scholarly journals Anterior-Segment Swept-Source Ocular Coherence Tomography and Scheimpflug Imaging Agreement for Keratometry and Pupil Measurements in Healthy Eyes

2021 ◽  
Vol 10 (24) ◽  
pp. 5789
Author(s):  
Francisco Pérez-Bartolomé ◽  
Carlos Rocha-De-Lossada ◽  
José-María Sánchez-González ◽  
Silvia Feu-Basilio ◽  
Josep Torras-Sanvicens ◽  
...  
Keyword(s):  
Pupil Diameter ◽  
Anterior Segment ◽  
Swept Source ◽  
Ocular Coherence Tomography ◽  
Scheimpflug Imaging ◽  
Angle Kappa ◽  
Student’S T ◽  
Thickness Measurements ◽  
Healthy Eyes ◽  
Student’S T Test

This study examines agreement between the devices Anterion® and Pentacam HR® used for corneal and pupil measurements in healthy eyes. The parameters compared between the two devices were: anterior Km (D), anterior K2 (D), anterior K1 (D), anterior K1 axis (°), anterior astigmatism (D), anterior K max (D), posterior Km (D), posterior K2 (D), posterior K1 (D), posterior K1 axis (°), posterior astigmatism (D), CCT (µm), thinnest point thickness (µm), thinnest point X-coordinate (mm), thinnest point Y-coordinate (mm), pupil diameter (mm), pupil center-corneal vertex distance (mm) (angle kappa), pupil centroid angle (°), pupil centroid X-coordinate (mm), and pupil centroid Y-coordinate (mm). The Student’s t test for independent samples identified significant differences (p < 0.005) between devices for the measurements anterior and posterior flat K axis, posterior flat K, steep K, and mean K. For these last three measurements, although significant, none of the differences were clinically relevant. Corneal power and thickness measurements except Kf axis showed excellent agreement between Anterion and Pentacam. In a clinical setting we would not recommend the interchangeable use of Pentacam and Anterion for measurement of pupil parameters.

Multimodal imaging of pigmented paravenous retinochoroidal atrophy

2020 ◽  
pp. 112067212096548
Author(s):  
Ratnesh Ranjan ◽  
Arvind Jain M ◽  
Shishir Verghese ◽  
George J Manayath ◽  
Venkatapathy Narendran
Keyword(s):  
Multimodal Imaging ◽  
Early Stage ◽  
Anterior Segment ◽  
Fundus Examination ◽  
Swept Source ◽  
Ocular Coherence Tomography ◽  
Corrected Visual Acuity ◽  
Pigmented Paravenous Retinochoroidal Atrophy ◽  
Best Corrected Visual Acuity ◽  
Ocular Coherence Tomography Angiography

Aim: To describe the multimodal imaging findings of pigmented paravenous retinochoroidal atrophy. Methods: A 23-year-old female presented to us for a routine ocular examination. She had a best-corrected visual acuity of 6/6 in both eyes. Anterior segment examination was unremarkable. Fundus examination showed pigmentary changes along the retinal vasculature extending from mid periphery to post-equatorial retina suggesting a diagnosis of pigmented paravenous retinochoroidal atrophy. Swept-source optical coherence tomography of the macula showed choriocapillaris thinning at the mid periphery whereas coherence tomography angiography at the mid periphery showed a relatively normal choriocapillaris vasculature in the early stage of the disease. Conclusion: A relatively normal choriocapillaris structure was seen on ocular coherence tomography angiography which could have been due to a milder form of the disease in a young patient.

scholarly journals Iris Morphological Features in Patients with 360° Angle-Closure Neovascular Glaucoma: An Anterior Segment Optical Coherence Tomography Study

2018 ◽  
Vol 9 (3) ◽  
pp. 449-456 ◽  
Author(s):  
Yui Kobayashi ◽  
Shunsuke Nakakura ◽  
Etsuko Terao ◽  
Yuki Fujio ◽  
Kanae Matsuya ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Trabecular Meshwork ◽  
Pupil Diameter ◽  
Anterior Segment ◽  
Neovascular Glaucoma ◽  
Morphological Features ◽  
Angle Closure ◽  
Control Group ◽  
Optical Coherence ◽  
Swept Source

Purpose: To investigate iris morphological features in 360° angle-closure neovascular glaucoma (NVG) by swept-source anterior segment optical coherence tomography (ASOCT). Patients and Methods: In this retrospective, clinic-based, comparative study, 14 patients with 360° angle-closure NVG and 14 healthy age-matched control subjects were enrolled. All patients enrolled had no prior glaucoma surgery but underwent cataract surgery with intraocular lens implantation. Horizontal scanning images of swept-source ASOCT were analyzed using software calipers in temporal and nasal angle areas. The iris thickness at 1 and 2 mm from the pupil edge, iris length, trabecular meshwork length, peripheral anterior synechia (PAS) length, PAS height ratio (PAS length/trabecular meshwork length), and pupil diameter were measured. Results: Between the groups, there were no statistically significant differences in iris length, trabecular meshwork length, and pupil diameter (p > 0.05). However, the iris thickness was significantly reduced in the NVG group compared with the control group in the temporal and nasal areas (0.306 vs. 0.563 mm/0.326 vs. 0.645 mm at 1 mm, 0.278 vs. 0.523 mm/0.282 vs. 0.546 mm at 2 mm, respectively) (mean, all p < 0.001). In the NVG group, PAS height ratios were 1.55 ± 0.45 (mean ± standard deviation) (range, 0.58–2.30) and 1.55 ± 0.78 (range, 0.68–3.68) at the temporal and nasal angles, respectively. Conclusions: In patients with 360° angle-closure NVG, the iris thickness decreased to about 50% of that in healthy subjects, and the PAS length exceeded the trabecular meshwork length by about 1.5 times.

Serosal and cutaneous recordings of gastric myoelectrical activity in patients with gastroparesis

1994 ◽  
Vol 266 (1) ◽  
pp. G90-G98 ◽  
Author(s):  
J. D. Chen ◽  
B. D. Schirmer ◽  
R. W. McCallum
Keyword(s):  
Electrical Stimulation ◽  
Slow Wave ◽  
Test Meal ◽  
Frequency Change ◽  
Fasting State ◽  
Gastric Myoelectrical Activity ◽  
Myoelectrical Activity ◽  
Gastric Slow Wave ◽  
Student’S T ◽  
Student’S T Test

The aims of this study were to 1) investigate gastric myoelectrical activity in patients with gastroparesis, 2) validate the cutaneous electrogastrogram (EGG) in tracking the frequency change of the gastric slow wave, and 3) investigate the effect of electrical stimulation on gastric myoelectrical activity. Gastric myoelectrical activity was recorded in 12 patients with documented gastroparesis using serosal electrodes for > 200 min in each subject. All recordings were made at least 4 days after surgery. Each session consisted of a 30-min recording in the fasting state and a 30-min recording after a test meal. The test meal (liquid or mixed) was selected according to patient's tolerance. Electrical stimulation was performed in three subjects via the serosal electrodes at a frequency of 3 cycles/min. Gastric myoelectrical activity was recorded using serosal electrodes in each session. The serosal recording showed slow waves of 2.5 to 4.0 cycles/min in all 12 subjects. Absence of spikes was noted in 11 of the 12 subjects. The simultaneous serosal and cutaneous recording of gastric myoelectrical activity showed that the frequency of the EGG was exactly the same as that of the serosal recording. Liquid meals resulted in a significant decrease in slow-wave frequency (Student's t test, P = 0.006), and the EGG accurately reflected this change. Electrical stimulation had no effect on the frequency of the gastric slow wave and did not induce spikes.(ABSTRACT TRUNCATED AT 250 WORDS)

The Effect of Changes in Dialysate Volume on Glucose and Urea Equilibration

1994 ◽  
Vol 14 (3) ◽  
pp. 236-239 ◽  
Author(s):  
Edward C. Kohaut ◽  
F. Bryson Waldo ◽  
Mark R. Benfield
Keyword(s):  
Renal Failure ◽  
Chronic Renal Failure ◽  
Prospective Study ◽  
Body Surface ◽  
Patient Population ◽  
Different Ages ◽  
Student’S T ◽  
A Prospective Study ◽  
Dialysate Volume ◽  
Student’S T Test

Objectives To determine the effect of changing dialysate volume on urea and glucoseequilibration curves and to determine, if dialysate volume is prescribed on the basis of body surface area, whether equilibration curves will be consistent in patients of different sizes and ages. Design A prospective study wherein children with acute or chronic renal failure had peritoneal equilibration studies done with dwell volumes of 30 mL/kg, 40 mL/kg, and 1200 mL/m2. Patient Population Twenty-two children: 7 under 3 years of age; 8 between 3 and 10 years of age; 7 older than 10 years of age. Statistics Student's t-test. Results Urea and glucose equilibrated rapidly at dwell volumes of 30 mL/kg, slower at dwell volumes of 40 mL/kg, and slowest at dwell volumes of 1200 mL/m2. Equilibration curves were similar in children of different ages when dialysate volumes of 1200 mL/m2 were infused. Conclusion Dialysate volumes of 1200 mL/m2 should be used when equilibration studies are being done to compare individuals of different ages and sizes.

scholarly journals Influence of rebubbling on anterior segment parameters and refractive outcomes in eyes with DMEK for Fuchs endothelial dystrophy

2021 ◽  
Author(s):  
Bishr Agha ◽  
Raimund Forster ◽  
Thomas Kohnen ◽  
Ingo Schmack
Keyword(s):  
Visual Acuity ◽  
Endothelial Cell ◽  
Anterior Segment ◽  
Cell Loss ◽  
Endothelial Cell Loss ◽  
Refractive Outcome ◽  
Refractive Outcomes ◽  
Scheimpflug Imaging ◽  
Fuchs Endothelial Dystrophy ◽  
Anterior Segment Parameters

Abstract Purpose To evaluate the potential impact of rebubbling on the anterior segment parameters and refractive outcomes in patients with graft detachment following uneventful DMEK for Fuchs endothelial dystrophy (FED). Methods Retrospective institutional cohort study of comparing 34 eyes of 31 patients with rebubbling for graft detachment following Descemet membrane endothelial keratoplasty (DMEK) to 33 eyes of 28 patients with uneventful DMEK. Main outcome parameters were various corneal parameters obtained by Scheimpflug imaging, refractive outcome, corrected distance visual acuity (CDVA), and endothelial cell density (ECD). Results Anterior and posterior corneal astigmatism, corneal densitometry, central corneal thickness, and anterior chamber depth and volume showed no significant differences. Preoperative distribution of astigmatism axis orientations showed a high proportion of anterior corneal with-the-rule astigmatism (71%) in eyes requiring rebubbling. Mean postoperative cylinder in the rebubbling group (1.21 ± 0.85 D) was significantly higher compared to the controls (p = 0.04), while differences in spherical equivalent (SE) were insignificant (p = 0.24). Postoperative CDVA was 0.11 ± 0.11 in the control group compared to 0.21 ± 0.17 in the rebubbling group (p = 0.03). Eyes with subsequent rebubbling demonstrated a significantly higher endothelial cell loss (56% versus 37%) (p < 0.001). Conclusion Apart from higher cylinder values, refractive outcome and corneal parameters assessed by Scheimpflug imaging were comparable in eyes with rebubbling and controls. However, a reduced visual acuity and an increased endothelial cell loss should be taken into consideration prior to rebubbling especially in eyes with circumscribed graft detachment.

scholarly journals Development and Validation of 2-Azaspiro [4,5] Decan-3-One (Impurity A) in Gabapentin Determination Method Using qNMR Spectroscopy

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1656
Author(s):  
Nataliya E. Kuz’mina ◽  
Sergey V. Moiseev ◽  
Mikhail D. Khorolskiy ◽  
Anna I. Lutceva
Keyword(s):  
Test Procedure ◽  
Active Pharmaceutical Ingredient ◽  
Test Methods ◽  
Intermediate Precision ◽  
Coefficients Of Variation ◽  
Validation Parameters ◽  
Limit Of Quantitation ◽  
Student’S T ◽  
Development And Validation ◽  
Student’S T Test

The authors developed a 1H qNMR test procedure for identification and quantification of impurity A present in gabapentin active pharmaceutical ingredient (API) and gabapentin products. The validation studies helped to determine the limit of quantitation and assess linearity, accuracy, repeatability, intermediate precision, specificity, and robustness of the procedure. Spike-and-recovery assays were used to calculate standard deviations, coefficients of variation, confidence intervals, bias, Fisher’s F test, and Student’s t-test for assay results. The obtained statistical values satisfy the acceptance criteria for the validation parameters. The authors compared the results of impurity A quantification in gabapentin APIs and capsules by using the 1H qNMR and HPLC test methods.

scholarly journals Descemet membrane suturing to manage recurrent graft detachment in a patient with Descemet membrane endothelial keratoplasty on failed penetrating keratoplasty

2021 ◽  
Vol 13 ◽  
pp. 251584142110277
Author(s):  
Zahra Ashena ◽  
Thomas Hickman-Casey ◽  
Mayank A. Nanavaty
Keyword(s):  
Visual Acuity ◽  
Penetrating Keratoplasty ◽  
Anterior Segment ◽  
Endothelial Keratoplasty ◽  
Descemet Membrane Endothelial Keratoplasty ◽  
Descemet Membrane ◽  
Ocular Coherence Tomography ◽  
Corrected Visual Acuity ◽  
Intracameral Injection ◽  
History Of

A 65-year-old patient with history of keratoconus, mild cataract and penetrating keratoplasty over 30 years ago developed corneal oedema subsequent of graft failure with best corrected visual acuity (BCVA) of counting fingers. He underwent a successful cataract surgery combined with a 7.25 mm Descemet’s Membrane Endothelial Keratoplasty (DMEK) with Sodium Hexafluoride (SF6) gas. His cornea remained oedematous inferiorly at 4 weeks, despite two subsequent re-bubbling due to persistent DMEK detachment inferiorly. This was managed by three radial full thickness 10-0 nylon sutures placed in the inferior cornea along with intracameral injection of air. Following this, his anterior segment ocular coherence tomography (OCT) confirmed complete attachment of the graft, and the sutures were removed 4 weeks later. Unaided visual acuity was 20/63 and BCVA was 20/32 after 8 months. DMEK suturing can be helpful in persistent DMEK detachments, which is refractory to repeated re-bubbling due to uneven posterior surface of previous PK.

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