Objective: Superb microvascular imaging is a Doppler technique that increases the visibility of small vessels and gives quantitative information about tissue blood supply by measuring the vascular index. In this study, it is aimed to evaluate the long-term and postradiotherapy changes in blood flow of buried de-epitelized flaps in breast reconstruction by using the quantitative values obtained through superb microvascular imaging. Materials and Methods: Retrospective review of the 14 patients who underwent nipple-sparing breast-conserving surgery and immediately breast reconstruction with a de-epitelized extended latissimus dorsi flap was done. In order to demonstrate the effect of radiotherapy on flaps microvascular circulation, patients were evaluated using superb microvascular imaging postoperative first week, first month, and postradiotherapy first week and sixth month. The normal distribution of the data was evaluated with the Shapiro–Wilk test. Paired samples t-test was used for comparisons. Results: According to the paired samples t-tests, postoperative first week mean vascular index was higher than postoperative first month and postradiotherapy first week (P <.05). Besides, postradiotherapy first week mean vascular index was higher than postoperative first month and also than postradiotherapy sixth month (P <.05). Conclusion: Radiotherapy can affect the results of breast reconstruction by endothelial and fibrotic injury. In this study, the changes in the microvascular circulation of the latissimus dorsi flap were discussed and found to increase at postoperative and postradiotherapy early period related to inflammation and not decreased significantly at long-term follow-up after radiotherapy.