Rapid Grading of Fundus Photographs for Diabetic Retinopathy Using Crowdsourcing

Background

Screening for diabetic retinopathy is both effective and cost-effective, but rates of screening compliance remain suboptimal. As screening improves, new methods to deal with screening data may help reduce the human resource needs. Crowdsourcing has been used in many contexts to harness distributed human intelligence for the completion of small tasks including image categorization.

Objective

Our goal was to develop and validate a novel method for fundus photograph grading.

Methods

An interface for fundus photo classification was developed for the Amazon Mechanical Turk crowdsourcing platform. We posted 19 expert-graded images for grading by Turkers, with 10 repetitions per photo for an initial proof-of-concept (Phase I). Turkers were paid US $0.10 per image. In Phase II, one prototypical image from each of the four grading categories received 500 unique Turker interpretations. Fifty draws of 1-50 Turkers were then used to estimate the variance in accuracy derived from randomly drawn samples of increasing crowd size to determine the minimum number of Turkers needed to produce valid results. In Phase III, the interface was modified to attempt to improve Turker grading.

Results

Across 230 grading instances in the normal versus abnormal arm of Phase I, 187 images (81.3%) were correctly classified by Turkers. Average time to grade each image was 25 seconds, including time to review training images. With the addition of grading categories, time to grade each image increased and percentage of images graded correctly decreased. In Phase II, area under the curve (AUC) of the receiver-operator characteristic (ROC) indicated that sensitivity and specificity were maximized after 7 graders for ratings of normal versus abnormal (AUC=0.98) but was significantly reduced (AUC=0.63) when Turkers were asked to specify the level of severity. With improvements to the interface in Phase III, correctly classified images by the mean Turker grade in four-category grading increased to a maximum of 52.6% (10/19 images) from 26.3% (5/19 images). Throughout all trials, 100% sensitivity for normal versus abnormal was maintained.

Conclusions

With minimal training, the Amazon Mechanical Turk workforce can rapidly and correctly categorize fundus photos of diabetic patients as normal or abnormal, though further refinement of the methodology is needed to improve Turker ratings of the degree of retinopathy. Images were interpreted for a total cost of US $1.10 per eye. Crowdsourcing may offer a novel and inexpensive means to reduce the skilled grader burden and increase screening for diabetic retinopathy.     

Transport of infants with congenital heart disease: benefits of antenatal diagnosis

Infants with significant congenital heart disease (CHD) typically require transport from their birth centre to a regional paediatric cardiac centre. Antenatal diagnosis of CHD allows early pre-emptive stabilisation, and is associated with improved early clinical status. However, the effect of antenatal diagnosis on the transport characteristics of infants with CHD has not been previously investigated. The aim of this study was to compare the transport characteristics of infants with antenatal and postnatal diagnosis of CHD. This study is a retrospective cohort study of all infants of ≤10 days and ≥34 weeks of gestation with CHD admitted to the Royal Children's Hospital, Melbourne (RCH) over 5 years. Demographic, diagnosis, and transport data were recorded. Cases of complex CHD were included in this study. Of 320 infants with complex CHD, 198 (62 %) had antenatal diagnosis (ANdx) and 122 (38 %) had postnatal diagnosis (PNdx). There was no significant difference in sex, birth weight, or gestation between ANdx and PNdx groups. Average age of referral was 15 vs. 53.4 h in ANdx vs. PNdx groups. Aggregate transfer distance in the ANdx group was 2216 km and in the PNdx group was 10,274 km (P?<?0.0001). Of the infants, 39 % in the PNdx group required highest-acuity “time critical” transports compared to 6 % of ANdx infants (P?=?0.0001). Conversely, only 11 % of the infants in the PNdx group had lowest acuity “non-urgent” transfers, compared to 24 % of ANdx infants (P?=?0.003). PNdx was associated with significantly higher rates of invasive ventilation (36 vs 20 %; P?=?0.01) and higher rates of inotrope use (19 vs. 9 %; P?=?0.007) during transport. Conclusions: Improved antenatal detection would allow for safer, less resource intense transfers of infants with CHD.     

The great divide: septation and malformation of the cloaca,and its implications for surgeons

The anorectal and urogenital systems arise from a common embryonic structure termed cloaca. Subsequent development leads to the division/septation of the cloaca into the urethra, urinary bladder, vagina, anal canal, and rectum. Defective cloacal development and the resulting anorectal and urogenital malformations are some of the most severe congenital anomalies encountered in children. In the most severe form in females, the rectum, vagina, and urethra fail to develop separately and drain via a single common channel known as a cloaca into the perineum. In this review, we summarize our current knowledge of embryonic cloaca development and malformation, and compare them to what has already been described in the literature. We describe the use of mouse models of cloaca malformation to understand which signaling pathways and cellular mechanisms are involved in the process of normal cloaca development. We also discuss the embryological correlation of the epithelial and stromal histology found in step sections of the common channel in 14 human cloaca malformations. Finally, we highlight the significance of these findings, compare them to prior studies, and discuss their implications for the pediatric surgeons. Understanding and identifying the molecular basis for cloaca malformation could provide foundation for tissue engineering efforts that in the future would reflect better surgical reconstruction and improved quality of life for patients.     

A Rare Case of Hemolytic Anemia in a Pediatric Patient Due to Ring Dehiscence After Mitral Valve Repair: Utility of Real-Time Three-Dimensional Imaging and Management

A rare case of hemolytic anemia in a 3-year-old child due to mitral valve ring dehiscence is described. The dehiscence of mitral valve ring was diagnosed utilizing real-time three-dimensional echocardiography. The patient subsequently underwent reoperation with successful resolution of hemolysis after replacement of the ring.     

Experience of 100 solid organ transplants over a five‐yr period from the first successful pediatric multi‐organ transplant program in India

To analyze the clinical profile and outcome of pediatric patients who had undergone a liver and/or RT at our center over a five yr period, case records of all the patients who had undergone a liver or RT were analyzed retrospectively. One hundred solid organ transplants were performed at our center between January 2007 and January 2012. These included 50 liver, 44 renal, one sequential liver and renal, and two CLKT. BA was the most common indication for an LT (38%). At a median follow‐up of two yr three months, the patient survival was 88%. The most common indication for an RT was chronic glomerulonephritis (54.5%). At a median follow‐up of three yr, the survival was 91%. The CLKT were performed for hyperoxaluria. Two yr post LT, a sequential RT was performed for ESRD resulting from transplant associated microangiopathy. All patients received a living related graft. The common post‐operative complications were infections, vascular complications, and graft dysfunction. Survival rates for liver and RT at our center are comparable to those in the established centers in the West.     

Coincidental diagnosis of tuberculous lymphadenitis: a case report

The aim of this case report was to present a case of multiple calcified tuberculous lymph nodes found on a panoramic radiograph coincidently diagnosed in an endodontic clinic. A detailed discussion on the differential diagnosis of similar such calcification found in the same region is also presented. A 14‐year‐old girl was referred to our department with the complaint of painless swelling in the left side of the lower jaw. Clinical and radiographical examinations were performed, leading to the initial diagnosis of chronic periapical abscess. The patient's medical history was re‐evaluated. Advanced imaging and excisional biopsy were performed in order to confirm the final diagnosis. Regarding the presenting signs and symptoms of bilateral carious mandibular molars, a periapical inflammatory process was considered in the provisional diagnosis. A thorough examination and investigations were suggestive of cervical tuberculous lymphadenitis (scrofula), and the patient underwent excision of the same. The clinician should consider the possibility of chronic granulomatous inflammatory lesions in the differential diagnosis of radiopaque lesions.     

Efficacy of Preprocedural Mouth Rinsing in Reducing Aerosol Contamination Produced by Ultrasonic Scaler: A Pilot Study

Background: The aerosol generated by an ultrasonic scaler contains microorganisms that can penetrate into the body through the respiratory system of dental surgeons and patients. The aim of this pilot study is to evaluate and compare the efficacy of commercially available preprocedural mouthrinses containing 0.2% chlorhexidine gluconate, an herbal mouthwash, and water in reducing the levels of viable bacteria in aerosols. Methods: This single‐center, double‐masked, placebo‐controlled, randomized, three‐group parallel design was conducted over a period of 45 days. Twenty‐four patients with chronic periodontitis were divided randomly into three groups (A, B, and C) of eight patients each to receive 0.2% chlorhexidine gluconate, herbal mouthwash, and water, respectively, as a preprocedural rinse. The aerosol produced by the ultrasonic unit was collected at patient's chest area, doctor's chest area, and assistant's chest area on blood agar plates in all three groups. The blood agar plates were incubated at 37°C for 48 hours, and the total number of colony‐forming units (CFUs) was counted and statistically analyzed. Results: The results showed that CFUs in groups A and B were significantly reduced compared with group C, P <0.001 (analysis of variance). Also, CFUs in group A were significantly reduced compared with group B, P <0.05 (independent t‐test). The numbers of CFUs were highest at the patient's chest area and lowest at the assistant's chest area. Conclusion: This study suggests that a routine preprocedural mouthrinse could eliminate the majority of bacterial aerosols generated by the use of an ultrasonic unit, and that 0.2% chlorhexidine gluconate is more effective than herbal mouthwash.     

Management of Odontogenic Space Infection with Microbiology Study

Introduction

Dental infection has plagued humankind for as long as our civilization has been a fight against microorganisms by man dates back to ancient civilization. The discoveries of antibiotics are encouraging trends towards conquest of the microbial infection.

Materials and Methods

This study emphasizes the detection of pathogenic microorganisms by microbiological examination and culture of specimens representative of the infection, importance of early and correct diagnosis of infections, prompt treatment and supportive care.

Results

The age group most commonly involved was in the third and fourth decades of life. Extraction followed by incision and drainage was done. The most commonly involved space was submandibular followed by buccal space. Thirty isolates were obtained. 43 % of the strains were strict anaerobes and 39 % were aerobes, with mixed growth was seen in 18.52 %. Amongst aerobes alpha hemolytic Streptococcus aureus and Peptostreptococcus as anaerobes were the most predominant followed by Bacteroides and Prevotella. Mixed aerobic and anaerobic isolates were obtained from 18.52 % of total cases. Overall resistance to Penicillin was 22 %, amongst aerobes.

Conclusion

Amoxicillin and Clavulanic acid combination performed better, as 100 % strains were sensitive to it. The results of this study saw a changing trend in terms of predominance of anaerobic bacteria over aerobic ones.