Single-camera photogrammetry using a mobile phone for low-cost documentation of corpses.

Photogrammetry is a technique for studying and defining objects' shape, dimension, and position in a three-dimensional space using measurements obtained from two-dimensional photographs. It has gained popularity following the development of computer graphics technologies and has been applied to various branches of medicine. In this study, the authors present a method for low-cost photorealistic documentation of corpses during autopsy using single-camera photogrammetry with a mobile phone. Besides representing the body by demonstrating the injured and non-injured body parts as control, evidencing the body parts on a 3D reconstruction allows easy explanation to nonmedical experts such as lawyers.

Comfort Care.

Description Death does not thrill me anymore. I am a trauma surgeon extraordinaire! The patient had suffered a traumatic brain injury and has struggled for weeks. He is only 16. Today, the family decided to make him "comfort care." I was at the end of my call, exhausted, drained of all energy. I looked out of the ICU window and saw the fading rain and the city lights. It somehow reminded me of a precious life ebbing away, and I burst into a silent scream. I am still human.

Enhancing stroke risk and prognostic timeframe assessment with deep learning and a broad range of retinal biomarkers.

Stroke stands as a major global health issue, causing high death and disability rates and significant social and economic burdens. The effectiveness of existing stroke risk assessment methods is questionable due to their use of inconsistent and varying biomarkers, which may lead to unpredictable risk evaluations. This study introduces an automatic deep learning-based system for predicting stroke risk (both ischemic and hemorrhagic) and estimating the time frame of its occurrence, utilizing a comprehensive set of known retinal biomarkers from fundus images. Our system, tested on the UK Biobank and DRSSW datasets, achieved AUROC scores of 0.83 (95% CI: 0.79-0.85) and 0.93 (95% CI: 0.9-0.95), respectively. These results not only highlight our system's advantage over established benchmarks but also underscore the predictive power of retinal biomarkers in assessing stroke risk and the unique effectiveness of each biomarker. Additionally, the correlation between retinal biomarkers and cardiovascular diseases broadens the potential application of our system, making it a versatile tool for predicting a wide range of cardiovascular conditions.

Association of retinal microvascular curve tortuosity and multiple sclerosis: A cross-section analysis from the UK Biobank.

BACKGROUND: There is growing evidence supporting that vascular abnormalities contribute to multiple sclerosis (MS), and retinal microvasculature functions as a visible window to observe vessels. We hypothesized that retinal vascular curve tortuosity is associated with MS, which this study aims to address. METHODS: Participants from the UK Biobank with complete clinical records and gradable fundus photos were included in the study. Arteriolar and venular curve tortuosity and vessel area density are quantified automatically using a deep learning system. Individuals with MS were matched to healthy controls using propensity score matching (PSM). Conditional logistic regression was used to investigate the association between retinal vascular characteristics and MS. We also used a receiver operating characteristic (ROC) curve to assess the diagnostic performance of MS. RESULTS: Venular curve tortuosity (VCT) was found to be significantly associated with MS. And patients with multiple sclerosis were probable to have lower VCT than the non-MS group (OR = 0.22 [95 % CI, 0.05 to 0.92], P < 0.05). CONCLUSIONS: Our study reveals a significant association between vessel curve tortuosity and MS. The lower curve tortuosity of the retinal venular network may indicate a higher risk of incident multiple sclerosis.

Bad beauty: Aesthetic judgments are influenced by references to morally contentious content in photographs.

Affective responses can influence evaluative judgments, but how are subjective beauty ratings affected by references to morally contentious elements in aesthetic stimuli? In an online experiment (N = 460), we investigated the relationship between two types of descriptive texts (Neutral vs. Negative) and the beauty ratings of 25 photographs that depict sources of environmental pollution. For each photograph, the neutral descriptive text contained general information, whereas the negative descriptive text addressed the pollution source. Further, we explored whether this relationship is mediated by changes in positive and negative affect, and how it interacts with the biospheric values of participants. Our results showed that (1) participants in the Negative Condition rated the photographs as less beautiful than in the Neutral Condition, (2) this relationship was partially mediated by changes in negative affect, and (3) in the Negative Condition, participants with higher levels of biospheric values rated the photographs as less beautiful. Our results indicate that individual values, as well as affective responses induced by aesthetic stimuli, directly influence subjective beauty. This aligns with current theoretical frameworks and fills a gap in experimental research. Finally, we discuss limitations and directions for future studies. PSYCHINFO CLASSIFICATION CODE: 2340.

Teledentistry accuracy for caries diagnosis: a systematic review of in-vivo studies using extra-oral photography methods.

BACKGROUND: Dental caries is a global public health concern, and early detection is essential. Traditional methods, particularly visual examination, face access and cost challenges. Teledentistry, as an emerging technology, offers the possibility to overcome such barriers, and it must be given high priority for assessment to optimize the performance of oral healthcare systems. The aim of this study was to systematically review the literature evaluating the diagnostic accuracy of teledentistry using photographs taken by Digital Single Lens Reflex (DSLR) and smartphone cameras against visual clinical examination in either primary or permanent dentition. METHODS: The review followed PRISMA-DTA guidelines, and the PubMed, Scopus, and Embase databases were searched through December 2022. Original in-vivo studies comparing dental caries diagnosis via images taken by DSLR or smartphone cameras with clinical examination were included. The QUADAS-2 was used to assess the risk of bias and concerns regarding applicability. Meta-analysis was not performed due to heterogeneity among the studies. Therefore, the data were analyzed narratively by the research team. RESULTS: In the 19 studies included, the sensitivity and specificity ranged from 48 to 98.3% and from 83 to 100%, respectively. The variability in performance was attributed to factors such as study design and diagnostic criteria. Specific tooth surfaces and lesion stages must be considered when interpreting outcomes. Using smartphones for dental photography was common due to the convenience and accessibility of these devices. The employment of mid-level dental providers for remote screening yielded comparable results to those of dentists. Potential bias in patient selection was indicated, suggesting a need for improvements in study design. CONCLUSION: The diagnostic accuracy of teledentistry for caries detection is comparable to that of traditional clinical examination. The findings establish teledentistry's effectiveness, particularly in lower income settings or areas with access problems. While the results of this review is promising, conducting several more rigorous studies with well-designed methodologies can fully validate the diagnostic accuracy of teledentistry for dental caries to make oral health care provision more efficient and equitable. REGISTRATION: This study was registered with PROSPERO (CRD42023417437).

Deep learning for predicting circular retinal nerve fiber layer thickness from fundus photographs and diagnosing glaucoma.

Purpose: This study aimed to propose a new deep learning (DL) approach to automatically predict the retinal nerve fiber layer thickness (RNFLT) around optic disc regions in fundus photography trained by optical coherence tomography (OCT) and diagnose glaucoma based on the predicted comprehensive information about RNFLT. Methods: A total of 1403 pairs of fundus photographs and OCT RNFLT scans from 1403 eyes of 1196 participants were included. A residual deep neural network was trained to predict the RNFLT for each local image in a fundus photograph, and then a RNFLT report was generated based on the local images. Two indicators were designed based on the generated report. The support vector machines (SVM) algorithm was used to diagnose glaucoma based on the two indicators. Results: A strong correlation was found between the predicted and actual RNFLT values on local images. On three testing datasets, we found the Pearson r to be 0.893, 0.850, and 0.831, respectively, and the mean absolute error of the prediction to be 14.345, 17.780, and 19.250 µm, respectively. The area under the receiver operating characteristic curves for discriminating glaucomatous from healthy eyes was 0.860 (95 % confidence interval, 0.799-0.921). Conclusions: We established a novel local image-based DL approach to provide comprehensive quantitative information on RNFLT in fundus photographs, which was used to diagnose glaucoma. In addition, training a deep neural network based on local images to predict objective detail information in fundus photographs provided a new paradigm for the diagnosis of ophthalmic diseases.

Assessment of Tooth Shade Measurement Precision and Consistency with Digital Photography Calibration System.

Objectives: To ascertain the degree of precision and repeatability inherent in the "capture to edit" digital imaging system, namely the ColorChecker Passport Photo (X-Rite, MI, USA), and to juxtapose its performance against spectrophotometric assessments utilizing the Vita Easyshade® (Vita Zahnfabrik, H Rauter GmbH & Co. KG., Bad Sackingen, Germany) for the same set of teeth. Materials and methods: Eighty participants aged 19-25 were included in the study; all of them were Croatian students at the School of Dental Medicine, University of Zagreb. Color measurements of the maxillary right central incisors were performed in controlled, standardized laboratory conditions. The measurements were performed on calibrated digital photographs by an experienced clinician three times in a row, and L, a, and b of CIELAB color space values were recorded. The same procedure was performed using the Vita Easyshade 5.0 spectrophotometer (Vita Zahnfabrik, Bad Säckingen, Germany) in "Tooth single" mode. Results: The Cronbach's alpha was used as a repeatability measurement, thus revealing high consistency for both methods (α=0.94-1). Correlations were moderate (Pearson r=0.44-0.66 p<0.05). Testing confirmed that digital photography is inaccurate as spectrophotometry (p<0.05). An analysis of errors of means and their standard deviations revealed consistent discrepancies with minor deviations. Conclusion: The "capture to edit" method showed high consistency (Cronbach's α=0.94-0.96), and it exhibits comparability in terms of variability, reliability, and repeatability when compared to spectrophotometric measurement (VitaShade 5, VitaZahnfabrik). Disparities between the methods are evident and anticipated, yet they do not follow a consistently linear pattern. The combination of repeatability and consistency renders the "capture to edit" method a valuable tool for enhanced color mapping, thus facilitating comparisons between digital images.

Posttraumatic Growth and Continued Bonds in Fathers Receiving Bereavement Photography Following Perinatal Loss: A Mixed-Methods Study.

Research exploring fathers' experiences of using bereavement photography after perinatal loss is lacking. Using continuing bonds theory, this study aims to investigate fathers'experiences of bereavement photography and predictors of posttraumatic growth (PTG). Mixed methodology was employed with participants (n = 29). A hierarchical regression showed that there were no significant associations between continuing bonds and PTG, but time since death predicted PTG in bereaved fathers. Further, a t test indicated that there was no significant difference in PTG for mothers and fathers. A thematic analysis was conducted on the qualitative data from an open-ended survey question (n = 23) and semi-structured interviews (n = 3) with fathers. The qualitative analysis of fathers' responses showed themes relating to bonding/connection, capturing memories, recommendations to receive photography help with grieving, validation, memory-making and continuing bonds, and engagement with photos. Fathers valued bereavement photographs as it enabled them to integrate grief over time.

Low-cost, high-volume imaging for entomological digitization.

Large-scale digitization of natural history collections requires automation of image acquisition and processing. Reflecting this fact, various approaches, some highly sophisticated, have been developed to support imaging of museum specimens. However, most of these systems are complex and expensive, restricting their deployment. Here we describe a simple, inexpensive technique for imaging arthropods larger than 5 mm. By mounting a digital SLR camera on a CNC (computer numerical control) motor-drive rig, we created a system that captures high-resolution z-axis stacked images (6960 × 4640 pixels) of 95 specimens in 30 minutes. This system can be assembled inexpensively ($1000 USD without a camera) and it is easy to set-up and maintain. By coupling low cost with high production capacity, it represents a solution for digitizing any natural history collection.

Development of a measuring app for systemic sclerosis-related digital ulceration (SALVE: Scleroderma App for Lesion VErification).

OBJECTIVES: To test the hypothesis that photographs (in addition to self-reported data) can be collected daily by patients with systemic sclerosis (SSc) using a smartphone app designed specifically for digital lesions, and could provide an objective outcome measure for use in clinical trials. METHODS: An app was developed to collect images and patient reported outcome measures (PROMS) including Pain score and the Hand Disability in Systemic Sclerosis-Digital Ulcers (HDISS-DU) questionnaire. Participants photographed their lesion(s) each day for 30 days and uploaded images to a secure repository. Lesions were analysed both manually and automatically, using a machine learning approach. RESULTS: 25 patients with SSc-related digital lesions consented of whom 19 completed the 30-day study, with evaluable data from 27 lesions. Mean (standard deviation [SD]) baseline Pain score was 5.7 (2.4) and HDISS-DU 2.2 (0.9), indicating high lesion and disease-related morbidity. 506 images were used in the analysis (mean number of used images per lesion 18.7, SD 8.3). Mean (SD) manual and automated lesion areas at day 1 were 11.6 (16.0) and 13.9 (16.7) mm2 respectively. Manual area decreased by 0.08mm2 per day (2.4mm2 over 30 days) and automated area by 0.1mm2 (3.0mm2 over 30 days). Average gradients of manual and automated measurements over 30 days correlated strongly (r = 0.81). Manual measurements were on average 40% lower than automated, with wide limits of agreement. CONCLUSION: Even patients with significant hand disability were able to use the app. Automated measurement of finger lesions could be valuable as an outcome measure in clinical trials.

Home / Archives / Vol. 12 No. 1 (2024) / Articles SPATIAL DISTRIBUTION OF MOLAR INCISOR HYPOMINERALIZATION (MIH) OPACITIES IN FIRST PERMANENT MOLARS

Aim: To evaluate the spatial distribution of MIH opacities in first permanent molars (FPM). Materials and methods: an analysis of intraoral photographs of FPM with demarcated MIH opacities was conducted. The presence of opacity was computed in a digital matrix, discriminating the anatomical regions of the FPM surfaces. The frequencies of distribution of the opacities were descriptively analyzed through 227 FPM digital images of 89 children built in GIMP and Python and by Spearman correlation (= 0,05). Results: the occlusal surface was the most affected one (94% to 100%). In the upper FPM, the palatine surface was the second most affected one (84%-91%). In the lower FPM, the vestibular surface was the second most affected one (85%-80%). A similar pattern of opacity distribution was observed in the contralateral teeth. On smooth surfaces, opacities were more frequent in the regions closer to the occlusal surface than to the cervical one. Conclusion: MIH opacities were mostly present on occlusal, vestibular, and lingual/palatine surfaces, respectively. There is a possibility that the occurrences are in accordance with the chronology of dental formation.

Effect of different instrumental techniques and clinical experience on shade matching.

PURPOSE: Many factors can affect the aesthetics of dental restorations, including the instrumental techniques used in shade matching, and can lead to clinical failure. The aim of this study was to investigate the effectiveness of using the cross-polarization digital photograph technique and intraoral scanners for shade matching, and also evaluate the effect of the level of clinical experience on shade matching success. MATERIALS AND METHODS: Color analysis was performed on the maxillary right central incisors of 10 subject models with Vita Easyshade. Intraoral scanning was performed 10 times on each model using TRIOS 3 and color analysis was performed from the same spot. Then cross-polarized and non-polarized photographs of the models were taken with standard settings using a gray reference card. Each shade tab of the Vita System 3D-Master scale was also photographed with two different polarization techniques. Four groups (n = 12), including prosthodontics faculty staff, postgraduate students in prosthodontics, undergraduate students, and dental technicians matched the shade tabs and the model photographs obtained with both techniques on a standardized computer screen. Finally, the color differences between the shade tabs and maxillary central incisors matched by observers from four different groups were recorded using a colorimeter, Classic Color Meter, in accordance with the CIELAB system and CIEDE2000 (ΔE00) values were calculated. The data were compared with the acceptability threshold of 1.80 for ΔE00. The data obtained from the observers were analyzed with IBM SPSS Statistics 26.0 Release Notes program. Independent Samples t-test was used to compare normally distributed data according to binary groups. The level of significance was 0.05. RESULTS: A statistically significant difference was found in the shade matching on photographs taken with different techniques in postgraduate students (p = 0.02). Also, there was a statistically significant difference in success between the groups that made shade matching based on photographs obtained with the non-polarization technique (p = 0.00). The undergraduate students achieved statistically significantly lower results than all other groups (ΔE00 = 5.57 ± 1.07). The kappa value between the intraoral scanner and spectrophotometer results was 0.10, and this value was not statistically significant (p = 0.32). CONCLUSIONS: The cross-polarization technique used especially for shade matching is not superior to the non-polarization technique. Academic and clinical experience might be correlated with shade-matching success with the non-polarization technique. The clinical acceptability threshold could not be achieved in the shade matchings made on digital photographs taken with both techniques. Shade matching performed with an intraoral scanner did not yield reliable results.

Improving diabetic retinopathy screening at the point of care: integrating telemedicine to overcome current challenges.

OBJECTIVE: To investigate the utility of point of care screening of diabetic retinopathy (DR) and the impact of a telemedicine program to overcome current challenges. METHODS: This was a retrospective study on people with type 2 diabetes mellitus (T2DM) who were screened for DR using the single-field non-mydriatic fundus photography at the point of care during routine follow-up visits at endocrinology clinic. Retinal images were uploaded and sent to a retina specialist for review. Reports indicating retinopathy status and the need for direct retinal examination were transmitted back to the endocrinology clinic. All patients were informed about DR status and, if needed, referred to the retina specialist for direct retinal examination. RESULTS: Of the 1159 individuals screened for DR, 417 persons (35.98%) were screen-positive and referred to the retina specialist for direct retinal examination. A total of 121 individuals (29.01%) underwent direct retinal examination by the specialist. Diabetes macular edema (DME) was detected in 12.1%. In addition, non-proliferative diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR) were detected in 53.4% and 2.6% of the patients, respectively. CONCLUSION: Integrating DR screening program at the point of care at the secondary care services improves the rate of DR screening as well as detection of sight threatening retinopathy and provides the opportunity for timely intervention in order to prevent advanced retinopathy in people with T2DM.

Capturing the art and science of dentistry in a lens: Digital dental photography.

Dental photography is now an excellent tool that plays a crucial role in dentistry as it helps in documenting and analyzing the oral conditions of patients. Photography provides a visual representation of the teeth, gums, and other oral structures, which aids in diagnosis, treatment planning, and monitoring the progress of treatment. Therefore, it is essential for dental professionals to understand the importance of dental photography and incorporate photography it into regular practice. The purpose of this paper is to provide emphasis and elucidate the path of dental photography easier for dental student and practitioner.

"You Aren't Alone": An Analysis of Trans Latinas' Use of Instagram.

Social media platforms, such as Instagram, provide space for marginalized groups to connect, learn about and express themselves, and cultivate community. Trans Latinas, a group target of violence and discrimination, resist by expressing themselves and building community through social media. As cisgender researchers, we explored how trans Latinas use #translatina on Instagram as a shared space to present themselves and their identities, to leverage this knowledge in our fields. We analyzed 134 posts in February and March of 2020 employing basic and interpretive content analyses while considering Goffman's theory of presentation of self. Results showed that trans Latinas mostly presented individually through posed selfies taken near the camera, using a straight camera angle, standing, not smiling, and making eye contact. Most users wore makeup, styled hair, and accessories. Analyzing written captions and photos, four themes were constructed to understand how trans Latinas presented their identities and connected with others: (1) expressions of beauty and femininity, (2) fostering community, (3) commercial or work, and (4) feeling good and confident. These results have implications for mental health and health promotion practices, as social media could serve as affirming spaces for trans Latinas to reinforce their self-determination, maintain a sense of self, and build community.

Study on the methods of visualizing bloodstains after thermal exposure.

To establish the correlation between thermal conditions imposed on bloodstains and visualizing effect of enhancement techniques, infrared photography and four chemical enhancement reagents were used to visualize bloodstains following thermal exposure. A black tile was selected as the substrate to intensify the visualization challenge, with a Cone Calorimeter serving as the standardized heating source to control thermal conditions. Compared with standard photography, infrared photography is proven to be a valuable complement to chemical reagents, showing significant advantages in visualizing bloodstains after thermal exposure. However, it is worth noting that infrared image fell short of standard image when bloodstains displayed raised, embossed morphology or when bloodstains almost disappeared under specific conditions. The enhancement effectiveness was found to be strongly correlated with thermal conditions imposed on bloodstains, and the morphology evolution of bloodstains during heating affected the chemical enhancement effect additionally, especially when the bulge morphology was formed, and it was observed that reagents were more effective after removing the dense shell of the bulge. Among the four selected chemical enhancement reagents, fluorescein performed exceptionally well, maintaining its effectiveness even for bloodstains heated at 641°C for 10 min. TMB demonstrated its visualizing ability for bloodstains heated at 396°C for 5 min and heated at 310°C for 20 min. BLUESTAR® followed afterwards, while luminol performed worst. The correlation between thermal conditions imposed on bloodstains and the corresponding visualizing effectiveness of enhancement techniques provides important references for detecting bloodstains at fire scenes.

Comparison of Extended Skin Cancer Screening Using a Three-Step Advanced Imaging Programme vs. Standard-of-Care Examination in a High-Risk Melanoma Patient Cohort.

Modern diagnostic procedures, such as three-dimensional total body photography (3D-TBP), digital dermoscopy (DD), and reflectance confocal microscopy (RCM), can improve melanoma diagnosis, particularly in high-risk patients. This study assessed the benefits of combining these advanced imaging techniques in a three-step programme in managing high-risk patients. This study included 410 high-risk melanoma patients who underwent a specialised imaging consultation in addition to their regular skin examinations in outpatient care. At each visit, the patients underwent a 3D-TBP, a DD for suspicious findings, and an RCM for unclear DD findings. The histological findings of excisions initiated based on imaging consultation and outpatient care were compared. Imaging consultation detected sixteen confirmed melanomas (eight invasive and eight in situ) in 39 excised pigmented lesions. Outpatient care examination detected seven confirmed melanomas (one invasive and six in situ) in 163 excised melanocytic lesions. The number needed to excise (NNE) in the imaging consultation was significantly lower than that in the outpatient care (2.4 vs. 23.3). The NNE was 2.6 for DD and 2.3 for RCM. DD, 3D-TBP, or RCM detected melanomas that were not detected by the other imaging methods. The three-step imaging programme improves melanoma detection and reduces the number of unnecessary excisions in high-risk patients.