Super‐high magnification dermoscopy can add information for the differential diagnosis between melanoma and atypical nevi

Background: Differential diagnosis of clinically atypical nevi (aN) and early melanomas (eMM) still represents a challenge even for experienced dermoscopists, as dermoscopy alone is not sufficient to adequately differentiate these equivocal melanocytic skin lesions (MSLs). Objectives: The objectives of this study were to investigate what were the most relevant parameters for noninvasive differential diagnosis between eMM and aN among clinical, personal, and dermoscopic data and to evaluate their impact as risk factors for malignancy. Methods: This was a retrospective study performed on 450 MSLs excised from 2014 to 2016 with a suspicion of malignancy. Dermoscopic standardized images of the 450 MSLs (300 aN and 150 eMM) were collected and evaluated. Patients’ personal data (ie, age, gender, body site, maximum diameter) were also recorded. Dermoscopic evaluations were performed by 5 different experts in dermoscopy blinded to histopathological diagnosis. Fleiss’ κ was calculated to measure concordance level between experts in the description of dermoscopic parameters for each MSL. The power of the studied variables in discriminating malignant from benign lesions was also investigated through F-statistics. Results: The variables age and maximum diameter supplied the highest discriminant power (F = 253 and 227, respectively). Atypical network, blue white veil and white shiny streaks were the most significant dermoscopic patterns suggestive of malignancy (F = 110, 104 and 99.5, respectively). Shiny white streaks was the only dermoscopic parameter to obtain satisfactory concordance value. Gender was not a discriminant factor. The specific statistical weight of clinical and personal data (ie, “patient’s age” and “lesion diameter”) surpassed those of atypical dermoscopic features. Conclusions: The objective clinical and personal data collected here could supply a fundamental contribution in the correct diagnosis of equivocal MSLs and should be included in diagnostic algorithms along with significant dermoscopic features (ie, atypical network, blue-white veil, and shiny white streaks)

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The Microstructure of Shock-Synthesized Diamond

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010006163x ◽

1967 ◽

Vol 25 ◽

pp. 324-325

Author(s):

Lucien F. Trueb

Keyword(s):

Single Crystals ◽

Preferred Orientation ◽

High Magnification ◽

Texture Pattern ◽

Shock Process ◽

New Type ◽

Diffraction Diagram

A new type of synthetic industrial diamond formed by an explosive shock process has been recently developed by the Du Pont Company. This material consists of a mixture of two basically different forms, as shown in Figure 1: relatively flat and compact aggregates of acicular crystallites, and single crystals in the form of irregular polyhedra with straight edges.Figure 2 is a high magnification micrograph typical for the fibrous aggregates; it shows that they are composed of bundles of crystallites 0.05-0.3 μ long and 0.02 μ. wide. The selected area diffraction diagram (insert in Figure 2) consists of a weak polycrystalline ring pattern and a strong texture pattern with arc reflections. The latter results from crystals having preferred orientation, which shows that in a given particle most fibrils have a similar orientation.

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Tumor Diagnosis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053966 ◽

1982 ◽

Vol 40 ◽

pp. 262-265

Author(s):

Bruce Mackay

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Differential Diagnosis ◽

Light Microscopy ◽

Clinical Examination ◽

Ultrastructural Study ◽

Diagnostic Procedures ◽

Specific Diagnosis ◽

Transmission Electron ◽

Microscopic Diagnosis

The broadest application of transmission electron microscopy (EM) in diagnostic medicine is the identification of tumors that cannot be classified by routine light microscopy. EM is useful in the evaluation of approximately 10% of human neoplasms, but the extent of its contribution varies considerably. It may provide a specific diagnosis that can not be reached by other means, but in contrast, the information obtained from ultrastructural study of some 10% of tumors does not significantly add to that available from light microscopy. Most cases fall somewhere between these two extremes: EM may correct a light microscopic diagnosis, or serve to narrow a differential diagnosis by excluding some of the possibilities considered by light microscopy. It is particularly important to correlate the EM findings with data from light microscopy, clinical examination, and other diagnostic procedures.

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Macromolecular structures of biological specimens are not obscured by controlled osmium impregnation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100076639 ◽

1983 ◽

Vol 41 ◽

pp. 606-607

Author(s):

Klaus-Ruediger Peters ◽

Samuel A. Green

Keyword(s):

Thin Films ◽

Electrical Conductivity ◽

Critical Point ◽

Metal Films ◽

High Magnification ◽

Osmium Impregnation ◽

Instrumental Resolution ◽

20 Nm ◽

Continuous Metal

High magnification imaging of macromolecules on metal coated biological specimens is limited only by wet preparation procedures since recently obtained instrumental resolution allows visualization of topographic structures as smal l as 1-2 nm. Details of such dimensions may be visualized if continuous metal films with a thickness of 2 nm or less are applied. Such thin films give sufficient contrast in TEM as well as in SEM (SE-I image mode). The requisite increase in electrical conductivity for SEM of biological specimens is achieved through the use of ligand mediated wet osmiuum impregnation of the specimen before critical point (CP) drying. A commonly used ligand is thiocarbohvdrazide (TCH), first introduced to TEM for en block staining of lipids and glvcomacromolecules with osmium black. Now TCH is also used for SEM. However, after ligand mediated osinification nonspecific osmium black precipitates were often found obscuring surface details with large diffuse aggregates or with dense particular deposits, 2-20 nm in size. Thus, only low magnification work was considered possible after TCH appl ication.

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SEM Examination of a Used Diamond Knife

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100066310 ◽

1971 ◽

Vol 29 ◽

pp. 452-453

Author(s):

J. Temple Black

Keyword(s):

Electron Microscope ◽

High Voltage ◽

High Magnification ◽

Metallic Materials ◽

Wide Spread ◽

Thin Sections ◽

Transmission Electron ◽

Scanning Transmission ◽

Scanning Electron ◽

Diamond Knife

Since its introduction by Fernandez-Moran, the diamond knife has gained wide spread usage as a common material for cutting of thin sections of biological and metallic materials into thin films for examination in the transmission electron microscope. With the development of high voltage E.M. and scanning transmission E.M., microtomy applications will become increasingly important in the preparation of specimens. For those who can afford it, the diamond knife will thus continue to be an important tool to accomplish this effort until a cheaper but equally strong and sharp tool is found to replace the diamond, glass not withstanding.In Figs. 1 thru 3, a first attempt was made to examine the edge of a used (β=45°) diamond knife by means of the scanning electron microscope. Because diamond is conductive, first examination was tried without any coating of the diamond. However, the contamination at the edge caused severe charging during imaging. Next, a thin layer of carbon was deposited but charging was still extensive at high magnification - high voltage settings. Finally, the knife was given a light coating of gold-palladium which eliminated the charging and allowed high magnification micrographs to be made with reasonable resolution.

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Analysis of the Anterior Secretory Cells of Onchidohs Muricata (Nudibranchia)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100099490 ◽

1981 ◽

Vol 39 ◽

pp. 614-615

Author(s):

Roy Skidmore

Keyword(s):

Endoplasmic Reticulum ◽

Secretory Granules ◽

Golgi Body ◽

The Body ◽

Secretory Cells ◽

Secretory Vesicles ◽

High Magnification ◽

Large Numbers ◽

Membrane Bound ◽

Sole Of The Foot

The long-necked secretory cells in Onchidoris muricata are distributed in the anterior sole of the foot. These cells are interspersed among ciliated columnar and conical cells as well as short-necked secretory gland cells. The long-necked cells contribute a significant amount of mucoid materials to the slime on which the nudibranch travels. The body of these cells is found in the subepidermal tissues. A long process extends across the basal lamina and in between cells of the epidermis to the surface of the foot. The secretory granules travel along the process and their contents are expelled by exocytosis at the foot surface.The contents of the cell body include the nucleus, some endoplasmic reticulum, and an extensive Golgi body with large numbers of secretory vesicles (Fig. 1). The secretory vesicles are membrane bound and contain a fibrillar matrix. At high magnification the similarity of the contents in the Golgi saccules and the secretory vesicles becomes apparent (Fig. 2).

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The Preschool Stuttering Screen for Health Care Professionals

Perspectives on Fluency and Fluency Disorders ◽

10.1044/ffd21.2.59 ◽

2011 ◽

Vol 21 (2) ◽

pp. 59-62

Author(s):

Joseph Donaher ◽

Christina Deery ◽

Sarah Vogel

Keyword(s):

Risk Factors ◽

Health Care ◽

Differential Diagnosis ◽

Preschool Children ◽

Health Care Professionals ◽

Healthcare Professionals ◽

Evidence Based ◽

Developmental Profile

Healthcare professionals require a thorough understanding of stuttering since they frequently play an important role in the identification and differential diagnosis of stuttering for preschool children. This paper introduces The Preschool Stuttering Screen for Healthcare Professionals (PSSHP) which highlights risk factors identified in the literature as being associated with persistent stuttering. By integrating the results of the checklist with a child’s developmental profile, healthcare professionals can make better-informed, evidence-based decisions for their patients.

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Auditory Threshold Consistency in Differential Diagnosis of Aphasia in Children

Journal of Speech and Hearing Disorders ◽

10.1044/jshd.2902.147 ◽

1964 ◽

Vol 29 (2) ◽

pp. 147-155 ◽

Cited By ~ 7

Author(s):

Jerome Reichstein

Keyword(s):

Differential Diagnosis ◽

Auditory Threshold

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The Effect of Sensori-Neural Hearing Loss on Threshold-Duration Functions

Journal of Speech and Hearing Research ◽

10.1044/jshr.1104.842 ◽

1968 ◽

Vol 11 (4) ◽

pp. 842-852 ◽

Cited By ~ 26

Author(s):

H. N. Wright

Keyword(s):

Hearing Loss ◽

Differential Diagnosis ◽

Time Constant ◽

Present Series ◽

Auditory Disorders ◽

Threshold Duration

Previous findings on the threshold for tones as a function of their duration have suggested that such functions may be systematically affected by sensori-neural hearing losses of cochlear origin. The present series of investigations was designed to explore this relation further and to determine also whether the amount of hearing loss present has any effect upon the results which are obtained. Preliminary studies were also carried out on a conductively impaired listener to indicate whether hearing losses of this type affect the threshold-duration function. The results indicate that the threshold-duration function is systematically affected by sensori-neural hearing losses of cochlear origin. This effect is manifested by a progressive shortening of the time constant relating threshold to duration and is not uniquely related to the amount of hearing loss present. The results obtained from the conductively impaired listener suggested that this type of hearing loss has no effect on the threshold-duration function, thereby implying that such functions may contribute significantly to the differential diagnosis of auditory disorders.

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