Brain Perfusion SPECT: Injection Environment

When performing a brain perfusion study like the one shown, what environment should be prepared for the patient immediately before and during radiopharmaceutical injection to ensure accurate mapping of baseline cerebral blood flow?

1. AA brightly lit procedure room with standard background noise and normal patient conversation allowed during injection
2. BA quiet, dimly lit room with eyes open and minimal auditory and visual stimulation before and throughout injection
3. CA darkened room with the patient instructed to keep both eyes tightly closed throughout the entire uptake period
4. DA standard waiting area where the patient may watch television or use their phone until transfer to the camera room