BACKGROUND: The standard imaging technique for the diagnosis of intestinal malrotation remains the upper gastro-intestinal series (UGIS). The lateral view is promoted as important for making a diagnosis. For this, the lateral view should be of adequate quality, and radiologists must know the normal appearance as well as the appearance of duodenal variants, as misdiagnosis may lead to unnecessary surgery.
OBJECTIVE: We aimed to evaluate the quality, findings including the prevalence of the \"descending staircase\" configuration and its correspondence to a diagnosis of duodenum redundum.
METHODS: This was a retrospective study and was conducted in a large tertiary children\'s hospital in the United States. A retrospective review of UGI fluoroscopy exams in children aged ≤ 18 years between January and December 2018 was performed by a pediatric radiologist. First, the lateral view images/cine-loops were assessed independently, followed by the anteroposterior (AP) view. The studies which were designated to have an adequate lateral view were evaluated for configuration of the duodenum and recorded as: normal, abnormal, or normal variant. Also, the presence of a descending staircase configuration was correlated with an AP view for a diagnosis of duodenum redundum.
RESULTS: A total of 26 children (26%) (males:16; females:10) with age range 0 to 16 years had adequate lateral views during UGI exams for inclusion. Of the 26, 18 (69%) were reported as normal, 7 (27%) were reported as having a descending staircase and 1 (4%) was reported as abnormal. The AP view demonstrated 2 abnormal studies (1 malrotation and 1 non-rotation), 6 duodenum redundum and 18 normal exams. The one abnormal lateral duodenum was confirmed as a non-rotation on AP view; the second patient with an abnormal AP view had a normal appearance on the lateral view.
CONCLUSIONS: A total of 26% of UGI studies had adequate lateral views for interpretation. Of these, nearly a quarter (23%) demonstrated the descending stair-case sign corresponding to a diagnosis of duodenum redundum on the AP view. If the lateral view had been used alone, there would have been a missed diagnosis in one patient.

BACKGROUND: Obtaining an accurate tibial lateral view is important during high tibial osteotomy. This study investigated whether the posterior edge of the medial/lateral tibial condyle (PEMTC/PELTC) and the posterior edge of the fibular head (PEFH) in a lateral view could be a reference for determining the accurate tibial lateral view.
METHODS: A total of 75 lower limbs in 38 subjects were evaluated in this study. In order to target healthy knees, subjects undergoing primary total hip arthroplasty were selected. The MF/LF, comprising the anteroposterior distance between PEMTC/PELTC and PEFH, was measured on the lateral view of the tibial bone model based on the tibial anteroposterior (AP) axis (true lateral view: TLV). In addition, measurements were calculated in the model with a 10° external/internal rotation. Using these measurements, linear regression analysis was performed to predict the tibial rotation with MF/LF.
RESULTS: The mean MF/LF was 0.9/4.6 mm (P < 0.001). MF and LF increased with incremental tibial rotation. Regression formulas were derived from these results as follows: Tibial rotation = (1) -1.01 + 1.06 × MF (R2 = 0.87, P < 0.001), (2) -8.70 + 1.86 × LF (R2 = 0.51, P < 0.001). The mean tibial rotation angle when MF was 0 mm was -0.9°.
CONCLUSIONS: Based on formula (1) and actual measurements, the mean tibial rotation angle when MF is 0 mm is an internal rotation of about 1°. Therefore, a lateral view, in which PEMTC and PEFH are seen colinearly, can be the approximate TLV. The MF can be a suitable intraoperative reference in determining TLV.

Introduction The absence of a precise fracture classification system that classifies pertrochanteric fractures into either stable or unstable contributes to a burden on healthcare and has several major implications. We propose an innovative graphical index, which we refer to as posterior protrusion measures (PPM), using plain lateral view radiograph images for the revised AO Foundation (Arbeitsgemeinschaft für Osteosynthesesfragen)/Orthopedic Trauma Association (AO/OTA) classification system. This study aims to: (i) introduce the use of PPM for classifying fractures into stable or unstable under the revised AO/OTA classification system and set the threshold numeric value, (ii) elucidate the reproducibility of inter and intra-observer agreement, and investigate the consistency of fracture classification using PPM versus computed tomography (CT) scan images. Materials and methods Out of 146 patients identified from the database, a total of 126 patients were enrolled in the study. Pertrochanteric fractures were classified as either stable or unstable. Three surgeons were assigned for PPM determination. Regarding the demographical data, the chi-square test was used to assess the significance of each parameter on a categorical scale between the two groups. The independent sample t-test or the Mann-Whitney U test was used to compare the two independent groups. Interclass correlation coefficient (ICC) values for continuous variables and kappa values (κ) for categorical variables were calculated to assess inter-observer and intra-observer agreement. Receiver-operating characteristic (ROC) analysis was used to determine optimal cut-off points of PPM to predict consistency between separate fracture classification groups, one using PPM values with a threshold derived from plain radiograph images, and the other using CT scan images. Results Among a total of 126 pertrochanteric fractures, the A1 (stable) group consisted of 39 patients (10 males, 29 females), whereas the A2 (unstable) group consisted of 87 patients (14 males, 73 females) (not significant, NS). Intraclass correlation coefficient (ICC) values of PPM for the inter-observer agreement were 0.796 (0.723-0.852), 0.664 (0.554-0.751), and 0.702 (0.601-0.781) at first examination and 0.729 (0.635-0.801) at the second. The intra-observer agreement was 0.869 (0.819-0.906) and 0.603 (0.480-0.703). We examined for consistency of fracture classification group of PPM values with a threshold of 0.4 (A1<0.4, A2=0.4 or more) and CT-based group. For the first examination, there was mostly \"moderate\" agreement in fracture classification (stable or unstable) between plain radiograph and CT scan images, κ (95%CI): 0.427 (0.266-0.588), 0.493 (0.335-0.651), and 0.359 (0.176-0.544), and for the second, 0.418 (0.251-0.585), and 0.451 (0.284-0.620), respectively. Conclusion We propose a supplementary tool, namely PPM that allows for possible alternative classification of pertrochanteric fractures into A1 (stable) and A2 (unstable) using plain radiograph images under the revised AO/OTA classification system. In this study, a PPM threshold value of 0.4 demonstrated a moderate inter- and intra-observer agreement. It is noteworthy to mention that there was a satisfactory consistency of fracture classification using PPM derived from plain radiograph images when compared to classification using CT scan images. In addition, the PPM method provides a numerical score.

BACKGROUND: Minimally invasive fluoroscopy-guided screw fixation is an established technique to stabilize fractures of the posterior pelvic ring in orthopaedic surgery. However, safe placement of the screws may be associated with prolonged intervention time and extensive fluoroscopy is a concern. In the current literature, the dose area product (DAP) and fluoroscopy time are often used to describe radiation exposure of the patient. It was the aim of the study to compare DAP to organ doses and the effective dose for four standard views commonly used in pelvic surgery.
METHODS: An anthropomorphic cross-sectional dosimetry phantom, representing the body of a male human (173 cm/73 kg), was equipped with metal-oxide-semiconductor field-effect transistors (MOSFET) in different organ locations to measure radiation exposure. Anteroposterior (APV), lateral (LV), outlet (OLV) and inlet (ILV) of the phantom were obtained with a mobile C-arm, and effective dose and organ doses were calculated. DAP was measured in the built-in ionisation chamber beyond the collimator of the C-arm. The measurements were repeated with a fat layer to simulate an obese patient.
RESULTS: Overall, the highest organ dose was measured in the stomach for ILV (0.918 mSv/min). Effective dose for ILV showed the highest values by far (1.85 mSv/min) and the lowest for LV (0.46 mSv/min). The DAP pattern was completely different to the effective dose with similar values for LV and ILV (12.2 and 12.3 µGy·m2/s). Adding a fat layer had no major effect on the measurements.
CONCLUSIONS: The exposure to radiation varies considerably between different orthopaedic standard views of the pelvis. About the fourfold amount of the effective dose was measured for ILV compared to LV. DAP and irradiation time do not respect either the body region in the field of radiation or the radiosensitivity of the affected organs. Thus, they do not allow a reliable interpretation of the radiation burden the patient is exposed to.

Background: Due to demographic changes, proximal femoral fractures (PFF) in the elderly rise constantly. The standard diagnostic tool is still the X-ray of the pelvis/hip in two planes. Our hypothesis was that the lateral-view X-ray has little influence on classification, planning of the operative procedure, and choice of implant in geriatric patients. Methods: Retrospective analysis of all initial X-rays of PFF in geriatric patients (≥70 years) from May 2018 until August 2019 in a Level I Trauma center. Three experienced consultants categorized the fractures on the ap pelvis view and performed Garden and Pauwels classification as well as a two-staged classification displaced/nondisplaced [for femoral neck fractures (FNF)] or AO Classification [for intertrochanteric fractures (ITF)]. Afterward, they decided the operative strategy as well as implant choice [dynamic hip screw (DHS), intramedullary nail (IMN), or arthroplasty]. After 4 weeks, they categorized all fractures again with now available lateral view X-rays in a different order. Results: Two hundred seven patients (146 female, 61 male; 70.5 vs. 29.5%) with 90 FNF and 117 ITF (43.5 vs. 56.5%) could be included. Age was 84.6 ± 6.9 years. The treatment was in 45 cases DHS, in 82 cases IMN, and for the other 80 cases arthroplasty. The interobserver reliability of the classifications were poor, except for the two-staged classification [Fleiss-κ ap view only = 0.708 (CI 95% 0.604, 0.812) vs. additional lateral = 0.756 (CI 95% 0.644, 0.869)]. Moreover, independent from the classification, there were no significant changes in management and choice of implant with additional lateral view. Conclusions: Regarding our results, we consider the lateral view dispensable for standard X-ray of displaced PFF in geriatric patients. In nondisplaced fractures, it could be added secondary.

UNASSIGNED: The purposes of this study were to develop smile measurements for lateral and oblique view photographs to help in orthodontic analysis and treatment planning, to quantitatively evaluate the relationship between smile esthetics and different types of malocclusion using lateral and oblique view photographs, to identify the cephalometric factors affecting smile measurements.
UNASSIGNED: Patients who came to orthodontic department of a university hospital from 2014 to 2017 and met the inclusion criteria were included and divided into three groups according to Angle\'s classification. Thirteen variables were measured for cephalometric analysis. Twenty-one variables were developed and measured on pretreatment photographs for lateral and oblique smile analysis. ANOVA and Scheffe post hoc test were used to compare cephalometric and smile variables among three groups. Multiple linear regression analysis was performed to identify cephalometric factors affecting smile measurements.
UNASSIGNED: Three-hundred and ninety patients (287 females, 103 males) with mean age of 24.5 ± 7.6 years reached the criteria. All cephalometric variables differed significantly among three groups. Except for maxillary teeth exposure number, visible maxillary width, and lip thickness ratio, all smile variables differed significantly. Smile characteristics had significant correlation with some cephalometric measurements.
UNASSIGNED: Smile patterns on the lateral and oblique view photographs can be affected by different types of malocclusion. Therefore, we suggest to include lateral and oblique smile view photographs in the data collection for orthodontic treatment planning.

In a computer-aided diagnosis (CAD) system, especially for chest radiograph or chest X-ray (CXR) screening, CXR image view information is required. Automatically separating CXR image view, frontal and lateral can ease subsequent CXR screening process, since the techniques may not equally work for both views. We present a novel technique to classify frontal and lateral CXR images, where we introduce angular relational signature through force histogram to extract features and apply three different state-of-the-art classifiers: multi-layer perceptron, random forest, and support vector machine to make a decision. We validated our fully automatic technique on a set of 8100 images hosted by the U.S. National Library of Medicine (NLM), National Institutes of Health (NIH), and achieved an accuracy close to 100%. Our method outperforms the state-of-the-art methods in terms of processing time (less than or close to 2 s for the whole test data) while the accuracies can be compared, and therefore, it justifies its practicality. Graphical Abstract Interpreting chest X-ray (CXR) through the angular relational signature.

With CT (computed tomography) chest gaining more importance as a diagnostic tool, chest X-ray especially the lateral view is taken less commonly nowadays. Besides CT chest is also proven to be superior to chest X-ray in patients with major blunt trauma. We are presenting a 68-year old male who was partially treated from outside for a left sided pneumonia. He came to our hospital because of persisting chest pain. Chest X-ray, frontal view (postero-anterior) was almost normal except for a mild opacity in the left lower zone. CT scan of the chest revealed a fluid collection posteriorly enclosed within enhancing pleura. Chest X-ray, left lateral view showed a corresponding posterior pleural based opacity. We are presenting this case to highlight the importance of the lateral view of the chest X-ray. In selected cases there is still a role for the lateral view. With the three dimensional visualization provided by the CT, the lateral view of the chest may be easier to understand. Consequent to the initial diagnosis by CT further follow up can be done with the chest X-ray. In a limited way this mitigates unnecessary expenditure and more importantly prevents the patient from exposure to harmful radiation in the form of repeated CT.

BACKGROUND: To evaluate the effectiveness of the Robert view in assessing trapeziometacarpal arthrosis and to compare the accuracy of the Robert and lateral views in staging trapeziometacarpal (TM) joint arthrosis.
METHODS: Patient demographics were obtained. Four participating raters reviewed 62 randomly selected thumb x-rays of patients presenting with thumb TM joint pain. Lateral and Robert-hyperpronation views were assessed using an analysis of 13 criteria.
RESULTS: X-rays of 62 thumbs for 58 patients were evaluated. The average patients\' age was 64 (47-87) and 51 (80%) were females. The majority of X-rays evaluated fell into stage 3. Stage 2 was the second most common level of arthritis encountered and the least was stage 1. More osteophytes were encountered in the trapezium than metacarpal on both the Robert and lateral views. The Robert view was superior in detecting osteophytes on the trapezium than the lateral view. Osteophyte size varied from 1.7 to 2 mm. The lateral view displayed 61 cases with dorsal metacarpal subluxation (98%). The Robert view displayed 48 cases (77%) with radial metacarpal subluxation and 9 cases (15%) with ulnar metacarpal subluxation. Thumb metacarpal adduction deformity was encountered on the lateral view in 20 cases (32%) whereas on the Robert view it was encountered in 14 cases (23%). Subchondral sclerosis was encountered on the Robert view in 56 thumbs (90%) while it was seen on the lateral view in 52 thumbs (84%). Pantrapezial arthritis involving the STT joint was encountered equally in 16 cases (26%) on the Robert view and the lateral views. The study found a moderate level of interrater reliability on both the lateral and Robert views. With the exception of osteophytes encountered on the trapezium versus the metacarpal, there were no other statistically significant findings.
CONCLUSIONS: This study confirms that each of the Robert and lateral views offer unique information and combining both views enhances the ability to assess radiographic disease severity, and should be the recommended set of X-rays for assessing TM osteoarthrosis.

Slipped upper femoral epiphysis (SUFE) is one of the known causes of cam-type femoroacetabular impingement (FAI). The aim of this study was to determine the proportion of FAI cases considered to be secondary to SUFE-like deformities. We performed a case-control study on 96 hips (75 patients: mean age 38 years (15.4 to 63.5)) that had been surgically treated for FAI between July 2005 and May 2011. Three independent observers measured the lateral view head-neck index (LVHNI) to detect any SUFE-like deformity on lateral hip radiographs taken in 45° flexion, 45° abduction and 30° external rotation. A control group of 108 healthy hips in 54 patients was included for comparison (mean age 36.5 years (24.3 to 53.9). The impingement group had a mean LVHNI of 7.6% (16.7% to -2%) versus 3.2% in the control group (10.8% to -3%) (p < 0.001). A total of 42 hips (43.7%) had an index value > 9% in the impingement group versus only six hips (5.5%) in the control group (p < 0.001). The impingement group had a mean α angle of 73.9° (96.2° to 53.4°) versus 48.2° (65° to 37°) in the control group (p < 0.001). Our results suggest that SUFE is one of the primary aetiological factors for cam-type FAI.