Presurgical Computed Tomography Research Articles

Neurogenic heterotopic ossification of the hip: Magnetic resonance imaging versus computed tomography for pre-surgical assessment

PurposeNeurogenic heterotopic ossification (NHO) of the hip is a frequent complication of spinal cord injuries, often requiring surgical management. Pre-surgical imaging assessment is essential, usually with computed tomography (CT)-scan. We aimed to compare magnetic resonance imaging (MRI) and CT for pre-surgical imaging assessment of the NHO, particularly for their relationships with vessels and nerves. MethodThis prospective study included consecutive patients who underwent surgery for NHO from July 2019 to April 2022. All patients had CT angiography and MRI including Zero Echo Time and TRICKS sequences. Radiologists used standardized reports for CT and MRI to evaluate NHO and their features, bone mineralization, and relation to the arteries, veins and nerves. Agreement between pre-surgical CT and MRI was evaluated. ResultsTwenty-four patients (mean age: 53.5 ± 12.2 years) were included, among which 7 had bilateral NHO (31 hips). NHO were anterior in 15/31 hips (48 %), multifragmented in 25/31 hips (81 %). Mild and significant demineralization was most frequent. Gutter and tunnel were reported in 11.1 % of the arteries. Nerves were more often identified in MRI than in CT-scan. Agreement coefficients between CT and MRI were excellent for NHO location (0.95) and implantation (0.92), good for fragmentation (0.70), contact with joint capsule (0.66), bone mineralization (0.74), and relation to arteries (0.85), veins (0.76), sciatic nerve (0.7) and moderate for femoral nerve (0.47). ConclusionMRI exhibited a good agreement with CT for pre-surgical assessment of NHO of the hip, especially to evaluate their relationships with the arteries, veins and sciatic nerve. Femoral nerves were more often identified in MRI than in CT-scan.

Skeletal muscle and visceral adipose radiodensities are pre-surgical, non-invasive markers of aggressive kidney cancer.

Most studies on body composition in kidney cancer have been conducted among patients with metastatic disease. Given that aggressive tumours can adversely impact body composition and even non-metastatic tumours can be aggressive, we evaluated associations between pre-surgical body composition features and tumour pathological features in patients with non-metastatic clear cell renal cell cancer (ccRCC). The Resolve Cohort consists of 1239 patients with non-metastatic ccRCC who underwent nephrectomy at Memorial Sloan Kettering Cancer Center between 2000 and 2020. The cross-sectional areas and radiodensities of skeletal muscle, visceral adipose, and subcutaneous adipose tissues were determined from pre-surgical computed tomography (CT) scans at the third lumbar vertebrae using Automatica software. Pearson's correlation coefficients describe inter-relationships among BMI and body composition variables, while odds ratios (OR) and 95% confidence intervals (CI) estimate associations between continuous body composition features (per 1-standard deviation) and advanced stage (Stage III vs. Stages I-II) and high Fuhrman grade (Grades 3-4 vs. 1-2) from multivariable logistic regression models that considered the potential impact of biological sex, contrast enhanced CTs, and early age at onset of ccRCC. The cohort was predominantly male (69%), white (89%), and had a median age of 58. The proportion of patients presenting with advanced stage and high-grade disease were 31% and 51%, respectively. In models that adjusted for demographics and all body composition variables simultaneously, decreasing skeletal muscle radiodensity (i.e., more fat infiltration) but increasing visceral adipose tissue radiodensity (i.e., more lipid depletion) were associated with advanced tumour features. Per 8.4 HU decrease in skeletal muscle radiodensity, the odds of presenting with advanced stage was 1.61 (95% CI: 1.34-1.93). Per 7.22 HU increase in visceral adipose tissue radiodensity, the odds of presenting with advanced stage was 1.45 (95% CI: 1.22-1.74). Skeletal muscle index (i.e., sarcopenia) was not associated with either tumour feature. Similar associations were observed for Fuhrman grade, a more direct marker of tumour aggressiveness. Associations did not differ by sex, contrast use, or age at onset of ccRCC. Lipid infiltrated skeletal muscle, but lipid depleted visceral adipose tissue were independently associated with advanced tumour features in non-metastatic ccRCC. Findings highlight the importance of evaluating the full range of body composition features simultaneously in multivariable models. Interpreting pre-surgical CTs for body composition for patients may be a novel and non-invasive way to identify patients with aggressive renal tumours, which is clinically relevant as renal biopsies are not routinely performed.

Limited impact of discretization/interpolation parameters on the predictive power of CT radiomic features in a surgical cohort of pancreatic cancer patients.

To explore the variation of the discriminative power of CT (Computed Tomography) radiomic features (RF) against image discretization/interpolation in predicting early distant relapses (EDR) after upfront surgery. Data of 144 patients with pre-surgical high contrast CT were processed consistently with IBSI (Image Biomarker Standardization Initiative) guidelines. Image interpolation/discretization parameters were intentionally changed, including cubic voxel size (0.21-27 mm3) and binning (32-128 grey levels) in a 15 parameter's sets. After excluding RF with poor inter-observer delineation agreement (ICC < 0.80) and not negligible inter-scanner variability, the variation of 80 RF against discretization/interpolation was first quantified. Then, their ability in classifying patients with early distant relapses (EDR, < 10months, previously assessed at the first quartile value of time-to-relapse) was investigated in terms of AUC (Area Under Curve) variation for those RF significantly associated to EDR. Despite RF variability against discretization/interpolation parameters was large and only 30/80 RF showed %COV < 20 (%COV = 100*STDEV/MEAN), AUC changes were relatively limited: for 30 RF significantly associated with EDR (AUC values around 0.60-0.70), the mean values of SD of AUC variability and AUC range were 0.02 and 0.05 respectively. AUC ranges were between 0.00 and 0.11, with values ≤ 0.05 in 16/30 RF. These variations were further reduced when excluding the extreme values of 32 and 128 for grey levels (Average AUC range 0.04, with values between 0.00 and 0.08). The discriminative power of CT RF in the prediction of EDR after upfront surgery for pancreatic cancer is relatively invariant against image interpolation/discretization within a large range of voxel sizes and binning.

Maximum Diameter of the Gallbladder Determined Presurgically Using Computed Tomography as a Risk Factor for Difficult Emergency Laparoscopic Cholecystectomy in Patients With Mild to Moderate Acute Cholecystitis.

Early or emergency laparoscopic cholecystectomy (LC) was recommended in the 2018 Tokyo Guidelines for patients with mild to moderate acute cholecystitis (AC). Although surgical difficulty is frequently encountered during these surgeries, risk factors for predicting surgical difficulties have not been fully investigated, especially based on computed tomography (CT) findings. We investigated 72 patients who underwent emergency LC with mild (n=45) to moderate (n=27) AC. Patients who previously underwent presurgical percutaneous or endoscopic biliary drainage were excluded from this study. Difficult LC was defined using any of the following surgical factors: surgical duration ≥180 minutes, blood loss ≥300g, or a conversion to open cholecystectomy. Subsequently, several presurgical clinical factors were analyzed, including sex, age at surgery, experience of the surgeon, interval between symptom onset and surgery, body mass index, diabetes history, presurgical white blood cell count, and C-reactive protein level. Moreover, stones in the cystic duct or perigallblader fluid and the maximum thickness and diameter of the gallbladders were evaluated via presurgical CT. Finally, logistic regression analysis was performed to compare the relationship between surgical difficulty and each clinical factor. The average age at surgery of the included patients was 60.3 (range: 25 to 88y), surgical duration was 112.2 (range: 29 to 296min), and surgical blood loss was 55.2 (range: 0 to 530g). Furthermore, 4 (5.6%) had to undergo open cholecystectomy, whereas postsurgical complications occurred in 5 (6.9%) patients. In addition, the mean postsurgical admission duration was 7 (range: 3 to 63d). Thus, 12 patients experienced difficult LC, whereas 60 experienced nondifficult LC. Of the evaluated clinical factors, patients who experienced difficult LC showed higher presurgical C-reactive protein levels (10.78 vs. 6.76mg/dL, P =0.01) and wider gallbladder diameters (48.4 vs. 41.8mm, P <0.01) than those who experienced nondifficult LC. By univariate logistic regression analysis, results also showed that patients with a maximum gallbladder diameter had a higher risk of experiencing difficulty during emergency LC ( P =0.02). Moreover, the gallbladder diameter's cutoff value was 43mm after the receiver operating characteristic curve analysis. In patients with mild to moderate AC, emergency LC can safely be performed. However, performing LC might be technically difficult in patients with AC after the identification of severe gallbladder swelling during presurgical CT.

Automatic 3-Dimensional Cephalometric Landmarking via Deep Learning

The increasing use of 3-dimensional (3D) imaging by orthodontists and maxillofacial surgeons to assess complex dentofacial deformities and plan orthognathic surgeries implies a critical need for 3D cephalometric analysis. Although promising methods were suggested to localize 3D landmarks automatically, concerns about robustness and generalizability restrain their clinical use. Consequently, highly trained operators remain needed to perform manual landmarking. In this retrospective diagnostic study, we aimed to train and evaluate a deep learning (DL) pipeline based on SpatialConfiguration-Net for automatic localization of 3D cephalometric landmarks on computed tomography (CT) scans. A retrospective sample of consecutive presurgical CT scans was randomly distributed between a training/validation set (n = 160) and a test set (n = 38). The reference data consisted of 33 landmarks, manually localized once by 1 operator(n = 178) or twice by 3 operators (n = 20, test set only). After inference on the test set, 1 CT scan showed “very low” confidence level predictions; we excluded it from the overall analysis but still assessed and discussed the corresponding results. The model performance was evaluated by comparing the predictions with the reference data; the outcome set included localization accuracy, cephalometric measurements, and comparison to manual landmarking reproducibility. On the hold-out test set, the mean localization error was 1.0 ± 1.3 mm, while success detection rates for 2.0, 2.5, and 3.0 mm were 90.4%, 93.6%, and 95.4%, respectively. Mean errors were −0.3 ± 1.3° and −0.1 ± 0.7 mm for angular and linear measurements, respectively. When compared to manual reproducibility, the measurements were within the Bland–Altman 95% limits of agreement for 91.9% and 71.8% of skeletal and dentoalveolar variables, respectively. To conclude, while our DL method still requires improvement, it provided highly accurate 3D landmark localization on a challenging test set, with a reliability for skeletal evaluation on par with what clinicians obtain.

Preoperative diagnosis of obstructive colitis in colorectal cancer patients who underwent self-expandable metallic stent insertion as a bridge to surgery

PurposeObstructive colitis (OC) is a risk factor of anastomotic leakage in colorectal cancer resection. We aimed to clarify the relationship between the severity of OC and clinicopathological findings and to detect predictive factors of OC. MethodsWe retrospectively reviewed 43 cases of colectomy after self-expandable metallic stent placement for left-sided colorectal cancer. Preoperative diagnosis of OC was made by multiple modalities (initial computed tomography (CT), presurgical CT, and colonoscopy). We classified OC macroscopically in resected specimens into five groups (Grade 0: none, 1: mild [mild edema], 2: moderate [severe edema, redness, erosion], 3: severe [ulceration, bleeding], 4: very severe [necrosis, perforation]), and investigated the relationship between the preoperative assessment, surgical findings and the severity of OC. ResultsOC of Grade 2 or more (53.5%) was significantly correlated with severe edema in initial CT. There was no significant correlation between OC and anastomosis rate. The creation of covering stoma was significantly higher in the Grade 2 or more OC group. No leakage was observed in either group. ConclusionsInitial CT may be most useful for prediction of OC. It is important to make a preoperative diagnosis of OC by combining multiple modalities, which enables to determine the appropriate location for resection, anastomosis, and construction of a covering stoma.

Diagnostic Performance of MRI Versus CT in the Evaluation of Intra-articular Osteochondral Fracture in Pediatric Patients With Acute Traumatic Lateral Patellar Dislocation.

Background:Evaluation of intra-articular osteochondral fractures in children with acute traumatic lateral patellar dislocation (LPD) is important for determining treatment options.Purpose:To (1) compare the diagnostic accuracy of computed tomography (CT) and magnetic resonance imaging (MRI) for evaluating intra-articular osteochondral fractures; (2) compare the interpretation of CT and MRI images between radiologists and pediatric orthopaedic surgeons (POS); and (3) investigate any clinical factors influencing the accuracy of CT and MRI evaluations.Study Design:Cohort study (diagnosis); Level of evidence, 2.Methods:We reviewed 35 knees in 35 patients (mean age, 12.2 ± 1.2 years; 12 boys and 23 girls) who were treated arthroscopically for acute traumatic LPD; 71% of the patients had patellar fractures, 54% had femoral fractures, and 60% had free osteochondral fracture fragments. All presurgical MRI and CT images were reviewed by POS who were blinded to both the reports of the radiologists and surgical records. We compared the accuracy of CT and MRI in diagnosing intra-articular osteochondral fractures against the arthroscopic findings and compared the interpretation of the images by the POS (MRI-O, CT-O) with those of the radiologists (MRI-R, CT-R).Results:There was no significant difference in diagnostic accuracy between CT and MRI for overall intra-articular osteochondral fractures by the POS or the radiologists; however, the CT-O images had a higher diagnostic specificity (84.2% vs 69.6%; P < .001) and sensitivity (88.1% vs 70.1%; P < .001) versus the MRI-R images. Regarding free fracture fragments, the CT-R images had a higher diagnostic accuracy than the MRI-R images (73.5% vs 47.1%; P = .026). When backed by clinical data, the MRI-O images had greater diagnostic accuracy (78.7% vs 60.3%; P = .001) and sensitivity (88.1% vs 30.7%; P = .021) but lower specificity compared with the MRI-R images, and the CT-O images had similar diagnostic accuracy but greater sensitivity than the CT-R images (70.1% vs 52.2%; P < .001). The diagnostic accuracy of MRI-O images was lower for children under 12 years versus children 12 years and over (67.5% vs 83.3%; P = .040).Conclusion:Compared with MRI, CT scans had better diagnostic performance in the evaluation of intra-articular osteochondral fractures in pediatric patients with acute traumatic LPD. Clinical data enhanced the diagnostic sensitivity of MRI and CT but decreased the specificity of MRI. MRI evaluations remain challenging for both POS and radiologists.

Diagnostic prediction of complicated appendicitis by combined clinical and radiological appendicitis severity index (APSI).

To develop a routinely applicable severity index for the management of acute appendicitis in adults using combined clinical and radiological parameters and retroperitoneal space planes (RSP). Two hundred consecutive patients with histologically proven acute appendicitis and available presurgical CT scans were analysed retrospectively. Two radiologists assessed all CT scans for morphologic sings of appendicitis and six RSP. Clinical parameters were age, body temperature, C-reactive protein (CRP), white blood cell count, and duration of symptoms. Radiological parameters were appendix diameter and wall thickness, periappendiceal fat stranding and fluid, intraluminal and extraluminal air, thinning of appendiceal wall, caecal wall thickening, appendicolith and abscess formation. One hundred and three patients (51%) had histologically proven complicated appendicitis. Based on three clinical (age ≥52 years, body temperature ≥37.5°C, duration of symptoms ≥48 h) and four computed tomography (CT) findings (appendix diameter ≥14 mm, presence of periappendiceal fluid, extraluminal air, perityphlitic abscess), the APSI was developed using regression coefficients of multivariate logistic regression analyses with a maximum of 10 points. A score of ≥4 points predicted complicated appendicitis with a positive predictive value of 92% and a negative predictive value of 83%. Substantial to excellent interobserver agreement was found for the four radiological parameters of the APSI [intraclass correlation coefficient (ICC), 0.78-0.83]. The RSP evaluation presented no added value for the diagnosis of complicated appendicitis. Using APSI, an accurate and simple prediction of complicated appendicitis in adults was possible. The RSP count was not useful for the diagnosis of complicated appendicitis. • Appendicitis severity score provides an accurate and simple prediction of complicated appendicitis • Appendicitis severity score ≥4 accurately predicted complicated appendicitis (PPV 92%;NPV 83%) • Evaluation of retroperitoneal space planes was not useful in diagnosing complicated appendicitis.

Intrahepatic cholangiocarcinoma: can imaging phenotypes predict survival and tumor genetics?

On computed tomography (CT), intrahepatic cholangiocarcinomas (ICC) are a visibly heterogeneous group of tumors. The purpose of this study was to investigate the associations between CT imaging phenotypes, patient survival, and known genetic markers. A retrospective study was performed with 66 patients with surgically resected ICC. Pre-surgical CT images of ICC were assessed by radiologists blinded to tumor genetics and patient clinical data. Associations between qualitative imaging features and overall survival (OS) and disease-free survival (DFS) were performed with Cox proportional hazards regression and visualized with Kaplan-Meier plots. Associations between radiographic features and genetic pathways (IDH1, Chromatin and RAS-MAPK) were assessed with Fisher's Exact test and the Wilcoxon Rank sum test where appropriate and corrected for multiple comparisons within each pathway using the False Discovery Rate correction. Three imaging features were significantly associated with a higher risk of death: necrosis (hazard ratio (HR) 2.95 95% CI 1.44-6.04, p=0.029), satellite nodules (HR 3.29, 95% CI:1.35-8.02, p=0.029), and vascular encasement (HR 2.63, 95% CI 1.28-5.41, p=0.029). Additionally, with each increase in axial size, the risk of death increased (HR 1.14, 95% CI 1.03-1.26, p=0.029). Similar to findings for OS, satellite nodules (HR 3.81, 95% CI 1.88-7.71, p=0.002) and vascular encasement (HR 2.25, 95% CI 1.24-4.06, p=0.019) were associated with increased risk of recurrence/death. No significant associations were found between radiographic features and genes in the IDH1, Chromatin or RAS-MAPK pathways (p=0.63-84). This preliminary analysis of resected ICC suggests associations between CT imaging features and OS and DFS. No association was identified between imaging features and currently known genetic pathways.

The Role of Fluorodeoxy-D-glucose Positron Emission Tomography/Computed Tomography in Nodal Staging of Nonsmall Cell Lung Cancer in Sequential Surgical Algorithm.

With nonsmall cell lung cancer (NSCLC), accurate mediastinal nodal staging is crucial to determine whether a patient is or is not a surgical candidate. Traditionally, computed tomography (CT) and fluorodeoxy-D-glucose (FDG) positron emission tomography (PET)/CT are the initial steps followed by tissue sampling through mediastinoscopy and/or thoracotomy, which are invasive procedures. There is controversy regarding the possibility of omission of the invasive diagnostic procedures and solely relying on noninvasive presurgical staging CT and FDG PET/CT results. Eighty-three patients who had PET/CT, mediastinoscopy, and thoracotomy for NSCLC were analyzed. For all lymph nodes that may be sampled by mediastinoscopy, PET/CT sensitivity was 80%, specificity was 86%, positive predictive value was 47%, and negative predictive value (NPV) was 97%; and for those in this group whose clinical stage was T1/T2 M0, sensitivity was 100% and specificity was 84%. For lymph nodes accessible only at thoracotomy, sensitivity was 42% and specificity was 88%. FDG PET/CT is accurate in assessing stations 2R/L, 4R/L, and 7 nodes and has the potential to replace mediastinoscopy in the treatment algorithm of T1/T2 M0 disease. A negative PET/CT may potentially prevent the patient from invasive mediastinoscopy given its high NPV. However, a patient with positive PET/CT should undergo tissue biopsy with pathology confirmation.

Noninvasive screening test for detecting early stage lymphedema using follow-up computed tomography imaging after cancer treatment and results of treatment with lymphaticovenular anastomosis.

Although early detection is valuable for secondary lymphedema treatment, existing screening tests are not popular. This study aimed to propose a novel method of screening lymphedema patients based on the thickness of the subcutaneous fat measured with perioperative computed tomography (CT) and present the results from evaluation of patients who underwent those examinations was performed. The medical records of 96 gynecological cancer patients and 189 breast cancer patients, whose lymphatic function was assessed with indocyanine green lymphography, were reviewed. In gynecological cancer patients, the perioperative temporal subcutaneous fat thickness index (T-SFTI) was calculated from presurgical and follow-up CT data, and in breast cancer patients, the postoperative crosswise subcutaneous fat thickness index (C-SFTI) was calculated. In lower extremity lymphedema patients, the effect of lymphaticovenular anastomosis (LVA) was also evaluated using T-SFTI. Perioperative T-SFTI was assessed in 180 lower extremities, and it was significantly higher in 46 lymphatic dysfunction limbs (1.21 ± 0.08) than in 134 normal lymphatic function limbs (1.03 ± 0.08), (P < .01). Postoperative C-SFTI was assessed in 53 upper extremity, and it was significantly higher in 11 lymphatic dysfunction limbs (1.31 ± 0.21) than in 42 normal lymphatic function limbs (1.01 ± 0.06), (P < .01). In lower extremity lymphedema patients, T-SFTI improved significantly after planned conservative treatments and LVA (P = .04). Assessment of subcutaneous fat thickness using CT is useful for screening early stage lymphedema. If the efficacy of this method is validated, patients worldwide may be assessed using the same criterion.

CT evaluation after neoadjuvant FOLFIRINOX chemotherapy for borderline and locally advanced pancreatic adenocarcinoma.

To assess anatomic changes on computed tomography (CT) after neoadjuvant FOLFIRINOX (5-fluorouracil/leucovorin/irinotecan/oxaliplatin) chemotherapy for secondary resected borderline resectable (BR) and locally advanced (LA) pancreatic adenocarcinoma and their accuracy to predict resectability and pathological response. Thirty-six patients with secondary resected BR/LA pancreatic adenocarcinoma after neoadjuvant FOLFIRINOX chemotherapy (± chemoradiotherapy) were retrospectively included. Two radiologists reviewed baseline and pre-surgical CTs in consensus. NCCN (National Comprehensive Cancer Network) classification, largest axis, product of the three axes (P3A), and arterial/venous involvement were studied and compared to pathological response and resection status and to disease-free survival (DFS). Thirty-one patients had R0 resection, including only six exhibiting a downstaging according to the NCCN classification. After treatment, the largest axis and P3A decreased (P < 0.0001). The pre-surgical largest axis and P3A were smaller in case of R0 resection (P = 0.019/P = 0.021). The largest axis/P3A variations were higher in case of complete pathological response (P = 0.011/P = 0.016). A decrease of the arterial/venous involvement was not able to predict R0 or ypT0N0 (P > 0.05). Progression of the vascular involvement was seen in two (5%) patients and led to a shorter DFS. In BR/LA pancreatic adenocarcinoma after the neoadjuvant FOLFIRINOX regimen (± chemoradiotherapy), significant tumour size decreases were observed on CT. However, CT staging was not predictive of resectability and pathological response. • Significant tumour size decreases were observed on CT after FOLFIRINOX (± chemoradiotherapy). • CT is not able to predict R0 resection accurately after FOLFIRINOX (± chemoradiotherapy). • CT is not able to predict complete response accurately after FOLFIRINOX (± chemoradiotherapy). • Even with a stable NCCN classification, BR/LA pancreatic adenocarcinoma could have R0 resection.

New Radiologic Parameters Predict Clinical Outcome after Decompressive Craniectomy

Decompressive craniectomy (DC) is an established part of the management of patients with increased intracranial pressure due to malignant middle cerebral artery (MCA) infarction or traumatic brain injury (TBI). The aim of this study was to determine prognostic radiologic parameters regarding the functional outcome of patients with increased intracranial pressure (ICP) undergoing DC. Special focus was put on the potential differences between malignant MCA infarction and TBI. A total of 113 patients were analyzed for their clinical course where preoperative and postoperative radiologic features in computed tomography (CT) scans were correlated to the clinical outcome assessed by the Glasgow Outcome Scale. The difference between presurgical and postsurgical midline shift (ΔMLS) and the ratio between the diameter of the affected and contralateral hemisphere (HDratio) in presurgical and postsurgical CT scans were calculated. ΔMLS (MCA infarction group) and postsurgical HDratio (TBI group) were found to be highly correlating with the clinical outcome on Spearman-correlation testing and underwent further analysis using a binary logistic regression model to evaluate their prognostic value on the outcome, which showed the predictive power of ΔMLS in malignant MCA infarction patients (odds ratio [OR] 0.715; confidence interval [CI] 0.551-0.865). Postsurgical HDratio correlated significantly (OR 0.620; CI 0.384-0.901) with the outcome in the TBI group. ΔMLS is an objectifiable parameter, predicting outcome in malignant MCA infarction. In contrast, ΔMLS was of no predictive value in TBI patients. Here postsurgical HDratio serves as a strong predictor of clinical outcome. We recommend applying postsurgical HDratio to TBI patients in order to estimate their clinical outcome and adjust treatment.

Structured Reporting of Multiphasic CT for Pancreatic Cancer: Potential Effect on Staging and Surgical Planning

To compare structured versus nonstructured reporting of multiphasic computed tomography (CT) for staging of pancreatic cancer and the effects of both types of reporting on subjective assessment of resectability. This institutional review board-approved, HIPAA-compliant retrospective study with waiver of informed consent included all patients who were referred for presurgical multiphasic CT of the pancreas between December 2006 and April 2011 at one institution before and after implementation (April 2008) of a structured reporting template. The template was created specifically for reporting multiphasic CT results to stage pancreatic cancer in patients and contained specific information relevant to surgical and oncologic planning. Multiphasic CT reports were assessed for the presence of 12 key features required for staging and surgical planning, including location, size, enhancement, node status, and vascular involvement. Three pancreatic surgeons evaluated the reports to assess resectability, surgical planning, and ease of extracting information before and after reviewing the multiphasic CT images blinded to the patient identifiers. The Student t test and χ(2) test were used for statistical analysis. Forty-eight (40%) structured and 72 (60%) nonstructured multiphasic CT reports were reviewed. Nonstructured reports contained a mean ± standard deviation of 7.3 key features ± 2.1 (range, 1-11) and structured reports contained 10.6 ± 0.9 (range, 9-12) features (P < .001). Information for surgical planning was deemed easily accessible in 94%, 60%, and 98% of structured and 47%, 54%, and 32% of nonstructured reports by the three surgeons, respectively (P < .001, .79, < .001). Surgeons had sufficient information for surgical planning in 96%, 69%, and 98% of structured and 31%, 43%, and 25% of nonstructured reports (P < .001, .009, and < .001). When surgeons reviewed reports in combination with multiphasic CT images, they were more likely to convert an answer of "unsure" regarding resectability to a definitive answer (ie, resectable or unresectable) when the reports were structured than when they were nonstructured. Structured reporting of pancreatic multiphasic CT provided superior evaluation of pancreatic cancer and facilitated surgical planning. Surgeons were more confident regarding decisions about tumor resectability when they reviewed structured reports before review of multiphasic CT images.

Current Computed Tomography Techniques Can Detect Duct of Bellini Plugging but Not Randall's Plaques

To assess the ability of noninvasive computed tomography (CT) scans to detect interstitial calcium phosphate deposits (Randall's plaques) and duct of Bellini plugs, which are possible stone precursor lesions. At time of percutaneous nephrolithotomy (PCNL) for stone removal, all accessible individual papillae of 105 patients were endoscopically visualized and video recorded. Image-processing software was used to estimate the percentage of papillary surface occupied by plaque or plug in each pole (upper, middle, lower). The location of stones was also recorded. A radiologist blinded to the mapping results scored presurgical (n = 98) and postsurgical (n = 105) abdominal CT scans for the presence or absence of calcification by pole. The cohort was a mean age of 56 years (range, 23-84 years). Maximum papillary surface area of each area of the kidney occupied by plug correlated with CT calcifications on pre- and postprocedure images by rank sum test. However, maximum plaque surface area did not correlate with radiographic findings (P = .10-.90 for each pole by rank sum test). Sensitivity was 81% and specificity was 69% of CT to detect plugs of at least 1% of the papillary surface area. Calcifications seen on current generation clinical CT scans correspond to ductal plugging involving at least 1% of the papillary surface area. Current clinical CT scan technology appears inadequate for detecting Randall's plaques.

Nutritional status, CT body composition measures and survival in ovarian cancer

ObjectiveBody composition measures (BCMs) are an important predictor of nutritional status in patients with cancer. Poor nutritional status is common in ovarian cancer (OC) and is a well-known variable that influences cancer treatment and outcome. We aim to establish the role of BCMs measured by computed tomography (CT) in predicting outcomes in patients with OC. MethodsWe retrospectively searched our institutional database for patients with stage IIIC/IV OC who underwent surgery as primary treatment at Mayo Clinic between 1996 and 2005 and had adequate presurgical CT images available. For each patient, 1 axial CT image at the level of the 3rd lumbar vertebra was evaluated. Adipose and lean tissues were discriminated using commercially available software. Cox models were fit to evaluate the relationship between patient factors and overall survival (OS). Associations were summarized using hazard ratios (HRs) and corresponding 95% CIs. ResultsA total of 82 patients were identified, with a median age of 68.4years. OS at 1 and 5years was 84.1% and 24.1%, respectively. Older age (P=.01), stage IV disease (P<.001), and subcutaneous and muscular fat<77.21cm2 (P<.001) were independently associated with poor OS. Longer hospital stay was independently predicted by albumin≤3g/dL (P=.03), suboptimal surgery (P=.02), and subcutaneous and muscular fat<77.21cm2 (P<.001). Surgical complications were independently predicted only by albumin≤3g/dL (P<.01). ConclusionsCT BCMs, as indicators of nutritional status, are independent predictors of longer hospital stay and poor OS in patients with OC.

Cochlear implant electrode array misplaced in Hyrtl's fissure

Hyrtl's fissure is a cleft that is present in the developing fetal petrous temporal bone and extends from the area inferior to the round window to the meninges of the posterior fossa. Persistent Hyrtl's fissure, due to incomplete ossification, is considered a rare temporal bone malformation, and is a known cause of perilabyrinthine cerebrospinal fluid fistula. Very few cases are reported as being at risk of complication of cochlear implant surgery. Here we report the case of an 8-year-old boy with misplacement of an electrode array in Hyrtl's fissure. The diagnosis was made postoperatively, since cochlear implant failure was suspected from non-auditory responses. Computed tomography (CT) revealed the extracochlear location of the electrode array. We emphasize the role of presurgical imaging CT and magnetic resonance imaging in detecting temporal bone abnormalities, and we discuss the value of intraoperative auditory nerve response telemetry and postoperative radiological evaluation in diagnosing cochlear implant misplacement.

Pneumatization of the sphenoid sinus in Chinese: the differences from Caucasian and its application in the extended transsphenoidal approach

In recent years, the transsphenoidal approach has been extensively used surgically to treat parasellar, suprasellar, clival, and even petrous lesions. Extended pneumatization of the sphenoid sinus (SS) is considered an indispensable element for the extended transsphenoidal (ETS) approach. Because most anatomical studies of the ETS approach use Caucasian subjects, the present study aims to clarify the pneumatic extension types in Chinese individuals as well as any differences from those in Caucasians and analyze these differences with respect to the application of the ETS approach. A total of 200 computed tomography (CT) images of SSs and 18 adult cadaveric heads were selected for observation and measurement. The conchal, presellar, and sellar types comprised 6, 28.5, and 65.5% of subjects, respectively; according to the extra extension, the prevalence of the lateral, clival, lesser wing, and combined extension sinus types was 11.4, 21.4, 0.8, and 48.1% of subjects, respectively. The percentages of pneumatization of the anterior and posterior clinoid processes, pterygoid process, and optic strut were 5.0, 1.0, 22.3, and 7.0%, respectively. Onodi cells were observed in 61.1% of the sides of the cadaveric heads, including 30.6% with good pneumatization with identifiable optical or ICA bulges. These features were related to poor lateral and clival gasification in Chinese compared with Caucasians, which might make extended surgery more dangerous. However, the anterior pneumatization, especially the higher presentation of Onodi cells, ensures that the anterior ETS approach can be performed safely in Chinese patients. In general, measurements showing smaller sinus volumes and thicker bones with identifiable bone landmarks that are hard to find compared with those in Caucasians suggest increased surgical risks in the Chinese population. In this situation, carefully analysis of presurgical CT and magnetic resonance imaging scans is important. Furthermore, in the ETS approach, the use of stricter intraoperative technological devices such as neuronavigation and ultrasound Doppler is advisable.

Quantitative Measurement of Lung Reexpansion in Malignant Pleural Mesothelioma Patients Undergoing Pleurectomy/Decortication

Malignant pleural mesothelioma (MPM) is a neoplasm that grows circumferentially along the pleura. The tumor and concurrent pleural effusion may reduce lung function by restricting or preventing lung expansion. The purpose of this study was to provide objective evidence that pleurectomy/decortication (P/D) allows trapped lung to reexpand, quantify the reexpansion based on computed tomography (CT) scans, and investigate whether the expansion persists after surgery. A database of 12 patients demonstrating unilateral MPM was collected. Each patient underwent a presurgical CT scan, surgical debulking by P/D, and two postsurgical CT scans (at 1 and 4 months). The lung volume was measured in each scan using an automated algorithm and compared for each patient across time. An increase in the ipsilateral postsurgical lung volume was observed for 10 of 12 patients (83%) 1 month after surgery. The median ipsilateral volume increase was 44% relative to the presurgical ipsilateral volume and 21% relative to the contralateral volume. A statistically significant change in ipsilateral lung volume was not observed between 1‑month and 4‑month postsurgical scans, implying that the volume improvement persisted months after surgery. Debulking of MPM with P/D substantially increased the ipsilateral lung volume relative to both the presurgical ipsilateral volume and the contralateral lung volume. This improvement persisted months after surgery.

Flapless implant surgery in the edentulous jaw based on three fixed intraoral reference points and image‐guided surgical templates: accuracy in human cadavers

In edentulous patients, accurate and stable positioning of a surgical template is impeded by the mobile mucosal tissue. The objective was to evaluate the accuracy of flapless computer-assisted template-guided surgery in an edentulous human cadaver specimen using three fixed oral reference points (FRP) for fixation of the registration mouthpiece and the consecutive surgical template. Oral implants were planned on the computed tomography (CT) of an edentulous human cadaver specimen. Surgical templates have been fabricated using a multipurpose navigation system. Both the registration mouthpiece and consecutive surgical template were supported via three FRP. Study implants were inserted through the guide sleeves and the accuracy was evaluated on a post-surgical CT of the cadaver jaws fused with the pre-surgical planning CT. A Matlab script enabled comparison of the planned surgical path with the study implants. In five maxillary and three mandibular edentulous human cadaver specimens, a total of 51 implants (35 implants in the maxilla and 16 implants in the mandible) have been placed. The mean+/-standard deviation total error (Euclidean distance)/lateral error (normal deviation) were 1.1+/-0.6/0.7+/-0.5 mm at the implant base and 1.2+/-0.7/0.9+/-0.7 mm at the implant tip. The mean angular error was 2.8+/-2.2 degrees. Flapless surgery based on FRP-supported image-guided surgical templates may provide similar accuracy as reported for tooth-supported surgical templates or surgical navigation.