SynthEye: Investigating the Impact of Synthetic Data on Artificial Intelligence-assisted Gene Diagnosis of Inherited Retinal Disease

Purpose: Rare disease diagnosis is challenging in medical image-based artificial intelligence due to a natural class imbalance in datasets, leading to biased prediction models. Inherited retinal diseases (IRDs) are a research domain that particularly faces this issue. This study investigates the applicability of synthetic data in improving artificial intelligence-enabled diagnosis of IRDs using generative adversarial networks (GANs). Design: Diagnostic study of gene-labeled fundus autofluorescence (FAF) IRD images using deep learning. Participants: Moorfields Eye Hospital (MEH) dataset of 15 692 FAF images obtained from 1800 patients with confirmed genetic diagnosis of 1 of 36 IRD genes. Methods: A StyleGAN2 model is trained on the IRD dataset to generate 512 × 512 resolution images. Convolutional neural networks are trained for classification using different synthetically augmented datasets, including real IRD images plus 1800 and 3600 synthetic images, and a fully rebalanced dataset. We also perform an experiment with only synthetic data. All models are compared against a baseline convolutional neural network trained only on real data. Main Outcome Measures: We evaluated synthetic data quality using a Visual Turing Test conducted with 4 ophthalmologists from MEH. Synthetic and real images were compared using feature space visualization, similarity analysis to detect memorized images, and Blind/Referenceless Image Spatial Quality Evaluator (BRISQUE) score for no-reference-based quality evaluation. Convolutional neural network diagnostic performance was determined on a held-out test set using the area under the receiver operating characteristic curve (AUROC) and Cohen’s Kappa (κ). Results: An average true recognition rate of 63% and fake recognition rate of 47% was obtained from the Visual Turing Test. Thus, a considerable proportion of the synthetic images were classified as real by clinical experts. Similarity analysis showed that the synthetic images were not copies of the real images, indicating that copied real images, meaning the GAN was able to generalize. However, BRISQUE score analysis indicated that synthetic images were of significantly lower quality overall than real images (P < 0.05). Comparing the rebalanced model (RB) with the baseline (R), no significant change in the average AUROC and κ was found (R-AUROC = 0.86[0.85-88], RB-AUROC = 0.88[0.86-0.89], R-k = 0.51[0.49-0.53], and RB-k = 0.52[0.50-0.54]). The synthetic data trained model (S) achieved similar performance as the baseline (S-AUROC = 0.86[0.85-87], S-k = 0.48[0.46-0.50]). Conclusions: Synthetic generation of realistic IRD FAF images is feasible. Synthetic data augmentation does not deliver improvements in classification performance. However, synthetic data alone deliver a similar performance as real data, and hence may be useful as a proxy to real data.Financial Disclosure(s): Proprietary or commercial disclosure may be found after the references

Avaliação da concordância interobservadores na análise da polipose nasossinusal por meio da tomografia computadorizada Evaluation of the concordance between observers in sinunasal polyposis through computed tomographic analysis

Polipose nasossinusal (PNS) é uma entidade de etiologia controversa, caracterizada por uma condição inflamatória da superfície mucosa das fossas nasais e seios paranasais, bilateralmente. A queixa principal do paciente consiste na obstrução nasal e, ao exame físico, observam-se freqüentemente massas polipóides ocupando as cavidades nasais em extensões variáveis. Além da rinoscopia anterior e da endoscopia nasal, o uso da tomografia computadorizada (TC) torna-se necessário para avaliação das fossas nasais e da presença ou não do acometimento dos seios paranasais por essas massas, bem como a sua extensão. Este trabalho tem como objetivo avaliar a concordância interobservadores, por meio da análise da tomografia computadorizada, de 32 casos de PNS. FORMA DE ESTUDO: Clínico prospectivo. CASUÍSTICA E MÉTODOS: Foram avaliadas 32 TC de pacientes portadores PNS por dois observadores experientes, separadamente, em relação à presença ou não de 3 sinais tomográficos sugestivos dessa doença: (1) alargamento infundibular do complexo ostiomeatal, (2) abaulamento lateral da lâmina papirácea e (3) apagamento do trabeculado ósseo etmoidal. RESULTADOS: Observou-se Qui-quadrado não significante para o primeiro e segundo sinais (p=0,7055 e p=0,2057) e significante para o terceiro (p=0,0040). Contudo, o coeficiente de correlação de Kendall entre os dois observadores foi significante para os três sinais tomográficos acima citados (p<0,001; p=0,01; p=0,03 respectivamente). CONCLUSÃO: A maior concordância entre os observadores esteve presente no alargamento infundibular com maior freqüência de positividade desse sinal.<br>Sinonasal polyposis (SNP) is a condition with a controversial aethiology, known by bilaterally inflammatory mucous membranes of nasal and paranasal sinuses. The major patient's complaint is nasal obstruction, and polypoid masses in different sizes can be found during nasal cavity examination. Beyond anterior rhinoscophy and nasal endoscopy, screening sinus computed tomography (SSCT) is necessary to measure the size and the extent of the polyps into nasal cavities and paranasal sinuses. The purpose of this study is to evaluate the concordance between two observers through SSCT of 32 cases with SNP. STUDY DESIGN: Clinical prospective. MATERIAL AND METHOD: CT scans were evaluated separately by two experts, taking into consideration three suggestive tomography signs of SNP: (1) Infundibular enlargement of ostiomeatal complex; (2) bulging of lamina papyracea and (3) bony attenuation of ethmoid trabeculae. RESULTS: Qui-square was not significant for either the first or the second signs (p=0,7055 and p=0,2057), but for the third one (p=0,0040). However, Kendall coefficient between the two observers was significant for all the three tomography signs mentioned before (p<0,001; p=0,01; p=0,03). CONCLUSION: The major concordance between the observers concerned the infundibular enlargement, which was also the most frequent sign