A magnetic resonance imaging system, the system comprising: a magnetic field device configured to generate a magnetic field within a measurement volume and to generate a magnetic fringe field external to the measurement volume, wherein the measurement volume is configured to accommodate at least a portion of a patient; a ferromagnetic housing configured to envelop the magnetic field device, the housing having a first portion and a second portion wherein: the housing includes a proximal end and a distal end along a longitudinal axis of the MRI system, the housing further includes a housing opening at the proximal end for enabling insertion of at least a portion of a patient within the measurement volume, the second portion of the housing includes at least a portion of the proximal end of the housing, the first portion of the housing includes at least a portion of the distal end of the housing; and a plate, having a plate opening, positioned external to the housing adjacent the second portion of the housing at a predetermined non-zero distance from the proximal end of the housing, wherein the plate opening is aligned with a corresponding housing opening in the housing to allow insertion of at least a portion of the patient therethrough, and wherein the plate comprises a metal alloy, the metal alloy comprises a ferromagnetic material and wherein thickness of the first portion of the housing is less than the thickness of the second portion of the housing, such that the plate and different thicknesses of the first and second portions (324, 326) cause the magnetic fringe field to be reduced in a region adjacent the plate opening compared to an opposite region adjacent the distal end of the housing such that the generated magnetic fringe field is asymmetric with respect to a center of the measurement volume. a ferromagnetic housing configured to envelop the magnetic field device, the housing having a first portion and a second portion wherein: the housing includes a proximal end and a distal end along a longitudinal axis of the MRI system, the housing further includes a housing opening at the proximal end for enabling insertion of at least a portion of a patient within the measurement volume, the second portion of the housing includes at least a portion of the proximal end of the housing, the first portion of the housing includes at least a portion of the distal end of the housing; and the housing includes a proximal end and a distal end along a longitudinal axis of the MRI system, the housing further includes a housing opening at the proximal end for enabling insertion of at least a portion of a patient within the measurement volume, the second portion of the housing includes at least a portion of the proximal end of the housing, the first portion of the housing includes at least a portion of the distal end of the housing; and a plate, having a plate opening, positioned external to the housing adjacent the second portion of the housing at a predetermined non-zero distance from the proximal end of the housing, wherein the plate opening is aligned with a corresponding housing opening in the housing to allow insertion of at least a portion of the patient therethrough, and wherein the plate comprises a metal alloy, the metal alloy comprises a ferromagnetic material and wherein thickness of the first portion of the housing is less than the thickness of the second portion of the housing, such that the plate and different thicknesses of the first and second portions (324, 326) cause the magnetic fringe field to be reduced in a region adjacent the plate opening compared to an opposite region adjacent the distal end of the housing such that the generated magnetic fringe field is asymmetric with respect to a center of the measurement volume.