A clinical study of ocular motor nerve functions after petroclival meningioma resection.

BACKGROUND: Ocular motor dysfunction is one of the most common postoperative complications of petroclival meningioma. However, its incidence, recovery rate, and independent risk factors remain poorly explored. METHODS: A prospective analysis of 31 petroclival meningiomas was performed. Operative approaches were selected by utilizing a new 6-region classification of petroclival meningiomas we proposed. Two scores were used to evaluate the functions of the oculomotor and abducens nerves. Pearson correlation analysis and binary logistic regression analysis were used to identify independent risk factors for intraoperative oculomotor and abducens nerve injury. RESULTS: Postoperative new-onset dysfunctions in the pupillary light reflex and eye/eyelid movements as well as abducens paralysis were detected in eight (25.8%), ten (32.3%) and twelve (38.7%) cases, respectively. Their corresponding recovery rates after 6 months of follow-up were 75% (6/8), 80% (8/10), and 83.3% (10/12), respectively, and their mean times to start recovery were 4.03, 2.43, and 2.5 months, respectively. Tumor invasion into the suprasellar region/sphenoid sinus was the only risk factor for dysfunctions in both the pupillary light reflex (p = 0.001) and eye/eyelid movements (p = 0.002). Intraoperative utilization of the infratrigeminal interspace was the only risk factor for dysfunction in eyeball abduction movement (p = 0.004). CONCLUSIONS: Dysfunctions of the oculomotor and abducens nerves recovered within 6 months postoperatively. Tumor extension into the suprasellar region/sphenoid sinus was the only risk factor for oculomotor nerve paralysis. Eye/eyelid movements were more sensitive than the pupillary light reflex in reflecting nerve dysfunctions. Intraoperative utilization of the infratrigeminal interspace was the only risk factor for abducens nerve paralysis.

Clinical Characteristics and Surgical Features of Intracranial Fibrosarcoma.

BACKGROUND: Intracranial fibrosarcoma is an extremely rare neoplasm in the central nervous system. Insofar there were only sporadic case reports describing its features. The purpose of this study is to review the clinical and surgical features of cases who were treated in our department. METHOD: The authors retrospectively reviewed and detailed the clinical and surgical data obtained from 5 patients with fibrosarcoma who underwent treatment at our institute between January 2009 and January 2019. RESULTS: There were 3 males and 2 females including 2 juvenile and 3 senior patients. The most frequent sign was intermittent pain and vomiting. The location of the tumor included middle fossa, thalamus and midbrain, sellar and suprasellar region and right parietal-occipital lobe. Surgical observation demonstrated the consistency of the tumor was tenacious with abundant blood supply. Gross total resection was achieved in 2 cases. Pathological analysis showed spindle cells in a herringbone form with positive Vimentin staining in all 5 cases, with the absence of GFAP or S-100. All 5 patients were deceased eventually after a varied period of time after the first surgery. CONCLUSION: Intracranial fibrosarcoma was a highly malignant entity presented in the central nervous system. Surgery still remains the first-line treatment followed by radiotherapy, however, the prognostic outcome was very poor. Future studies should be more focused on accumulation of the relevant information on this disease thus hopefully in assisting to developing more optimized treatment.

Clinical presentation and mutation analysis of VHL disease in a large Chinese family.

Von Hippel-Lindau (VHL) disease is an autosomal dominantly inherited neoplastic disorder characterized by marked phenotypic variability and age-dependent penetrance. This disease is caused by germline mutations in the VHL tumor suppressor gene. Systematic physical examinations, imaging assessments and molecular genetic tests for the VHL gene were performed in a large Chinese VHL family. The examined Chinese VHL family, which has 25 members from four generations, including 7 diagnosed VHL patients and 2 asymptomatic mutation carriers. The average ages of first onset for generations I, II, and III were 37, 30 and 16, respectively. The male:female ratio among VHL patients was 6:1. Molecular genetic investigations detected the c.433C>T [p.Q145X] nonsense mutation in the VHL gene. Molecular modeling of the VHL-ElonginC- ElonginB-HIF-1α complex predicted that the p.Q145X mutation markedly alters the L7 loop structure of the ß-domain of the VHL protein (pVHL), destabilizes the VHL-HIF-1αcomplex, and induces the truncation of pVHL. We speculate that the p.Q145X nonsense mutation leads to relatively obvious familial aggregation. This mutation causes the type I phenotype of VHL disease and is associated with a high risk of retinal and central nervous system (CNS) hemangioblastomas (HGBs) and visceral cysts, but a low risk of renal cell carcinoma. Moreover, within a VHL family, the average ages of first onset became younger in successive generations, and the CNS HGBs are more likely to occur in male patients.

Recurrent petroclival meningiomas: clinical characteristics, management, and outcomes.

This study seeks to elucidate the prognostic predictors and outcomes of recurrent/progressive petroclival meningiomas (PCMs). We reviewed our cohort of 39 recurrent/progressive PCMs (27 females, 69.2%) and analyzed the results from the literature. Twenty-three patients underwent reoperations, 2 received radiotherapy alone, and 14 declined any treatment. During a follow-up of 70.4 months, 7 patients experienced a 2nd recurrence/progression (R/P) and 18 patients died. In the 23 patients, gross total resection (GTR), subtotal resection (STR), and partial resection (PR) were achieved in 8, 8, and 7 patients, respectively. The percentage of the 2nd R/P-free survival of GTR, STR, and PR was 88%, 67%, and 40%, respectively. The overall survival following the 1st R/P of GTR, STR, and PR was 88%, 63%, and 33%, respectively. Patients rejecting treatment suffered from significantly poor overall survival (7%; p = 0.001) and short survival duration (42.0 months; p = 0.016) compared with that of the patients receiving treatment (67% and 86.9 months). The GTR was the only independent favorable predictor. In the 21 included studies with 98 recurrent/progressive PCM patients, 17 patients presented with a 2nd R/P and 10 died of a 2nd R/P; patients undergoing observation had a significantly poor tumor regrowth control rate compared with patients undergoing surgery (p = 0.004) or radiotherapy alone (p < 0.001). Proactive treatment should be performed for patients with recurrent/progressive PCMs. Observation can lead to relentless outcome. GTR as a preferential therapeutic strategy should be pursued as far as possible on the condition of minimal functional impairment.

Surgical management and outcomes of petroclival meningiomas: a single-center case series of 259 patients.

BACKGROUND: Surgical management of petroclival meningiomas is challenging. Various and inconsistent outcome and prognostic factors of the lesions have been evaluated previously. In the present study, the surgical outcome, philosophy, and experience of petroclival meningiomas are detailed based on a large patient series. METHODS: A series of 259 patients with petroclival meningiomas (70 males and 189 females) were surgically treated. Clinical charts and radiographs were reviewed. Follow-up results were evaluated. RESULTS: The preoperative Karnofsky Performance Scale (KPS) score was 74.2 ± 10.5. The mean tumor size was 4.3 ± 1.0 cm. The gross total resection (GTR) rate was 52.5%. During a mean follow-up period of 55.3 months, recurrence/progression (R/P) occurred in 11 patients. The recent KPS score was 78.4 ± 22.7, it improved in 139 (57.2%) patients and stabilized in 53 (21.8%) patients, and 201 (82.7%) patients lived independently. The risk factors affecting the KPS score included (but were not limited to) age ≥ 60, preoperative KPS ≤ 60, and brainstem edema. The adverse factors contributing to R/P-free survival included (but were not limited to) non-total resection and the absence of the subarachnoid space. The R/P-free survival rate was 94.5% at 5 years and 91.2% at 9 years. The overall survival rate was 94.7% at 5 years and 94.7% at 9 years. CONCLUSIONS: Favorable outcomes from petroclival meningiomas could be achieved by microsurgery. Neurological function and quality of life were prioritized, and GTR was attempted. Risk factors should be considered in surgical schemes, and tumor recurrence should be aggressively monitored and treated.

[Microsurgical treatment for jugular foramen meningiomas].

OBJECTIVE: To explore the microsurgical treatment and clinical efficacies of jugular foramen meningiomas. METHODS: A total of 28 patients with jugular foramen meningiomas undergoing microsurgical operations at Beijing Tiantan Hospital during the period from April 1996 to April 2011 were analyzed retrospectively. The retrosigmoid suboccipital (n = 13), far lateral (n = 9), postauricular trans-supracondylar (n = 4) and trans-paracondylar approaches (n = 2) were used. RESULTS: Complete tumor resection was achieved in 18 patients and subtotal tumor resection in 10 patients. Twenty-two patients were followed up for a mean follow-up period of 3 years. The postoperative Karnofsky performance scale was above 80 in 19 patients. Twelve patients experienced hoarseness or bucking, 11 lived independently and 2 died of tumor recurrence. CONCLUSION: Jugular foramen meningiomas have a higher recurrence rate and severe cranial nerve damages may occur postoperatively. It is important to classify them into different clinical entities and choose appropriate surgical approaches and techniques so as to achieve satisfactory outcomes.

[Study on the meningoima using FT-mid-IR spectroscopy].

In the present investigation, 24 cases of meningoima tissues (including 12 cases of benign tumor and 12 cases of malignant tumor 12) were detected using FT-mid-IR spectroscopy linked with attenuated total reflectance (ATR) accessory. These FTIR spectra obtained from the above-mentioned meningoima tissues were analyzed and compared. Significant differences were found in the spectral features of different kinds of meningoima tissues for example fibrous type meningoima and endothelioid meningoima; and for the same type of meningoima tissues the significant differences in the spectram features can be also observed with the increase of grade malignancy. The malignant tumor can be distinguished primarily from benign tumor by the changes of position, shape and intensity of infrared absorption bands, particularly in the ranges of 1 000-1 500 cm(-1). The results show that the peak position of the bands (such as 1 160 cm(-1)) can be used to distinguish the characteristic of meningoima which are in agreement with the pathological results. The accuracy is larger than 85%. These results demonstrate that FT-mid-IR spectroscopy exhibits prospect to develop a novel, non-invasive and rapid method for the diagnosis the brain tumors.

[Therapeutic strategy for intrasellar cystic lesions].

OBJECTIVE: To make a clear distinction of intrasellar cystic lesions: craniopharyngioma (CR), Rathke's cleft cyst (RCC), cystic pituitary adenoma (PA) and intrasellar arachnoid cyst (AC). METHODS: A total of 72 adult patients underwent transsphenoidal approach for the removal of intrasellar cystic lesions. The authors conducted a study to (1) investigate preoperative clinical, biochemical and radiographic features of patients with CR, RCC, PA and AC; (2) identify clinicopathological features of independently predicting recurrence in CR, PA and RCC in adults. These adult patients included CR (n = 10), RCC (n = 27), cystic PA (n = 32) and 1 patient with AC (n = 1). RESULTS: The CR patients presented with hypopituitarism in 80% of cases. According to the biochemical criteria, the percentage of patients with a slight prolactin increase happened in PA (55.6%) and RCC (44.4%). Cystic PA had post-contrasting enhancement in cyst wall because of tumor tissue. Calcification detectable on computed tomographic scanning was present in 70% of CR patients. It was a significantly greater proportion compared to other diseases. Typical RCC was located between anterior and posterior pituitary and the contents in RCC were variable. Mass effects vanished post-operatively in all kinds of lesions. Long-term hormone replacement therapy was administered more in CR patients (60%) and diabetes insipidus than other lesions. One PA patient and 2 CR patients had recurrence during a follow-up of 12 - 52 months (mean: 34). RCC and AC had no recurrence. CONCLUSION: Craniopharyngioma, Rathke's cleft cyst, cystic pituitary adenoma and intrasellar arachnoid cyst are a spectrum of diseases with different therapeutic strategies. An accurate diagnosis of these lesions is essential so as to determine the type of treatment to improve outcome.

Malignant Progression Contributes to the Failure of Combination Therapy for Atypical Meningiomas.

OBJECTIVE: To investigate the independent risk factors for recurrence in intracranial atypical meningiomas (AMs) treated with gross total resection (GTR) and early external beam radiotherapy (EBRT). METHODS: Clinical, radiological, and pathological data of intracranial AMs treated with GTR-plus-early-EBRT between January 2008 and July 2016 were reviewed. Immunohistochemical staining for Ki-67 was performed. Kaplan-Meier curves and univariate and multivariate Cox proportional hazards regression analyses were used to explore independent predictors of tumor recurrence. Chi square test was performed to compare variables between subgroups. RESULTS: Forty-six patients with intracranial AMs underwent GTR and early EBRT. Ten (21.7%) recurred and three (6.5%) died during a median follow-up of 76.00 months. Univariate and multivariate Cox analyses revealed that malignant progression (MP) (P = 0.009) was the only independent predictor for recurrence, while Ki-67 was of minor value in this aspect (P = 0.362). MP-AMs had a significantly higher recurrence rate (P = 0.008), a higher proportion of irregularly shaped tumors (P = 0.013) and significantly lower preoperative Karnofsky Performance Scale (KPS) scores (P = 0.040) than primary (Pri) AMs. No significant difference in Ki-67 expression was detected between these subgroups (P = 0.713). CONCLUSIONS: MP was significantly correlated with an increased incidence of recurrence in GTR-plus-early-EBRT-treated intracranial AMs. Significantly higher frequencies of tumor relapse and irregularly shaped tumors and lower preoperative KPS scores were observed in MP-AMs compared with Pri-AMs. Ki-67 expression is of minor value in predicting tumor recurrence or distinguishing tumor origins in AMs.

MicroRNA-221/222 Inhibits the Radiation-Induced Invasiveness and Promotes the Radiosensitivity of Malignant Meningioma Cells.

The controversy of adjuvant radiotherapy of meningiomas is at least partially due to the insufficient understanding on meningioma cells' response to irradiation and the shortage of radiosensitivity-promotion methods. MicroRNA-221 and microRNA-222 were identified as critical regulators of radiosensitivity in several other tumors. However, their effect in meningiomas has yet to be confirmed. Therefore, the malignant meningioma IOMM-Lee cells were adopted, transfected with microRNA-221/222 mimics or inhibitors, and irradiated with different dosages. The effects of radiation and microRNA-221/222 were then assessed in vitro and in vivo. Radiation dose increases and microRNA-221/222 downregulation synergistically inhibited cell proliferation and colony formation, prevented xenograft tumor progression, and promoted apoptosis, but antagonistically regulated cell invasiveness. Pairwise comparisons revealed that only high-dose radiations (6 and 8 Gy) can significantly promote cell invasiveness in comparison with unirradiated counterparts. Further comparisons exhibited that downregulating the microRNA-221/222 expression can reverse this radiation-induced cell invasiveness to a level of untransfected and unirradiated cells only if cells were irradiated with no more than 6 Gy. In addition, this approach can promote IOMM-Lee's radiosensitivity. Meanwhile, we also detected that the dose rate of irradiation affects cell cycle distribution and cell apoptosis of IOMM-Lee. A high dose rate irradiation induces G0/G1 cell cycle arrest and apoptosis-promoting effect. Therefore, for malignant meningiomas, high-dose irradiation can facilitate cell invasiveness significantly. Downregulating the microRNA-221/222 level can reverse the radiation-induced cell invasiveness while enhancing the apoptosis-promoting and proliferation-inhibiting effects of radiation and promoting cell radiosensitivity.

A Logistic Regression Model for Detecting the Presence of Malignant Progression in Atypical Meningiomas.

OBJECTIVE: To develop a method to distinguish atypical meningiomas (AMs) with malignant progression (MP) from primary AMs without a clinical history. METHODS: The clinical, radiologic, and pathologic data of 33 previously Simpson grade I resected (if any) as well as no radiotherapy treated intracranial AMs between January 2008 and December 2015 were reviewed. Immunohistochemical staining for connexin 43 (Cx43) and Ki-67 was performed. Descriptive analysis and univariate and multivariate logistic regression analyses were used to explore independent predictors of MP. A multivariable logistic model was developed to estimate the risk of MP, and its diagnostic value was determined from a receiver operating characteristic curve. RESULTS: There were 11 AMs (33.3%) with histopathologically confirmed MP from benign meningiomas. The other 22 (66.7%) were initially diagnosed AMs with no histopathologically confirmed MP during a median 60.5 months (range, 42-126 months) of follow-up. Univariate and multivariate logistic analyses showed that irregular tumor shape (P = 0.010) and low Cx43 expression (P = 0.010) were independent predictors of the presence of MP, and the predicted probability was calculated by the following formula: P = 1/[1+exp.{1.218-(3.202×Shape)+(3.814×Cx43)}]. P > 0.5 for an irregularly shaped (score 1) AM with low Cx43 expression (score 0) indicated a high probability of MP. The sensitivity, specificity, positive predictive value, negative predictive value, and overall predictive accuracy were 63.6, 95.6, 87.5, 84.0, and 84.8%, respectively. CONCLUSIONS: Low Cx43 expression and irregular tumor shape were independent predictors of the presence of MP. The relevant logistic regression model was found to be effective in distinguishing MP-AMs from primary AMs.

[Preservation of pituitary stalk in the microsurgery of giant pituitary adenoma and its significance].

OBJECTIVE: To investigate and elucidate how to preserve the pituitary stalk in the microsurgery of giant pituitary adenoma (GPA) and its clinical significance. METHODS: 45 GPA patients, 23 males and 22 female; aged 40.8, including 12 cases of invasive pituitary adenoma (IPA) underwent craniotomy based on the respective preoperative neuroradiological imaging characteristics. The anatomical relationship between the pituitary stalk and tumor was recorded. The methods to protect the pituitary stalk were summarized. RESULTS: Total tumor excision was achieved in 25 patients (55.5%), near-total resection was done in 12 (26.7%), and subtotal resection in 8 (17.8%). During the surgical proceeding, the pituitary stalk was distinguished from the tumor and preserved well in all 33 cases with non-invasive giant pituitary adenoma. On the contrary, in the 12 cases of invasive giant pituitary adenoma (IPA) the pituitary stalk was visualized in only 7 cases. In the patients with visualized pituitary stalks 4 pituitary stalks were not identified very well. In most cases (91%) the pituitary stalks were located laterally (on the left or right side) or supero-posterior to the tumor, only a few were located anteriorly. In all 12 IPA patients 2 cases of postoperative hemorrhage occurred associated with remnant tumor and immediate hematoma evacuation was performed, however, one patient died due to hypothalamus injury. CONCLUSION: Pituitary stalk has various anatomical relationships to the entity of GPA; most are located lateral or supero-posterior to the tumor. However, the relationship between the stalk and tumor is not clear in IPA. Identifying and preserving the pituitary stalk well during surgical manipulation will be beneficial to get an excellent outcome.

Risk factors and the prognosis of sexual dysfunction in male patients with pituitary adenomas: a multivariate analysis.

The impact of sexual dysfunction (SD) is distressing to many male patients with pituitary adenomas which affect both physical and psychological health. The research explored to identify risk factors affecting sexual function and the prognosis of male patients with pituitary adenomas. Two hundred and fifty-four male patients, who aged between 18 and 60 (mean ± s.d.: 44.16 ± 10.14) years and diagnosed with pituitary adenomas, were retrospectively analyzed. One hundred and fifty-nine patients (62.6%) complained of SD prior to surgery. The mean International Index of Erectile Function (IIEF-5) in patients with giant adenomas was 16.13 ± 2.51, much smaller than those with microadenomas or macroadenomas (P < 0.05). All the patients showed significant improvement in terms of erectile dysfunction (ED) following surgery (P < 0.05). In addition, complete resection achieved a higher degree of SD relief than partial resection. The incidence of SD in functioning pituitary adenomas (FPAs) was much higher than that in nonfunctioning pituitary adenomas (NFPAs) (P < 0.05). In addition, compared with NFPAs, males with prolactinomas (82.8%) had the higher prevalence of SD and significantly improvement following surgical intervention (P < 0.05). An inverse relationship was identified between decreasing testosterone levels and increasing incidence of SD before surgery (P < 0.05). There was no significant difference between 6 months and 12 months after surgery in serum testosterone level (P > 0.05). Our results indicated that surgical therapy could be optimized for improvements in SD and that testosterone levels can be used as a sensitive indicator to predict the recovery rate of sexual function in patients with pituitary adenomas following surgery and the serum testosterone level will stay stable in 6 months after surgery.

Intratumoral Hemorrhage as an Unusual Manifestation of Intracranial Subependymoma.

BACKGROUND: Subependymoma is rare, and little is known about subependymoma with intratumoral hemorrhage. METHODS: A retrospective study of subependymoma was performed. Among 61 subependymomas, 4 cases of intratumoral hemorrhage were collected. All 4 cases were pathologically confirmed to be subependymoma and showed a benign character. RESULTS: After complete subependymoma resection, the 4 patients achieved favorable outcomes. Pathology showed that dilated thin-walled vessels and/or hyalinosis of the vessel walls existed in all 4 cases. CONCLUSIONS: The present series showed that subependymomas with hemorrhage and benign pathology are rare and that surgical treatment results in good prognosis. This series supports the hypothesis that the pathology of vascular degeneration may contribute to subependymoma hemorrhage.

Intracranial Mesenchymal Chondrosarcoma: Report of 16 Cases.

OBJECTIVES: Limited data regarding intracranial mesenchymal chondrosarcoma (MCS) are available. The goal of this study was to report the clinical characteristics, challenges in management, and poor outcomes of intracranial MCS. METHODS: Clinical data for 16 patients with MCS were reviewed retrospectively to evaluate their clinical characteristics, management, and outcomes. RESULTS: This study included 11 male and 5 female patients with a mean age of 22.9 ± 14.4 years. The most common presentations were headache (n = 10; 62.5%), followed by cranial deficits (n = 7; 43.6%). The radiologic spectrum for MCS was broad, and only 18.8% (3/16) of MCSs were correctly diagnosed preoperatively. Aggressive resection (including subtotal resection and gross total resection) and partial resection was performed in 62.5% (10/16) and 37.50% (6/16) of patients. With a median follow-up of 34 months (range, 10-78 months), 5 patients (31.3%) died and 8 patients (50%) developed tumor recurrence. The 1-, 3-, and 5-year rates of progression-free survival and overall survival were 86%, 53%, and 42% and 93%, 70%, and 56%, respectively. Although the differences were not significantly different, aggressive resection and the use of radiotherapy tended to improve the prognosis of the patients. CONCLUSIONS: Clinical characteristics of MCS are variable. The current management of intracranial MCS referring to conventional chondrosarcoma could not yield satisfactory outcomes. Further study is needed to identify the optimal treatments.

Primary Intracranial Angioleiomyomas as Rare, Nonmalignant, and Distinct Neoplastic Entities: A Series of 8 Cases and a Literature Review.

OBJECTIVE: Primary intracranial angioleiomyoma is a rare and distinct neoplasm. Only 29 cases have been reported previously, and we aimed to investigate the clinical and radiopathologic features of these lesions. METHODS: Medical records and radiographs of 8 patients (7 male and 1 female; mean age: 48.7 years) at our institution were reviewed retrospectively. Patient follow-up and a literature review were performed. RESULTS: The most common preoperative symptom was a visual defect (n = 2), followed by diplopia (n = 1) and abducens paralysis (n = 1). Three patients were asymptomatic. The parasellar area (particularly the cavernous sinus) was the predilection site (n = 4; 50.0%). Radiographically, all lesions were solid without cystic degeneration. All lesions appeared with T1 hypointensity and T2 hyperintensity, and they were gradually heterogeneously enhanced after the administration of gadolinium. Complete resection was achieved in 7 patients (87.5%) without recurrence after 26.8 months of follow-up. Mitosis was rarely observed, and the Ki-67 labeling index was less than 1%; pathologically, the cavernous type was the most common. CONCLUSIONS: Primary intracranial angioleiomyomas were prevalent in middle-aged men, and they usually involved the cavernous sinus and were frequently pathologically identified as the cavernous type. Preoperative symptoms varied depending on lesion location. The preoperative diagnosis of primary intracranial angioleiomyomas is difficult without pathology. Digital subtraction angiography and preoperative embolization are useful for differential diagnosis and surgery. Given the indolent biology of these tumors, a favorable outcome can be achieved using total resection without recurrence. A larger sample size with long-term follow-up is needed to verify our findings.

Intraoperative facial motor evoked potentials monitoring with transcranial electrical stimulation for preservation of facial nerve function in patients with large acoustic neuroma.

BACKGROUND: Although various monitoring techniques have been used routinely in the treatment of the lesions in the skull base, iatrogenic facial paresis or paralysis remains a significant clinical problem. The aim of this study was to investigate the effect of intraoperative facial motor evoked potentials monitoring with transcranial electrical stimulation on preservation of facial nerve function. METHOD: From January to November 2005, 19 patients with large acoustic neuroma were treated using intraoperative facial motor evoked potentials monitoring with transcranial electrical stimulation (TCEMEP) for preservation of facial nerve function. The relationship between the decrease of MEP amplitude after tumor removal and the postoperative function of the facial nerve was analyzed. RESULTS: MEP amplitude decreased more than 75% in 11 patients, of which 6 presented significant facial paralysis (H-B grade 3), and 5 had mild facial paralysis (H-B grade 2). In the other 8 patients, whose MEP amplitude decreased less than 75%, 1 experienced significant facial paralysis, 5 had mild facial paralysis, and 2 were normal. CONCLUSIONS: Intraoperative TCEMEP can be used to predict postoperative function of the facial nerve. The decreased MEP amplitude above 75 % is an alarm point for possible severe facial paralysis.

[Factors influencing the survival of patients with skull base chordoma].

OBJECTIVE: To investigate the factors influencing the survival of patients with skull base chordoma. METHODS: The clinical data of 79 patients with skull base chordoma, with a male/female ratio of 1.3:1, who received operations in Tiantan Hospital between May 1993 and June 2005 were selected. Thirteen factors, including gender, age, main symptoms, positive signs, bulk of the tumor, having received operation or radiotherapy before admission, grouping and staging of the tumor's location, and texture, adherence, pathological and resection grouping of the lesion, underwent Kaplan-Meier single factor analysis, Cox regression, and t-test. RESULTS: Kaplan-Meier single factor analysis displayed that having received operation or radiotherapy before admission, adherence, pathological and resection groupings of the lesion were the risk factors of the patients' life span (all P < 0.01). Cox multiple factor analysis showed that the all of the above factors except adherence grouping of the lesion had statistical significance on the patients' life span (all P < 0.01). CONCLUSION: Having received operation or radiotherapy before admission, adherence, pathological and resection groupings of the lesion influence the prognosis of skull base chordoma.

[A long term follow-up study of the skull base chordomas].

OBJECTIVE: To investigate the prognostic features of the skull base chordomas treated with neurosurgical operations. METHODS: One hundred and six patients of skull base chordomas were enrolled by means of telephone, letter and out-patient recheck who presented between May 1993 and June 2005. They were scored by Karnofsky Performance Scale (KPS) during admission respectively, before period of discharge and follow-up. SPSS Life-table method was used to calculate the recurrent rates and survival rates. RESULTS: Seventy-nine patients were followed for 10-158 months. The average period was 63.9 months. Survival rates of 1, 3, 5 and 10 year were 87.2%, 79.4%, 67.6% and 59.5%, meanwhile recurrent rates of 1, 3, 5 and 10 years were 19.1%, 34.7%, 52.9% and 88.3% respectively. The mean KPS on admission, before discharge and follow-up were 71.0, 72.5 and 67.1 respectively, which demonstrated the significant differences between the before discharge item and the follow-up. CONCLUSIONS: The prognosis of the skull base chordomas was poor. The recurrent rate was ascending year by year, meanwhile the survival rate was descending and 8 years later the tendency became gently. Neurosurgical treatments can improve majority long-term qualities, so they should be viewed as the first treatment choice.

Intra- and Extramedullary Dumbbell-Shaped Schwannoma of the Medulla Oblongata: A Case Report and Review of the Literature.

BACKGROUND: Brainstem intramedullary schwannomas (ISs) are extremely rare. Various theories have been suggested to explain its origin. It was first speculated that ISs arise from the region where the nerve roots lose their sheaths on penetrating the pia mater. Later, it was further predicted that ISs would contain both intra- and extramedullary parts and would be shaped like a dumbbell. However, no cases reported previously can support this assumption adequately. CASE DESCRIPTION: A 40-year-old woman presented with constant cervical pain, accompanied by progressive weakness of upper extremities and glove distribution numbness. Magnetic resonance imaging of the brain revealed a rare intra- and extramedullary dumbbell-shaped lesion of the medulla oblongata, which was partially removed via a midline suboccipital craniectomy. Histologic and immunohistochemical examinations confirmed the diagnosis of schwannoma. Routine imaging performed 20 months after the initial resection revealed a regrowth of the intramedullary part, which was subsequently partially removed through a far-lateral approach, with symptoms alleviated. At 2-year follow-up, there continued to be no radiologic or clinical evidence of regrowth. CONCLUSIONS: To date and to our knowledge, there are only 16 reported cases of brainstem ISs, none of which contained both intra- and extramedullary components. We believe this is the first report of dumbbell schwannoma of the medulla oblongata with adequate radiologic evidence. The relevant literature is reviewed, and an assumption has been proposed that dumbbell or surfacing ISs arising near entry zones of sensory nerves, mixed cranial nerves, or ventral root may originate from the aberrant Schwann cells.