Automated and observer based light field indicator edge evaluation in diagnostic X-ray equipment

Abstract Introduction To analyze edge detection and optical contrast calculation of light field-indicators used in X-ray via automated- and observer-based methods, and comparison with current standard approaches, which do not give exact definition for light field edge determination. Methods Automated light sensor array was used to measure the penumbra zone of the edge in the standard X-ray equipment, while trained and naïve human observers were asked to mark the light field edge according to their own determination. Different interpretations of the contrast were then calculated and compared. Results In contrast to automated measurements of edge definition and detection, measurements by human observers showed large inter-observer variation independent of their training with X-ray equipment. Different contrast calculations considering the different edge definitions gave very different contrast values. Conclusion As the main conclusion, we propose a more exact edge definition of the X-ray light field, corresponding well to the average human observer's edge determination. The new edge definition method with automated systems would reduce human variability in edge determination. Such errors could potentially affect the approval of X-ray equipment, and also increase the radiation dose. The automated measurement based on human observers' edge definition and the corresponding contrast calculation may lead to a more precise light field calibration, which enables reduced irradiation doses on radiology patients.

Rare finding of Eustachian tube calcifications with cone-beam computed tomography

Soft tissue calcification is a pathological condition in which calcium and phosphate salts are deposited in the soft tissue organic matrix. This study presents an unusual calcification noted in the cartilaginous portion of the Eustachian tube. A 67-year-old woman presented for dental treatment, specifically for implant placement, and cone-beam computed tomography (CBCT) was performed. The CBCT scan was reviewed by a board-certified oral and maxillofacial radiologist and revealed incidental findings of 2 distinct calcifications in the cartilaginous portion of the Eustachian tube. To the authors' knowledge, no previous study has reported the diagnosis of Eustachian tube calcification using CBCT. This report describes an uncommon variant of Eustachian tube calcification, which has a significant didactic value because such cases are seldom illustrated either in textbooks or in the literature. This case once again underscores the importance of having CBCT scans evaluated by a board-certified oral and maxillofacial radiologist.

Prevalence of orofacial alterations in sickle cell disease: a review of literature

AIM: To evaluate the manifestations of sickle cell disease on the orofacial complex through a review of current literature concerning prevalence of dental caries, periodontal disease, temporomandibular joint disorders and radiographic alterations of maxillofacial bones. METHODS: Full-text papers retrieved from MEDLINE and LILACS electronic databases were critically reviewed. RESULTS: Alterations of maxillofacial bones are well documented in the literature, but studies reporting caries, periodontal condition and temporomandibular joint alterations in are scarce and inconclusive. CONCLUSION: Further well-designed epidemiological studies are needed to indicate the real impact of this disease on the stomatognathic health, collaborating to improve public health policies.