The three-dimensional (3-D) shape of erythrocytes is strongly associated with various diseases. However, conventional optical imaging approaches with Wright's staining only provide information on two-dimensional morphology. Here, we employed optical diffraction tomography (ODT), a label-free 3-D quantitative phase imaging technique, and observed uniquely shaped red blood cells (RBCs) in the peripheral blood of a patient diagnosed with myelodysplastic syndrome. Peripheral blood samples were collected when the patient visited our hospital for his two out-patient follow-ups in May 2018. The 3-D tomograms of randomly chosen RBCs were reconstructed using a commercial ODT setup. From the reconstructed 3-D RBCs, 37.5% and 32.8% of RBCs demonstrated cup-like shapes at the first and the second out-patient follow-up, respectively. Even though this is a single case report, the finding is novel and can be a potential dyserythropoietic feature found in peripheral blood.
Erythrocytes ; Follow-Up Studies ; Humans ; Myelodysplastic Syndromes ; Optical Imaging ; Outpatients ; Refractometry

PURPOSE: To compare the efficacy and complications of scleral fixation of posterior chamber intraocular lens (IOL) and retropupillary fixation of iris claw IOL for dislocated IOL or aphakia without sufficient capsular support. METHODS: This retrospective study was comprised of 17 eyes of 16 patients undergoing scleral fixation and 14 eyes of 13 patients undergoing retropupillary fixation from August 2013 to June 2018. Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), intraocular pressure (IOP), slit lamp examination, corneal topography, refractive indices, corneal curvatures, corneal endothelial cell density, and complications of both groups were examined preoperatively and 1 day, 1 week, 1 month, 2 months, and 6 months postoperatively. RESULTS: Six months after the operation, UCVA and BCVA improved in both groups; however, there were no significant differences between the two groups (UCVA, p = 0.162; BCVA, p = 0.418). IOP was temporarily higher in the scleral fixation group at one day postoperatively (p = 0.023). The mean absolute prediction error was smaller in the retropupillary iris fixation group at 6 months postoperatively (p = 0.034). Postoperative total astigmatism, corneal astigmatism, and corneal endothelial cell density were not significantly different between the two groups. CONCLUSIONS: The retropupillary iris fixation group did not show significant improvement in visual acuity compared with the scleral fixation group. However, the retropupillary iris fixation group provided better mean absolute prediction error and a low risk of postoperative increase in IOP compared with the scleral fixation group. Retropupillary fixation of iris claw IOL is a promising option for scleral fixation of posterior chamber IOL for dislocated IOL or aphakia without sufficient capsular support.
Animals ; Aphakia ; Astigmatism ; Corneal Topography ; Endothelial Cells ; Hoof and Claw ; Humans ; Intraocular Pressure ; Iris ; Lenses, Intraocular ; Refractometry ; Retrospective Studies ; Slit Lamp ; Visual Acuity

PURPOSE: To investigate the change of retinal volume according to anterior segment refractive power using contact lens by spectral domain optical coherence tomography (SD-OCT). METHODS: The retinal volume was measured using a SD-OCT (Heidelberg retinal angiography Spectralis + OCT, Heidelberg Engineering, Heidelberg, Germany) in 60 subjects without any underlying disease. The same examiner performed a 31-section macular volume-scan at 240 µm intervals, re-measured the same area by changing the refractive power of the anterior segment by wearing soft contact lenses of +6.0 diopters and −6.0 diopters. By using the ImageJ software to calculate the cross-sectional area and of the cross-sectional area and the volume was measured. RESULTS: The mean age of the participants was 25.6 ± 1.5 years and the mean axial length was 25.7 ± 1.57 mm. The volume of the posterior pole retina measured without the contact lens was 13.48 ± 0.05 and the mean volume of the retina measured with +6.0 diopter and −6.0 diopter contact lens in the same patient was 13.47 ± 0.07 mm³ and 13.48 ± 0.05 respectively. The mean volume was significantly lower(p = 0.036) in the measurement with the +6.0 diopter lens than in the measurement without the lens, and the mean volume was significantly higher in the measurement with the +6.0 diopter lens (p = 0.042). The change in retinal thickness was increased with longer axial length (r = 0.32, p < 0.05), but the central foveal thickness did not correlate with anterior corneal power (p = 0.463). CONCLUSIONS: The volume of the retina measured using the SD-OCT is affected by the refractive power of the anterior segment and the axial length. Therefore, it is necessary to consider the change of refractive index because it can change the retinal volume measured by SD-OCT.
Angiography ; Contact Lenses, Hydrophilic ; Humans ; Refractometry ; Retina ; Retinaldehyde ; Tomography, Optical Coherence

PURPOSE: In this study, three bioceramic materials, [IPS Empress CAD (Ivoclar), IPS e.max CAD (Ivoclar), and Lava Ultimate CAD (3M ESPE)] were treated with three commercial mouthrinses [Listerine, Tantum Verde, and Klorhex]; and changes in colour reflectance and surface roughness values were then quantitatively assessed. MATERIALS AND METHODS: One hundred and twenty ceramic samples, with dimensions of 2 × 12 × 14 mm, were prepared and divided into nine sample groups, except three control samples. The samples were immersed in the mouthrinse solutions for 120 hrs, and changes in colour reflectance and surface roughness values were measured by UV light spectrophotometry (Vita Easyshade; VITA Zahnfabrik) and by profilometer device (MitutoyoSurftest SJ-301), respectively. The change of surface roughness was inspected by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). RESULTS: There was a positive correlation between the ΔE and increase in the surface roughness. Two of the ceramic materials, IPS Empress and Lava Ultimate, were affected significantly by the treatment of the mouthrinse solutions (P<.05). The most affecting solution was Tantum Verde and the most affected material was Lava Ultimate. As expected, the most resistant material to ΔE and chemical corrosion was IPS e max CAD among the materials used. CONCLUSION: This work implied that mouthrinse with lower alcohol content had less deteriorating effect on colour and on the surface morphology of the bioceramic materials.
Benzydamine ; Ceramics ; Corrosion ; Microscopy, Atomic Force ; Microscopy, Electron, Scanning ; Refractometry ; Spectrophotometry ; Ultraviolet Rays

PURPOSE: To compare the accuracy of different power-calculation formulas in predicting the postoperative refraction of three-piece and one-piece intraocular lenses (IOL). METHODS: We retrospectively reviewed the medical records of 74 eyes (62 patients) that had undergone cataract surgery involving implantation of one of two IOLs―the SENSAR® AAB00 1-Piece Acrylic IOL (44 eyes), or the Hoya® VA60BB 3-Piece Acrylic IOL (30 eyes)―between October 2014 and March 2015. Axial length was measured using an optical low-coherence refractometry (Lenstar®), and biometry was then calculated by the pre-installed Lenstar program, which used the SRK/II, Sanders-Retzlaff-Kraff/Theoretical (SRK/T), and Hoffer Q formulas. Mean absolute error (MAE) and mean numeric error (MNE) were measured 1 day, 1 week, 1 month, and 2 months after surgery. RESULTS: Using the SRK/T and Hoffer Q formulas, the one-piece IOL group differed significantly from the three-piece IOL group in terms of the MNE obtained 1 month and 2 months after surgery. Across all formulas and time points, there were no significant differences between the groups in terms of MAE. CONCLUSIONS: There was no significant difference between the different power-calculation formulas. Starting 1 month after surgery, the three-piece IOL group showed myopic postoperative refraction compared to the predictive spherical equivalent using the SRK/T and Hoffer Q formulas.
Biometry ; Cataract ; Lenses, Intraocular* ; Medical Records ; Refractometry ; Retrospective Studies

PURPOSE: To examine the relationship between the refractive astigmatism by automated refractometry and the corneal astigmatism by a dual Scheimpflug analyzer in pseudophakic eyes. METHODS: Prospectively, 75 patients (100 eyes) were enrolled in the present study. Refractive astigmatism was obtained by automated refraction. Corneal astigmatism was obtained using automated keratometry (ARK-530A®) and dual Scheimpflug scanning analysis (Galilei G4®). All refractive values were converted to the power vector components J0 and J45 for comparison and regression analysis of refractive versus corneal astigmatism. Bland-Altman plots were created to estimate the agreement between measurements. RESULTS: The average astigmatism from each measurement was -1.11 ± 1.44 D (refractive astigmatism from automated refraction), -0.77 ± 1.06 D (corneal astigmatism from automated keratometry), -0.93 ± 1.02 D (simulated K from Galilei G4®), and -1.11 ± 1.48 D (total corneal power from Galilei G4®). Refractive J0 and keratometric J0 were significantly correlated (r = 0.557, p ≤ 0.001), as well as the corresponding J45 values (r = 0.655, p = 0.025). Refractive astigmatism and total corneal power components were also significantly correlated (J0: r = 0.618, p ≤ 0.001; J45: r = 0.608, p = 0.04). In the Bland-Altman plots, keratometric J0 and total corneal power J0 showed the best agreement. CONCLUSIONS: The accuracy of measurements for corneal refraction and astigmatism in pseudophakic eyes is higher using the dual Scheimpflug analyzer, especially for total corneal power. This value of astigmatism can take into account the refractive astigmatism of pseudophakic eyes and can be used in evaluating postoperative corneal astigmatism.
Astigmatism ; Humans ; Prospective Studies ; Pseudophakia ; Refractometry*

OBJECTIVES: The aims of this study were to investigate the feasibility of isosorbide delivery into perilymph through the round window membrane (RWM), and to compare the intracochlear isosorbide concentration in perilymph after oral administration (PO) versus that after round window perfusion (RWP). METHODS: Sixteen male guinea pigs (32 ears) were used. Isosorbide, an osmotic diuretic, was administered via RWP or PO. First, to investigate the optimal perfusion time, perilymph sampling of scala tympani from the RWM was performed after RWP for 15, 30, or 60 minutes. Second, to compare the drug concentration after RWP versus that after PO, perilymph was aspirated at 3 and 6 hours after administration. Intracochlear concentration of isosorbide was analyzed by high-performance liquid chromatography coupled to refractive index detection. RESULTS: Isosorbide passed through the RWM into perilymph after RWP. After RWP for 15, 30, and 60 minutes, mean isosorbide concentrations in perilymph were 116.27+/-44.65, 245.48+/-112.84, and 279.78+/-186.32 mM, respectively. The intracochlear concentration after RWP for 30 minutes was higher than that after RWP for 15 minutes (P=0.043). At 3 and 6 hours after PO, isosorbide concentrations in perilymph were 28.88+/-4.69 and 12.67+/-2.28 mM, respectively. In contrast, the corresponding concentrations after RWP were 117.91+/-17.70 and 75.03+/-14.82 mM at 3 and 6 hours, respectively. Isosorbide concentrations in perilymph following RWP were significantly higher than those following PO at both 3 and 6 hours (P=0.025 and P=0.034, respectively). CONCLUSION: Isosorbide can rapidly pass through the RWM after RWP in guinea pigs, and 30 minutes of perfusion is considered to be appropriate. In addition, over a 6-hour period, RWP can deliver higher concentrations of isosorbide into perilymph than those achieved with PO.
Administration, Oral* ; Animals ; Chromatography, Liquid ; Diuretics, Osmotic ; Guinea Pigs* ; Humans ; Isosorbide* ; Male ; Membranes ; Meniere Disease ; Perfusion* ; Perilymph* ; Refractometry ; Scala Tympani

OBJECTIVES: This study examined the influence of the resin thickness on the polymerization of silorane- and methacrylate-based composites. MATERIALS AND METHODS: One silorane-based (Filtek P90, 3M ESPE) and two methacrylate-based (Filtek Z250 and Z350, 3M ESPE) composite resins were used. The number of photons were detected using a photodiode detector at the different thicknesses (thickness, 1, 2 and 3 mm) specimens. The microhardness of the top and bottom surfaces was measured (n = 15) using a Vickers hardness with 200 gf load and 15 sec dwell time conditions. The degree of conversion (DC) of the specimens was determined using Fourier transform infrared spectroscopy (FTIR). Scratched powder of each top and bottom surface of the specimen dissolved in ethanol for transmission FTIR spectroscopy. The refractive index was measured using a Abbe-type refractometer. To measure the polymerization shrinkage, a linometer was used. The results were analyzed using two-way ANOVA and Tukey's test at p < 0.05 level. RESULTS: The silorane-based resin composite showed the lowest filler content and light attenuation among the specimens. P90 showed the highest values in the DC and the lowest microhardness at all depth. In the polymerization shrinkage, P90 showed a significantly lower shrinkage than the rest two resin products (p < 0.05). P90 showed a significantly lower refractive index than the remaining two resin products (p < 0.05). CONCLUSIONS: DC, microhardness, polymerization rate and refractive index linearly decreased as specimen thickness linearly increased. P90 showed much less polymerization shrinkage compared to other specimens. P90, even though achieved the highest DC, showed the lowest microhardness and refractive index.
Composite Resins ; Ethanol ; Hardness ; Photons ; Polymerization* ; Polymers* ; Refractometry ; Spectroscopy, Fourier Transform Infrared ; Spectrum Analysis

The optical neural recording techniques are promising tools in recent years. Compared to the traditional electrophysiological recording, the optical means offer several advantages including no inclusion of electrical noise, simultaneous imaging of a large number of neurons, or selective recording from genetically-targeted neurons. Overall the optical neural recording technique comprises the intrinsic and the extrinsic optical recordings. The methods for intrinsic neural recording employ the change of optical properties in brains such as blood flow/oxygenation, cellular volume change, or refractive index change without addition of external indicators. Those properties can be detected using various optical techniques including laser Doppler flowmetry (LDF), near-infrared (NIR) spectrometer, functional optical coherence tomography (fOCT), and surface plasmon resonance (SPR). The extrinsic monitoring techniques use fluorescence signals reflecting neuronal activity via chemical or genetic modification of the neuronal cells. Two most popular activity-dependent fluorescent probes, calcium indicators and voltage-sensitive fluorescent proteins will be examined in this review. The principles, the instrumentations and in vivo applications of those optical signal measurements are described.
Brain ; Calcium ; Fluorescence ; Fluorescent Dyes ; Laser-Doppler Flowmetry ; Neurons ; Noise ; Proteins ; Refractometry ; Surface Plasmon Resonance ; Tomography, Optical Coherence

OBJECTIVES: The aim of this study was to evaluate the optical characteristics such as color and translucency changes before and after light curing, to quantify the CQ and to measure refractive indices of body and opaque shade of resin composites materials. MATERIALS AND METHODS: Resin composites used in this study were A2 body and A2 opaque shade of Esthet-X, Filtek supreme, Gradia Direct, Clearfil Majesty and Beautifil?? Color and translucency changes before and after light curing were evaluated by colorimeter, the CQ was quantified by GC-MS and refractive index changes were measured by spectroscopic ellipsometer. RESULTS: Translucency parameter (TP) was significantly increased after curing. The CQ content of body shades are higher than that of opaque shades in all resin composites. Refractive index increased after polymerization in all materials and significant difference in Deltarefractive index was found between body and opaque shade (significance level 0.05). CONCLUSIONS: For an accurate shade match, direct shade matching of resin composite should be performed by using the cured material.
Composite Resins ; Light ; Polymerization ; Polymers ; Refractometry