Tag: nevin manimala

J Refract Surg. 2022 Jul;38(7):465-473. doi: 10.3928/1081597X-20220516-01. Epub 2022 Jul 1.

ABSTRACT

PURPOSE: To explore ocular refraction shift after Neodymium: yttrium aluminum garnet (Nd:YAG) posterior capsulotomy in pseudophakic eyes.

METHODS: A systematic literature search was performed in the PubMed, Embase, and Cochrane Library databases until November 10, 2021. Studies on the evaluation of changes in spherical equivalent (SE), cylindrical error (CE), or anterior chamber depth (ACD) after Nd:YAG laser capsulotomy were included in the meta-analysis. The review was registered in the international platform of registered systematic review and meta-analysis protocols (INPLASY202120059).

RESULTS: A total of 805 eyes from 18 studies were included in the final analysis. The pooled mean differences in SE from baseline to postoperative follow-up points were not significant (1 hour: 0.04 diopters [D], 95% CI: -0.13 to 0.21, P = .644; 1 week: 0.04 D, 95% CI: -0.12 to 0.20, P = .640; 1 month: 0.05 D, 95% CI: -0.06 to 0.16, P = .349). There was no significant difference between baseline CE and any subsequent visit (1 week: 0.14 D, 95% CI: -0.06 to 0.33, P = .172; 1 month: 0.17 D, 95% CI: -0.04 to 0.38, P = .108). No statistical difference in ACD from baseline was observed either (1 hour: 0.01 mm, 95% CI: -0.07 to 0.09, P = .846; 1 week: -0.12 mm, 95% CI: -0.24 to 0.01, P = .079; 1 month: -0.06, 95% CI: -0.14 to 0.01, P = .110).

CONCLUSIONS: Neither ocular refraction nor ACD changed within 1 month after laser capsulotomy, suggesting laser capsulotomy did not affect ocular refraction in short-term observation. [J Refract Surg. 2022;38(7):465-473.].

PMID:35858199 | DOI:10.3928/1081597X-20220516-01

J Refract Surg. 2022 Jul;38(7):422-427. doi: 10.3928/1081597X-20220602-02. Epub 2022 Jul 1.

ABSTRACT

PURPOSE: To determine the reliability of the percentage of tissue altered (PTA) calculation as part of the planning strategy for myopic laser in situ keratomileusis (LASIK) by comparing the estimated PTA provided by preoperative calculation to the postoperative PTA actually achieved in microkeratome-assisted myopic LASIK.

METHODS: This retrospective study included 3,624 eyes of 3,624 patients who underwent mechanical microkeratome-assisted LASIK surgery for myopic correction. The calculated preoperative PTA values based on the planned flap thickness and ablation depth were compared with the actual achieved postoperative PTA using the difference of corneal central thickness postoperatively for assessing the achieved ablation depth and the intraoperative ultrasound-assisted flap thickness measurement. Regression analysis was performed to reveal preoperative parameters that might influence PTA calculation accuracy.

RESULTS: The mean difference between the estimated and achieved PTA was 0.451 ± 3.45% (P < .001) (95% CI: 0.3708 to 0.5322) with a preoperative and postoperative mean PTA of 31.07 ± 4.07% and 31.52 ± 5.78%, respectively. The differences between the achieved and planned maximum ablation depth and flap thickness were 4.32 ± 13.70 µm (P < .001) and -1.61 ± 13.66 µm (P < .001), respectively.

CONCLUSIONS: Although a statistically significant difference was found between the preoperative calculated PTA and actually achieved PTA, the difference in PTA value (less than 1%) was clinically non-significant and indicated a highly reliable metric for preoperative refractive surgery planning. [J Refract Surg. 2022;38(7):422-427.].

PMID:35858196 | DOI:10.3928/1081597X-20220602-02

J Refract Surg. 2022 Jul;38(7):443-449. doi: 10.3928/1081597X-20220602-01. Epub 2022 Jul 1.

ABSTRACT

PURPOSE: To assess the accuracy of the following intraocular lens (IOL) power formulas: Barrett True-K No History (BTKNH), Emmetropia Verifying Optical 2.0 Post Myopic LASIK/PRK (EVO 2.0), Haigis-L, American Society of Cataract and Refractive Surgery (ASCRS) average, and Shammas, designed for patients who have undergone previous myopic refractive surgery, independent of preexisting clinical history and corneal tomographic measurements.

METHODS: Data from 302 eyes of 302 patients who previously underwent myopic refractive surgery and had cataract surgery done by a single surgeon with only one IOL type inserted were included. The predicted refraction was calculated for each of the formulas and compared with the actual refractive outcome to give the prediction error. Subgroup analysis based on the axial length and mean keratometry was performed.

RESULTS: On the basis of mean absolute prediction error (MAE), the formulas were ranked as follows: Haigis-L (0.61 diopters [D]), ASCRS average (0.63 D), BTKNH (0.67 D), EVO 2.0 (0.68 D), and Shammas (0.69 D). The Haigis-L had a statistically significant lower MAE compared with all formulas (P < .05) except the ASCRS average. Hyperopic mean prediction errors were seen in all formulas for axial lengths of greater than 30 mm or mean keratometry values of 35.00 diopters or less.

CONCLUSIONS: The Haigis-L and the ASCRS average formulas provided the most accurate results in the overall population evaluated in this study. Moreover, according to data observed, it is important to be careful handling very long eyes and very flat corneas because hyperopic refractions could be more common. [J Refract Surg. 2022;38(7):443-449.].

PMID:35858195 | DOI:10.3928/1081597X-20220602-01

J Refract Surg. 2022 Jul;38(7):404-413. doi: 10.3928/1081597X-20220516-03. Epub 2022 Jul 1.

ABSTRACT

PURPOSE: To report subjective and objective quality of vision (QoV) results for high myopic small incision lenticule extraction (SMILE) between -9.00 and -13.00 diopters (D).

METHODS: This was a prospective study recruiting 114 patients undergoing SMILE with attempted spherical equivalent refraction (SEQ) correction from -9.00 to -13.00 D, and cylinder up to 5.00 D. Patients were informed before surgery of the increased risk of QoV symptoms. Patients completed the Rasch validated QoV questionnaire. Objective QoV was assessed by corneal and whole eye aberrations, HD Analyzer Objective Scatter Index (OSI) (Keeler), and contrast sensitivity. Patient satisfaction was assessed on a scale from 0 (very dissatisfied) to 10 (very satisfied). Individual item and total Rasch-scaled scores for the three subscales (frequency, severity, and bothersomeness) of the QoV questionnaire were calculated before and 12 months after surgery.

RESULTS: The mean patient satisfaction score was 9.27 ± 1.18 (range: 2 to 10), 8 or higher in 93%, and 7 or higher in 98% of patients. One patient with a satisfaction score of 2 had a simple refractive error re-treatment and then reported a satisfaction score of 10. The total mean ± standard deviation Rasch-scaled QoV score for the frequency, severity, and bothersomeness subscales before surgery was 24 ± 19, 20 ± 16, and 19 ± 18, respectively. Scores increased after surgery to 41 ± 18, 32 ± 16, and 30 ± 21, respectively (P < .001). Corneal aberrations (6 mm, OSI) increased on average by 0.39 µm for spherical aberration, 0.41 µm for coma, and 0.56 µm for higher order aberrations root mean square. OSI increased on average by 0.58. There was a small but statistically significant improvement in contrast sensitivity at 3, 6, 12, and 18 cycles per degree. There were no statistically significant correlations found between subjective scores for starbursts and objective measurements.

CONCLUSIONS: Satisfaction was high following SMILE for high myopia. As expected, there was an increase in QoV symptoms, mainly glare and starbursts. The acceptance of QoV symptoms for high myopic SMILE was high, indicating that residual refractive error and visual acuity are the major drivers for patient satisfaction with appropriate preoperative informed consent. [J Refract Surg. 2022;38(7):404-413.].

PMID:35858192 | DOI:10.3928/1081597X-20220516-03

J Refract Surg. 2022 Jul;38(7):428-434. doi: 10.3928/1081597X-20220516-02. Epub 2022 Jul 1.

ABSTRACT

PURPOSE: To evaluate and compare the performance of a trifocal diffractive intraocular lens (IOL) and a lens combining a bifocal diffractive profile and extended depth of focus (EDOF) profile.

METHODS: This non-randomized, prospective comparative study included 42 patients (84 eyes) undergoing lens surgery with implantation of either the FineVision HP trifocal IOL (PhysIOL) or TECNIS Synergy bifocal EDOF IOL (Johnson and Johnson Surgical Vision). There were 21 patients (42 eyes) in each group. The primary outcome was reading speed at high contrast and luminance. Secondary outcomes were reading speed at lower contrasts and luminances, visual acuity at all distances (distance, intermediate, and near) with and without correction, and quality of vision.

RESULTS: The reading speed at high contrast (100%) and high luminance (100%) was better in the Synergy group (P = .01). This difference between the two IOLs seemed to be preserved at lower contrasts and luminances. There was no statistically significant difference between visual acuities except for monocular uncorrected intermediate visual acuity (P = .046) in favor of the FineVision HP IOL. The mean spherical equivalents in the FineVision HP and Synergy groups were 0.14 ± 0.64 and 0.10 ± 0.33 diopters without significant difference between these means (P = .78). The defocus curve was more dome-shaped for the Synergy IOL. The evaluation of visual symptoms was comparable in both groups. The glare halo (Halometry test; Aston University) was smaller in the FineVision HP group (P = .03).

CONCLUSIONS: The Synergy IOL appears to provide better reading speed and is less sensitive to refractive error. Both lenses provided excellent distance, intermediate, and near vision. [J Refract Surg. 2022;38(7):428-434.].

PMID:35858191 | DOI:10.3928/1081597X-20220516-02

Health Lit Res Pract. 2022 Jul;6(3):e182-e190. doi: 10.3928/24748307-20220620-01. Epub 2022 Jul 8.

ABSTRACT

BACKGROUND: How individuals perceive their health literacy may differ based on demographic and individual characteristics.

OBJECTIVE: The purpose of this study was to understand the dispersion of health literacy across demographics in the state of Georgia in 2021 and to determine which factors influence health literacy.

METHODS: Study participants were age 18 years and older and completed an on-line Health Literacy Questionnaire (N = 520). The participant pool was stratified to mirror state-wide demographics of geography and race. Results were further collapsed into composite scales reflecting basic, communicative, and critical health literacy. Descriptive statistics, bivariate Pearson’s correlations, and multiple regression analyses were used. A two-step cluster analysis was performed with the nine health literacy scales.

KEY RESULTS: Rural county and no health insurance were negatively related to all three composite scales (rs = .093-.254, ps < .05). Demographic predictors accounted for 6.7% of the variance in basic (F[6, 439] = 5.287, p < .001), 10% in communicative (F[6, 438] = 8.154, p < .001), and 6% for critical (F[6, 439] = 4.675, p < .0010. In all scales, health insurance status was the strongest primary unique predictor (βs = .236, .295, .181, ps <.05, respectively). In a two-step cluster analysis only health insurance status differentiated the health literacy level clusters (X²(3) = 9.43, 34.51, ps = 024, <.001 respectively).

CONCLUSION: Lacking health insurance is the most consistent and largest contributor to low health literacy across the state of Georgia; population demographics are not. Health literacy policies and practices should be developed for universal application and not focus on specific populations. [HLRP: Health Literacy Research and Practice. 2022;6(3):e182-e190.] Plain Language Summary: In this study, demographics that are usually associated with low health literacy like age, sex, race, educational attainment, and type of county (rural or urban) were not associated with; the only significant factor was lack of health insurance. This relationship strengthens the case for universal health literacy precautions that go beyond population demographics.

PMID:35858187 | DOI:10.3928/24748307-20220620-01

Orthopedics. 2022 Jul 12:1-6. doi: 10.3928/01477447-20220706-02. Online ahead of print.

ABSTRACT

The goal of this study was to establish a normal value for, and evaluate the reliability of, a new measurement of glenoid morphologic features using magnetic resonance imaging: the anterior glenoid angle. A total of 90 magnetic resonance imaging scans of patients without shoulder arthritis were reviewed. The anterior glenoid angle of each glenoid was measured by 4 blinded physicians. The images were randomized and measured again. Finally, the Friedman angle was measured on the same images for reference. Descriptive statistics and inter- and intraclass correlation coefficients were calculated. The mean anterior glenoid angle was 60.4°±3.6°. Of the measured values, 77% were between 56° and 64°. Intraobserver reliability was very good to excellent in single measure (range, 0.763-0.901) and mean measure (range, 0.865-0.948) comparisons. Interobserver reliability was very good to excellent in both single measure (0.769) and mean measure (0.964) comparisons. The mean Friedman angle was 10.2°. Correlation between the anterior glenoid angle and Friedman angle ranged from a moderate negative (-0.496) to a strong negative correlation (-0.711) among the observers. The mean anterior glenoid angle measured via magnetic resonance imaging scan was 60.4° in normal shoulders, and more than 75% of the values were within 4° of the mean. The anterior glenoid angle has excellent inter- and intrarater reliability without using computed tomography scan or including the entire scapula in the field of view. The anterior glenoid angle has a good to very good negative correlation with the Friedman angle because decreasing anterior glenoid angles indicate increasing retroversion. [Orthopedics. 20XX;XX(X):xx-xx.].

PMID:35858179 | DOI:10.3928/01477447-20220706-02

J Neurophysiol. 2022 Jul 20. doi: 10.1152/jn.00423.2021. Online ahead of print.

ABSTRACT

Neurons are embedded in complex networks, where they participate in repetitive, coordinated interactions with other neurons. Neuronal spike timing is thus predictably constrained by a range of ionic currents that shape activity at both short (milliseconds) and longer (tens to hundreds of milliseconds) timescales, but we lack analytical tools to rigorously identify these relationships. Here, we innovate a modeling approach to test the relationship between oscillations in the local field potential (LFP) and neuronal spike timing. We use kernel density estimation to relate single neuron spike timing and the phase of LFP rhythms (in simulated and hippocampal CA1 neuronal spike trains). We then combine phase and short (3 ms) spike history information within a logistic regression framework (“phaseSH models”), and show that models that leverage refractory constraints and oscillatory phase information can effectively test whether-and the degree to which-rhythmic currents (as measured from the LFP) reliably explain variance in neuronal spike trains. This approach allows researchers to systematically test the relationship between oscillatory activity and neuronal spiking dynamics as they unfold over time and as they shift to adapt to distinct behavioral conditions.

PMID:35858125 | DOI:10.1152/jn.00423.2021

Philos Trans A Math Phys Eng Sci. 2022 Sep 5;380(2231):20210382. doi: 10.1098/rsta.2021.0382. Epub 2022 Jul 18.

ABSTRACT

This paper uses three-dimensional grain-scale finite-element (FE) simulations to appraise the classical scattering theory of plane longitudinal wave propagation in untextured polycrystals with statistically equiaxed grains belonging to the seven crystal symmetries. As revealed from the results of 10 390 materials, the classical theory has a linear relationship with the elastic scattering factor at the quasi-static velocity limit, whereas the reference FE and self-consistent (SC) results generally exhibit a quadratic relationship. As supported by the results of 90 materials, such order difference also extends to the attenuation and phase velocity, leading to larger differences between the classical theory and the FE results for more strongly scattering materials. Alternatively, two approximate models are proposed to achieve more accurate calculations by including an additional quadratic term. One model uses quadratic coefficients from quasi-static SC velocity fits and is thus symmetry-specific, while the other uses theoretically determined coefficients and is valid for any individual material. These simple models generally deliver more accurate attenuation and phase velocity (particularly the second model) than the classical theory, especially for strongly scattering materials. However, the models are invalid for the attenuation of materials with negative quadratic coefficients. This article is part of the theme issue ‘Wave generation and transmission in multi-scale complex media and structured metamaterials (part 1)’.

PMID:35858092 | DOI:10.1098/rsta.2021.0382

Clin Orthop Relat Res. 2022 Jul 19. doi: 10.1097/CORR.0000000000002326. Online ahead of print.

ABSTRACT

BACKGROUND: The subscapularis muscle, which is part of the rotator cuff, is located anterior to the shoulder. In anterior approaches to the shoulder, its supplying nerves are at risk of iatrogenic injury, which may cause postoperative complications. It is unclear whether there is any nerve-free zone in which a subscapularis split can be performed without risking nerve damage.

QUESTIONS/PURPOSES: In an anatomical study, we asked: (1) With the arm abducted 60° and externally rotated, what are the median and shortest distances between the entrance point of the subscapular nerves into subscapularis muscle and the myotendinous junction of this muscle? (2) What are those distances in other positions of the shoulder? (3) Did those measurements differ between specimen sexes or sides?

METHODS: In 84 shoulders of 66 embalmed anatomic specimens, the distance from the myotendinous junction of the subscapularis muscle to the entrance points of the subscapular nerves into the subscapularis muscle was measured using an inelastic thread and a millimeter gauge with the arm abducted 60° and rotated externally. In 16 of 84 shoulders, which were selected randomly, after taking the measurements with the arm abducted 60° and rotated externally, arm positions were changed and further measurements were taken with the arm abducted 60° and rotated neutrally, abducted 60° and rotated internally, and abducted 90° and rotated externally. The positions of the entrance points were described with statistical parameters and compared between different sides, sexes, and joint positions. Measurements were verified using eight fresh-frozen shoulders, showing no difference in distances compared with embalmed specimens and confirming reproducibility of measurements. Absolute distances were used to minimize possible distortion when using correlations and for straightforwardness and clinical applicability.

RESULTS: The median (range) distance was 43 mm (24 to 64) for the upper subscapular nerve and 38 mm (23 to 59) for the lower subscapular nerve with the arm rotated externally and abducted 60°. In the 16 subsamples, internal rotation decreased the distance to 34 mm (24 to 49) and 31 mm (15 to 43), respectively, and maximal external rotation and 90° of abduction increased it up to 49 mm (30 to 64) and 41 mm (27 to 56). Comparison of left and right sides yielded no difference. Comparison of sexes showed distances for the lower subscapular nerve of 36 mm (23 to 54) in females versus 39 mm (24 to 60) in males.

CONCLUSION: In no specimen did the nerve come closer than 23 mm medial to the myotendinous junction with the arm rotated externally and abducted. Therefore, not exceeding a distance of 20 mm medial to the myotendinous junction with the arm rotated externally seems to provide sufficient protection from nerve injury during surgery.

CLINICAL RELEVANCE: Based on the described zone of 20 mm medial to the myotendinous junction, the risk of nerve injury in a subscapularis split approach can be minimized.

PMID:35857337 | DOI:10.1097/CORR.0000000000002326