Does Meningioma Volume Correlate With Clinical Disease Manifestation Irrespective of Histopathologic Tumor Grade?:

Automated volumetry of meningiomas in contrast-enhanced T1-Weighted MRI using deep learning

BACKGROUND

Meningiomas are among the most common intracranial tumors. In these tumors, volumetric assessment is not only important for planning therapeutic intervention but also for follow-up examination.However, a highly accurate automated volumetric method for meningiomas using single-modality magnetic resonance imaging (MRI) has not yet been reported. Here, we aimed to develop a deep learning-based automated volumetry method for meningiomas in MRI and investigate its accuracy and potential clinical applications.

METHODS

For deep learning, we used MRI images of patients with meningioma who were referred to Osaka University Hospital between January 2007 and October 2020. Imaging data of eligible patients were divided into three non-overlapping groups: training, validation, and testing. The model was trained and tested using the leave-oneout cross-validation method. Dice index (DI) and root mean squared percentage error (RMSPE) were measured to evaluate the model accuracy. Result: A total of 178 patients (64.6 ± 12.3 years [standard deviation]; 147 women) were evaluated. Comparison of the deep learning model and manual segmentation revealed a mean DI of 0.923 ± 0.051 for tumor lesions. For total tumor volume, RMSPE was 9.5 ± 1.2%, and Mann-Whitney U test did not show a significant difference between manual and algorithm-based measurement of the tumor volume (p = 0.96).

CONCLUSION

The automatic tumor volumetry algorithm developed in this study provides a potential volume-based imaging biomarker for tumor evaluation in the field of neuroradiological imaging, which will contribute to the optimization and personalization of treatment for central nervous system tumors in the near future.

Growth risk classification and typical growth speed of convexity, parasagittal, and falx meningiomas: a retrospective cohort study

OBJECTIVE

Meningiomas are the most common primary intracranial tumors, and their clinical and biological characteristics vary by location. Convexity, parasagittal, and falx meningiomas account for approximately 50%-65% of intracranial meningiomas. Focusing only on these locations, the aim of this study was to determine the typical speed of tumor growth, to assess the growth risk, and to show the possible tumor volume that many lesions can reach after 5 years.

METHODS

Patients with radiologically suspected convexity, parasagittal, or falx meningiomas at the authors' institution were studied retrospectively. The relative growth rate (RGR) and annual volume change (AVC) were calculated from MRI at more than 3-month intervals. Based on sex, age, and signal intensity on T2-weighted MRI, the cases were classified into three groups: extremely high-growth, high-growth, and low-growth groups.

RESULTS

The data of 313 cases were analyzed. The median RGR and AVC for this entire cohort were 6.1% (interquartile range [IQR] 2.4%-16.0%) and 0.20 (IQR 0.04-1.18) cm3/year, respectively. There were significant differences in sex (p = 0.018) and T2-weighted MRI signal intensity (p < 0.001) for RGR, and T2-weighted MRI signal intensity (p < 0.001), tumor location (p = 0.025), and initial tumor volume (p < 0.001) for AVC. The median RGR and AVC were 17.5% (IQR 8.3%-44.1%) and 1.05 (IQR 0.18-3.53) cm3/year, 8.2% (IQR 2.9%-18.6%) and 0.33 (IQR 0.06-1.66) cm3/year, and 3.4% (IQR 1.2%-5.8%) and 0.04 (IQR 0.02-0.21) cm3/year for the extremely high-growth, high-growth, and low-growth groups, respectively, with a significant difference among the groups (p < 0.001). A 2.24-times, or 5.24 cm3, increase in tumor volume over 5 years was typical in the extremely high-growth group, whereas the low-growth group showed little change in tumor volume even over a 5-year follow-up period.

CONCLUSIONS

For the first time, the typical speed of tumor growth was calculated, focusing only on patients with convexity, parasagittal, and falx meningiomas. In addition, the possible tumor volume that many lesions in these locations can reach after 5 years was shown based on objective indicators. These results may allow clinicians to easily detect lesions that require frequent follow-up or early treatment by determining whether they deviate from the typical range of the growth rate, similar to a growth chart for children.

How Much Tumor Volume Is Responsible for Development of Clinical Symptoms in Patients With Convexity, Parasagittal, and Falx Meningiomas?

Purpose: Meningiomas are the most common primary intracranial neoplasms and clinical symptom appearance depends on their volume and location. This study aimed to identify factors that influence clinical symptoms and to determine a specific threshold tumor volume for the prediction of symptomatic progression in patients with convexity, parasagittal, and falx meningiomas.

Materials and Methods: We retrospectively studied patients with radiologically suspected convexity, parasagittal, or falx meningiomas at our institution.

Results: The data of three hundred thirty-three patients were analyzed. We further divided patients into two groups based on clinical symptoms: an asymptomatic group (250 cases) and a symptomatic group (83 cases). Univariate analysis revealed significant differences between the groups in terms of sex (p = 0.002), age at the time of volumetric analysis (p < 0.001), hyperintense lesions on T2-weighted images (p = 0.029), peritumoral edema (p < 0.001), maximum tumor diameter (p < 0.001), and tumor volume (p < 0.001). Further multivariate analysis revealed significant differences between the groups in terms of age at the time of volumetric analysis (p = 0.002), peritumoral edema (p < 0.001), and tumor volume (p < 0.001). The receiver operating characteristic curve revealed a threshold tumor volume of 21.1 ml for predicting whether a patient would develop symptoms (sensitivity 0.843, specificity 0.880, an area under the curve 0.919 [95% confidence interval: 0.887–0.951]).

Conclusion: We identified factors predictive of clinical symptoms in patients with convexity, parasagittal, and falx meningiomas and determined the first-ever threshold tumor volume for predicting symptomatic progression in such patients.

Relapse of Psychosis Status Post Meningioma Resection

A 53-year-old Caucasian female with a previous psychiatric history of bipolar I disorder and attention deficit hyperactivity disorder presented to the emergency department after endorsing 10-11 months of auditory and visual hallucinations, persecutory delusions, depression, anosmia, weakness of lower extremities, and headache. The patient described her auditory hallucinations as non-commanding voices talking to her about her family, her visual hallucinations as seeing "shadows and shapes," and her paranoid delusions as people coming after her. The patient had sustained a fall a week and a half earlier, requiring eight sutures to her posterior scalp. Her MRI of the brain showed a well-circumscribed 3.5 x 4.7 x 3.2 cm mass in the floor of the anterior cranial fossa. Computer tomography of the brain showed a 4.5 cm mass near the anterior interhemispheric fissure and edema in the right frontal cortex. Meningioma resection resulted in the cessation of hallucinations and delusions for one week. However, the patient was brought back to the emergency department because her auditory hallucinations and delusions returned. This case report demonstrates residual psychosis, even after frontal meningioma resection.

Anatomical and volumetric analysis of fibro-osseous lesions of the craniofacial skeleton

PURPOSE

Our study aimed to provide volumetric data relating to fibro-osseous lesions of the craniofacial skeleton, in order to highlight risk factors due to the different entities, and to guide clinical decisions for jeopardized patients.

METHODS

Volumetric measurements of osteomas and ossifying fibromas were performed by applying the open-source software ITK-Snap to cone-beam computed tomography images. DICOM datasets were imported, identified, and delineated using semiautomatic segmentation; this was then verified using manual segmentation. The volumes of the lesions were computed automatically in cubic millimeters using the program. For statistical investigations, descriptive statistics and independent Student t-tests were performed. Additionally, Pearson's correlation was applied as a bivariate analysis. Values of p < 0.05 were considered significant.

RESULTS

45 patients (11 male and 34 female) were included in this study. The mean volumes were 10.02 ± 18.79 cm³ for osteomas and 4.80 ± 5.71 cm³ for ossifying fibromas (p = 0.016). Males (12.81 ± 20.38 cm³) presented significantly larger volumes than females (5.43 ± 10.32 cm³) (p = 0.042). With regard to shape, morphology, and affection of surrounding anatomical structures, irregular shape (p = 0.001; p = 0.037), multilocular morphology (p = 0.001; p = 0.037), nerve affection (p = 0.001; p = 0.002), tooth affection (p = 0.001; p = 0.594), cortical bone exceedance (p = 0.033; p = 0.001), and clinically visible symptoms (p = 0.004; p = 0.001) were statistically significantly associated with a larger volume of both entities.

CONCLUSION

Volumetric analysis revealed that osteomas significantly exceeded the mean size of ossifying fibromas, supporting the argument that special attention should be paid to this entity. In cases of difficult histopathological examination, lesions with irregular shape, multilocular morphology, nerve and tooth affection, cortical bone exceedance, and clinically visible symptoms should be considered for close clinico-radiological follow-up, irrespective of the entity.

Dynamic Maxillary Sinus Changes of Facial Vascularized Composite Allotransplants

SUMMARY

Skin is one of the target tissues of rejection in face transplants and, because of its easy accessibility, has become the gold standard in the diagnosis of rejection. The allograft contains deeper tissues where rejection can occur, but samples cannot be obtained because of difficult access. Deep tissue changes were monitored on computed tomographic scans of the midface in six face transplant recipients with the help of image segmentation. The maxillary sinus was identified as a dynamic anatomical compartment. Observed changes in volume of the aeration relative to the opacification (aeration coefficient) of the maxillary sinus were quantified with the help of image segmentation. Changes in the aeration coefficient as a surrogate of mucosal swelling were quantified and related to time, treatment, and skin rejection grade. Lower aeration coefficients were found only in patients with transplanted maxillary sinus mucosa. Pathologic changes were not observed in face transplant recipients with a native maxillary sinus. The data show that the aeration coefficient was significantly lower at the time of biopsy-proven allograft rejection. Neither mechanical, nor infectious, nor medication side effects sufficiently explain the findings presented herein. The authors' findings are important to consider for clinical management of face transplant patients who receive parts of the sinonasal tract. The authors identify a potential radiologic biomarker of deep tissue allograft rejection. In the future, the proposed methodology might prove useful in monitoring deeper dynamic tissue changes in vascularized composite allografts and might help in designing patient-specific, individualized treatment strategies.

Anatomical and Volumetric Analysis of the Sphenoid Sinus by Semiautomatic Segmentation of Cone Beam Computed Tomography

This investigation was performed to analyze and evaluate anatomical and volumetric data of the sphenoid sinus by semiautomatic segmentation of cone beam computed tomography (CBCT) datasets.This analysis was carried out on cone beam computed tomography images of 100 patients. By using the discretionary software "ITK-Snap", the volumetric investigation of 197 sphenoid sinuses was conducted. The statistical analyses were carried out by using the paired and independent Student t-test. In addition, the Pearsons chi-square test was performed. P values P < 0.05 were considered significant.The volumetric mean was 4.438 ± 2.434 cm for the right and 4.809 ± 3.000 for the left side. Results did not indicate statistically significant differences according to the side, irrespective of gender (P > 0.05). The further investigation of differences between male and female patients did assess significant results (P < 0.05), males (10.477 ± 3.851 cm) present a larger total sinus volume than females (8.219 ± 3.574 cm). In accordance to patients' age (median 54 years), smaller volumes were related to younger patients and larger volumes to older ones. But, no statistically significant results in accordance to age could be detected (χ = 1.258; P > 0.05).Endoscopic sinus surgery of the vulnerable and intricate anatomy of the sphenoid sinus requires an explicit knowledge and orientation about the anatomical variations such as septums and volumetric capacity. Concerning this matter, semiautomatic segmentation of CBCT images can aid the surgeon in preoperative planning. Our investigation shows that a small sinus volume, that is, affecting female patients and a complex sinus anatomy by the occurrence of a septum, especially located close to neurovascular structures could essentially aggravate endoscopic sphenoid sinus surgery. In this regard, volumetric analysis of the sphenoid sinus by CBCT images can provide presurgical information and facilitates an individualized treatment.