Glossary

Fluorodeoxyglucose – This is a radiopharmaceutical analog of glucose used in PET scanning. It is injected into the veins with the circulation then distributing it throughout the body. Cells that use a high amount of glucose (brain, kidney and cancer cells) will absorb this molecule and partially metabolize it. The byproducts with an attached radioisotope will remain in the cell until the isotope decays thus the cell is “marked” by the isotope. PET scanning will identify areas rich in the isotope, creating an image that shows areas where a high amount of metabolism of the FDG is occurring.

18F-FDG, as a glucose analog, is taken up by high-glucose-using cells such as brain, kidney, and cancer cells, where phosphorylation prevents the glucose from being released again from the cell, once it has been absorbed. The 2′ hydroxyl group (—OH) in normal glucose is needed for further glycolysis (metabolism of glucose by splitting it), but 18F-FDG is missing this 2′ hydroxyl. Thus, in common with its sister molecule 2-deoxy-D-glucose, FDG cannot be further metabolized in cells. The 18F-FDG-6-phosphate formed when 18F-FDG enters the cell thus cannot move out of the cell before radioactive decay. As a result, the distribution of 18F-FDG is a good reflection of the distribution of glucose uptake and phosphorylation by cells in the body.

Referring to fetoscopy or an endoscopic procedure on a fetus or other structures within the amniotic space of a pregnant woman’s uterus.

This is an endoscopic procedure done on a fetus or other structures within the amniotic cavity of a woman’s uterus during pregnancy.

Fibroblast growth factors (AKA FGFs) – These are a family of growth factors involved in angiogenesis, wound healing, and embryonic development. They are involved in a number of the cell proliferation and differentiation processes involved in growth and maturation as well as healing.

Fibroblastic Growth Factor Receptor 2.  A protein that plays an important role bone growth in the head and other tissues during embryonic development.

A protein believed to be involved in regulating bone growth by controlling the conversion of cartilage to bone.

A FK506 binding protein belonging to the immunophillin family. This protein binds the immunosuppressant molecule tacrolimus (originally designated FK506), which is used in treating patients after organ transplant and patients suffering from autoimmune disorders. The FKBP-tacrolimus complex inhibits the phosphatase calcineurin that triggers transduction in the T-lymphocyte transduction pathway.

Fluid attenuated inversion recovery – This is a sequence used in magnetic resonance imaging which suppresses fluids such as CSF. The sequence accentuates parenchymal abnormalities, including edema and gliosis. FLAIR imaging is the most sensitive MRI method for identification of acute subarachnoid hemorrhage.

FMS-like tyrosine kinase – A gene expresed in cancerous cells that drives the synthesis of Vascular endothelial growth factor receptor 1 by tyrosine protein kinase activity. The result is release in the control of cell proliferation and differentiation.

Fetal myelomeningocele repair:  This refers to the in utero surgical closure of the myelomeningocele spinal defect prior to birth of the effected fetus.