en Gamma Knife Radiosurgery Case report <p style="text-align: justify;">Background & Importance: The aim of this study was to demonstrate the result of transsphenoid microsurgery for Cushing disease in our&nbsp;center and comparing the results in details with other articles, to achieve the best decision for patients management in future.<br> Case Presentation: Between 1991 to 2015, 50 patients suffering from Cushing disease were operated. Before operation, endocrine tests&nbsp;and neuroimaging examinations were done for all patients and all of them were operated via transsphenoid approach. They were followed&nbsp;up in clinic with endocrine tests and imaging in regular intervals. During this study, 50 Cushing cases including 47 primary and three&nbsp;secondary tumors were operated. Thirty four (68%) tumors were microadenoma and 16 (32%) macroadenoma. A patient died due to postoperative&nbsp;fulminant meningitis (mortality=2%). Mean of follow-up was five years. Overall, 40 (80%) patients had remission after operation&nbsp;and 9 (18%) patients achieved no remission, three of them had macroadenoma and six microadenoma. During follow-up period, three (6%)&nbsp;patients had recurrence which needed second operation. In secondary tumor and in macroadenoma with cavernous sinus involvement, the<br> result was not good (33% and 0% remission, respectively).<br> Conclusion: Transsphenoid surgery is a safe and effective first choice method to manage Cushing disease compared to other treatment&nbsp;modalities. In recurrent or resistant cases, other modalities could help to manage patients.</p> Cushing Disease, Microadenoma, Cavernous Sinus, Transsphenoid Surgery 19 21 http://irjns.org/browse.php?a_code=A-10-31-1&slc_lang=en&sid=1 Masoud Mehrazin مسعود مهرآذین Mehrazin@yahoo.com 10031947532846003089 10031947532846003089 Yes MD, Neurosurgeon, Professor of Neurosurgery, TUMS, Shariati Hospital, Tehran, Iran. Reza Mirfallah رضا میرفلاح 10031947532846003090 10031947532846003090 No MD, Neurosurgeon, Arad Hospital, Tehran, Iran Hossein Bokaei حسین بکایی 10031947532846003091 10031947532846003091 No MD, ENT Surgeon, Arad Hospital, Tehran, Iran Mousa Sadr-Hosseini موسی صدر حسینی 10031947532846003092 10031947532846003092 No MD, ENT Surgeon, Associate Professor of ENT Surgery, TUMS, Imam Khomeini Hospital, Tehran, Iran