NHS Shetland has applied for planning permission to build a “weather proof enclosure” for the MRI scanner.
The health board is also looking to build a link corridor from the Gilbert Bain Hospital to the enclosure, and will amend the car park as a result.
It will be reduced by one car parking space overall, with 10 bike stand spaces added.
The plans were launched with council planners today (Monday).
Former NHS Shetland chief executive Michael Dickson said in May said they hoped to have the MRI scanner up and running by the middle of next year.
Once in use, the scanner is hoped to significantly reduce the number of patient journeys to the mainland.