In Response to Early Functional Imaging in Juvenile Angiofibroma

Abstract

We would like to thank you for the opportunity to reply to the letter "Functional imaging in juvenile angiofibroma" by Sakthivel et al. and the authors for their interest and feedback concerning our article "Early postoperative magnetic resonance in the diagnosis of persistent angiofibroma." 1 In two recent studies, Sakthivel et al. 2,3 proposed and validated a promising postoperative protocol with prostatespecific membrane antigen (PSMA) positron emission tomography-computed tomography (PET-CT) for postoperative surveillance of juvenile angiofibroma (JA).The authors report three major criticisms regarding the limitations of using contrast enhanced magnetic resonance (cMR) as early postoperative imaging.They underline the difficulty of carrying out cMR with nasal packing: indeed, as reported in our previous studies, 1,4 we remove nasal packing within 2 days after surgery, usually before postoperative cMR. However, even when the patient underwent cMR before its removal, no issue of image acquisition or interpretation was observed.They pointed out the impossibility to perform cMR in patients who are hemodynamically instable; however, in our opinion, if there are concerns about hemodynamic instability, the priority should not be early identification of JA persistence, but rather patient stabilization. In our series, all patients were able to tolerate MR without any hemodynamic issues.The authors also comment that the use of three criteria to define cMR positivity increases the risk of dubious cases. Indeed, despite the use of the abovementioned criteria, the result of our study is dichotomic: cMR is considered positive if all the criteria are satisfied, and negative if at least one is not.Therefore, in our opinion, cMR remains the best exam for JA postoperative baseline imaging. In fact, in addition to being radiation-free, its high soft-tissue resolution (0.6 mm) provides precise information on the site and size of residual JA and allows monitoring it over time. We believe functional imaging such as with PSMA PET-CT is an interesting second-line option in cases with extensive scarring and/or critical situations with suspicious cMR. Routine use of PET-CT, however, in addition to exposing young patients to radiation, may not have an acceptable cost-benefit balance.Undoubtedly, further research is warranted to define the best use of these imaging studies after JA resection and compare them appropriately.