This article explores the significant role of metaphor in audio description (AD) for blind and partially sighted (BPS) individuals, particularly within contemporary art museums. Using the Conceptual Metaphor Theory (CMT), we examine how metaphors enable the translation of visual elements into accessible verbal narratives. We propose a methodology for analysing metaphors based on three dimensions: textual type (painting, sculpture, and installation), grammatical nature (objects, actions, modifiers, and qualifiers), and communicative intent (novelty, directness, and deliberateness). This approach highlights the essential role of metaphors in bridging the gap between visual art and verbal descriptions for BPS people. Furthermore, we introduce a classification of recurrent metaphorical cases, such as personification, synaesthesia, cultural reference, form, technique, participation, optionality, opposition, double marker, and vocal emphasis. Our findings emphasise the importance of metaphors as cognitive tools that not only enhance comprehension but also enrich the aesthetic experience for BPS individuals, making art more accessible and engaging. This research provides a robust framework for future AD practices and advocates for creative yet clear descriptions that respect and engage diverse audiences.