BACKGROUND: We have often encountered difficulties in identifying small liver cancers during surgery. Fluorescent imaging using indocyanine green (ICG) has the potential to detect liver cancers through the visualization of the disordered biliary excretion of ICG in cancer tissues and noncancerous liver tissues compressed by the tumor. METHODS: ICG had been intravenously injected for a routine liver function test in 37 patients with hepatocellular carcinoma (HCC) and 12 patients with metastasis of colorectal carcinoma (CRC) before liver resection. Surgical specimens were investigated using a near‐infrared light camera system. Among the 49 subjects, the 26 patients examined during the latter period of the study (20 with HCC and 6 with metastasis) underwent ICG‐fluorescent imaging of the liver surfaces before resection. RESULTS: ICG‐fluorescent imaging identified all of the microscopically confirmed HCCs (n = 63) and CRC metastases (n = 28) in surgical specimens. Among the 63 HCCs, 8 tumors (13%, including 5 early HCCs) were not evident grossly unless observed by ICG‐fluorescent imaging. Five false‐positive nodules (4 large regenerative nodules and 1 bile duct proliferation) were identified among the fluorescent lesions. Well‐differentiated HCCs appeared as uniformly fluorescing lesions with higher lesion‐to‐liver contrast than that of moderately or poorly differentiated HCCs (162.6 [71.1‐218.2] per pixel vs 67.7 [‐6.3‐211.2] per pixel, P < .001), while CRC metastases were delineated as rim‐fluorescing lesions. Fluorescent microscopy confirmed that fluorescence originated in the cytoplasm and pseudoglands of HCC cells and in the noncancerous liver parenchyma surrounding metastases. ICG‐fluorescent imaging before resection identified 21 of the 41 HCCs (51%) and all of the 16 metastases that were examined. CONCLUSIONS: ICG‐fluorescent imaging enables the highly sensitive identification of small and grossly unidentifiable liver cancers in real time, enhancing the accuracy of liver resection and operative staging. Cancer 2009. © 2009 American Cancer Society.

The needle puncture approach, using 16G to 21G needles, resulted in a reproducible decrease of disc height and magnetic resonance imaging grade. The ease of the procedure and transfer of the methodology will benefit researchers studying disc degeneration.

Intervertebral disc (IVD) degeneration is an often investigated pathophysiological condition because of its implication in causing low back pain. As human material for such studies is difficult to obtain because of ethical and government regulatory restriction, animal tissue, organs and in vivo models have often been used for this purpose. However, there are many differences in cell population, tissue composition, disc and spine anatomy, development, physiology and mechanical properties, between animal species and human. Both naturally occurring and induced degenerative changes may differ significantly from those seen in humans. This paper reviews the many animal models developed for the study of IVD degeneration aetiopathogenesis and treatments thereof. In particular, the limitations and relevance of these models to the human condition are examined, and some general consensus guidelines are presented. Although animal models are invaluable to increase our understanding of disc biology, because of the differences between species, care must be taken when used to study human disc degeneration and much more effort is needed to facilitate research on human disc material.Keywords Intervertebral disc degeneration Á Animal models Á In vivo Á In vitro All of the authors contributed equally to this publication and are listed simply in alphabetical order.

Despite the high prevalence of intervertebral disc disease, little is known about changes in intervertebral disc cells and their regenerative potential with ageing and intervertebral disc degeneration. Here we identify populations of progenitor cells that are Tie2 positive (Tie2+) and disialoganglioside 2 positive (GD2+), in the nucleus pulposus from mice and humans. These cells form spheroid colonies that express type II collagen and aggrecan. They are clonally multipotent and differentiated into mesenchymal lineages and induced reorganization of nucleus pulposus tissue when transplanted into non-obese diabetic/severe combined immunodeficient mice. The frequency of Tie2+ cells in tissues from patients decreases markedly with age and degeneration of the intervertebral disc, suggesting exhaustion of their capacity for regeneration. However, progenitor cells (Tie2+GD2+) can be induced from their precursor cells (Tie2+GD2−) under simple culture conditions. Moreover, angiopoietin-1, a ligand of Tie2, is crucial for the survival of nucleus pulposus cells. Our results offer insights for regenerative therapy and a new diagnostic standard.

PRP isolated from autologous blood may be useful as a source of anabolic growth factors for stimulating chondrocytes to engineer cartilage tissue.