Effect of deep transfer learning with a different kind of lesion on classification performance of pre-trained model: Verification with radiolucent lesions on panoramic radiographs

Kise Yoshitaka,Ariji Yoshiko,Kuwada Chiaki,Fukuda Motoki,Ariji Eiichiro 대한영상치의학회 2023 Imaging Science in Dentistry Vol.53 No.1

Purpose: The aim of this study was to clarify the influence of training with a different kind of lesion on the perfor- mance of a target model. Materials and Methods: A total of 310 patients (211 men, 99 women; average age, 47.9±16.1 years) were selected and their panoramic images were used in this study. We created a source model using panoramic radiographs including mandibular radiolucent cyst-like lesions (radicular cyst, dentigerous cyst, odontogenic keratocyst, and ameloblastoma). The model was simulatively transferred and trained on images of Stafne’s bone cavity. A learning model was created using a customized DetectNet built in the Digits version 5.0 (NVIDIA, Santa Clara, CA). Two machines (Machines A and B) with identical specifications were used to simulate transfer learning. A source model was created from the data consisting of ameloblastoma, odontogenic keratocyst, dentigerous cyst, and radicular cyst in Machine A. Thereafter, it was transferred to Machine B and trained on additional data of Stafne’s bone cavity to create target models. To investigate the effect of the number of cases, we created several target models with different numbers of Stafne’s bone cavity cases. Results: When the Stafne’s bone cavity data were added to the training, both the detection and classification performances for this pathology improved. Even for lesions other than Stafne’s bone cavity, the detection sensitivities tended to increase with the increase in the number of Stafne’s bone cavities. Conclusion: This study showed that using different lesions for transfer learning improves the performance of the model.

만성경화성 하악골골수염의 임상적검토

KUROIWA Yuichiro,MATSUURA Hiroaki,ABE Atsushi,KATO Mugio,ARIJI Yoshiko,KURITA Kenichi 대한구강악안면외과학회 2008 대한구강악안면외과학회지 Vol.34 No.3

Mandibular chronic osteomyelitis with diffuse osteosclerosis is recognized as an intractable infectious disease. We emplyed decortication and intraarterial infusion of antibiotics in 6 cases. Decortication on the affected mandible was performed with retrocatherization to the superficial temporal artery of affected side under general anesthesia. Antibiotics, IPM/CS or FOMX was used through the artery for 4-11 days. In addition, we administered FOMX, PIPC intravenously for 8-17 days. CT and MRI were taken postoperatively. The postoperative follow-up period ranged from 1 year and 6 months to 2 years and 5 months. Postoperative MR showed that bone marrow signal was recovered to approximately normal in 4 cases. High signal area of bone marrow and osteosclerosis image remained in 2 cases, but showed improvement. The results were satisfactory without recurrence in all of 6 cases.

Deep learning system for distinguishing between nasopalatine duct cysts and radicular cysts arising in the midline region of the anterior maxilla on panoramic radiographs

Kise Yoshitaka,Kuwada Chiaki,Mori Mizuho,Fukuda Motoki,Ariji Yoshiko,Ariji Eiichiro 대한영상치의학회 2024 Imaging Science in Dentistry Vol.54 No.1

Purpose: The aims of this study were to create a deep learning model to distinguish between nasopalatine duct cysts (NDCs), radicular cysts, and no-lesions (normal) in the midline region of the anterior maxilla on panoramic radiographs and to compare its performance with that of dental residents. Materials and Methods: One hundred patients with a confirmed diagnosis of NDC (53 men, 47 women; average age, 44.6±16.5 years), 100 with radicular cysts (49 men, 51 women; average age, 47.5±16.4 years), and 100 with normal groups (56 men, 44 women; average age, 34.4±14.6 years) were enrolled in this study. Cases were randomly assigned to the training datasets (80%) and the test dataset (20%). Then, 20% of the training data were randomly assigned as validation data. A learning model was created using a customized DetectNet built in Digits version 5.0 (NVIDIA, Santa Clara, USA). The performance of the deep learning system was assessed and compared with that of two dental residents. Results: The performance of the deep learning system was superior to that of the dental residents except for the recall of radicular cysts. The areas under the curve (AUCs) for NDCs and radicular cysts in the deep learning system were significantly higher than those of the dental residents. The results for the dental residents revealed a significant difference in AUC between NDCs and normal groups. Conclusion: This study showed superior performance in detecting NDCs and radicular cysts and in distinguishing between these lesions and normal groups.

Effects of 1 year of training on the performance of ultrasonographic image interpretation: A preliminary evaluation using images of Sjogren syndrome patients

Kise, Yoshitaka,Moystad, Anne,Bjornland, Tore,Shimizu, Mayumi,Ariji, Yoshiko,Kuwada, Chiaki,Nishiyama, Masako,Funakoshi, Takuma,Yoshiura, Kazunori,Ariji, Eiichiro Korean Academy of Oral and Maxillofacial Radiology 2021 Imaging Science in Dentistry Vol.51 No.2

Purpose: This study investigated the effects of 1 year of training on imaging diagnosis, using static ultrasonography (US) salivary gland images of Sjögren syndrome patients. Materials and Methods: This study involved 3 inexperienced radiologists with different levels of experience, who received training 1 or 2 days a week under the supervision of experienced radiologists. The training program included collecting patient histories and performing physical and imaging examinations for various maxillofacial diseases. The 3 radiologists (observers A, B, and C) evaluated 400 static US images of salivary glands twice at a 1-year interval. To compare their performance, 2 experienced radiologists evaluated the same images. Diagnostic performance was compared between the 2 evaluations using the area under the receiver operating characteristic curve (AUC). Results: Observer A, who was participating in the training program for the second year, exhibited no significant difference in AUC between the first and second evaluations, with results consistently comparable to those of experienced radiologists. After 1 year of training, observer B showed significantly higher AUCs than before training. The diagnostic performance of observer B reached the level of experienced radiologists for parotid gland assessment, but differed for submandibular gland assessment. For observer C, who did not complete the training, there was no significant difference in the AUC between the first and second evaluations, both of which showed significant differences from those of the experienced radiologists. Conclusion: These preliminary results suggest that the training program effectively helped inexperienced radiologists reach the level of experienced radiologists for US examinations.

Differences in the panoramic appearance of cleft alveolus patients with or without a cleft palate

Fujii Takeshi,Kuwada Chiaki,Kise Yoshitaka,Fukuda Motoki,Mori Mizuho,Nishiyama Masako,Nozawa Michihito,Naitoh Munetaka,Ariji Yoshiko,Ariji Eiichiro 대한영상치의학회 2024 Imaging Science in Dentistry Vol.54 No.1

Purpose: The purpose of this study was to clarify the panoramic image differences of cleft alveolus patients with or without a cleft palate, with emphases on the visibility of the line formed by the junction between the nasal septum and nasal floor (the upper line) and the appearances of the maxillary lateral incisor. Materials and Methods: Panoramic radiographs of 238 patients with cleft alveolus were analyzed for the visibility of the upper line, including clear, obscure or invisible, and the appearances of the maxillary lateral incisor, regarding congenital absence, incomplete growth, delayed eruption and medial inclination. Differences in the distribution ratio of these visibility and appearances were verified between the patients with and without a cleft palate using the chi- square test. Results: There was a significant difference in the visibility distribution of the upper line between the patients with and without a cleft palate (p<0.05). In most of the patients with a cleft palate, the upper line was not observed. In the unilateral cleft alveolus patients, the medial inclination of the maxillary lateral incisor was more frequently observed in patients with a cleft palate than in patients without a cleft palate. Conclusion: Two differences were identified in panoramic appearances. The first was the disappearance (invisible appearance) of the upper line in patients with a cleft palate, and the second was a change in the medial inclination on the affected side maxillary lateral incisor in unilateral cleft alveolus patients with a cleft palate.