Faculty Bibliography

BACKGROUND: Successful surgical management of primary hyperparathyroidism requires the ability to identify and distinguish normal from abnormal parathyroid tissue. Microscopic pathologic confirmation often helps with the diagnoses and decisions regarding the extent of parathyroid resection. Confocal reflectance microscopy (CRM) is an optical method of noninvasively imaging tissue without fixation, sectioning, and staining as in standard histopathology. The goal of this study was to determine if CRM imaging could be used to distinguish normal from diseased parathyroid tissue intraoperatively. METHODS: In this study, 44 parathyroid glands from 21 patients undergoing operations for primary hyperparathyroidism were imaged immediately after excision. CRM images were compared with conventional hematoxylin-and-eosin stained sections obtained from the same gland. The percentage area occupied by fat cells was calculated in images of both normal and diseased glands. RESULTS: Characteristic microscopic features of parathyroid glands were distinguishable by CRM and correlated well with histopathology. The stromal fat content of normal and diseased glands could easily be determined. The percentage area occupied by fat cells differed significantly (P <.00001) in normal glands (average, 23.0% +/- 10.9%) and adenomatous glands (average, 0.4% +/- 0.7%). CONCLUSIONS: CRM imaging rapidly revealed microscopic features that reliably differentiated normal and diseased parathyroid glands. The success of this preliminary ex vivo study promotes interest in further development of an in situ probe for in vivo clinical diagnostic use

BACKGROUND AND OBJECTIVES: It is difficult to deliver light uniformly and efficiently over the complex shapes presented by various organs for photodynamic therapy (PDT). A balloon delivery device for photodynamic therapy was designed and tested for treatment of various anatomic tissues. The device uses the principle of optical integration by multiple internal diffuse reflections to achieve uniform output illumination. STUDY DESIGN/MATERIALS AND METHODS: Soft, white, medical-grade silicone balloons were made in various shapes and tested for optical output, uniformity, efficiency, and power capabilities. Balloons were cast to be approximately the shape of the target tissue surface, organ, or cavity. Laser power was introduced into the saline-filled balloon by one or more fiber optics. Devices were constructed and used to illuminate oral mucosa and uterine endometrium for PDT. RESULTS: The balloon walls had low optical absorption, high diffuse reflectivity (80-95%), and low diffuse transmittance (5-20%) in the 500- to 900-nm wavelength region. Optical efficiencies of 65% were typical with emitted light over complex, nonspherical surfaces. Efficiency increased with inflation of the device, such that irradiance (power/area) at the balloon surface was nearly constant with inflation. CONCLUSION: Optically integrating balloons can provide highly uniform, efficient light exposure over complex tissue surfaces. Uniformity and irradiance were not strongly affected by balloon inflation, and these robust devices are easy to produce in essentially any shape

OBJECTIVES/HYPOTHESIS: To study the microscopic anatomy of normal oral tissues in vivo using confocal reflectance microscopy (CRM). This novel and noninvasive imaging modality can define and characterize healthy oral mucosa and thus this work serves as the foundation for studying oral diseases in vivo. STUDY DESIGN: This was a pilot observational cohort study comparing noninvasive CRM images with histology. MATERIALS AND METHODS: Lip and tongue mucosa were imaged by CRM in six healthy human subjects. In CRM living tissue is illuminated by a laser source and backscattered (or reflected) light is collected by a detector. Image contrast is determined by natural differences in refractive indices of organelles and other subcellular structures within the tissues. Gray-scale images were displayed in real-time on a video monitor and represented horizontal (en face) optical sections through the tissue. Motion of the oral tissue relative to the objective lens was minimized with a tissue stabilizer. After imaging, biopsies were taken from the same site of lip mucosa to correlate noninvasive confocal images with conventional histology. RESULTS: Confocal images correlated well with conventional histology, both qualitatively (visual analysis) and quantitatively (stereology). Imaging was possible up to depths of 490 and 250 microm in the lip and tongue, respectively. Cells and organelles including nuclei, circulating blood cells, and extracellular matrix were clearly observed. CONCLUSION: CRM provides details of normal human oral mucosa at the cellular level without the artifacts of histological processing, and thus has the potential for further development and use in clinical practice as a diagnostic tool for the early detection of oral cancer and precancer

BACKGROUND: Allergic contact dermatitis (ACD) is a common and often challenging clinical problem. In vivo near-infrared confocal reflectance microscopy (CM) is a new vital microscopy technique. OBJECTIVE: CM was used to evaluate acute ACD. METHODS: Patch testing by means of Finn Chambers technique was performed in 5 subjects to induce an acute allergic skin reaction. Noninvasive CM images from normal and eczematous skin were sequentially recorded before and after removal of the Finn Chambers. RESULTS: The epidermis and papillary dermis were clearly seen in high resolution. Retention of nuclei in stratum corneum, epidermal edema with microvesicle formation, and transepidermal migration of inflammatory cells were observed in vivo. Isolated dendritic cells were present in the ACD sites of 2 subjects, with morphology, size, and location consistent with Langerhans cells. Dermal vasodilation was observed as well. CONCLUSION: CM is a useful tool to study ACD and may be able to track Langerhans cell activation

Near-infrared confocal reflectance microscopy (CM) is a high-resolution: non-invasive imaging technique with promising future in dermatology. A pustular lesion from a 35-year-old male with a known history of folliculitis was non-invasively viewed with CM and later biopsied. Optical sections were correlated with routine histology. This optical technique allows us to view non-invasively transverse skin sections to a controlled depth in real time. In the CM images, tissue can be visualize with cellular and subcellular detail as shown by imaging infiltrating neutrophils (PMNs) within the subcorneal pustule of a superficial folliculitis in vivo

OBJECTIVES: To assess the potential of a near-infrared confocal laser scanning microscope (CLSM) for imaging bladder tissue in vivo. METHODS: Confocal images of the exposed bladder of male Sprague-Dawley rats were obtained with a CLSM. To minimize tissue motion, the bladder was placed in light contact under an objective lens housing, and the top surface was lightly flattened with a coverslip. Images were obtained from the outer and inner layers of the bladder wall with a lateral resolution of 0.5 to 1 microm and an axial resolution (section thickness) of 3 to 5 microm. The confocal images were later correlated with routine histologic studies. RESULTS: The CLSM allows imaging of the urothelium, the superficial and deep portions of the lamina propria, the muscularis propria, and the serosa of the bladder wall in vivo. Urothelial cells, collagen bundles and fibers, muscle, and circulating blood cells in capillaries and larger blood vessels are easily visualized. The confocal images correlated well with the histologic studies. CONCLUSIONS: Confocal microscopy allows real-time, high-resolution, high-contrast imaging of cellular and structural morphologic features to a maximal depth of 300 microm within the bladder wall in vivo. Artifacts caused by tissue motion can be minimized with a bladder-objective lens contact housing

BACKGROUND AND OBJECTIVE: This case demonstrates, for the first time, the use of in vivo confocal imaging to assess the efficacy of laser treatment of a skin lesion with a vascular component. STUDY DESIGN/PATIENT AND METHOD: A patient with lesions of sebaceous gland hyperplasia was histologically imaged in vivo before and after treatment with a 585 nm pulse dye laser (PDL) by using a near-infrared, confocal reflectance microscope. Hyperplastic sebaceous ducts and sebaceous glands were seen with high resolution in vivo. Prominent dermal vasculature was viewed as well as its selective targeting by PDL. CONCLUSION: Our results confirm the previously reported successful treatment of sebaceous gland hyperplasia with the 585 nm PDL