scholarly journals Comparison of Methods for Estimating Retinal Shape: Peripheral Refraction vs. Optical Coherence Tomography

2021 ◽  
Vol 10 (2) ◽  
pp. 174
Author(s):  
Katharina Breher ◽  
Alejandro Calabuig ◽  
Laura Kühlewein ◽  
Focke Ziemssen ◽  
Arne Ohlendorf ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Axial Length ◽  
Pearson Correlation ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Clinical Parameter ◽  
Mean Difference ◽  
Optical Coherence ◽  
Shape Estimation ◽  
Intraclass Correlation Coefficients

Retinal shape presents a clinical parameter of interest for myopia, and has commonly been inferred indirectly from peripheral refraction (PRX) profiles. Distortion-corrected optical coherence tomography (OCT) scans offer a new and direct possibility for retinal shape estimation. The current study compared retinal curvatures derived from OCT scans vs. PRX measurements in three refractive profiles (0° and 90° meridians, plus spherical equivalent) for 25 participants via Bland–Altman analysis. The radial differences between both procedures were correlated to axial length using Pearson correlation. In general, PRX- and OCT-based retinal radii showed low correlation (all intraclass correlation coefficients < 0.21). PRX found flatter retinal curvatures compared to OCT, with the highest absolute agreement found with the 90° meridian (mean difference +0.08 mm) and lowest in the 0° meridian (mean difference +0.89 mm). Moreover, a negative relation between axial length and the agreement of both methods was detected especially in the 90° meridian (R = −0.38, p = 0.06). PRX measurements tend to underestimate the retinal radius with increasing myopia when compared to OCT measurements. Therefore, future conclusions from PRX on retinal shape should be made cautiously. Rather, faster and more clinically feasible OCT imaging should be performed for this purpose.

Reliability of Corneal, Epithelial, and Stromal Thickness Mapping for a 9-mm Zone Using Spectral-Domain Optical Coherence Tomography

2021 ◽  
Author(s):  
Daniel Krause ◽  
Niklas Mohr ◽  
Mehdi Shajari ◽  
Wolfgang J. Mayer ◽  
Siegfried Priglinger ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Intraclass Correlation ◽  
Age Groups ◽  
Corneal Stroma ◽  
Correlation Coefficients ◽  
Spectral Domain ◽  
Optical Coherence ◽  
Noninvasive Technique ◽  
Intraclass Correlation Coefficients ◽  
Sd Oct

Abstract Purpose To evaluate the reliability of spectral-domain optical coherence tomography (SD-OCT; RTVue XR; Optovue, Inc., Fremont, CA, USA) for thickness mapping of the entire cornea (CT), corneal epithelium (ET). and corneal stroma (ST) over a 9-mm zone in healthy eyes. We sought to develop reference values for different age groups and elucidate potential sex- and age-dependent characteristics of corneal sublayer pachymetry maps. Methods Three consecutive SD-OCT scans were obtained in 166 healthy right eyes (mean age = 50 ± 20 years). The thickness maps contain 25 sectors over a 9-mm diameter zone. To test measurement reliability, intraclass correlation coefficients (ICC), coefficients of variation (CoV), and within-subject standard deviations (WSSD) were calculated. Results CT, ET, and ST ICCs ranged from 0.961 to 0.998, 0.896 to 0.945, and 0.955 to 0.998, respectively. CoV values for CT, ET, and ST ranged between 0.3 and 1.5%, 1.6 and 4.2%, and 0.4 and 1.7%, respectively. WSSD ranged from 6 to 41, 4 to 8, and 7 to 46 µm, respectively. A negative correlation was found between age and ET (p < 0.05) but not between age and ST or CT. No gender-related differences in CT, ET, or ST were detected. CoV of CT, ET, and ST measurements showed a positive correlation with age in 28, 64, and 28% of the sectors, respectively. Conclusion SD-OCT is a rapid and noninvasive technique that provides excellent reliability for corneal sublayer thickness measurements over a 9-mm zone. The reliability of the ET measurement seems to be negatively affected by age. Peripheral CT and global ET thin with age.

scholarly journals Pre-, Intra-, and Post-Operative Evaluation of Extraocular Muscle Insertions Using Optical Coherence Tomography: A Comparison of Four Devices

2019 ◽  
Vol 8 (10) ◽  
pp. 1732 ◽  
Author(s):  
Matthew S. Pihlblad ◽  
Andrew Troia ◽  
Sapna Tibrewal ◽  
Parth R. Shah
Keyword(s):  
Optical Coherence Tomography ◽  
Intraclass Correlation ◽  
Anterior Segment ◽  
Correlation Coefficients ◽  
Rectus Muscle ◽  
Strabismus Surgery ◽  
Optical Coherence ◽  
Intraclass Correlation Coefficients ◽  
Muscle Insertion ◽  
Operative Evaluation

OCT (optical coherence tomography) is widely used in ophthalmology and pediatric ophthalmology, but limited research has been done on the use of OCT in strabismus. This study investigates the use of different OCT machines to image rectus muscle insertions pre-, intra-, and post-operatively in pediatric strabismus patients. The OCT machines used in the study were a Bioptigen (Leica Microsystems Inc., Buffalo Grove, IL, USA), Spectralis HRA+OCT with Anterior Segment Module (Heidelberg Engineering, Heidelberg, Germany), Visante (Carl Zeiss, Oberkochen, Germany), and Zeiss Rescan 700 (Carl Zeiss, Oberkochen, Germany). Measurements from the machines were compared with the caliper distance measured during the strabismus surgery before disinsertion or after reattachment. The OCT machines had moderate (Bioptigen: 0.62) to good intraclass correlation coefficients (Rescan: 0.83, Spectralis: 0.85, Visante: 0.88) with intra-operative measurements. To our knowledge, this is the first study to use an operating microscope with integrated intra-operative OCT to image rectus muscle insertions. OCT is a useful tool in strabismus surgical patients in the pre-, intra-, and post-operative settings, particularly in patients who have had previous surgery, when the muscle insertion is unknown. The ability to accurately image rectus muscle insertions has significant implications for the management of strabismus patients.

scholarly journals A New Optical Coherence Tomography Method for Subfoveal Choroidal Thickness Measurement: A Single-center Observational Study

2020 ◽  
Author(s):  
Kyung Tae Kang ◽  
Ji Hye Jang ◽  
Yu Cheol Kim
Keyword(s):  
Optical Coherence Tomography ◽  
Observational Study ◽  
Choroidal Thickness ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
New Method ◽  
Optical Coherence ◽  
Single Center ◽  
Intraclass Correlation Coefficients ◽  
Single Center Observational Study

Abstract Background: Several macular pathologies are associated with choroidal vascular supply, and thus require choroidal thickness evaluation. However, there is no standard subfoveal choroidal thickness (SFCT) measuring method. This study investigated a new method to measure the SFCT, using optical coherence tomography.Methods: This is a single-center observational study. Eighty-two senior medical students participated as observers and independently measured the SFCT on five standard optical coherence tomography images of healthy adults in a tertiary care setting. They used three different methods: (1) the observer’s own method, (2) the conventional method, perpendicular to the retinal pigment epithelium, and (3) the new method, along a virtual line connecting the umbo with the most elevated point of the ellipsoid. Additionally, the SFCT angle—the angle between the measurement line and the vertical line of the image—was measured and compared between methods. The intraclass correlation coefficient was used to determine interpersonal variability. Results: The intraclass correlation coefficients for SFCT measured by methods 1, 2, and 3 were 0.853, 0.880, and 0.896, respectively (P < 0.001 for all). It was the highest with method 3; the intraclass correlation coefficients SFCT angles were 0.647, 0.842, and 0.307, respectively (P < 0.001 for all).Conclusions: The new method showed the lowest interpersonal variability, and could therefore be a reliable standard for SFCT measurement, even in foveae with a steep slope on optical coherence tomography.Trial registration: Not applicable

scholarly journals Measurement of Photoreceptor Layer in Glaucoma: A Spectral-Domain Optical Coherence Tomography Study

2011 ◽  
Vol 2011 ◽  
pp. 1-5 ◽  
Author(s):  
Ning Fan ◽  
Nina Huang ◽  
Dennis Shun Chiu Lam ◽  
Christopher Kai-shun Leung
Keyword(s):  
Optical Coherence Tomography ◽  
Confidence Interval ◽  
Outer Nuclear Layer ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Spectral Domain ◽  
Optical Coherence ◽  
Photoreceptor Layer ◽  
Intraclass Correlation Coefficients ◽  
Spectral Domain Oct

Objective.To measure and compare photoreceptor layer thickness between normal and glaucomatous eyes using spectral-domain optical coherence tomography (OCT).Methods. Thirty-eight healthy normal volunteers and 47 glaucoma patients were included in the analysis. One eye from each participant was randomly selected for macula imaging by a spectral-domain OCT (3D OCT-1000, Topcon, Tokyo, Japan). The foveal and parafoveal (1.5 mm from the fovea) outer nuclear layer (ONL) and inner and outer segments (IS+OS) layer thicknesses were measured by a single masked observer. The measurements were repeated 3 times in a random sample of 30 normal eyes to determine the repeatability coefficient and intraclass correlation coefficient.Results.The measurement variabilities of photoreceptor thickness were low. The respective intraclass correlation coefficients of ONL and IS+OS thicknesses were 0.96 (95% confidence interval: 0.94–0.98) and 0.82 (95% confidence interval 0.70–0.90). While there were no differences in parafoveal ONL and IS+OS thicknesses between normal and glaucoma groups (), the foveal ONL thickness was greater in glaucomatous eyes () than in normal eyes.Conclusions.Glaucomatous damage may involve structural change in the photoreceptor layer.

scholarly journals A Quantitative Comparison of Multispectral Refraction Topography and Autorefractometer in Young Adults

2021 ◽  
Vol 8 ◽  
Author(s):  
Yunru Liao ◽  
Zhenlan Yang ◽  
Zijing Li ◽  
Rui Zeng ◽  
Jing Wang ◽  
...  
Keyword(s):  
Correlation Coefficient ◽  
Pearson Correlation ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
High Agreement ◽  
Intraclass Correlation Coefficients ◽  
Repeatability And Reproducibility ◽  
The Mean

Purpose: Purpose of this study is to evaluate the measuring consistency of central refraction between multispectral refraction topography (MRT) and autorefractometry.Methods: This was a descriptive cross-sectional study including subjects in Sun Yat-sen Memorial Hospital from September 1, 2020, to December 31, 2020, ages 20 to 35 years with a best corrected visual acuity of 20/20 or better. All patients underwent cycloplegia, and the refractive status was estimated with autorefractometer, experienced optometrist and MRT. We analyzed the central refraction of the autorefractometer and MRT. The repeatability and reproducibility of values measured using both devices were evaluated using intraclass correlation coefficients (ICCs).Results: A total of 145 subjects ages 20 to 35 (290 eyes) were enrolled. The mean central refraction of the autorefractometer was −4.69 ± 2.64 diopters (D) (range −9.50 to +4.75 D), while the mean central refraction of MRT was −4.49 ± 2.61 diopters (D) (range −8.79 to +5.02 D). Pearson correlation analysis revealed a high correlation between the two devices. The intraclass correlation coefficient (ICC) also showed high agreement. The intrarater and interrater ICC values of central refraction were more than 0.90 in both devices and conditions. At the same time, the mean central refraction of experienced optometrist was −4.74 ± 2.66 diopters (D) (range −9.50 to +4.75D). The intra-class correlation coefficient of central refraction measured by MRT and subjective refraction was 0.939.Conclusions: Results revealed that autorefractometry, experienced optometrist and MRT show high agreement in measuring central refraction. MRT could provide a potential objective method to assess peripheral refraction.

scholarly journals Reproducibility and Validity of the 10-Meter Shuttle Ride Test in Wheelchair-Using Children and Adolescents With Cerebral Palsy

2013 ◽  
Vol 93 (7) ◽  
pp. 967-974 ◽  
Author(s):  
Olaf Verschuren ◽  
Maremka Zwinkels ◽  
Marjolijn Ketelaar ◽  
Femke Reijnders-van Son ◽  
Tim Takken
Keyword(s):  
Cerebral Palsy ◽  
Cardiorespiratory Fitness ◽  
Gold Standard ◽  
Pearson Correlation ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Peak Oxygen Uptake ◽  
Repeated Measurements ◽  
Manual Wheelchair ◽  
Intraclass Correlation Coefficients

BackgroundFor children with cerebral palsy (CP) who are able to walk or run, the 10-m shuttle run test is currently the test of choice to assess cardiorespiratory fitness. This test, however, has not yet been examined in wheelchair-using youth with CP.ObjectiveThe purpose of this study was to investigate the test-retest reproducibility and validity of the 10-m shuttle ride test (SRiT) in youth with CP.DesignRepeated measurements of the SRiT were obtained.MethodsTwenty-three individuals with spastic CP (18 boys, 5 girls; mean age=13.3 years, SD=3.6 years) using a manual wheelchair for at least part of the day participated in this study. During the study, all participants performed one graded arm exercise test (GAET) and 2 identical SRiTs within 2 weeks. Peak oxygen uptake (V̇o2peak), peak heart rate (HRpeak), and respiratory exchange ratio (RER) were recorded. Intraclass correlation coefficients (2,1), the smallest detectable difference, and the limits of agreement (LOA) were calculated. The association between the results of the SRiT and GAET was tested using Pearson correlation coefficients.ResultsIntraclass correlation coefficients (.99, 95% confidence interval=.98–1.00) for all variables indicated highly acceptable reproducibility. The LOA analysis revealed satisfactory levels of agreement. The SRiT variables demonstrated strong, significant positive correlations for V̇o2peak values obtained during the SRiT and the GAET (r=.84, P&lt;.01).LimitationsAlthough the GAET is considered the gold standard, the cardiorespiratory demand during the GAET was significantly lower compared with during the SRiT. Future studies should determine whether the GAET can still be accepted as the gold standard for upper-extremity exercise.ConclusionsThe SRiT is a reproducible and valid test for measuring cardiorespiratory fitness in youth with spastic CP who self-propel a manual wheelchair.

scholarly journals Comparison of Fourier-Domain and Time-Domain Optical Coherence Tomography in the Measurement of Thinnest Corneal Thickness in Keratoconus

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Chunxiao Wang ◽  
Xueying Xia ◽  
Bishan Tian ◽  
Shiyou Zhou
Keyword(s):  
Optical Coherence Tomography ◽  
Time Domain ◽  
Pearson Correlation ◽  
Corneal Thickness ◽  
Intraclass Correlation ◽  
Fourier Domain ◽  
Optical Coherence ◽  
Highly Correlated ◽  
Time Domain Oct

Objective. To compare fourier-domain optical coherence tomography (FD-OCT) and time-domain OCT (TD-OCT) in the determination of thinnest corneal thickness (TCT).Methods. This study included 55 keratoconus patients and 50 healthy volunteers. The RTVue-OCT (FD-OCT) and Visante-OCT (TD-OCT) were used for the measurement of the TCT. Three consecutive scans were performed. The comparison and agreement between the two modalities were analyzed by pairedt-test, the Pearson correlation, intraclass correlation coefficient (ICC), and Bland-Altman plots. intraobserver repeatability was analyzed by the intraobserver within-subject standard deviation (S(w)), coefficient of variation (CV(w)), and ICC.Results. The TCT value of normal corneas was higher by RTVue-OCT (530.4 ± 19.7 μm) than Visante-OCT (521.5 ± 18.3 μm) (p<0.001). For keratoconus eyes, the TCT was 425.0 ± 58.2 μm and 424.4 ± 55.7 μm (difference being 0.6 ± 10.2 μm,p=0.604). Strong correlation (r= 0.938∼0.985) (ICC = 0.915–0.984) was observed between the two OCTs, and each OCT exhibited excellent repeatability in determining the TCT in all subjects (ICC = 0.984–0.994).Conclusions. The values of TCT obtained from RTVue-OCT and Visante-OCT were highly correlated; however, the two values were different. Both OCT instruments exhibited good intraobserver reliability. The existence of systematic differences suggested that the two instruments cannot be used interchangeably.

Assessing the Motor Status Score: A Scale for the Evaluation of Upper Limb Motor Outcomes in Patients after Stroke

2002 ◽  
Vol 16 (3) ◽  
pp. 283-289 ◽  
Author(s):  
Mark Ferraro ◽  
Jennifer Hogan Demaio ◽  
Jennifer Krol ◽  
Chris Trudell ◽  
Keren Rannekleiv ◽  
...  
Keyword(s):  
Correlation Coefficient ◽  
Upper Limb ◽  
Pearson Correlation ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Pearson Correlation Coefficient ◽  
Maximum Score ◽  
Intraclass Correlation Coefficients ◽  
Upper Extremity Impairment ◽  
Motor Outcomes

The Motor Status Scale (MSS) measures shoulder, elbow (maximum score = 40), wrist, hand, and finger movements (maximum score = 42), and expands the measurement of upper extremity impairment and disability provided by the Fugl-Meyer (FM) score. This work examines the interrater reliability and criterion validity of the MSS performed in patients admitted to a rehabilitation hospital 21 ± 4 days after stroke. Using the MSS and the FM, 7 occupational therapists masked to each other’s judgments, evaluated 12 consecutive patients with stroke. Two therapists evaluated 6 additional patients on consecutive days. Intraclass correlation coefficients were significant for each group of raters for the shoulder/elbow and for the wrist/hand (P < 0.0001); test-retest measures were also significant for the shoulder/elbow (Pearson correlation coefficient r = 0.99, P < 0.004) and for the wrist/hand (Pearson correlation coefficient r = 0.99, P < 0.003). The internal item consistency for the overall MSS was significant (Cronbach alpha = 0.98, P < 0.0001). Finally the correlation between the MSS and the FM (R 2 = 0.964) was significant (P < 0.0001). The MSS affords a reliable and valid assessment of upper limb impairment and disability following stroke.

scholarly journals Comparison of the Repeatability of Macular Vascular Density Measurements Using Four Optical Coherence Tomography Angiography Systems

2019 ◽  
Vol 2019 ◽  
pp. 1-7 ◽  
Author(s):  
Jingyuan Yang ◽  
Mingzhen Yuan ◽  
Erqian Wang ◽  
Youxin Chen
Keyword(s):  
Optical Coherence Tomography ◽  
Optical Coherence Tomography Angiography ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Vessel Density ◽  
Vascular Density ◽  
Optical Coherence ◽  
Cross Sectional ◽  
Capillary Plexus ◽  
Scan Pattern

The aim of this study was to compare the repeatability of optical coherence tomography angiography (OCT-A) measurements of macular vessel density using four OCT-A systems, including Heidelberg Spectralis HRA, Optovue RTVue XR, Zeiss Cirrus HD-OCT 5000, and Topcon DRI OCT Triton. A cross-sectional design was used for this study. The vascular density and vascular length density of the superficial and deep retinal capillary plexuses were imaged with OCT-A using 3 mm and 6 mm scan patterns and were calculated using ImageJ. Comparisons of intraclass correlation coefficients (ICC) were conducted. We found that the OCT-A systems had various levels of repeatability. Zeiss had better repeatability for vessel density than the other systems (overall ICC = 0.936). Optovue had better repeatability for vessel length density when the 6 mm scan pattern was used (ICC = 0.680 and 0.700 for retinal superficial and deep capillary plexus, respectively). We concluded that repeatability varied when different scan patterns of various OCT-A systems were used for imaging the superficial retinal and deep capillary plexuses. Results should be seen as valid only for a given method. The repeatability of various OCT-A systems should be considered in clinical practice and in clinical trials that use OCT-A metrics as outcome measures.

scholarly journals Reliability of a Three-Dimensional Wound Camera and Correlation With Routine Ruler Measurement in Diabetes-Related Foot Ulceration

2020 ◽  
pp. 193229682097465
Author(s):  
Joel Willem Johan Lasschuit ◽  
Jill Featherston ◽  
Katherine Thuy Trang Tonks
Keyword(s):  
Interobserver Reliability ◽  
Pearson Correlation ◽  
Intraclass Correlation ◽  
Three Dimensional ◽  
Correlation Coefficients ◽  
Area Measurement ◽  
Foot Care ◽  
Foot Ulceration ◽  
Intraclass Correlation Coefficients ◽  
Service Setting

Background: In an era of increasing technology and telehealth utilization, three-dimensional (3D) wound cameras promise reliable, rapid, and touch-free ulceration measurements. However, reliability data for commercially available devices in the diabetes foot service setting is lacking. We aimed to evaluate the reliability of diabetes-related foot ulceration measurement using a 3D wound camera in comparison to the routinely used ruler and probe. Method: Participants were prospectively recruited from a tertiary interdisciplinary diabetes foot service. Ulcerations were measured at each visit by two blinded observers, first by ruler and probe, and then using a 3D wound camera twice. Reliability was evaluated using intraclass correlation coefficients (ICC). Measurement methods were compared by Pearson correlation. Results: Sixty-three ulcerations affecting 38 participants were measured over 122 visits. Interobserver reliability of ruler measurement was excellent for estimated area (ICC 0.98, 95% CI 0.97-0.98) and depth (ICC 0.93, 95% CI 0.90-0.95). Intraobserver and interobserver reliability of the 3D wound camera area was excellent (ICC 0.96, 95%CI 0.95-0.97 and 0.97 95% CI 0.96-0.98, respectively). Depth was unrecordable in over half of 3D wound camera measurements, and reliability was inferior to probe measurement. Area correlation between methods was good ( R = 0.88 and 0.94 per observer); however, depth correlation was poor ( R = 0.49 and 0.65). Conclusions: 3D wound cameras offer practical advantages over ruler-based measurement. In diabetes-related foot ulceration, the reliability and comparability of area measurement was excellent across both methods, although depth was more reliably obtained by the probe. These limitations, together with cost, are important considerations if implementing this technology in diabetes foot care.

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