en Neuroscience Review <strong>Background and Aim</strong>: EETA (Endoscopic Endonasal Transsphenoidal Approach) is a preferred choice for pituitary tumors. EETA offers minimal invasiveness, fewer complications, and better outcomes than the sublabial or transseptal microscopic approach. EETA has three approaches: mononostril endoscopic transsphenoidal approach, binostril endoscopic transsphenoidal approach, and one and a half nostril approach. This study aims to compare three different EETAs and compare between microscopic transsphenoidal approach, transcranial approach and EETA.<br> <strong>Methods and Materials/Patients</strong>: To provide up-to-date information, we concisely reviewed these three EETAs. Using the keywords of &ldquo;neuroendoscopy&rdquo;, &ldquo;META&rdquo; (Mononostril Endoscopic Transsphenoidal Approach), &ldquo;OETA&rdquo; (One and a half nostril Approach), &ldquo;BETA&rdquo; (Binostril Endoscopic Transsphenoidal Approach), &ldquo;pituitary adenoma&rdquo;, &ldquo;EETA&rdquo;, &ldquo;endoscopy&rdquo;, &ldquo;transsphenoidal approach&rdquo;, &ldquo;transcranial approach for pituitary adenoma&rdquo; and &ldquo;microscopic transsphenoidal approach&rdquo;. We retrieved all the relevant articles from Google Scholar, PubMed, and Medline. Then, we reviewed them and critically analyzed them.<br> <strong>Results</strong>: In BETA there is free and easy movement of surgical instruments in the surgical field and a broader view of the sphenoid sinus and it is an excellent approach to resect large tumors. The META is suitable in tumors with limited involvement of the intra-sellar and supra-sellar area. The mononostril approach is not suitable and has some limitations for the following situations: a crowded narrow nasal cavity, a harder tumor with the invasive appearance or significant suprasellar extension, and lesions other than pituitary adenomas. The OETA provides a sufficient surgical corridor for a 2-surgeon/4 or 3-hands technique with a minimal injury of the nose and good operative results, free and easy movement of surgical instruments in the surgical field, low post-operative morbidity, and good post-operative quality of life.<br> <strong>Conclusion</strong>: In EETA, knowing the size and consistency of tumor, general versus invasive pituitary adenoma, and the extent of parasellar and suprasellar extension, is essential. If we cannot reach a pituitary macroadenoma with a trans-sphenoidal approach, then we can use a transcranial approach for the removal of the tumor. The microscopic transsphenoidal approach is suitable for pediatric pituitary adenoma. Mononostril endoscopy, Binostril endoscopy, One and a half nostril endoscopy, Transsphenoidal approach 15 22 http://irjns.org/browse.php?a_code=A-10-400-2&slc_lang=en&sid=1 Shahrokh Yousefzadeh-Chabok kazemimd@msn.com 10031947532846006396 10031947532846006396 No Guilan Road Trauma Research Center, Guilan University of Medical Sciences, Rasht, Iran. Guive Sharifi kazemimd@msn.com 10031947532846006397 10031947532846006397 No Department of Neurosurgery, Skull Base Research Center, School of Medicine, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Mohammad Ghorbani kazemimd@msn.com 10031947532846006398 10031947532846006398 No Department of Neurosurgery, Division of Vascular and Endovascular Neurosurgery, School of Medicine, Firoozgar Hospital, Iran University of Medical Sciences, Tehran, Iran Mohammad Samadian kazemimd@msn.com 10031947532846006399 10031947532846006399 No Department of Neurosurgery, Skull Base Research Center, School of Medicine, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Navid Kalani navidkalani@ymail.com 10031947532846006400 10031947532846006400 No Department of Anesthesiology, Critical Care and Pain Management Research Center, Jahrom University of Medical Sciences, Jahrom, Iran. Ali Kazeminezhad kazemimd@msn.com 10031947532846006401 10031947532846006401 Yes Department of Neurosurgery, Peymanieh Hospital, Jahrom University of Medical Sciences, Shiraz, Iran.