Exploration of Digital Health Technologies

Table 1. Photography-based diagnostic models

Author, year	Task; classes (n)	Feature extractors/Features extracted	Classifier	Accuracy	Specificity (TNR)	Sensitivity (recall)	Precision (PPV)	AUC	F1-score or Jaccard index
Camalan et al. [1], 2021	Classification; suspicious (54) and normal (54) ROIs in photographic images	-	Inception ResNet-v2	86.5%	-	-	-	-	-
Camalan et al. [1], 2021		-	ResNet-101	79.3%	-	-	-	-	-
Figueroa et al. [2], 2022	Classification; suspicious (i.e., OSCC and OPMD) (~ 2,800) and normal (~ 2,800) photographic images	-	GAIN network	84.84%	89.3%	76.6%	-	-	-
Flügge et al. [3], 2023	Classification; OSCC (703) and normal (703) photographic images	-	Swin-transformer DL network	0.98	0.98	0.98	-	-	0.98
Jubair et al. [4], 2022	Classification; suspicious [i.e., OSCC and OPMD (236)] and benign (480) photographic images	-	EfficientNetB0	85%	84.5%	-	-	0.92	-
Jurczyszyn et al. [5], 2020	Classification; OSCC (35) and normal (35) photographic images (1 normal and one of leukoplakia in the same patient)	MaZda software/Textural features, as run length matrix (two), co-occurrence matrix (two), Haar Wavelet transformation (two)	Probabilistic neural network	-	97%	100%	-	-	-
Lim et al. [6], 2021	Classification; no referral (493), refer—cancer/high-risk (636), refer—low-risk (685), and refer—other reasons (641)	-	ResNet-101	-	-	61.70%	61.96%	-	61.68%
Shamim et al. [7], 2019	Classification; benign and precancerous (200) photographic images	-	VGG19	98%	97%	89%	-	-	-
			AlexNet	93%	94%	88%	-	-	-
			GoogLeNet	93%	88%	80%	-	-	-
			ResNet50	90%	96%	84%	-	-	-
			Inceptionv3	93%	88%	83%	-	-	-
			SqueezeNet	93%	96%	85%	-	-	-
	Classification; types of tongue lesions (300) photographic images	-	VGG19	97%	-	-	-	-	-
			AlexNet	83%	-	-	-	-	-
			GoogLeNet	88%	-	-	-	-	-
			ResNet50	97%	-	-	-	-	-
			Inceptionv3	92%	-	-	-	-	-
			SqueezeNet	90%	-	-	-	-	-
Sharma et al. [8], 2022	Classification; OSCC (121), OPMD (102) and normal (106) photographic images	-	VGG19	76%	-	OSCC: 0.43	OSCC: 0.76	OSCC: 0.92	OSCC: 0.45
					-	Normal: 1	Normal: 0.9	Normal: 0.99	Normal: 0.95
					-	OPMD: 0.78	OPMD: 0.7	OPMD: 0.88	OPMD: 0.74
			VGG16	72%	-	-	-	OSCC: 0.94	-
					-	-	-	Normal: 0.96	-
					-	-	-	OPMD: 0.92	-
			MobileNet	72%	-	-	-	OSCC: 0.88	-
					-	-	-	Normal: 0.99	-
					-	-	-	OPMD: 0.80	-
			InceptionV3	68%	-	-	-	OSCC: 0.88	-
					-	-	-	Normal: 0.1	-
					-	-	-	OPMD: 0.88	-
			ResNet50	36%	-	-	-	OSCC: 0.43	-
					-	-	-	Normal: 0.33	-
					-	-	-	OPMD: 0.42	-
Song et al. [9], 2021	Classification; malignant (911), premalignant (1,100), benign (243) and normal (2,417) polarized white light photographic images	-	VGG19	80%	-	79%	83%	-	81%
Song et al. [10], 2023	Classification; suspicious (1,062), normal (978) photographic images	-	SE-ABN	87.7%	88.6%	86.8%	87.5%	-	-
Song et al. [10], 2023			SE-ABN + manually edited attention maps	90.3%	90.8%	89.8%	89.9%	-	-
Tanriver et al. [11], 2021	Segmentation, object detection and classification; carcinoma (162), OPMD (248) and benign (274) photographic images	-	EfficientNet-b4	-	-	85.5%	86.9%	-	85.8%
			Inception-v4	-	-	85.5%	87.7%	-	85.8%
			DenseNet-161	-	-	84.1%	87.9%	-	84.4%
			ResNet-152	-	-	81.2%	82.6%	-	81.1%
			Ensemble	-	-	84.1%	84.9%	-	84.3%
Thomas et al. [12], 2013	Classification; 192 sections of photographic images from 16 patients	GLCM, GLRL and intensity based first order features (eleven selected features)	Backpropagation based ANN	97.92%	-	-	-	-	-
Warin et al. [13], 2021	Object detection and classification; OPMD (350) and normal (350) photographic images	-	DenseNet-121	-	100%	98.75%	99%	0.99	99%
Warin et al. [14], 2022	Object detection and classification; OPMD (315) and OSCC (365) photographic images	-	DenseNet-169	-	OSCC: 99%	OSCC: 99%	OSCC: 98%	OSCC: 1	OSCC: 98%
			DenseNet-169	-	OPMD: 97%	OPMD: 95%	OPMD: 95%	OPMD: 0.98	OPMD: 95%
			ResNet-101	-	OSCC: 94%	OSCC: 92%	OSCC: 96%	OSCC: 0.99	OSCC: 94%
			ResNet-101	-	OPMD: 94%	OPMD: 97%	OPMD: 97%	OPMD: 0.97	OPMD: 97%
Warin et al. [15], 2022	Object detection and classification; OPMD (300) and normal (300) photographic images	-	DenseNet-121	-	90%	100%	91%	0.95	95%
Warin et al. [15], 2022		-	ResNet-50	-	91.67%	98.39%	92%	0.95	95%
Welikala et al. [16], 2020	Object detection and classification; referral (1,054) and non-referral (379) photographic images	-	ResNet-101	-	-	93.88%	67.15%	-	78.30%
Xue et al. [17], 2022	Classification; ruler (440) and non-ruler (2,377) photographic images; first batch (2,817 images/250 patients), second batch (4,331 images/168 patients)	-	ResNetSt	99.6%	99.6%	100%	97.9%	99.6%	98.9%
Xue et al. [17], 2022		-	Vit	99.8%	99.8%	100%	0.98	99.8%	99.5%

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ANN: artificial neural network; DL: deep learning; GAIN: guided attention inference; GLCM: gray-level co-occurrence matrix; GLRL: grey level run-length matrix; OPMD: oral potentially malignant disorders; OSCC: oral squamous cell carcinoma; PPV: positive predictive value; ROI: region of interest; TNR: true negative rate; AUC: area under the curv

Declarations

Acknowledgments

During the preparation of this work the authors used ChatGPT (March 14 version) from OpenAI (https://chat.openai.com/chat) in order to specifically review grammar and spelling. After using this tool/service, the authors reviewed and edited the content as needed and took full responsibility for the content of the publication. No large language models/tools/services were used to analyze and draw insights from data as part of the research process.

Author contributions

ALDA: Conceptualization, Investigation, Writing—original draft, Writing—review & editing. CMP: Writing—review & editing. PAV: Writing—review & editing. MAL: Writing—review & editing. ARSS: Conceptualization, Writing—review & editing.

Conflicts of interest

The authors declare that there are no conflicts of interest.

Ethical approval

This study is in accordance with the Declaration of Helsinki and was approved by the Piracicaba Dental Ethical Committee, Registration number: 42235421.9.0000.5418.

Consent to participate

The informed consent to participate in the study was obtained from all participants.

Consent to publication

Informed consent to publication was obtained from relevant participants.

Availability of data and materials

Not applicable.

Funding

This study was financed, in part, by the São Paulo Research Foundation (FAPESP) [#2021/14585-7, #2022/07276-0], Brasil. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Copyright

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