Intraoperative fluorescence imaging with aminolevulinic acid detects grossly occult breast cancer: a phase II randomized controlled trial.

BACKGROUND: Re-excision due to positive margins following breast-conserving surgery (BCS) negatively affects patient outcomes and healthcare costs. The inability to visualize margin involvement is a significant challenge in BCS. 5-Aminolevulinic acid hydrochloride (5-ALA HCl), a non-fluorescent oral prodrug, causes intracellular accumulation of fluorescent porphyrins in cancer cells. This single-center Phase II randomized controlled trial evaluated the safety, feasibility, and diagnostic accuracy of a prototype handheld fluorescence imaging device plus 5-ALA for intraoperative visualization of invasive breast carcinomas during BCS. METHODS: Fifty-four patients were enrolled and randomized to receive no 5-ALA or oral 5-ALA HCl (15 or 30 mg/kg). Forty-five patients (n = 15/group) were included in the analysis. Fluorescence imaging of the excised surgical specimen was performed, and biopsies were collected from within and outside the clinically demarcated tumor border of the gross specimen for blinded histopathology. RESULTS: In the absence of 5-ALA, tissue autofluorescence imaging lacked tumor-specific fluorescent contrast. Both 5-ALA doses caused bright red tumor fluorescence, with improved visualization of tumor contrasted against normal tissue autofluorescence. In the 15 mg/kg 5-ALA group, the positive predictive value (PPV) for detecting breast cancer inside and outside the grossly demarcated tumor border was 100.0% and 55.6%, respectively. In the 30 mg/kg 5-ALA group, the PPV was 100.0% and 50.0% inside and outside the demarcated tumor border, respectively. No adverse events were observed, and clinical feasibility of this imaging device-5-ALA combination approach was confirmed. CONCLUSIONS: This is the first known clinical report of visualization of 5-ALA-induced fluorescence in invasive breast carcinoma using a real-time handheld intraoperative fluorescence imaging device. TRIAL REGISTRATION: Clinicaltrials.gov identifier NCT01837225 . Registered 23 April 2013.

Improved detection of clinically relevant wound bacteria using autofluorescence image-guided sampling in diabetic foot ulcers.

Clinical wound assessment involves microbiological swabbing of wounds to identify and quantify bacterial species, and to determine microbial susceptibility to antibiotics. The Levine swabbing technique may be suboptimal because it samples only the wound bed, missing other diagnostically relevant areas of the wound, which may contain clinically significant bacteria. Thus, there is a clinical need to improve the reliability of microbiological wound sampling. To address this, a handheld portable autofluorescence (AF) imaging device that detects bacteria in real time, without contrast agents, was developed. Here, we report the results of a clinical study evaluating the use of real-time AF imaging to visualise bacteria in and around the wound bed and to guide swabbing during the clinical assessment of diabetic foot ulcers, compared with the Levine technique. We investigated 33 diabetic foot ulcers (n = 31 patients) and found that AF imaging more accurately identified the presence of moderate and/or heavy bacterial load compared with the Levine technique (accuracy 78% versus 52%, P = 0·048; adjusted diagnostic odds ratio 7·67, P < 0·00022 versus 3·07, P = 0·066) and maximised the effectiveness of bacterial load sampling, with no significant impact on clinical workflow. AF imaging may help clinicians better identify the wound areas with clinically significant bacteria, and maximise sampling of treatment-relevant pathogens.

Optically-tracked handheld fluorescence imaging platform for monitoring skin response in the management of soft tissue sarcoma.

Standard clinical management of extremity soft tissue sarcomas includes surgery with radiation therapy. Wound complications (WCs) arising from treatment may occur due to bacterial infection and tissue breakdown. The ability to detect changes in these parameters during treatment may lead to earlier interventions that mitigate WCs. We describe the use of a new system composed of an autofluorescence imaging device and an optical three-dimensional tracking system to detect and coregister the presence of bacteria with radiation doses. The imaging device visualized erythema using white light and detected bacterial autofluorescence using 405-nm excitation light. Its position was tracked relative to the patient using IR reflective spheres and registration to the computed tomography coordinates. Image coregistration software was developed to spatially overlay radiation treatment plans and dose distributions on the white light and autofluorescence images of the surgical site. We describe the technology, its use in the operating room, and standard operating procedures, as well as demonstrate technical feasibility and safety intraoperatively. This new clinical tool may help identify patients at greater risk of developing WCs and investigate correlations between radiation dose, skin response, and changes in bacterial load as biomarkers associated with WCs.

Neutrophils mediate blood-spinal cord barrier disruption in demyelinating neuroinflammatory diseases.

Disruption of the blood-brain and blood-spinal cord barriers (BBB and BSCB, respectively) and immune cell infiltration are early pathophysiological hallmarks of multiple sclerosis (MS), its animal model experimental autoimmune encephalomyelitis (EAE), and neuromyelitis optica (NMO). However, their contribution to disease initiation and development remains unclear. In this study, we induced EAE in lys-eGFP-ki mice and performed single, nonterminal intravital imaging to investigate BSCB permeability simultaneously with the kinetics of GFP(+) myeloid cell infiltration. We observed a loss in BSCB integrity within a day of disease onset, which paralleled the infiltration of GFP(+) cells into the CNS and lasted for ∼4 d. Neutrophils accounted for a significant proportion of the circulating and CNS-infiltrating myeloid cells during the preclinical phase of EAE, and their depletion delayed the onset and reduced the severity of EAE while maintaining BSCB integrity. We also show that neutrophils collected from the blood or bone marrow of EAE mice transmigrate more efficiently than do neutrophils of naive animals in a BBB cell culture model. Moreover, using intravital videomicroscopy, we demonstrate that the IL-1R type 1 governs the firm adhesion of neutrophils to the inflamed spinal cord vasculature. Finally, immunostaining of postmortem CNS material obtained from an acutely ill multiple sclerosis patient and two neuromyelitis optica patients revealed instances of infiltrated neutrophils associated with regions of BBB or BSCB leakage. Taken together, our data provide evidence that neutrophils are involved in the initial events that take place during EAE and that they are intimately linked with the status of the BBB/BSCB.

Local assessment of myelin health in a multiple sclerosis mouse model using a 2D Fourier transform approach.

We present an automated two-dimensional Fourier transform (2D-FT) approach to analyze the local organization of myelinated axons in the spinal cord. Coherent anti-Stokes Raman scattering (CARS) microscopy was used to observe lesions in a commonly used animal model of multiple sclerosis (MS), experimental autoimmune encephalomyelitis (EAE). A 2D-FT was applied on the CARS images to find the average orientation and directional anisotropy of the fibers within contiguous image domains. We introduce the corrected correlation parameter (CCP), a measure of the correlation between orientations of adjacent domains. We show that in the EAE animal model of MS, the CCP can be used to quantify the degree of organization/disorganization in the myelin structure. This analysis was applied to a large image dataset from animals at different clinical scores and we show that some descriptors of the CCP probability density function are strongly correlated with the clinical scores. This procedure, compatible with live animal imaging, has been developed to perform local in situ evaluation of myelinated axons afflicted by EAE.