A 75 years male patient was investigated for micturition difficulty and diagnosed to have carcinoma prostate. Patient was referred for skeletal scintigraphy to look for any bone secondaries.

Tc99m MDP bone scan (Fig 1) shows normal tracer distriuion in the skeleton except for a well circumscribed homogenously intense hot spot in the left pubic region. On careful evaluation, the hot spot is found not exactly corresponding to the bony margins of the left pubic bone - body, superior or inferior ramus. Comparing with the posterior view indicates the hot spot to be most anterior probably overlying left pubic bone.

Left lateral view scan (Fig 2) confirmed the hot spot to be much anterior and superfical to the left pubic bone. Urinary contamination artifact was ruled out by removing the clothing.

So what could be this hot spot?

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Answer:
The intensity of the hot spot is equal to that of the urinary activity in the bladder.
Physical examination of the patient revealed a large sliding hernia into left scrotum which according to the patient has been there for several years. Our scan finding indicates presence of dumb-bell type herniation of urinary bladder into the scrotum.

Seyfettin Ilgan et al from Turkey have reported a similar case report in the April 2007 issue of The Japanese Journal of Nuclear Medicine.