ABSTRACT
ABSTRACT Purpose: This study aimed to examine the effects of unilateral corneal collagen cross-linking treatment on visual acuity and the topographic findings of the fellow untreated eye of patients who had bilateral progressive keratoconus. Methods: Patients with progressive keratoconus who underwent cross-linking treatment were screened retrospectively. A total of 188 untreated eyes of 188 patients whose eyes were treated unilaterally with either standard or accelerated cross-linking and refused cross-linking procedure for the fellow eye were included. Visual acuity and topographic findings of the fellow untreated eyes were obtained preoperatively and postoperatively at the 1st, 3rd, 6th, 12th, 24th, 30th, and 36th months. Results: The change over time of variables examined was similar in the untreated eyes of patients who received standard and accelerated cross-linking methods (p>0.05). At the 12th month, 136 (95.8%) untreated eyes were stable according to progression criteria. Only 4 (8%) eyes were progressive at the 24th month. No progression was observed in any of the 16 patients with a 36-month follow up. Conclusions: The results showed that the fellow untreated eyes of patients with bilateral progressive keratoconus did not have significant progression rates after unilateral cross-linking treatment.
RESUMO Objetivo: Examinar os efeitos do tratamento de reticulação unilateral do colágeno corneano na acuidade visual e os achados topográficos em olhos não tratados de pacientes com ceratocone progressivo bilateral. Métodos: Foram rastreados retrospectivamente pacientes com ceratocone progressivo submetidos a tratamento de reticulação. Foram incluídos no estudo 188 olhos não tratados de 188 pacientes tratado unilateralmente com reticulação padrão ou acelerada e que recusaram o procedimento de reticulação no outro olho. A acuidade visual e os achados topográficos dos olhos não tratados foram obtidos no pré- e pós-operatório no 1º, 3º, 6º, 12º, 24º, 30º e 36º mês. Resultados: As alterações ao longo do tempo foram semelhantes para as variáveis examinadas nos olhos não tratados de pacientes tratados com métodos de reticulação padrão e acelerado (p>0,05). No 12º mês, 136 olhos não tratados (95,8%) estavam estáveis, de acordo com os critérios de progressão. Apenas quatro olhos (8%) mostraram progressão no 24º mês. Nenhuma progressão foi observada nos 16 pacientes que tiveram um acompanhamento de 36 meses. Conclusões: O estudo mostrou que os olhos não tratados de pacientes com ceratocone progressivo bilateral não apresentaram taxas de progressão significativas após o tratamento unilateral com reticulação.
ABSTRACT
AIM:To evaluate corrective effect and stability of corneal morphology in patients with moderate to high myopia after 2a treatment of femtosecond laser assisted laser in situ keratomileusis(FS-LASIK)Xtra.METHODS:Retrospective case-control study. A total of 30 cases(58 eyes)Patients with moderate to high myopia combined with astigmatism who planned to undergo refractive surgery in our hospital from August 2019 to August 2020 were included, and different types of surgery were performed respectively based on the relevant index of keratoconus screening in the preoperative corneal topography. They were divided into FS-LASIK group and Xtra group, with 15 cases(29 eyes)in each group. Uncorrected visual acuity(UCVA), best corrected visual acuity(BCVA), spherical equivalent(SE)and the corneal curvature of the anterior and posterior surfaces of different diameters(3, 5 and 7 mm)measured by Sirius three-dimensional corneal topography were observed preoperatively and 3 mo, 1 and 2 a postoperatively.RESULTS: The UCVA of the two groups of patients at different time points after surgery was significantly increased compared with preoperatively(both P<0.01), and there was no difference in UCVA and SE between the two groups(P>0.05). After 2 a postoperatively, residual astigmatism was -0.25-0 D in 25 eyes(86%)of the FS-LASIK Xtra group and 24 eyes(83%)of the FS-LASIK group. The actual corrected SE and expected corrected SE of both groups were positively correlated(both P<0.05). There were differences in corneal curvature on the surface of different diameter areas(3, 5, and 7 mm)between the two groups at 3 mo, 1, and 2 a postoperatively compared with preoperatively. After 1 and 2 a postoperatively, the corneal posterior surface curvature of the FS-LASIK Xtra group with corneal diameter of 3 and 5 mm was higher than that of the FS-LASIK group(P<0.05).CONCLUSIONS:FS-LASIK Xtra has good safety, efficacy and predictability in correcting patients with moderate to high myopia.
ABSTRACT
Purpose: To determine the efficacy and safety of pediatric accelerated cross linking (CXL). Methods: A prospective study on progressive keratoconus (KC) cases under ?18 years of age. Sixty four eyes of thirty nine cases underwent epithelium?off accelerated CXL protocol. Visual acuity (VA), slit?lamp examination, refraction, pentacam reading of keratometry (K), corneal thickness, and thinnest location pachymetry were noted. Cases were followed up on days 1, 5, and at 1st, 3rd, 6th, and 12th?month post procedure. Results: Statistically, significant improvement of the mean aided VA, K, and mean corneal astigmatism (p < 0.0001) was noted. Mean Kmax reading reduced from 55.5 ± 5.64 (47.4–70.4) diopter (D) preoperatively to 54.41 ± 5.51 (46–68.3) D at 12 months postaccelerated CXL. Two cases had progression. Complications encountered were sterile infiltrate and persistent haze. Conclusion: Accelerated CXL is effective and efficacious in pediatric KC.
ABSTRACT
Purpose: To investigate the effects of riboflavin and/or ultraviolet?A (UV?A) irradiation on the cell viability of ex?vivo?cultured rat limbal stem cells (LSCs). Methods: LSCs of male Wistar rats (N = 12 eyes) were cultured, and immunofluorescence staining was performed to evaluate them. After characterization, these cells were assigned to four groups of control (C), a group that was exposed to UV?A radiation (UV), a group that was treated with riboflavin (R), and a group that cotreated with both UV?A and riboflavin (UV+R). To determine the cell viability of LSCs, these cells were subjected to MTT assay on days 1, 3, and 7 after exposure to UV?A and/or riboflavin. The duration of exposure to UV?A and riboflavin was similar to levels used during the conventional corneal collagen cross?linking procedure. Results: Compared with the viable cells in the control group, there was a significant decrease (P < 0.0001) in the number of LSCs in the UV group during all study days. In the R group, the level of viable LSCs was as same as the level of viable LSCs in the C group. Combined treatment with UV?A plus riboflavin significantly decreased the survival of LSCs on days 1 and 3 (P < 0.0001, P < 0.001, respectively) compared with the control group. Interestingly, in the UV+R group, the photosensitizing effect of riboflavin significantly decreased the cytotoxic effect of UV irradiation 7 days after exposure. Conclusion: These results suggest that the administered UV energy in the presence or absence of riboflavin can damage LSCs. Likewise, riboflavin could decrease the toxic effect of UVA on LSCs
ABSTRACT
This article reports a novel surgical technique of partial-thickness compression sutures without descemetopexy with air or gas for the management of acute hydrops in keratoconus. Two patients presented with localized corneal edema with a Descemet membrane (DM) tear in the left eye. Tomography of the right eye revealed localized steepening with increased maximum keratometry and decreased central pachymetry. They were diagnosed with keratoconus in the right eye and acute corneal hydrops (ACH) in the left eye. Compression sutures were passed through the stroma without touching the DM. The anterior chamber was not entered at all at any point during the surgery. Resolution of edema was noted intraoperatively itself. Further resolution of edema was noted from the first postoperative day which markedly reduced within the first week. A corneal scar with no edema was seen at six weeks. In both the patients, vision at presentation was counting fingers close to face which improved to 20/60 and 20/50, respectively, at the last visit.
ABSTRACT
Objective:To explore the association of bone resorption marker β carboxyterminal peptide of collagen Ⅰ (β-CTX) with hypercalcemia in patients with Graves′ disease (GD).Methods:287 patients with GD who were hospitalized in the endocrinology department of Fuyang People′s Hospital from January 2021 to December 2021 were divided into control group ( n=251) and hypercalcemia group ( n=36) according to the corrected blood calcium level. The clinical data and serum β-CTX level of the two groups were compared. Logistic regression model was used to analyze the risk factors of hypercalcemia in GD patients. Pearson correlation was used to analyze the correlation between serum β-CTX level and other indexes. Results:Of the 287 GD patients, 36 were diagnosed as hypercalcemia, and the incidence of hypercalcemia was 12.54%. The levels of free triiodothyronine (FT3), free thyroxine (FT4), blood phosphorus (P) and β-CTX in hypercalcemia group were higher than those in control group, and the total parathyroid hormone (iPTH) in hypercalcemia group were lower than those in control group (all P<0.05). Multivariate Logistic regression analysis showed that FT3 ( OR=1.283, 95% CI: 1.049-1.570, P<0.05), iPTH ( OR=0.924, 95% CI: 0.863-0.989, P<0.05), β-CTX ( OR=2.488, 95% CI: 1.193-5.189, P<0.05) were the influencing factors for hypercalcemia in GD patients. Pearson correlation analysis showed that β-CTX was positively correlated with FT3, FT4, blood calcium, P, alkaline phosphatase (ALP), total procollagen type I amino end terminal peptide (PINP), N-bone-gamma-carboxyglutamic-acid-containing proteins (N-MID) and 25(OH)D, and negatively correlated with iPTH (all P<0.05). Conclusions:β-CTX is highly expressed in the serum of GD patients with hypercalcemia, which is a risk factor for the occurrence of hypercalcemia in GD patients.
ABSTRACT
Objective:To investigate the efficacy and safety of accelerated epithelium-off corneal collagen cross-linking (CXL) in the treatment of corneal ectasia after keratorefractive surgery.Methods:An observational case series study was performed.Twelve patients (22 eyes) diagnosed with corneal ectasia after keratorefractive surgery in the First Affiliated Hospital of Army Medical University were enrolled from January 2016 to December 2018.All the patients received accelerated epithelium-off CXL and were followed up for 12 months.Before and 1 week, 1, 3, 6, and 12 months after the operation, the uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA) converted to the logarithm of the minimum angle of resolution (LogMAR) unit were measured.The sphericity, cylindricity, and spherical equivalent were examined by Topcon auto refractor.The maximum keratometry (Kmax) of the front surface, mean keratometry (Km) of the front surface, Km of the back surface, symmetry index of front surface (SIf), symmetry index of back surface (SIb), thinnest corneal thickness (TCT), total aberrations, total high-order aberrations, coma aberration, trefoil aberration and spherical aberration were detected by the Sirius analyzer.The depth of corneal demarcation lines was determined by optical coherence tomography.The intraocular pressure was measured by the non-contact tonometry.The corneal endothelial cell density was assayed by the endothelial cell densitometry.The inflammatory reaction and haze were observed with a slit lamp at different time points after surgery.This study adhered to the Declaration of Helsinki.The study protocol was approved by the First Affiliated Hospital of Army Medical University (No.KY2020063). Written informed consent was obtained from each patient before entering the cohort.Results:Among the 22 eyes of 12 cases, 3 eyes of 2 cases (13.64%) underwent small incision lenticule extraction, and 19 eyes of 10 cases (86.36%) underwent excimer laser in situ keratomileusis.The UCVA (LogMAR), BCVA (LogMAR), cylindricity and spherical equivalent before the operation were 0.61±0.42, 0.24±0.23, (-2.83±2.39)D, (-3.60±2.66)D, which were significantly worse than 0.45±0.31, 0.12±0.15, (-2.11±1.67)D, (-3.12±2.31)D at 12 months after the operation ( t=4.054, 4.956, -3.728, -2.742; all at P<0.05). The front surface Kmax, front surface Km and SIf at 12 months after the operation were (48.37±5.80), (41.49±3.04), (5.36±4.07)D, which were significantly lower than (49.61±5.97), (41.66±2.97), (5.85±4.18)D before the operation ( t=5.949, 2.278, 2.719; all at P<0.05). There was no significant difference in sphericity, Km of the back surface, SIb, TCT, total aberrations, total high-order aberrations, coma aberration, trefoil aberration, spherical aberration, intraocular pressure and endothelial cell density between before and 12 months after the operation (all at P>0.05). Grade 0.5-2 haze occurred in 8 eyes of 4 patients one month postoperatively.After administration of prednisolone acetate eye drops, haze decreased or disappeared 3 months postoperatively, with UCVA and BCVA unchanged.A corneal demarcation line with a depth of (285.40±51.61)μm was found in 11 eyes of 6 cases at 1 month after operation. Conclusions:Accelerated epithelium-off CXL can significantly improve visual acuity, reduce corneal astigmatism and corneal curvature, as well as effectively prevent the progress of corneal ectasia.
ABSTRACT
Objective:To compare the characteristics of corneal stromal demarcation line after different surgical methods of riboflavin/ultraviolet A corneal collagen cross-linking (CXL) in early keratoconus, and analyze the influence of the demarcation line on the cross-linking effect.Methods:A non-randomized controlled clinical study was conducted.Sixty-nine eyes of 69 patients treated with riboflavin/ultraviolet A CXL in the Eye Hospital of Shandong First Medical University from May 2019 to February 2021 were included.According to the cross-linking methods, the patients were divided into epithelium-on treatment group (21 eyes) and epithelium-off treatment group (48 eyes). There were 25 eyes in 5.4 J energy group and 44 eyes in 7.2 J energy group.The morphology and changes of corneal stromal cross-linking reaction (corneal stromal demarcation line) were observed at 2 weeks, 1, 3 and 4 months after operation.Changes in the thinnest corneal thickness (TCT), uncorrected visual acuity (UCVA, LogMAR), best corrected visual acuity (BCVA, LogMAR) and corneal maximum curvature (Kmax) were recorded.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Eye Hospital of Shandong First Medical University (No.2019.05). Written informed consent was obtained from each subject.Results:Of the 69 eyes after operation, 44 eyes (63.77%) had demarcation lines, and 25 eyes (36.23%) had no demarcation lines.The occurrence rate of demarcation lines in the epithelium-on treatment group was 79.17%(38/48), which was significantly higher than 28.57%(6/21) in the epithelium-off treatment group ( χ2=16.186, P<0.01). The occurrence rate of demarcation line in 5.4 J energy group was 72.00%(18/25), and the 7.2 J energy group was 56.80%(25/44), with no significant difference ( χ2=1.565, P=0.302). Slit lamp microscopy and anterior segment-optical coherence tomography showed that the demarcation line appeared at 1-2 weeks after operation, gradually converged and strengthened after 1 month, turned diffuse, blurred and faded by degrees after 2-3 months, and basically disappeared after 4 months.The depth of the demarcation line reached 141-423 μm, with an average depth of (263.44±84.22)μm.Scanning laser confocal microscopy showed that corneal stromal cells were activated and light reflection was enhanced after CXL.Collagen fibers extended vertically and horizontally, crisscrossed, and were in a reticular arrangement.The TCT decreased from preoperative (458.69±38.28)μm to (443.86±36.54)μm at 4 months after operation, showing a statistically significant difference ( t=6.705, P<0.001). There was no significant difference in the TCT reduction between groups with and without demarcation lines ( t=1.684, P=0.100). At 4 months postoperatively, the UCVA of all eyes increased from preoperative 0.74±0.37 to 0.69±0.38, and the difference was statistically significant ( t=2.109, P=0.039). There was no significant difference in BCVA between before and after operation ( t=1.006, P=0.319). There was no significant difference in change of UCVA and BCVA between groups with and without demarcation lines ( t=0.065, P=0.949; t=0.346, P=0.730). There was no significant difference in Kmax in all patients between before and after operation ( t=0.050, P=0.950). There was no significant difference in the Kmax change between groups with and without demarcation lines ( t=-0.739, P=0.464). The change in TCT in the epithelium-off treatment group was significantly greater than that in the epithelium-on treatment group ( t=2.815, P=0.008). There was no significant difference in UCVA, BCVA and Kmax changes between epithelium-on and epithelium-off treatment groups (all at P>0.05). There was no obvious corneal scarring, infectious keratitis, corneal endothelial decompensation or other complications. Conclusions:The demarcation line after CXL may be a sign of the depth of cross-linking reaction, which is more prone to occur after the epithelium-off operation method.Both the epithelium-on and epithelium-off operation methods have similar therapeutic effects.Demarcation line after different cross-linking methods has no significant influence on the cross-linking effect in keratoconus.
ABSTRACT
@#Proanthocyanidin (PA), as a kind of natural plant polyphenol, have a variety of biological functions, such as promoting remineralization, inducing collagen cross-linking, inhibiting protease activity and inhibiting bacteria. Therefore, PA could be broadly used in the clinical application of treatment and repair of deep caries in the future; for example, PA could promote dentin remineralization, improve resin-dentin bonding durability and improve the dentin acid erosion effect. This application potential of PA arises from several features, firstly, PA can not only promote dentin remineralization on its own or with other remineralizers but also exhibits antibacterial effects, which can inhibit acid production while reducing the formation of cariogenic pathogens and their biofilms. Based on the above features, PA can reduce the incidence of caries disease; thus, PA improves deep caries and long-term effects after treatment. In addition, PA added to adhesives or etch agents can improve the etching and bonding effect of dentin by inducing collagen cross-linking and inhibiting protease activity, thus achieving the ultimate goal of improving the bonding performance of deep caries. This paper summarizes recent progress of research on PA for the treatment and repair of deep caries, including the promotion of dentin remineralization and antibacterial activity as well as the improvement in dentin bonding and acid etching effect, to provide a more comprehensive reference for treating and restoring deep caries in clinical practice.
ABSTRACT
AIM: To observe the epithelial remodeling of femtosecond laser-assisted stromal lenticule addition keratoplasty combined with corneal collagen cross-linking(SLAK-CXL)in patients with progressive keratoconus, investigate the remodeling rules of corneal epithelial and influencing factors, and provide clinical data for further refractive correction.METHODS: Retrospective and observational study. A total of 28 keratoconus patients(29 eyes)who received SLAK-CXL from September 2020 to October 2021 were included. Preoperative and postoperative visual acuity, intraocular pressure(IOP), diopter, keratometry and corneal epithelial thickness(CET)were recorded. The trend of CET change was observed. The factors affecting CET were analyzed according to the thickness and depth of the lenticule.RESULTS: Flattest meridian keratometry(Kf)and steepest meridian keratometry(Ks)at 1mo postoperatively were significantly larger than those preoperatively(P<0.05). The thinnest corneal thickness(TCT)at 1, 2, 6mo and 1a postoperatively were significantly larger than preoperative(P<0.05). The CET changed with time, with the central CET showing a larger variation tendency. The CET of superior, superior nasal, nasal, superior temporal in paracentral area were thinned, the CET of superior, temporal, superior temporal in midperipheral area were thinned, while the CET of superior nasal was thickened in peripheral area at 1, 2, 6mo and 1a postoperatively. The variation of CET was not correlated with the thickness or depth of lenticule at 1a postoperatively(P>0.05).CONCLUSIONS: It is firstly found that the corneal morphology has changed after SLAK-CXL. CET decreases and then increases and then decreases again. At 1a postoperatively, the CET of the central and paracentral areas is thinner, while the CET of the midperipheral and peripheral areas is thicker. The degree of epithelial remodeling is not correlated with lenticule thickness or depth.
ABSTRACT
AIM: To investigate the efficacy of epithelial-off accelerated corneal cross-linking(CXL)in the treatment of advanced keratoconus.METHODS: A retrospective study was performed on data collected from 32 patients(43 eyes)with advanced keratoconus who underwent epithelial-off accelerated CXL at Ningxia Eye Hospital from April 2020 to December 2021. Slit-lamp, intraocular pressure, uncorrected visual acuity(UCVA), corrected visual acuity, specular microscope, Pentacam and Corvis ST were tested before and at 1, 3 and 6mo after surgery. Preoperative and postoperative corneal condition, UCVA, best corrected visual acuity(BCVA)and the values of corneal endothelial, maximum keratometry(Kmax), thinnest corneal thickness(TCT), anterior and posterior surfaces of the cornea K1, K2, biomechanically corrected intraocular pressure(bIOP), applanation time 1(A1T), applanation length 1(A1L), applanation velocity 1(A1V), applanation time 2(A2T), applanation length 2(A2L), applanation velocity 2(A2V), highest concavity deformation amplitude(HCDA), radius at highest curvature(HCR), highest concavity peak distance(HCPD)and stiffness parameter at first applanation(SP-A1)were recorded.RESULTS: There were differences between UCVA(LogMAR; 1.06±0.49, 0.78±0.39)and BCVA(LogMAR; 0.48±0.34, 0.38±0.29)before and at 6mo after surgery(P<0.05), but there were no differences in corneal endothelial cells(2917.39±288.38 vs. 2959.19±336.27 cells/mm2, P=0.477). There were differences among Kmax, TCT, anterior surface K1 and K2 and posterior surface K1 before and after surgery(P<0.05), and all increased at 1mo after surgery then returned to preoperative level at 3mo after surgery, while there was no difference in the posterior K2. Furthermore, there were statistical significance in A1T, HCPD and SP-A1 before and after surgery(P<0.05), while there were no statistical significance in A1L, A1V,A2T, A2L, A2V, HCDA, HCR and bIOP(P>0.05).CONCLUSION: Epithelial-off accelerated CXL can prevent the progression of keratoconus within half year after surgery, and it has certain safety.
ABSTRACT
In 2004, it was the first time that Wollensak and Spoerl had applied physical and chemical cross-linking methods to scleral tissue. They found that the biomechanical strength of cross-linked sclera, induced by riboflavin/ultraviolet A, glyceraldehyde and glutaraldehyde, could be improved and proposed that scleral collagen cross-linking is expected to be a new method for the treatment of pathologic myopia. In recent years, a series of explorations have been made on the effectiveness and adverse reactions of physical and chemical cross-linking in the prevention and treatment of pathologic myopia, including the establishment of various animal models and different myopia modeling methods, the improvement of cross-linking methods, the amelioration of the measurement of biomechanical strength of scleral tissue and the attention of biological parameters such as the thickness of retinal nerve fiber layer and the amplitude of electroretinogram in vivo. Genipin-crosslinking of the scleral collagen combined with posterior scleral contraction/reinforcement has been applied to clinical research. This review summarizes physical cross-linking and the genipin-crosslinking of scleral collagen to explore the effectiveness and safety of the methods in the prevention and treatment of the pathologic myopia.
ABSTRACT
ABSTRACT Introduction: A weak venous wall is one of the major reasons contributing to vein graft failure after coronary artery bypass grafting (CABG). We investigated whether adventitial collagen cross-linking by glutaraldehyde reinforces venous wall, preserving the endothelium of veins during high-pressure distention. Methods: Human saphenous veins (SVs) were collected from 40 patients undergoing CABG, and adventitia cross-linking was performed with 0.3% glutaraldehyde for five minutes. The cross-linked SVs were accessed by biodegradation assay, immunofluorescent staining, and tensile test. Native SVs and cross-linked SVs from another 20 patients received the 200 mmHg pressure distention for two minutes. Pressure-induced injury of SVs were accessed by immunohistochemistry and electron microscopy. Results: Time to digestion was 97±13 minutes for native SVs and 720±0 minutes for cross-linked SVs (P<0.05). After adventitial cross-linking, the collagen I fibres of the vein remarkably presented with compact and nonporous arrangement. In the high-stretch region (stretch ratio 1.4-1.8), the Young's elastic modulus of stress-stretch ratio curve in cross-linked SVs was larger than that in native SVs (13.88 vs. 5.83, P<0.05). The cross-linked SVs had a lower extent of endothelial denudation without fibre fracture during high-pressure distension than native SVs. Comparing with the non-cross-linked SVs, the percentage of endothelial nitric oxide synthase staining length on the endothelium of cross-linked SVs was significantly preserved after high-pressure distension (85.2% vs. 64.7%, P<0.05). Conclusion: Adventitial collagen cross-linking by glutaraldehyde reinforced venous wall by increasing stiffness and decreasing extensibility of SVs and mitigated the endothelial damage under high-pressure distension.
ABSTRACT
Purpose: To monitor the changes in the ABCD grading system during a one?year follow?up after a corneal cross?linking (CXL) procedure. Methods: This prospective study included 30 eyes of 25 patients with keratoconus, who received the CXL treatment. The patients with a history of ocular trauma or surgery and other corneal pathology were excluded from the study. The patients were examined at the baseline visit and followed up at 3, 6, and 12 months after the CXL. All the patients underwent a standard CXL procedure with visual acuity and Scheimpflug tomography testing at each visit. The corneal parameters and ABCD grading were monitored throughout the follow?up period. Results: There were no significant changes of parameter A and anterior radius curvature (ARC) in the ABCD grading system. Parameters B and D showed progression postoperatively, with an improvement of parameter D on the final visit. Parameter C showed a statistically significant increase at all three post?CXL visits, but a constant gradual decrease in the value over time. Conclusion: The ABCD grading system can be very useful in monitoring the progression of keratoconus (KC), but it can also help in monitoring the efficacy of corneal cross?linking. The anterior surface parameters in the ABCD grading system did not show progression in the post?CXL period, and parameters C and D showed improvement and stability a year after the procedure.
ABSTRACT
Purpose: To find the intraocular lens (IOL) power calculation changes before and after isotonic collagen cross?linking (CXL) in keratoconus patients. Methods: Thirty?five eyes of 25 patients who underwent isotonic CXL were included. The cases included conventional CXL (n = 16), accelerated CXL (n = 7), contact lens?assisted CXL (CACXL) (n = 9), accelerated CACXL (n = 3). All underwent ocular biometry (IOL master), corneal topography (Orbscan II), and simulated keratometry (Orbscan II) preoperatively and 1?year post CXL. Change in best?corrected visual acuity (BCVA), axial length (AL), simulated keratometry (Sim K), anterior chamber depth (ACD), and IOL power were analyzed in the overall data and then grouped based on flattening (Group A) and no flattening (Group B) of Sim K value post CXL procedure. Results: For the overall data, there was no significant change in IOL power (P = 0.05) at the end of 1 year, BCVA showed a significant increase (P < 0.01), and Sim K reading showed a statistically significant flattening (P = 0.001); ACD and AL showed insignificant change. In intergroup comparison, there was no statistically significant change in IOL power. However, in Group A, a significant change in BCVA and Sim K values was observed. In both groups (Group A and Group B), IOL power was found to be negatively correlated with AL and Sim K values. Conclusion: Isotonic CXL did not affect IOL power calculation at the end of 1 year. However, significant change in BCVA and sim K reading was noted
ABSTRACT
@#AIM:To investigate the clinical efficacy and safety of trans-epithelial accelerated corneal collagen cross-linking in the treatment of progressive keratoconus.METHODS: A prospective before-after self-control study. A total of 47 eyes of 37 patients with progressive keratoconus who underwent trans-epithelial accelerated corneal collagen cross-linking in our hospital from August 2016 to November 2019 were collected. Uncorrected visual acuity(UCVA), best corrected visual acuity(BCVA), refractive status, corneal transparency, maximum keratometry value of the anterior corneal surface, thinnest corneal thickness, corneal endothelial cell counts and intraocular pressure(IOP)were analysed preoperatively and at 1, 3, 6 and 12mo postoperative.RESULTS: UCVA of patients 1, 3, 6 and 12mo after surgery was higher than that before surgery, but there was no difference(<i>F</i>=1.372, <i>P</i>=0.261). BCVA at 1, 3, 6 and 12mo after surgery was higher than that before surgery, the difference was statistically significant(<i>F</i>=3.308, <i>P</i>=0.019). There were no differences in the spherical and cylindrical power, Kmax and thickness of the thinnest point of cornea at 1, 3, 6 and 12mo postoperatively compared with those before surgery(<i>F</i>=0.293, 1.378, 2.448, 1.970; <i>P</i>=0.881, 0.258, 0.061, 0.116). There was no difference in corneal endothelial cell counts between 1mo after surgery and before surgery(<i>t</i>=1.156, <i>P</i>=0.25). There was no difference in IOP at all postoperative time points compared with that before surgery(<i>F</i>=1.221, <i>P</i>=0.321). The corneal Haze(grade 1-2)appeared in 7 eyes after surgery, and subsided in 5 eyes from 3-6mo after surgery, and the corneal transparency recovered. The corneal nebula remained in 1 eye, and the corneal central stroma linear opacity existed in 1 eye, but the visual acuity of both eyes was not affected.CONCLUSION: Trans-epithelial accelerated corneal collagen cross-linking can significantly improve BCVA, stabilize refractive status, corneal morphology and thickness, prevent or delay the progression of keratoconus, and enable patients to obtain better visual function. At the same time, the operation time is short, postoperative complications are less, and the operation has good safety.
ABSTRACT
Embolotherapy is a common method for clinical intervention in the treatment of diseases including aneurysms, arteriovenous malformations and solid tumors, and embolic agents are a decisive factor affecting the effect of embolization. Although various embolic agents like coils, microspheres, and Onyx have been used clinically, there are still some treatment limitations: such as weak blood vessel penetration, easy to aggregate, poor mechanical properties, adhesion to catheters, and the need for toxic solvents (e.g. dimethyl sulfoxide). In recent years, a number of studies have found that in situ hydrogels have good application prospects in the field of vascular embolization. When low viscosity precursor solution is injected into the targeted blood vessel via microcatheters, it will undergo a sol-gel transition through physical and/or chemical cross-linking to form hydrogel to block blood flow. In addition, these in situ hydrogels can load drugs by pore embedding, electrostatic interaction, chemical bonding, etc., and have excellent sustained-release properties. This review summarizes the research progress of injectable in situ hydrogel vascular embolic agents in the past ten years, with a view to provide references for the development of new embolic agents in the future.
ABSTRACT
Abstract To investigate the effect of the dimethyl sulfoxide combined with cross-linking agents on microtensile bond strength, silver nitrate penetration and in situ degree of conversion analysis of adhesives to the erosive dentin treatment with Cola-based soft drink. One hundred and sixty-six molars were assigned to 20 groups: (1) Treatment: Sound dentin; Erosive dentin; Erosive dentin treated with primer of dimethyl sulfoxide; Erosive dentin treated with DMSO primer containing proanthocyanidin and rivoflavin; (2) Adhesive systems: iBond Universal and Scotchbond Universal; and (3) adhesive strategy: etch-and-rinse or self-etch strategy. After restoration, specimens were sectioned into sticks to be tested. The data from microtensile bond strength (MPa), silver nitrate penetration (%) and in situ degree of conversion (%) were analyzed by (three- and two-factor ANOVA; Tukey's test α=5%). The application of dimethyl sulfoxide combined of not with cross-linkers improved all properties evaluated when compared to only erosive dentin treatment with Cola-based soft drink. However, only when dimethyl sulfoxide was combined to cross-linkers, the values of the microtensile bond strength, silver nitrate penetration and in situ degree of conversion in erosive dentin treatment with Cola-based soft drink was similar to sound dentin, for both adhesives and adhesive strategies. The application of dimethyl sulfoxide combined with the collagen cross-linking agent contributed to increasing the bond strength and degree of conversion in erosive lesion dentin, at the same time that significantly reduction of nanoleakage in this substrate.
Resumo Este estudo investigou o efeito do dimetil sulfóxido combinado a agentes de reticulação de colágeno na resistência de união à microtração, infiltração de nitrato de prata e análise do grau de conversão por Micro-Raman de sistemas adesivos universais para a dentina erosionada por refrigerante a base de Cola. Cento e sessenta molares foram divididos em 20 grupos: (1) Tratamento: Dentina sadia; Dentina erosionada; Dentina erosionada tratada com primer de dimetil sulfóxido; Dentina erosionada tratada com primer contendo 6,5% de proantocianidina e; Dentina erosionada tratada com primer contendo 0,1% de rivoflavina; (2) Sistemas adesivos: iBond Universal e Scotchbond Universal; e (3) estratégia adesiva: estratégia condicionamento e lavagem ou autocondicionate. Após a restauração, os espécimes foram seccionados em palitos e testados. Os dados dos três testes foram analisados estatisticamente (ANOVA de 2 e 3 fatores e teste de Tukey; α = 5%). A aplicação de dimetil sulfóxido combinado ou não agentes de reticulação de colágeno melhorou todas as propriedades avaliadas quando comparado a dentina erosionada. Entretanto, apenas quando o dimetil sulfóxido foi combinado com agentes de reticulação de colágeno, os valores de adesão a dentina, infiltração de nitrato de prata e grau de conversão em dentina erosionada foi semelhante a dentina sadia, para os dois adesivos e estratégias adesivas. A aplicação de dimetil sulfóxido combinado com agentes de reticulação de colágeno contribuiu para aumentar a resistência de união e o grau de conversão dentro da camada híbrida na dentina erodida, ao mesmo tempo que reduziu significativamente a nanoinfiltração neste substrato.
ABSTRACT
ABSTRACT Purpose: Keratoconus presents certain specificities in pediatric patients compared with adults. The greatest challenge is because the disease is typically more severe and progresses faster in children. This retrospective study aimed to report crosslinking procedure in patients under 18 years of age and their follow-up for at least 24 months after the procedure. Methods: Overall, 12 eyes from 10 patients were studied and data, such as visual acuity with and without correction, maximum keratometry, corneal thickness, foveal thickness, and endothelial microscopy, were assessed at both preoperative and postoperative visits. Corneal crosslinking was performed in all patients. Results: A tendency toward reduced Kmax and improved Corrected Distance Visual Acuity at all postoperative moments. Only one of the 12 eyes exhibited increased Kmax of more than 1 D during a time frame longer than 12 months. Regarding pachymetry, a tendency for corneal thinning was observed in the first four months after surgery. Conclusion: Encouraging results were obtained regarding the stabilization of the disease, progression, and procedural safety, corroborating to other authors' findings. The significance of early diagnosis and short-term follow-up were highlighted.
RESUMO Objetivo: O ceratocone na população pediátrica apresenta algumas particularidades em relação à população adulta. O maior desafio é devido à doença ser geralmente mais severa e rapidamente progressiva em crianças. Métodos: Este artigo utiliza uma análise retrospectiva para relatar o uso do crosslinking em jovens menores de 18 anos e sua evolução pelo menos 24 meses após o procedimento. Foram estudados 12 olhos de 10 pacientes, e dados como acuidade visual com e sem correção, ceratometria máxima, espessura corneana, espessura foveal e microscopia endotelial avaliados no pré e pós-operatórios. O crosslinking corneano foi realizado em todos os pacientes pelo mesmo cirurgião. Resultados: Observou-se uma tendência de redução do valor do Kmax e melhora da acuidade visual corrigida em todos os momentos de pós operatório. Com relação à paquimetria, observou-se afinamento corneano do ponto mais fino, nos primeiros quatro meses de pós-operatório. Conclusão: Resultados encorajadores foram obtidos com relação à estabilização da doença, progressão e segurança do procedimento, corroborando com as conclusões de outros autores. A importância do diagnóstico precoce e do acompanhamento a curto prazo do paciente deve ser destacada.
Subject(s)
Adolescent , Adult , Child , Humans , Photochemotherapy , Keratoconus , Riboflavin/therapeutic use , Ultraviolet Rays , Retrospective Studies , Collagen/therapeutic use , Photosensitizing Agents/therapeutic use , Cornea , Corneal Topography , Cross-Linking Reagents/therapeutic use , Corneal Pachymetry , Keratoconus/surgery , Keratoconus/drug therapyABSTRACT
SUMMARY Introduction: Eggshell membrane (ESM) is a tissue found between the eggshell and the albumen of eggs that has attractive properties for use in drug delivery systems. Aim: To incorporate in ESM and used it as a model drug in release studies. The color change and FTIR analysis of the biopolymer proved the incorporation of nimesulide in ESM. Results: The drug uptake was 176.83 and 122.69 mg g-1 by natural and cross-linked ESM. Release studies were carried out using a spectrophotometric flow system in simulated intestinal fluid pH 7.4. The release profiles showed that after 60 minutes 54.55 and 42.58 % of the drug were released from natural and cross-linked ESM, respectively. Kinetics parameters indicated that drug release was better described by the Higuchi model and through a non-Fickian release. Conclusion: Considering these results is proved that ESM has the potential to become a polymeric matrix for drug release systems.
RESUMO Introdução: a membrana da casca do ovo (MCO) é um tecido encontrado entre a casca e o albúmen de ovos que possui propriedades atrativas para uso em sistemas de liberação de fármacos. Objetivo: incorporar à MCO e utilizá-la como fármaco modelo em estudos de liberação. Mudança de coloração e análises de FTIR do biopolímero comprovaram a incorporação da nimesulida na MCO. A incorporação do fármaco foi de 176,83 e 122,69 mg g-1 na MCO natural e reticulada, respectivamente. Resultados: os estudos de liberação foram realizados usando um sistema de fluxo espectrofotométrico em fluido intestinal simulado pH 7,4. Os perfis de liberação mostraram que após 60 minutos 54,55 e 42,58 % do medicamento foram liberados da MCO natural e reticulada, respectivamente. Os parâmetros cinéticos indicaram que a liberação do fármaco foi mais bem descrita pelo modelo de Higuchi e por meio de uma liberação não Fickiana. Conclusão: considerando estes resultados, fica comprovado que a MCO tem potencial para se tornar uma matriz polimérica para sistemas de liberação de fármacos.
RESUMEN Introducción: La membrana de cáscara de huevo (MCH) es un tejido que se encuentra entre la cáscara de huevo y la albúmina de los huevos que tiene propiedades atractivas para su uso en sistemas de administración de fármacos. Objetivo: Incorporar en MCH y utilizarla como fármaco modelo en estudios de liberación. El cambio de color y el análisis FTIR del biopolímero demostraron la incorporación de nimesulida en MCH. Resultados: La captación del fármaco fue de 176,83 y 122,69 mg g-1 por MCH natural y reticulado. Los estudios de liberación se llevaron a cabo utilizando un sistema de flujo espectrofotométrico en líquido intestinal simulado pH 7,4. Los perfiles de liberación mostraron que después de 60 minutos el 54,55 y el 42,58 % del fármaco se liberó de la MCH natural y reticulada, respectivamente. Los parámetros cinéticos indicaron que la liberación del fármaco se describió mejor mediante el modelo de Higuchi y mediante una liberación no Fickian. Conclusión: De acuerdo con estos resultados, el MCH tiene el potencial de convertirse en una matriz polimérica para sistemas de liberación de fármacos.