. Results: The mean CH in the DG group (9.69 mmHg) was significantly lower compared to controls (10.75 mmHg; mean difference 1.05, p < 0.001), FHG (10.70 mmHg; mean difference 1.00, p < 0.05), GLD (10.63 mmHg; mean difference 0.93, p < 0.05) and OHT (10.54 mmHg; mean difference 0.84, p < 0.05). No glaucoma suspects (FHG, GLD, OHT groups) presented significant differences between themselves and the control group (p = 1.00). No statistically significant differences were found in the mean CRF between DG (11.18 mmHg) and the control group (10.75 mmHg; mean difference 0.42, p = 0.40). The FHG and OHT groups showed significantly higher mean CRF values (12.32 and 12.41 mmHg, respectively) than the DG group (11.18 mmHg), with mean differences of 1.13 (p < 0.05) and 1.22 (p < 0.001), respectively. No statistically significant differences were found in CCT in the analysis between DG (562 μ) and the other groups (control = 556 μ, FHG = 576 μ, GLD = 569 μ, OHT = 570 μ). The means of IOPg and IOPcc values were higher in the DG patient and suspect groups than in the control group, with statistically significant differences in all groups (p < 0.001). Conclusion: This study presents corneal biomechanical values (CH, CRF), CCT, IOPg, and IOPcc for diagnosed glaucoma patients, three suspected glaucoma groups, and a healthy population, using the ORA. Mean CH values were markedly lower in the DG group (diagnosed with glaucoma damage) compared to the other groups. No significant difference was found in CCT between the DG and control groups. Unexpectedly, CRF showed higher values in all groups than in the control group, but the difference was only statistically significant in the suspect groups (FHG, GLD, and OHT), not in the DG group.

scholarly journals Influence of the Thermal Treatment to Address a Better Osseointegration of Ti6Al4V Dental Implants: Histological and Histomorphometrical Study in a Rabbit Model

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Antonio Scarano ◽  
Ezio Crocetta ◽  
Alessandro Quaranta ◽  
Felice Lorusso
Keyword(s):  
Thermal Treatment ◽  
Dental Implants ◽  
Bone Healing ◽  
Rabbit Model ◽  
Titanium Implants ◽  
Control Group ◽  
Left Femur ◽  
Bone Response ◽  
First Choice ◽  
Significant Difference

Background. Pure titanium continues to be the first choice for dental implants and represents the gold standard for their biocompatibility and physical and mechanical characteristics, while the titanium alloy (Ti6Al4V) has good mechanical properties. The surface structure of the titanium oxide layer formation on the surface influences and improves the bone response around dental implants. Purpose. The purpose of this study is to evaluate the influence of a thermal treatment of Ti6Al4V implant surfaces and the bone healing response in a rabbit model. Methods. Altogether sixteen implants with same design were inserted into the distal femoral metaphysis. A screw (13 mm long, 4 mm in diameter) was inserted in an implant bed. Each rabbit received two implants, one in the left femur and one in the right femur. The samples were histologically and histomorphometrically evaluated at 8 weeks. Results. A statistically significant difference (p = 0.000034) was present histologically in the percentages of bone-implant contact (BIC) between the test group (BIC = 69.25±4.49%.) and control group (BIC = 56.25 ± 4.8%) by one-way analysis of variance (ANOVA). Significance was set at p ≤ 0.05. Conclusions. The outcome of the present study indicates a novel approach to improving bone healing around titanium implants.

scholarly journals Effect of Acute Increases in Intraocular Pressure on Corneal Pachymetry in Rabbit Eyes Treated with Timolol Maleate

2018 ◽  
Vol 12 (1) ◽  
pp. 314-321
Author(s):  
Cristina Sánchez-Barahona ◽  
Gema Bolívar ◽  
Dimitrios G. Mikropoulos ◽  
Anastasios G. Konstas ◽  
Miguel A. Teus
Keyword(s):  
Intraocular Pressure ◽  
Anterior Chamber ◽  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Rabbit Model ◽  
Controlled Study ◽  
Control Group ◽  
Study Group ◽  
Timolol Maleate

Objective: To evaluate in an in vivo rabbit model, the effect of topical timolol maleate therapy on the central corneal thickness response to acute intraocular pressure increases. Method: In this prospective and interventional controlled study, the central corneal thickness and intraocular pressure were measured in vivo in 12 rabbit eyes treated with topical timolol maleate for 1 month and in 12 controls at baseline, and after the intraocular pressure (measured by direct cannulation of the anterior chamber) was increased to 15 and 30 mmHg using a forced saline infusion into the anterior chamber. Results: There were no significant differences in the basal central corneal thickness values (control group, 373.2±12.9 µm; study group, 377.5±19.2 µm, p=0.5) or the central corneal thickness values when the intraocular pressure was increased to 15 mmHg (control group, 335.2±14.3 µm; study group, 330.0±32.1 µm, p=0.6) and to 30 mmHg (study group, 318.8±25.3 µm; control group, 329.8±21.0 µm, p=0.3). Conclusion: Rabbit corneas treated with topical timolol maleate for 1 month did not show a strain response to acute intraocular pressure increases that differed from control eyes. This is in contrast to a previous finding in which rabbit eyes treated with prostaglandin analogues had a greater decrease in central corneal thickness in response to a sudden intraocular pressure increase compared with untreated corneas.

Topical atropine in retarding myopia progression and axial length growth in children with myopia

2020 ◽  
Vol 13 (4) ◽  
pp. 111-114
Author(s):  
Abdur Rahman Mohammad Alam ◽  
Md. Sanwar Hossain ◽  
Md. Shafiqul Islam
Keyword(s):  
Axial Length ◽  
Control Group ◽  
Refractive Errors ◽  
Spherical Equivalent ◽  
Myopia Progression ◽  
Length Growth ◽  
Significant Difference ◽  
The Mean ◽  
And Control

This study was conducted to observe the effect of atropine in retarding myopia progression and axial length growth in 36 myopic children (atropine group, 24; control, 12). The initial spherical equivalent of the atropine group and control group was -3.0 ± 1.6 dioptre and -3.5 ± 1.6 dioptre respectively. At the 12th month in atropine group, it was -2.9 ± 2.6 dioptre and -4.6 ± 1.9 dioptre in the control group. The power of the atropine group reduced but rose in the control group after 12 months. There was a statistically significant difference in final refractive errors between the two groups (p<0.05). The initial axial length of the atropine group and control group was 24.3± 1.0 mm and 24.6 ± 1.1 mm respectively. In 12th month, the changes in axial length in the two groups was insignificant. However, the mean axial length progression at 12 months of the atropine group was -0.1 ± 0.1 mm and it was lower than the control group which was -0.2 ± 0.2 mm, and this was statistically significant (p<0.05). In conclusion, topical atropine (0.01%) retarded myopia progre-ssion and axial length growth in myopic children.    

scholarly journals Influence of Intra-Articular Administration of Trichostatin A on Autologous Osteochondral Transplantation in a Rabbit Model

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Huacheng Hou ◽  
Ke Zheng ◽  
Guanghu Wang ◽  
Shiro Ikegawa ◽  
Minghao Zheng ◽  
...  
Keyword(s):  
Articular Cartilage ◽  
Cartilage Repair ◽  
Trichostatin A ◽  
Interleukin 1 ◽  
Rabbit Model ◽  
Treated Group ◽  
Control Group ◽  
Osteochondral Transplantation ◽  
Autologous Osteochondral Transplantation ◽  
Significant Difference

Autologous osteochondral transplantation (AOT) is a method for articular cartilage repair. However, several disadvantages of this method have been reported, such as transplanted cartilage degeneration and the lack of a connection between the grafted and adjacent cartilage tissues. To evaluate the effect of intra-articular administration of trichostatin A (TSA) on AOT, we conducted a case control study in a rabbit model. International Cartilage Repair Society (ICRS) macroscopic scores, the modified O’Driscoll histology scores, and real-time PCR were utilized to evaluate the results. At 4 weeks, both macroscopic and histological assessments showed that there was no significant difference between the TSA and control groups. However, the mean macroscopic and histological scores for the TSA-treated group were significantly higher than the scores for the control group at 12 weeks. TSA was shown to directly reduce collagen type II (COL2), aggrecan, matrix metalloproteinase (MMP), and a disintegrin and metalloproteinase domain with thrombospondin motifs 5 (ADAMTS-5) expression and to simultaneously repress the upregulation of MMP-3, MMP-9, and MMP-13 levels induced by interleukin 1β(IL-1β) in chondrocytes. In conclusion, TSA protects AOT grafts from degeneration, which may provide a benefit in the repair of articular cartilage injury.

Use of N-butyl cyanoacrylate in nasal septoplasty: histopathological evaluation using rabbit nasal septum model

2010 ◽  
Vol 124 (7) ◽  
pp. 753-758 ◽  
Author(s):  
F Aksoy ◽  
F Yılmaz ◽  
Y S Yıldırım ◽  
K Gideroglu ◽  
Z Tatar
Keyword(s):  
Nasal Septum ◽  
Rabbit Model ◽  
Tissue Adhesive ◽  
Control Group ◽  
Open Approach ◽  
Septal Surgery ◽  
Nasal Floor ◽  
Significant Difference ◽  
Histopathological Evaluation ◽  
Haematoma Formation

AbstractObjectives:This study was designed to investigate the effects of the tissue adhesive N-butyl cyanoacrylate on nasal septal tissues after septal surgery in a rabbit model.Methods:Forty-two adult New Zealand rabbits were randomly divided into three groups (14 in each group): septoplasty alone, septoplasty plus N-butyl cyanoacrylate, and controls. The open approach was used to explore the nasal septum. After raising mucoperichondrial and mucoperiosteal flaps on both sides of the septum, the septum was detached from the nasal floor in the septoplasty alone and septoplasty plus N-butyl cyanoacrylate groups. In the septoplasty plus N-butyl cyanoacrylate group, the mucoperichondrial and mucoperiosteal flaps were fixed to the septum and the septum was fixed lateral to the nasal spine using N-butyl cyanoacrylate; in the septoplasty alone group, the septum was packed with Merocel. In the control group, no further septal surgery was performed after flap elevation. Animals were observed for bleeding and haematoma formation over the first 24 hours. Seven animals in each group were used to evaluate early histopathological effects on the septal tissues, at four weeks post-operatively; the other seven in each group were used to evaluate late effects, at 12 weeks.Results:Haematoma formation was observed in 10 animals in the septoplasty alone group, in four animals in the control group, and in only one animal in the septoplasty plus N-butyl cyanoacrylate group. The difference in haematoma incidence between the septoplasty alone and the septoplasty plus N-butyl cyanoacrylate groups was significant (p = 0.000). Histopathological evaluation revealed no significant difference between the groups as regards granulation tissue formation at week four versus week 12; however, there was a significant difference between the septoplasty plus N-butyl cyanoacrylate group and the control groups as regards inflammation at week 12 (p = 0.038). There was a significant difference between the septoplasty plus N-butyl cyanoacrylate group and the septoplasty alone group as regards the composition of the bone–cartilage junction zone at week four (p = 0.001). There was also a significant difference between the septoplasty plus N-butyl cyanoacrylate group and the control group as regards the cellular structure of new cartilage formation at week 12 (p = 0.004).Conclusions:In this rabbit septoplasty model, N-butyl cyanoacrylate appeared to be an effective nasal tissue adhesive, with a low complication rate.

Marginal Adaptation of Direct Class II Composite Restorations with Different Cavity Liners

2013 ◽  
Vol 38 (6) ◽  
pp. E210-E220 ◽  
Author(s):  
R Pecie ◽  
I Onisor ◽  
I Krejci ◽  
T Bortolotto
Keyword(s):  
Elastic Modulus ◽  
Class Ii ◽  
Control Group ◽  
Shrinkage Stress ◽  
Marginal Adaptation ◽  
Composite Restorations ◽  
Significant Difference ◽  
Before And After ◽  
Group A ◽  
Group D

SUMMARY The aim of this study was to evaluate how cavity linings with different elastic modulus can influence the marginal adaptation (MA) of Class II composite restorations before and after thermo-mechanical loading. Materials and Methods: Forty Class II cavities with margins extending 1 mm below the cement-enamel junction were prepared in extracted human third molars. In each group except the control group, a lining material of 1-mm thickness was applied to the bottom of the cavity and polymerized before placing the resin composite Herculite XRV Ultra (group A: control; group B: Premise Flowable lining; group C: Herculite XRV Ultra lining; and group D: Optibond FL lining). MA was evaluated (with a scanning electron microscope) before and after loading (200,000 loading cycles). Statistical analysis was done using the Shapiro-Wilks test, the analysis of variance test, and Duncan post hoc test at p&lt;0.05. Results: Before loading, the percentages of continuous margins in dentin were superior (p&lt;0.05) for groups C and D (71.1% and 87.2%, respectively) compared to groups A and B (55.7% and 48.3%, respectively). After loading, group D (79.8%) was statistically superior in dentin compared to all of the other groups (43.6%, 35.9%, and 54.4%, respectively). In occlusal enamel, no significant difference was found between groups. The percentage of enamel fractures and the percentage of noncontinuous margins in proximal enamel were high, with no significant difference between liners. It can be concluded that for the materials used in this study, a 1-mm-thick lining with an extremely low elastic modulus (2-3 GPa) could redistribute shrinkage stress. The use of a flowable composite did not significantly improve MA.

The Evaluation of Central Corneal Thickness and Intraocular Pressure in Conjunction with Tear IGF-1 Levels in Patients with Acromegaly

2017 ◽  
Vol 27 (5) ◽  
pp. 531-534
Author(s):  
Emrah Kan ◽  
Elif K. Kan ◽  
Ali Okuyucu
Keyword(s):  
Intraocular Pressure ◽  
Central Corneal Thickness ◽  
Disease Duration ◽  
Corneal Thickness ◽  
Disease Status ◽  
Control Group ◽  
Significant Difference ◽  
Igf I ◽  
Duration Of Disease ◽  
And Control

Purpose To compare the central corneal thickness (CCT), intraocular pressure (IOP), and tear insulin-like growth factor 1 (IGF-1) levels between patients with acromegaly and a control group and to evaluate the possible effect of tear IGF-1 and duration of the disease on CCT and IOP. Methods We included 31 patients with acromegaly (study group) and 40 age- and sex-matched controls in the study. Patients with acromegaly were divided into 2 subgroups based on disease status (active/inactive). All participants underwent complete ophthalmologic evaluation including CCT and IOP values. Basal tear samples were collected from both groups and tear IGF-1 levels were measured. The CCT, IOP, and tear IGF-1 levels were compared between groups and subgroups and the association between tear IGF-I levels and ocular parameters (CCT, IOP) and disease duration were also evaluated. Results Central corneal thickness, IOP, and tear IGF-1 levels did not show a significant difference between study and control groups. We also did not find a significant difference in terms of CCT, IOP, or tear IGF-1 levels between subgroups of patients. Correlation analysis did not show an association between the duration of disease and tear IGF-1 levels with CCT or IOP. Conclusions There was no significant difference in tear IGF-1 levels between patients with acromegaly and controls. Additionally, there was no correlation between disease duration and tear IGF-1 levels with CCT or IOP levels. This lack of association may suggest that tear IGF-1 levels might not have an effect on CCT or IOP findings in patients with acromegaly.

Sign in / Sign up

Export Citation Format

Share Document