PHOTHERA 600

Description of Event or Problem

PATIENT'S SETTINGS WERE NOT SUCCESSFULLY SAVED WITH THE CHANGED MIN ON OF 10, AND ON THE FIRST TREATMENT (NOMINALLY 200MJ FRONT AND BACK), THE DEVICE DELIVERED LIGHT FOR 1:02 AND 1:56. PATIENT HAD SIGNIFICANT ERYTHEMA AND REACHED OUT TO THEIR HCP AT GEISSINGER.

Additional Manufacturer Narrative

AN INTERNAL INVESTIGATION INITIATED ON MARCH 4, 2026, IDENTIFIED A FIRMWARE/HARDWARE INTERACTION ISSUE IN MODEL (B)(4) DEVICES USING SOFTWARE VERSION 3.17. THE ISSUE IS SPECIFICALLY TIED TO THE REV H "NO SENSOR" CLEARLINK MAIN BOARD AND THE REV D "AMS OSRAM" REMOTE SENSOR BOARD. TESTING CONFIRMED THE UV SENSOR GAIN CAN FAIL TO APPLY CORRECTLY DURING THE INITIALIZATION FUNCTION AT POWER-UP. WHEN THIS OCCURS, THE GAIN MAY DEFAULT TO A LOWER VALUE (4 OR 5) INSTEAD OF THE CONFIGURED VALUE (7 FOR UVB), LEADING TO INCORRECT CALIBRATED OUTPUT CALCULATIONS. THE PATIENT'S OVEREXPOSURE WAS A DIRECT RESULT OF THIS "DROPPED" GAIN STATE COMBINED WITH THE FAILURE OF THE DEVICE TO SAVE UPDATED SETTINGS TO THE INTENDED MIN_ON THRESHOLD. A "STOP SHIP" WAS ISSUED ON MARCH 4, 2026. THE PLANNED 806 REPORT COVERS (B)(4) DEVICES AND INCLUDES A TEMPORARY FIELD FIX TO ADJUST THE MIN_ON VALUE. THIS ADJUSTMENT IS DESIGNED TO ENSURE THE DEVICE OPERATES IN FIXED CALIBRATION OR DETECTS A DROPPED GAIN TO PREVENT FUTURE OVEREXPOSURE EVENTS.