Publications by authors named "Tomoaki Nakamura"

80 Publications

Tumor Shrinkage by Metyrapone in Cushing Disease Exhibiting Glucocorticoid-Induced Positive Feedback.

J Endocr Soc 2021 Jun 30;5(6):bvab055. Epub 2021 Mar 30.

Division of Diabetes and Endocrinology, Akashi Medical Center Hospital, Akashi 674-0063, Japan.

Context: Paradoxical increases in serum cortisol in the dexamethasone suppression test (DST) have been rarely observed in Cushing disease (CD). Its pathophysiology and prevalence remain unclear.

Case Description: A 62-year-old woman with suspected CD showed paradoxical increases in cortisol after both 1-mg and 8-mg DST (1.95-fold and 2.52-fold, respectively). The initiation of metyrapone paradoxically decreased plasma adrenocorticotropic hormone (ACTH) levels and suppressed cortisol levels. Moreover, the pituitary tumor considerably shrank during metyrapone treatment.

Ex Vivo Experiments: The resected tumor tissue was enzymatically digested, dispersed, and embedded into Matrigel as 3D cultured cells. ACTH levels in the media were measured. In this tumor culture, ACTH levels increased 1.3-fold after dexamethasone treatment ( < 0.01) while control tumor cultures exhibited no increase in ACTH levels, but rather a 20% to 40% suppression ( < 0.05).

Clinical Study: A cross-sectional, retrospective, multicenter study that included 92 patients with CD who underwent both low-dose and high-dose DST from 2014 to 2020 was performed. Eight cases (8.7%) showed an increase in serum cortisol after both low-dose and high-dose DST.

Conclusion: This is the first report of a patient with glucocorticoid (GC)-driven positive feedback CD who showed both ACTH suppression and tumor shrinkage by metyrapone. Our cohort study revealed that 8.7% of patients with CD patients possibly possess GC-driven positive-feedback systems, thereby suggesting the presence of a new subtype of CD that is different from the majority of CD cases. The mechanisms exhibiting GC positive feedback in CD and the therapeutic approach for these patients remain to be investigated.
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http://dx.doi.org/10.1210/jendso/bvab055DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8143664PMC
June 2021

Evaluation of CorvisST biomechanical parameters and anterior segment optical coherence tomography for diagnosing forme fruste keratoconus.

Acta Ophthalmol 2020 Dec 16. Epub 2020 Dec 16.

Chukyo Eye Clinic, Nagoya, Japan.

Purpose: To investigate the utility of biomechanical property measurements using a Scheimpflug-based tonometer (SBT) and/or anterior segment optical coherence tomography (AS-OCT) for diagnosing forme fruste keratoconus (FFK).

Methods: In this retrospective interventional case series, 23 eyes with FFK of 23 consecutive patients and 52 eyes of 52 healthy volunteers who visited our keratoconus outpatient clinic were enrolled. Logistic regression analysis was conducted to determine the causal relationship between FFK diagnosis and each parameter.

Results: When only SBT was used, the corneal stiffness parameter, stiffness parameter A1 (SP-A1) and the corneal velocity at first applanation were selected as explanatory variables, and sensitivity, specificity and area under the receiver operating characteristic curve (AUROC) were 82.9%, 86.9% and 0.938, respectively. When only AS-OCT parameters were used, the posterior corneal asymmetric component and central corneal thickness were selected, and the sensitivity, specificity and AUROC were 82.6%, 94.2% and 0.893, respectively. When parameters from both methods were used, SP-A1 and the posterior corneal asymmetry component derived from Fourier analysis were selected as explanatory variables, and sensitivity, specificity and AUROC were 91.30%, 90.38% and 0.947, respectively. No significant differences in AUROC were observed between diagnoses using each device and the combination of both devices (AS-OCT versus SBT, p = 0.314; integrated parameters versus AS-OCT, p = 0.081; integrated parameters versus SBT, p = 0.234).

Conclusion: Optimization of SBT and AS-OCT parameters allowed for the diagnosis of FFK at a clinically usable level. Forme fruste keratoconus (FFK) diagnosis integrating biomechanical properties with AS-OCT showed no superiority compared to diagnosis based on a single device.
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http://dx.doi.org/10.1111/aos.14700DOI Listing
December 2020

Prediction of anterior chamber volume after implantation of posterior chamber phakic intraocular lens.

PLoS One 2020 16;15(11):e0242434. Epub 2020 Nov 16.

Chukyo Eye Clinic, Nagoya, Japan.

Purpose: To predict the anterior chamber volume (ACV) after implantable collamer lens (ICL) implantation based on ICL size and parameters of anterior segment optical coherence tomography (AS-OCT).

Design: Retrospective study.

Methods: This study included 222 eyes of 222 patients who underwent ICL implantation at Nagoya Eye Clinic. The patients were divided into two groups: prediction group, for creating the prediction equation (148 eyes, mean age: 32.11 ± 8.04 years), and verification group, for verifying the equation (74 eyes, mean age: 33.03 ± 6.74 years). The angle opening distance (AOD), anterior chamber width (ACW), ACV, anterior chamber depth, lens vault, angle-to-angle distance, angle recess area, and trabecular iris space area were calculated using AS-OCT. A stepwise multiple regression analysis was performed. After the creation of the prediction equation, its accuracy was verified in the verification group.

Results: The ACV, AOD750, ACW, and ICL size were selected as explanatory variables to predict postoperative ACV. Mean predicted (114.2 ± 21.83 mm3) and actual postoperative ACVs (116.1 ± 25.41 mm3) were not significantly different (P = 0.269); absolute error was 10.59 ± 9.13 mm3. In addition, there was high correlation between actual and predictive ACV (adjusted R2 = 0.6996, p < 0.0001). Bland-Altman plot revealed that there was no addition or proportional error between predicted and actual postoperative ACV.

Conclusion: Postoperative ACV was accurately predicted using AS-OCT parameters and ICL size. This prediction equation may be useful for making decisions regarding ICL size.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0242434PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7668562PMC
January 2021

Comparison of Corneal Biomechanical Properties and Corneal Tomography Between Customized and Accelerated Corneal Crosslinking in Eyes with Keratoconus.

Cornea 2021 Jul;40(7):851-858

Nagoya Eye Clinic, Nagoya, Japan; and.

Purpose: To compare the changes in corneal biomechanical properties and corneal tomography between transepithelial customized corneal crosslinking (C-CXL) and epithelium-off accelerated corneal crosslinking (A-CXL) in eyes with keratoconus.

Methods: Twenty eyes in 20 consecutive patients who underwent C-CXL (C-CXL group) and 20 eyes in 20 patients who underwent A-CXL (A-CXL group) were included in this retrospective comparative study. The corneal biomechanical properties were analyzed using a Scheimpflug-based tonometer, and all corneas were examined by anterior segment optical coherence tomography (AS-OCT) before and 3 months after surgery. The corneal biomechanical parameters analyzed were the maximum inverse radius, deformation amplitude (DA) ratio max (2 mm), stiffness parameter at applanation 1, and integrated radius. The AS-OCT parameters analyzed included average keratometry, corneal astigmatism, maximum keratometry reading (Kmax), higher-order irregularity, and asymmetry.

Results: In the C-CXL group, there were significant improvements in biomechanical parameters, including the maximum inverse radius, the DA ratio max (2 mm), and the integrated radius after surgery (P = 0.037, P = 0.002, and P = 0.003, respectively). In the C-CXL group, there was a significant decrease in the Kmax, higher-order irregularity, and asymmetry components (P = 0.014, P = 0.008, and P = 0.016, respectively). The biomechanical properties and AS-OCT parameters did not change significantly in the A-CXL group after surgery. According to multiple regression analyses, C-CXL had a greater effect than A-CXL in improving the maximum inverse radius, DA ratio max (2 mm), integrated radius, Kmax, asymmetry component, and higher-order irregularity component.

Conclusions: C-CXL might improve the biomechanical properties and irregular shape of the cornea from the early postoperative period to a greater extent than A-CXL.
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http://dx.doi.org/10.1097/ICO.0000000000002572DOI Listing
July 2021

Long-term In Vivo Stability of Posterior Chamber Phakic Intraocular Lens: Properties and Light Transmission Characteristics of Explants.

Am J Ophthalmol 2020 11 2;219:295-302. Epub 2020 Jul 2.

Chukyo Eye Clinic, Nagoya, Japan.

Purpose: To evaluate the in vivo durability of the surface and optical properties of the implantable Collamer lens (ICL).

Design: Retrospective case series.

Methods: We included patients who developed cataracts after having undergone ICL implantation from March 2003 to May 2014 and underwent ICL explantation followed by cataract surgery from March 2017 to December 2019 at the Nagoya Eye Clinic. ICL explants were submitted to Chukyo Medical Co, Ltd (Nagoya City, Japan) for laboratory analysis using ultraviolet-visible light spectroscopy, light microscopy (LM), and scanning electron microscopy. Patients' demographic and clinical data were collected and reviewed.

Results: Thirteen eyes from 10 patients were studied. The average age at ICL explantation was 50.5 ± 8.5 years (range, 34.5-66.3 years). The average length of ICL stay in the eye (from implantation to explantation) was 10.5 ± 2.7 years (range, 4.4-13.7 years). No opacification or coloring of the ICL explants was observed by LM. The ICL explants showed almost the same light transmittance as that of unused ICLs. Scanning electron microscopy revealed no irregularities at the surface of the center and periphery of the optic and haptic footplate. The positioning holes did not show any deposition.

Conclusion: The ICLs remained in-eye for >10 years without any deterioration in the surface and optical properties of the ICL, despite their contact with the ciliary body and iris tissues and the continuous interaction with the aqueous humor components. The present study shows long-term in vivo stability of the ICL.
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http://dx.doi.org/10.1016/j.ajo.2020.06.025DOI Listing
November 2020

Optimization of implantable collamer lens sizing based on swept-source anterior segment optical coherence tomography.

J Cataract Refract Surg 2020 May;46(5):742-748

From the Nagoya Eye Clinic (Nakamura, Isogai, Yoshida, Sugiyama), Nagoya, Japan; Department of Ophthalmology, Keio University School of Medicine (Kojima), Tokyo, Japan.

Purpose: To optimize the implantable collamer lens (ICL) sizing method using anterior segment optical coherence tomography (AS-OCT).

Setting: Nagoya Eye Clinic, Nagoya, Japan.

Design: Interventional case series.

Methods: A stepwise multiple regression analysis was performed using the optimal ICL size as a dependent variable and preoperative AS-OCT parameters as explanatory variables for 81 eyes of 41 patients, and the NK-formula version 2 (NK-formula V2) was obtained. Thereafter, 68 eyes of 42 patients were implanted with the ICLs selected as closest to the optimal ICL size calculated by the NK-formula V2. At 3 months postoperatively, the achieved vault was measured by AS-OCT to evaluate the optimization of the sizing method.

Results: The anterior chamber width (ACW) and crystalline lens rise were selected as significant parameters for the regression model (R = 0.61, P < .001), as with the previous NK-formula. Of the 68 eyes, 36 patients/62 eyes (91.2%), 5 patients/5 eyes (7.3%), and 1 patient/1 eye (1.5%) were in the moderate, high, and low vault categories, respectively. In the 68 eyes, the vault showed no correlation with the optimal ICL size (R = 0.0185, P = .269), whereas the vault showed a negative correlation with the optimal ICL size in both the 12.6 mm ICL subgroup (R = -0.409, P = .0088) and the 13.2 mm ICL subgroup (R = -0.818, P = .0013).

Conclusions: This optimization approach showed excellent ability to select an appropriate ICL to be implanted regardless of the value of other ocular parameters and age, except ACW.
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http://dx.doi.org/10.1097/j.jcrs.0000000000000134DOI Listing
May 2020

Regulation of miR-1-Mediated Connexin 43 Expression and Cell Proliferation in Dental Epithelial Cells.

Front Cell Dev Biol 2020 17;8:156. Epub 2020 Mar 17.

Division of Molecular Pharmacology and Cell Biophysics, Department of Oral Biology, Tohoku University Graduate School of Dentistry, Sendai, Japan.

Many genes encoding growth factors, receptors, and transcription factors are induced by the epithelial-mesenchymal interaction during tooth development. Recently, numerous functions of microRNAs (miRNAs) are reportedly involved in organogenesis and disease. miRNAs regulate gene expression by inhibiting translation and destabilizing mRNAs. However, the expression and function of miRNAs in tooth development remain poorly understood. This study aimed to analyze the expression of miRNAs produced during tooth development using a microarray system to clarify the role of miRNAs in dental development. miR-1 showed a unique expression pattern in the developing tooth. miR-1 expression in the tooth germ peaked on embryonic day 16.5, decreasing gradually on postnatal days 1 and 3. An hybridization assay revealed that miR-1 is expressed at the cervical loop of the dental epithelium. The expression of miR-1 and connexin (Cx) 43, a target of miR-1, were inversely correlated both and . Knockdown of miR-1 induced the expression of Cx43 in dental epithelial cells. Interestingly, cells with miR-1 downregulation proliferated slower than the control cells. Immunocytochemistry revealed that Cx43 in cells with miR-1 knockdown formed both cell-cell gap junctions and hemichannels at the plasma membrane. Furthermore, the rate of ATP release was higher in cells with miR-1 knockdown than in control cells. Furthermore, Cx43 downregulation in developing molars was observed in Epiprofin-knockout mice, along with the induction of miR-1 expression. These results suggest that the expression pattern of Cx43 is modulated by miR-1 to control cell proliferation activity during dental epithelial cell differentiation.
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http://dx.doi.org/10.3389/fcell.2020.00156DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7089876PMC
March 2020

Keratoconus Screening Using Values Derived From Auto-Keratometer Measurements: A Multicenter Study.

Am J Ophthalmol 2020 07 28;215:127-134. Epub 2020 Feb 28.

Department of Ophthalmology, Japan Community Health Care Organization, Chukyo Hospital, Nagoya, Japan; Chukyo Eye Clinic, Nagoya, Japan.

Purpose: Screening of early-stage keratoconus using auto-keratometer parameters.

Design: Evaluation of a screening approach.

Methods: At 5 major centers in Japan, we enrolled 123 eyes of 123 patients with Amsler-Krumeich classification stage 1 (<50 years of age [average 26.36 ± 8.68 years]; 84/39 male/female) and 205 eyes of 205 healthy subjects (average age 26.20 ± 7.34 years, 139/66 male/female). Participants were divided 2:1 into a prediction group and an application group. In the prediction group, multivariate logistic regression analysis was performed with keratoconus diagnosis as the dependent variable, and auto-keratometer parameters including average K, steep K, flat K, astigmatism, and astigmatic axis (no, with-the-rule, against-the-rule, and oblique) as independent variables. The diagnostic probability determined by regression analysis was defined as the keratometer keratoconus index. The cutoff value was determined from the receiver operating characteristic curve. This prediction equation was evaluated in the application group. Our primary outcome measure was the accuracy of the prediction equation for discriminating keratoconus from normal eyes.

Results: The selected explanatory variables were steep K (partial regression coefficient [β] 1.284, odds ratio [OR] 3.610), flat K (β -0.618, OR 0.539), and with-the-rule astigmatism (β -3.163, OR 0.042). The area under the receiver operating characteristic curve of keratometer keratoconus index was 0.90, which was significantly better than individual parameters (P < .001). The sensitivity and specificity values in the application group were 85.0% and 86.7%, respectively.

Conclusions: Although the sensitivity/specificity was not high, the new prediction equation using auto-keratometer-derived parameters enabled better discrimination of early-stage keratoconus than the isolated parameters.
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http://dx.doi.org/10.1016/j.ajo.2020.02.017DOI Listing
July 2020

Evaluation of Biomechanically Corrected Intraocular Pressure Measurements in Keratoconus and Forme Fruste Keratoconus.

Ophthalmic Res 2020 28;63(6):541-549. Epub 2020 Feb 28.

Nagoya Eye Clinic, Nagoya, Japan.

Introduction: Although biomechanically corrected intraocular pressure (bIOP) is available, the effectiveness of intraocular pressure (IOP) correction in keratoconus and forme fruste keratoconus (FFK) eyes has not been investigated.

Objective: Evaluation of bIOP measurements in eyes with keratoconus and FFK.

Methods: Forty-two eyes in 21 patients with keratoconus in one eye and FFK in the fellow eye were examined (KC/FFK group; mean age 24.62 ± 8.6 years; 16 males and 5 females). The control group consisted of 62 eyes in 31 unaffected subjects (mean age 26.26 ± 3.64 years; 15 males and 16 females). The bIOP was determined using a Scheimpflug-based tonometer (Corvis Scheimpflug Technology [Corvis ST®]) after measuring the IOP with a conventional non-contact tonometer (NIOP). The agreement between NIOP and bIOP values was examined using the Bland-Altman plot. The difference between NIOP and bIOP (bIOP correction amount) was compared between keratoconus and FFK eyes.

Results: In the control group, there were no significant differences between right and left eyes in both NIOP and bIOP values (p = 0.975 and p = 0.224, respectively). In the KC/FFK group, NIOP values were significantly lower in the keratoconus eyes (9.93 ± 1.96 mm Hg) than in the FFK eyes (12.23 ± 3.03 mm Hg; p = 0.0003). There was no significant difference in bIOP values between the right and left eyes of the KC/FFK group (p = 0.168). The bIOP correction amount was significantly increased in keratoconus eyes (3.58 ± 2.12 mm Hg) compared to in FFK eyes (1.80 ± 3.32 mm Hg; p = 0.011).

Conclusions: For eyes with keratoconus and FFK, the bIOP method is effective to adjust IOP measurements based on corneal biomechanical properties.
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http://dx.doi.org/10.1159/000506839DOI Listing
February 2020

Relation between HOMA-IR and insulin sensitivity index determined by hyperinsulinemic-euglycemic clamp analysis during treatment with a sodium-glucose cotransporter 2 inhibitor.

Endocr J 2020 May 6;67(5):501-507. Epub 2020 Feb 6.

Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan.

We had aimed to determine whether homeostasis model assessment-insulin resistance (HOMA-IR) reflects insulin resistance-sensitivity during treatment with a sodium-glucose cotransporter 2 inhibitor (SGLT2i). Hyperinsulinemic-euglycemic clamp analysis was performed in 22 patients with type 2 diabetic patients taking dapagliflozin (5 mg/day before or after breakfast). Propensity score matching of these individuals (SGLT2i group) for age, sex, body mass index, and clamp-derived tissue glucose uptake rate with 44 type 2 diabetic patients who had undergone clamp analysis without SGLT2i treatment (control group) identified 17 paired subjects in each group for further analysis of the relation between HOMA-IR and a clamp-derived insulin sensitivity index (ISI). Natural log-transformed HOMA-IR was negatively correlated with ISI in both SGLT2i (r = -0.527, p = 0.030) and control (r = -0.534, p = 0.027) groups. The simple regression lines for log-transformed HOMA-IR and ISI in the two groups showed similar slopes but differed in their intercepts. Multivariate analysis revealed that HOMA-IR for patients with the same ISI in the two groups was related by the formula: HOMA-IR = HOMA-IR × 2.45. In conclusion, HOMA-IR was well correlated with ISI during SGLT2i treatment, but values corresponding to the same ISI were lower in the SGLT2i group than in the control group.
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http://dx.doi.org/10.1507/endocrj.EJ19-0445DOI Listing
May 2020

HVGH: Unsupervised Segmentation for High-Dimensional Time Series Using Deep Neural Compression and Statistical Generative Model.

Front Robot AI 2019 20;6:115. Epub 2019 Nov 20.

Center for Mathematical Modeling and Data Science, Osaka University, Osaka, Japan.

Humans perceive continuous high-dimensional information by dividing it into meaningful segments, such as words and units of motion. We believe that such unsupervised segmentation is also important for robots to learn topics such as language and motion. To this end, we previously proposed a hierarchical Dirichlet process-Gaussian process-hidden semi-Markov model (HDP-GP-HSMM). However, an important drawback of this model is that it cannot divide high-dimensional time-series data. Furthermore, low-dimensional features must be extracted in advance. Segmentation largely depends on the design of features, and it is difficult to design effective features, especially in the case of high-dimensional data. To overcome this problem, this study proposes a hierarchical Dirichlet process-variational autoencoder-Gaussian process-hidden semi-Markov model (HVGH). The parameters of the proposed HVGH are estimated through a mutual learning loop of the variational autoencoder and our previously proposed HDP-GP-HSMM. Hence, HVGH can extract features from high-dimensional time-series data while simultaneously dividing it into segments in an unsupervised manner. In an experiment, we used various motion-capture data to demonstrate that our proposed model estimates the correct number of classes and more accurate segments than baseline methods. Moreover, we show that the proposed method can learn latent space suitable for segmentation.
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http://dx.doi.org/10.3389/frobt.2019.00115DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7805757PMC
November 2019

Relationship between glycated hemoglobin level and duration of hypoglycemia in type 2 diabetes patients treated with sulfonylureas: A multicenter cross-sectional study.

J Diabetes Investig 2020 Mar 17;11(2):417-425. Epub 2019 Sep 17.

Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan.

Aims/introduction: Sulfonylurea-related hypoglycemia increases the risk of cardiovascular sequela, such as cardiac arrhythmia. This study aimed to clarify the relationship between the level of glycated hemoglobin (HbA ) and the duration of hypoglycemia in type 2 diabetes patients treated with sulfonylureas.

Materials And Methods: Glucose levels in the enrolled patients (n = 300) were investigated with a professional continuous glucose monitoring device in the outpatient setting at six diabetes centers in Japan.

Results: A total of 269 participants completed the study. The duration of hypoglycemia with glucose values of <54 mg/dL was significantly longer in patients with an HbA level of ≤6.4% than in those with an HbA level of ≥8.0%, and that of hypoglycemia with glucose values of <70 mg/dL was significantly longer in patients with an HbA level of ≤6.4%, 6.5-6.9% or 7.0-7.4% than in those with an HbA level of ≥8.0%. Patients with an HbA level of ≤6.4% were exposed to glucose values of <70 mg/dL for >10% of the time in daily life (6.8 ± 5.6 min/h). The duration of hypoglycemia with glucose values of <70 mg/dL was longer at night than during the daytime, and the nadir of glucose values occurred between 03.00 and 05.00 hours irrespective of HbA level. The duration of hypoglycemia was associated with the duration of diabetes and sulfonylurea dose.

Conclusions: The duration of hypoglycemia was inversely correlated with HbA level and was longer during the night-time than daytime in type 2 diabetes patients treated with sulfonylureas.
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http://dx.doi.org/10.1111/jdi.13132DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7078100PMC
March 2020

Prediction of Best-Corrected Visual Acuity With Swept-Source Optical Coherence Tomography Parameters in Keratoconus.

Cornea 2019 Sep;38(9):1154-1160

Department of Ophthalmology, Nagoya Eye Clinic, Nagoya, Japan.

Purpose: This study aimed to predict the best-corrected visual acuity (BCVA) based on swept-source optical coherence tomography (SS-OCT) parameters in eyes with keratoconus.

Methods: We retrospectively reviewed 135 eyes of 135 patients with keratoconus (mean age: 31.9 ± 12.4 years). The average keratometry value and BCVA (logarithm of the minimal angle of resolution [Snellen]) were 48.68 ± 5.44 diopter and 0.20 ± 0.36 (20/25), respectively. Eleven parameters were calculated using SS-OCT. Apart from the corneal height and elevation, all the other parameters were calculated from both anterior and posterior corneal OCT data. The patients were divided into 2 groups, 1 for creating the prediction equation (prediction group, 86 eyes) and another for verifying the equation (verification group, 49 eyes). In the former, individual correlations between the BCVA and SS-OCT parameters were analyzed. A stepwise multiple regression analysis was performed with the BCVA as a dependent variable and SS-OCT parameters as independent variables. After its creation, the accuracy of the prediction equation was verified in the verification group.

Results: All the parameters, except for age and total corneal cylinder, showed statistically significant correlations with BCVA (P < 0.0001). Using the stepwise multiple regression analysis, we selected 2 explanatory variables: root mean square of anterior corneal elevation (standardized regression coefficient: 1.221; P < 0.0001) and total coma aberration (standardized regression coefficient: -0.575; P = 0.001; adjusted R = 0.546). The prediction was correct in 84.6% of the eyes within ±1 line of Snellen BCVA.

Conclusions: Using the equation we derived from SS-OCT parameters is a promising method to predict visual function in patients with keratoconus.
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http://dx.doi.org/10.1097/ICO.0000000000002043DOI Listing
September 2019

Posterior Chamber Phakic Intraocular Lens Implantation for the Correction of Myopia and Myopic Astigmatism: A Retrospective 10-Year Follow-up Study.

Am J Ophthalmol 2019 10 10;206:1-10. Epub 2019 May 10.

Nagoya Eye Clinic, Nagoya, Japan.

Purpose: To assess the 10-year clinical outcomes of implantable collamer lens (ICL) implantation for myopia and astigmatism.

Design: Retrospective observational case series.

Methods: This study included 114 eyes of 61 patients who underwent ICL implantation for correction of myopia and myopic astigmatism. We assessed the safety, efficacy, predictability, stability, and adverse events preoperatively, at 6 months (106 eyes) and 1 (94 eyes), 3 (58 eyes), 5 (65 eyes), 8 (89 eyes), and 10 (70 eyes) years postoperatively. Only the eyes with clinical data available at each follow-up time were analyzed.

Results: The mean logMAR uncorrected and corrected distance visual acuities were -0.01 ± 0.24 and -0.18 ± 0.07 at 10 years postsurgery. The mean indices for safety and efficacy were 0.88 ± 0.15 and 0.66 ± 0.26, respectively. At 10 years postsurgery, 71.4% and 87.1% of the eyes were within 0.5 and 1.0 diopters (D), respectively, of the attempted spherical equivalent correction. The mean intraocular pressure was 13.1 ± 2.4 mmHg preoperatively and 13.1 ± 2.9 mmHg at 10 years postoperatively. The mean endothelial cell loss was 5.3% at 10 years postsurgery. Twelve of 114 eyes (10.5%) developed anterior subcapsular cataract during 5-10 years' follow-up; among these, 4 eyes (3.5%) were symptomatic and ICL explantation and phacoemulsification surgery were performed. No vision-threatening complications occurred during the observation period.

Conclusion: ICL implantation offered good overall outcomes in all measures of safety, efficacy, predictability, and stability for the correction of myopia and myopic astigmatism throughout a long-term follow-up period of 10 years.
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http://dx.doi.org/10.1016/j.ajo.2019.04.024DOI Listing
October 2019

Recurrent prolapse of toric implantable collamer lens after blunt ocular trauma under mesopic conditions.

Clin Case Rep 2019 Apr 17;7(4):626-629. Epub 2019 Feb 17.

Department of Ophthalmology Keio University School of Medicine Tokyo Japan.

Implantable collamer lenses (ICL) carry a risk of prolapse caused by direct ocular trauma, especially in mesopic conditions and when oversized ICLs are implanted. We recommend early surgical repositioning, as well as patient education that encourages goggle use during active sports.
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http://dx.doi.org/10.1002/ccr3.2055DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6452523PMC
April 2019

A Multicenter Study on Early Outcomes of Small-Incision Lenticule Extraction for Myopia.

Sci Rep 2019 03 11;9(1):4067. Epub 2019 Mar 11.

Shinjuku Kinshi Clinic, Tokyo, Japan.

This study was aimed to investigate the early clinical outcomes of small-incision lenticule extraction (SMILE) to correct both myopia and myopic astigmatism at major clinical centers in Japan. This case series consisted of two hundred fifty-two eyes of 130 consecutive patients who underwent SMILE surgery (29.5 ± 6.3 years, mean age ± standard deviation), with spherical equivalents of -4.33 ± 1.61 D. We determined the safety, efficacy, predictability, stability, and adverse events of this procedure. Corrected distance visual acuity significantly improved, from -0.18 ± 0.04 preoperatively to -0.19 ± 0.07 logMAR postoperatively (paired t-test, p < 0.001). Uncorrected distance visual acuity also significantly improved, from 1.05 ± 0.26 preoperatively to -0.15 ± 0.11 logMAR postoperatively (p < 0.001). 88% and 98% of eyes were within ± 0.5 and 1.0 D of the targeted correction, respectively. Changes in manifest spherical equivalent from 1 week postoperatively were 0.02 ± 0.35 D (p = 0.127). No vision-threatening complications were observed in any of the cases. SMILE performed well in the correction of myopic refractive errors, and we experienced no severe complications in this series, indicating its feasibility as a surgical option for the treatment of these eyes.
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http://dx.doi.org/10.1038/s41598-019-40805-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6411974PMC
March 2019

Effect of switching from conventional continuous subcutaneous insulin infusion to sensor augmented pump therapy on glycemic profile in Japanese patients with type 1 diabetes.

Diabetol Int 2018 Jul 22;9(3):201-207. Epub 2018 Jan 22.

1Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017 Japan.

Aims: Evidence suggests that sensor augmented pump (SAP) therapy is superior to conventional continuous subcutaneous insulin infusion (CSII) for achieving glycemic control in patients with type 1 diabetes. However, the clinical benefit of SAP therapy in East Asians has not yet been demonstrated.

Methods: The effect of switching from conventional CSII to SAP therapy on glycemic profile was examined in 18 Japanese patients with type 1 diabetes. The glycemic profile of the patients was determined by retrospective continuous glucose monitoring (CGM) within 1 month before the treatment switch, whereas that at 6 and 12 months after the switch was evaluated with the CGM function of the SAP device. Hemoglobin A1c levels were also measured before and after the switch to SAP therapy.

Results: The duration of hypoglycemia was significantly decreased at both 6 and 12 months after the change in treatment (6.6 ± 4.5, 3.2 ± 4.1, and 3.0 ± 2.8 min/h for before and 6 and 12 months, respectively), as was the HbA1c level at 12 months (7.8 ± 1.0 and 7.4 ± 0.9%, respectively). The duration of hyperglycemia did not differ between before and after the treatment switch. The decline in HbA1c level at 12 months after the switch to SAP was negatively correlated with age.

Conclusion: Switching from conventional CSII to SAP therapy was associated with a decrease in both the duration of hypoglycemia and the level of HbA1c in Japanese patients with type 1 diabetes.
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http://dx.doi.org/10.1007/s13340-018-0344-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6224909PMC
July 2018

Effects of exenatide and liraglutide on postchallenge glucose disposal in individuals with normal glucose tolerance.

Endocrine 2019 04 8;64(1):43-47. Epub 2018 Nov 8.

Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan.

Purpose: Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are categorized as short- or long-acting types, but information regarding differences in the effects of these two types on postprandial glucose disposal has been limited. We have now investigated the effects of exenatide and liraglutide (short- and long-acting GLP-1RAs, respectively) on glucose disposal during an oral glucose tolerance test (OGTT).

Methods: Fourteen healthy volunteers with normal glucose tolerance underwent three OGTTs, which were performed without pharmacological intervention or after a single administration of exenatide or liraglutide at 30 min and 10 h, respectively, before test initiation. The three OGTTs were performed with intervals of at least 7 days between successive tests and within a period of 2 months.

Results: Exenatide, but not liraglutide, markedly decelerated the peak of both plasma glucose and serum insulin levels during the OGTT, with the peaks of both glucose and insulin concentrations occurring at 150 min after test initiation with exenatide compared with 30 min in the control condition or with liraglutide. Exenatide and liraglutide reduced the area under the curve for plasma glucose levels during the OGTT by similar extents, whereas that for serum insulin levels was reduced only by exenatide.

Conclusions: Our results suggest that exenatide decelerates the increase in plasma glucose levels through inhibition of glucose absorption and that it exerts an insulin-sparing action after glucose challenge.
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http://dx.doi.org/10.1007/s12020-018-1808-9DOI Listing
April 2019

Effects of Insulin Degludec and Insulin Glargine U300 on Day-to-Day Fasting Plasma Glucose Variability in Individuals with Type 1 Diabetes: A Multicenter, Randomized, Crossover Study (Kobe Best Basal Insulin Study 2).

Diabetes Ther 2018 Dec 19;9(6):2399-2406. Epub 2018 Oct 19.

Division of Diabetes and Endocrinology Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan.

Introduction: Administered basal insulin markedly influences the fasting plasma glucose (FPG) level of individuals with type 1 diabetes. Insulin degludec (IDeg) and insulin glargine U300 (IGlar U300) are now available as ultra-long-acting insulin formulations, but whether or how their glucose-stabilizing effects differ remains unclear. We will compare the effects of these basal insulins on parameters related to blood glucose control, with a focus on day-to-day glycemic variability, in individuals with type 1 diabetes treated with multiple daily injections.

Methods: A multicenter, randomized, open-label, crossover, comparative study (Kobe Best Basal Insulin Study 2) will be performed at 13 participating institutions in Japan. A total of 46 C-peptide-negative adult outpatients with type 1 diabetes will be randomly assigned 1:1 by a centralized allocation process to IGlar U300 (first period)/IDeg (second period) or IDeg (first period)/IGlar U300 (second period) groups, in which subjects will be treated with the corresponding basal insulin for consecutive 4-week periods. The basal insulin will be titrated to achieve an FPG of less than 130 mg/dL initially and then less than 110 mg/dL if feasible. In the last week of each period, plasma glucose will be determined seven times a day by self-monitoring of blood glucose (SMBG) and intraday and day-to-day glucose excursions will be determined by flash glucose monitoring (FGM). The primary end point is comparison of day-to-day glycemic variability as evaluated by the standard deviation (SD) of FPG during the last week of each treatment period. Secondary end points include the coefficient of variance of FPG, the frequency of severe hypoglycemia as evaluated by SMBG, the duration of hypoglycemia as evaluated by FGM, intraday glycemic variability calculated from both SMBG and FGM data, and the administered insulin dose.

Planned Outcomes: The results of the study will be submitted for publication in a peer-reviewed journal to report differences in the effects of two ultra-long-acting basal insulins, IDeg and IGlar U300.

Conclusion: This head-to-head comparison will be the first study to compare the effects of IDeg and IGlar U300 on day-to-day FPG variability in C-peptide-negative individuals with type 1 diabetes.

Trial Registration: Registered in University Hospital Medical Information Network (UMIN) Clinical Trials Registry as 000029630 on 20 June 2017.

Funding: Novo Nordisk Pharma Ltd.
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http://dx.doi.org/10.1007/s13300-018-0523-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6250619PMC
December 2018

Prospective Randomized Multicenter Comparison of the Clinical Outcomes of V4c and V5 Implantable Collamer Lenses: A Contralateral Eye Study.

J Ophthalmol 2018 5;2018:7623829. Epub 2018 Sep 5.

Department of Ophthalmology, Sanno Hospital, Tokyo, Japan.

Purpose: To compare the visual and refractive outcomes and night vision performance questionnaire results between V4c and V5 implantable Collamer lenses in a prospective, randomized, multicenter study.

Settings: Four refractive surgery centers.

Design: Prospective randomized multicenter single-masked comparative study.

Methods: Twenty-three patients were enrolled in this study. A conventional V4c model (EVO Visian ICL) was implanted in one eye, and a V5 model (EVO+ Visian ICL), which has a larger optic diameter than the V4c model, was implanted in the contralateral eye. The uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA) were evaluated before and 6 months after surgery. At 6 months after surgery, a questionnaire on night vision disturbances was administered. The efficacy, safety, and predictability of the two implanted ICL models were compared.

Results: There were no significant differences in the postoperative UDVA and CDVA between the two ICL models. The mean efficacy indexes for the V4c and V5 lenses were 1.16 ± 0.22 and 1.03 ± 0.23, respectively. The mean safety indexes of the V4c and V5 lenses were 1.21 ± 0.20 and 1.19 ± 0.20, respectively. The night vision performance questionnaire revealed that 7 patients (37%) noticed a difference in visual performance between the eyes, and all of them reported that they could see better at night with the V5-implanted eye compared with the V4c-implanted eye.

Conclusion: The V4c and V5 ICL models achieved similar visual and refractive outcomes, whereas the V5 model showed a possible advantage in reducing night vision disturbances.
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http://dx.doi.org/10.1155/2018/7623829DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6145048PMC
September 2018

Comprehensive Evaluation of Combination Therapy with Basal Insulin and Either Lixisenatide or Vildagliptin in Japanese Patients with Type 2 Diabetes: A Randomized, Open-Label, Parallel-Group, Multicenter Study.

Diabetes Ther 2018 Oct 11;9(5):2067-2079. Epub 2018 Sep 11.

Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan.

Introduction: We comprehensively evaluated the effects of combination therapy with insulin glargine and the incretin-based drugs lixisenatide or vildagliptin in Japanese patients with type 2 diabetes.

Methods: In this 12-week, randomized, open-label, parallel-group, multicenter study (GLP-ONE Kobe), the incretin-based drug sitagliptin was randomly switched to lixisenatide (20 μg/day, n = 18) or vildagliptin (100 mg/day, n = 20) in patients with inadequate glycemic control despite combination therapy with insulin glargine and sitagliptin. The dose of insulin glargine was titrated after the switch to maintain fasting blood glucose at approximately 110 mg/dL. The primary end points of the study were the change in glycosylated hemoglobin (HbA) level between before and 12 weeks after the treatment switch, the proportion of patients achieving an HbA level below 7.0%, and the postprandial increase in glucose concentration as assessed by self-monitoring of blood glucose.

Results: The change in HbA level from baseline to 12 weeks did not differ significantly between the lixisenatide and vildagliptin groups (- 0.6 ± 0.7% and - 0.6 ± 1.2%, respectively, P = 0.920). Neither the proportion of patients achieving an HbA level below 7.0% nor the postprandial increase in glucose concentration was different between two groups. Body weight and serum low density lipoprotein (LDL) cholesterol level decreased significantly in the lixisenatide and vildagliptin groups, respectively. Both drugs were associated with mild gastrointestinal symptoms but not with severe hypoglycemia. Vildagliptin was associated with elevation of serum aspartate transaminase. Treatment satisfaction as assessed with the Diabetes Treatment Satisfaction Questionnaire did not differ significantly between the two groups.

Conclusion: The combinations of basal insulin and either lixisenatide or vildagliptin have similar efficacies with regard to improvement of glycemic control.

Trial Registration: This trial has been registered with UMIN (No. 000010769).
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http://dx.doi.org/10.1007/s13300-018-0505-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6167300PMC
October 2018

Posterior Chamber Phakic Intraocular Lens Implantation in Eyes with an Anterior Chamber Depth of Less Than 3 mm: A Multicenter Study.

Sci Rep 2018 09 6;8(1):13322. Epub 2018 Sep 6.

Chukyo Hospital, Aichi, Nagoya, Japan.

This study was aimed to assess the clinical outcomes of Visian ICL (hole ICL; STAAR Surgical, Inc.) implantation for the correction of myopic refractive errors in eyes having an anterior chamber depth (ACD) below the current manufacturer's recommendation (<3.0 mm). We comprised 365 eyes of 201 consecutive patients (mean age ± standard deviation, 35.7 ± 7.5 years) with spherical equivalents of -8.66 ± 3.54 D. We evaluated the safety, efficacy, predictability, stability, intraocular pressure (IOP), endothelial cell density (ECD), and complications. The safety and efficacy indices were 1.12 ± 0.22 and 0.98 ± 0.22. At 1 year, 90% and 98% of eyes were within ± 0.5 and 1.0 D of the attempted correction, respectively. Changes in the manifest refraction from 1 week to 1 year postoperatively were -0.08 ± 0.34 D. The mean ECD loss was 0.2 ± 8.7%. No eyes showed a significant ECD loss (≥30%). We found no significant correlation between the ACD and the change in ECD (Pearson correlation coefficient r = -0.048, p = 0.360). No significant IOP rise or vision-threatening complication occurred at any time. These findings indicate that the surgical indication of ICL implantation should be reconsidered in terms of ACD.
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http://dx.doi.org/10.1038/s41598-018-31782-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6127101PMC
September 2018

SERKET: An Architecture for Connecting Stochastic Models to Realize a Large-Scale Cognitive Model.

Front Neurorobot 2018 26;12:25. Epub 2018 Jun 26.

Department of Information Science and Engineering, Ritsumeikan University, Shiga, Japan.

To realize human-like robot intelligence, a large-scale cognitive architecture is required for robots to understand their environment through a variety of sensors with which they are equipped. In this paper, we propose a novel framework named Serket that enables the construction of a large-scale generative model and its inferences easily by connecting sub-modules to allow the robots to acquire various capabilities through interaction with their environment and others. We consider that large-scale cognitive models can be constructed by connecting smaller fundamental models hierarchically while maintaining their programmatic independence. Moreover, the connected modules are dependent on each other and their parameters must be optimized as a whole. Conventionally, the equations for parameter estimation have to be derived and implemented depending on the models. However, it has become harder to derive and implement equations of large-scale models. Thus, in this paper, we propose a parameter estimation method that communicates the minimum parameters between various modules while maintaining their programmatic independence. Therefore, Serket makes it easy to construct large-scale models and estimate their parameters via the connection of modules. Experimental results demonstrated that the model can be constructed by connecting modules, the parameters can be optimized as a whole, and they are comparable with the original models that we have proposed.
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http://dx.doi.org/10.3389/fnbot.2018.00025DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6028621PMC
June 2018

Control-matched comparison of refractive and visual outcomes between small incision lenticule extraction and femtosecond laser-assisted LASIK.

Clin Ophthalmol 2018 10;12:865-873. Epub 2018 May 10.

Nagoya Eye Clinic, Nagoya, Japan.

Purpose: This retrospective case-matched study aimed to compare visual and refractive outcomes between small incision lenticule extraction (SMILE) and LASIK.

Patients And Methods: Patients who underwent SMILE (34 eyes of 23 patients) or LASIK (34 eyes of 24 patients) were enrolled and matched according to preoperative manifest refractive spherical equivalents. The mean preoperative manifest refractive spherical equivalent was -4.69±0.6 and -4.67±0.64 D in the SMILE and LASIK groups, respectively. The safety, efficacy, and predictability were compared 3 months after surgery. Changes in corneal refractive power from the center to peripheral points and their maintenance ratios were analyzed and compared between the two groups.

Results: In the SMILE and LASIK groups, 82.4% and 85.3% of patients, respectively, achieved 20/13 or better uncorrected distance visual acuity (=1.00). There were no eyes that lost two or more lines of corrected distance visual acuity in either group. The maintenance ratios of corneal refractive power changes at the peripheral points in the SMILE group were significantly higher than those in the LASIK group (<0.05).

Conclusion: Both groups achieved similar high efficacy and safety. SMILE surgery resulted in higher refractive power correction in the peripheral cornea than LASIK surgery.
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http://dx.doi.org/10.2147/OPTH.S161883DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5953304PMC
May 2018

[Dihydropyrimidine dehydrogenase deficiency causes severe adverse effects of capecitabine].

Nihon Shokakibyo Gakkai Zasshi 2018;115(3):290-298

Department of Gastroenterology, Shiga University of Medical Science.

We report the case of a 61-year-old man who experienced severe adverse effects of capecitabine because of dihydropyrimidine dehydrogenase (DPD) deficiency. In 2016, he visited our hospital for adenocarcinoma of the gastroesophageal junction and was prescribed neoadjuvant chemotherapy with capecitabine, cisplatin, and trastuzumab. On day 14 of chemotherapy, he developed severe diarrhea, canker sores, enterocolitis, febrile neutropenia, and thrombocytopenia. He was then urgently hospitalized, and anticancer treatment was stopped. We administered antibiotics and G-CSF, and he gradually recovered. However, he complained of severe bloody stools due to hemorrhagic enteritis;hence, we performed a bowel resection. The level of DPD protein, which metabolizes 5-fluorouracil (FU), was very low (2.83U/mg). Therefore, he was diagnosed with DPD deficiency, based on DPD protein or urinary pyrimidine levels, which caused serious adverse effects of capecitabine. It is a rare condition, and 5-FU administration should be avoided in DPD deficiency cases.
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http://dx.doi.org/10.11405/nisshoshi.115.290DOI Listing
June 2019

Refractive Outcomes After Phototherapeutic Refractive Keratectomy for Granular Corneal Dystrophy.

Cornea 2018 May;37(5):548-553

Nagoya Eye Clinic, Nagoya, Japan.

Purpose: This retrospective study aimed to evaluate the effectiveness of a novel procedure named phototherapeutic refractive keratectomy (PTRK), which is a sequential procedure composed of phototherapeutic keratectomy ablation for removal of opacities, followed by smoothing ablation for reducing the corneal surface irregularities and photorefractive keratectomy ablation for correcting refractive errors in eyes with primary granular corneal dystrophy.

Methods: Twenty-three eyes of 17 patients with granular corneal dystrophy were treated with PTRK. Preoperative and postoperative visual acuity, corneal topography, and changes in spherical equivalent and cylindrical refraction were examined and analyzed.

Results: The mean spherical equivalent power changed from -0.11 ± 1.36 diopters (D) to 0.19 ± 0.91 D postoperatively (P = 0.121). The change in the mean spherical equivalent was +0.30 ± 0.99 D. The mean preoperative uncorrected distance visual acuity (logMAR) of 0.40 ± 0.26 significantly improved to 0.075 ± 0.145 at 3 months after PTRK (P < 0.001). The mean preoperative corrected distance visual acuity (logMAR) of 0.18 ± 0.17 significantly improved to -0.02 ± 0.11 at 3 months after PTRK (P < 0.01). The surface regularity index was significantly decreased from 0.93 ± 0.46 preoperatively to 0.60 ± 0.30 postoperatively (P < 0.001).

Conclusions: Our results showed that PTRK could improve corneal surface irregularities and remove opacities. Furthermore, both corrected visual acuity and uncorrected visual acuity improved by the addition of refractive correction. PTRK is a promising surgical procedure for improving postoperative quality of life with a high degree of patient satisfaction.
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http://dx.doi.org/10.1097/ICO.0000000000001548DOI Listing
May 2018

Segmenting Continuous Motions with Hidden Semi-markov Models and Gaussian Processes.

Front Neurorobot 2017 21;11:67. Epub 2017 Dec 21.

Department of Mechanical Engineering and Intelligent Systems, The University of Electro-Communications, Chofu-shi, Japan.

Humans divide perceived continuous information into segments to facilitate recognition. For example, humans can segment speech waves into recognizable morphemes. Analogously, continuous motions are segmented into recognizable unit actions. People can divide continuous information into segments without using explicit segment points. This capacity for unsupervised segmentation is also useful for robots, because it enables them to flexibly learn languages, gestures, and actions. In this paper, we propose a Gaussian process-hidden semi-Markov model (GP-HSMM) that can divide continuous time series data into segments in an unsupervised manner. Our proposed method consists of a generative model based on the hidden semi-Markov model (HSMM), the emission distributions of which are Gaussian processes (GPs). Continuous time series data is generated by connecting segments generated by the GP. Segmentation can be achieved by using forward filtering-backward sampling to estimate the model's parameters, including the lengths and classes of the segments. In an experiment using the CMU motion capture dataset, we tested GP-HSMM with motion capture data containing simple exercise motions; the results of this experiment showed that the proposed GP-HSMM was comparable with other methods. We also conducted an experiment using karate motion capture data, which is more complex than exercise motion capture data; in this experiment, the segmentation accuracy of GP-HSMM was 0.92, which outperformed other methods.
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http://dx.doi.org/10.3389/fnbot.2017.00067DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5742615PMC
December 2017

Implantable Collamer Lens Sizing Method Based on Swept-Source Anterior Segment Optical Coherence Tomography.

Am J Ophthalmol 2018 03 30;187:99-107. Epub 2017 Dec 30.

Nagoya Eye Clinic, Nagoya, Japan.

Purpose: To develop and evaluate the accuracy of a size-determination formula using anterior segment optical coherence tomography (AS-OCT) parameters.

Design: Interventional case series.

Methods: This study included 46 eyes of 23 patients with implantable collamer lens (ICL). Preoperatively, the anterior segment parameters were measured using high-frequency ultrasound biomicroscopy and AS-OCT. Three months postoperatively, the vaults were measured and the optimal ICL size was calculated using a previously published method. Stepwise multiple regression analysis was performed using the optimal ICL size as a dependent variable; the NK-formula was obtained. Thereafter, 35 eyes of 18 patients were implanted with ICL after the size was calculated using the NK-formula. Vaults measured at 3 months postoperatively were used to evaluate the accuracy of the NK-formula.

Results: The distance between scleral spurs (ACW) and crystalline lens rise (CLR) were selected as significant parameters for the regression model (R = 0.68, P < .05). There were 25 (71%), 8 (23%), and 2 (6%) eyes in the moderate, high, and low vault categories, respectively. Using the STAAR nomogram for ICL sizing, 24 eyes (69%) were fitted in the moderate vault. The mean absolute error of the predicted vault was significantly lower with the NK-formula (0.190 ± 0.129 mm) than with the STAAR nomogram (0.331 ± 0.235 mm, P = .002, paired t test).

Conclusion: AS-OCT is useful for ICL size determination, because it calculates the anterior segment parameters using automatic analysis. The NK-formula shows higher accuracy for predicting vault than the STAAR nomogram.
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http://dx.doi.org/10.1016/j.ajo.2017.12.015DOI Listing
March 2018

Comparison of the relationship between multiple parameters of glycemic variability and coronary plaque vulnerability assessed by virtual histology-intravascular ultrasound.

J Diabetes Investig 2017 Sep 16. Epub 2017 Sep 16.

Division of Diabetes and Endocrinology, Kobe University Graduate School of Medicine, Kobe, Japan.

Aims/introduction: Increased glycemic variability is an important contributing factor to coronary artery disease. Although various parameters of glycemic variability can be derived by continuous glucose monitoring, the clinical relevance of individual parameters has remained unclear. We have now analyzed the relationship of such parameters to coronary plaque vulnerability.

Materials And Methods: The standard deviation of glucose levels (SD glucose), mean amplitude of glycemic excursions (MAGE), continuous overlapping net glycemic action calculated every 1 h (CONGA-1) and mean of daily differences (MODD) were calculated from continuous glucose monitoring data for 53 patients hospitalized for percutaneous coronary intervention. The relationship of these parameters to the percentage necrotic core of total plaque volume (%NC) as assessed by virtual histology-intravascular ultrasound (a predictor of coronary plaque rupture) was evaluated.

Results: All parameters of glycemic variability were significantly correlated with %NC, with correlation coefficients of 0.593, 0.626, 0.318, and 0.388 for log(SD glucose), log(MAGE), CONGA-1 and log(MODD), respectively. Simple linear regression analysis showed that the coefficients of determination for %NC and either log(SD glucose; 0.352) or log(MAGE; 0.392) were greater than those for %NC and either CONGA-1 (0.101) or log(MODD; 0.151), whereas the residual sums of squares for the former relationships (1045.1 and 979.5, respectively) were smaller than those for the latter (1449.3 and 1369.6, respectively).

Conclusions: The present data suggest that SD glucose and MAGE are more highly correlated with coronary plaque vulnerability than are CONGA-1 and MODD, and are thus likely better predictors of coronary artery disease.
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http://dx.doi.org/10.1111/jdi.12750DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5934272PMC
September 2017