Gray scale inversion in digital image for measurement of tooth length

Does T2 inversion aid in identifying disc pathologies?

OBJECTIVE

T2 inversion sequence is used in routine radiology practice mainly to heighten contrast resolution within the region to be studied but no evidence exists in current literature to assess it's true efficacy for lumbar disc degeneration. The objective of this study was to analyse T2 inversion and evaluate it's efficacy in assessment of lumbar disc pathology,.

MATERIALS AND METHODS

This retrospective single-centre study included 50 randomly selected patients presenting with back pain and radiculopathy. T2 inversion sequence was obtained in both axial and sagittal planes in addition to routine sequences. All the Magnetic Resonance Imaging (MRI) procedures were performed on 3T. One senior Musculoskeletal (MSK) radiologist, 2 general radiologists and a spinal surgeon blinded to final results reviewed images for the various disc pathologies individually analysing conventional and T2 inversion images. Data was analysed using Fischer's test and Chi2 test with a p value of <0.05 considered as significant.

RESULTS

Fifty randomly selected patients (mean age was 47.3 years(range 35-55 years) with back pain and radicular symptoms were included. The spectrum of disc pathologies included protrusions, annular fissures, discal cysts and calcified discs. Based on the above findings, T2 inversion sequence is not proved to be an alternative imaging sequence to routine MR imaging sequences for the depiction of various disc pathologies.

CONCLUSION

T2 inversion sequence does not increase the depiction of various lumbar disc pathologies in comparison with conventional sequences when used by experienced MSK radiologists. It may highlight abnormalities better for relatively inexperienced readers such as general radiologists and spinal surgeons.

Evaluation of the combined assessment of two digital enhancement filters in periapical radiographs obtained with different projection angles in the detection of simulated dental root fractures

OBJECTIVE

To evaluate the diagnostic efficacy of the combined assessment of the original radiographic image with the Invert or Emboss digital enhancement filters in periapical radiographs obtained with different horizontal projection angles in the detection of simulated dental root fracture.

MATERIALS AND METHODS

Thirty-four single-rooted teeth were selected, out of which 17 teeth were subjected to root fracture. Each tooth was individually placed in an empty socket of a dry human maxilla or mandible and X-rayed following the paralleling technique at three horizontal projections: mesial, right angle, distal. Then, the Invert and Emboss enhancement filters were applied. Five examiners independently evaluated all the images and rated the fractures using a 5-point scale. Weighted kappa test assessed the intra- and interexaminer agreements. Diagnostic values were calculated and the areas under the receiver operating characteristic curve (AUC) were compared using two-way ANOVA with Tukey test as post hoc (α = 0.05).

RESULTS

The inter- and intraexaminer agreement ranged from moderate to almost perfect and from substantial to almost perfect, respectively. Diagnostic values were considerably high for all conditions with no significant difference between the AUC values (p > 0.05).

CONCLUSIONS

The combined use of the original radiographic image with the Invert or Emboss digital enhancement filters in periapical radiographs obtained with different projection angles did not influence the detection of simulated dental root fracture.

Influence of the file format and transmission app on the radiographic diagnosis of caries lesions

OBJECTIVES

This in vitro study aimed to evaluate the influence of the radiographic image file format and the transmission application (app) on the diagnosis of proximal caries lesions.

STUDY DESIGN

Twenty bitewing radiographs of 40 posterior human teeth placed in phantoms were acquired using the Digora Toto digital sensor. All images were exported as TIFF (Tagged Image File Format), BMP (Windows Bitmap), PNG (Portable Network Graphics), and JPEG (Joint Photographic Experts Group) and transmitted online via WhatsApp and Messenger. Five examiners evaluated the radiographs with no online transmission and as transmitted through the 2 apps for the presence of proximal caries lesions using a 5-point scale. The reference standard for caries lesions was established using micro-computed tomography. Two-way analysis of variance compared values of sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve (α = .05). The kappa test was used to assess intra- and interexaminer agreement.

RESULTS

Sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve values showed no significant differences in the diagnosis of proximal caries lesions between the different image file formats (P ≥ .773) and transmission apps (P ≥ .608). Intraexaminer agreement was substantial (κ = 0.742) and interexaminer agreement was moderate (κ = 0.475).

CONCLUSION

The digital file format and transmission app did not influence the radiographic diagnosis of proximal caries lesions.

Is the digital radiographic detection of approximal caries lesions influenced by viewing conditions?

OBJECTIVES

The aim of this study was to assess the influence of different viewing conditions (combinations of computer display, horizontal viewing angle, and ambient lighting) on the detection of approximal caries lesions on digital radiographic images.

STUDY DESIGN

Forty posterior teeth were mounted in a plaster block and radiographed by using a CMOS sensor-based system. Three oral radiologists assessed the radiographic images under different conditions of computer display (iMac 5K 27", Barco MDRC-2124, and Dell P2314H), horizontal viewing angles (90 degrees, 67.5 degrees, and 45 degrees), and ambient lighting (low, medium, and high) and were asked to detect the presence of approximal caries lesions, which were confirmed by means of micro-computed tomography (micro-CT), using a 5-point scale. The area under the receiver operating characteristic curve, sensitivity, and specificity were calculated and compared by analysis of variance testing (α = 0.05). Intra- and interobserver agreements were assessed with the Kappa test.

RESULTS

Computer display, horizontal viewing angle, and ambient lighting did not significantly influence the diagnosis of approximal caries lesions. In general, moderate values of accuracy, low sensitivity, and high specificity were found for all viewing conditions.

CONCLUSIONS

The viewing conditions assessed in this study did not influence the detection of approximal caries lesions on digital radiographic images. Dental practitioners are encouraged to find their most comfortable viewing condition for this diagnostic task.

Can the Inversion Filter Improve the Visibility of the Mandibular Incisive Canal?

BACKGROUND

One of the anatomic structures in the mental interforaminal area is the mandibular incisive canal (MIC). Using various manipulation tools in the digital system may affect the visibility of MIC.

OBJECTIVES

The purpose of this study was to assess the effect of inversion filter (IF) on the visibility of mandibular incisive canal in panoramic radiographs.

PATIENTS AND METHODS

In this cross-sectional study, 2580 digital panoramic images of 18 to 70-year-old patients were inspected for presence of MIC. Visibility of MIC and extension of the canal were registered separately on each side using IF and conventional mode. Data were analyzed by Kappa test using SPSS version 20 software. A probability value of P < 0.05 was considered statistically significant.

RESULTS

There was no significant differences between IF and conventional mode regarding visibility of MIC (P > 0.05).

CONCLUSION

Although using IF caused improved visibility of MIC, the difference with conventional mode was not statistically different.