DOI: 10.21276/aimdr.2019.5.1.MC1 Original Article ISSN (O):2395-2822; ISSN (P):2395-2814 Annals of International Medical and Dental Research, Vol (5), Issue (1) Page 1 Section: Neurosurgery Surgical Outcome of Endoscopic Cysto-Cisternostomy for Arachnoid Cyst. Md Moshiur Rahman 1 , Umme Kulsum Sharmin Zaman 2 1 Assistant Professor (current charge), Neurosurgery Department, HFRCMC, Dhaka, Bangladesh 2 Professor and Head, Anatomy Department, Delta Medical College, Dhaka, Bangladesh Received: November 2018 Accepted: November 2018 Copyright: © the author(s), publisher. Annals of International Medical and Dental Research (AIMDR) is an Official Publication of “Society for Health Care & Research Development”. It is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non- commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. ABSTRACT Background: Arachnoid cysts are present in 1% of the populace and generally found in the temporal, frontal, pineal and posterior fossa, frontotemporal fossa. Clinical and radiologic introductions can vary incredibly. In spite of serious research, it is as yet easily proven wrong which patients will profit by medical procedure. Objective: This study intends to research the pre-treatment parameters impacting the result after neuro-endoscopic treatment of arachnoid cysts. Methods: A review investigation of 14 patients who experienced an endoscopic fenestration of arachnoid cysts between 2012 to 2017. Results: In symptomatic patients, 85.71 percent of cases have improved clinically. The best results in treating symptoms related to intracranial hypertension, acute neurological defects and macrocrania and seizure were found. Conclusion: The clinical outcome and complication rate vary by technique and symptomatology, although the outcome after the endoscopic cysto cysternostomy is satisfactory. Keywords: Arachnoid cyst, Endoscopy, Cysto-Cisternostomy. INTRODUCTION Arachnoid cysts (TAC) were first described as serious cysts inside the arachnoid membrane' in 1831. [1] They account for about 1 percent of all intracranial masses and an estimated prevalence of 1 percent. [2,3] Arachnoid cysts can be primary or secondary. Primary arachnoid cysts are congenital (present at birth), resulting from abnormal development of the brain and spinal cord during early pregnancy. Secondary arachnoid cysts are less common, and result from head injuries, meningitis, tumors, or as a complication of brain surgery. Signs and symptoms depend on the location and size of the cyst and may include headache, nausea and vomiting, seizures, hearing and visual disturbances, vertigo, and difficulties with balance and walking. Primary (congenital) arachnoid cysts are benign accumulation of clear fluid between the dura and the brain substance throughout the cerebrospinal axis in relation to the arachnoid membrane and do not communicate with the subarachnoid space. [4,5] Due to computed tomography and magnetic resonance imaging numbers have increased with previous diagnosis in recent years. [6] The majority of these incidental findings are small asymptomatic cysts. Arachnoid cysts are generally equally Name & Address of Corresponding Author Dr. Md Moshiur Rahman, Assistant Professor (current charge), Neurosurgery Department, HFRCMC, Dhaka, Bangladesh. distributed between men and women and between the left and the right. However, medium cranial fossa and cerebellopontine angle arachnoid cysts are an exception with a left to right ratio of 2.5 and a male predominance for temporary arachnoid cysts. Costa Rica et al. Classified TAC in three categories according to volume and characteristics. There is no significant correlation between this classification and symptomatology. [7,8] A few decades ago, brain agenesis was thought to cause cyst appearance. It is now thought that primary or congenital arachnoid cysts are caused by the splitting of the arachnoid membrane and the progressive accumulation of spinal fluid (CSF). [9-13] Other theories suggest a post- partum trauma causing an arachnoid membrane split, an embryonic mesenchymal condensation disorder or a deviant CSF flow. Secondary arachnoid cysts are caused by trauma, inflammation, surgery, infection or a metabolic disorder. In contrast to non- acquired cysts their membranes consist of fibrotic tissue and they can contain hemosiderin or inflammatory cells. Arachnoid cysts remain generally stable, but spontaneous involvement, disappearance and growth have been shown. Although considered benign lesions, secondary problems can occur in some cases either spontaneously or due to trauma, such as subdural hematoma, subdural hygroma or intra- cystic bleeding. Intra-cystic hemorrhages and subdural hematomas occur mainly in TAC and ipsilateral. The most common symptoms of TAC are