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European Radiology Nov 2023Surgical planning of vestibular schwannoma surgery would benefit greatly from a robust method of delineating the facial-vestibulocochlear nerve complex with respect to...
OBJECTIVES
Surgical planning of vestibular schwannoma surgery would benefit greatly from a robust method of delineating the facial-vestibulocochlear nerve complex with respect to the tumour. This study aimed to optimise a multi-shell readout-segmented diffusion-weighted imaging (rs-DWI) protocol and develop a novel post-processing pipeline to delineate the facial-vestibulocochlear complex within the skull base region, evaluating its accuracy intraoperatively using neuronavigation and tracked electrophysiological recordings.
METHODS
In a prospective study of five healthy volunteers and five patients who underwent vestibular schwannoma surgery, rs-DWI was performed and colour tissue maps (CTM) and probabilistic tractography of the cranial nerves were generated. In patients, the average symmetric surface distance (ASSD) and 95% Hausdorff distance (HD-95) were calculated with reference to the neuroradiologist-approved facial nerve segmentation. The accuracy of patient results was assessed intraoperatively using neuronavigation and tracked electrophysiological recordings.
RESULTS
Using CTM alone, the facial-vestibulocochlear complex of healthy volunteer subjects was visualised on 9/10 sides. CTM were generated in all 5 patients with vestibular schwannoma enabling the facial nerve to be accurately identified preoperatively. The mean ASSD between the annotators' two segmentations was 1.11 mm (SD 0.40) and the mean HD-95 was 4.62 mm (SD 1.78). The median distance from the nerve segmentation to a positive stimulation point was 1.21 mm (IQR 0.81-3.27 mm) and 2.03 mm (IQR 0.99-3.84 mm) for the two annotators, respectively.
CONCLUSIONS
rs-DWI may be used to acquire dMRI data of the cranial nerves within the posterior fossa.
CLINICAL RELEVANCE STATEMENT
Readout-segmented diffusion-weighted imaging and colour tissue mapping provide 1-2 mm spatially accurate imaging of the facial-vestibulocochlear nerve complex, enabling accurate preoperative localisation of the facial nerve. This study evaluated the technique in 5 healthy volunteers and 5 patients with vestibular schwannoma.
KEY POINTS
• Readout-segmented diffusion-weighted imaging (rs-DWI) with colour tissue mapping (CTM) visualised the facial-vestibulocochlear nerve complex on 9/10 sides in 5 healthy volunteer subjects. • Using rs-DWI and CTM, the facial nerve was visualised in all 5 patients with vestibular schwannoma and within 1.21-2.03 mm of the nerve's true intraoperative location. • Reproducible results were obtained on different scanners.
Topics: Humans; Neuroma, Acoustic; Prospective Studies; Diffusion Tensor Imaging; Diffusion Magnetic Resonance Imaging; Facial Nerve; Vestibulocochlear Nerve
PubMed: 37328641
DOI: 10.1007/s00330-023-09736-4 -
Ear, Nose, & Throat Journal Mar 2024This study aimed to investigate the perilymph metabolism by analyzing the 3D real IR MR findings in acoustic neuroma (AN) after intravenous administration of gadolinium...
OBJECTIVES
This study aimed to investigate the perilymph metabolism by analyzing the 3D real IR MR findings in acoustic neuroma (AN) after intravenous administration of gadolinium (Gd).
METHODS
Eleven patients (6 men and 5 women) diagnosed with AN were included, and 3D real IR MRI was performed 4 hours after intravenous Gd injection. The signal intensity and details of inner ear, tumor, and internal auditory canal (IAC) by MRI were analyzed.
RESULTS
Four patients had tumors confined to the IAC, and 5 had tumors that extended to the cerebellopontine angle cistern. The signal intensity of the cochlea, vestibule, and IAC fundus was conspicuously enhanced in 3D real IR images than the control side. One patient had a tumor in the cochlea, in which the signal intensity of the semicircular canal and vestibule was increased. One patient had an intravestibular tumor in which the signal intensity of the semicircular canal was increased and the cochlea had endolymphatic hydrops in the affected ear.
CONCLUSIONS
The synchronously increased signal intensity in the inner ear and IAC may indicate that IAC may serve as a channel for removal of the perilymph in the inner ear; the blockage by the tumor may have changed the hydrodynamics of the perilymph to cause a longer retention of Gd in the inner ear.
Topics: Male; Humans; Female; Perilymph; Neuroma, Acoustic; Gadolinium DTPA; Contrast Media; Vestibule, Labyrinth; Magnetic Resonance Imaging
PubMed: 34560831
DOI: 10.1177/01455613211047124 -
Journal of Applied Clinical Medical... Oct 2023To investigate the impact of MRI patient-specific geometrical distortion (PSD) on the quality of Gamma Knife stereotactic radiosurgery (GK-SRS) plans of the vestibular...
Patient-specific geometrical distortion corrections of MRI images improve dosimetric planning accuracy of vestibular schwannoma treated with gamma knife stereotactic radiosurgery.
PURPOSE
To investigate the impact of MRI patient-specific geometrical distortion (PSD) on the quality of Gamma Knife stereotactic radiosurgery (GK-SRS) plans of the vestibular schwannoma (VS) tumors.
METHODS AND MATERIALS
Three open access datasets including the MPI-Leipzig Mind-Brain-Body (318 patients), the slow event-related fMRI designs dataset (62 patients), and the VS dataset (242 patients) were used. We used first two datasets to train a 3D convolution network to predict the distortion map of third dataset that were then used to calculate and correct the PSD. GK-SRS plans of VS dataset were used to evaluate dose distribution of PSD-corrected MRI images. GK-SRS prescription dose of VS cases was 12 Gy. Geometric and dosimetric discrepancies were assessed between the dose distributions and contours before and after the PSD corrections. Geometry indices were center of the contours, Dice coefficient (DC), Hausdorff distance (HD), and dosimetric indices were , , , and doses, target coverage (TC), Paddick's conformity index (PCI), Paddick's gradient index (GI), and homogeneity index (HI).
RESULTS
Geometric distortions of about 1.2 mm were observed at the air-tissue interfaces at the air canal and nasal cavity borders. Average center of the targets was significantly distorted along the frequency encoding direction after the PSD-correction. Average DC and HD metrics were 0.90 and 2.13 mm. Average , and in Gy significantly increased after PSD correction from 16.85 to 17.25, 12.30 to 12.77, and from 8.98 to 9.92. did not significantly change after the correction. Average TC and PCI significantly increased from 0.97 to 0.98, and 0.94 to 0.96. Average GI decreased significantly from 2.24 to 2.15 after PSD correction. However, HI did not significantly change after the correction.
CONCLUSION
The proposed method could predict and correct the PSD that indicates the importance of PSD correction before GK-SRS plans of the VS patients.
Topics: Humans; Radiosurgery; Neuroma, Acoustic; Radiometry; Brain; Magnetic Resonance Imaging; Radiotherapy Planning, Computer-Assisted; Radiotherapy Dosage
PubMed: 37345614
DOI: 10.1002/acm2.14072 -
Diagnostics (Basel, Switzerland) Aug 2023Inflammatory myofibroblastic tumor (IMT) stands as a rare neoplasm, initially documented by Bahadori and Liebow in 1973; however, its biological behavior and underlying...
Inflammatory myofibroblastic tumor (IMT) stands as a rare neoplasm, initially documented by Bahadori and Liebow in 1973; however, its biological behavior and underlying pathogenesis continue to elude comprehensive understanding. Throughout the years, this tumor has been designated by various alternative names, including pseudosarcomatoid myofibroblastoma, fibromyxoid transformation, and plasma cell granuloma among others. In 2002, the World Health Organization (WHO) officially classified it as a soft tissue tumor and designated it as IMT. While IMT primarily manifests in the lungs, the common clinical symptoms encompass anemia, low-grade fever, limb weakness, and chest pain. The mesentery, omentum, and retroperitoneum are subsequent sites of occurrence with intracranial involvement being exceedingly rare. Due to the absence of specific clinical symptoms and characteristic radiographic features, diagnosing intracranial inflammatory myofibroblastic tumor (IIMT) remains challenging. Successful instances of pharmacological treatment for IIMT indicate that surgery may not be the sole therapeutic recourse, thus underscoring the imperative of an accurate diagnosis and apt treatment selection to improve patient outcomes.
PubMed: 37685263
DOI: 10.3390/diagnostics13172725 -
Ear, Nose, & Throat Journal Aug 2023Acoustic neuromas are the most common tumor of the cerebellopontine angle that are associated with a number of symptoms that negatively impact a patient's quality of...
Acoustic neuromas are the most common tumor of the cerebellopontine angle that are associated with a number of symptoms that negatively impact a patient's quality of life. While the mainstay of treatment for these benign tumors remains microsurgical resection, there is limited research exploring how certain modifiable risk factors (MRFs) may affect the perioperative course. The purpose of this study was to investigate how MRFs including malnutrition, obesity, dyslipidemia, uncontrolled hypertension, and smoking may affect postoperative rates of readmission and nonroutine discharges. We utilized the 2016 and 2017 Healthcare Cost and Utilization Project Nationwide Readmissions Database. MRFs were queried using appropriate International Classification of Diseases, Tenth Revision (ICD-10) coding for categories including malnutrition, obesity, dyslipidemia, smoking, alcohol, and hypertension. The statistical analysis was done using RStudio (Version 1.3.959). Chi-squared tests were done to evaluate differences between categorical variables. The Mann-Whitney testing was utilized to evaluate for statistically significant differences in continuous data. The "Epitools" package was used to develop logistic regression models for postoperative complications and post hoc receiver operating characteristic curves were developed. Pertaining to nonroutine discharge, predictive models using malnutrition outperformed all other MRFs as well as those with no MRFs ( < .05). In the case of readmission, models using malnutrition outperformed those of obesity and smoking ( < .05). Again, an increase in predictive power is seen in models using dyslipidemia when compared to obesity, smoking, or uncontrolled hypertension. Lastly, models using no MRFs outperformed those of obesity, smoking, and uncontrolled hypertension ( < .05). This is the first study of its kind to evaluate the role of MRFs in those undergoing surgical resection of their acoustic neuroma. We concluded that certain MRFs may play a role in complicating a patient's perioperative surgical course.
PubMed: 37605484
DOI: 10.1177/01455613231191020 -
Journal of Applied Clinical Medical... Dec 2023Two optimization algorithms VOLO™ and sequential optimization algorithm (SEQU) are compared in the Precision® treatment planning system from Accuray® for...
INTRODUCTION
Two optimization algorithms VOLO™ and sequential optimization algorithm (SEQU) are compared in the Precision® treatment planning system from Accuray® for stereotactic radiosurgery and stereotactic body radiotherapy (SBRT) treatment plans. The aim is to compare the two algorithms to assess if VOLO™ is better of SEQU in certain treatment site.
MATERIALS AND METHODS
Sixty clinical treatment cases were compared. Entities include Acoustic neuroma (AN), lung metastases, and liver metastases. In each entity, 10 SEQU and 10 VOLO™ treatment plans were optimized. The Ray-Tracing calculation algorithm was used for all treatment plans and the treatments were planned exclusively with fixed cones (5-50 mm). The number of nodes, beams, total MU, and treatment time were compared. Conformity index (CI), new conformity index (nCI), homogeneity index (HI), gradient index (GI), and target coverage were examined for agreement. D , D , D , D100%, D98%, and D2% dose in the target volume as well as exposure to organs at risk was checked. To determine peripheral doses, the isodose volumes from V10% to V98% were evaluated.
RESULTS
AN treatment plans showed significant differences for the number of nodes, beams, total MU, treatment time, D98%, D100% for the target volume, and the doses for all organs at risk. VOLO™ achieved better results on average. Total MU, treatment time, coverage, and D98% are significantly better for VOLO™ for lung metastases. For liver metastases, a significant reduction in number of nodes, total MU, and treatment time was observed for VOLO™ plans. The mean target coverage increased slightly with VOLO™, while the mean CI deteriorated slightly. The averages of D , D , D98%, D100%, and V80% resulted in a significant increase for VOLO™.
CONCLUSION
The results of the present study indicate that VOLO™ should be used in place of SEQU as a standard for AN cases moving forward. Despite the lack of significance in the lung and liver cases, VOLO™ optimization is recommended because OAR sparing was similar, but coverage, D , and D were increased, and thus better tumor control can be expected.
Topics: Humans; Neuroma, Acoustic; Radiotherapy Planning, Computer-Assisted; Radiotherapy Dosage; Radiotherapy, Intensity-Modulated; Retrospective Studies; Lung Neoplasms; Radiosurgery; Liver Neoplasms; Algorithms; Organs at Risk
PubMed: 37672349
DOI: 10.1002/acm2.14144 -
International Archives of... Jul 2023The surgical management of jugulotympanic paragangliomas has remained challenging. They are the second most common type of tumor of the temporal bone after acoustic...
The surgical management of jugulotympanic paragangliomas has remained challenging. They are the second most common type of tumor of the temporal bone after acoustic neuroma. It has been noticed by the authors that the jugulotympanic paragangliomas may have extensions to the epitympanum and aditus in addition to the mesotympanum and hypotympanum. The modified technique could be an alternative to the conventional facial recess technique for complete removal of the tumors. To highlight the modified surgical technique for the surgical treatment of jugulotympanic paragangliomas. This is a retrospective review of 34 cases of jugulotympanic paragangliomas treated in a tertiary center with respect to clinical presentation, diagnosis, and surgical treatment. Tinnitus and hearing loss were predominant symptoms. A modified technique of postauricular transcanal posterior tympanectomy with extended hypotympanic access was performed in 29 patients. Only two cases were operated with a classical transcanal approach. A canal wall down the mastoidectomy was required in three patients. The patients operated on with the modified technique had complete excision evident by absence of any lesion in computed tomography and the disappearance of tinnitus. However, two patients had recurrence of symptoms and presence of tumor in the follow-up period. These two patients underwent revision surgery. None of the patients required postoperative radiotherapy or gamma knife therapy. Jugulotympanic paragangliomas can be effectively managed with the modified technique to ensure complete removal of the lesions. This technique has not been reported earlier in the literature.
PubMed: 37564478
DOI: 10.1055/s-0042-1742766 -
Operative Neurosurgery (Hagerstown, Md.) Oct 2023The retrosigmoid approach in semisitting position (RS-SSP) is a powerful technique for removal of large vestibular schwannomas. 1 It improves extent of tumor resection...
INDICATIONS CORRIDOR AND LIMITS OF EXPOSURE
The retrosigmoid approach in semisitting position (RS-SSP) is a powerful technique for removal of large vestibular schwannomas. 1 It improves extent of tumor resection and nerve preservation. This video shows the case of a 34-year-old man with a large vestibular schwannoma, treated with the RS-SSP technique. The patient consented to the procedure and to publication of his image.
ANATOMIC ESSENTIALS NEED FOR PREOPERATIVE PLANNING AND ASSESSMENT
Preoperative MRI and bone window computed tomography are essential for optimal planning. Intraoperative monitoring throughout the surgery includes somatosensory evoked potential (SSEP) and motor evoked potential (MEP) of limbs, facial MEP and electromyography, and brainstem auditory evoked potention.
ESSENTIALS STEPS OF THE PROCEDURE
Major steps are (1) positioning of patient in SSP under SSEP recordings, 2,3 (2) ipsilateral retrosigmoid craniotomy, (3) straight dura incision parallel to sigmoid sinus, (4) opening the basal cisterns and gently elevation of cerebellum, (5) identification of Tübingen line on posterior surface of petrous bone, (6) opening and emptying the internal auditory canal (IAC) under nerves preservation, (7) intracisternal tumor debulking, (8) bimanual nerve dissection of cochlear nerve inferiorly and facial nerve medially/ventrally, (9) endoscopic investigation of IAC fundus, 4 (10) plugging the IAC with bone wax and muscle, (11) jugular vein compression before dura closure, and (12) Closure of craniotomy and wound.
PITFALLS/AVOIDANCE OF COMPLICATIONS
Correct positioning in SSP is crucial to minimize the risk of air embolism. 3.
VARIANTS AND INDICATIONS FOR THEIR USE
Additional resection of suprameatal tubercle allows extension toward the middle fossa and removal of dumbbell-shaped trigeminal schwannomas and petroclival meningiomas. 4.
Topics: Male; Humans; Adult; Neuroma, Acoustic; Neurilemmoma; Neurosurgical Procedures; Craniotomy; Ear, Inner
PubMed: 37345960
DOI: 10.1227/ons.0000000000000745 -
Medicine Dec 2023Neurofibromatosis type 2 (NF2)-related vestibular schwannoma (NF2-VS) is a rare genetic disorder that results in bilateral acoustic neuromas. However, the exact...
Neurofibromatosis type 2 (NF2)-related vestibular schwannoma (NF2-VS) is a rare genetic disorder that results in bilateral acoustic neuromas. However, the exact pathogenesis of the disease is still unclear. This study aims to use bioinformatics analyses to identify potential hub genes and therapeutic. We retrieved the mRNA expression profiles (GSE108524 and GSE141801) of NF2-VS from the database, and selected the leading 25% genes with the most variance across samples for weighted correlation network analysis. Subsequently, we conducted gene ontology term and Kyoto Encyclopedia of Genes and Genomes signaling network enrichment analyses. The STRING database was employed for protein-protein interaction (PPI) axis construction. The mRNA-miRNA modulatory network was generated via the miRTarBase database. Differentially expressed genes (DEGs) were identified via the R package "limma" in both datasets, and hub genes were screened via intersection of common DEGs, candidate hub genes from the PPI axis, and candidate hub genes from the key module. Finally, common DEGs were uploaded onto the connectivity map database to determine drug candidates. Based on our observations, the blue module exhibited the most significant relation to NF2-VS, and it included the NF2 gene. Using enrichment analysis, we demonstrated that the blue modules were intricately linked to modulations of cell proliferation, migration, adhesion, junction, and actin skeleton. Overall, 356 common DEGs were screened in both datasets, and 33 genes carrying a degree > 15 were chosen as candidate hub genes in the PPI axis. Subsequently, 4 genes, namely, GLUL, CAV1, MYH11, and CCND1 were recognized as real hub genes. In addition, 10 drugs with enrichment scores < -0.7 were identified as drug candidates. Our conclusions offered a novel insight into the potential underlying mechanisms behind NF2-VS. These findings may facilitate the identification of novel therapeutic targets in the future.
Topics: Humans; Neuroma, Acoustic; Neurofibromatosis 2; MicroRNAs; Computational Biology; RNA, Messenger
PubMed: 38115252
DOI: 10.1097/MD.0000000000036696 -
Quality of Life Research : An... Oct 2023During counseling and management of patients with vestibular schwannoma (VS), the emphasis is shifting from tumour control and nerve preservation towards maintaining or...
Patient-preferred outcomes in patients with vestibular schwannoma: a qualitative content analysis of symptoms, side effects and their impact on health-related quality of life.
PURPOSE
During counseling and management of patients with vestibular schwannoma (VS), the emphasis is shifting from tumour control and nerve preservation towards maintaining or improving health-related quality of life (HRQoL). Understanding the patients' perspective and impact of VS is, therefore, of utmost importance. The current study aimed to identify treatment outcomes preferred by patients and to explore the patient-reported VS symptoms and management-related side effects and their impact on HRQoL.
METHODS
Patients with VS were contacted through the Dutch VS association Stichting Hoormij and questioned using a semi-structured, cross-sectional online survey. Patients were asked to report and rank symptoms and side effects, with their impact on HRQoL and frequency of occurrence. Results were structured through qualitative content analysis. Coded symptoms, side effects, impacts, frequencies, and patient-preferred outcomes were analysed and summarized with descriptive statistics.
RESULTS
Of the 231 respondents, 71% were actively treated. Hearing (symptoms vs. side effects: 78.8% vs. 63.6%), balance (62.3%; 48.8%), and energy issues (33.8%; 32.6%) were the most frequently mentioned symptoms and management-related side effects. Fatigue, deafness, headaches, and hearing loss had the highest impact on HRQoL. The majority of patients identified hearing preservation (61%), balance preservation (38.5%), and reduced tinnitus (34.6%) to be the patient-preferred outcomes.
CONCLUSION
This qualitative study demonstrates that in this population many patients with VS encounter participation difficulties in their daily physical and social activities and value hearing and balance preservation, reduced tinnitus, and restored energy as preferred outcomes as they are hampered by symptoms and side effects related to hearing, balance, and energy. Healthcare professionals should consider these key points and use these and the patient-preferred outcomes in consultation, shared decision making, treatment, and follow-up to optimize patient-centred care.
Topics: Humans; Neuroma, Acoustic; Tinnitus; Quality of Life; Cross-Sectional Studies; Hearing; Treatment Outcome; Drug-Related Side Effects and Adverse Reactions; Retrospective Studies
PubMed: 37258945
DOI: 10.1007/s11136-023-03433-x