The brainstem is connected to the thalamus upward and the spinal cord downward, and is an important hub for the transmission of sensation from the whole body to the brain and for the brain to command the whole body, and is closely related to human consciousness, breathing and heartbeat. Since brainstem tumor resection surgery may aggravate the neurological damage and even threaten the patient’s life, this area was considered as a forbidden area for surgery in the past. However, with the advancement of microsurgery technology, the forbidden area has been broken through and many patients have had their brainstem tumors surgically removed and achieved good quality of life after surgery. Common tumors of the brainstem include gliomas, ventricular meningiomas, and vascular reticulocytomas. In addition to tumors, a common vascular disease is cavernous hemangioma (or cavernous vascular malformation). Brain stem occupying lesions are rare in the elderly and can occur in all other age groups. Among them, astrocytomas and glioblastomas are mostly seen in children and adolescents, while the rest of the lesions are mostly seen in adult patients. In children, the disease duration is short and rapid; it often causes severe brainstem symptoms within a short period of time; in adults, the disease duration is long and slow, and progressive brainstem symptoms appear gradually. The typical manifestation of brainstem tumor is ipsilateral lower motor neuron palsy with contralateral upper motor neuron palsy, which is called “crossed palsy”. The common symptom is headache, and posterior occipital pain is the most common. If the tumor is located in the midbrain, the patient may have strabismus, upward vision and eyelid drooping; if the tumor is located in the pontine brain, the patient may have facial sensory disorder, facial palsy, diplopia when looking to the affected side due to abducens nerve palsy, dizziness, ataxia and vomiting when the pontine arm is involved; if the tumor is located in the medulla oblongata, the patient may have symptoms of posterior cranial nerve palsy, such as dysphagia, choking and coughing when eating, nasal speech, inability to extend the tongue. Patients with medullary tumors have posterior cranial nerve palsy symptoms, such as dysphagia, choking and coughing, nasal speech, inability to extend tongue, etc. As for auxiliary examination, magnetic resonance imaging (MRI) is the most effective means of examination, and CT is better for acute hemorrhage. Diffuse gliomas often show diffuse thickening of the pontine brain in the T1 phase of MRI, with occasional focal enhancement; diffuse high signal crosses the entire pontine brain in the T2 phase and often extends into the midbrain and medulla. Focal gliomas have focal low signal on T1 with uniform enhancement or no enhancement, or show cystic nodules with tumor, and high signal on T2. Spongiform hemangiomas appear as irregularly shaped high-density or mixed-density lesions on CT, with punctate calcifications and mildly enhancing or non-enhancing lesions, with little surrounding edema. This has been described as a “popcorn”-like change surrounded by a low signal band due to iron-containing heme deposits. Vascular reticulocytoma (or hemangioblastoma) is a vascular tumor, mostly located in the medulla oblongata, and is often parenchymal or cystic, with significant parenchymal enhancement. Ventricular meningiomas occur within or next to the fourth ventricle and tend to show mixed density (on CT) or signal (on MRI) with heterogeneous enhancement. Because of the dense concentration of important anatomical structures in the brainstem, the decision to intervene surgically needs to be made with special care. In diffuse gliomas, there is usually no indication for surgery, and the infiltrative growth of the tumor makes extensive resection impossible; its histopathology is usually determinable based on the characteristic MRI presentation, and biopsy to confirm the diagnosis is unnecessary. Similarly, in benign parietal gliomas, which typically invade the entire parietal lid and progress slowly, experimental resection or biopsy is not necessary. The best treatment is usually just a shunt with follow-up and a controlled biopsy if progression occurs. Gliomas suitable for resection are: well-defined, with a surrounding brainstem that is displaced rather than infiltrated, and progressively more symptomatic. These include: extended cervical medullary gliomas, dorsal ectodermal gliomas, and certain focal endophytic tumors. Although these lesions appear to be well-defined on imaging, they are not enveloped and grow more or less invasively along their borders. Therefore, true total resection is inappropriate because of the risk of damage to the nuclei and long tracts of the peripheral cranial nerves. For midbrain tumors, extensive resection is most likely to injure the extraocular motor nuclei and the white matter pathways that coordinate isotropic gaze; for dorsal ectopia and focal endogenous pontine tumors, the facial and spreading nuclei are the most vulnerable. Medulla oblongata tumors are the most at risk because of their proximity to the posterior group of cranial nerve nuclei and respiratory centers. Given the high risk in brainstem tumor resection, many hospitals use intraoperative neurophysiological monitoring to help localize the relevant anatomical structures, to alert when signs of damage are present, and to modify the surgical approach accordingly. Electromyography (EMG) of cranial nerves can be evoked by stimulation to identify the location of cranial nerves on the surface of focal tumors or near convex tumors, and thus improve the surgical approach. During resection, EMG recordings may also alert the surgeon that the nerve or nucleus in question is being affected or that damage has occurred. Somatosensory evoked potentials (SSEPs) and brainstem auditory evoked potentials provide feedback on the state of the white matter conduction tracts passing through the brainstem and can warn of damage that will occur during resection. Theoretically, this allows the surgeon to change the surgical approach before injury occurs. The surgical approach and strategy should be individualized depending on the site and extent of tumor involvement and the nature of the tumor. We usually choose the Poppen approach for midbrain parietal tumors; the pterygoid point approach or the infratemporal approach for lateralized midbrain tumors; the infratemporal or infratemporal-sigmoid sinus anterior approach for ventral growth of pontine tumors; the posterior suboccipital sigmoid sinus approach for lateralized pontine tumors; and the median suboccipital approach for both dorsal pontine and medullary tumors. The general principles of surgery are: to decide the approach by the location of the mass, and to cut at the nearest brainstem surface; hemangiopericytoma should avoid resection in blocks, and for some giant types, resection in blocks can be tried after adequate electrocoagulation after eliminating the main blood supply; cavernous hemangioma should first remove the stale blood in the tumor, and then separate along the peri-tumor glial proliferation layer; resection of glioma should depend on the situation, and generally aspirate inside the tumor first, and then outward to “normal”. If the patient has obstructive hydrocephalus or is at high risk of developing hydrocephalus in the perioperative period, CSF diversion is a mandatory consideration in the surgical plan. If the CSF circulatory pathway can be opened intraoperatively, it should be closely monitored postoperatively and a simultaneous shunt may be a good option. Extra-ventricular drainage can also be placed, and the drainage bottle can be gradually elevated and then removed 5-7 days after surgery, and then a ventriculo-abdominal shunt can be made if it is not possible. Serious postoperative complications of brainstem tumor include coma, central respiratory failure, swallowing difficulty resulting in aspiration, stress ulcers, etc., which may endanger patients’ lives in serious cases. With the advancement of surgical equipment and surgical techniques, as well as the improvement of postoperative critical patient monitoring, the brainstem, which was once a restricted area for surgery, has now been breached. Brainstem-occupying lesions can be removed with satisfactory results. The prognosis of brainstem-occupying lesions is related to their location, with fewer complications after resection of midbrain lesions and relatively more and more severe complications after resection of medulla oblongata lesions. The long-term prognosis is determined by the pathological nature of the lesion. Among them, patients with cavernous hemangioma and vascular reticulocytoma can be cured after surgical resection. Low-grade confined astrocytomas and ventricular meningiomas can be resected and treated with radiotherapy for long-term survival. Surgery for high-grade astrocytomas can provide decompression and temporary relief of neurological dysfunction, with poor long-term results. In contrast, surgery for diffuse astrocytomas is not beneficial and only conservative treatments such as chemotherapy, palliative radiotherapy, or dehydration are appropriate. Parietal gliomas usually have a benign natural history, and the best management of these tumors is to treat obstructive hydrocephalus with CSF diversion only. 80% of patients do not progress beyond a 10-year observation period. Biopsy and adjuvant therapy are feasible when there is progression. The following are some of the individual surgical cases: Example 1, before and after MRI images of medullary hemangiopontocellular tumor Figure 2, before and after MRI films of giant hemangiopontocellular tumor of the medulla oblongata