Optical imaging guided- 'precision' biopsy of skin tumors: a novel approach for targeted sampling and histopathologic correlation.

Dermoscopy and reflectance confocal microscopy (RCM) are two noninvasive, optical imaging tools used to facilitate clinical diagnosis. A biopsy technique that produces exact correlation with optical imaging features is not previously reported. To evaluate the applications of a novel feature-focused 'precision biopsy' technique that correlates clinical-dermoscopy-RCM findings with histopathology. This was a prospective case-series performed during August 2017 and June 2019 at a tertiary care cancer. We included consecutive patients requiring a precise dermoscopy-RCM-histopathologic correlation. We performed prebiopsy dermoscopy and both wide probe and handheld RCM of suspicious lesions. Features of interest were isolated with the aid of paper rings and a 2 mm punch biopsy was performed in the dermoscopy- or RCM-highlighted area. Tissue was processed either en face or with vertical sections. One-to-one correlation with histopathology was obtained. Twenty-three patients with 24 lesions were included in the study. The mean age was 64.6 years (range 22-91 years); there were 16 (69.6%) males, 14 (58.3%) lesions biopsied were on head and neck region. We achieved tissue-conservation diagnosis in 100% (24/24), 13 (54.2%) were clinically equivocal lesions, six (25%) were selected for 'feature correlation' of structures on dermoscopy or RCM, and five (20.8%) for 'correlation of new/unknown' RCM features seen on follow-up. The precision biopsy technique described herein is a novel method that facilitates direct histopathological correlation of dermoscopy and RCM features. With the aids of optical imaging devices, accurate diagnosis may be achieved by minimally invasive tissue extraction.

Comparison of in situ cone beam computed tomography scan data with ex vivo optical scan data in the measurement of root surface area.

OBJECTIVE: The aim of this study was to compare root surface area (RSA) measurements of single-root teeth in a sheep mandible based on cone beam computed tomography (CBCT) with measurements made with an optical scanner. STUDY DESIGN: Eight anterior teeth of a sheep cadaver mandible were scanned in situ by using CBCT with 3 different exposure parameters, followed by treatment with smoothing software. The teeth were then extracted and scanned individually with an optical scanner. Three-dimensional digital models of the teeth were reconstructed on the basis of CBCT and optical scanner data. RSA data were calculated, and an equivalence test was used to statistically compare the measurements with significance of difference established at α = 0.05. RESULTS: The means of the differences between RSA measurements from CBCT and optical scanning ranged from 0.33% to 3.01%. There were no statistically significant differences between the 2 methods. The smoothing parameters for good fitness of the linear regression were determined to be 0.8 for the smooth factor, 8 for iterations, and 0 for compensate shrinkage. CONCLUSIONS: The proposed CBCT technique to measure RSA is feasible. RSA data obtained from CBCT in situ are as accurate as optical scanner measurements ex vivo.

Topical Aluminum Chloride and Monsel's Solution Block Toluidine Blue Staining in Mohs Frozen Sections: Mechanism and Solution.

BACKGROUND: A diminished-staining artifact is observed in some Mohs frozen sections that are stained in toluidine blue (T-blue). Such an artifact, not yet described in the literature, may interfere with a Mohs surgeon's accurate reading. The authors hypothesize that topical hemostatic agents, aluminum chloride, and Monsel's solution are the causative factors. OBJECTIVE: To evaluate the aforementioned topical hemostatic agents as a potential cause of the nonstaining artifact, to propose the mechanism associated with this phenomenon, and to develop a method to prevent or rectify the problem. MATERIALS AND METHODS: Leftover Mohs frozen sections and specimens were treated with aluminum chloride or Monsel's solution and processed with routine Mohs histology. RESULTS: Nonstaining artifact is reproduced in aluminum chloride or Monsel's solution-treated ex vivo skin specimens. The authors found that ethylenediaminetetraacetic acid (EDTA), a chelating agent, can reverse the staining blockage. Such a finding suggests that aluminum or ferric cations bind to tissue and subsequently inhibit T-blue from interacting with the tissue. Direct binding of ferric cations to the tissue section is demonstrated with Prussian blue iron staining. CONCLUSION: By rinsing Mohs frozen sections in an EDTA solution before T-blue staining, the authors could prevent hemostatic agent-induced nonstaining. Applying an EDTA wash and restaining the slides can correct the same artifact.

Mandibular inferior cortical bone thickness on panoramic radiographs in patients using bisphosphonates.

OBJECTIVE: The goal of this study was to detect dimensional changes in the mandibular cortical bone associated with bisphosphonate (BP) use and to correlate measurements of the cortical bone with the cumulative dose of BPs. STUDY DESIGN: Mandibular inferior cortical bone thickness (MICBT) was measured under the mental foramen on panoramic radiographs of patients with and without bisphosphonate-related osteonecrosis of the jaws (BRONJ) taking BPs and controls. RESULTS: Patients with BRONJ had the highest mean MICBT (6.81 ± 1.35 mm), compared with patients without BRONJ taking BPs (5.44 ± 1.09 mm) and controls (4.79 ± 0.85 mm) (P < .01). Mean MICBT of patients with BRONJ was significantly higher than that of patients without BRONJ taking BPs. There was a correlation between MICBT and cumulative dose of zolendronate. CONCLUSIONS: Measurement of MICBT on panoramic radiographs is a potentially useful tool for the detection of dimensional changes associated with BP therapy.

Mandibular cortical bone evaluation on cone beam computed tomography images of patients with bisphosphonate-related osteonecrosis of the jaw.

OBJECTIVES: The objective of this study was to develop a technique for detecting cortical bone dimensional changes in patients with bisphosphonate-related osteonecrosis of the jaw (BRONJ). STUDY DESIGN: Subjects with BRONJ who had cone-beam computed tomography imaging were selected, with age- and gender-matched controls. Mandibular cortical bone measurements to detect bisphosphonate-related cortical bone changes were made inferior to mental foramen, in 3 different ways: within a fixed sized rectangle, in a rectangle varying with the cortical height, and a ratio between area and height. RESULTS: Twelve BRONJ cases and 66 controls were evaluated. The cortical bone measurements were significantly higher in cases than controls for all 3 techniques. The bone measurements were strongly associated with BRONJ case status (odds ratio 3.36-7.84). The inter-rater reliability coefficients were high for all techniques (0.71-0.90). CONCLUSIONS: Mandibular cortical bone measurement is a potentially useful tool in the detection of bone dimensional changes caused by bisphosphonates.

Cell-based two-region competition algorithm with a map framework for boundary delineation of a series of 2D ultrasound images.

To ensure the delineated boundaries of a series of 2-D images closely following the visually perceivable edges with high boundary coherence between consecutive slices, a cell-based two-region competition algorithm based on a maximum a posteriori (MAP) framework is proposed. It deforms the region boundary in a cell-by-cell fashion through a cell-based two-region competition process. The cell-based deformation is guided by a cell-based MAP framework with a posterior function characterizing the distribution of the cell means in each region, the salience and shape complexity of the region boundary and the boundary coherence of the consecutive slices. The proposed algorithm has been validated using 10 series of breast sonograms, including seven compression series and three freehand series. The compression series contains two carcinoma and five fibroadenoma cases and the freehand series contains two carcinoma and one fibroadenoma cases. The results show that >70% of the derived boundaries fall within the span of the manually delineated boundaries. The robustness of the proposed algorithm to the variation of regions-of-interest is confirmed by the Friedman tests and the p-values of which are 0.517 and 0.352 for the compression and freehand series groups, respectively. The Pearson's correlations between the lesion sizes derived by the proposed algorithm and those defined by the average manually delineated boundaries are all higher than 0.990. The overlapping and difference ratios between the derived boundaries and the average manually delineated boundaries are mostly higher than 0.90 and lower than 0.13, respectively. For both series groups, all assessments conclude that the boundaries derived by the proposed algorithm be comparable to those delineated manually. Moreover, it is shown that the proposed algorithm is superior to the Chan and Vese level set method based on the paired-sample t-tests on the performance indices at a 5% significance level.

Cell-competition algorithm: a new segmentation algorithm for multiple objects with irregular boundaries in ultrasound images.

Segmentation of multiple objects with irregular contours and surrounding sporadic spots is a common practice in ultrasound image analysis. A new region-based approach, called cell-competition algorithm, is proposed for simultaneous segmentation of multiple objects in a sonogram. The algorithm is composed of two essential ideas. One is simultaneous cell-based deformation of regions and the other is cell competition. The cells are generated by two-pass watershed transformations. The cell-competition algorithm has been validated with 13 synthetic images of different contrast-to-noise ratios and 71 breast sonograms. Three assessments have been carried out and the results show that the boundaries derived by the cell-competition algorithm are reasonably comparable to those delineated manually. Moreover, the cell-competition algorithm is robust to the variation of regions-of-interest and a range of thresholds required for the second-pass watershed transformation. The proposed algorithm is also shown to be superior to the region-competition algorithm for both types of images.