Preoperative Magnetic Resonance Imaging Research Articles

Volumetric histogram analysis of amide proton transfer-weighted imaging for predicting complete tumor response to neoadjuvant chemoradiotherapy in locally advanced rectal adenocarcinoma.

To investigate the potential of histogram analysis applied to pre-treatment amide proton transfer-weighted (APTw) imaging in predicting complete pathological regression (pCR) in patients with locally advanced rectal cancer (LARC) undergoing neoadjuvant chemoradiotherapy (nCRT). This retrospective study enrolled LARC patients who underwent preoperative rectal magnetic resonance imaging (MRI). Based on histologic assessment, the patients were divided into a pathological complete response (pCR) group or a non-pCR group. APTw histogram features, apparent diffusion coefficient (ADC), and clinical parameters were analyzed. Mann-Whitney U-test, Spearman rank correlation, and univariate and multivariate logistic regression were used for statistical analysis. The predictive performances of different models were evaluated by the receiver operating characteristic curve (ROC). One-hundred forty-five patients were included (mean age, 61.6 years ± 11.8 [SD]; 87 men). pCR patients exhibited lower pre-treatment ADC value, higher pre-treatment APTw-10%, APTw-90%, minimum, maximum, median, mean, range, and root mean square (RMS) of the primary tumor compared to non-pCR patients (all p < 0.05). APTw-10%, APTw-90%, maximum, mean, median, minimum, range, and RMS showed negative correlations with the tumor regression grade (TRG) category (r ranged between -0.457 and -0.173; all p < 0.005). Skewness, kurtosis, and entropy exhibited positive correlations with the TRG category (r = 0.278, 0.319, and 0.324, respectively; all p < 0.05). The combined model had a higher AUC of 0.930, with 93.9% sensitivity and 83.9% specificity. Histogram analysis of pre-treatment APTw may hold promise as a novel approach for predicting the response of LARC patients to nCRT. Question Predicting response to nCRT is crucial for early stratified management of LARC patients; however, current radiological studies remain inconclusive. Finding LARC patients with pCR is correlated with higher pre-treatment APTw intensity-related and lower shape-related histogram features. Clinical relevance The APTw-histogram model and the APTw-clinical combined model demonstrated strong diagnostic efficacy and clinical practicality in predicting LARC patients' responsiveness to nCRT, offering new insights for early clinical decision-making.

Multimodal MRI Deep Learning for Predicting Central Lymph Node Metastasis in Papillary Thyroid Cancer

Background: Central lymph node metastasis (CLNM) in papillary thyroid cancer (PTC) significantly influences surgical decision-making strategies. Objectives: This study aims to develop a predictive model for CLNM in PTC patients using magnetic resonance imaging (MRI) and clinicopathological data. Methods: By incorporating deep learning (DL) algorithms, the model seeks to address the challenges in diagnosing CLNM and reduce overtreatment. The results were compared with traditional machine learning (ML) models. In this retrospective study, preoperative MRI data from 105 PTC patients were divided into training and testing sets. A radiologist manually outlined the region of interest (ROI) on MRI images. Three classic ML algorithms (support vector machine [SVM], logistic regression [LR], and random forest [RF]) were employed across different data modalities. Additionally, an AMMCNet utilizing convolutional neural networks (CNNs) was proposed to develop DL models for CLNM. Predictive performance was evaluated using receiver operator characteristic (ROC) curve analysis, and clinical utility was assessed through decision curve analysis (DCA). Results: Lesion diameter was identified as an independent risk factor for CLNM. Among ML models, the RF-(T1WI + T2WI, T1WI + T2WI + Clinical) models achieved the highest area under the curve (AUC) at 0.863. The DL fusion model surpassed all ML fusion models with an AUC of 0.891. Conclusions: A fusion model based on the AMMCNet architecture using MRI images and clinicopathological data was developed, effectively predicting CLNM in PTC patients.

Normalized Total Psoas Area Predicts Early Postoperative Mobility and Perioperative Adverse Events after Adult Spinal Deformity Surgery

Background ContextPoor muscle health has been shown to predict poor perioperative outcomes following adult spinal deformity (ASD) surgery. Currently, there is limited data concerning the correlation between muscle health and recovery among patients undergoing ASD surgery. PurposeTo determine the relationship between normalized total psoas area (NTPA), postoperative mobility and adverse events (AEs) among patients undergoing ASD surgery. Study DesignRetrospective cohort study Patient SampleA retrospective analysis was performed at a single institution between January 2014 and December 2023 of patients undergoing ASD surgery by 10 board certified fellowship-trained orthopaedic spine surgeons. Outcome MeasuresPrimary outcome measures were postoperative ambulation distance on postoperative day (POD) 1, 2, 3, and 4 as well as perioperative adverse events including post-operative anemia requiring transfusion, ileus, urinary retention wound complication including dehiscence and infection, delirium, atelectasis, urinary tract infection (UTI), deep vein thrombosis (DVT), and epidural hematoma. Secondary outcome measures were 30-day reoperation rates, 30-day readmission rates, and postoperative length of stay (LOS). MethodsPatients that underwent ASD surgery at a single center (2014-2023) were included in the study. NTPA was analyzed at the L3 and L4 mid-vertebral body on preoperative magnetic resonance imaging (MRI). Receiver operating characteristic (ROC) curve analysis was used to determine gender-specific NTPA cut-off values for predicting perioperative AEs. Patients were categorized as having a low NTPA if both L3 and L4 NTPA were below the cut-off values. Multivariate logistic regression was conducted to identify confounding predictors of perioperative AEs. Results279 patients (102 males, 177 females, mean age 61.2 ± 15.2 years) were included. ROC curve analysis demonstrated L3 NTPA <805 mm2/m2 for males and <505 mm2/m2 for females and L4 NTPA <912 mm2/m2 for males and <714 mm2/m2 for females as cut-off values predicting perioperative AEs. 103 patients (36.9%, 42 males, 61 females) were below these cut-off values and were in the low NTPA cohort. The remaining 176 patients (63.1%, 60 males, 116 females) were in the normal NTPA cohort. The low NTPA group had a higher overall perioperative AEs (70.9% vs 39.2%, p<0.001), and lower ambulation distances on postoperative day 1 and 2 compared to the normal NTPA group (p=0.021, p=0.028, respectively). On multivariate analysis, there were no other predictors of perioperative AEs. ConclusionsLow L3 and L4 NTPA is associated with lower early postoperative mobility and higher rates of perioperative AEs among patients undergoing ASD surgery. These findings stress the importance of muscle health in recovery after ASD surgery.

The safety, accuracy, and feasibility of robotic assistance in neuro-oncological surgery.

Over the past 3 decades, robotic technology has advanced significantly across surgical fields, driven by improvements in versatility, stability, skill, and tactile properties. Neurosurgery has led the way in integrating robotics to improve the accuracy and safety of procedures that require high precision. This study aimed to present one of the largest series in the literature and investigate the feasibility and effectiveness of robotic assistance in neuro-oncological surgery. The authors performed a retrospective review of the medical records of patients who underwent stereotactic biopsy only and biopsy and laser interstitial thermal therapy (LITT) using the Robotic Surgical Assistant (ROSA) system. The ROSA system was used for trajectory planning as well as the precise alignment and insertion of the needle and/or laser catheter. All procedures were performed by a single neurosurgeon. Electronic medical records were reviewed for patient demographics, preoperative clinical deficits, diagnosis, preoperative and postoperative MR images, lesion characteristics including location and volume, postoperative complications, and deficits. A total of 348 patients were identified. The mean age at surgery was 61.4 years, with 171 (49.1%) females. The most common presentations were GBM (40.5%, n = 141), metastasis (16.4%, n = 57), and radiation necrosis (9.8%, n = 34). A total of 189 (54%) patients underwent stereotactic biopsy only, and 159 (46%) underwent biopsy and LITT. The diagnostic yield of the cases was 98.6%, with only 5 cases having inconclusive pathology. Two (0.6%) patients experienced postoperative complications that resolved during follow-up. Ten (2.9%) patients developed asymptomatic subcentimeter hematomas following the procedure that did not require further intervention. No long-term consequences or permanent deficits occurred in any case within a median follow-up duration of 4.4 months (IQR 1-11.2 months). These results indicate that a robot-assisted approach for stereotactic biopsies and LITT is associated with a comparable diagnostic yield and safety profile for frameless and frame-based techniques. Its precision, user-friendly interface, and adaptability contribute to its suitability for such procedures. Future research, especially in long-term results and cost-effectiveness, will be crucial in fully understanding the utility and potential of this technology for broader applications in the field.

Surgical experience overcomes the impact of prostatic-urethral anatomy on continence recovery after robotic prostatectomy: comprehensive analysis on 366 cases.

To investigate the relationship between a set of prostate-urethral complex (PUC) measurements and incontinence after robot-assisted radical prostatectomy (RARP). The study included data from patients undergoing RARP performed by 2 expert surgeons between 2019 and 2022, with data about preoperative magnetic resonance imaging (MRI) and functional follow-up. Continence status was assessed according to a stringent definition (no PADS used). MRIs were evaluated to calculate prostatic urethral length, membranous urethral length, membranous urethral width, levator ani thickness, and prostate shape. The association of PUC measurements with continence after RARP was studied. Secondarily, we evaluated whether pre-determined cut-off values of PUC measurements could be associated with time to continence. Cumulative hazard incidence analysis was performed by the Nelson-Aalen hazard function. Cumulative incidence hazard curves were built; the Peto-Peto test was used to evaluate the difference among the curves. 366 patients were included. At the 12-month follow-up, 333 patients (90.1%) were continent. Classification of PUC measurements overlapped between continent and noncontinent patients. However, a statistically significant difference was observed for levator ani thickness, greater in continent patients (12.8mm vs. 11.7; p = 0.02). Multivariable models found BMI as independent predictor of incontinence (HR 1.04, 95% C.I 1.00-1.07, p = 0.04). None of PUC measurements associated with incontinence. Also, cumulative hazard incidence analysis at 3 / 6 / 12-months found no statistically significant difference in PUC measurements. No association was found between anatomical characteristics of PUC and continence or time to continence after RARP performed by proficient surgeons. Our data would suggest that once the surgeon has surpassed the learning curve, anatomical variations do not significantly affect the appropriate and proficient execution of the prostate apex dissection during RARP.

Transient and permanent hydrocephalus following resection of brain metastases located in the posterior fossa: incidence, risk factors and the necessity of perioperative external ventricular drainage placement.

Prophylactic insertion of an external ventricular drainage (EVD) prior to the resection of posterior fossa metastases (PFMs) is a common approach to address postoperative transient and permanent hydrocephalus. However, predicting surgery-related hydrocephalus in the preoperative phase continues to be a challenge. This study aims to analyze the incidence, preoperatively collectable risk factors and necessity of perioperative external ventricular drainage placement after posterior fossa metastasis surgery. All patients undergoing surgery for PFMs at the authors' neuro-oncological center between 2015 and 2021 were identified and assessed for postoperative hydrocephalus occurrence. Tumour volume, edema volume, and 4th ventricle volume were assessed on preoperative magnetic resonance imaging scans using the IntelliSpace Portal 5.0. A multivariable logistic regression analysis was performed to identify possible predictors for postoperative hydrocephalus occurrence. Postoperative hydrocephalus occurred in 14 of the 130 identified PFM patients (11%). Multivariable analysis and receiver operating characteristic (ROC) analysis revealed a 4th -ventricle-to-tumor-volume ratio ≤ 0.02 (OR 33.1, 95% CI 3.8-284.3, p = 0.001), an edema-to- tumor-volume ratio ≤ 0.85 (OR 10.6, 95% CI 2.4-47.4, p = 0.002), an imaging-morphological contact to the 4th ventricle (OR 5, 95% CI 1.4-18, p = 0.013), and multiple intracranial metastases (OR 2.4, 95% CI 1-5.9, p = 0.045) as independent predictors for surgery-related postoperative hydrocephalus occurrence. The present study identifies preoperatively detectable risk factors for the occurrence of postoperative hydrocephalus following surgery for PFMs. These findings may provide guidance in clinical decision-making regarding prophylactic EVD placement.

Enhancing Precision in Rectal Cancer Care: Unravelling the Correlation Between MRI Locoregional Staging and Prognostic Factors, With Post-resection Pathology.

Introduction Magnetic resonance imaging (MRI) serves as a pivotal tool in the preoperative assessment of rectal cancer. This study aims to evaluate the accuracy of preoperative MRI pelvis in rectal cancer for locoregional staging, circumferential margin (CRM+), and vascular invasion (V1) with postoperative histopathological findings. Methods All patients who underwent preoperative staging MRI pelvis scanning for histology-proven primary rectal adenocarcinoma between January 2020 and July 2022 were included in this study. Preoperative MRI assessment data, including tumor (T), nodal (N) staging, and other prognostic factors, including circumferential margin and vascular invasion, were compared with histopathological reports. Sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), and accuracy were calculated. Agreement between MRI and pathology reports was evaluated using the weighted kappa statistic. Results The study included 143 patients. The accuracy of MRI is at its peak for T0 and T4 tumors (T0-97.9%,T4-93.37). The weighted kappa statistic for T staging is 0.401, and for N staging, it is 0.286. The standard kappa statistic for extramural vascular invasion (V) and circumferential resection margin (CRM) is 0.269 and 0.225, respectively. Conclusion MRI demonstrates fair agreement with pathology regarding T and N staging and exhibits high specificity for CRM and V1.

Association of imaging biomarkers with molecular subtypes of medulloblastoma.

Background and purpose: The World Health Organization (WHO) subdivided medulloblastoma into genetic and histopathological groups, each with a specific therapeutic intervention and different clinical outcomes. These subtypes may present with distinct imaging features. Therefore, the current study aimed to identify magnetic resonance imaging (MRI) biomarkers to predict the precise pathological characteristics of medulloblastoma. Methods: This study included 28 patients with a first diagnosis of medulloblastoma who underwent preoperative brain MRI with subsequent surgical resection and histopathological confirmation at our hospital between 2010 and 2022. Conventional MRI parameters, including apparent diffusion coefficient (ADC) mean values, were correlated with molecular subtypes to identify distinct MRI biomarkers. Results: Out of 28 tumors, two (7.1%) tumors exhibited wingless (WNT) activation, thirteen (46.4%) exhibited sonic hedgehog (SHH) activation, and thirteen (46.4%) exhibited non-WNT/non-SHH activation (Group 3 or 4). Statistical analysis revealed a significant association of SHH-activated tumors with paramidline/cerebellar location and the presence of peritumoral edema (p value = <0.0001). No significant correlations were found between the genetic subtypes and the other MRI parameters. A distinctive distribution of the ADC-mean values among the various genetic subtypes with recognizable tendencies was identified. However, it was statistically insignificant. Conclusion: Conventional MRI features of the paramidline/hemispheric location and the presence of peritumoral edema were significantly correlated with the SHH activated pathway and hence can be used to facilitate the preoperative implementation of SHH-targeted therapeutic intervention. Although the ADC-mean measurements were not statistically significant, a recognizable distribution of values among the various genetic subtypes was identified.

Diffusion-weighted imaging findings predictive of postoperative recurrence of chronic subdural hematoma

ObjectivesTo identify the brain magnetic resonance imaging (MRI) findings associated with the postoperative recurrence of chronic subdural hematoma (CSDH). MethodsWe examined 1099 consecutive patients admitted to our hospital with CSDH between 2005 and 2014. Of those, 1021 who underwent surgery for CSDH and were followed-up for >3 months after surgery were included. Preoperative brain MRI findings were classified as homogeneous, laminar, separate, or trabecular, according to the nature of the hematoma. Postoperative recurrence was defined in patients who required reoperation for ipsilateral hematoma growth within three months of surgery. The clinical and radiological factors associated with postoperative recurrence were evaluated using univariate and multivariate analyses. ResultsOf the 1021 CSDH patients with CSDH who underwent surgery, 91 (8.9%) experienced postoperative recurrence. Postoperative recurrence was significantly associated with male sex (p = 0.0004) and hematoma volume (p < 0.0001). Additionally, isotype or separate types of hematoma on computed tomography (CT) (p < 0.0001) and laminar/separate types of hematoma types on MRI (p = 0.0008) were significant. Multivariate analysis revealed odds ratios of 2.50 (95% CI, 1.45–4.61; p = 0.0007) for male sex and 3.05 (95% CI, 1.95–4.87; p < 0.0001) for iso/separate hematoma types in CT. Conversely, among the patients who underwent MRI, multivariate analysis revealed odds ratios of 4.33 (95% CI, 1.20–27.92; p = 0.001) for male sex and 4.88 (95% CI, 1.90–14.18; p = 0.023) for laminar/separate hematoma types. ConclusionWhile distinguishing the nature of hematomas is challenging with brain CT examination, detailed laminar/trabecular differentiation using MRI images may predict postoperative recurrence.

Diffusion-weighted imaging based on intravoxel incoherent motion: correlation with molecular prognostic factors and subtypes in breast cancer.

Intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI), which indicates biological tissue attributes, may be applied to accurately assess breast tumors. To analyze the IVIM parameters of different molecular prognostic factors and subtypes to find out whether there are any connections. A total of 181 patients enrolled in this retrospective study had preoperative magnetic resonance imaging (MRI) examinations, and pathologies were verified as breast cancers. Regions of interest were placed at all slices of the parameter maps (D, tissue diffusivity; ADC, apparent diffusion coefficient; f, perfusion fraction; and D*, pseudo-diffusivity maps) of IVIM and generated parameter values to be used for comparative analysis among molecular prognostic factors and subtypes. D and ADC were greater in estrogen receptor (ER)-negative, human epidermal growth factor receptor 2 (HER2)-positive, and Ki67-low expression groups (all P values < 0.05). The progesterone receptor (PR)-negative group had a higher D value (P < 0.05). f was larger in the lymph node metastasis-negative group and the PR-positive group (P = 0.012 and 0.046, respectively). Among breast cancer subtypes, D and ADC were different between the HER2-overexpression and the Luminal B (HER2-negative) subtypes (P = 0.019 and 0.028, respectively). The difference in D between the luminal and non-luminal subtypes was statistically significant (P = 0.008). The triple-negative subtype significantly differs from the other subtypes in D* and f (P = 0.012 and 0.016, respectively). IVIM-related metrics exhibited relationships with breast cancer molecular prognosis factors and subtypes.

Endoscopic Occipital Transtentorial Approach for Dorsal Midbrain Cavernous Malformation: Technical Notes With Illustrative Case

BackgroundThe dorsal midbrain, an anatomically intricate region, presents significant challenges for traditional surgical interventions due to the heightened risk of vascular and neurological injury, and the necessity of brain tissue retraction. MethodsThis study retrospectively reviewed the case of a 29-year-old male diagnosed with a cavernous malformation located in the dorsal aspect of the left midbrain. The patient underwent resection via the endoscopic occipital transtentorial approach (EOTA) in July 2024. Comprehensive records were analyzed, including preoperative magnetic resonance imaging (MRI) and computed tomography (CT) imaging, detailed surgical notes, and postoperative outcomes. ResultsThe patient initially presented with headaches and diplopia. Imaging revealed a 17x13 mm tumor in the dorsal aspect of the left midbrain, associated with obstructive hydrocephalus. The 2.5-hour EOTA surgery resulted in complete resection of the tumor, with the resolution of headache symptoms and improvement of diplopia. No new complications were reported postoperatively. The patient was discharged seven days post-surgery without the need for intensive care unit admission. Pathological examination confirmed the diagnosis of a cavernous malformation. Additionally, the EOTA facilitated a concurrent endoscopic third ventriculostomy, and no evidence of hydrocephalus was observed during the three-month follow-up period. ConclusionThe EOTA constitutes a significant advancement in neurosurgical techniques for the resection of dorsal midbrain tumors, enhancing surgical precision and safety. This approach contributes to improved patient outcomes and a reduction in complication rates. Further studies are warranted to validate these findings and to establish standardized protocols for the application of EOTA in midbrain tumor resection.

Predicting intraoperative 5-ALA-induced tumor fluorescence via MRI and deep learning in gliomas with radiographic lower-grade characteristics.

Lower-grade gliomas typically exhibit 5-aminolevulinic acid (5-ALA)-induced fluorescence in only 20-30% of cases, a rate that can be increased by doubling the administered dose of 5-ALA. Fluorescence can depict anaplastic foci, which can be precisely sampled to avoid undergrading. We aimed to analyze whether a deep learning model could predict intraoperative fluorescence based on preoperative magnetic resonance imaging (MRI). We evaluated a cohort of 163 glioma patients categorized intraoperatively as fluorescent (n = 83) or non-fluorescent (n = 80). The preoperative MR images of gliomas lacking high-grade characteristics (e.g., necrosis or irregular ring contrast-enhancement) consisted of T1, T1-post gadolinium, and FLAIR sequences. The preprocessed MRIs were fed into an encoder-decoder convolutional neural network (U-Net), pre-trained for tumor segmentation using those three MRI sequences. We used the outputs of the bottleneck layer of the U-Net in the Variational Autoencoder (VAE) as features for classification. We identified and utilized the most effective features in a Random Forest classifier using the principal component analysis (PCA) and the partial least square discriminant analysis (PLS-DA) algorithms. We evaluated the performance of the classifier using a tenfold cross-validation procedure. Our proposed approach's performance was assessed using mean balanced accuracy, mean sensitivity, and mean specificity. The optimal results were obtained by employing top-performing features selected by PCA, resulting in a mean balanced accuracy of 80% and mean sensitivity and specificity of 84% and 76%, respectively. Our findings highlight the potential of a U-Net model, coupled with a Random Forest classifier, for pre-operative prediction of intraoperative fluorescence. We achieved high accuracy using the features extracted by the U-Net model pre-trained for brain tumor segmentation. While the model can still be improved, it has the potential for evaluating when to administer 5-ALA to gliomas lacking typical high-grade radiographic features.

Clinical Evaluation of the NaviNetics Stereotactic System Using Intraoperative Portable Surgical Imaging System in DBS Surgery

BACKGROUND AND OBJECTIVES: A typical workflow for deep brain stimulation (DBS) surgery consists of head frame placement, followed by stereotactic computed tomography (CT) or MRI before surgical implantation of the hardware. At some institutions, this workflow is prolonged when the imaging scanner is located far away from the operating room, thereby increasing workflow times by the addition of transport times. Recently, the intraoperative O-arm has been shown to provide accurate image fusion with preoperative CT or MR imaging, suggesting the possibility of obtaining an intraoperative localization scan and postoperative confirmation. In this article, we aim to evaluate the compatibility of the stereotactic frame system with the intraoperative O-arm system regarding lead accuracy and surgical flow. METHODS: A total of 17 patients undergoing DBS surgery for movement disorders were evaluated. One patient underwent both the stereotactic CT and O-arm localization, while 16 patients underwent only intraoperative O-arm localization. Following lead placement, intraoperative O-arm imaging was obtained to evaluate the accuracy of the lead placement. Accuracy was defined as the error measured as the distance from the center of the planned trajectory to the cannula. RESULTS: Less than 0.1 mm difference was found between the O-arm imaging technique and CT image localization of the NaviNetics stereotactic head frame in DBS surgery. Of the 16 patients who underwent the intraoperative O-arm imaging alone, the targets included bilateral ventral intermediate nucleus (16 leads), bilateral globus pallidus internus (4 leads), and subthalamic nucleus (12 leads). The mean ± SD radial error in the probe's eye view was 0.71 ± 0.33 mm for n = 32 leads. No tract hemorrhage was observed. CONCLUSION: Intraoperative O-arm imaging can be used safely and effectively for stereotactic registration and lead placement confirmation with the stereotactic system in both awake and asleep DBS surgery.

Trainee experience in virtual reality simulation in orbital surgery

ABSTRACT Purpose To demonstrate the role of Virtual Reality (VR) in orbital surgery as an educational tool for surgical trainees. Methods A single-center prospective study was conducted from February 2021 to April 2023. Pre-operative magnetic resonance imaging and computed tomography scans were used to create patient-specific VR models of the orbit using ImmersiveTouch Software. Accuracy of the models was qualitatively assessed by an attending oculofacial surgeon. Surveys regarding understanding of the surgical plan were distributed to trainees before the VR simulation, after its use, and following surgery. Results VR models were made for 28 cases, and 52 surveys were completed by residents in ophthalmology, otolaryngology, plastic surgery, and by oculofacial fellows. The VR models for 93% of the cases were rated as accurate by the attending physician. Assigned trainee tasks included measurement of an orbital fracture (n = 1, 1.9%), measurement of orbital tumors (n = 12, 23.1%), and drilling of the orbital bone to simulate an orbital decompression (n = 10, 19.2%). The tumor measurements made by trainees using the VR system were not significantly different than those recorded by the radiologists (p > 0.05). Early trainees (i.e. residents and the first year oculofacial fellow) noted significant improvement in their understanding of the pathology relative to important anatomical landmarks within the orbit after utilizing the VR models prior to surgery (p < 0.001). Conclusions Patient-specific VR models accurately simulate orbital pathology and may improve trainees’ understanding of orbital anatomy early in their careers.

The impact of supraspinatus tear on subscapularis muscle atrophy and fatty infiltration.

Aimed to report the prevalence and predisposing factors affecting subscapularis muscle atrophy and fatty infiltration (MAFI) in patients without a subscapularis tear, and to analyze the effect of this condition on surgical outcomes. Between 2020 and 2022, 153 patients (mean age 58.1 ± 10.2 years; 84 men and 69 women) who underwent repair of posterosuperior cuff tears, with no subscapularis tears identified during arthroscopy were retrospectively analyzed. Baseline characteristics, preoperative and follow-up (6 months) magnetic resonance imaging findings, arthroscopic findings, and clinical outcomes (>1 year) were recorded. The prevalence of subscapularis MAFI (Goutallier grade 1 or 2) was 73.9% (113/153), of which the prevalence of Goutallier grade 2 was 23.5% (36/153). From multivariable logistic regression analysis, female sex (odds ratio [OR], 5.6; 95% CI, 1.7-18.6; P=0.005), older age (OR, 1.1; 95% CI, 1.0-1.1; P=0.052), advanced supraspinatus MAFI by Goutallier grade (OR, 3.2; 95% CI, 1.5-6.9; P=0.004), and synovitis (OR, 2.8; 95% CI, 1.1-7.9; P=0.030) were identified as independent predisposing factors for subscapularis MAFI. However, patients with preoperative subscapularis MAFI exhibited similar final range of motion, pain and function, and belly press strength compared to those without preoperative subscapularis MAFI. Subscapularis MAFI is frequently observed conditions even in the absence of subscapularis tears, and this condition could be affected by supraspinatus MAFI, female sex, older age, and synovitis. However, because subscapularis MAFI does not affect the surgical outcome, surgeons need not be concerned about this condition when repairing posterosuperior rotator cuff tear. Level of evidence: IV.

Increased global posterior tibial slope is significantly associated with higher ACL graft signal intensity on 2-Year postoperative MRI after primary ACL reconstruction using hamstring tendon autografts

BackgroundThe healing and remodeling process of tendon grafts after anterior cruciate ligament (ACL) reconstruction (ACLR) has received significant attention. This study aims to identify preoperative factors associated with postoperative signal intensity of the ACL graft after primary ACLR.MethodsA total of 90 patients underwent primary ACLR using hamstring tendon autografts by the same senior surgeon between January 2013 and December 2020 were included. Patients were followed up and scheduled for a 2-year postoperative magnetic resonance imaging (MRI) scan at our institute. Concomitant injuries were confirmed by arthroscopy. Posterior tibial slope (PTS) and anterior tibial subluxation (ATS) were measured on preoperative MRI, whereas the normalized signal intensity of the ACL graft was evaluated on postoperative MRI and calculated as the ratio of the graft signal intensity to that of the patellar tendon. Multivariable linear regression models were performed to identify preoperative factors associated with the postoperative signal intensity of the ACL graft.ResultsMultivariable analyses showed that increased global PTS (GPTS) (P = 0.008) and concomitant articular cartilage injuries (P = 0.005) were associated with higher average signal intensity of the ACL graft on two-year postoperative MRI, while preoperative internal rotational tibial subluxation (IRTS) calculated as the difference between lateral ATS and medial ATS did not show a significant association. Specifically, an increased GPTS was significantly associated with higher signal intensity in the proximal section of the ACL graft (P = 0.005), whereas no significant associations were observed in the middle and distal sections.ConclusionsIncreased preoperative GPTS was significantly associated with higher signal intensity of the ACL graft on 2-year postoperative MRI after primary ACLR, suggesting that a steep preoperative tibial slope may contribute to a suboptimal ligamentization process in hamstring tendon autografts.Level of evidenceLevel III, retrospective cohort study.

Automatic segmentation-based multi-modal radiomics analysis of US and MRI for predicting disease-free survival of breast cancer: a multicenter study

BackgroundSeveral studies have confirmed the potential value of applying radiomics to predict prognosis of breast cancer. However, the tumor segmentation in these studies depended on delineation or annotation of breast cancer by radiologist, which is often laborious, tedious, and vulnerable to inter- and intra-observer variability. Automatic segmentation is expected to overcome this difficulty. Herein, we aim to investigate the value of automatic segmentation-based multi-modal radiomics signature and magnetic resonance imaging (MRI) features in predicting disease-free survival (DFS) of patients diagnosed with invasive breast cancer.MethodsThis retrospective multicenter study included a total of 643 female patients with invasive breast cancer who underwent preoperative ultrasound (US) and MRI for prognostic analysis. Data (n = 480) from center 1 were divided into training and internal testing sets, while data (n = 163) from centers 2 and 3 were analyzed as the external testing set. We developed automatic segmentation frameworks for tumor segmentation by deep learning. Then, Least absolute shrinkage and selection operator Cox regression was used to select features to construct radiomics signature, and corresponding radiomics score (Rad-score) was calculated. Finally, six models for predicting DFS were constructed by using Cox regression and assessed in terms of discrimination, calibration, and clinical usefulness.ResultsThe multi-modal radiomics signature combining intra- and peri-tumoral radiomics signatures of US and MRI achieved a higher C-index in the internal (0.734) and external (0.708) testing sets than most other radiomics signatures in predicting DFS, and successfully stratified patients into low- and high-risk groups. The multi-modal clinical imaging model combining the multi-modal Rad-score and clinical traditional MRI model-score resulted in a higher C-index (0.795) than other models in the external testing set, and it had a better calibration and higher clinical benefit.ConclusionsThis study demonstrates that the multi-modal radiomics signature derived from automatic segmentations of US and MRI is a promising risk stratification biomarker for breast cancer, and highlights that the appropriate combination of multi-modal radiomics signature, clinical characteristics, and MRI feature can improve performance of individualized DFS prediction, which might assist in guiding decision-making related to breast cancer.

NIMG-49. IMAGING PREDICTIVE FACTORS OF BRAIN ADHESION IN SUPRATENTORIAL MENINGIOMA

Abstract OBJECTIVES 80 % of meningioma are benign and are classified as WHO grade 1. However, meningioma frequently adheres to surrounding brain and make tumor detach difficult during surgery. This study retrospectively analyzed the adhesion of meningioma to the brain based on preoperative MR images and operative findings. METHODS We retrospectively reviewed 238 tumor planes of 60 supratentorial meningioma cases with WHO grade 1 (parasagittal: 15, convexity: 20, falcine: 7, sphenoidal ridge 13 and frontal base 5) underwent surgical treatment. The tumor adhesion to the surrounding brain was defined during surgery as the rupture of arachnoid membrane or leaving tumor capsule due to tight adhesion. The location of MRI image was identified during surgery and verified reference to operation video postoperatively. We assessed following items, tumor diameter, T2 hyper rim, T1 hypo rim, FLAIR hypo rim and brain edema of surrounding tumor. We performed univariate analysis for each item with and without adhesion, and extracted predictors for tumor adhesion by logistic regression analysis. RESULTS We confirmed 127 tumor planes without adhesion and 111 tumor planes adhered to surrounding brain. The cutoff value obtained from the ROC curve for tumor adhesion and tumor diameter was 2.3 cm. In univariate analysis, tumor diameter ≧ 2.3 cm, T2 hyper rim, T1 hypo rim, FLAIR hypo rim and brain edema of surrounding tumor were significantly associated with adhesion. In logistic regression analysis, tumor diameter ≧ 2.3 cm (odds ratio (OR) 2.7, P = 0.02), T2 hyper rim (OR 0.04, P &amp;lt; 0.001), and brain edema of surrounding tumor (OR 25, P &amp;lt; 0.001) were significantly independent predictive factors for tumor adhesion. CONCLUSION Meningioma adhesion to surrounding brain might be predicted by tumor diameter ≧2.3 cm, T2 hyper rim, and brain edema of surrounding tumor.

SURG-31. HYBRID THERAPY FOR NEWLY DIAGNOSED AND RECURRENT GLIOBLASTOMA: STAGED PROCEDURE INTEGRATING OPEN SURGICAL RESECTION WITH LASER INTERSTITIAL THERMAL THERAPY

Abstract BACKGROUND Glioblastoma (GBM) is the most common and aggressive primary malignant brain tumor in adults with a median overall survival (OS) of 15.6 months. Despite advancements, 5-year survival rates have not significantly improved. Laser interstitial thermal therapy (LITT) has been employed to treat both newly diagnosed (nGBM) and recurrent GBM (rGBM) with demonstrable safety and efficacy. Traditionally, LITT has been limited to smaller lesions given physical and thermal constraints. OBJECTIVE We present two case examples of a novel, hybrid treatment approach to GBM, utilizing both surgery and laser ablation as part of a single-staged procedure. METHODS Two geriatric (&amp;gt;65 years) patients with nGBM or rGBM were treated with surgical resection followed by LITT the subsequent day. Both patients underwent preoperative magnetic resonance imaging (MRI) showing multifocal disease with a dominant component, causing mass effect in the second case, and an unresectable component. RESULTS The first case underwent surgical resection of a large, multicentric rGBM in the parieto-occipital region, followed by LITT of an unresectable lesion in the inferior temporal gyrus. The second patient underwent surgical resection of the dominant temporal lobe component, and LITT of the insular component. Neither patient had intraoperative or ablation complications. Both patients had stable postoperative neurological exams and were discharged on the day after ablation, with no new deficits at follow-up. CONCLUSION The prognosis for GBM remains dismal despite significant research and attempts at advancements in patient management. Surgical resection is a critical component of the GBM treatment paradigm. However, surgery alone is not sufficient in many patients. LITT has shown promise for improving GBM outcomes, mainly due to its minimal invasiveness, enhanced immune responses, BBB disruption, and cytoreductive potential. We demonstrate a novel, hybrid approach to GBM using hybrid surgical resection and LITT in a single-staged procedure to overcome traditional constraints of LITT.

Diagnostic value of the flare sign in predicting extracapsular extension in metastatic axillary lymph nodes and nodal status on breast magnetic resonance imaging.

This study aimed to evaluate the diagnostic performance of breast magnetic resonance imaging (MRI) in predicting extracapsular extension (ECE) and axillary nodal status in the axillary metastatic lymph nodes of patients with breast cancer. The preoperative MRI scans of 92 patients with breast cancer and axillary metastases who did not receive neoadjuvant treatment between January 2018 and January 2024 were retrospectively examined. The presence of an increased signal in the axillary fatty tissue surrounding the lymph node (flare sign) on T2-weighted images, irregular nodal contour (shaggy margin), axillary asymmetry (difference in the number and size of lymph nodes compared with the unaffected axilla), loss of the fatty hilum in the most suspicious lymph node, and morphological features on T1-weighted images were assessed. Each dissected axillary lymph node was examined for ECE, and the histopathological results were recorded. Axillary flare sign was significantly associated with the presence of ECE (P < 0.001), number of lymph nodes with ECE (P < 0.001), the presence of ≥4 axillary metastatic lymph nodes (P < 0.001), size of the primary tumor (P = 0.033), lymphovascular invasion in the primary tumor (P < 0.001), and presence of perineural invasion (P = 0.001). The flare sign exhibited 65.7% sensitivity, 96% specificity, 97.8% positive predictive value, 51.1% negative predictive value, and 73.9% accuracy in predicting ECE. Additionally, the receiver operating characteristic curve analysis revealed an area under the curve of 0.808 (95% confidence interval: 0.719-0.898). The flare sign has high performance in predicting ECE and axillary nodal status and is associated with primary tumor aggressiveness, indicating its potential utility in preoperative evaluation. The flare sign on breast MRI may play a crucial role in preoperative planning, surgical decision-making, and axillary status assessment by accurately predicting ECE.