Molecular Imaging of Hypoxia

Hypoxia is a condition of inadequate O₂ to support metabolic processes, which occurs when there is interruption in the vascular supply, or when tissues lose their O₂ supply acutely. When healthy cells are extremely deprived of O₂, they always die. Since tumor cells are increasingly vulnerable, they can have to an adaptation that negatively affects their response to treatment. Tumor cells quickly adapt to hypoxia by decelerating their rate of growth, and standard chemotherapy is lethal to cells at a level relative to growth.

In the article, Krohn, Link, and Mason inform that hypoxia can be measured with a probe that competes directly with intracellular O₂, in which the indicator was not trapped when O₂ supply was sustaining demand, but was maintained when O₂ supply was insufficient to accommodate all of the produced electrons in the electron-transport chain. Using this method, the researchers reported results that indicated that micro-autoradiographs that ¹⁴C-labeled derivatives of N-alkyl-2-nitroimidazoles were locked in hypoxic cells that were still alive.

Other methods of measuring Hypoxia include Direct MRI and Optical Imaging. The MRI methods are preferred since they debar the complication of transient radioactivity. Besides, MRI equipment is readily available. The MRI method tells apart paramagnetic deoxy-Hb and O₂Hb. Results from correct T2* weighted imaging indicate alterations in vascular oxygenation. Using the Optical Imaging method, tissue oxygenation can be evaluated directly using near-infrared oximetry to measure fractional oxygenation of Hemoglobin. When this method is applied on the heart, critical changes in O₂ result to stress in the heart while tumors adjust to inveterate hypoxia.

The identification of hypoxic tissues has remedial impacts on the state of several diseases, such as stroke, diabetes and myocardial ischemia. A study based on various sources of literature reveal that the imaging-identi%uFB01ed hypoxia predicts poor survival in several cancer settings. However, Krohn, Link, and Mason argue that the next phase of analyses measuring the prognostic value of hypoxia imaging in neoplasms have to provide substantial data on the level at which it is an autonomous prognostic marker.

In conclusion, molecular imaging of hypoxia is clinically significant from two perspectives-it is important in identifying a group of patients who would positively respond to medical interventions aimed at defeating the therapeutic confines of hypoxia, and in detailing, via serial imaging, that the medical intervention strategy reduced the magnitude of hypoxic illness.