Raman Spectroscopy for the Endoscopic Diagnosis of Esophageal, Gastric, and Colonic Diseases

Globally white-light endoscopy with biopsy sampling is the gold standard diagnostic modality for esophageal, gastric, and colonic pathologies. However, there is overwhelming evidence to highlight the deficiencies of an approach based predominantly on eyeball visualization. Biopsy sampling is also problematic due in part to excessive sampling and hence attendant cost. Various innovations are currently taking place in the endoscopic domain to aid operators in diagnosis forming. These include narrow band imaging which aims to enhance the surface anatomy and vasculature, and confocal laser endomicroscopy which provides real time histological information. However, both of these tools are limited by the skill of the operator and the extensive learning curve associated with their use. There is a gap therefore for a new form of technology that relies solely on an objective measure of disease and reduces the need for biopsy sampling. Raman spectroscopy (RS) is a potential platform that aims to satisfy these criteria. It enables a fingerprint capture of tissue in relation to the protein, DNA, and lipid content. This focused review highlights the strong potential for the use of RS during endoscopic gastroenterological examination.

A Review of Probe-Based Confocal Laser Endomicroscopy for Pancreaticobiliary Disease

Confocal laser endomicroscopy (CLE) is a novel in vivo imaging technique that can provide real-time optical biopsies in the evaluation of pancreaticobiliary strictures and pancreatic cystic lesions (PCLs), both of which are plagued by low sensitivities of routine evaluation techniques. Compared to pathology alone, CLE is associated with a higher sensitivity and accuracy for the evaluation of indeterminate pancreaticobiliary strictures. CLE has the ability to determine the malignant potential of PCLs. As such, CLE can increase the diagnostic yield of endoscopic retrograde cholangiopancreatography and endoscopic ultrasound, reducing the need for repeat procedures. It has been shown to be safe, with an adverse event rate of ≤1%. Published literature regarding its cost-effectiveness is needed.

Optical Biopsy with Probe-based Confocal Laser Endomicroscopy for Prediction of Residual Barrett’s Esophagus after Complete Radiofrequency Ablation (RFA)– A Pilot Study.

Introduction: Radiofrequency ablation (RFA) of Barrett’s esophagus (BE) is associated with a high rate of complete eradication and a reduced risk of disease progression. Nevertheless, recent data indicate that about one third of patients had disease recurrence after reaching complete remission. Aim: To evaluate whether probe-based confocal laser endomicroscopy (pCLE) can determine complete eradication of BE as compared to histopathology from biopsy after complete RFA for optimized diagnosis in real-time and guide subsequent therapy. Materials and Methods: Consecutive patients undergoing RFA for treatment of BE were prospectively included. pCLE was performed after complete eradication (CE) of dysplasia (CE-D) or intestinal metaplasia (CE-IM) was reached. CE was defined as complete eradication of BE as documented by histopathology obtained from mucosal biopsies. Residual BE was defined as the presence of intestinal metaplasia or dysplasia in standard surveillance biopsies. Two experienced gastrointestinal pathologists confirmed pathology findings. Results: Based on histopathological analysis 33% of patients (3/9) had high-grade dysplasia, and 67% (6/9) had low-grade dysplasia. RFA was successfully performed in all patients (median age 60±10 yrs.). Three (33%) patients underwent endoscopic mucosal resection (EMR) followed by RFA. Patients received a median of 3±0.6 treatment sessions of RFA after which EGD with biopsies and pCLE were performed. pCLE documented CE-D and CE-IM in 78% and 44% of patients, while histology did in 90% and 67% respectively. Overall sensitivity, specificity, and accuracy of pCLE for real time diagnosis of residual BE after completed RFA treatment was 80% (95% CI 0.43–0.98), 75% (95% CI 0.28–0.98), and 78% (95% CI 0.36–0.98), respectively. Positive and negative predictive values were 80% (95% CI 0.42–0.98) and 75% (95% CI 0.28–0.98). Conclusion: pCLE is yet not reliable for In vivo diagnosis of residual BE after complete RFA in real time. Larger, prospective studies are now highly warranted to further proof this initial concept.

Regenerative Neurorehabilitation and Neuromuscular Pathology / The Japanese Journal of Rehabilitation Medicine

Regenerative medicine, which aims to restore, replace or regenerate cells and tissues using novel approaches such as iPS therapy, is currently a big issue in the field of rehabilitation medicine. Neurological recovery has been proved using marmoset monkeys with spinal cord lesions and Hematoxylin-Eosin and Luxol fast blue staining were adopted to identify the increased number of neurons at the spinal cord level. In regenerative medicine, pathophysiological findings demonstrating the recovery of motor units can provide direct evidence of neuromuscular function. In the field of rehabilitation medicine, the final common pathway, e.g. intramuscular nerve fibers and neuromuscular junctions, will be the target used to identify the recovery of motor function. Present physiatric modalities such as electrical or magnetic stimulations and therapeutic exercises will serve as the strategic applications used in neuromuscular regeneration treatments. The methylene blue vital staining method is a classical technique that when combined with the recently developed functional fluorescent protein staining along with transgenic procedures and confocal endomicroscopy examinations will illuminate our investigations into the degree of regenerative success obtained. These neuromuscular pathologies at the spinal cord level as well as the lower motor neuron level will allow us to more clearly determine the efficacy of various physical modalities used in rehabilitation medicine. The regenerative medicine era will require rehab efforts not only for treating spinal cord lesions but also for treating brain damaged patients in the future.

Endoscopic Imaging in Barrett's Oesophagus: Applications in Routine Clinical Practice and Future Outlook

The practice for endoscopic surveillance of Barrett's oesophagus has evolved from "blind" or random 4 quadrant biopsies (Seattle protocol) to a more "intelligent" targeted biopsy approach. This evolution has been possible due to the rapid advances in endoscopic imaging technology and expertise in the last decade. Previous endoscopes had relatively poor image resolution that often did not allow the subtle mucosal changes associated with dysplastic Barrett's mucosa to be identified. Newer endoscopic imaging techniques available today may allow endoscopists to identify areas of dysplasia or malignancy and target biopsies accordingly. These modalities which include narrow band imaging, chromoendoscopy, autofluorescence imaging, and confocal endomicroscopy as well as a few novel imaging modalities on the horizon will be discussed further.