Abstract: To explore the strategies and methods to improve the diagnosis and treatment of central neuroblastoma. METHODS: We retrospectively analyzed eight cases of central neuroblastoma admitted to our hospital from August 2004 to August 2009, and summarized their clinical manifestations, imaging manifestations, pathological features and microsurgical treatment effects. Lin Guozhong, Department of Neurosurgery, Peking University Third Hospital RESULTS: The tumor was located in the anterior part of the lateral ventricle or near the interventricular foramen, and showed a wide base connected with the wall of the lateral ventricle or the hyaline septum. Multiple vesicles were seen on the edge and inside of the tumor, and calcification was common. The T1WI and T2WI phases showed equal or slightly high signal, and mild to moderate enhancement after enhancement. Immunohistochemical staining showed positive neurosynuclein in all cases. Eight cases were treated by microsurgery, including six cases of total resection and two cases of subtotal resection. One case died of postoperative complications, and seven cases have not recurred since the follow-up. Conclusion: The imaging manifestation of central neuroblastoma has certain characteristics and is an important reference for preoperative diagnosis. Microsurgical resection of the tumor is the best treatment with good prognosis. Keywords: central neurocytoma, diagnosis, microsurgery Hassoun et al. first reported central neurocytoma (CNC) in 1982 [1], which is a rare central nervous system tumor, a neuronal and mixed neuronal glial tumor, WHO grade II [2]. The number of clinical cases is small, and the diagnosis and treatment of the disease are still controversial. Eight cases were admitted to our hospital from August 2004 to August 2009, and this paper summarizes their clinical manifestations, imaging manifestations and treatment methods in the light of the literature. 1. Clinical data 1.1 General data: 3 male and 5 female cases, age 18-49 years old, average 27.6 years old. There were no obvious symptoms in the early stage, and the main manifestations in the late stage were headache, nausea, vomiting, vision loss, one case with tinnitus, one case with personality change, and one case with mild paralysis of the right limb. Six of the cases had optic papilloedema in the fundus, and the rest had no neurological localization signs. 1.2 Imaging manifestations: cranial MRI scan and enhancement examination were performed in all cases, among which 7 cases had cranial CT examination, and the CT scan was mainly isointense, with calcification in 6 cases and low-density cystic area in 7 cases. The T1WI was inhomogeneous isosignal, and the T2WI was isosignal or high signal. 8 cases showed multiple cystic lesions at the edge and inside, 6 cases showed calcification, and the solid part of the tumor showed mild to moderate inhomogeneous enhancement in the enhancement scan. All of them were located in the midline, 5 cases were connected with lateral ventricular wall, 2 cases were connected with hyaline septum, one side was predominantly growing to the opposite side, with different degrees of hydrocephalus due to obstruction of Monro’s foramen. 1.3 Surgical methods: 5 cases had a lateral ventricular approach through the frontal cortex, all of them were fistulized in the frontal middle gyrus or between the frontal and middle gyrus sulci, and 3 cases had a transcallosal approach. During surgery, most of the tumors were gray-brown, brittle and soft, with rich blood supply and easy bleeding. 1.4 Pathological examination: routine pathological examination and immunohistochemical staining were performed, including synaptophysin (Syn) and glial fibrillary acidic protein (GFAP), etc. 2.1 Treatment results: 8 cases were treated by microsurgery, including 6 cases of total resection and 2 cases of subtotal resection, and those without total resection were treated with radiotherapy after surgery. 1 case with mild paralysis of the right limb was aggravated by the frontal cortical lateral ventricular approach, and recovered after treatment and rehabilitation in about 2 months. 1 case died of postoperative cardiovascular complications, and 7 cases have not recurred since the follow-up. 2.2 Pathological results: All cases were positive for Syn, only one case showed weakly positive for GFAP, and the remaining 7 cases were negative. The pathological diagnosis was central neuroblastoma in all cases. 3, Discussion 3.1 Epidemiology and clinical manifestations: CNC is generally benign, only a few occur malignantly, accounting for about 0.25%-0.5% of CNS tumors, and the age of onset is overwhelmingly 20-40 years old, with no gender differences [3-5]. In the early stage, there may be no obvious symptoms, but in the late stage, the tumor blocks the cerebrospinal fluid circulation pathway and causes obstructive hydrocephalus and cranial hypertension, resulting in obvious headache, vomiting, optic papilledema and ataxia [4-6]. Tumor compression or invasion of the surrounding brain tissue may present other symptoms such as light limb paralysis and personality changes. The age of onset and clinical manifestations of this group of patients are similar to the literature. 3.2 Imaging features: CNC is mostly located in the midline, connected to the lateral ventricular wall or hyaline septum by a wide base, with one side predominantly growing to the opposite side, with different degrees of hydrocephalus due to obstruction of the foramen of Monro [4, 7]. MRI T1WI showed heterogeneous iso-signal and T2WI showed iso- or high-signal with multiple cystic lesions and calcifications at the margins and inside; enhancement scans showed mild to moderate heterogeneous intensification in the solid part of the tumor, and a few showed significant intensification; some of them could be seen as proliferative vascular flow [4-7]. Magnetic resonance spectroscopy showed increased choline and glycine (Gly) and decreased Nacetylaspartate (NAA) and creatine [8]. 3.3 Differential diagnosis: The low incidence of CNC and the lack of characteristic imaging manifestations require differentiation from other intracerebroventricular tumors, but a definitive diagnosis relies on postoperative pathology. (1) Choroid plexus papilloma: those located in the lateral ventricles are more likely to be found in the delta, mostly in children. It is a papillary mass with equal signal in T1WI and equal or slightly high signal in T2WI, and most of them are uniformly and significantly enhanced after enhancement. Syn negative; ③ oligodendroglioma: rare in intracerebroventricular region, striped calcification and cystic lesions are common in MRI, low signal in T1WI, high signal in T2WI, heterogeneous mild to moderate intensification, tumor cells Syn negative. 3.4 Treatment: Surgical resection is the preferred treatment for CNC. The purpose of surgery is to clarify the diagnosis, reconstruct the cerebrospinal fluid pathway and remove the tumor as much as possible with safety. Surgical approaches include transcallosal and transcortical approaches [5, 6]. We believe that the transcallosal lateral ventricular approach provides a good surgical view and avoids postoperative complications due to excessive damage to the frontal lobe. One patient in this group had worsening of limb light paralysis after transcallosal cortical lateral ventricular approach, which may be related to the damage to the frontal lobe. However, when the tumor is located on one side, large in size and accompanied by obvious dilatation of that lateral ventricle, the transcortical lateral ventricular approach is more appropriate. The tumor is usually soft and easy to aspirate, and the blood supply is rich. The surface of the intraventricular part of the tumor is mostly smooth, but the tumor tip is often not clearly demarcated from the surrounding tissues. During surgery, attention should be paid to show the ventricular vein, choroid plexus, monro foramen and other ventricular landmarks in order to control the depth of resection. The thalamic vein and the thalamus should be protected during the operation to ensure the safe resection of the tumor. After surgery, an extraventricular drain should be placed and left until it is clear to prevent intraventricular hemorrhage and hydrocephalus. Some authors believe that postoperative radiotherapy can be given to increase the efficacy of the tumor regardless of whether it is completely resected or not, while some authors believe that radiotherapy is not necessary for complete resection, but should be given for incomplete resection or tumor recurrence, especially for atypical or aggressive CNC [4, 9, 10]. Chemotherapy for CNC is less reported and can be a trial treatment for recurrent CNC that cannot be resected or has been treated with radiation.