Deep learning-based classification of dermatological lesions given a limited amount of labeled data

BACKGROUND

Artificial intelligence (AI) techniques are promising in early diagnosis of skin diseases. However, a precondition for their success is the access to large-scaled annotated data. Until now, obtaining this data has only been feasible with very high personnel and financial resources.

OBJECTIVES

The aim of this study was to overcome the obstacle caused by the scarcity of labeled data.

METHODS

To simulate the scenario of label shortage, we discarded a proportion of labels of the training set. The training set consisted of both labeled and unlabeled images. We then leveraged a self-supervised learning technique to pre-train the AI model on the unlabeled images. Next, we fine-tuned the pre-trained model on the labeled images.

RESULTS

When the images in the training dataset were fully labeled, the self-supervised pre-trained model achieved 95.7% of accuracy, 91.7% of precision and 90.7% of sensitivity. When only 10% of the data was labeled, the model could still yield 87.7% of accuracy, 81.7% of precision and 68.6% of sensitivity. In addition, we also empirically verified that the AI model and dermatologists are consistent in visually inspecting the skin images.

CONCLUSIONS

The experimental results demonstrate the great potential of the self-supervised learning in alleviating the scarcity of annotated data.

Quality of life following aesthetic plastic surgery: a prospective study

BACKGROUND

The objective of this study was the prospective evaluation of quality of life in patients undergoing aesthetic plastic surgery procedures. We examined pre- and postoperative changes in quality of life, and performed a comparison of our data with a representative random sample.

METHOD

228 patients agreed to participate in the present study. Measurements were taken preoperatively as well as 3 and 6 months postoperatively. One hundred and thirty two patients completed the three months postoperative evaluation (T1), 82 answered the 6 months follow-up evaluation (T2). The testing instrument included a standardised self-assessment test on satisfaction and quality of life (FLZ(M)), consisting of three modules: satisfaction with general life, health and appearance. Further, a postoperative complication questionnaire was used in order to evaluate the satisfaction with the surgical outcome and to estimate postoperative complications and side effects.

RESULTS

Significantly increasing values in two aspects of quality of life were found: health and appearance. Whereas the positive influence on health is persistent, there is a diminishing influence of appearance 6 months postoperatively. Although higher values for some of the individual items of the FLZ(M) modules of the norm data were found in comparison to our study group, a general preoperative lower level of quality of life of the aesthetic surgery patients could not be confirmed. Over 84% were satisfied or very satisfied with the aesthetic result. 85% would undergo the same treatment again and 94% of the patients would further recommend their operation. More than half of the study group did not report a decrease in physical fitness or reduced social contacts in the direct postoperative period.

CONCLUSION

Our study reveals that aesthetic plastic surgery increases most aspects of quality of life, especially regarding body satisfaction and health. It is very well tolerated by the patients and is therefore a recommended option.

Blood vitamin concentrations in privately owned dogs fed non-standardized commercial diets and after intake of diets with specified vitamin concentrations

The objective was to investigate in a survey study the blood vitamin concentrations in healthy dogs fed non-specified commercial complete diets and in an intervention study to determine the effects of defined dietary vitamin intakes on blood vitamin levels and hair and skin condition. Sixty-four privately owned dogs, aged from 1 to 8 years, without history of skin or coat problems were included. All animals were fed commercial complete diets with uncertain vitamin concentrations before enrolment. The animals were assigned, according to weight and gender, to four groups with graded vitamin intakes. The blood vitamin levels and skin and coat quality of the dogs were investigated at days 0 and day 122. Coat and hair condition was not influenced by the experimental diets. The retinol concentrations were reduced at the end of the experiment compared with the baseline levels, retinyl esters were not influenced. 25-Hydroxycholecalciferol decreased in all groups, alpha-tocopherol was constant or tended to decrease. Ascorbic acid, thiamine pyrophosphate and riboflavin concentrations were not affected by treatment, flavin adenine dinucleotide and pyridoxal-5'-phosphate were partially reduced on day 122. Cobalamin, pantothenate and biotin concentrations increased with higher dietary intakes, folate levels in tendency. In conclusion, this study gives a survey of blood vitamin concentrations in healthy dogs and provides a data base for the evaluation of the vitamin status in health and disease.