Abstract PURPOSE: To demonstrate a hold-up of part of the fluorescein bolus in the arm as a result of arm position. METHOD: Case report. We obtained a fluorescein angiogram with a calibrated confocal scanning laser ophthalmoscope in a 20-year-old healthy subject. During and after injection, the upper arm was held in approximately 60 degrees abduction, 65 degrees exorotation, and slight anteflexion. In the late venous phase, the subject moved the upper arm on the injected side to a more neutral, downward position. RESULTS: We measured a distinct rise in fluorescence level about 10 seconds after movement of the arm. The most likely explanation is relief of a partial obstruction of the venous drainage, which had been caused by the position of the upper arm described above. CONCLUSION: Impaired venous drainage of the injected arm caused by exorotation and abduction of the upper arm is a potentially common cause of delayed dye arrival or unexpectedly reduced contrast level during fluorescein angiography. Therefore, arm position needs attention in fluorescein angiography.