Final answer:
The CTDIw for a 6-month-old baby under the same CT scanner settings as an adult would be higher, since the amount of radiation a patient receives varies with their size. However, a specific value can't be determined without more information.
Step-by-step explanation:
The CTDIw (Computed Tomography Dose Index) is a measure that reflects the dose of radiation a patient receives during a CT scan. For adults, the average CTDIw for an abdomen CT is approximately 3.0 cGy. However, the radiation dose a patient receives can significantly vary based on their size. Since a 6-month-old baby is much smaller than an adult, the same CT scanner settings would result in a higher dose of radiation. Based on the given reference table, the CTDIw for various tissues in the body, the CTDIw for a fetus is between 3.2-3.6 cGy, while the breast tissue, amniotic fluid, and placenta all have CTDIw values ranging from 0.9-1.8 cGy. Therefore, it can be assumed that the CTDIw for a 6-month-old baby, whose body size and composition are different from that of an adult, would be lower than the 3.0 cGy value for an adult abdomen CT scan.
Unfortunately, without specific information on how CTDIw variates with patient size, it's not possible to provide a precise estimation on the CTDIw for a 6-month-old baby using the same CT scan settings. It is recommended that the CT scan settings should be modified based on the size and anatomical area of interest to ensure as low as reasonably achievable (ALARA) principle.
Learn more about CTDIw