A device for removing a tissue from an eye of a patient during a medical procedure, the device comprising: a housing; a cutter extending from a distal end of the housing along a longitudinal axis, the cutter comprising: an outer cutting tube coupled to the housing, the outer cutting tube including an outer surface and an inner surface; an outer port formed in the outer cutting tube, the outer port comprising an aperture extending from the outer surface to the inner surface of the outer cutting tube, the outer port sized to receive the tissue; an inner cutting tube disposed within the outer cutting tube, the inner cutting tube having a distal tube end slidable along the longitudinal axis between a retracted position proximal to the outer port and an extended position distal to the outer port; and a tissue sensor positioned on the cutter and configured to measure a characteristic of the tissue received within the outer port to identify when the tissue entering the outer port is non-target tissue and when the tissue entering the outer port is target tissue; an actuator positioned within the housing and configured to reciprocate the inner cutting tube to slide the distal tube end between the retracted position and the extended position to open and close the outer port and cut the tissue; and an arresting mechanism configured to halt the motion of the inner cutting tube in the retracted position; wherein the arresting mechanism comprises a first fastening element shaped and configured to interact with a second fastening element disposed on a proximal portion of the cutter within the housing to halt motion of the inner cutting tube in the retracted position. a housing; a cutter extending from a distal end of the housing along a longitudinal axis, the cutter comprising: an outer cutting tube coupled to the housing, the outer cutting tube including an outer surface and an inner surface; an outer port formed in the outer cutting tube, the outer port comprising an aperture extending from the outer surface to the inner surface of the outer cutting tube, the outer port sized to receive the tissue; an inner cutting tube disposed within the outer cutting tube, the inner cutting tube having a distal tube end slidable along the longitudinal axis between a retracted position proximal to the outer port and an extended position distal to the outer port; and a tissue sensor positioned on the cutter and configured to measure a characteristic of the tissue received within the outer port to identify when the tissue entering the outer port is non-target tissue and when the tissue entering the outer port is target tissue; an outer cutting tube coupled to the housing, the outer cutting tube including an outer surface and an inner surface; an outer port formed in the outer cutting tube, the outer port comprising an aperture extending from the outer surface to the inner surface of the outer cutting tube, the outer port sized to receive the tissue; an inner cutting tube disposed within the outer cutting tube, the inner cutting tube having a distal tube end slidable along the longitudinal axis between a retracted position proximal to the outer port and an extended position distal to the outer port; and a tissue sensor positioned on the cutter and configured to measure a characteristic of the tissue received within the outer port to identify when the tissue entering the outer port is non-target tissue and when the tissue entering the outer port is target tissue; an actuator positioned within the housing and configured to reciprocate the inner cutting tube to slide the distal tube end between the retracted position and the extended position to open and close the outer port and cut the tissue; and an arresting mechanism configured to halt the motion of the inner cutting tube in the retracted position; wherein the arresting mechanism comprises a first fastening element shaped and configured to interact with a second fastening element disposed on a proximal portion of the cutter within the housing to halt motion of the inner cutting tube in the retracted position.