Ventriculomegaly and postoperative lateral/third ventricular blood as predictors of cerebrospinal fluid diversion following posterior fossa tumor resection

Validating the modified Canadian Preoperative Prediction Rule for Hydrocephalus for accurate hydrocephalus prediction in a statewide pediatric brain tumor cohort

PURPOSE

The modified Canadian Preoperative Prediction Rule for Hydrocephalus (mCPPRH) was developed to predict the need for permanent CSF diversion in children with posterior fossa tumors (PFT). This study aimed to externally validate the mCPPRH in a cohort of 113 pediatric patients with PFTs.

METHODS

We conducted a retrospective analysis, calculating the mCPPRH score for each patient and performing receiver operating characteristic (ROC) curve analysis to assess the tool's discriminative ability. Sensitivity, specificity, predictive values, and likelihood ratios were calculated using a cutoff score of ≥ 5. Multivariable logistic regression with bidirectional stepwise selection was used to evaluate individual components of the score. The mCPPRH components were modified and the performance of adjusted tools was compared to the original.

RESULTS

Of the 113 patients, 35 (31.0%) required permanent CSF diversion. The mCPPRH demonstrated acceptable discriminative ability (AUC = 0.701, 95% CI 0.608-0.795, p < 0.0003). Sensitivity was 34.1%, specificity 89.7%, positive predictive value 60%, and negative predictive value 75.3%. Initial regression identified no significant predictors. In stepwise regression, moderate-severe hydrocephalus independently predicted permanent CSF diversion (OR 6.37, 95% CI 1.71-41.55, p = 0.02). Increasing the age cutoff to < 5 years, removing tumor diagnosis, and modifying hydrocephalus weighting improved performance (AUC = 0.768, sensitivity 71.4%, specificity 75.6%).

CONCLUSIONS

The mCPPRH demonstrates acceptable discriminative ability (AUC 0.701) in our cohort, with particular utility in identifying low-risk patients. However, its poor sensitivity (34.1%) and variable predictor performance suggest that additional clinical factors should be considered for treatment planning, particularly in higher-risk cases. Further modification of mCPPRH components is suggested to improve its utility.

A nomogram for predicting post-operative hydrocephalus in children with medulloblastoma

Post-operative hydrocephalus is common among children with medulloblastoma after initial tumor resection. This study aimed to establish a novel model for predicting the development of post-operative hydrocephalus in children with medulloblastoma. Only pediatric patients who received initial medulloblastoma resection at Beijing Tiantan Hospital between January 2018 and May 2021 were included in this study. The potential risk factors associated with post-operative hydrocephalus were identified based on multivariate logistic regression and the nomogram. Receiver operating characteristic (ROC) curve were used to evaluate the performance of the nomogram model based on an independent cohort of medulloblastoma patients who underwent surgery from June 2021 to March 2022. A total of 105 patients were included in the primary cohort. Superior invasion (P = 0.007), caudal invasion (P = 0.025), and intraventricular blood ≥ 5 mm (P = 0.045) were significantly related to the development of post-operative hydrocephalus and thus were assembled into the nomogram model. The model accurately predicted post-operative hydrocephalus based on the calibration curve. The area under the ROC curves for the primary and validation cohorts was 0.849 and 0.855, respectively. In total, the nomogram we developed may aid clinicians in assessing the potential risk of pediatric patients with MB developing post-operative hydrocephalus, especially those who would otherwise not have received a diversionary procedure at presentation.

Incidence and Risk Factors for Necessitating Cerebrospinal Fluid Diversion Following Medulloblastoma Surgery in Children

BACKGROUND

There are insufficient data on pediatric patients with medulloblastoma who require cerebrospinal fluid (CSF) diversion following resection. Therefore, this study aimed to determine the incidence and the characteristics associated with it in this subset of patients.

METHODS

We conducted a single-center, retrospective, observational cohort study of patients aged 18 years or less who underwent medulloblastoma resection at our department between 2010 and 2021. The primary outcome was the incidence of CSF diversion surgery required after resection. Participant demographics, tumor biology, and interventions were analyzed using univariate- and multivariate-adjusted models.

RESULTS

Of the 183 patients admitted to our department, 131 (71.6%) participated in this study. The incidence of permanent CSF diversion was 26.0% (95% confidence interval [CI]: 18.7 to 34.3). Factors independently associated with requirement of permanent CSF diversion were medulloblastoma volume >46.4 cm³ (odds ratio [OR]: 2.919, 95% CI: 1.191 to 7.156) and CSF channel invasion (OR: 2.849, 95% CI: 1.142 to 7.102). The duration of manifestation may be a covariate of tumor volume with increased risk of requirement for permanent CSF diversion (OR: 1.006, 95% CI: 1.000 to 1.013), and tumor volume may be a predictor in patients who underwent subtotal resection (OR: 4.900, 95% CI: 0.992 to 24.208, P = 0.05). Finally, patients who required permanent CSF diversion were divided according to medulloblastoma molecular subgroups, and no significant differences were found.

CONCLUSION

We report major predictive factors for permanent CSF diversion surgery in patients with medulloblastoma. Our study suggests that the presence of postresection hydrocephalus is not high enough to warrant permanent, prophylactic CSF diversion in all patients.

Contribution of tumor characteristics and surgery-related factors to symptomatic hydrocephalus after posterior fossa tumor resection: a single-institution experience

OBJECTIVE

Pediatric patients are at risk of persistent hydrocephalus after posterior fossa tumor resection. The relationship between surgery-related factors and postoperative symptomatic hydrocephalus has not been elucidated. The objective of this study was to analyze features influencing postoperative hydrocephalus in Chinese children.

METHODS

The authors retrospectively evaluated 197 patients younger than 15 years of age who underwent posterior fossa tumor resection at their institution from January 2015 to June 2021. The outcome was whether children underwent CSF diversion within 6 months of resection. Preoperative characteristics, surgery-related factors, and postoperative features were included to identify independent prognosticators. A new logistic model containing independent prognosticators was developed and compared with the modified Canadian Preoperative Prediction Rule for Hydrocephalus (mCPPRH).

RESULTS

In this study, 30 patients (15.2%) underwent CSF diversion within 6 months after tumor resection. Tumor location and consistency, intracranial or spinal tumor metastasis determined by perioperative cerebral and spinal MRI, intraoperative blood loss, ventricular blood as determined on postoperative CT, and pathology were statistically significant variables in the univariate analysis. The only two independent predictors of postoperative symptomatic hydrocephalus were tumor metastasis (OR 3.463, 95% CI 1.137-10.549; p = 0.029) and postoperative ventricular blood (OR 4.212, 95% CI 1.595-11.122; p = 0.004). The final logistic model comprising tumor metastasis and postoperative ventricular blood was found to have better discrimination than the mCPPRH.

CONCLUSIONS

Tumor characteristics and surgery-related features were associated with postoperative symptomatic hydrocephalus. Tumor metastasis and postoperative ventricular blood were found to be important prognosticators of persistent hydrocephalus.