Can many superficial feet veins be safely treated with sclerotherapy? (Photo)

Yes, surface veins of the feet (and hands) can be treated - we do so regularly. Your situation is interesting in that the veins seem to have increased following your perforator ablation and phlebectomy. It would be very helpful to see a detailed ultrasound of the current venous drainage of your lower legs. Before attempting to treat the foot veins, I would want to make certain that there was not any additional reflux or increased venous pressure that needed to be addressed first. Ongoing reflux "upstream" could make the foot treatment less successful, or even make the veins worse. In the meantime, please use good (20-30mmHg) closed toe compression stockings to try and relieve your symptoms.