Artificial intelligence for predictive biomarker discovery in immuno-oncology: a systematic review.

BACKGROUND: The widespread use of immune checkpoint inhibitors (ICIs) has revolutionised treatment of multiple cancer types. However, selecting patients who may benefit from ICI remains challenging. Artificial intelligence (AI) approaches allow exploitation of high-dimension oncological data in research and development of precision immuno-oncology. MATERIALS AND METHODS: We conducted a systematic literature review of peer-reviewed original articles studying the ICI efficacy prediction in cancer patients across five data modalities: genomics (including genomics, transcriptomics, and epigenomics), radiomics, digital pathology (pathomics), and real-world and multimodality data. RESULTS: A total of 90 studies were included in this systematic review, with 80% published in 2021-2022. Among them, 37 studies included genomic, 20 radiomic, 8 pathomic, 20 real-world, and 5 multimodal data. Standard machine learning (ML) methods were used in 72% of studies, deep learning (DL) methods in 22%, and both in 6%. The most frequently studied cancer type was non-small-cell lung cancer (36%), followed by melanoma (16%), while 25% included pan-cancer studies. No prospective study design incorporated AI-based methodologies from the outset; rather, all implemented AI as a post hoc analysis. Novel biomarkers for ICI in radiomics and pathomics were identified using AI approaches, and molecular biomarkers have expanded past genomics into transcriptomics and epigenomics. Finally, complex algorithms and new types of AI-based markers, such as meta-biomarkers, are emerging by integrating multimodal/multi-omics data. CONCLUSION: AI-based methods have expanded the horizon for biomarker discovery, demonstrating the power of integrating multimodal data from existing datasets to discover new meta-biomarkers. While most of the included studies showed promise for AI-based prediction of benefit from immunotherapy, none provided high-level evidence for immediate practice change. A priori planned prospective trial designs are needed to cover all lifecycle steps of these software biomarkers, from development and validation to integration into clinical practice.

Development of a mapping function ("crosswalk") for the conversion of scores between the Oswestry Disability Index (ODI) and the Core Outcome Measures Index (COMI).

INTRODUCTION: The Oswestry Disability Index (ODI) and the Core Outcome Measures Index (COMI) are two commonly used self-rating outcome instruments in patients with lumbar spinal disorders. No formal crosswalk between them exists that would otherwise allow the scores of one to be interpreted in terms of the other. We aimed to create such a mapping function. METHODS: We performed a secondary analysis of ODI and COMI data previously collected from 3324 patients (57 ± 17y; 60.3% female) at baseline and 1y after surgical or conservative treatment. Correlations between scores and Cohen's kappa for agreement (κ) regarding achievement of the minimal clinically important change (MCIC) score on each instrument (ODI, 12.8 points; COMI, 2.2 points) were calculated, and regression models were built. The latter were tested for accuracy in an independent set of registry data from 634 patients (60 ± 15y; 56.8% female). RESULTS: All pairs of measures were significantly positively correlated (baseline, 0.73; 1y follow-up (FU), 0.84; change-scores, 0.73). MCIC for COMI was achieved in 53.9% patients and for ODI, in 52.4%, with 78% agreement on an individual basis (κ = 0.56). Standard errors for the regression slopes and intercepts were low, indicating excellent prediction at the group level, but root mean square residuals (reflecting individual error) were relatively high. ODI was predicted as COMI × 7.13-4.20 (at baseline), COMI × 6.34 + 2.67 (at FU) and COMI × 5.18 + 1.92 (for change-score); COMI was predicted as ODI × 0.075 + 3.64 (baseline), ODI × 0.113 + 0.96 (FU), and ODI × 0.102 + 1.10 (change-score). ICCs were 0.63-0.87 for derived versus actual scores. CONCLUSION: Predictions at the group level were very good and met standards justifying the pooling of data. However, we caution against using individual values for treatment decisions, e.g. attempting to monitor patients over time, first with one instrument and then with the other, due to the lower statistical precision at the individual level. The ability to convert scores via the developed mapping function should open up more centres/registries for collaboration and facilitate the combining of data in meta-analyses.

Precision of the GE Lunar Total Body-Less Head Scan for the Measurement of Three-Compartment Body Composition in Athletes.

INTRODUCTION: Dual energy X-ray absorptiometry (DXA) is widely used for the assessment of lean mass (LM), fat mass (FM) and bone mineral content (BMC). When observing standardised protocols, DXA has a high level of precision for the assessment of total body composition, including the head region. However, including the head region may have limited relevance in athletes and can be problematic when positioning taller athletes who exceed scan boundaries. This study investigated the precision of a new total-body-less-head (TBLH) DXA scan for three-compartment body composition measurement in athletes, with outcomes compared to the standard total-body DXA scan. METHODS: Precision errors were calculated from two consecutive scans with re-positioning (Lunar iDXA, GE Healthcare, Madison, WI), in male and female athletes from a range of sports. TBLH precision was determined from repeat scans in 95 athletes (male n = 55; female n = 40; age: 26.0 ± 8.5 y; body mass: 81.2 ± 20.5 kg; stature: 1.77 ± 0.11 m), and standard total-body scan precision was derived from a sub-sample of 58 athletes (male n = 19; female n = 39; age: 27.6 ± 9.9 y; body mass: 69.6 ± 14.8 kg; stature: 1.72 ± 0.94 m). Data from the sub-sample were also used to compare precision error and 3-compartment body composition outcomes between the standard total-body scan and the TBLH scan. RESULTS: TBLH precision errors [root mean squared-standard deviation, RMS-SD (coefficient of variation, %CV)] were bone mineral content (BMC): 15.6 g (0.5%), lean mass (LM): 254.3 g (0.4%) and fat mass (FM): 199.4 g (1.3%). These outcomes compared favourably to the precision errors derived from the standard total-body scan [BMC: 12.4 g (0.4%), LM: 202.2 g (0.4%), and FM: 160.8 g (1.1%)]. The TBLH scan resulted in lower BMC (-19.5%), LM (-6.6%), and FM (-4.5%) compared to the total-body scan (BMC: 2,308 vs. 2,865 g; LM: 46,954 vs. 50,276 g; FM: 15,183 vs. 15,888 g, all p<0.005). ConclusionThe TBLH scan demonstrates high in-vivo precision comparable to that of the standard total-body scan in a heterogeneous cohort of athletes. Given the impact of head exclusion on total body composition outcomes, TBLH scans should not be used interchangeably with the standard total-body scan.

A quality improvement apprenticeship: Gross anatomy in the time of Covid-19.

The study of anatomy is a team-driven field in which anatomy instruction occurs in small groups in the laboratory with one faculty member guiding students through each anatomical region. One laboratory experience may include several small group instructors in one simultaneous learning session. In comparison, the education of future gross anatomists often happens in an apprenticeship model, where the optimal learning outcomes are met through training with an experienced mentor. It was the vision of the authors to further their education through initiating an inter-institutional exchange to apprentice with innovative mentors in order to bring new ideas back to their own gross anatomy courses. The Southeastern Conference, a consortium of the Universities in the Southern region of the United States often associated with intercollegiate sports, has a host of academic initiatives in addition to the athletic emphasis. The Southeastern Conference Faculty Travel Program is one mechanism by which the organization promotes scholarly excellence. In this case, the Faculty Travel Program provided a way for authors from the University of Kentucky to visit a nearby institution, Vanderbilt University, and learn from like-minded anatomy educators, with the goal of incorporating changes in their courses geared toward quality improvement. After this implementation, positive themes emerged in the student feedback on course evaluations. However, the collaboration was interrupted by the onset of the Covid-19 pandemic. This article examines the strengths of interinstitutional apprenticeship and the benefits of such practices in a time of accelerated change in anatomical instruction.

Topical Review: Perceptual-cognitive Skills, Methods, and Skill-based Comparisons in Interceptive Sports.

SIGNIFICANCE: We give a comprehensive picture of perceptual-cognitive (PC) skills that could contribute to performance in interceptive sports. Both visual skills that are low level and unlikely influenced by experience and higher-level cognitive-attentional skills are considered, informing practitioners for identification and training and alerting researchers to gaps in the literature.Perceptual-cognitive skills and abilities are keys to success in interceptive sports. The interest in identifying which skills and abilities underpin success and hence should be selected and developed is likely going to grow as technologies for skill testing and training continue to advance. Many different methods and measures have been applied to the study of PC skills in the research laboratory and in the field, and research findings across studies have often been inconsistent. In this article, we provide definitional clarity regarding whether a skill is primarily visual attentional (ranging from fundamental/low-level skills to high-level skills) or cognitive. We review those skills that have been studied using sport-specific stimuli or tests, such as postural cue anticipation in baseball, as well as those that are mostly devoid of sport context, considered general skills, such as dynamic visual acuity. In addition to detailing the PC skills and associated methods, we provide an accompanying table of published research since 1995, highlighting studies (for various skills and sports) that have and have not differentiated across skill groups.

Does geographic variation in thermal tolerance in Daphnia represent trade-offs or conditional neutrality?

Geographic variation in thermal tolerance in Daphnia seems to represent genetic load at the loci specifically responsible for heat tolerance resulting from conditional neutrality. We see no evidence of trade-offs between fitness-related traits at 25 °C vs. 10 °C or between two algal diets across Daphnia magna clones from a variety of locations representing the opposite ends of the distribution of long-term heat tolerance. Likewise, we found no evidence of within-environment trade-offs between heat tolerance and fitness-related traits in any of the environments. Neither short-term and long-term heat tolerance shows any consistent relationship with lipid fluorescence polarization and lipid peroxidation across clones or environments. Pervasive positive correlations between fitness-related traits indicate differences in genetic load rather than trade-off based local adaptation or thermal specialization. For heat tolerance such differences may be caused by either relaxation of stabilizing selection due to lower exposure to high temperature extremes, i.e., conditional neutrality, or by small effective population size followed by the recent range expansion.

Breaking free from thermodynamic constraints: thermal acclimation and metabolic compensation in a freshwater zooplankton species.

Respiration rates of ectothermic organisms are affected by environmental temperatures, and sustainable metabolism at high temperatures sometimes limits heat tolerance. Organisms are hypothesized to exhibit acclimatory metabolic compensation effects, decelerating their metabolic processes below Arrhenius expectations based on temperature alone. We tested the hypothesis that either heritable or plastic heat tolerance differences can be explained by metabolic compensation in the eurythermal freshwater zooplankton crustacean Daphnia magna We measured respiration rates in a ramp-up experiment over a range of assay temperatures (5-37°C) in eight genotypes of D. magna representing a range of previously reported acute heat tolerances and, at a narrower range of temperatures (10-35°C), in D. magna with different acclimation history (either 10 or 25°C). We discovered no difference in temperature-specific respiration rates between heat-tolerant and heat-sensitive genotypes. In contrast, we observed acclimation-specific compensatory differences in respiration rates at both extremes of the temperature range studied. Notably, there was a deceleration of oxygen consumption at higher temperature in 25°C-acclimated D. magna relative to their 10°C-acclimated counterparts, observed in active animals, a pattern corroborated by similar changes in filtering rate and, partly, by changes in mitochondrial membrane potential. A recovery experiment indicated that the reduction of respiration was not caused by irreversible damage during exposure to a sublethal temperature. Response time necessary to acquire the respiratory adjustment to high temperature was lower than for low temperature, indicating that metabolic compensation at lower temperatures requires slower, possibly structural changes.

Radio-frequency optomechanical characterization of a silicon nitride drum.

On-chip actuation and readout of mechanical motion is key to characterize mechanical resonators and exploit them for new applications. We capacitively couple a silicon nitride membrane to an off resonant radio-frequency cavity formed by a lumped element circuit. Despite a low cavity quality factor (QE ≈ 7.4) and off resonant, room temperature operation, we are able to parametrize several mechanical modes and estimate their optomechanical coupling strengths. This enables real-time measurements of the membrane's driven motion and fast characterization without requiring a superconducting cavity, thereby eliminating the need for cryogenic cooling. Finally, we observe optomechanically induced transparency and absorption, crucial for a number of applications including sensitive metrology, ground state cooling of mechanical motion and slowing of light.

Integrating Specialty-Specific Clinical Anatomy Education into the Post-Clerkship Curriculum.

Anatomy is a foundational science mainstay of undergraduate medical school education, particularly in the pre-clerkship curriculum. During the post-clerkship curriculum, students closer to graduate medical education may benefit from a focused concentration on human anatomy related to their specific clinical interests. Here, we describe a course for post-clerkship students that uniquely incorporates a multimodal approach of dissection, didactics, and clinical correlation to radiologic imaging, with the opportunity to personalize student learning on a specialty-specific anatomic region. The course increased students' confidence of anatomical knowledge and its clinical relevance. Other institutions may benefit from establishing a similar multimodal integrated post-clerkship anatomy curriculum.

Organizational uptake of NICE guidance in promoting employees' psychological health.

BACKGROUND: Annual costs to organizations of poor mental health are estimated to be between £33 billion and £42 billion. The UK's National Institute for Clinical Excellence (NICE) has produced evidence-based guidance on improving employees' psychological health, designed to encourage organizations to take preventative steps in tackling this high toll. However, the extent of implementation is not known outside the National Health Service. AIMS: To assess the awareness and implementation of NICE guidance on workplace psychological health. METHODS: A total of 163 organizations participated in a survey of UK-based private, public and third sector organizations employing an accumulated minimum of 322 033 workers. RESULTS: Seventy-seven per cent of organizations were aware of the NICE guidance for improving mental well-being in the workplace, but only 37% were familiar with its recommendations. Less than half were aware of systems in place for monitoring employees' mental well-being and only 12% confirmed that this NICE guidance had been implemented in their workplace. Where employee health and well-being featured as a regular board agenda item, awareness and implementation of NICE guidance were more likely. Significant associations were found between organizational sector and size and uptake of many specific features of NICE guidance. CONCLUSIONS: The majority of organizations are aware of NICE guidance in general, but there is a wide gap between this and possession of detailed knowledge and implementation. The role of sector and size of organization is relevant to uptake of some features of NICE guidance, although organizational leadership is important where raised awareness and implementation are concerned.

Children's home and school neighbourhood exposure to alcohol marketing: Using wearable camera and GPS data to directly examine the link between retailer availability and visual exposure to marketing.

BACKGROUND AND AIM: Neighbourhood alcohol availability has been associated with alcohol consumption by children, despite children rarely acquiring alcohol from retailers. This study explores one potential reason for this finding, by evaluating the relationships between neighbourhood alcohol availability and children's actual exposure to alcohol marketing. METHOD: Wearable cameras and GPS devices were worn by 167 children (aged 11-13 y) over a four-day period. Image and GPS data were linked and compared to known alcohol availability data. RESULTS: Off-licence retailer availability and ethnicity were positively associated with children's exposure to marketing in both residential and school neighbourhoods. CONCLUSION: Neighbourhood off-licence alcohol retailers are associated with increased childhood exposure to alcohol marketing.

Empowering Lay-Counsellors with Technology: Masivukeni, a Standardized Multimedia Counselling Support Tool to Deliver ART Counselling.

Lay-counsellors in resource-limited settings convey critical HIV- and ART-information, and face challenges including limited training and variable application of counselling. This study explored lay-counsellors and Department of Health (DoH) perspectives on the utility of a multimedia adherence counselling program. Masivukeni, an mHealth application that provides scaffolding for delivering standardized ART counselling was used in a 3-year randomized control trail at two primary health care clinics in Cape Town, South Africa. In this programmatic and descriptive narrative report, we describe the application; lay-counsellors' response to open-ended questions regarding their experience with using Masivukeni; and perspectives of the City of Cape Town and Western Cape Government DoH, obtained through ongoing engagements and feedback sessions. Counsellors reported Masivukeni empowered them to provide high quality counselling. DoH indicated strong support for a future implementation study assessing feasibility for larger scale roll-out. Masivukeni has potential as a counselling tool in resource-limited settings.

Children sustain high levels of skin DNA photodamage, with a modest increase of serum 25-hydroxyvitamin D3 , after a summer holiday in Northern Europe.

BACKGROUND: Childhood solar ultraviolet radiation (UVR) exposure increases the risk of skin cancer in adulthood, which is associated with mutations caused by UVR-induced cyclobutane pyrimidine dimers (CPD). Solar UVR is also the main source of vitamin D, essential for healthy bone development in children. OBJECTIVES: To assess the impact of a 12-day Baltic Sea (54° N) beach holiday on serum 25-hydroxyvitamin D3 [25(OH)D3 ] and CPD in 32 healthy Polish children (skin types I-IV). METHODS: Blood and urine were collected before and after the holiday and assessed for 25(OH)D3 and excreted CPD, respectively, and personal UVR exposure was measured. Diaries were used to record sunbathing, sunburn and sunscreen use. Before- and after-holiday skin redness and pigmentation were measured by reflectance spectroscopy. RESULTS: The average ± SD daily exposure UVR dose was 2·4 ± 1·5 standard erythema doses (SEDs), which is borderline erythemal. The mean concentration of 25(OH)D3 increased (× 1·24 ± 0·19) from 64·7 ± 13·3 to 79·3 ± 18·7 nmol L-1 (P < 0·001). Mean CPD increased 12·6 ± 10·0-fold from 26·9 ± 17·9 to 248·9 ± 113·4 fmol µmol-1 creatinine (P < 0·001). Increased 25(OH)D3 was accompanied by a very much greater increase in DNA damage associated with carcinogenic potential. Overall, skin type had no significant effects on behavioural, clinical or analytical outcomes, but skin types I/II had more CPD (unadjusted P = 0·0496) than skin types III/IV at the end of the holiday. CONCLUSIONS: Careful consideration must be given to the health outcomes of childhood solar exposure, and a much better understanding of the risk-benefit relationships of such exposure is required. Rigorous photoprotection is necessary for children, even in Northern Europe.

Children's everyday exposure to food marketing: an objective analysis using wearable cameras.

BACKGROUND: Over the past three decades the global prevalence of childhood overweight and obesity has increased by 47%. Marketing of energy-dense nutrient-poor foods and beverages contributes to this worldwide increase. Previous research on food marketing to children largely uses self-report, reporting by parents, or third-party observation of children's environments, with the focus mostly on single settings and/or media. This paper reports on innovative research, Kids'Cam, in which children wore cameras to examine the frequency and nature of everyday exposure to food marketing across multiple media and settings. METHODS: Kids'Cam was a cross-sectional study of 168 children (mean age 12.6 years, SD = 0.5) in Wellington, New Zealand. Each child wore a wearable camera on four consecutive days, capturing images automatically every seven seconds. Images were manually coded as either recommended (core) or not recommended (non-core) to be marketed to children by setting, marketing medium, and product category. Images in convenience stores and supermarkets were excluded as marketing examples were considered too numerous to count. RESULTS: On average, children were exposed to non-core food marketing 27.3 times a day (95% CI 24.8, 30.1) across all settings. This was more than twice their average exposure to core food marketing (12.3 per day, 95% CI 8.7, 17.4). Most non-core exposures occurred at home (33%), in public spaces (30%) and at school (19%). Food packaging was the predominant marketing medium (74% and 64% for core and non-core foods) followed by signs (21% and 28% for core and non-core). Sugary drinks, fast food, confectionary and snack foods were the most commonly encountered non-core foods marketed. Rates were calculated using Poisson regression. CONCLUSIONS: Children in this study were frequently exposed, across multiple settings, to marketing of non-core foods not recommended to be marketed to children. The study provides further evidence of the need for urgent action to reduce children's exposure to marketing of unhealthy foods, and suggests the settings and media in which to act. Such action is necessary if the Commission on Ending Childhood Obesity's vision is to be achieved.

Kids in space: Measuring children's residential neighborhoods and other destinations using activity space GPS and wearable camera data.

INTRODUCTION: Defining the boundary of children's 'neighborhoods' has important implications for understanding the contextual influences on child health. Additionally, insight into activities that occur outside people's neighborhoods may indicate exposures that place-based studies cannot detect. This study aimed to 1) extend current neighborhood research, using data from wearable cameras and GPS devices that were worn over several days in an urban setting; 2) define the boundary of children's neighborhoods by using leisure time activity space data; and 3) determine the destinations visited by children in their leisure time, outside their neighborhoods. METHOD: One hundred and fourteen children (mean age 12y) from Wellington, New Zealand wore wearable cameras and GPS recorders. Residential Euclidean buffers at incremental distances were paired with GPS data (thereby identifying time spent in different places) to explore alternative definitions of neighborhood boundaries. Children's neighborhood boundary was at 500 m. A newly developed software application was used to identify 'destinations' visited outside the neighborhood by specifying space-time parameters. Image data from wearable cameras were used to determine the type of destination. RESULTS: Children spent over half of their leisure time within 500 m of their homes. Children left their neighborhood predominantly to visit school (for leisure purposes), other residential locations (e.g. to visit friends) and food retail outlets (e.g. convenience stores, fast food outlets). Children spent more time at food retail outlets than at structured sport and in outdoor recreation locations combined. CONCLUSION: Person-centered neighborhood definitions may serve to better represent children's everyday experiences and neighborhood exposures than previous methods based on place-based measures. As schools and other residential locations (friends and family) are important destinations outside the neighborhood, such destinations should be taken into account. The combination of image data and activity space GPS data provides a more robust approach to understanding children's neighborhoods and activity spaces.

Children's exposure to alcohol marketing within supermarkets: An objective analysis using GPS technology and wearable cameras.

BACKGROUND AND AIM: Exposure to alcohol marketing within alcohol retailers has been associated with higher rates of childhood drinking, brand recognition, and marketing recall. This study aimed to objectively measure children's everyday exposure to alcohol marketing within supermarkets. METHOD: Children aged 11-13 (n = 167) each wore a wearable camera and GPS device for four consecutive days. Micro-spatial analyses were used to examine exposures within supermarkets. RESULTS: In alcohol retailing supermarkets (n = 30), children encountered alcohol marketing on 85% of their visits (n = 78). Alcohol marketing was frequently near everyday goods (bread and milk) or entrance/exit. CONCLUSION: Alcohol sales in supermarkets should be banned in order to protect children from alcohol marketing.

Assessment of patient-reported outcome and quality of life improvement following surgery for epiphora.

PurposeTo assess and compare the subjective improvement in symptoms and quality of life in adult patients who underwent commonly performed oculoplastic surgical interventions to treat epiphora.Materials and methodsA prospective study was undertaken involving all adult patients undergoing dacryocystorhinostomy (DCR), lid tightening (lateral tarsal strip or lateral wedge resection), and punctoplasty surgery at our institution. We assessed severity of epiphora preoperatively using the Munk score. At 3 months postoperatively, all patients were sent postal questionnaires comprising of Munk score, 'social impact score' from validated Lac-Q questionnaire ranging from 0 (no impact) to 5 (maximal negative impact) and Glasgow Benefit Inventory (GBI) score, ranging from -100 (maximal detriment) to +100 (maximal benefit).ResultsA total of 134 questionnaires were sent with an overall response rate of 74.6%. For the purpose of data analysis, patients were divided into four groups: DCR, lid tightening, punctoplasty, and combined group (lid tightening plus punctoplasty). There was statistically significant improvement in subjective epiphora postoperatively, as assessed by Munk score (P<0.001) in all groups. The total GBI scores were +42.67 (95% CI: 33.42-51.91) for DCR, +19.65 (95% CI: 10.33-28.97) for lid tightening, +16.06 (95% CI: 2.65-29.48) for punctoplasty, and +26.53 (95% CI: 13.15-39.90) for the combined group, demonstrating a positive change in health status for all groups. There was negative correlation between total GBI and post-operative Munk scores (r=-0.58, P<0.001), and positive correlation between Lac-Q and Munk scores (r=0.65, P<0.001).ConclusionPatients derived significant improvement in symptoms and health-related quality of life benefit following all surgical interventions for epiphora.

The value of lacrimal scintillography in the assessment of patients with epiphora.

PurposeTo assess the influence of dacryoscintillography (DSG) on the treatment decision for patients with epiphora and clinically patent non-functioning lacrimal systems.MethodsA retrospective 3-year review. Inclusion: patients having DSG for epiphora with delayed tear clearance, lacrimal system patency on syringing, and no visible external cause for watering. On the basis of regurgitation during syringing, tear ducts were divided into freely patent (FP≤20%) or stenosed. The DSG results were examined for correlation with symptoms and clinical examination, the influence on decision to proceed to dacryocystorhinostomy (DCR), and the ability to predict the surgical outcome.ResultsA total of 242 eyes were examined. The clinical diagnosis was FP in 45.5%, nasolacrimal duct stenosis (NLDS) in 26.4%, and other in 3.3%. The DSG was normal in 30.9% of FP and 18.7% of NLDS eyes. Of the asymptomatic eyes, 46.7% had an abnormal DSG. DSG sensitivity was 73.6% and specificity 53.3%. There was no significant difference in DSG results in those with FP or NLDS.DCR was recommended in 39.1% of the symptomatic eyes with abnormal DSG. DCR surgery was considered inappropriate in all 46 eyes with normal DSG. DCR was successful in 76.5%, however, the DSG result did not affect the success of surgery.ConclusionDSG has severe limitations due to lack of correlation with symptoms and clinical examination, inability to separate lacrimal duct narrowing from lacrimal pump function, and inability to predict the results of surgery. DSG can at best provide limited guidance on whether to proceed to DCR surgery.