Patient Surgical Planning Research Articles

Preoperative CT-Based Radiomics Combined With Nodule Type to Predict the Micropapillary Pattern in Lung Adenocarcinoma of Size 2cm or Less: A Multicenter Study.

PurposeTo construct an optimal radiomics model for preoperative prediction micropapillary pattern (MPP) in adenocarcinoma (ADC) of size ≤ 2 cm, nodule type was used for stratification to construct two radiomics models based on high-resolution computed tomography (HRCT) images.Materials and MethodsWe retrospectively analyzed patients with pathologically confirmed ADC of size ≤ 2 cm who presented to three hospitals. Patients presenting to the hospital with the greater number of patients were included in the training set (n = 2386) and those presenting to the other two hospitals were included in the external validation set (n = 119). HRCT images were used for delineation of region of interest of tumor and extraction of radiomics features; dimensionality reduction was performed for the features. Nodule type was used to stratify the data and the random forest method was used to construct two models for preoperative prediction MPP in ADC of size ≤ 2 cm. Model 1 included all nodule types and model 2 included only solid nodules. The receiver operating characteristic curve was used to assess the prediction performance of the two models and independent validation was used to assess its generalizability.ResultsBoth models predicted ADC with MPP preoperatively. The area under the curve (AUC) of prediction performance of models 1 and 2 were 0.91 and 0.78, respectively. The prediction performance of model 2 was lower than that of model 1. The AUCs in the external validation set were 0.81 and 0.72, respectively. The DeLong test showed statistically significant differences between the training and validation sets in model 1 (p = 0.0296) with weak generalizability. There was no statistically significant difference between the training and validation sets in model 2 (p = 0.2865) with some generalizability.ConclusionNodule type is an important factor that affects the performance of radiomics predictor model for MPP with ADC of size ≤ 2 cm. The radiomics prediction model constructed based on solid nodules alone, can be used to evaluate MPP and may contribute to proper surgical planning in patients with ADC of size ≤ 2 cm.

Open Evaluation of the Peroneal Tendons Should Be Considered in Patients With Chronic Lateral Ankle Instability Undergoing Ankle Arthroscopy With Lateral Ankle Stabilization

Peroneal tendon pathology is commonly associated with chronic lateral ankle instability. Foot and ankle surgeons often rely on preoperative magnetic resonance imaging (MRI) for identification of related pathology and surgical planning in these patients. The purpose of this study was to assess the ability of preoperative MRI to accurately detect peroneal tendon pathology in patients with chronic lateral ankle instability. Consecutive surgical cases involving arthroscopic evaluation and management of lateral ankle instability sequelae were evaluated retrospectively. Preoperative MRI were compared to intraoperative findings in order to determine the sensitivity, specificity, positive and negative predictive values. Eighty-two patients met inclusion criteria, 58 females and 24 males. The average age at the time of surgery was 46 years (range 13-75). Peroneal tendon pathology was identified intraoperatively in 76 (92.7%) patients and on MRI in 40 (48.8%) patients. The most commonly identified pathologies were tenosynovitis, tendinopathy and longitudinal split/tear, with the peroneus brevis tendon being most commonly involved. MRI was 38.7% specific, 50.0% sensitive, had a positive predictive value of 92.5%, and a negative predictive value of 7.1%.While MRI is a helpful study for evaluation of co-pathologies and surgical planning in patients with lateral ankle instability, procedural selection should not be solely based on MRI results, and the peroneal tendons should be evaluated intraoperatively in patients undergoing arthroscopic procedures for lateral ankle instability.

Sentinel Epileptiform Discharges Activating Two Seizure Networks on Intracranial EEG.

Sentinel epileptiform discharges (SEDs) are epileptiform transients preceding the onset of a focal seizure seen on scalp EEG. Despite their potential localizing value, formal study of SED has been limited. The authors report a patient with MRI-negative focal-onset epilepsy whose seizures on scalp and intracranial EEG were always preceded by SED. Although the location and morphology of the SED was invariable, the seizures after the discharge were of two clearly distinct types, each with different semiology and region of spread on intracranial EEG. This suggests that the SED played a role in activating two distinct seizure networks. A right temporal lobectomy with amygdalohippocampectomy was performed. The resection included both the region of the SED as well as the seizure-onset zone of the more common seizure type, achieving seizure freedom at 3 years after surgery. Further research exploring whether the localization of SED is a reliable indicator of the seizure-onset zone could aid surgical planning in patients whose seizures are preceded by SED.

Novel strategy to predict high risk of inferior alveolar nerve injury during extraction of lower third molars based on assessment of computed tomographic images of multiple anatomical features

Preoperative assessment is essential to prevent inferior alveolar nerve (IAN) injury during surgical extraction of the lower third molar (LM3). Here, we aimed to establish an assessment system to predict IAN injury during surgical extraction of the LM3. We conducted a retrospective cohort study on 115 patients diagnosed as ‘high-risk’ based on our previous risk assessment method involving three anatomical features of the inferior alveolar canal using computed tomographic (CT) images. We evaluated the occurrence of neurosensory impairment in these high-risk patients, and its association with novel anatomic features based on CT images. Neurosensory impairments were observed in 19 patients (16.5%). The inferior alveolar canal major diameter (p < 0.0001) and lingual bone thickness (p = 0.0039) were significantly associated with the occurrence of neurosensory impairment during LM3 extraction. Receiver operating characteristic curves were used to determine cut-off values of these quantitative factors to specifically predict IAN injury. Preoperative risk assessment with quantitative factors based on anatomical features observed on CT images may facilitate more appropriate surgical planning for patients at a high risk of IAN injury.

Quantitative Analysis of Eyeball Rotation During Lateral Gaze in Intermittent Exotropia: A Magnetic Resonance Imaging Study.

PurposeTo evaluate the eyeball rotation during lateral gaze in patients with intermittent exotropia (IXT) using three-dimensional magnetic resonance imaging (MRI).MethodsIn this prospective observational study, patients with IXT (n = 29) underwent orbital MRI during central, right, and left gazes. Fixation targets were placed at a 40° angle for lateral gaze. After acquisition of MR images, the position of the static tissues other than the eyeball in the MR images were matched three-dimensionally. The optical axis was defined as the perpendicular line to its lens passing through the corneal vertex. The rotation angle was measured as the angle between optical axes in central gaze and lateral gaze using ImageJ. A difference of 3° or more in the rotational angle between both eyes was considered a significant difference.ResultsEight patients (26.7%) had a larger adduction angle than the abduction angle of the fellow eye and six patients (20.0%) showed a smaller adduction angle during lateral gaze on at least one side. There was no significant factor associated with the pattern of rotation.ConclusionsAlmost one-half of the patients with IXT had significant difference in the rotation angle between both eyes during lateral gaze. Measurement of the rotation angle during lateral gaze using MRI showed that IXT is not a perfectly comitant disturbance of gaze in some subjects.Translational RelevanceQuantitative analysis for eye movements using MRI can provide useful information for physiologic mechanism and proper surgical planning in patients with IXT.

Surgical planning in patients with brain glioma using diffusion tensor MR imaging and tractography

BackgroundDiffusion-tensor imaging (DTI) is a magnetic resonance imaging (MRI) technique that depicts the integrity of white matter (WM) tracts. This study was conducted to assess the utility of DTI tractography as an imaging technique in assessment of brain gliomas and planning of the surgical corridor.ResultsTwenty adult patients with brain gliomas were included. Neurological examination and conventional MRI and DTI scans were performed before and after surgery. Low-grade and high-grade tumors were found in 30% and 70% of patients, respectively. Preoperative DTI demonstrated five patterns of WM tract involvement: non-affected (10%), displaced (75%), edematous (55%), infiltrated (60%), and disrupted (20%). The obtained DTI scans were used for preoperative planning of the surgical corridor and extent of resection to achieve the maximum resection while preserving the WM tracts. Total resection was achieved in 40%, while 60% underwent subtotal resection. Postoperative neurological examination showed deterioration of cognitive function, motor power, and vision in 15%, 10%, and 5% of patients, respectively. Headache persisted in 15%, while motor power improved in 35% of patients. High-grade tumors were significantly associated with higher percentage of subtotal resection (p=0.018) and pattern IV (p=0.018). There was a significant association between the preoperative pattern of WM tract involvement and the postoperative DTI changes (p<0.001).ConclusionDTI enables assessment of displaced and infiltrated WM tracts in the vicinity of brain tumors. Preoperative planning of tumor resection and surgical corridor should include DTI scan to achieve the balance between maximum resection of tumor and maximal preservation of function.

Automatic ocular version evaluation in images using random forest

The version exam is a test performed by specialists in ophthalmology to detect restrictions, paralysis, and disproportionate actions on the eye muscles in binocular movements, which is the simultaneous movement of the eyes. This test is commonly used in the detection, follow-up, and surgical planning of patients with strabismus. Strabismus is a condition in which the eyes do not have adequate alignment, generating several issues not only related to vision but also in social relations. This condition affects approximately 4% of the world’s population. In practice, the version exam is a subjective test, and the creation of a method that aims to automate the examination can help obtain a more objective result. Thus, this work presents an innovative computational method to perform the version examination automatically through face images. The proposed method is organized in seven main steps: (1) image acquisition; (2) preprocessing through a mean filter and Color Badger; (3) eye localization, based on skin segmentation and using Histograms of Oriented Gradients and Random Forest; (4) sclera segmentation, using statistical characteristics and the Random Forest classifier; (5) limbus localization, using as aid the segmented sclera; (6) eye corner localization, based on eye shape, analyzing the inner and outer eyes corners; and (7) version exam, using circle markers for each of the nine eye positions exams. The automatic measurement presented by the method was evaluated through the mean of the difference between the results provided by the method and the original versions measured by the specialist. When considering version, the proposed method obtained a mean accuracy and error of, respectively, 85.18% and 0.29 for the Medial Rectus muscle, 100% and 0 for the Lateral Rectus muscle, 86.9% and 0.47 for the Inferior Oblique muscle, 87.5% and 0.16 for the Superior Rectus muscle, 100% and 0 for the Superior Oblique muscle, and 95.23% and 0.28 for the Inferior Rectus muscle.

Peristapedial bulb: an indicator of spontaneous CSF leak in cochlear candidates with Mondini dysplasia

Background Mondini dysplasia with spontaneous cerebrospinal fluid (CSF) leak is rare in cochlear implantation (CI) candidates but lethal. Detailed evaluation and surgical intervention are needed for these patients. Aim/objective To report our findings of the peristapedial bulb in computer tomography (CT) as diagnostic evidence of spontaneous CSF leak and discuss its clinical value to direct the surgical plan for patients with profound sensorineural hearing loss (SNHL) and meningitis. Material and methods A retrospective review was conducted, including patients’ demographic features, radiographic examination, operation records, auditory/speech evaluation. The patients presented with a peristapedial bulb were included. Results In 2775 CI recipients, 7 out of 219 (3.2%) patients with Mondini anomaly had detectable peristapedial bulbs in HRCT, among whom 6 patients have a history of meningitis. Surgical exploration verified the radiographic findings in 6 out of 7 patients. All patients received CI and vestibular obliteration. Control of meningitis was acceptable. The threshold of hearing significantly decreased from 74.1 dB ± 6.9 dB to 37.1 ± 4.8 dB after CI and the word recognition score elevated from 21.4 ± 14.9% to 78.6 ± 9.3%. Conclusions and significance Peristapedial bulb is an indicator of spontaneous CSF leak in patients with profound SHNL and Mondini anomaly. Patients will benefit from CI and surgical intervention.

Analysis of Actual Versus Predicated Intracranial Volume Changes for Distraction Osteogenesis Using Virtual Surgical Planning in Patients With Craniosynostosis.

The primary outcome metric in patients with craniosynostosis are changes in intracranial volumes (ICVs). In patients who undergo distraction osteogenesis (DO) to treat craniosynostosis, changes are also dependent on the length of distraction. Virtual surgical planning (VSP) has been used to predict anticipated changes in ICV during cranial vault reconstruction. The purpose of this study is to analyze the actual versus predicted ICV changes using VSP in patients who undergo DO for craniosynostosis management. All patients with craniosynostosis treated with DO at a single institution, Rady Children's Hospital, between December 2013 and May 2019 were identified. Inclusion criteria are as follows: VSP planning with predicted postoperative ICV values and preoperative and postdistraction CT scans to quantify ICV. Postoperative ICV and VSP-estimated ICV were adjusted for age-related ICV growth. The primary outcome measure calculated was age-adjusted percent volume change per millimeter distraction (PVCPD), and results were analyzed using paired Wilcoxon signed rank tests. Twenty-seven patients underwent DO for cranial vault remodeling. Nineteen patients were nonsyndromic, and 8 patients were syndromic. The median postoperative PVCPD was 0.30%/mm, and the median VSP-estimated PVCPD was 0.36% per millimeter (P < 0.001). A subanalysis of nonsyndromic patients showed a median postoperative PVCPD of 0.29%/mm in nonsyndromic patients that differed significantly from the VSP estimate of 0.34%/mm (P = 0.003). There was also a significant difference in syndromic patients' observed PVCPD of 0.41%/mm versus VSP estimate of 0.79%/mm (P = 0.012). Virtual surgical planning overestimates the change in ICV attributable to DO in both syndromic and nonsyndromic patients.

Cerebral Anatomy Detection and Surgical Planning in Patients with Anterior Skull Base Meningiomas Using a Virtual Reality Technique.

Anterior skull base meningiomas represent a wide cohort of tumors with different locations, extensions, configurations, and anatomical relationships. Diagnosis of these tumors and review of their therapies are inseparably connected with cranial imaging. We analyzed the influence of three-dimensional-virtual reality (3D-VR) reconstructions versus conventional computed tomography (CT) and magnetic resonance imaging (MRI) images (two-dimensional (2D) and screen 3D) on the identification of anatomical structures and on the surgical planning in patients with anterior skull base meningiomas. Medical files were retrospectively analyzed regarding patient- and disease-related data. Preoperative 2D-CT and 2D-MRI scans were retrospectively reconstructed to 3D-VR images and visualized via VR software to detect the characteristics of tumors. A questionnaire of experienced neurosurgeons evaluated the influence of the VR visualization technique on identification of tumor morphology and relevant anatomy and on surgical strategy. Thirty patients were included and 600 answer sheets were evaluated. The 3D-VR modality significantly influenced the detection of tumor-related anatomical structures (p = 0.002), recommended head positioning (p = 0.005), and surgical approach (p = 0.03). Therefore, the reconstruction of conventional preoperative 2D scans into 3D images and the spatial and anatomical presentation in VR models enabled greater understanding of anatomy and pathology, and thus influenced operation planning and strategy.

Neurovascular networks in epilepsy: Correlating ictal blood perfusion with intracranial electrophysiology

Perfusion patterns observed in Subtraction Ictal SPECT Co-registered to MRI (SISCOM) assist in focus localization and surgical planning for patients with medically intractable focal epilepsy. While the localizing value of SISCOM has been widely investigated, its relationship to the underlying electrophysiology has not been extensively studied and is therefore not well understood. In the present study, we set to investigate this relationship in a cohort of 70 consecutive patients who underwent ictal and interictal SPECT studies and subsequent stereo-electroencephalography (SEEG) monitoring for localization of the epileptogenic focus and surgical intervention. Seizures recorded during SEEG evaluation (SEEG seizures) were matched to semiologically-similar seizures during the preoperative ictal SPECT evaluation (SPECT seizures) by comparing the semiological changes in the course of each seizure. The spectral changes of the ictal SEEG with respect to interictal ones over 7 traditional frequency bands (0.1 to 150Hz) were analyzed at each SEEG site. Neurovascular (SEEG/SPECT) relations were assessed by comparing the estimated spectral power density changes of the SEEG at each site with the perfusion changes (SISCOM z-scores) estimated from the acquired SISCOM map at that site. Across patients, a significant correlation (p<0.05) was observed between spectral changes during the SEEG seizure and SISCOM perfusion z-scores. Brain sites with high perfusion z-score exhibited higher increased SEEG power in theta to ripple frequency bands with concurrent suppression in delta and theta frequency bands compared to regions with lower perfusion z-score. The dynamics of the correlation of SISCOM perfusion and SEEG spectral power from ictal onset to seizure end and immediate postictal period were also derived. Forty-six (46) of the 70 patients underwent resective epilepsy surgery. SISCOM z-score and power increase in beta to ripple frequency bands were significantly higher in resected than non-resected sites in the patients who were seizure-free following surgery. This study provides for the first time concrete evidence that both hyper-perfusion and hypo-perfusion patterns observed in SISCOM maps have strong electrophysiological underpinnings, and that integration of the information from SISCOM and SEEG can shed light on the location and dynamics of the underlying epileptic brain networks, and thus advance our anatomo-electro-clinical understanding and approaches to targeted diagnostic and therapeutic interventions.

How to perform surgical planning for hemodialysis access? Routine preoperative doppler ultrasound mapping

Objectives: The aim of the study was to evaluate the effect of routine preoperative Doppler ultrasound mapping on surgical planning in patients having hemodialysis fistulas. Methods: Patients with arteriovenous fistulas (AVF) or arteriovenous grafts (AVG) were retrospectively reviewed between June 2010 and July 2017. Physical findings, preoperative Doppler ultrasound and postoperative findings of 1924 patients were reviewed. Results: Fistula maturation rate was 82%. The average duration of patency of the first fistula was 19 months (3-38 months) and the duration for a previous fistula operation history was 11 months (1-14 months). Patency rate after 6 months was 78%. Mean maturation times for AVF and AVG were 70 and 28 days, respectively. Doppler ultrasound findings affected operation plans of surgeons in 227 of 908 (25%) first time fistula operation patients, and in 569 of 1016 (56%) patients with previous history of fistula surgery. Review of two groups revealed that Doppler ultrasound affected 41% (796/1924) of fistula planning of surgery for hemodialysis. Conclusions: We suggest that preoperative Doppler ultrasound should be routinely performed in patients undergoing fistulation for hemodialysis. Furthermore, a vascular radiologist and a vascular surgeon should decide the surgical plan together.

Impact of Virtual Reality in Arterial Anatomy Detection and Surgical Planning in Patients with Unruptured Anterior Communicating Artery Aneurysms.

Anterior-communicating artery (ACoA) aneurysms have diverse configurations and anatomical variations. The evaluation and operative treatment of these aneurysms necessitates a perfect surgical strategy based on review of three-dimensional (3D) angioarchitecture using several radiologic imaging methods. We analyzed the influence of 3D virtual reality (VR) reconstructions versus conventional computed tomography angiography (CTA) scans on the identification of vascular anatomy and on surgical planning in patients with unruptured ACoA aneurysms. Medical files were retrospectively analyzed regarding patient- and disease-related data. Preoperative CTA scans were retrospectively reconstructed to 3D-VR images and visualized via VR software to detect the characteristics of unruptured ACoA aneurysms. A questionnaire was used to evaluate the influence of VR on the identification of aneurysm morphology and relevant arterial anatomy and on surgical strategy. Twenty-six patients were included and 520 answer sheets were evaluated. The 3D-VR modality significantly influenced detection of the aneurysm-related vascular structure (p = 0.0001), the recommended head positioning (p = 0.005), and the surgical approach (p = 0.001) in the planning of microsurgical clipping. Thus, reconstruction of conventional preoperative CTA scans into 3D images and the spatial presentation in VR models enabled greater understanding of the anatomy and pathology, provided realistic haptic feedback for aneurysm surgery, and influenced operation planning and strategy.

Doppler Ultrasound as a Unique Diagnosis Test in Peripheral Arterial Disease

The aim of this study was to analyze duplex ultrasound (DUS) and intraoperative angiography concordance for diagnosis of lower limb peripheral artery disease and its value for surgical planning. This was a prospective, observational study, including patients who underwent revascularization of the lower limbs during 2018, diagnosed by DUS only or combined with preoperative computed tomography (CT) angiography. The concordance between preoperative DUS or CT angiography and the intraoperative angiography was studied using the Cohen kappa coefficient (k). The degree of agreement between the DUS-based surgical plan and the final surgical technique was also evaluated. Fifty-one patients were included, with mean age of 71.8±11.96years (46-94); 23 had chronic kidney disease (45%). In 17 patients (34%), preoperative CT angiography was also performed. DUS showed a sensitivity of 100% (95% confidence interval (CI) [83.3-100%]), 80% (95% CI [50.21-100%,]), and 100% (95% CI [96.43-100%]) at the iliac, femoral, and popliteal sector, respectively, and a specificity of 93.55% (95% CI [83.29-100%]), 95.45% (95% CI [84.48-100%]), and 90.48% (95% CI [75.54-100%]) at the iliac, femoral, and popliteal sector, respectively. The positive predictive value for DUS was 60% (95% CI [7.06-100%]), 88.9% (95% CI [62.8-100%]), and 87.5% (95% CI [68.17-100%]) for the iliac, femoral, and popliteal sectors, respectively, whereas the negative predictive value was 100% (95% CI [98.28-100%]), 91.3% (95% CI [77.61-100%]), and 100% (95% CI, [97.37-100%]). The concordance between DUS and intraoperative angiography showed a k index of 0.587 (P=0.000) in the iliac sector, 0.799 in the femoral sector (P=0.000), and 0.699 in the popliteal sector (P=0.000). The concordance between CT angiography/intraoperative angiography had a k index of 0.71 in the iliac sector (P=0.0093), 0.566 in the femoral sector (P=0.006), and 0.5 in the popliteal sector (P=0.028). DUS-based surgical plan was accurate in 86% of cases (n=44). Our experience suggests that DUS arterial mapping of the femoral and popliteal areas is better than CT angiography and can be considered as a unique preoperative imaging test during the surgical planning in patients undergoing a lower limb revascularization procedure.

Contribution of Ictal Source Imaging for Localizing Seizure Onset Zone in Patients With Focal Epilepsy

To determine whether seizure onset zone (SOZ) can be localized accurately prior to surgical planning in patients with focal epilepsy, we performed noninvasive EEG recordings and source localization analyses on 39 patients. In 39 patients with focal epilepsy, we recorded and extracted 138 seizures and 1,325 interictal epileptic discharges using high-density EEG. We investigated a novel approach for directly imaging sources of seizures and interictal spikes from high-density EEG recordings, and rigorously validated it for noninvasive localization of SOZ determined from intracranial EEG findings and surgical resection volume. Conventional source imaging analyses were also performed for comparison. Ictal source imaging showed a concordance rate of 95% when compared to intracranial EEG or resection results. The average distance from estimation to seizure onset (intracranial) electrodes is 1.35 cm in patients with concordant results, and 0.74 cm to surgical resection boundary in patients with successful surgery. About 41% of the patients were found to have multiple types of interictal activities; coincidentally, a lower concordance rate and a significantly worse performance in localizing SOZ were observed in these patients. Noninvasive ictal source imaging with high-density EEG recording can provide highly concordant results with clinical decisions obtained by invasive monitoring or confirmed by resective surgery. By means of direct seizure imaging using high-density scalp EEG recordings, the added value of ictal source imaging is particularly high in patients with complex interictal activity patterns, who may represent the most challenging cases with poor prognosis.

Current Concepts Regarding Patellofemoral Trochlear Dysplasia

Optimal treatment of patients with patellofemoral trochlear dysplasia and recurrent patellar instability requires in-depth understanding of this complex structural anomaly. An extensive review of the literature suggests that dysplasia occurs as a result of aberrant forces applied to the patellofemoral joint in the majority of cases. Evidence supports surgical stabilization that reconstructs the medial patellofemoral and/or medial quadriceps tendon–femoral ligament without added trochleoplasty in the majority of patients with trochlear dysplasia and recurrent patellar instability. Adding tibial tubercle transfer distally, medially, or anteromedially in those who need it to treat specific deficits in alignment or articular cartilage can be beneficial in selected patients with trochlear dysplasia and recurrent patellar instability. Trochleoplasty may be appropriate in those few cases in which permanent stable patellofemoral tracking cannot be restored otherwise, but the indications are not yet clear, particularly as trochleoplasty adds risk to the articular cartilage. Improved understanding of imaging techniques and 3-dimensional reproductions of dysplastic patellofemoral joints are useful in surgical planning for patients with recurrent patellar instability and trochlear dysplasia.

Use of imaging as staging and surgical planning for pancreatic surgery.

In the past few decades, there has been rapid advancements in imaging technologies that have become irreplaceable in the pre-operative assessment of patients with pancreatic tumors. Modern imaging modalities, including computed tomography (CT) and endoscopic ultrasound (EUS), can provide critical information of the absence or presence of metastatic disease in pancreatic cancer, as well as details on the local extent and resectability, allowing for the selection of stage appropriate treatments and pre-operatively determined surgical approach. The aim of this review is to discuss staging, resectability, and imaging for patients with pancreatic tumors. A literature review was performed of articles relevant to the topics of staging, resectability, and imaging of pancreatic tumors. Imaging modalities included CT, EUS, magnetic resonance imaging (MRI), positron emission tomography (PET), antibody-based and narrow band imaging. CT pancreas protocol combined with EUS serve as the primary modalities in diagnosis, staging, and surgical planning in patients with pancreatic tumors. MRI is an alternative to CT with near equivalent utility in the pre-operative setting. In some circumstances, PET-CT may be a cost-effective initial study to detect distant disease. Current imaging technologies play a critical role in the evaluation of patients with pancreatic tumors. Advances in the past 3 decades in imaging technologies have revolutionized the process of assessment of stage and resectability in patients with pancreatic tumors. Future imaging technologies will address current limitation in the evaluation of occult metastatic disease.

Cervical and ocular vestibular evoked myogenic potentials in determining nerve division involvement in patients with a tumor located in the internal auditory canal

ObjectivesThe study aimed at the analysis of the parameters of acoustic cervical and ocular vestibular evoked myogenic potentials (AC-cVEMP and AC-oVEMP) response in patients with a confirmed tumor located in the internal auditory canal. It also aimed to assess to what degree a combination of these tests may be of benefit in the preoperative indication of the affected nerve division via preoperative determination whether the tumor originated from the superior or inferior division of the vestibular nerve, both divisions, or if it originated from a different nerve in the internal auditory canal. MethodsThe study group included 50 patients. Preoperative MRI scans were used to measure tumor diameter. AC-cVEMP and AC-oVEMP testing were performed before tumor resection. The surgeon was asked for a detailed description of the tumor origin. ResultsThe corrected amplitude of cVEMP was significantly lower on the tumor side than on the non-affected side and in the control group. The corrected Asymmetry Ratio (AR) of cVEMPs in patients with the tumor was significantly elevated above the reference values with the mean being 58.29% and the mean AR of oVEMPs in patients the tumor was 71.78% which made both results significantly higher than in the control group. Neither cVEMP nor oVEMP latency was significantly correlated with tumor size. Data obtained from cVEMP and oVEMP tests was an effective indicator of tumor origin in 74% of patients showing which division (or both divisions) of the VIIIth nerve was affected in comparison with information obtained from the surgeon. ConclusionsThe combined use of AC-cVEMP and AC-oVEMP tests may be useful in surgical planning in patients the tumor located in the internal auditory canal, providing a highly probable determination of the division of the affected nerve. Such information is valuable for the surgeon as it offers additional knowledge about the tumor before the procedure. cVEMP and oVEMP results may not be used as the basis for the calculation of tumor size in patients.

Magnetic resonance angiography (MRA) in preoperative planning for patients with 22q11.2 deletion syndrome undergoing craniofacial and otorhinolaryngologic procedures

IntroductionPatients with 22q11.2 deletion syndrome (22q11.2DS) have a variety of anatomic anomalies. For surgeons operating in proximity to the retropharynx, the most pertinent is medial displacement of the internal carotid arteries. The purpose of this study is to describe the preoperative use of magnetic resonance angiography (MRA) in surgical planning and update the incidence rate of medial carotid displacement in patients with 22q11.2DS. MethodsThis is a retrospective cohort study of patients with a confirmed diagnosis of 22q11.2 deletion and preoperative MRA <18 years old who underwent tonsillectomy, adenoidectomy, Furlow palatoplasty (FPP), posterior pharyngeal flap (PPF), sphincter pharyngoplasty (SPP), or submucosal cleft palate (SMCP) repair between January 1st, 2008 and December 31st, 2019. ResultsNinety patients who met the inclusion criteria underwent 133 procedures. The majority identified as Caucasian (84.4%); 52.2% were female. Cervical MRA was more likely to be ordered before a PPF (80.9%) and tonsillectomy (72.7%) over a FPP (47.6%) or adenoidectomy (11.1%). Carotid medialization was visualized in 23 patients (25.6%) and was mild in 11 cases, moderate in 7 cases, and significant in 5 cases. There was no association between sex, race/ethnicity, or genetic diagnosis with carotid medialization. Flap shortening was necessary in 20% of PPF cases to avoid injuring the medialized vessel. ConclusionPatients with 22q11.2DS may have higher rates of medialization of the carotid arteries than previously thought. Given the risk for complications in these patients during pharyngeal operations, there may be a critical place for MRA in surgical planning for patients with 22q11.2DS.

Recurrent Tube Erosions with Anti-Vascular Endothelial Growth Factor Therapy in Patients with Age-Related Macular Degeneration

To determine the rates of primary and recurrent glaucoma tube shunt erosions in patients with age-related macular degeneration (AMD) receiving anti-vascular endothelial growth factor (VEGF) intravitreal injections. Retrospective case series. Patients with AMD who underwent tube revision for erosion at the Duke Eye Center from January 1, 1999, to January 1, 2019, were identified. Patients with and without anti-VEGF injections were compared. Patient demographics, ocular diagnoses, glaucoma tube shunt types and locations, and dates of glaucoma surgeries and anti-VEGF injections were collected. Statistical analyses were performed with P < 0.05 as significant. Outcome measures included the number of tube erosions, time from anti-VEGF injection to tube erosion, and secondary complications after tube revisions. A total of 150 patients with AMD with anti-VEGF (309 tubes) and 262 patients with AMD without anti-VEGF (459 tubes) were identified. There was no statistically significant difference in the number of tube erosions in patients with anti-VEGF (15 tubes, 4.8%) versus without anti-VEGF (12 tubes, 2.6%) (P= 0.10). However, patients receiving anti-VEGF had on average a greater number of tube erosion events (2.1±0.7 events) compared with patients without anti-VEGF (1.3±0.7, P < 0.01). Ten patients (91%) received concurrent anti-VEGF injections at the time of tube erosion, and the average duration of prior anti-VEGF therapy was approximately 2 years. Tube erosion was noted 46.5±60.7 days from the preceding anti-VEGF injection. Secondary complications after tube revision in the anti-VEGF group included 5 explanted tubes for recurrent erosions. Our results suggest intravitreal anti-VEGF injections are linked to higher rates of recurrent glaucoma tube erosions in patients with AMD. The majority of patients received chronic and serial anti-VEGF injections. Thus, additional consideration should be given to glaucoma surgical planning in patients receiving anti-VEGF injections, especially in those with a primary tube erosion.