Has there been any unusual curvature?
You may be describing superficial thrombophlebitis of the penis (an uncommon disease known as Mondor's disease). This is an inflammatory reaction to a clot within the vein. This subsequently causes blockages and dilation of the vein. It is typically painless, but can be painful.
Diagnosis is via ultrasound which shows blockage of the vessels. Treatment is with anti-inflammatories (i.e. aspirin or ibuprofen) and most resolve within 4-6 weeks. If it persists, then surgery may be necessary.
I would definitely have your husband follow up with his Physician.
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