Coronal Computed Tomography Images Research Articles

A purpose-design computational method for estimation of plane of maximum curvature in Adolescent Idiopathic Scoliosis.

Adolescent idiopathic scoliosis (AIS) is a complex three-dimensional (3D) deformity, and the plane of maximum curvature (PMC) is proposed to reflect these clinical features, which refers to a vertical plane presenting the maximum projected spinal curvature and its parameters include the PMC Cobb and orientation (angle between PMC and sagittal planes). This study aimed to develop a computational method (CM) for PMC estimation. Twenty-nine patients with AIS and computed tomography (CT) images were recruited. For CT, PMC was determined by rotating a vertical plane about its vertical axis with 5°increment until the maximum Cobb angle was measured. For CM, PMC was estimated via identifying the eight points (the corner points of the superior and inferior endplates of the upper and lower end-vertebrae respectively) in the coronal and lateral CT images. Two experienced raters repeated the PMC estimation three times with one-week interval. The intra-class correlation coefficient (ICC) and Bland-Altman method were used for statistical analysis. Twenty-seven right thoracic curves (RTs) (mean Cobb: 46.1°±12.4°) and 23 left thoracolumbar/lumbar (LTLs/LLs) (mean Cobb: 30.6°±11.1°) were analysed. The intra- and inter-rater ICC values were >0.91 and 0.84 in RTs and LTLs/LLs, respectively. The PMCs obtained from the CM and CT were showed good agreement was also observed between the PMCs obtained from the two methods according to ICC (>0.90) and Bland-Altman method assessments. This purpose-design computational method could provide reliable and valid estimation of PMCs for AIS, which has potential to be used as an alternative for 3D assessment.

Benign cystic mesothelioma of the liver: A rare hepatic cyst

A 66-year-old woman presented to our hospital with upper abdominal pain and right chest tightness for 2 weeks. She had past history of hypertension under medical control for decades. Surgical history included laparoscopic cholecystectomy for cholelithiasis, as well as subtotal hysterectomy for leiomyoma and adenomyosis more than 10 years ago. In the clinic, one soft and mobile mass at left upper quadrant was palpated. Intravenous contrast-enhanced coronal computed tomography image of abdomen showed a 15 cm low-attenuation, nonenhancing cystic mass at left upper quadrant of the abdomen, and a small septum with some calcifications (arrow) was also noted.

Deep learning model for automated kidney stone detection using coronal CT images

Kidney stones are a common complaint worldwide, causing many people to admit to emergency rooms with severe pain. Various imaging techniques are used for the diagnosis of kidney stone disease. Specialists are needed for the interpretation and full diagnosis of these images. Computer-aided diagnosis systems are the practical approaches that can be used as auxiliary tools to assist the clinicians in their diagnosis. In this study, an automated detection of kidney stone (having stone/not) using coronal computed tomography (CT) images is proposed with deep learning (DL) technique which has recently made significant progress in the field of artificial intelligence. A total of 1799 images were used by taking different cross-sectional CT images for each person. Our developed automated model showed an accuracy of 96.82% using CT images in detecting the kidney stones. We have observed that our model is able to detect accurately the kidney stones of even small size. Our developed DL model yielded superior results with a larger dataset of 433 subjects and is ready for clinical application. This study shows that recently popular DL methods can be employed to address other challenging problems in urology.

The importance of Böhler's angle in calcaneus geometry: A finite element model study.

Objectives Calcaneal fractures are the most common tarsal fractures following a foot-ankle trauma. The Böhler’s angle is an important measurable angle before, during, and after surgery. In this study, we aimed to investigate correlation between Böhler’s angle, calcaneal strength, and subtalar joint stress using a finite element analysis (FEA).Patients and methods Between January 2016 and December 2016, computed tomography (CT) scans were used with MIMICS® software for FEA. The ankle and foot of a 23-year-old male person with a height of 180 cm and weighing 80 kg was modeled as reference. Raw coronal CT images were obtained in Digital Imaging and Communications in Medicine format with the resolution of 512X512 pixels and 0.3-mm slice intervals in 135 kV. The structures including tibia, fibula and 26 other bones (talus, calcaneus, cuboid, navicular, three cuneiforms, five metatarsals, and 14 components of phalanges), cartilage and ligamentous tissues were modeled to form ankle joint. After determining Böhler’s angle as 35 degrees for the reference model, a fracture line was created on calcaneus. Calcaneus was remodeled with the Böhler’s angle of 45, 40, 30, 25, 20, 10, and 0 degrees respectively. All models were transferred to ANSYS software for FEA and the loads on the lower extremities with normal posture were applied on models.Results Analysis of all models based in the reference model revealed that maximum tension values on calcaneus increased, while the Böhler’s angle decreased, indicating a statistically significant difference. The decreased Böhler’s angle indicated statistically significantly higher maximum tension values (p=0.04). Action force in subtalar joint was evaluated by comparing with the forces in reference model. The increased Böhler’s angle was found to be associated with statistically significantly decreased amount of load on subtalar joint. The decreased Böhler’s angle was related to the statistically significantly increased amount of load on subtalar joint.Conclusion Our study results suggest that decreased Böhler’s angle increases the possibility of subtalar arthrosis, although overcorrection of the Böhler’s angle seems not to increase the risk of subtalar arthrosis.

Extraocular muscle diameter in Makurdi, North Central Nigeria: what is normal?

Background: Establishing normal values of extra ocular muscle (EOM) diameter is essential in a given population. Factors including race, region, gender and environment affect the normal diameter of the EOM. The aim of the study was to determine the normal sizes of the EOM in a population in the North Central part of Nigeria using computed tomography (CT).Methods: One hundred and eighty-three CT images of patients who underwent craniofacial imaging for other conditions and who met the inclusion criteria were evaluated. The maximum diameters of the EOMs on coronal reformatted CT images which are the superior group (SG) (superior rectus and the levator palpebral), inferior rectus (IR) medial rectus (MR) and lateral rectus (LR) were assessed.Results: The mean values±SD obtained were 3.65±1.13, 3.93±0.94, 3.40±0.67, 3.43±0.92 for SG, 1R, MR, and LR muscles respectively on the right and 3.61±1.07, 3.86±0.92, 3.34±0.70, 3.42±0.08 for SG, IR MR and LR muscles respectively on the left. The order IR>SR>MR>LR of average muscle diameter was obtained. The females in this region showed slightly higher mean values of the diameter of the EOM than the males; however, this was not statistically significant. By age, there was no consistent correlation.Conclusions: The established normal values of the EOM may serve as a reference point for ophthalmologist and for cosmetic surgeons and also will add to the pool of the existing knowledge for academic purposes.

Histopathological and Radiographic Features of Osteolysis After Fixation of Osteochondral Fragments Using Poly-L-Lactic Acid Pins for Osteochondral Lesions of the Talus

Background: Fixation of osteochondral fragments is a potential option for treating an osteochondral lesion of the talus (OLT) involving large lesions in the remaining articular cartilage surface. Bioabsorbable devices, especially those made of poly-L-lactic acid (PLLA), can be used for the fixation of an OLT. Postoperative osteolysis surrounding the PLLA pins is occasionally observed; however, the significance of osteolysis remains unknown. Purpose: To elucidate the association between osteolysis surrounding the PLLA pins, histopathological findings in subchondral bone, and preoperative Hounsfield unit (HU) values at the pin fixation site. Study Design: Case Series; Level of evidence, 4. Methods: This retrospective analysis included 20 patients with OLT (11 men and 9 women; mean age, 20.9 years; 1 bilateral case). Tissue from the osteochondral fragment was collected intraoperatively using a bone biopsy needle for histological evaluation. The fragment was fixed through the biopsy hole using a PLLA pin. Osteolysis surrounding the PLLA pin was assessed at 1 year postoperatively using magnetic resonance imaging (MRI). Histopathological scores were assigned based on trabecular bone loss, empty lacunae, inflammatory granulation tissue, cartilage-like tissue, and the presence of osteoclasts. The HU values around the pin insertion site, detected on the postoperative MRI scans, were measured using the region of interest based on the preoperative coronal and sagittal computed tomography (CT) images. Results: Osteolysis was observed postoperatively in 9 ankles (42.9%). Histopathological evaluation revealed that the osteolysis group had a significantly higher pathological score than the nonosteolysis group (10.2 vs 6.3; P < .001). Lower HU values were identified in the osteolysis group on preoperative coronal and sagittal CT images (P < .05). The histopathological score negatively correlated with preoperative HU values (Pearson r = −0.46; P = .037). Conclusion: Intraoperative biopsy of the OLT allowed for histopathological evaluation of the same site as that of the PLLA pin fixation. Our findings suggest that preoperative subchondral trabecular deterioration is associated with the incidence of postoperative osteolysis surrounding the PLLA pin. Additionally, low preoperative HU values in subchondral bone under OLT may serve as a predictor of osteolysis surrounding the PLLA pin.

Quantitative Analysis of Deltoid Ligament Degradation in Patients With Chronic Ankle Instability Using Computed Tomographic Images.

Rotational ankle instability (RAI) is associated with the faster onset of severe ankle osteoarthritis via dysfunction of the anterior talofibular ligament, calcaneofibular ligament, and deltoid ligament. No specific clinical examination is available for RAI, and diagnostic imaging has limitations in evaluating ligament degradation. This study investigated the deltoid ligament degeneration using Hounsfield unit (HU) values on computed tomography (CT) images. Patients were enrolled in this retrospective analysis if they had undergone magnetic resonance imaging (MRI) and CT scans of the ankle. The chronic ankle instability (CAI) group comprised 20 ankles with CAI (9 men, 11 women; mean age, 28.7 years) and the control group comprised 28 ankles (16 men, 12 women, mean age, 41.3 years). The average HU values of the deep posterior tibiotalar ligament (dPTL) that constitutes the deltoid ligament were measured on coronal CT images, and MRI results were used as a reference. All patients were subdivided based on the MRI findings of dPTL injury such as fascicular disruption, irregularity, and the loss of striation. A strong negative correlation was identified between age and HU values for all patients (Spearman ρ = -0.63; P < .001). The mean HU values of the dPTL for participants aged <60 years were 81.0 HU for the control group (21 ankles) and 69.5 HU for the CAI group (P = .0075). No significant differences in the HU values were observed for the dPTL among the MRI subgroups. In addition to the conventional imaging examination such as stress radiographs and MRI, HU measurements of CT images could be useful for quantitatively and noninvasively evaluating degenerative changes in the deltoid ligament for CAI patients to assist the diagnosis of RAI. Level III. case-control study.

Postoperative morphological changes over time of vascularized scapular bone used for mandibular reconstruction: A retrospective cohort study

Currently, sequential morphological changes of vascularized scapular bone for mandibular reconstruction have remained unreported. We retrospectively analyzed 18 patients with defects on the lateral segment of the mandible who underwent postoperative computed tomography (CT) scanning at 1, 6, 12, and 24 months postoperatively. Using the cross-sectional coronal CT images during each assessment, we measured the height and thickness of the grafted scapular bone at points 10 and 30 mm away from the mesial segment and evaluated their differences over time. Then, the relationship between the morphological changes of the grafted scapular bone and the distance from the mesial bone segment, the number of occlusal supports on the contralateral side of the mandible, and the correlation of sex and age were evaluated. The height of the grafted scapular bone decreased by approximately 11% and its thickness increased by 14% within 24 months postoperatively. The bone thickness increase was greater at point 30 mm from the mesial bone segment. Patients with two occlusal contacts (premolar and molar) on the contralateral side had a significantly higher rate of bone thickness increase. Furthermore, the graft morphology was not associated with age or sex. A vascularized scapular bone thickens over time, which depends on the distance from the mesial bone segment and the occlusal contact regions on the contralateral side of the mandible.

Widening of sternoclavicular joint distances in blunt chest trauma

Purpose: Blunt chest trauma has high mortality and morbidity rates. The aim of this study was to evaluate the relationship between trauma findings and sternoclavicular joint (SCJ) distances in patients with blunt chest trauma. &#x0D; Materials and Methods: Between May 2019- September 2019, Thorax Computed Tomography (CT) images of 102 patients (78 males, 24 females, aged 19-88 years) with blunt chest trauma were evaluated retrospectively. Rib fractures, costal cartilage fractures and other signs of trauma were evaluated. SCJ distances were measured at the inferior, mid, and superior segments in the coronal reformatted CT images. Post-traumatic SCJ expansion was evaluated in patients with rib and costal cartilage fractures. Additionally, SCJ and the presence of other post-traumatic signs were compared. An inter-observer reliability analysis with Intraclass correlation coefficient (ICC) scores with 95% CIs were calculated. &#x0D; Results: In the presence of fractures of 1st to 4th ribs a statistically significant widening of superior and mid segments of the ipsilateral SCJs were detected. A 2-mm or greater difference of widening of the superior segment of the ipsilateral SCJ compared to the contralateral joint was found statistically significant for hemothorax, pneumothorax, and wall emphysema. The inter-observer agreement was excellent for the measurements of the SCJ on coronal plane, having an ICC score ranging from 0.921 to 0.961 (95% CI). &#x0D; Conclusion: The expansion of the ipsilateral SCJ distances in rib fractures in the upper part of the chest wall shows that SCJ performs an important role in the absorption of energy to the chest wall.

S2868 A Serendipitous Identification of Contained Duodenal Perforation

INTRODUCTION: Peptic ulcer disease (PUD) is a condition defined by defects in the gastric and/or duodenal mucosa that extend through the muscularis mucosa. Sequalae of untreated PUD include gastrointestinal (GI) bleeding, gastric outlet obstruction and perforation. Typical presenting symptoms of upper GI perforation include sudden onset of severe sharp abdominal pain, peritoneal signs and severe sepsis or septic shock. CASE DESCRIPTION/METHODS: We present a case of a 71-year-old woman with chronic back pain on celecoxib who presented with mild progressively worsening abdominal pain, non-bilious/non-bloody vomiting and decreased oral intake. Abdomen was benign and initial laboratory tests were unrevealing. Computed tomography (CT) revealed a 6.6 cm heterogeneous complex cystic/solid mass originating from the second portion of duodenum with large exophytic component, and abutting the pancreatic head, liver, proximal duodenum, portal vein and inferior vena cava (Figure 1). Esophagogastroduodenoscopy (EGD) revealed a fistulous tract along the duodenal sweep leading into an extra-luminal cavity (Figure 2) and multiple Forrest Class III duodenal bulb ulcers. Intraprocedural surgical consultation was obtained and a decision was made to proceed with endoscopic ultrasonography (EUS). EUS revealed a 40.2 × 27.3 mm hypoechoic heterogeneous porta-hepatis lesion with ill-defined borders, containing a well-circumscribed anechoic component consistent with contained perforation cavity. Fine needle biopsy (FNB) was performed with pathology revealing a grade 1 well-differentiated duodenal neuroendocrine tumor (D-NET) with immunohistochemical stains positive for synaptophysin, negative for chromogranin A and less than 1% positivity for Ki67 (Figure 3). Of note, serum chromogranin A level was markedly elevated to 1,105 ng/mL (normal: < 93 ng/mL). A pancreaticoduodenectomy was advised, however, patient declined. DISCUSSION: Although most common cause of duodenal perforations is PUD secondary to Helicobacter pylori infection and non-steroidal anti-inflammatory drugs (NSAIDs) use, other etiologies include diverticulum, regional infections, autoimmune conditions, ischemia, Bouveret syndrome, chemotherapy and localized tumors. NETs account for 0.5% of all cancers and D-NETs comprise 5-8% of all GI-NET. Although contained GI perforations have atypical presentations, one should always keep tumor on the differential. To our knowledge, this is the first case report of D-NET leading to perforation.Figure 1.: Intravenous and oral contrast enhanced axial (A) and coronal (B) CT images of the abdomen demonstrating a complex heterogeneous and cystic mass in the porta hepatis region. The mass is interposed between and inseparable from the duodenum (straight white arrow) and head of the pancreas (curved white arrow). The inferior aspect of the mass is heterogeneous (white arrowhead) with areas of hyper-intensity compatible with tumor enhancement. The superior aspect of the mass is cystic with complex fluid attenuation (black arrowhead) consistent with the histopathologic findings of perforation and hematoma.Figure 2Figure 3

Quantitative Analysis of the Deltoid Ligament Degradation in Chronic Ankle Instability Patients using the CT Value

Category:Ankle; OtherIntroduction/Purpose:Chronic lateral ankle instability (CLAI) that is developed after multiple lateral ankle ligament injury lead to ankle osteoarthritis. Although isolated deltoid ligament injury is rare compared to lateral ankle ligament injury, deltoid ligament tear, especially deep posterior tibiotalar ligament (PTT) can be observed arthroscopically in CLAI patients. Unphysiological loading of the ankle joint with CLAI might cause degradation of the deltoid ligament. This study aimed to investigate image findings of the deltoid ligament using computed tomography (CT) value for quantitative analysis of degenerative ligament changes in CLAI patients.Methods:Among the enrolled patients who underwent ankle magnetic resonance imaging (MRI) and CT scans of the ankle, this retrospective analysis included 24 ankles without ankle osteoarthritis, osteochondral lesion of the talus (OLT), flatfoot and ankle fractures (14 males and 10 females; mean age, 42.8 years) as a control group, and 14 CLAI ankles without OLT (7 males and 7 females; mean age, 31.1 years) as CLAI group. The CT scans were performed using a 64-slice multidetector row CT. Deep PTT was detected on coronal T2-weighted MR images. Both the coronal MR and CT images were matched for analysis, then average CT values were measured using the region of interest that was applied to the detected area of deep PTT on the CT images.Spearman’s correlation coefficient was used to evaluate the correlation between age and CT value in the control group.Results:The strong negative correlation was identified between age and CT value in the control group (Spearman ρ= -0.88; p< 0.001). The CT value of the deep PTT are degraded with aging. Mean CT value of deep PTT in participants under 60 years old were 79.9 HU (95% CI, 75.1-84.8) in the control group (18 ankles), and 66.5 HU (95% CI, 58.6-74.5) in the CLAI group (14 ankles) (Welch’s t test; p = 0.005).Conclusion:MRI techniques and protocols recently have been developed, however, some limitations remain such as a quantitative evaluation of the ligament. Our findings suggest that the CLAI can lead to degradation of the deltoid ligament via an overloading of medial ankle structures. Additionally, CT values should be useful for quantitatively evaluating ligament status including degenerative changes.

Estimation of plane of maximum curvature for the patients with adolescent idiopathic scoliosis via a purpose-design computational method.

The coronal Cobb angle is commonly used for assessing the adolescent idiopathic scoliosis (AIS); however, it may underestimate the severity of AIS while the plane of maximum curvature (PMC) could be a promising descriptor for three-dimensional assessment of AIS. This study aimed to develop a computational method (CM) for estimating the PMC based on the coronal and sagittal images of the spine, and to verify the results with computed tomography (CT). Twenty-eight thoracic and 24 lumbar curves from 30 subjects with AIS were analysed. For the CM, PMC was estimated via identifying the two corner points at the superior endplate of upper-end vertebra and the inferior endplate of lower-end vertebra in the coronal and sagittal CT images separately (eight corner points in total). For the CT, PMC was determined through rotating the spine images axially until the maximum Cobb angle was found. Intraclass correlation coefficient (ICC), Bland-Altman method and linear regression analysis were used for the statistical analyses. The high ICC values (intra- > 0.91; inter- > 0.84) suggested very good intra- and inter-rater reliability of the CM in PMC estimation. The high ICC values (> 0.91) and assessment of Bland-Altman method demonstrated a good agreement between thePMC acquired using the CM and CT. The generated linear regression equations (R2 > 0.69) could allow to estimate the PMC (originally measured through the CT) via the CM. The developed computational method could estimate reliable and valid PMC for the patients with AIS, and become feasible for three-dimensional assessment of AIS. III.

Para-acetabular Radiopaque Densities in Patients With Femoroacetabular Impingement: A Retrospective Assessment of Prevalence and Characteristics.

Background:Femoroacetabular impingement (FAI) syndrome is a common source of hip pain associated with chondrolabral injury. There is a subset of patients with FAI syndrome who present with radiopaque densities (RODs) adjacent to the acetabular rim.Purpose:To evaluate the prevalence, characteristics, and patient-specific factors associated with RODs adjacent to the acetabulum in patients treated with hip arthroscopy for symptomatic FAI.Study Design:Case series; Level of evidence, 4.Methods:Between November 2014 and March 2018, a total of 296 patients who underwent hip arthroscopy for FAI with a labral tear were reviewed retrospectively. Patient-specific variables were collected, including age, sex, lateral center-edge angle (LCEA), and alpha angle. Imaging (computed tomography) and surgical reports were reviewed for the location and characteristics of RODs, as well as subsequent labral treatment technique. Patients were excluded if they were treated for extra-articular hip pathology, had a revision procedure, or had a diagnosis other than FAI with a labral tear. No patient was excluded for any history of systemic inflammatory disease. Binary logistic regression was used to compare age, LCEA, and alpha angle for patients with or without radiopaque fragments. An alpha level of 0.05 was used to indicate statistical significance.Results:A total of 204 patients met inclusion criteria; 33 patients (16.2%; 16 males, 17 females) had para-acetabular RODs. There were no statistically significant differences in age (P = .82), sex (P = .92), LCEA (P = .24), or alpha angle (P = .10) among patients with or without an ROD. Of the 33 patients, 29 (87.9%) had fragments in the anterosuperior quadrant. Overall, 31 patients (93.9%) were treated with labral repair in addition to correction of the underlying bony impingement, while 2 patients (6.1%) underwent focal labral debridement owing to poor labral tissue quality around the RODs. Twenty-five patients (76%) had identifiable RODs, which were excised at the time of surgery. The mean (± SD) ROD size measured on axial and coronal computed tomography imaging was 6.3 ± 5.5 mm and 4 ± 4.5 mm, respectively.Conclusion:Age, sex, LCEA, and alpha angle were not predictive of the presence of para-acetabular RODs. Approximately one-sixth of all patients with FAI had RODs identified on computed tomography, which were typically located at the anterosuperior acetabulum. The majority of hips with para-acetabular RODs were amenable to labral repair. The relative prevalence and lack of predictive patient-specific indicators for these fragments suggest that a high degree of suspicion is necessary when evaluating patients with FAI.

Computed Tomographic Findings of Nasal and Paranasal Sinuses in Patients Scheduled for Rhinoplasty in Shahid Mostafa Khomeini Hospital during 2011-13

Objective: Rhinoplasty is done to improve the morphology of the nose whilst also restoring its physiological function. Currently it is possible to perform rhinoplasty and endoscopic sinus surgery simultaneously. The need has therefore arisen to evaluate anatomical variation within the nose and paranasal sinuses in symptom-free patients who are scheduled for rhinoplasty. Coronal computed tomography (CT) is the standard method used to evaluate the nose and paranasal sinuses. We aimed to evaluate the frequency of anatomical variation noted within the nose and paranasal sinuses on coronal CT in patients scheduled for rhinoplasty. Methods: This is a descriptive, cross-sectional, retrospective study of CT findings in 84 patients who underwent rhinoplasty at Mostafa Khomeini Hospital, Shahed University, Tehran between 2011-13. The CT findings were evaluated in three different predefined categories: nasal septal, nasal turbinate, and paranasal sinuses abnormalities. Results: The study involved 84 individuals, consisting of 26 men and 58 women. The most frequent findings in the nasal septum category were nasal septal deviation (69.04%) and nasal septal spur (33.33%), whereas concha bullosa (45.23%) and inferior turbinate hypertrophy were the most frequent abnormality in the nasal turbinates category. Mucosal thickening of the sinuses (45.23%) and partial opacification of the sinuses (21.42%) were the most common findings in the paranasal sinuses. Conclusion: The high frequency of anatomical variation, inflammatory and congenital abnormal findings in CT images of the paranasal sinuses in patients scheduled for rhinoplasty indicates that preoperative CT examination may be useful in avoiding multiple surgical operations and in reducing costs.

Soft Tissue Damage in Patients With Hemifacial Microsomia.

The aim of this study was to evaluate the extent of the damage to soft tissues on the affected side in patients with hemifacial microsomia (HFM). Nine patients with HFM were included in this study and underwent computed tomography (CT) examination in the craniofacial area. The axial and coronal CT images were used for evaluating the damage to related soft tissues. The results showed that the masseter muscle, temporal muscle, pterygoid muscles, and parotid gland were damaged on the affected side in all 9 patients with HFM. However, the extent of the damage to the pterygoid muscles was less than that to the masseter muscle, temporal muscle, and parotid gland. These findings indirectly support the crucial role of hemorrhage in the development of HFM, and the extent of damage to soft tissues may depend on the distance and barrier effect of the mandible between the hemorrhage and the affected tissues.

Anatomical variations of sphenoid sinus among patients undergoing computed tomography of paranasal sinus

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; The approach to sphenoid sinus still remains a clinical challenge, despite the arrival of endoscopy, computed tomography (CT) and functional endoscopic sinus surgery (FESS). The complex and variable anatomy of the sphenoid sinus can be difficult to appreciate with standard axial or coronal CT images of the sinus. The study was done with the objective to study the anatomy of the sphenoid sinus and its variations, and to compare the prevalence of variants obtained in our study with the reported cases in the literature.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; The CT scans of 168 normal slides obtained from 84 patients with paranasal sinus were analysed using triplanar imaging provided by 64-slice spiral CT. The prevalence of each of the sphenoid sinus variation was also analysed. &lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results:&lt;/strong&gt; Results showed that the prevalence of pneumatization of the anterior clinoid process, greater wing of the sphenoid, and the pterygoid process was 17.85%, 22.61% and 32.14%, respectively. Protrusion of the internal carotid artery, optic nerve, maxillary nerve, and the vidian nerve was 47.61%, 36.90%, 25% and 26.19%, respectively. Dehiscence of internal carotid artery, optic nerve, maxillary nerve, and the vidian nerve was 30.95%, 29.76%, 14.28% and 22.61%, respectively. The prevalence of pneumatization in the Onodi cells was seen in 17.85% of the cases. Association of septa with an internal carotid artery was seen in 29.7% of the cases. Septa attachment to the optic nerve was also observed in 27.3% of the cases.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; The triplanar imaging (section thickness of 1 mm) is a better three-dimensional image of the sphenoid sinus, compared to coronal imaging. Triplanar imaging guides the surgical approach of the sphenoid sinus with mentally reconstructed three-dimensional images.&lt;/p&gt;&lt;p class="abstract"&gt; &lt;/p&gt;

Deep learning segmentation of kidneys with renal cell carcinoma.

e16098 Background: Renal cell carcinoma (RCC) is the most common kidney malignancy and the eighth most common cancer overall, with more than 60,000 new cases and nearly 15,000 deaths in the United States each year. The majority of RCC is asymptomatic and detected incidentally on computed tomography (CT) scans performed for other indications. Multiple prior studies have highlighted the potential for a lesion to be missed or mischaracterized. Artificial intelligence (AI), the mimicking of human cognition by computers, has promise for improving radiological accuracy. Convolutional neural networks (CNNs), a type of AI, apply a feed-forward design to an artificial neural network. Multi-layered CNNs thus have application in biomedical imaging and radiology. In this study we describe an approach for automatic localization and segmentation of the kidneys on contrast enhanced CT scan. Methods: This IRB approved retrospective study included patients who were diagnosed with RCC and had an abdominal CT scan with IV contrast from 2011 to 2019. For each abdominal CT scan, the kidneys and any renal lesions were manually segmented by a board-certified abdominal radiologist on the coronal post-contrast phase of the CT scan. Two CNNs were developed and trained to segment the kidneys automatically. Initially, the CNN implemented a regression algorithm that predicted a 3D bounding box around each kidney. Subsequently, the second CNN used a 3D/3D U-Net algorithm that received the bounding cube as its input and outlined the kidney as an output. After training, the CNN algorithms were assessed by a Sørensen-Dice coefficient. Results: The first CNN that predicted a 3D bounding box around each kidney was trained on 127 abdominal CT exams. The second CNN that segmented the kidneys with RCC was trained on 259 bounding boxes that encompassed the kidneys. The Sørensen–Dice coefficient for segmentation of the kidneys with RCC was 0.92. Conclusions: These results demonstrate that two CNNs can be used in succession to segment the kidneys with RCC on a coronal CT image with high accuracy. Moreover, as the subjects included patients with RCC, medical renal disease, and cystic renal disease, the outcome further supports the role of CNN in evaluation of complex cases rather than pristine training sets. Future work will focus on segmentation of RCC lesions.

Visualisation of the vomerovaginal canal during endonasal transpterygoid approaches and CT imaging diagnosis.

The vomerovaginal canal (VVC) and palatovaginal canal (PVC) are two canals that open forward to the posterior wall of the pterygopalatine fossa (PPF). Although the anatomy and computed tomography (CT) appearances of the PVC have been well studied, the VVC has been rarely reported, especially in endoscopic examinations. Some studies have even failed to distinguish the PVC from the VVC on CT images. The purpose of this study was to demonstrate the anatomy of the VVC on endoscopy and reveal its differences from the PVC, and to analyse the relative positions of the VVC, PVC, and pterygoid canal on CT images. Ten dry skull bases were studied to observe the structures involved in the formation of the VVC. Dissection of four cadaveric heads was performed to demonstrate the anatomy of the VVC on endoscopy. Coronal CT image analysis in 70 patients was conducted to evaluate the distances and relative positions between the VVC, PVC, and pterygoid canal. The PVC and VVC were also compared on axial CT images. The osteological study showed the top wall of the VVC was the antero-inferior wall of the sphenoid sinus. The VVC may be a helpful landmark in endoscopic endonasal transpterygoid approaches. Steps and discrimination in the dissections of the VVC and PVC were described. The interval between the PVC and VVC could be observed on both coronal and axial CT images. The coronal CT images of patients showed differences in the positions and distances among the three canals at both the anterior and posterior apertures of the PVC. The VVC can be easily mistaken for the PVC if its existence is not suspected. The anatomical morphologies and trajectories of the VVC and PVC differed on both nasal endoscopy and CT. The existence of the VVC should be considered during surgery and CT diagnosis within this area.

Effect of natural full weight-bearing during standing on the rotation of the first metatarsal bone.

To evaluate the rotational change in the first metatarsal bone (1MT) of the foot during natural standing using an upright computed tomography (CT) scanner with 320-detector rows. A total of 52 feet of 28 asymptomatic subjects (aged 23-39 years) were evaluated in the natural standing position with or without weight-bearing. A foot pressure plate was used to determine the non-weight-bearing (NWB) or single leg full-weight-bearing (s-FWB) conditions. CT examinations were performed using a noise index of 15 for a slice thickness of 5 mm, rotation speed of 0.5 sec, and slice thickness of 0.5 mm. The rotation of the 1MT was measured on the coronal CT image, which cut the sesamoids' bellies in the frontal slide of the first metatarsal and sesamoids perpendicular to the longitudinal bisection of the third metatarsal, and compared between the weight-bearing conditions. Intra- and inter-observer reliabilities of the rotation angle were also evaluated. The intra- and inter-observer correlation coefficients were 0.961 and 0.934, respectively. The 1MT pronation angle was significantly greater in the s-FWB condition than in the NWB condition (15.2° ± 5.4° vs. 12.5° ± 5.3°, P < 0.01). No sex difference was found in the magnitude of the 1MT pronation angle as a result of weight-bearing. This study first demonstrated that pronation of 1MT occurs due to natural full-weight-bearing in asymptomatic feet. The 1MT's rotational movement under weight-bearing conditions may relate to the onset and pathogenesis of the hallux valgus. Clin. Anat. 32:715-721, 2019. © 2019 Wiley Periodicals, Inc.

Kidney cortex segmentation in 2D CT with U-Nets ensemble aggregation.

This work presents our contribution to one of the data challenges organized by the French Radiology Society during the Journées Francophones de Radiologie. This challenge consisted in segmenting the kidney cortex from coronal computed tomography (CT) images, cropped around the cortex. We chose to train an ensemble of fully-convolutional networks and to aggregate their prediction at test time to perform the segmentation. An image database was made available in 3 batches. A first training batch of 250 images with segmentation masks was provided by the challenge organizers one month before the conference. An additional training batch of 247 pairs was shared when the conference began. Participants were ranked using a Dice score. The segmentation results of our algorithm match the renal cortex with a good precision. Our strategy yielded a Dice score of 0.867, ranking us first in the data challenge. The proposed solution provides robust and accurate automatic segmentations of the renal cortex in CT images although the precision of the provided reference segmentations seemed to set a low upper bound on the numerical performance. However, this process should be applied in 3D to quantify the renal cortex volume, which would require a marked labelling effort to train the networks.