Ex vivoconfocal microscopy: a new diagnostic technique for mucormycosis

Role of VivaScope 2500 ex vivo confocal microscopy in skin pathology: Advantages, limitations, and future prospects

BACKGROUND

Vivascope 2500 ex vivo confocal microscopy (EVCM) is an emerging optical imaging device that allows nuclear level resolution of freshly excised tissues. EVCM provides, rapid real-time pathological examination in many subspecialties of pathology including skin, prostate, breast, liver, etc. In contrast to traditional time-consuming frozen sectioning and histological analysis.

AIMS

To evaluate the current state of EVCM utilization.

MATERIALS AND METHODS

This study highlights the advantages, limitations, and prospects of EVCM in skin pathology.

RESULTS

Our findings demonstrate that EVCM is a promising adjunctive tool to assess margins in Mohs surgery and to provide rapid, accurate diagnosis of cutaneous tumors, infectious and inflammatory diseases.

CONCLUSION

EVCM is a revolutionary device that can be used as an adjunct to paraffin-fixed, hematoxylin and eosin-stained slides and frozen sectioning. Additional refinements are required before EVCM can be used as an alternative to frozen sectioning or traditional tissue processing.

Applications of Reflectance Confocal Microscopy in the Diagnosis of Fungal Infections: A Systematic Review

Cutaneous and adnexal fungal infections are typically diagnosed with potassium hydroxide (KOH) skin scrapings, fungal cultures, and Periodic acid-Schiff (PAS) biopsy staining. All three current methods of fungal diagnosis require sample processing and turnover time which leads to a delay in diagnosis. Reflectance confocal microscopy (RCM) is a non-invasive, in vivo skin imaging technology that provides real-time dermatologic diagnoses. We present an updated systematic review of the applications of RCM in diagnosing fungal infections in an effort to explore the utility of RCM as an adjunct clinical tool in detecting cutaneous and adnexal fungi We systematically searched the MEDLINE (via PubMed) for studies published from January 2000 to October 2022 that described the utility of RCM in the setting of fungal infections. Of the 25 studies that met the inclusion criteria, 202 patients were included. The following information on the application of RCM in the setting of fungal infections was extracted from each study, if reported: study type, year published, number of patients included, diagnosis/diagnostic methods, and RCM description. Concordant within all included studies, fungal infections presented on RCM as bright, linear, branching, filamentous structures at the level of stratum corneum. A limitation of this review is that 11 of 25 studies were case reports (n = 1). Larger scale studies should be conducted to explore the utility of RCM in diagnosing fungal infections and to enrich the RCM descriptions of specific fungal conditions.

Simultaneous immunofluorescence and histology in pemphigus vulgaris using ex vivo confocal laser scanning microscopy

Ex vivo confocal laser scanning microscopy (ex vivo CLSM) provides rapid, high-resolution imaging and immunofluorescence examinations of the excised tissues. We aimed to evaluate the applicability of ex vivo CLSM in histomorphological and direct immunofluorescence (DIF) examination of pemphigus vulgaris (PV). 20 PV sections were stained with fluorescent-labeled anti-IgG and anti-C3 using various dilutions and incubation periods. Subsequently, the determined ideal staining protocol was applied on 20 additional PV and 20 control sections. Ex vivo CLSM identified intraepidermal blisters and acantholytic cells in 80% and 60% of PV patients, respectively. The sensitivity of ex vivo CLSM in detecting intraepidermal fluorescence was 90% both with IgG and C3. The specificity of staining for IgG and C3 was 70% and 90%, respectively. Histomorphological and immunofluorescence features of PV could be detected within the same ex vivo CSLM session showing a comparable performance to conventional histopathology and DIF microscopy.

Ex vivo confocal microscopy: revolution in fast pathology in dermatology

Confocal microscopy with in vivo and ex vivo modalities has been used in the evaluation of skin cancer and other dermatological disorders. Recent developments in ex vivo confocal microscopy allow for faster pathology assessment with greater accuracy by the visualization of cellular and architectural details, similarly to standard pathology, in either paraffin-embedded or frozen samples. They include the possibility of multimodal confocal microscopy using different lasers and fusion images. New staining protocols including immunostaining, with no damage to conventional histopathology preparation, have been recently described in melanocytic tumours and inflammatory skin diseases. Digital staining with haematoxylin and eosin is also incorporated in the new devices. In this review the applications of ex vivo confocal microscopy will be presented with the description of the technique and the technology, clinical evidence in dermatology and other fields, and further applications.

Ex vivo confocal laser scanning microscopy: An innovative method for direct immunofluorescence of cutaneous vasculitis

Ex vivo confocal laser scanning microscopy (ex vivo CLSM) offers an innovative diagnostic approach through vertical scanning of skin samples with a resolution close to conventional histology. In addition, it enables fluorescence detection in tissues. We aimed to assess the applicability of ex vivo CLSM in the detection of vascular immune complexes in cutaneous vasculitis and to compare its diagnostic accuracy with direct immunofluorescence (DIF) microscopy. Eighty-two sections of 49 vasculitis patients with relevant DIF microscopy findings were examined using ex vivo CLSM following staining with fluorescent-labeled IgG, IgM, IgA, C3 and fibrinogen antibodies. DIF microscopy showed immunoreactivity of vessels with IgG, IgM, IgA, C3 and Fibrinogen in 2.0%, 49.9%, 12.2%, 59.2% and 44.9% of the patients, respectively. Ex vivo CLSM detected positive vessels with the same antibodies in 2.0%, 38.8%, 8.2%, 42.9% and 36.7% of the patients, respectively. The detection rate of positive superficial dermal vessels was significantly higher in DIF microscopy as compared to ex vivo CLSM (P < .05). Whereas, ex vivo CLSM identified positive deep dermal vessels more frequently compared to DIF microscopy. In conclusion, ex vivo CLSM could identify specific binding of the antibodies in vessels and showed a comparable performance to conventional DIF microscopy in diagnosing vasculitis.

Ex vivo confocal microscopy: an emerging technique in dermatology

This review aims to give an overview of the current available applications of ex vivo confocal microscopy (EVCM) in dermatology. EVCM is a relatively new imaging technique that allows microscopic examination of freshly excised unfixed tissue. It enables a rapid examination of the skin sample directly in the surgery room and thus represents an alternative to the intraoperative micrographic control of the surgical margins of cutaneous tumors by standard microscopic examination on cryopreserved sections during Mohs surgery. Although this technique has mainly been developed for the margin’s control of basal cell carcinoma, many other skin tumors have been studied, including melanoma. Use of EVCM is continuing to evolve, and many possible applications are under investigation, such as the study of nails and hair diseases and the diagnosis of skin infections.

Ex vivo confocal microscopy features of cutaneous squamous cell carcinoma

BACKGROUND

Rapid microscopic evaluation of cutaneous squamous cell carcinoma (SCC), its grade of differentiation and level of invasiveness would enable better management of patients' therapy.

OBJECTIVES

Analyzing specific ex vivo confocal microscopy criteria whether they can predict diagnosis of invasive SCC vs carcinoma in situ and poorly differentiated or undifferentiated vs well and moderately differentiated SCC.

METHODS

Ex vivo confocal images of 102 SCCs in 57 patients were evaluated immediately after excision for the presence of predefined criteria based on confocal and histological knowledge.

RESULTS

In histopathological examination, 30 SCCs were in situ and 72 invasive. Of these, 29 invasive SCC tumors were well, 19 moderately, 15 poorly differentiated and 9 undifferentiated. χ² analysis demonstrated that presence of erosion/ulceration, plump bright or speckled cells in dermis, keratin pearls and peritumoral inflammatory infiltrate correlated with diagnosis of invasive SCC. Erosion/ulceration and peritumoral inflammatory infiltrate were observed more frequently in poorly differentiated or undifferentiated tumors. Plump bright or speckled cells in the dermis were observed less often in well-differentiated tumors. The presence of keratin pearls was associated with well or moderately differentiated tumors.

CONCLUSION

Ex vivo CLSM allowed rapid examination of SCC and provided useful information on invasiveness and grading of the tumor.

Immunofluorescence and confocal microscopy for ex-vivo diagnosis of melanocytic and non-melanocytic skin tumors: A pilot study

BACKGROUND

Ex-vivo confocal laser scanning microscopy (ex-vivo CLSM) offers rapid examination of freshly excised tissue. During the conventional examination immunohistochemistry enables to distinguish various cell types. The possibility of immunofluorescent techniques could enhance the accuracy of the diagnosis performed by ex-vivo CLSM.

METHODS

The tissue probes from various skin tumors were stained with FITC-labeled S-100A10, Melan-A and anti-Ber-EP4 antibodies before examination with ex-vivo CLSM in the fluorescence and reflectance modes. Results were compared to negative controls and conventional histopathology. The staining protocols were evaluated by establishing a scoring system according to the signal intensity found in ex-vivo CLSM.

RESULTS

S100 immunostaining was successful in 55.6%. Dilution of 1:200 resulted in the best possible evaluation of the tumor. The best suitable protocol was protocol B (phosphate buffered saline [PBS], without blocking agent). Melan A immunostaining was positive in 66.7%, the best dilution was 1:500 and protocol B (PBS, without blocking agent) was the most suitable. Ber-EP4 immunostaining presented a signal in 85.7%, the best dilutions were 1:200 and 1:500 and protocol A (PBS, with blocking agent) showed most optimal results.

CONCLUSION

The use of fluorescent-labeled antibodies in ex-vivo CLSM is possible and could improve intraoperative diagnostics of skin tumors.

[The role of reflectance confocal microscopy in the diagnosis of secondary syphilis of the vulva and anus: A first case report]

PATIENTS AND METHODS

Herein we report the case of an 18-year-old pregnant patient presenting with plantar and ano-genital lesions of syphilis, pharyngitis, erythematosus and scalynasolabial intertrigo and angular cheilitis.

REFLECTANCE CONFOCAL MICROSCOPY

In vivo reflectance confocal microscopy examination (Vivascope 3000^®; Caliber Inc, Rochester, NY, USA, distributed in France by Mavig, Munich) of ano-genital lesions enabled us to identify hyper-reflective elongated rods in the papillary dermis suggesting spirochetes. The diagnosis was confirmed by TPHA and VDRL as well as immunohistological examination.

COMMENTS

We identified for the first time rod shaped structures in ano-genital lesions of secondary syphilis, regularly alternating hyper-reflective and non-reflective areas corresponding to helix-shaped treponemes visualized by darkfield microscopy, which may not be confused with other cell structures.