Suprasellar arachnoid cysts are very rare in children, and they have been rarely reported in the past. suprasellar arachnoid cysts were first reported by Barlow in 1935, and they were first diagnosed by CT in 1977. With the improvement of MRI techniques, the number of cases has gradually increased. Historically these cysts have been referred to as third ventricular cysts, suprasellar arachnoid cysts] or suprasellar-suprasellar pool arachnoid cysts, etc. In recent years, I have encountered more than a dozen cases of suprasellar pool cysts in the clinic, which have been treated with good results by neuroendoscopy. Combined with literature review, they are summarized as follows: The formation of suprasellar pool cysts may be related to the development of Liliequist’s membrane. The main clinical symptoms are as follows: symptoms of increased intracranial pressure: increased head circumference, headache, vomiting; abnormal endocrine function: short stature, precocious puberty; neurological symptoms: delayed motor and intellectual development, ataxic gait, intentional tremor; nodding phenomenon; ocular symptoms: decreased visual acuity, visual field defects; and psychomotor abnormalities. Suprasellar pool arachnoid cysts often present on CT as obstructive hydrocephalus with enlargement of the lateral and third ventricles, and are easily overlooked by physicians and treated as general obstructive hydrocephalus surgery. MRI has a clearer picture of the disease. There are four distinctive features of suprasellar pool arachnoid cysts on MRI: upward and forward displacement of the pituitary stalk and optic cross; upward and backward displacement of the papillary body by compression; flattening of the ventral aspect of the pontine brain by compression; and the Mickey-Mouse sign: the third ventricle and both lateral ventricles are significantly dilated, showing the typical Mickey-Mouse sign on axial images. Previously, there are several different ways to treat suprasellar pool arachnoid cysts in children, including open microsurgery to remove the cyst, craniotomy to open the cyst, cyst-abdominal shunt, stereotactic puncture, and so on. However, all have different disadvantages. Craniotomy is too invasive and has a poor prognosis. The shunt surgery is difficult to puncture the drainage tube into the cyst, and some children, on the contrary, have experienced rapid expansion of the cyst after the ventricular pressure became smaller in the past, leading to the aggravation of symptoms. With the increasing maturity of neuroendoscopic technology, cystostomy using neuroendoscopy at home and abroad has become the best option for dealing with arachnoid cysts in the suprasellar pool. Specific surgical procedure: Children need to be operated under general anesthesia. In the supine position, a straight incision of 1 cm in front of the right coronal suture and 2 cm next to the midline is taken, usually only about 3 cm long, and only one hole is drilled in the skull, which is punctured into the lateral ventricle to visualize the cyst wall blocking the interventricular foramen. After electrocoagulation, the cyst wall is incised and enlarged to a direct 1.5 cm window into the cyst cavity, and then important structures such as the dorsal saddle, pituitary gland, pituitary stalk and Willis ring can be clearly seen, electrocautery and opening at the base wall of the cyst, and some of the thickened arachnoid-like structures need to be cut and opened. The endoscope is withdrawn, the bony foramen is closed, and the procedure is completed with full suturing of the scalp. Postoperative recovery is usually rapid, with the child being able to get out of bed the next day and being discharged after a few days of normal temperature observation Children with arachnoid cysts in the suprasellar pool require regular postoperative follow-up evaluation. Because some children have a combination of different degrees of brain developmental abnormalities, regular postoperative follow-up is essential. The postoperative evaluation includes both clinical and imaging components. Clinical symptoms generally improve significantly after surgery. Postoperative MRI images show a significant reduction in cyst volume, and it should be noted that although the dilated ventricles may be reduced, the ventricles are still significantly enlarged compared to those of normal children.