Surface-enhanced Raman spectroscopy (SERS) for the characterization of supernatants of bacterial cultures of bacterial strains causing sinusitis.

BACKGROUND: Sinusitis is defined as inflammation of the paranasal sinus mucous membrane lining caused by bacteria which usually invade the sinus by upper respiratory tract viral infections (UTI). OBJECTIVES: In the present study, Surface-enhanced Raman spectroscopy (SERS) has been applied to differentiate and characterize supernatant samples, in triplicate, of three different types of bacteria which are considered leading cause of sinusitis disease. METHODS: For this purpose, supernatant samples of three different strains of bacteria namely Staphylococcus aureus, Klebsiella pneumoniae and Enterococcus faecalis. The SERS has identified significant changes as a result of secretions of biomolecules by these bacteria in their supernatants which can be helpful to explore the potential of this technique for the identification and characterization of different strains of bacteria causing same disease. RESULTS: These differentiating characteristic SERS spectral features including 552 cm-1 (C-S-S-C bonds), 951 cm-1 (CN stretching), 1008 cm-1 (Phenylalanine), 1032 cm-1 (In plane CH bending mode Phenylalanine), 1280 cm-1, 1320 cm-1, 1329 cm-1 (Amide III band), 1368 cm-1, 1400 cm-1, 1420 cm-1 (COO-sym. stretching and CH bending), 1583 cm-1 (Tyrosine) correspond to Proteins and 1051 cm-1 (C-C, C-O, -C-OH def.) correspond to carbohydrates contents of these three different types of bacterial secretions in their respective supernatants. Furthermore, multivariate data analysis techniques like principal component analysis (PCA) and a supervised method partial least squares-discriminant analysis (PLS-DA) were found to be useful for the identification and characterization of different bacterial supernatants. CONCLUSIONS: Surface-enhanced Raman spectroscopy is proven to be a helpful approach for the characterization and discrimination of three bacterial supernatants including S. aureus, K. pneumonia and E. faecalis.

Quality of reporting of randomised controlled trials of artificial intelligence in healthcare: a systematic review.

OBJECTIVES: The aim of this study was to evaluate the quality of reporting of randomised controlled trials (RCTs) of artificial intelligence (AI) in healthcare against Consolidated Standards of Reporting Trials-AI (CONSORT-AI) guidelines. DESIGN: Systematic review. DATA SOURCES: We searched PubMed and EMBASE databases for studies reported from January 2015 to December 2021. ELIGIBILITY CRITERIA: We included RCTs reported in English that used AI as the intervention. Protocols, conference abstracts, studies on robotics and studies related to medical education were excluded. DATA EXTRACTION: The included studies were graded using the CONSORT-AI checklist, comprising 43 items, by two independent graders. The results were tabulated and descriptive statistics were reported. RESULTS: We screened 1501 potential abstracts, of which 112 full-text articles were reviewed for eligibility. A total of 42 studies were included. The number of participants ranged from 22 to 2352. Only two items of the CONSORT-AI items were fully reported in all studies. Five items were not applicable in more than 85% of the studies. Nineteen per cent (8/42) of the studies did not report more than 50% (21/43) of the CONSORT-AI checklist items. CONCLUSIONS: The quality of reporting of RCTs in AI is suboptimal. As reporting is variable in existing RCTs, caution should be exercised in interpreting the findings of some studies.

Choroidal thickness changes following cataract surgery using swept source optical coherence tomography.

OBJECTIVE: The aim of this study was to assess changes in subfoveal choroidal thickness (SFCT), measured using swept-source optical coherence tomography (SS-OCT), after routine phacoemulsification cataract surgery. DESIGN: This is a prospective, interventional, controlled study that took place at Shahzad Eye Hospital, Karachi, Pakistan, between February 2015 and January 2016. PARTICIPANTS: One hundred and one patients who were undergoing routine cataract surgery were recruited. One eye per patient was included. The unoperated fellow eyes acted as controls. METHODS: Swept-source optical coherence tomography scans were performed preoperatively, 1 week postoperatively, and 1 month postoperatively. Two independent graders evaluated the scans to measure the SFCT. The SFCT was measured and recorded for OCT scans from each visit. The general linear model repeated analysis technique was used to assess data from the 3 different time intervals, and paired t tests were used to assess a statistically significant difference between mean preoperative and postoperative SFCT. Probability values of less than 0.05 were considered to be statistically significant. RESULTS: The mean preoperative SFCT in the study eye was 272.9 ± 96.2; SFCT was 278.9 ± 101.4 (p = 0.051) and 281.5 ± 105.2 (p = 0.01) at week 1 and month 1, respectively. In the control eyes, the mean measurement of preoperative SFCT was 274.2 ± 98.5; measurements were 273.8 ± 100.7 (p = 0.875) and 277.9 ± 103.1 (p = 0.063) at week 1 and month 1, respectively. CONCLUSIONS: There was a gradual increase in SFCT at 1 month after cataract removal in the study eyes. The effect was more pronounced in younger individuals and nondiabetic individuals.

Quantifying Microvascular Changes Using OCT Angiography in Diabetic Eyes without Clinical Evidence of Retinopathy.

OBJECTIVE: To compare quantitative OCT angiography (OCTA) parameters of macular ischemia in diabetic eyes without retinopathy with those in healthy nondiabetic controls. DESIGN: Cross-sectional study from August 2014 through June 2017. SUBJECTS: Thirty-nine eyes of 39 diabetic patients without clinical evidence of diabetic retinopathy and 40 eyes of 40 healthy nondiabetic subjects. METHODS: Subjects underwent OCTA imaging using prototype AngioVue software (RTVue XR Avanti). Analyses of the foveal avascular zone (FAZ) and vasculature surrounding the FAZ were performed on the automatically generated en face OCTA images of the superficial and deep retinal vasculatures using vessel-based and FAZ-based metrics. MAIN OUTCOME MEASURES: Comparison of measurements made in the superficial and deep retinal capillary plexuses of diabetic eyes and normal eyes. RESULTS: FAZ-based analysis revealed statistically significant differences between diabetic and normal eyes in FAZ area (superficial and deep layers), perimeter (superficial layer), major axis length (superficial layer), and minor axis layer (superficial and deep layers). Vessel-based analysis revealed statistically significant differences in the binarized flow index (superficial and deep layers), both including and excluding the FAZ area. CONCLUSIONS: Quantitative OCTA parameters reveal subclinical macular ischemia at both the superficial and deep retinal capillary plexuses in diabetic eyes that do not manifest clinical retinopathy. Vessel-based and FAZ-based metrics applied to OCTA images may serve as effective tools for screening and disease monitoring in patients with diabetes without clinical evidence of retinopathy.

Swept-source optical coherence tomography to screen for macular pathology in eyes having routine cataract surgery.

PURPOSE: To determine the incremental benefit of swept-source optical coherence tomography (SS-OCT) in identifying occult macular disease preoperatively in patients scheduled for routine cataract surgery. SETTING: Shahzad Eye Hospital, Karachi, Pakistan. DESIGN: Prospective case series. METHODS: Preoperative SS-OCT scans were performed in all patients scheduled to have cataract surgery between January and March 2016. Scans were subsequently reviewed for the presence of macular abnormalities. Patients with clinically detectable retinal pathologies were excluded. RESULTS: Of the 179 eligible patients, 155 were included in the study. Macular pathology was noted in 17 patients (10.9%). The most commonly identified conditions were age-related macular degeneration (n = 5), idiopathic epiretinal membrane (n = 4), and vitreomacular interface abnormalities (n = 4). Other abnormalities included cystoid macular edema (n = 2) and ellipsoid zone abnormalities (n = 2). Media opacities precluded interpretation of 9 scans (4.7%). CONCLUSIONS: Swept-source OCT was an effective noninvasive modality for detecting macular structural abnormalities, especially in the presence media opacities. Optical coherence tomography imaging should be considered as an adjunct to routine dilated fundus examination for macular evaluation, particularly if premium intraocular lenses are being considered.

Choroidal neovascularization secondary to Best vitelliform macular dystrophy detected by optical coherence tomography angiography.

Best vitelliform macular dystrophy (VMD) is a hereditary condition that causes childhood-onset macular dystrophy. In rare cases, VMD is accompanied by formation of a choroidal neovascular membrane (CNVM). We report a case of CNVM secondary to Best VMD in a 10-year-old boy that was detected using optical coherence tomography angiography, a new noninvasive diagnostic modality that detects motion contrast in repeated B-scans to identify blood flow within vessels.

Comparison of choroidal thickness measurements between spectral-domain OCT and swept-source OCT in normal and diseased eyes.

PURPOSE: Sub-foveal choroidal thickness (SFCT) is affected in many ocular diseases. The aim of this study was to compare SFCT measurements between Topcon 3D 2000 spectral-domain optical coherence tomography (SD-OCT) and Topcon swept-source OCT (SS-OCT), with different laser wavelengths, in normal and diseased populations. MATERIALS AND METHODS: This was a prospective, cross-sectional, noninterventional study including 27 normal volunteers and 27 participants with retinal disease. OCT scans were performed sequentially and under standardized conditions using both SD-OCT and SS-OCT. The OCT scans were evaluated by two independent graders. Paired t-tests and intraclass correlation coefficients (ICCs) were used to assess the statistically significant difference between SFCT measurements as measured by the two devices. RESULTS: Mean SFCT measurements for all 54 participants were 264.9±103.1 µm using SD-OCT (range: 47-470 µm) and 278.5±110.5 µm using SS-OCT (range: 56-502 µm), with an inter-device ICC of 0.850. Greater variability was noted in the diseased eyes. Inter-device ICCs were 0.870 (95% CI; 0.760-0.924) and 0.840 (95% CI; 0.654-0.930) for normal and diseased eyes, respectively. However, the difference was not statistically significant (P=0.132). CONCLUSION: Both machines reliably measure SFCT. Larger studies are needed to confirm these findings.