Value and limitations of testicular scanning by in vivo labelling of RBC with 99mTc.

When a scrotal affection cannot be diagnosed confidently by correlation of clinical history and physical examination, testicular scanning with 99mTc is a useful adjunct diagnostic modality. In vivo labelling of red blood cells with 99mTc was achieved by prior oral administration of 200 mg of stannous chloride. This helped to obtain satisfactory scintigraphy with a rectilinear scanner. This procedure was found to be useful in the adult with recent tender testicle in whom the torsion of the testis could not be clinically differentiated from epididymo-orchitis. Another area of scan's valuable clinical application was in the early diagnosis of testicular abscess in patients with epididymo-orchitis not responding immediately to antibiotic therapy. The study also proved to be a useful, non-invasive method for follow-up assessment of a case of torsion of the testis where detorsion and orchiopexy was performed as well as in case of rupture of a testis after orchiorrhapy.