Inferior Extent Research Articles

A rare case of disseminated tuberculosis presenting as multiple visceral abscesses: retropharyngeal abscess, epidural abscess, pulmonary Koch’s, hepatic granuloma and splenic abscess

Extrapulmonary TB can present with plethora of clinical signs and symptoms, the spectrum of which remains boundless. Retropharyngeal abscess, epidural abscess, splenic abscess, hepatic granuloma are rare presentations of extrapulmonary TB which requires paramount clinical expertise for diagnosis and timely management thereby preventing dangerous complications. Here is a case report of a 6 year old boy presenting with 2 months history of fever, neck pain and swelling, difficulty in swallowing solid food, restricted neck movements, weight loss and family history of TB contact. Examination revealed bilateral jugulodigastric (level I and II) cervical lymphadenopathy (around 2×2 cm), neck rigidity and a paramedian bulge over posterior pharyngeal wall (measuring 3×3 cm), the inferior extent of which was difficult to visualize on oral cavity examination. Patient was worked up keeping in mind the high possibility of TB, radiography and ultrasonography of neck confirmed the presence of retropharyngeal abscess. CECT neck, chest and abdomen was done to find the extent of lesion and to look any other evidence of tuberculosis which revealed presence of retropharyngeal abscess, epidural abscess, pulmonary Koch’s, hepatic granuloma and splenic abscess with features s/o tuberculosis. He was started on ATT on clinico-radiological basis, his abscess was drained and cheesy material and pus were sent for microbiological and histo-pathological examination, although microbiological evidence was non-contributory, histopathology confirmed tuberculous retropharyngeal abscess. This case reporting was done to elicit the rare presentation of EPTB and the need of high degree of clinical suspicion for early diagnosis and timely treatment to prevent future complications.

Tracheobronchopathia osteochondroplastica: a case report highlighting the importance of clinico-radiologic correlation

Tracheobronchopathia osteochondroplastica (TBPO) is a rare and benign idiopathic disease of the tracheobronchial tree, characterized by osseous, and/or cartilaginous submucosal nodules involving the anterior and lateral walls of the airways with sparing of the posterior wall. We present a case of a 51-year-old non-smoker female, presenting with a 2-year history of gradually enlarging anterior neck mass with foreign body sensation, frequent throat clearing, and occasional hoarseness. She was initially diagnosed with recurrent respiratory papillomatosis due to the presence of nodules on flexible laryngoscopy. A plain neck and chest CT then showed irregularity of the tracheal walls with calcified nodules projecting into the lumen, sparing the posterior wall, consistent with TBPO. Fiberoptic bronchoscopy with biopsy was also done which confirmed the inferior extent of the nodules down to the level of the carina, and the presence of fragments of mature bone tissue within the nodules.

Comparison of a Pre-Trained AI Contouring Model to Unseen Institutional Data

To compare contours generated by a pre-trained, commercial AI model to those manually drawn in house. Previously treated radiotherapy patients (N = 20 per site) for several sites (brain, head & neck, thorax, abdomen, pelvis) with approved structure sets were selected for this retrospective analysis. For the planning CT of each patient, a pre-trained AI model auto-contoured several OARS: bladder, brain, eyes, femurs, kidneys, lenses, mandible, and parotids, etc. A two-step rejection method filtered the results based on unmatched structure names (i.e., contours existing in only one of the two structure sets causing incorrect auto-matching of structure names by the comparison algorithm), and structures with different superior and/or inferior extents. From the remaining contours, DSC (Dice Similarity Coefficient) and HD95% (95th percentile of Hausdorff Distance) were calculated between auto and manually generated contours using vendor-supplied software; median values were then calculated. The entire data set contained 592 structures at the on-set of analysis. After applying the rejection filters, the remaining data had 294 structures; a large portion of filtering was due to unmatched names. Out of these, OARs with contours from at least 10 patients (N>9) were further analyzed to include the 25th and 75th percentile for DSC and HD95%. Results from this analysis (structures with N>9) are presented in the table below, where results of left-right paired structures are combined into one row. The submandibular glands, larynx, and optical nerves (5 < N < 10) all had median DSC < 0.77 while lungs had median DSC > 0.98 (N = 6). Parotids and lenses had poor DSC and HD95% scores and may require significant contour editing to achieve agreement with our clinical conventions. This study highlights the difficulty with retrospective analysis of contours with an external trained model due to variations in the superior/inferior extent of tubular structures such as rectum, cord, esophagus, etc. CONCLUSION: Results are encouraging, given that the pre-trained commercial model has not seen our institutional data. The pre-trained AI contouring model matched very well to manual contours for large volume, higher contrast structures but did not match well for parotids and lenses. Variability in conventions regarding the superior/inferior extent of some structures hinders retrospective comparison with a pre-trained AI model.

Native Glenoid Depth and Hill-Sachs Lesion Morphology in Traumatic Anterior Shoulder Instability

Background: Although Hill-Sachs lesions (HSLs) are assumed to be influenced by glenoid characteristics in the context of bipolar bone loss, little is known about how glenoid concavity influences HSL morphology. Purpose: To investigate the relationship between the native glenoid depth and HSL morphological characteristics. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Computed tomography images of bilateral shoulders from 151 consecutive patients with traumatic unilateral anterior shoulder instability were retrospectively reviewed. Patients were categorized into flat (<1 mm), moderate (1-2 mm), and deep (>2 mm) groups based on the native glenoid depth measured from the contralateral unaffected shoulder. The HSL morphological characteristics included size (depth, width, length, and volume), location (medial, superior, and inferior extent), and orientation (rim and center angle). The glenoid characteristics included diameter, depth, version, and bone loss. The patient, glenoid, and HSL morphological characteristics were compared among the 3 depth groups. Subsequently, the independent predictors of some critical HSL morphological characteristics were determined using multivariate stepwise regression. Results: After exclusion of 55 patients, a total of 96 patients were enrolled and classified into the flat group (n = 31), moderate group (n = 35), and deep group (n = 30). Compared with those in the flat group, patients in the deep group were more likely to have dislocation (38.7% vs 93.3%; P = .009) at the primary instability and had a significantly larger number of dislocations (1.1 ± 1.0 vs 2.2 ± 1.8; P = .010); moreover, patients in the deep group had significantly deeper, wider, larger volume, more medialized HSLs and higher incidences of off-track HSLs (all P≤ .025). No significant differences were detected among the 3 groups in HSL length, vertical position, and orientation (all P≥ .064). After adjustment for various radiological and patient factors in the multivariate regression model, native glenoid depth remained the strongest independent predictor for HSL depth (β = 0.346; P < .001), width (β = 0.262; P = .009), volume (β = 0.331; P = .001), and medialization (β = −0.297; P = .003). Conclusion: The current study sheds light on the association between native glenoid depth and the morphology of HSLs in traumatic anterior shoulder instability. Native glenoid depth was independently and positively associated with HSL depth, width, volume, and medialization. Patients with deeper native glenoids were more likely to have off-track HSLs and thus require more attention in the process of diagnosis and treatment.

Magnetic resonance imaging grading of pituitary macroadenoma – SIPAP classification revisited

BackgroundMagnetic resonance imaging (MRI) is regarded as the modality of choice in diagnosis of pituitary macroadenomas. Since surgery is the first line therapy for all pituitary adenomas, simple and reproducible MRI classification based on major directions of tumour growth is an essential tool. SIPAP MRI classification for pituitary adenoma describes tumor extension in parasellar, suprasellar, infrasellar, anterior and posterior directions. We, therefore, evaluated reproducibility of SIPAP classification in reporting of pituitary adenomas. MethodsForty-nine patients with biopsy-proven pituitary macroadenoma were graded according to SIPAP classification. Data was analyzed using Stata version 15. Interobserver variability was calculated using Cohen’s Kappa. Comparison between grading before and after treatment was performed by Chi-square test. P values < 0.05 were considered statistically significant. ResultsIndividual tumour extensions according to SIPAP for pre- and post-operative grading showed significant difference (p-value <0.001), except for anterior extension. For suprasellar extension, 67.3 % patients had pre-operative grade-3 and 63.3 % had post-operative grade-0. For infrasellar extension, 51.0 % had pre-operative grade-2 and 71.4 % had post-operative grade-0. Anterior, posterior and parasellar extensions showed increased frequency in grade-0 in post-operative stage compared to pre-operative. Substantial inter-observer agreement was achieved for Superior, Inferior, Anterior and Posterior extent with all Kappa statistics values above 0.7 (p-value <0.001). ConclusionWe propose incorporating simple and objective SIPAP classification in routine MR reporting for ideal pituitary tumour delineation, relationship to juxtasellar structures and tumour size, hence facilitating greater success rate in surgical and subsequent clinical management.

Posteroinferior relevant scapular neck offset in reverse shoulder arthroplasty: key player for motion and friction-type impingement in a computer model.

Range of motion (ROM) and prevention of notching remain a challenge for reverse shoulder arthroplasty (RSA). Both may be affected by the morphology of the scapula. The purpose of this study was to define anteroinferior (a) and posteroinferior (p) relevant scapular neck offset (RSNO) and to examine the hypothesis that pRSNO is significantly smaller than aRSNO, and influences rigid body motion (RBM). Adapting glenosphere implantation strategies may therefore be of value. In this computer model study, we used deidentified computed tomographic scans of 22 patients (11 male and 11 female; mean age: 72.9 years) with massive cuff tears without joint space narrowing. Eight RSA glenoid configurations were tested with a constant neck-shaft angle (145°). Two baseplate types (25 mm; 25 + 3 mm lateralized) and 4 glenospheres (GS) (36 mm; 36 +2 mm of eccentricity; 39 mm; 39 + 3 mm) were used. RSNO was defined as the standardized measurement of the horizontal distance from the inferior extent of the GS to the bony margin of the scapula after baseplate positioning (flush to inferior glenoid extent; neutral position: 0° inclination and 0° version-both software computed). There was a highly significant difference between pRSNO and aRSNO for both genders (P<.001). pRSNO was always smaller than aRSNO. pRSNO was strongly correlated with external rotation (ERO: 0.84) and extension (EXT: 0.74) and moderately correlated with global ROM (GROM: 0.68). There was a moderately strong correlation between aRSNO and internal rotation (IRO: 0.69). pRSNO was strongly correlated with aRSNO, EXT, ERO, IRO, adduction (ADD) and GROM (0.82, 0.72, 0,8, 0.71, 0.82, 0.76) in female patients and with EXT and ERO (0.82, 0.89) in male patients. The median pRSNO allowing for at least 45° ERO and 40° EXT was 14.2 mm for men and 13.8 mm for women. For all patients and models, pRSNO ≥14 mm increased EXT, ERO, and GROM significantly compared with pRSNO <14 mm (P<.001). The combination of lateralization and inferior overhang (eccentricity) led to the most significant increase of pRSNO for each GS size (P<.001). This is one of the first RSA modeling studies evaluating nonarthritic glenoids of both genders. The lateral scapular extent to glenoid relationship is asymmetric. pRSNO is always smaller than aRSNO for both genders and was a critical variable for EXT and ERO, demonstrating additional strong correlation with aRSNO, IRO, ADD, and GROM in female patients. pRSNO ≥14 mm was a safe value to prevent friction-type impingement. Combining increased glenosphere size, lateralization, and inferior overhang gives the best results in this computer-simulated setting.

Scarless Neck Feminization: Chondrolaryngoplasty Through Endoscopic Transoral Vestibular Approach.

We present in this paper a novel approach to perform endoscopic chondrolaryngoplasty without any external visible scars. The technique involves utilizing the endoscopic transoral vestibular approach. We have modified the technique by using the placement of a suture immediately above the anterior commissure, which provides a marker for the inferior extent of cartilage resection. Laryngoscope, 133:1099-1102, 2023.

Poster 162: Glenoid Bone Loss Directly Affects Hill-Sachs Morphology: An Advanced 3-Dimensional Analysis

Objectives:The purpose of this study was to 1.) qualitatively and quantitatively analyze the interplay between glenoid bone loss (GBL) and Hill-Sachs lesions (HSL) in a cohort of anterior instability patients using 3-dimensional (3-D) imaging software and 2.) assess the relationships between GBL and HSL characteristics.Methods:Patients with anterior shoulder instability with a minimum of 5% GBL with evidence of HSL confirmed on computed tomography were identified. 3-D models of the unilateral proximal humeral head and en face sagittal oblique view of the glenoid were reconstructed using Mimics (Materialise NV, Leuven, Belgium) software. GBL as well as surface area (SA), width, defect length, and glenoid track width was quantified. The volume, SA, width, and depth of identified HSLs were quantified along with their location (medial, superior, and inferior extent) on the humeral head. The severity of glenoid bone loss was categorized by low grade (0-10%), moderate grade (>10% to 20%), high grade (>20% to 30%), and extensive (>30%). Analysis of variance was then computed to determine significance (p < 0.05) between severity of GBL and associated HSL parameters.Results:100 patients met inclusion criteria (mean age: 27.9 years, range: 18 to 43 years), which included 58 right shoulders and 42 left shoulders (84 male, 16 female). Among groups, 32 patients presented with low grade GBL (μ GBL = 6.1%), 38 patients with moderate grade (μ GBL = 16.2%), 17 with high grade ( μ GBL = 23.7%), and 13 with extensive GBL (μ GBL = 34.0%), with an overall mean GBL of 18.1% (range 5% - 39%). Patients with 0-10% GBL had significantly narrower (average and max width) ( p < 0.03) and deeper (average depth) (p = 0.002) HSLs compared with all other GBL groups, while greater GBL was associated with wider and shallower HSLs. GBL width, percent width loss, defect length, and glenoid track width all significantly differed across the four GBL groups (p < 0.05).Conclusions:Hill-Sachs Lesions (HSLs) have different morphological characteristics depending on the amount of glenoid bone loss (GBL). GBL is directly related to the characteristics of HSLs. Smaller glenoid defect size is associated with narrower and deeper HSLs. Management of the humeral head and glenoid must be appropriately tailored given the distinct interplay between GBL severity and HSL.

Glenoid Bone Loss Directly Affects Hill-Sachs Morphology: An Advanced 3-Dimensional Analysis

Background: While the glenoid track concept presents a useful prediction for recurrent glenohumeral instability, little is known about the humeral head bony architecture as it relates to glenoid erosion in the setting of bipolar bone loss. Purpose: To (1) qualitatively and quantitatively analyze the interplay between glenoid bone loss (GBL) and Hill-Sachs lesions (HSLs) in a cohort of patients with anterior instability using 3-dimensional imaging software and (2) assess the relationships between GBL and HSL characteristics. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Patients were identified who had anterior shoulder instability with a minimum 5% GBL and evidence of HSL confirmed on computed tomography. Unilateral 3-dimensional models of the ipsilateral proximal humeral head and en face sagittal oblique view of the glenoid were reconstructed using MIMICS software (Materialise NV). GBL surface area, width, defect length, and glenoid track width were quantified. The volume, surface area, width, and depth of identified HSLs were quantified with their location (medial, superior, and inferior extent) on the humeral head. Severity of GBL was defined as percentage glenoid bone surface area loss and categorized as low grade (5%-10%), moderate grade (>10% to 20%), high grade (>20% to 30%), and extensive (>30%). Analysis of variance was then computed to determine significance (P < .05) between severity of GBL and associated HSL parameters. Results: In total, 100 patients met inclusion criteria (mean age, 27.9 years; range, 18-43 years), which included 58 right shoulders and 42 left shoulders (84 male, 16 female). Among groups, there were 32 patients with low-grade GBL (mean GBL = 6.1%), 38 with moderate grade (mean GBL = 16.2%), 17 with high grade (mean GBL = 23.7%), and 13 with extensive (mean GBL = 34.0%), with an overall mean GBL of 18.1% (range, 5%-39%). Patients with 5%-10% GBL had significantly narrower HSLs (average and maximum width; P < .03) and deeper HSLs (average depth; P = .002) as compared with all other GBL groups, while greater GBL was associated with wider and shallower HSLs. GBL width, percentage width loss, defect length, and glenoid track width all significantly differed across the 4 GBL groups (P < .05). Conclusion: HSLs had significantly different morphological characteristics depending on the severity of GBL, indicating that GBL was directly related to the characteristics of HSLs. Patients presenting with smaller glenoid defects had significantly narrower and deeper HSLs with less humeral head surface area loss, while greater GBL was associated with wider and shallower HSLs.

Location of inferior mesentery artery ligation in rectal cancer surgery: how to make decisions based on available evidence

There are still controversies as to the location of ligating the inferior mesenteric artery and the central lymph node dissection during rectal cancer surgery. The reason is that the level of evidence in this area is low. Existing studies are mostly retrospective, analyses or small-sample randomized controlled trials. These results showed no significant differences between high-ligation and low-ligation, in terms of anastomotic leakage and other short-term postoperative complications. Low-ligation seems better for the recovery of postoperative genitourinary function. Due to the low rate of central lymph node metastasis and many other confounding factors that affect the survival rate, it is difficult to conclude the survival benefits of ligation site or central node dissection. It is necessary to carry out some targeted, well-designed, large-scale randomized controlled trials to explain the related issues of inferior mesenteric artery ligation site and extent of central lymphadenectomy.

1322 Two Staged Skin Pedicle Reconstruction of Superior Helical Rim

Abstract Introduction Skin grafting onto the ear has its challenges, loss of the skin results in inadequate vascular bed for the graft leading to decreased uptake 1,2. As a result, advancement flaps or sacrifice of the underlying cartilage allows primary closure with compromised aesthetics. A two staged procedure however leads to acceptable scarring, can be performed under local anaesthetic, is quick and easy enabling transfer of skin to acutely exposed cartilage. The authors demonstrate a two staged reconstruction technique of the superior helix after traumatic degloving of the dermal tissues. Method Under local anaesthetic an incision in line with the most inferior extent of the skin loss is made. A subdermal plane is expanded superiorly, and the exposed auricular cartilage inserted, healing of the adjacent margins occurs and enables later skin transfer. The patient was discharged on oral antibiotics and returns at two weeks to have the pedicle divided in an outpatient setting. A further skin incision superior to the extent of the tip of the helix is performed. This skin flap is then thinned and folded to reconstruct the posterior aspect of the ear. The skin is sutured in place and the patient is sent home on oral antibiotics. A further reviewed in two weeks to check healing is advised and the patient was subsequently discharged. Conclusions In conclusion, this is demonstrated to be a useful technique to add to the Oral and Maxillofacial Surgeons armament for reconstruction of the superior helix when iatrogenic or traumatic loss of skin coverage occurs.

A Novel and Accurate Palpation Method for Identification of the L4 Spinous Process: A Preliminary Study of Accuracy

ObjectiveThe purpose of this study was to assess a novel method of lumbar spinous process (SP) palpation by using magnetic resonance imaging (MRI) high-signal marker reference standards for verification. MethodsClinicians (doctors of chiropractic) in this study used either: (1) the standard/traditional method of identifying the L4 SP using the supracristal plane (n = 14) or (2) a novel method that manually induced sacral motion to identify the L5 and then the L4 SP (n = 54). The clinicians, blinded to the results of each other, used a grease pencil to mark the location identified as the L4 SP. An MRI high-signal marker then was taped across this location. The MRI scans were assessed by a radiologist, blinded to the palpation method, who extended a line posteriorly from the superior and inferior extent of the L4 SP and determined whether the high-signal marker was within the lines bordering the L4 SP (ie, “on-target”). ResultsPalpation using the traditional method showed a 35.7% accuracy, with 5 of 14 “on target” and all “off target” being too superior. Palpation using the novel method showed 77.8% accuracy, with 42 of 54 “on target” and 3 “off target” being too superior and 9 “off target” too inferior. ConclusionsThe novel method performed better than the traditional method. The novel method shows promise. Additional prospective research should be conducted to fully assess the accuracy of the novel method compared with traditional methods of palpation.

Advanced 3-Dimensional Characterization of Hill-Sachs Lesions in 100 Anterior Shoulder Instability Patients

We sought to qualitatively and quantitatively describe characteristics of Hill-Sachs lesions (HSL) in a cohort of anterior shoulder instability patients using advanced 3-dimensional (3-D) modeling software and assess the impact of various HSL parameters on the HSL volume, location, and orientation in patients with anterior shoulder instability. A total of 100 recurrent anterior instability patients with evidence of HSL with a mean age of 27.2 years (range= 18 to 43 years) were evaluated. Three-dimensional models of unilateral proximal humeri were reconstructed from CT scans, and the volume, surface area (SA), width, and depth of identified HSLs were quantified along with their location (medial, superior, and inferior extent). Multiple angular orientation measures of HSLs were recorded, including Hill-Sachs rim (HSLr) angle in order to classify the level and location of potential humeral head engagement. Mann-Whitney U test assessed the relationship between measured parameters. By volume, larger HSL had greater humeral head surface area (HH SA) loss (P= .001), HSL width (P= .001), were more medial (P= .015), and more inferior (P= .001). Additionally, more medial lesions had greater HSLr angles (P= 0.001). The mean depth, width, and volume of HSLs were 3.3 mm (range= 1.2-7.1 mm), 16.0 mm (range= 6.2-30.4 mm) and 449.2 mm3 (range= 62.0-1365.6 mm3), respectively. The medial border of the HSL extended to 17.2 ± 4.4 (range= 9.3-28.3 mm) off the most medial edge of the HH cartilage margin (medialization). The mean HSLr was 29.3 ± 10.5°. There was a statistically significant association between HSL medialization and HSL volume, position, and orientation. More medialized HSL have larger volume, greater width, more SA loss and higher lesion angles and are more inferior in the humeral head. As it has been established that more medialized lesions have poorer clinical outcomes, this study highlights that HS lesions have varying angles and medialization, which may portend eventual treatment and outcomes. IV, case series.

Defining the dose-volume criteria for laryngeal sparing in locally advanced oropharyngeal cancer utilizing split-field IMRT, whole-field IMRT and VMAT.

PurposeTo determine the optimal dose‐volume constraint for laryngeal sparing using three commonly employed intensity modulated radiation therapy (IMRT) approaches in patients with oropharyngeal cancer treated to the bilateral neck.Materials and methodsThirty patients with stage II‐IVA oropharynx cancers received definitive radiotherapy with split‐field IMRT (SF‐IMRT) to the bilateral neck between 2008 and 2013. Each case was re‐planned using whole‐field IMRT (WF‐IMRT) and volumetric modulated arc therapy (VMAT) and plan quality metrics and dose to laryngeal structures was evaluated. Two larynx volumes were defined and compared on the current study: the Radiation Therapy Oncology Group (RTOG) larynx as defined per the RTOG 1016 protocol and the MDACC larynx defined as the components of the larynx bounded by the superior and inferior extent of the thyroid cartilage.ResultsTarget coverage, conformity, and heterogeneity indices were similar in all techniques. The RTOG larynx mean dose was lower with WF‐IMRT than SF‐IMRT (22.1 vs 25.8 Gy; P < 0.01). The MDACC larynx mean dose was 17.5 Gy ± 5.4 Gy with no differences between the 3 techniques. WF‐IMRT and VMAT plans were associated with lower mean doses to the supraglottic larynx (42.1 vs 41.2 vs 54.8 Gy; P < 0.01) and esophagus (18.1 vs 18.2 vs 36 Gy; P < 0.01).ConclusionsModern whole field techniques can provide effective laryngeal sparing in patients receiving radiotherapy to the bilateral neck for advanced oropharyngeal cancers.SummaryWe evaluated laryngeal dose in patients with locally advanced oropharyngeal cancer treated to the bilateral neck using split‐field IMRT (SF‐IMRT), whole‐field IMRT (WF‐IMRT) and volumetric arc therapy (VMAT). All three techniques provided good sparing of laryngeal structures and were able to achieve a mean larynx dose < 33 Gy. There were no significant differences in dose to target structures or non‐laryngeal organs at risk among techniques.

A New Orthotic Device for Maintaining Neck Flexion Following Tracheal and Cricotracheal Resection.

View Video S1 Laryngoscope, 131:1805–1809, 2021

Evaluation of a commercial deformable image registration algorithm for dual-energy CT processing.

PurposeSeveral dual‐energy computed tomography (DECT) techniques require a deformable image registration to correct for motion between the acquisition of low and high energy data. However, current DECT software does not provide tools to assess registration accuracy or allow the user to export deformed images, presenting a unique challenge for image registration quality assurance (QA). This work presents a methodology to evaluate the accuracy of DECT deformable registration and to quantify the impact of registration errors on end‐product images.MethodsThe deformable algorithm implemented in Siemen Healthineers's Syngo was evaluated using a deformable abdomen phantom and a rigid phantom to mimic sliding motion in the thorax. Both phantoms were imaged using sequential 80 and 140 kVp scans with motion applied between the two scans. Since Syngo does not allow the export of the deformed images, this study focused on quantifying the accuracy of various end‐product, dual‐energy images resulting from processing of deformed images.ResultsThe Syngo algorithm performed well for the abdomen phantom with a mean registration error of 0.4 mm for landmark analysis, Dice similarity coefficients (DSCs) > 0.90 for five organs contoured, and mean iodine concentrations within 0.2 mg/mL of values measured on static images. For rigid sliding motion, the algorithm performed poorer and resulted in noticeable registration errors toward the superior and inferior scan extents and DSCs as low as 0.41 for iodine rods imaged in the phantom. Additionally, local iodine concentration errors in areas of misregistration exceeded 3 mg/mL.ConclusionsThis work represents the first methodology for DECT image registration QA using commercial software. Our data support the clinical use of the Syngo algorithm for abdominal sites with limited motion (i.e., pancreas and liver). However, dual‐energy images generated with this algorithm should be used with caution for quantitative measurements in areas with sliding motion.

The Value of Multiparametric MRI for Assessment of Inferior Vena Cava Wall Invasion by Renal Cell Carcinoma Thrombus: A Prospective Feasibility Study

Background: Renal cell carcinoma (RCC) thrombus invasion in the inferior vena cava (IVC) wall needs adequate resection to improve survival. Surgical planning to avoid positive vascular surgical margins and recurrent disease can be facilitated by imaging capable of diagnosing this invasion and the extent of the thrombus. Objective: To evaluate the diagnostic performance of multiparametric MR imaging (mpMRI) for detecting inferior vena cava (IVC) wall invasion and extent of renal cell carcinoma (RCC) thrombus. Methods: In this prospective study, twenty consecutive patients underwent mpMRI before open radical nephrectomy with IVC thrombectomy was performed in a single high-volume institution by one urologist (PM) blinded for mpMRI findings. Primary endpoint was mpMRI negative- and positive predictive value (NPV/PPV) for IVC wall invasion as encountered during surgery. IVC wall invasion was assessed on mpMRI by a radiologist prior to the surgery based on qualitative imaging parameters. Also, NPV and PPV were calculated with incremental use of quantitative parameters. Therefore, the association between IVC wall invasion and the maximum IVC and renal vein orifice diameter, and the cranial extent of the thrombus was evaluated by logistic regression. After ROC analysis an optimal cut-off point was selected for significantly associated quantitative parameters. NPV and PPV were calculated using this optimal cut-off point. Results: mpMRI NPV and PPV for IVC wall invasion based on qualitative parameters was 82% and 100%, respectively. An increase in IVC diameter was significantly associated with IVC wall invasion (p &lt; 0.05). With incremental use of an IVC diameter cut-off value of 27 mm NPV and PPV for IVC wall invasion were 100% and 89%, respectively. Conclusion: mpMRI is able to reliably diagnose IVC wall invasion of RCC thrombus and can optimize radical surgical resection.

Evaluation of surgical risk and prognosis between thyroid nodules of size

The objective of this study was to evaluate the surgical risk and prognosis between thyroid nodules of size <1 and ≥1 cm and to explore whether it is reasonable generally to ignore the diagnosis and treatment of thyroid nodules and thyroid carcinoma <1 cm in wide areas of China. A retrospective observational study included all first-time thyroid surgery patients between January 2005 and December 2016 of the First Affiliated Hospital of Harbin Medical University. All patients were divided into two groups (group A: <1 cm, group B: ≥1 cm) according to the maximum diameter of the nodules and demographics, surgery procedure, pathology, postoperative complications, morbidity, and mortality were analyzed. A total of 6,317 patients were reviewed and 3,424 (54.20%) of them were malignant; 2,128 patients in group A and 4,189 in group B. Patients in group A had better pathological diagnosis, inferior extent of lymph node metastasis, less surgical complexity, fewer postoperative complications, and longer disease-free survival (DFS). Thyroid operations were safer and involved fewer postoperative complications when thyroid nodules were <1 cm and patients who were diagnosed with malignant thyroid disease had superior prognoses. Underdeveloped regions of China should diagnose and treat thyroid nodules <1 cm early.

A novel and accurate palpation method for identification of the L4 spinous process

BackgroundEffective physical examination of patients with back pain is essential for several clinical specialties, including rheumatology, orthopedics, neurology, anesthesiology, physical medicine, chiropractic, and physical therapy. Accurate identification of lumbar spinous process (SPs) as landmarks is fundamental to such examination; however, identifying lumbar SPs through manual palpation has been shown to be surprisingly inaccurate. During a clinical trial using precisely placed accelerometers to assess zygapophyseal joint cavitation, a novel method of palpation was used to improve palpation accuracy.MethodsThis case series was approved by the institutional IRB. Palpation to identify the L4 SP (primary landmark for the study) was performed by clinicians with a minimum of 5 years of practice experience, using either: 1) the standard/traditional method of identifying the L4 SP using the supracristal plane (n=14); or 2) a novel method that began by identifying the superior aspect of the sacrum through manually inducing sacral motion and then identifying the L5 SP and then the L4 SP (n=54). The clinicians worked independently on separate subjects and had no access to the results of one another during the palpation phase of the project. The clinicians applying either palpation method used a grease pencil to mark the location they identified as the L4 SP. An MRI high‐signal marker was then taped across this location. A mid‐sagittal scout MRI scan was then taken with the subject in the supine position. The de‐identified scans were assessed by a radiologist, blinded to the palpation method, who marked the superior and inferior extent of the L4 SP on the MRI scans and drew a line extending posteriorly through the skin and perpendicular to the lateral edge of the film (i.e., perpendicular to the MRI gantry table). The radiologist then determined if the high signal marker visible on the image was within the lines bordering the L4 SP (i.e., accurately identifying the SP, reported here as “on target”), on one of the lines (also considered to be “on target”), or too far superior or too far inferior. If too far superior or inferior, the radiologist assessed the extent of the discrepancy.ResultsPalpation by the traditional method showed a 35.7% accuracy, 5 of 14 on target [2 (40%) on a line]; and 9 of 14 off target, all off target being too superior (4 at the L3 SP, 5 at the L2‐L3 interspace). Palpation by the novel method showed 77.8% accuracy; 42 of 54 on target [9 (21%) on a line], and 12 of 54 off target, 3 off target being too superior (all at the L3 SP) and 9 too inferior (7 at the L5 SP, 2 at the L5‐S1 interspace).ConclusionsThe novel method performed better than the traditional method in this case series. We conclude that the novel method shows promise, and propose that additional prospective research be conducted to fully assess the accuracy of the novel method compared with traditional methods of palpation.Support or Funding InformationNIH/NCCIH Grant# – 3R01AT000123‐06S2This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Pretrial outlining quality assurance in PIVITOLBoost.

50 Background: PIVOTALBoost is a Phase III randomised controlled trial (CRUK/16/018) of radiotherapy to prostate and pelvic nodes versus prostate alone with or without prostate boost. To minimise impact of target volume delineation (TVD) variation on trial outcome, pre-trial radiotherapy quality assurance (RTQA) was implemented to identify and correct potential variations. Methods: Participating centres offering a prostate boost submitted two pre-accrual outlining benchmark cases: one with a central zone boost (GTVpb) only and another with GTVpb (peripheral zone), CTVp/psv and CTVn. A detailed outlining protocol and diagnostic information were provided to centres. Submitted outlines were compared to consensus volumes created by the trial management group (TMG). The TMG deemed the volumes acceptable or as having acceptable or unacceptable variation. Detailed feedback was provided for each submission. Unacceptable variations required resubmission. Results: 32 investigators submitted pre-trial outlines. GTVpb was the most incorrectly outlined volume; 22 (69%) outliners had unacceptable errors for case 2 GTVpb, 17 (53%) for case 1 GTVpb. Most common GTVpb error was inferior extent of lesion followed by incorrect lesion outlined. 12 (38%) of outliners had unacceptable errors for CTVp/psv, most commonly due to delineation at the prostate apex. 8 (25%) outliners had unacceptable CTVn mostly due to incorrect vessel delineation. Of 26 (81%) outliners required to resubmit at least 1 case, 3(12%) required a second resubmission due to unacceptable errors on first resubmission. Conclusions: The majority of pre-trial outlining submissions had unacceptable errors requiring resubmission of at least one case. This was predominantly due to boost delineation error which is a relatively new skill for prostate clinical oncologists in the UK. This suggests robust on-trial RTQA is imperative to minimise further variation. Clinical trial information: ISRCTN80146950.