A system comprising: an optical element configured to receive an electromagnetic radiation, EMR, and focus the EMR along an optical axis to a focal region in a target tissue; a controller configured to direct the optical element along a first scan path, wherein a motion of the optical element along the first scan path is configured to traverse the focal region along a treatment path in the target tissue; and a cooling element (150, 400) down-beam from the optical element and configured to be removably attached to the system via three or more datums and to receive the focusing EMR, the cooling element (150, 400) comprising: a first window (112, 406) comprising a first proximal surface and a first distal surface; a second window (118, 410) down-beam from the first window (112, 406), the second window (118, 410) comprising a second proximal surface and a second distal surface (120, 416), wherein the second window (118, 410) is configured to contact the target tissue or a tissue adjacent to the target tissue via the second distal surface (120, 416), and wherein the first scan path is parallel to the second distal surface (120, 416) within 50 milliradians; and a coolant chamber (114, 418) located between the first distal surface of the first window (112, 406) and the second proximal surface of the second window (118, 410) and configured to receive a coolant. an optical element configured to receive an electromagnetic radiation, EMR, and focus the EMR along an optical axis to a focal region in a target tissue; a controller configured to direct the optical element along a first scan path, wherein a motion of the optical element along the first scan path is configured to traverse the focal region along a treatment path in the target tissue; and a cooling element (150, 400) down-beam from the optical element and configured to be removably attached to the system via three or more datums and to receive the focusing EMR, the cooling element (150, 400) comprising: a first window (112, 406) comprising a first proximal surface and a first distal surface; a second window (118, 410) down-beam from the first window (112, 406), the second window (118, 410) comprising a second proximal surface and a second distal surface (120, 416), wherein the second window (118, 410) is configured to contact the target tissue or a tissue adjacent to the target tissue via the second distal surface (120, 416), and wherein the first scan path is parallel to the second distal surface (120, 416) within 50 milliradians; and a coolant chamber (114, 418) located between the first distal surface of the first window (112, 406) and the second proximal surface of the second window (118, 410) and configured to receive a coolant. a first window (112, 406) comprising a first proximal surface and a first distal surface; a second window (118, 410) down-beam from the first window (112, 406), the second window (118, 410) comprising a second proximal surface and a second distal surface (120, 416), wherein the second window (118, 410) is configured to contact the target tissue or a tissue adjacent to the target tissue via the second distal surface (120, 416), and wherein the first scan path is parallel to the second distal surface (120, 416) within 50 milliradians; and a coolant chamber (114, 418) located between the first distal surface of the first window (112, 406) and the second proximal surface of the second window (118, 410) and configured to receive a coolant.