Columbia University College of Physicians and Surgeons 3 articles published in JoVE Neuroscience Novel Passive Clearing Methods for the Rapid Production of Optical Transparency in Whole CNS Tissue Jiwon Woo1,2,3, Eunice Yoojin Lee4, Hyo-Suk Park1,3, Jeong Yoon Park1,3, Yong Eun Cho1,2,3 1Department of Neurosurgery, Gangnam Severance Hospital, Yonsei University College of Medicine, 2Brain Korea 21 PLUS Project for Medical Science, Yonsei University, 3The Spine and Spinal Cord Institute, Biomedical Center, Gangnam Severance Hospital, Yonsei University College of Medicine, 4Columbia University College of Physicians and Surgeons Here, we present two novel methodologies, psPACT and mPACT, for achieving maximal optical transparency and subsequent microscopic analysis of tissue vasculature in the intact rodent whole CNS. Medicine Second Harmonic Generation Signals in Rabbit Sclera As a Tool for Evaluation of Therapeutic Tissue Cross-linking (TXL) for Myopia Mariya Zyablitskaya1, E. Laura Munteanu2, Takayuki Nagasaki1, David C. Paik1 1Department of Ophthalmology, Columbia University College of Physicians and Surgeons, 2Confocal and Specialized Microscopy Shared Resource, Herbert Irving Comprehensive Cancer Center, Columbia University This protocol describes techniques for evaluating chemical cross-linking of the rabbit sclera using second harmonic generation imaging and differential scanning calorimetry. Medicine The In Ovo Chick Chorioallantoic Membrane (CAM) Assay as an Efficient Xenograft Model of Hepatocellular Carcinoma Michael Li1,2, Ravi R. Pathak5, Esther Lopez-Rivera3, Scott L. Friedman1, Julio A. Aguirre-Ghiso4, Andrew G. Sikora5 1Department of Medicine, Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, 2Department of Otolaryngology, Icahn School of Medicine at Mount Sinai, 3Division of Nephrology, Columbia University College of Physicians and Surgeons, 4Departments of Medicine, Hematology and Medical Oncology, Icahn School of Medicine at Mount Sinai, 5Bobby R. Alford Department of Otolaryngology - Head and Neck Surgery, Baylor College of Medicine The chick chorioallantoic membrane (CAM) is immunodeficient and highly vascularized, making it a natural in vivo model of tumor growth and angiogenesis. In this protocol, we describe a reliable method of growing three-dimensional, vascularized hepatocellular carcinoma (HCC) tumors using the CAM assay.