A molecular breast imaging (MBI) unit includes a housing, a first detector unit, and a second detector unit. The housing is configured to be positioned in an imaging position for imaging an object. The first detector unit includes a first nuclear medicine (NM) imaging detector secured in the housing. The first detector unit is configured to acquire first imaging information of the object when the housing is in the imaging position. The second detector unit includes a second NM imaging detector secured in the housing. The second detector unit is configured to acquire second imaging information of the object when the housing is in the imaging position. The housing includes an opening disposed between the first and second detector units. The opening is configured to allow access by a biopsy assembly to the object with the housing in the imaging position.