Rapid and Label-Free Histopathology of Oral Lesions Using Deep Learning Applied to Optical and Infrared Spectroscopic Imaging Data.

Oral potentially malignant disorders (OPMDs) are precursors to over 80% of oral cancers. Hematoxylin and eosin (H&E) staining, followed by pathologist interpretation of tissue and cellular morphology, is the current gold standard for diagnosis. However, this method is qualitative, can result in errors during the multi-step diagnostic process, and results may have significant inter-observer variability. Chemical imaging (CI) offers a promising alternative, wherein label-free imaging is used to record both the morphology and the composition of tissue and artificial intelligence (AI) is used to objectively assign histologic information. Here, we employ quantum cascade laser (QCL)-based discrete frequency infrared (DFIR) chemical imaging to record data from oral tissues. In this proof-of-concept study, we focused on achieving tissue segmentation into three classes (connective tissue, dysplastic epithelium, and normal epithelium) using a convolutional neural network (CNN) applied to three bands of label-free DFIR data with paired darkfield visible imaging. Using pathologist-annotated H&E images as the ground truth, we demonstrate results that are 94.5% accurate with the ground truth using combined information from IR and darkfield microscopy in a deep learning framework. This chemical-imaging-based workflow for OPMD classification has the potential to enhance the efficiency and accuracy of clinical oral precancer diagnosis.

Infrared spectroscopic laser scanning confocal microscopy for whole-slide chemical imaging.

Chemical imaging, especially mid-infrared spectroscopic microscopy, enables label-free biomedical analyses while achieving expansive molecular sensitivity. However, its slow speed and poor image quality impede widespread adoption. We present a microscope that provides high-throughput recording, low noise, and high spatial resolution where the bottom-up design of its optical train facilitates dual-axis galvo laser scanning of a diffraction-limited focal point over large areas using custom, compound, infinity-corrected refractive objectives. We demonstrate whole-slide, speckle-free imaging in ~3 min per discrete wavelength at 10× magnification (2 µm/pixel) and high-resolution capability with its 20× counterpart (1 µm/pixel), both offering spatial quality at theoretical limits while maintaining high signal-to-noise ratios (>100:1). The data quality enables applications of modern machine learning and capabilities not previously feasible - 3D reconstructions using serial sections, comprehensive assessments of whole model organisms, and histological assessments of disease in time comparable to clinical workflows. Distinct from conventional approaches that focus on morphological investigations or immunostaining techniques, this development makes label-free imaging of minimally processed tissue practical.

Metal Hypersensitivity and Complex Regional Pain Syndrome After Bilateral Total Knee Arthroplasty: A Case Report.

CASE: A 38-year-old man underwent bilateral total knee arthroplasty (TKA) and subsequently developed diffuse pain, swelling, and an eczematous rash that spread throughout his body. Despite various pharmacological regimens, sympathetic blocks, aggressive physical therapy, and further knee revisions, the patient's symptoms progressed over a period of 2 years. An in vitro memory lymphocyte immuno-stimulation assay test demonstrated reactivity to nickel after which bilateral revision TKAs with oxidized zirconium alloys resulted in symptomatic improvement. CONCLUSION: Metal hypersensitivity should be considered after the exclusion of infection; however, the concurrent development of complex regional pain syndrome may mask the clinical presentation.

Iodine-125 radioactive seed brachytherapy as a treatment for spine and bone metastases: A systematic review and meta-analysis.

AIM: To evaluate the analgesic efficacy, safety, and local tumor control of iodine-125 (125I) seed brachytherapy (BT) for the management of spine and bone metastases. METHODS: A systematic literature search was conducted using PubMed, the Cochrane Library, and Scopus databases. Data regarding patient demographics, tumor characteristics, procedural parameters, and clinical outcomes were extracted and analyzed. RESULTS: Fourteen studies (7 prospective, 7 retrospective) were included, accounting for 689 patients, in our review. Analgesic efficacy was assessed at baseline and various postoperative time points. Significant improvement in pain was noted at 4- and 24-week follow-ups (p < 0.01). Interestingly, all studies that combined 125I seed BT with cement augmentation reported relatively higher levels of pain reduction (mean pain reduction ≥4 points) as compared to the studies which applied 125I seed BT as a stand-alone therapy (mean pain reduction ≥2 points), at the last follow-up. Local tumor control rates ranged widely from 14% to 100% at varying follow-ups. Median overall survival ranged between 10 months and 25 months. The overall complication rate was 19% (130/689) and mainly included minor subcutaneous hemorrhage, fever, myelosuppression, and seed displacement. Metrics assessing performance and quality of life demonstrated significant improvements from baseline to posttreatment. CONCLUSION: 125I seed BT, alone or in conjunction with cement augmentation, may be a viable salvage therapy in appropriately selected patients. However, further studies are needed to analyze the long-term efficacy of this intervention as a palliative and curative modality.

Lumbar Facet Joint Cyst Treated With Decompression and Interlaminar Stabilization.

Spinal facet joint cysts (FJCs) are an increasingly reported cause of lower back pain, radiculopathy, and neurological deficits owing to their proximity to adjacent nerve roots. The etiology of these cysts has not yet been fully elucidated, although they appear to be related to degenerative changes in the facet joints themselves. Conservative management strategies including physical therapy and oral analgesics rarely result in spontaneous regression of an FJC, often providing only short-term relief. The current treatment modalities reported for FJCs generally range from percutaneous cyst aspiration to decompression surgery with or without instrumented spinal fusion. However, instrumented fusion often results in a higher rate of complications such as pseudoarthrosis and adjacent segment disease. The Coflex® (Paradigm Spine, LLC, New York, NY) interlaminar stabilization (ILS) implant is a novel titanium, U-shaped device which acts as a motion-preserving stabilizer and has proven to be a viable alternative to instrumental fusion. Here, we discuss a case of an FJC treated with both decompression and placement of a Coflex ILS device.