Virtual reality (VR) systems have grown in popularity as an immersive modality for daily activities such as gaming, socializing, and working. However, this technology is not always accessible for people with photosensitive epilepsy (PSE) who may experience seizures or other adverse symptoms when exposed to certain light stimuli (e.g., flashes or strobes). How can VR be made more inclusive and safer for people with PSE? In this paper, we report on a series of semi-structured interviews about current perceptions of accessibility in VR among people with PSE. We identify 12 barriers to accessibility that fall into four categories: physical VR equipment, VR interfaces and content, specific VR applications, and individual differences in sensitivity. Our findings allow researchers and practitioners to better understand the meaning of photosensitive accessibility in the context of VR, and provide a step towards enabling people with PSE to enjoy the benefits offered by immersive technology.