It sounds like you are describing testicular microlithiasis, the deposition of multiple tiny calcifications in the testes. As for how and when to follow-up, or if you even need follow-up at all, recommendations are conflicting and evolving, so you should consult a urologist who is up-to-date with the medical literature. For more info: https://www.mayoclinic.org/diseases-conditions/testicular-cancer-care/expert-answers/microlithiasis/faq-20058074