Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
5,706
result(s) for
"Cornea - pathology"
Sort by:
The correlation between myopia severity and stress–strain index (SSI) using the Corneal Visualization Scheimpflug Technology (Corvis ST)
2025
This study aimed to investigate the correlation between myopia severity and the stress–strain index (SSI), measured with the Corneal Visualization Scheimpflug Technology (Corvis ST) device. The subjects were divided into two groups, based on both the axial length (AL) and spherical equivalent refraction (SER): 22–26.00 AL group (22 mm < AL < 26.00 mm) associated with SER of less than − 6.00D, and ≥ 26.00 AL group (AL ≥ 26.00 mm) associated with SER over − 6.00D. The differences in the Corvis ST-derived dynamic corneal response parameters and stiffness parameters between the two groups were investigated. The correlation between SSI and AL, SER, age, ratio of AL to radius of corneal curvature (CR) (AL/CR), and axial length minus anterior chamber depth (ACD) (AL-ACD) were analyzed. The SSI (0.95 ± 0.13 in the 22–26.00 AL group and 0.86 ± 0.15 in the ≥ 26.00 AL group) were significantly different between the two groups (
P
< 0.01). In the ≥ 26.00 AL group, there was evidence of a weak negative correlation between SSI and AL (r = − 0.265,
P
< 0.01), AL/CR (r = − 0.376,
P
< 0.01), and AL-ACD (r = − 0.224,
P
< 0.01); and a weak positive correlation between SSI and SER (r = 0.251,
P
< 0.01). However, in the 22–26.00 AL group, there was no correlation between SSI and AL, AL-ACD, AL/CR or SER (
P
> 0.05). SSI was significantly correlated with AL, which is the major determinant of SER, in the ≥ 26.00 AL group. This correlation was not affected with CR and ACD, as both AL/CR and AL-ACD also correlated with SSI at the same degree.
Journal Article
Comparison of changes in corneal volume and corneal thickness after myopia correction between LASIK and SMILE
by
Kreutzer, Thomas
,
Kohnen, Thomas
,
Shajari, Mehdi
in
Adult
,
Biology and Life Sciences
,
Care and treatment
2021
Myopia is the most common refractive error. Surgical correction with laser is possible. LASIK and SMILE are the techniques currently most used. Aim of the study was to compare changes in corneal volume and thickness after the respective laser treatment. 104 eyes of 52 patients were matched based on refractive error into two equally sized groups, either treated with LASIK or SMILE. Measurements were obtained from the Scheimpflug camera (Pentacam) preoperatively and at 3 and 12 months postoperatively. 3 months postoperatively, the flapless SMILE procedure resulted in a significant overall greater loss of corneal volume (P < 0.01) and corneal thickness (P < 0.01) compared to LASIK. No significant difference was found when comparing the 3 to 12-months values in each group. Within the currently used ranges of refractive error correction, loss in central corneal thickness and corneal volume with SMILE is higher in comparison to LASIK. As greater loss in corneal volume and thickness might contribute to higher level of corneal instability maximum ranges of refractive error correction with SMILE should not supersede those set currently for LASIK until more long-term results on corneal ectasia are available for SMILE.
Journal Article
Collagens and proteoglycans of the cornea: importance in transparency and visual disorders
by
Malecaze, Francois
,
Massoudi, Dawiyat
,
Galiacy, Stephane D.
in
Animals
,
Biomedical and Life Sciences
,
Biomedicine
2016
The cornea represents the external part of the eye and consists of an epithelium, a stroma and an endothelium. Due to its curvature and transparency this structure makes up approximately 70 % of the total refractive power of the eye. This function is partly made possible by the particular organization of the collagen extracellular matrix contained in the corneal stroma that allows a constant refractive power. The maintenance of such an organization involves other molecules such as type V collagen, FACITs (fibril-associated collagens with interrupted triple helices) and SLRPs (small leucine-rich proteoglycans). These components play crucial roles in the preservation of the correct organization and function of the cornea since their absence or modification leads to abnormalities such as corneal opacities. Thus, the aim of this review is to describe the different corneal collagens and proteoglycans by highlighting their importance in corneal transparency as well as their implication in corneal visual disorders.
Journal Article
Management of belantamab mafodotin-associated corneal events in patients with relapsed or refractory multiple myeloma (RRMM)
by
Callander, Natalie S
,
Sborov, Douglas
,
Nooka, Ajay K
in
Cornea
,
Eye examinations
,
Monoclonal antibodies
2021
Belantamab mafodotin (belamaf) demonstrated deep and durable responses in patients with heavily pretreated relapsed or refractory multiple myeloma (RRMM) in DREAMM-2 (NCT03525678). Corneal events, specifically keratopathy (including superficial punctate keratopathy and/or microcyst-like epithelial changes (MECs), eye examination findings with/without symptoms), were common, consistent with reports from other antibody–drug conjugates. Given the novel nature of corneal events in RRMM management, guidelines are required for their prompt identification and appropriate management. Eye examination findings from DREAMM-2 and insights from hematology/oncology investigators and ophthalmologists, including corneal specialists, were collated and used to develop corneal event management guidelines. The following recommendations were formulated: close collaboration among hematologist/oncologists and eye care professionals is needed, in part, to provide optimal care in relation to the belamaf benefit–risk profile. Patients receiving belamaf should undergo eye examinations before and during every treatment cycle and promptly upon worsening of symptoms. Severity of corneal events should be determined based on corneal examination findings and changes in best-corrected visual acuity. Treatment decisions, including dose modifications, should be based on the most severe finding present. These guidelines are recommended for the assessment and management of belamaf-associated ocular events to help mitigate ocular risk and enable patients to continue to experience a clinical benefit with belamaf.
Journal Article
Detection of Diabetic Sensorimotor Polyneuropathy by Corneal Confocal Microscopy in Type 1 Diabetes: A concurrent validity study
by
Bril, Vera
,
Orszag, Andrej
,
Paulson, Jenna
in
Accuracy
,
Adult
,
Biological and medical sciences
2012
OBJECTIVE: We aimed to determine the corneal confocal microscopy (CCM) parameter that best identifies diabetic sensorimotor polyneuropathy (DSP) in type 1 diabetes and to describe its performance characteristics. RESEARCH DESIGN AND METHODS: Concurrent with clinical and electrophysiological examination for classification of DSP, CCM was performed on 89 type 1 diabetic and 64 healthy subjects to determine corneal nerve fiber length (CNFL), density, tortuosity, and branch density. Area under the curve (AUC) and optimal thresholds for DSP identification in those with diabetes were determined by receiver operating characteristic (ROC) curve analysis. RESULTS: DSP was present in 33 (37%) subjects. With the exception of tortuosity, CCM parameters were significantly lower in DSP case subjects. In ROC curve analysis, AUC was greatest for CNFL (0.88) compared with fiber density (0.84, P = 0.0001), branch density (0.73, P < 0.0001), and tortuosity (0.55, P < 0.0001). The threshold value that optimized sensitivity and specificity for ruling in DSP was a CNFL of ≤14.0 mm/mm2 (sensitivity 85%, specificity 84%), associated with positive and negative likelihood ratios of 5.3 and 0.18. An alternate approach that used separate threshold values maximized sensitivity (threshold value ≥15.8 mm/mm2, sensitivity 91%, negative likelihood ratio 0.16) and specificity (≤11.5 mm/mm2, specificity 93%, positive likelihood ratio 8.5). CONCLUSIONS: Among CCM parameters, CNFL best discriminated DSP cases from control subjects. A single threshold offers clinically acceptable operating characteristics, although a strategy that uses separate thresholds to respectively rule in and rule out DSP has excellent performance while minimizing unclassified subjects. We hypothesize that values between these thresholds indicate incipient nerve injury that represents those individuals at future neuropathy risk.
Journal Article
Refractive improvements and safety with topography-guided corneal crosslinking for keratoconus: 1-year results
2017
PurposeTo assess the refractive improvements and the corneal endothelial safety of an individualised topography-guided regimen for corneal crosslinking in progressive keratoconus.MethodsAn open-label prospective randomised clinical trial was performed at the Department of Clinical Sciences, Ophthalmology, Umeå University Hospital, Umeå, Sweden. Thirty-seven patients (50 eyes) with progressive keratoconus planned for corneal crosslinking were included. The patients were randomised to topography-guided crosslinking (photorefractive intrastromal crosslinking (PiXL); n=25) or uniform 9 mm crosslinking (corneal collagen crosslinking (CXL); n=25). Visual acuity, refraction, keratometry (K1, K2 and Kmax) and corneal endothelial morphometry were assessed preoperatively and at 1, 3, 6 and 12 months postoperatively. The PiXL treatment involved an asymmetrical treatment zone centred on the area of maximum corneal steepness with treatment energies ranging from 7.2 to 15.0 J/cm2; the CXL treatment was a uniform 9 mm 5.4 J/cm2 pulsed crosslinking. The main outcome measures were changes in refractive errors and corneal endothelial cell density.ResultsThe spherical refractive errors decreased (p<0.05) and the visual acuity improved (p<0.01) at 3, 6 and 12 months after PiXL, but not after CXL. The between-groups differences, however, were not significant. K2 and Kmax decreased at 3, 6 and 12 months after PiXL (p<0.01), but not after CXL (p<0.01 when comparing the two treatments). No corneal endothelial cell loss was seen after either treatment.ConclusionsIndividualised topography-based crosslinking treatment centred on the ectatic cone has the potential to improve the corneal shape in keratoconus with decreased spherical refractive errors and improved visual acuity, without damage to the corneal endothelium.Trial registration numberNCT02514200, Results.
Journal Article
A randomised, double-masked comparison study of diquafosol versus sodium hyaluronate ophthalmic solutions in dry eye patients
by
Watanabe, Hitoshi
,
Ohashi, Yuichi
,
Takamura, Etsuko
in
Aqueous solutions
,
Biological and medical sciences
,
Clinical Trial
2012
Aims To compare the efficacy and safety of 3% diquafosol ophthalmic solution with those of 0.1% sodium hyaluronate ophthalmic solution in dry eye patients, using mean changes in fluorescein and rose bengal staining scores as endpoints. Trial design and methods In this multicenter, randomised, double-masked, parallel study of 286 dry eye patients with fluorescein and rose bengal staining scores of ≥3 were randomised to the treatment groups in a 1 : 1 ratio. Efficacy and safety were evaluated after drop-wise instillation of the study drug, six times daily for 4 weeks. Results After 4 weeks, the intergroup difference in the mean change from baseline in fluorescein staining score was −0.03; this verified the non-inferiority of diquafosol. The mean change from baseline in rose bengal staining score was significantly lower in the diquafosol group (p=0.010), thus verifying its superiority. The incidence of adverse events was 26.4% and 18.9% in the diquafosol and sodium hyaluronate groups, respectively, with no significant difference. Conclusions Diquafosol (3%) and sodium hyaluronate (0.1%) exhibit similar efficacy in improving fluorescein staining scores of dry eye patients, whereas, diquafosol exhibits superior efficacy in improving rose bengal staining scores. Diquafosol has high clinical efficacy and is well tolerated with a good safety profile.
Journal Article
Comparison of intraepidermal nerve fiber density and confocal corneal microscopy for neuropathy
2024
Objective Compare the diagnostic characteristics of intraepidermal nerve fiber density (IENFD) and confocal corneal microscopy (CCM) for distal symmetric polyneuropathy (DSP) and small fiber neuropathy (SFN). Methods Participants with obesity were recruited from bariatric surgery clinics and testing was performed prior to surgery. DSP and SFN were determined using the Toronto consensus definitions of probable neuropathy. IENFD was assessed from 3 mm punch biopsies of the distal leg and proximal thigh. CCM was performed on both eyes with manual and automated counting. The Michigan Neuropathy Screening Instrument questionnaire (MNSIq) was also completed. Diagnostic capability was determined using areas under the receiver operating characteristics curve (AUC) from logistic regression. Results We enrolled 140 participants (mean [standard deviation [SD]] age: 50.3 years [7.1], 77.1% female, BMI: 44.4 kg/m2 [6.7]). In this population, 22.9% had DSP and 14.3% had SFN. Distal leg IENFD had the largest AUC (95% confidence interval) for DSP (0.78, 0.68–0.89) and SFN (0.85, 0.75–0.96). Proximal thigh IENFD (DSP: AUC: 0.59, 0.48–0.69, SFN: AUC: 0.59, 0.46–0.73) and CCM metrics (DSP: AUC range: 0.55–0.60, SFN: AUC range: 0.45–0.62) had poorer diagnostic capability than distal leg IENFD for DSP/SFN (P < 0.05). MNSIq had similar diagnostic capability to distal leg IENFD for both DSP/SFN (DSP: AUC: 0.76, 0.68–0.85, SFN: AUC: 0.81, 0.73–0.88). More participants (52%) preferred skin biopsies to CCM. Interpretation Distal leg IENFD was the best quantitative measure of DSP/SFN. CCM had poor diagnostic characteristics and fewer patients preferred this test to IENFD. The MNSIq had similar diagnostic characteristics to distal leg IENFD, indicating its value as a diagnostic tool in the clinical setting. Clinical Trial Registration clinicaltrials.gov: NCT03617185.
Journal Article
Effect of upper eyelid blepharoplasty with or without orbicularis oculi muscle removal on anterior segment parameters, keratometry, and ocular biometry
2024
Purpose
To evaluate the effect of upper eyelid blepharoplasty with or without the removal of a strip of orbicularis oculi muscle on corneal topographic parameters, anterior segment parameters, intraocular pressure, and ocular biometry.
Method
This prospective study examined 428 eyes of 214 patients with dermatochalasis. Patients were divided into two groups randomly: those who underwent orbicularis oculi muscle excision (Group 1) during blepharoplasty and those who did not (Group 2). Following a detailed ophthalmological examination, corneal topography was used to evaluate the eyes anterior chamber depth (ACD), iridocorneal angle (ICA), keratometry measurements, and corneal astigmatism (CA) in the preoperative and postoperative first and third months. Ocular biometry was used to assess axial length (AXL) and intraocular lens (IOL) power. Goldmann applanation tonometry was used to measure intraocular pressure (IOP).
Results
The age and gender distribution between the groups were similar (
p
= 0.595 and
p
= 0.493, respectively). In Group 1, the mean steep keratometry (K2) value increased by 1.1 D and the mean CA increased by 0.81 D in the first month (
p
< 0.001 for both comparisons). The increases in K2 and CA were 0.7 D and 0.63 D, respectively, in Group 2 (
p
< 0.001 and
p
= 0.004, respectively). At the postoperative third month, both groups demonstrated statistically significant persistent elevations in K2 and CA values (
p
< 0.05 for all comparisons) compared to preoperative measurements. Group 1 exhibited statistically significant decreases in both IOL power calculations (0.43 D according to the Barrett formula and 0.40 D according to the SRK/T formula,
p
< 0.001, for both) and ICA (38.1 ± 4.7° vs. 35.8 ± 4.1°,
p
= 0.009) measurements at the only one-month postoperative follow-up. IOP, AXL, and ACD measurements did not exhibit any significant changes in both groups at the first and third postoperative months.
Conclusion
In addition to changes in keratometry and CA, blepharoplasty with muscle excision significantly decreased IOL power and ICA. It may be beneficial to inquire about recent blepharoplasty history and the surgical technique employed in patients scheduled for cataract or refractive surgery.
Journal Article
Differential precision of corneal Pentacam HR measurements in early and advanced keratoconus
2016
Background/aimsSerial Scheimpflug corneal tomography to monitor the progression of keratoconus has become standard practice in most countries where corneal cross-linking is available. The tomographic definitions of progression are, however, poorly defined. The aims of this study were: (a) to estimate the 95% limits of intraobserver and interobserver agreement of corneal shape parameters on Pentacam in patients with keratoconus and (b) to investigate whether these limits of agreement varied according to disease severity.Methods96 adult patients with keratoconus and no corneal scarring or history of previous surgery were recruited from a corneal clinic in a tertiary ophthalmology hospital. One eye of each subject was scanned twice by each of the two observers with the Pentacam HR. 95% limits of intraobserver and interobserver agreement for K1, K2, Kmax and corneal thickness at the thinnest corneal location (TCT) were calculated.ResultsReproducibility of keratometry measures was better for early keratoconus than advanced keratoconus. In patients of Pentacam-derived Krumeich stage 1 or 2, the 95% limits of interobserver agreement for Kmax were from −0.90 to 1.01. In patients of Pentacam-derived Krumeich stage >2, the 95% limits of interobserver agreement for Kmax were from −3.71 to 3.86.ConclusionsKeratometric measurements on Pentacam HR are less reproducible in advanced keratoconus than in early keratoconus. In patients of Pentacam-derived Krumeich stage 1 or 2, an increase in K1, K2 or Kmax of more than 1 dioptre is likely to represent the real change in the corneal shape.
Journal Article