Shiny Structures Research Articles

Sphaeroptica: A tool for pseudo-3D visualization and 3D measurements on arthropods.

Natural history collections are invaluable reference collections. Digitizing these collections is a transformative process that improves the accessibility, preservation, and exploitation of specimens and associated data in the long term. Arthropods make up the majority of zoological collections. However, arthropods are small, have detailed color textures and share small, complex and shiny structures, which poses a challenge to conventional digitization methods. Sphaeroptica is a multi-images viewer that uses a sphere of oriented images. It allows the visualization of insects including their tiniest features, the positioning of landmarks, and the extraction of 3D coordinates for measuring linear distances or for use in geometric morphometrics analysis. The quantitative comparisons show that the measures obtained with Sphaeroptica are similar to the measurements derived from 3D μCT models with an average difference inferior to 1%, while featuring the high resolution of color stacked pictures with all details like setae, chaetae, scales, and other small and/or complex structures. Shaeroptica was developed for the digitization of small arthropods but it can be used with any sphere of aligned images resulting from the digitization of objects or specimens with complex surface and shining, black, or translucent texture which cannot easily be digitized using structured light scanner or Structure-from-Motion (SfM) photogrammetry.

Ultrasound segmentation analysis via distinct and completed anatomical borders

PurposeSegmenting ultrasound images is important for precise area and/or volume calculations, ensuring reliable diagnosis and effective treatment evaluation for diseases. Recently, many segmentation methods have been proposed and shown impressive performance. However, currently, there is no deeper understanding of how networks segment target regions or how they define the boundaries. In this paper, we present a new approach that analyzes ultrasound segmentation networks in terms of learned borders because border delimitation is challenging in ultrasound.MethodsWe propose a way to split the boundaries for ultrasound images into distinct and completed. By exploiting the Grad-CAM of the split borders, we analyze the areas each network pays attention to. Further, we calculate the ratio of correct predictions for distinct and completed borders. We conducted experiments on an in-house leg ultrasound dataset (LEG-3D-US) as well as on two additional public datasets of thyroid, nerves, and one private for prostate.ResultsQuantitatively, the networks exhibit around 10% improvement in handling completed borders compared to distinct borders. Similar to doctors, the network struggles to define the borders in less visible areas. Additionally, the Seg-Grad-CAM analysis underscores how completion uses distinct borders and landmarks, while distinct focuses mainly on the shiny structures. We also observe variations depending on the attention mechanism of each architecture.ConclusionIn this work, we highlight the importance of studying ultrasound borders differently than other modalities such as MRI or CT. We split the borders into distinct and completed, similar to clinicians, and show the quality of the network-learned information for these two types of borders. Additionally, we open-source a 3D leg ultrasound dataset to the community https://github.com/Al3xand1a/segmentation-border-analysis.

Pink plaque on the hypogastrium

Bowen’s disease is a type of intraepidermal squamous cell carcinoma usually affecting the elderly and occurring on sun-exposed areas, such as the face, scalp, and limbs. The development of Bowen’s disease in other locations such as the abdomen is rare. In these cases, dermoscopy proves to be a helpful tool in making the diagnosis [1]. A 65-year-old male with no previous medical history presented himself with a nonhealing asymptomatic lesion on the abdomen slowly growing for the last ten years. A dermatological examination revealed a 6-cm well-limited erythematous plaque on the hypogastrium with peripheral pigmentation (Fig. 1). Dermoscopy found central keratin as well as white shiny structures, including white shiny lines, white shiny areas, and rosettes (Fig. 2) as well as brown linear globules and dots on the periphery and looped vessels (Fig. 3). Bowen’s disease was the most likely diagnosis, which was confirmed by histopathology. The patient underwent surgery for excision of the lesion with 5-mm margins.

Dermoscopy as a Tool for Estimating Breslow Thickness in Melanoma

Background and objectiveThe incidence of melanoma has increased significantly, and early diagnosis is the most effective way to reduce associated deaths. Dermoscopy increases diagnostic accuracy in melanoma and analysis of dermoscopic structures can help in the estimation of tumor thickness. The aim of this study was to analyze the influence of Breslow thickness on the dermoscopic characteristics of melanoma. Material and methodsObservational, cross-sectional study of patients with histologically confirmed melanoma and dermoscopic images of the tumor. The patients were divided into 3 groups: melanoma in situ, thin melanoma (≥ 1 mm Breslow thickness), and thick melanoma (≥ 1 mm Breslow thickness). Age, sex, tumor location, and histologic and dermoscopic characteristics were analyzed in all cases. ResultsWe studied 215 patients: 88 with melanoma in situ, 73 with thin melanoma, and 54 with thick melanoma. The frequency of the following dermoscopic features increased with increasing Breslow thickness: the blue-white veil (P < .001), white shiny structures (P < .001), and milky-red areas (P < .003). Angulated lines, by contrast, became less common with increasing thickness (P < .002). ConclusionsDermoscopy not only improves diagnostic accuracy for pigmented lesions but also helps in the preoperative assessment of Breslow thickness in melanoma.

La dermatoscopia como herramienta para inferir el Breslow del melanoma

Background and objectiveThe incidence of melanoma has increased significantly, and early diagnosis is the most effective way to reduce associated deaths. Dermoscopy increases diagnostic accuracy in melanoma and analysis of dermoscopic structures can help in the estimation of tumor thickness. The aim of this study was to analyze the influence of Breslow thickness on the dermoscopic characteristics of melanoma. Material and methodsObservational, cross-sectional study of patients with histologically confirmed melanoma and dermoscopic images of the tumor. The patients were divided into three groups: melanoma in situ, thin melanoma (≥ 1 mm Breslow thickness), and thick melanoma (≥ 1 mm Breslow thickness). Age, sex, tumor location, and histologic and dermoscopic characteristics were analyzed in all cases. ResultsWe studied 215 patients: 88 with melanoma in situ, 73 with thin melanoma, and 54 with thick melanoma. The frequency of the following dermoscopic features increased with increasing Breslow thickness: the blue-white veil (p < 0.001), white shiny structures (p < 0.001), and milky-red areas (p < 0.003). Angulated lines, by contrast, became less common with increasing thickness (p < 0.002). ConclusionsDermoscopy not only improves diagnostic accuracy for pigmented lesions but also helps in the preoperative assessment of Breslow thickness in melanoma.

Dermoscopy of a Squamous Cell Carcinoma of the Lower Lip Showing Multiple Rosettes.

The term white shiny structures groups 3 well-defined morphologies including white shiny lines, white shiny areas, and rosettes. They all can be observed exclusively with polarized light dermoscopy. Rosettes are defined as 4 bright white circles arranged as a square resembling a 4-leaf clover, mainly localized in the follicular openings. Despite being well-described dermoscopically, their exact histology correlation is uncertain. The presence of white rosettes is suggestive of a diagnosis of actinic keratosis or squamous cell carcinoma (SCC), but they also can be seen in a range of skin conditions and in nonlesional photo-damaged skin [1]. SCC of the lip represents 20% of all oral carcinomas; its dermoscopic criteria were recently described, with the main dermoscopic features being the presence of ulceration, scales, polymorphous vessels, and white structures such as white structureless areas, white shiny lines, white circles, and perivascular white halos [2]. Herein we report a case showing multiple rosettes on an SCC of the lower lip.

Dermoscopic features of digital mucous cysts: A study of 23 cases.

Digital mucous cysts (DMC) are common benign myxoid cysts typically located on the fingers and toes. Recently, dermoscopic patterns of DMC were reported. However, only a small number of cases were described in the published work; therefore, information on this topic is scarce in the published work. We investigated dermoscopic patterns of histopathologically diagnosed DMC. In total, 23 cases were enrolled in this study. Polarized dermoscopy revealed vascular patterns in 13 cases (56.5%), with arborizing vascular patterns, dotted vessels, linear vessels and polymorphous vessels in eight (34.8%), three (13.0%), one (4.3%) and one (4.3%) case, respectively. Red-purple lacunas, ulceration, nail dystrophy and white shiny structures were detected in five (21.7%), two (8.7%), seven (30.4%) and six cases (26.1%), respectively. We report the largest case series regarding dermoscopic features of DMC to date. Dermoscopy can be used as a helpful adjuvant and non-invasive tool in the diagnosis of DMC.

Rosettes and other white shiny structures in polarized dermoscopy: histological correlate and optical explanation

Rosettes are a specific form of a white shiny structure seen with polarized dermoscopy. The precise morphological correlate and optical explication are not known. To estimate the frequency of rosettes in ex vivo dermoscopy and to find explication and morphologic correlate of this dermoscopic feature. A series of 6108 consecutive skin biopsies were examined with ex vivo dermoscopy and when rosettes were present serial transverse sections with polarization were examined. In this series of 6108 consecutive skin biopsies, rosettes were found on ex vivo dermoscopy in 63 cases. When multiple we observed that they are always oriented at the same angle. Transverse sections with polarization of these lesions proved that smaller rosettes are mainly caused by polarizing horny material in adnexal openings, and larger rosettes by concentric perifollicular fibrosis. Rosettes are an optical effect of crossed polarization by concentric fibrosis or horny material and hence are not lesion-specific.

Dermoscopic Findings for the Early Detection of Melanoma: An Analysis of 200 Cases

IntroductionDermoscopy is a complementary technique that has led to major advances in the diagnosis of pigmented skin lesions. The aim of this study was to describe the dermoscopic features of a series of melanomas and analyze the differences between melanomas in situ and invasive melanomas. Material and methodsWe retrospectively recorded epidemiological, clinical, histologic, and dermoscopic features of a series of 200 primary melanomas. We performed a descriptive and analytical study of the dermoscopic features identified. ResultsThe mean age of the patients was 63 years and there was a similar distribution of male and female patients. The most common histologic subtypes were superficial spreading melanoma (62.5%) and lentigo maligna (25.5%); 67% of the melanomas had a Breslow thickness of less than 1mm and 24.5% were melanomas in situ. Overall,the most common global dermoscopic features were the multicomponent pattern (33.5%), the reticular pattern (18%), and the nonspecific pattern (15.5%). The most common local features were structureless homogeneous areas (67.5%), white-blue structures (58%), an atypical pigmented network (55.5%), and irregularly distributed dots and globules (44%). The following features were more common in invasive melanomas than in melanomas in situ: blue, gray, red and white colors, multicomponent and homogeneous patterns, dots and globules, blue-white structures, homogeneous areas, a blue-white veil, white shiny structures, a reverse pigment network, and milky-red areas. The reticular pattern was more common in melanomas in situ. DiscussionThe use of dermoscopy has contributed to the early diagnosis of melanoma. The most common dermoscopic features of melanoma are multiple structures and colors (multicomponent pattern), an atypical reticular pattern (with wide, irregular meshes), and an absence of distinguishing features (nonspecific pattern) associated with the presence of vascular structures. ConclusionsDermoscopy facilitates the diagnosis of melanoma and could be useful for differentiating between melanoma in situ and invasive melanoma.

Hallazgos dermoscópicos para la detección precoz del melanoma. Análisis de 200 casos

IntroductionDermoscopy is a complementary technique that has led to major advances in the diagnosis of pigmented skin lesions. The aim of this study was to describe the dermoscopic features of a series of melanomas and analyze the differences between melanomas in situ and invasive melanomas. Material and methodsWe retrospectively recorded epidemiological, clinical, histologic, and dermoscopic features of a series of 200 primary melanomas. We performed a descriptive and analytical study of the dermoscopic features identified. ResultsThe mean age of the patients was 63 years and there was a similar distribution of male and female patients. The most common histologic subtypes were superficial spreading melanoma (62.5%) and lentigo maligna (25.5%); 67% of the melanomas had a Breslow thickness of less than 1mm and 24.5% were melanomas in situ. Overall,the most common global dermoscopic features were the multicomponent pattern (33.5%), the reticular pattern (18%), and the nonspecific pattern (15.5%). The most common local features were structureless homogeneous areas (67.5%), white-blue structures (58%), an atypical pigmented network (55.5%), and irregularly distributed dots and globules (44%). The following features were more common in invasive melanomas than in melanomas in situ: blue, gray, red and white colors, multicomponent and homogeneous patterns, dots and globules, blue-white structures, homogeneous areas, a blue-white veil, white shiny structures, a reverse pigment network, and milky-red areas. The reticular pattern was more common in melanomas in situ. DiscussionThe use of dermoscopy has contributed to the early diagnosis of melanoma. The most common dermoscopic features of melanoma are multiple structures and colors (multicomponent pattern), an atypical reticular pattern (with wide, irregular meshes), and an absence of distinguishing features (nonspecific pattern) associated with the presence of vascular structures. ConclusionsDermoscopy facilitates the diagnosis of melanoma and could be useful for differentiating between melanoma in situ and invasive melanoma.

White Shiny Structures in Melanoma and BCC

W HITE SHINY STRUCTURES SEEN UNDER polarized dermoscopy take on 3 distinct morphological appearances. One category includes white shiny lines, which are often orthogonally oriented. This structure also has a metaphoric name known as chrysalis, although some authors believe that chrysalis is a misnomer and prefer that it be replaced with the term crystalline. (We are in agreement with this opinion.) White shiny areas, also known as white shiny clods, appear as larger structureless areas of shiny white color. Finally, rosettes (also a metaphoric term) appear as 4 shiny white points arranged in a pattern reminiscent of a 4-leaf clover. Although both white shiny lines and white shiny areas have been observed in basal cell carcinoma (BCC) and melanoma, the prevalence of these structures seems to differ between these 2 malignant neoplasms. In BCC, we have noticed that it is common to see both white shiny lines (112 of 162 cases [69.1%]) and white shiny areas (39 of 162 cases [24.1%]). In contrast, although we have observed that crystalline structures are prevalent in melanoma (71 of 249 cases [28.5%]), white shiny areas are seen only rarely (8 of 249 cases [3.2%]) (unpublished observation, October 2010). Herein, we show intensely white, widespread, haphazard white shiny lines (Figure, A and C, white arrows) and white shiny areas (Figure, A and C, black arrows) in a superficial BCC (Figure, A and B) and a nodular BCC (Figure, C) under polarized dermoscopy. These structures cannot be seen in the nonpolarized dermoscopic image (Figure, B). We also show white shiny lines in an in situ and invasive melanoma (Figure, D, arrows) and a melanoma metastasis (Figure, E, arrows).

Dermoscopic Features of Basal Cell Carcinomas: Differences in Appearance Under Non-Polarized and Polarized Light

Basal cell carcinomas (BCCs) can be diagnosed using different dermoscopic modalities. To evaluate dermoscopic features of BCCs using nonpolarized and polarized dermoscopy to highlight similarities and differences between dermoscopic modalities. Retrospective study of 149 BCCs under nonpolarized dermoscopy (NPD), polarized contact dermoscopy (PCD), and polarized noncontact dermoscopy (PNCD). Images were evaluated for a range of dermoscopic colors, structures, and vessels. Features were compared according to histopathologic subtype. The most common dermoscopic structures in BCCs across all modalities included globules (50.3-51.0%), dots (49.7-50.3%), white structureless areas (63.1-74.5%), structureless gray-brown areas (24.2-24.8%), and ulcerations (28.2%). The most frequently observed vasculature included arborizing vessels (18.8-38.3%), short fine telangiectasias (SFTs) (73.8-82.6%), and vascular blush (41.6-83.2%). Structures with higher levels of agreement across modalities included pigmented structures and ulcerations. Lower levels of agreement existed between contact and noncontact modalities for certain vascular features. White shiny structures, which include shiny white lines (chrysalis and crystalline structures) (0-69.1%), shiny white areas (0-25.5%), and rosettes (0-11.4%), exhibited no agreement between NPD and polarized modalities. This study highlights differences in dermoscopic features of BCCs under three dermoscopic modalities. Shiny white lines (chrysalis and crystalline structures) and shiny white areas may be used as additional criteria to diagnose BCCs.

White shiny structures: dermoscopic features revealed under polarized light

White shiny structures, including white shiny lines, white shiny areas and rosettes, are features only observed under polarized dermoscopy (PD). To evaluate the prevalence of the varied morphologies of white shiny structures in melanoma, basal cell carcinoma (BCC), squamous cell carcinoma (SCC), actinic keratosis (AK) and lichen planus-like keratosis (LPLK). Retrospective study using dermoscopic images of biopsy-proven melanoma, BCC, SCC, AK and LPLK. A total of 538 lesions were assessed under PD. One or more types of white shiny structures were observed in 38.7% of study lesions (208/538). BCCs were significantly more likely to display a combination of white shiny areas and white shiny lines (short lines and/or ill-defined strands) (31.9%; 61/191) than any other lesions (P<0.001). BCC were more likely than other lesions to have white shiny lines distributed without any organized pattern (P<0.001). Lines in melanoma were significantly more likely than other lesion types to be oriented orthogonally (P<0.001). When white shiny lines were present, melanomas were significantly more likely than other lesions to exhibit short discrete white lines (P<0.001). Rosettes were significantly more likely to be observed in actinic tumours than other lesions (P<0.001). The presence of white shiny lines of any length accompanied by white shiny areas is most suggestive of a diagnosis of BCC (P<0.001). Melanomas are more likely to display short white shiny lines in an orthogonal distribution (P<0.001) and without white shiny areas. Actinic tumours are most likely to exhibit rosettes (P<0.001).