Head Neck Research Articles

Use of jugular venous pressure to optimize outcomes of vestibular schwannoma resection: a review of the literature and proof of concept

Background: Surgical resection of vestibular schwannoma (VS) and other benign posterior fossa tumors is often curative if gross total resection is achieved, however, these lesions pose unique challenges due to their intricate location and proximity to critical structures. Approaches for resection often utilize lateral head rotation and neck flexion in order to optimize the surgical field. However, this may inadvertently occlude cerebral venous drainage, elevating intracranial pressure (ICP) and increasing intraoperative bleeding, potentially increasing the operative risk to patients. Methods: We review relevant literature regarding the effects of head rotation and neck flexion on internal jugular vein (IJV) occlusion and ICP, and highlight the notion that head rotation and flexion may occlude the ipsilateral IJV, increasing ICP. Subsequently, we propose a novel technique using continuous, real-time monitoring of jugular bulb pressure (JBP) to detect obstructions in jugular venous flow and guide optimal head positioning prior to VS resection. Results: As proof of concept, we present a single-patient case in which JBP monitoring was employed to optimize head positioning prior to a VS resection, which shows a significant reduction in JBP compared to traditional positioning. Conclusion: This innovative approach offers promise in enhancing the safety and efficacy of intracranial surgery for VS and other neurosurgical procedures.

Correlation of Ultrasound Guided (USG) Fine Needle Aspiration Cytology (FNAC) With Postoperative Histopathology in the Diagnosis of Thyroid Swelling

Background: Thyroid swelling is a common problem in Bangladesh. Early and systematic evaluation of a nodular thyroid swelling is necessary as it is a frequent presentation of thyroid neoplasia. USG Guided Fine needle aspiration cytology (FNAC) is one of the diagnostic tools for early evaluation of thyroid nodules. USG Guided FNAC is considered as a cost-effective, simple, minimally invasive and easily repeatable procedure for preoperative screening in the diagnosis for most of the thyroid lesions. The objective of this study is to determine the sensitivity and specificity of USG Guided fine needle aspiration cytology (FNAC) and compare the efficacy with histopathology in diagnosis of thyroid swellings. Objective: To evaluate the sensitivity and specificity of USG Guided fine needle aspiration cytology (FNAC) and histopathology for the diagnosis of thyroid swelling. Method: This Observational Prospective Study was performed in the department of Otolaryngology & Head Neck Surgery, Dhaka Medical College Hospital. Dhaka over 6 month’s duration from January 2019-June 2019. Total 50 patients with thyroid swelling was selected after taking informed written consent and fulfilling the inclusion criteria. Smears was taken by standard procedure and then was stained with papanicolaou stain and haematoxylin and eosine stain. The smears was classified into categories like benign, indeterminate, malignant and unsatisfactory. Sensitivity, specificity, positive and negative predictive value and accuracy of USG Guided FNAC was calculated and compared to already available data. Appropriate statistical analysis was done to make comparison between final histopathological findings with initial USG Guided FNAC findings. Result: During the study period a total 73 were found eligible for USG Guided FNAC. Most of the patients (52%) were from 20-39 years age group. Among them 67.12% were female and rest (32.87%) were male. In this government hospital 75.34% were from low income group. ......

TFL perforator flap – complementing and completing the ALT-AMT flap axis.

Background: Antero-lateral thigh flap (ALT) is the most common soft tissue flap used for microvascular reconstruction of head and neck. Its harvest is associated with some unpredictability due to variability in perforator characteristics, injury or unfavorable configuration for complex defects. Antero-medial thigh flap (AMT) is an option, but the low incidence and thickness restricts its utility. TFL perforator flap (TFLP) is an excellent option to complement ALT. Its perforator is consistent, robust, in vicinity and lends itself with ALT perforator, to large conjoint flap, chimeric designs and possible two free flap harvest from the same thigh. Methods: Analysis of 29 cases with a free flap for head neck reconstruction with an element of TFLP. Results: All cases were primarily planned for an ALT reconstruction. There was absence of the ALT perforator in 16 cases but a sizable TFL perforator was available. In 13 cases the complex defect warranted use of both ALT plus TFL in a conjoint (5), chimeric (5) and multiple (3) free flaps manner. Most common perforator location was septo-cutaneous between the TFL and Gluteus Medius. There was complete flap loss in two cases and partial necrosis in two. No adjuvant therapy was delayed. Conclusion: TFLP can be used to counter ALT/AMT unavailability, injury, suboptimal quality or need of a thicker flap. Chimeric ALT-TFL can be harvested for large, complex, multicomponent and multidimensional defects. We recommend, harvesting flaps from the thigh with a non-committal straight line incision initially, perceiving ALT-AMT-TFL perforators as a unit.

Post-traumatic Central or Axial atlantoaxial dislocation (CAAD) presenting with ‘atypical’ symptoms- Analysing the role of dynamic imaging on the basis of experience with 14 patients treated by atlantoaxial fixation surgery

This is a report of a series of 14 patients who presented with a range of 'atypical' cranial, spinal and systemic symptoms that started after they suffered relatively severe injury to the head and/or neck several months or years prior to the surgical treatment. Implications of diagnosing and treating central or axial atlantoaxial instability (CAAD) is discussed. Role of dynamic rotatory and lateral head tilt imaging in the diagnosis and treatment is analysed. There were 7 males and 7 females and their ages ranged from 21 to 64 years (average 42 years). Due to the severity of presenting neurological and non-neurological symptoms, all patients lost their occupation and were heavily dependent on painkillers and/or antidepressant drugs. In addition to other tell-tale clinical and radiological evidence, diagnosis of CAAD was made based on facetal alignments on lateral profile imaging in neutral head position. Dynamic head flexion-extension, lateral head tilt and neck rotation imaging confirmed and subclassified CAAD. All patients underwent atlantoaxial fixation surgery. A personalized self-assessment clinical scoring parameter and the WHODAS 2.0 was used to evaluate the outcome. One patient did not follow-up after surgery. At a minimum follow-up of 6 months after atlantoaxial fixation surgery, there was relief from all major symptoms in the rest of 13 patients. Diagnosing and treating CAAD can have 'major' therapeutic implications in patients presenting with progressively worsening disabling clinical symptoms following relatively severe head/neck trauma.

A Lightweight Model of Underwater Object Detection Based on YOLOv8n for an Edge Computing Platform

The visual signal object detection technology of deep learning, as a high-precision perception technology, can be adopted in various image analysis applications, and it has important application prospects in the utilization and protection of marine biological resources. While the marine environment is generally far from cities where the rich computing power in cities cannot be utilized, deploying models on mobile edge devices is an efficient solution. However, because of computing resource limitations on edge devices, the workload of performing deep learning-based computationally intensive object detection on mobile edge devices is often insufficient in meeting high-precision and low-latency requirements. To address the problem of insufficient computing resources, this paper proposes a lightweight process based on a neural structure search and knowledge distillation using deep learning YOLOv8 as the baseline model. Firstly, the neural structure search algorithm was used to compress the YOLOv8 model and reduce its computational complexity. Secondly, a new knowledge distillation architecture was designed, which distills the detection head output layer and NECK feature layer to compensate for the accuracy loss caused by model reduction. When compared to YOLOv8n, the computational complexity of the lightweight model optimized in this study (in terms of floating point operations (FLOPs)) was 7.4 Gflops, which indicated a reduction of 1.3 Gflops. The multiply–accumulate operations (MACs) stood at 2.72 G, thereby illustrating a decrease of 32%; this saw an increase in the AP50, AP75, and mAP by 2.0%, 3.0%, and 1.9%, respectively. Finally, this paper designed an edge computing service architecture, and it deployed the model on the Jetson Xavier NX platform through TensorRT.

Detection and classification of mandibular fractures in panoramic radiography using artificial intelligence.

This study aimed to assess the performance of a deep learning algorithm (YOLOv5) in detecting different mandibular fracture types in panoramic images. This study utilized a dataset of panoramic radiographic images with mandibular fractures. The dataset was divided into training, validation, and testing sets, with 60%, 20%, and 20% of the images, respectively. An equal number of control panoramic radiographs, which did not contain any fractures, were also randomly distributed among the three sets. The YOLOv5 deep learning model was trained to detect six fracture types in the mandible based on the anatomical location including symphysis, body, angle, ramus, condylar neck, and condylar head. Performance metrics of accuracy, precision, sensitivity (recall), specificity, dice coefficient (F1 score), and area under the curve (AUC) were calculated for each class. A total of 498 panoramic images containing 673 fractures were collected. The accuracy was highest in detecting body (96.21%) and symphysis (95.87%), and was lowest in angle (90.51%) fractures. The highest and lowest precision values were observed in detecting symphysis (95.45%) and condylar head (63.16%) fractures, respectively. The sensitivity was highest in the body (96.67%) fractures and was lowest in the condylar head (80.00%) and condylar neck (81.25%) fractures. The highest specificity was noted in symphysis (98.96%), body (96.08%), and ramus (96.04%) fractures, respectively. The dice coefficient and AUC were highest in detecting body fractures (0.921 and 0.942, respectively), and were lowest in detecting condylar head fractures (0.706 and .812, respectively). The trained algorithm achieved promising performance metrics for the automated detection of most fracture types, with the highest performance observed in detecting body and symphysis fractures. Machine learning can provide a potential tool for assisting clinicians in mandibular fracture diagnosis.

Perspective] Delta Radiomics — Potential Role in Head Neck Cancer

INTRODUCTION: Delta radiomics is a tool used to assess the response of oncologic patients undergoing immunotherapy. It extracts high-dimensional quantitative features from medical images, providing information about cancer's phenotype, genotype, and tumoral microenvironment. This analysis could help avoid invasive procedures and help choose the most suitable therapeutic in multiple therapeutic options. Radiomics has gained interest as an imaging biomarker for predicting response to various immunotherapies. Delta radiomics assesses feature variations from one time point to another based on subsequent images, offering higher value for treatment-outcome prediction or patient stratification into risk categories. It has potential benefits for clinical endpoints in oncology, such as differential diagnosis, prognosis, treatment response prediction, and evaluation of side effects. Further research with prospective and multicentre studies is needed for clinical validation of delta radiomics approaches. STATEMENT OF CLINICAL SIGNIFICANCE: In head and neck oncology, delta radiomics can be used to enhance the precision of diagnosis, assess tumor response, forecast normal tissue toxicity, predict clinical outcome, and pinpoint characteristics for treatment modification. Patients' quality of life may be enhanced by it. It can support post-treatment surveillance. Additionally, it can support the delivery of individualized care based on a patient's reaction to medication and radiation.

The effectiveness of Q6 and PIPER 6-year-old models on quantification of the change of child sitting posture with AEB and its impact on child’s injures in frontal crash

Objective Automatic Emergency Braking (AEB) has a direct impact on the effectiveness of the restraint systems in providing protection toward child occupants. The objective is to evaluate the effectiveness of Q6 and PIPER 6-year-old models in predicting the kinematic responses of child models, and further to quantify and analyze the child injuries during a frontal crash with and without AEB. Methods The finite element model of a booster seat has been validated through a full vehicle test. Based on the validated finite element model, two sled test finite element models for the rear seat booster seat with Q6 and PIPER 6-year-old models were constructed. AEB condition was imposed on above the two models and the kinematic responses of sitting posture including head, neck and chest have been compared in detail. The peak head displacement and neck curvature of Q6 dummy and PIPER 6-year-old models have been compared with the test data from child volunteers. Based on the child model with better predictive capability for kinematic response under AEB, child injuries were evaluated and analyzed for the 50 km/h frontal crash test with and without AEB. Last, this study discussed the effects of internal neck and chest structure difference between Q6 and PIPER 6-year-old models on child kinematic response and the injury risks. Results Under AEB condition, PIPER 6-year-old model has higher head displacement and lower trunk displacement than Q6 dummy model, and the peak head displacement and neck curvature of PIPER 6-year-old model are similar to the test data of child volunteers. During the 50 km/h frontal crash simulation with pre-crash AEB, the HIC15, Head acceleration 3 ms, Nij decrease 43.7%, 19.6% and 28.8%, respectively and the chest deflection increases 15.5% compared to the simulation without AEB. Conclusions This study shows that PIPER 6-year-old model is more suitable for the quantification of sitting posture change under AEB due to its higher biofidelity. The pre-crash AEB can substantially reduce the head, neck injuries. But it also increases the chest injury due to the chest pre-compression. Future efforts are recommended to lower the child chest injury by integrating AEB with active pre-tensioning seatbelts.

Minimum library size determination for RapidPlan knowledge based planning system using multicriteria optimization.

The aim of this study was to determine the number of trade-off explored (TO) library plans required for building a RapidPlan (RP) library that would generate the optimal clinical treatment plan. We developed two RP models, one each for the two clinical sites, head neck (HN) and cervix. The models were created using 100 plans and were validated using 70 plans (VP) for each site respectively. Each of the two libraries comprising 100 TO plans were divided into five different subsets of library plans comprising of 20, 40, 60, 80, and 100 plans, leading to five different RP model for each site. For every validation patient, a TO plan (TO_VP) was created. For every patient, five RP-plans were automatically generated using RP models. The dosimetric parameters of the six plans (TO_VP + five RP-plans) were compared using Pearson correlation and Greenhouse-Geisser analysis. PTV D95% in six competing plans varied between 97.6±0.7% and 98.1±0.6% in HN cases and 98.8±0.3% and 99.0±0.4% in cervix cases. Overall, for both sites the mean variations in OAR doses or volumes were within 50cGy, 0.5% and 0.2cc between library plans, and if TO_VP was included the variations deteriorated to 180 cGy, 0.4% and 15cc. All OARs in both sites, except D0.1 ccspine, showed a statistically insignificant variation between all plans. Dosimetric variation among various output plans generated from five RapidPlan libraries is minimal and clinically insignificant. The optimal output plan can be derived from the least weighted library consisting of 20 plans. This article shows that, when the constituent plans are subjected to trade-off exploration, the number of constituent plans for a knowledge-based planning module is not relevant in terms of its dosimetric output.

Perspective] Delta Radiomics — Potential Role in Head Neck Cancer

INTRODUCTION: Delta radiomics is a tool used to assess the response of oncologic patients undergoing immunotherapy. It extracts high-dimensional quantitative features from medical images, providing information about cancer's phenotype, genotype, and tumoral microenvironment. This analysis could help avoid invasive procedures and help choose the most suitable therapeutic in multiple therapeutic options. METHOD: Radiomics has gained interest as an imaging biomarker for predicting response to various immunotherapies. Delta radiomics assesses feature variations from one time point to another based on subsequent images, offering higher value for treatment-outcome prediction or patient stratification into risk categories. CONCLUSION: It has potential benefits for clinical endpoints in oncology, such as differential diagnosis, prognosis, treatment response prediction, and evaluation of side effects. Further research with prospective and multicentre studies is needed for clinical validation of delta radiomics approaches. STATEMENT OF CLINICAL SIGNIFICANCE: In head and neck oncology, delta radiomics can be used to enhance the precision of diagnosis, assess tumor response, forecast normal tissue toxicity, predict clinical outcome, and pinpoint characteristics for treatment modification. Patients' quality of life may be enhanced by it. It can support post-treatment surveillance. Additionally, it can support the delivery of individualized care based on a patient's reaction to medication and radiation.

Feasibility and potential of intraoperative ultrasound in arthroscopy of femoroacetabular impingement

ABSTRACT This study aimed to evaluate the feasibility of using ultrasound for monitoring osteochondroplasty intraoperatively, determine the factors that interfere with ultrasound imaging and assess its influence on surgeon performance. Intraoperative ultrasonography was performed during osteochondroplasty in 39 cases of arthroscopy. The femoral head–neck junction (FHNJ) was evaluated using ultrasonography. Another 39 cases, which underwent conventional arthroscopy, were included in the control group. The C-arm was used in this group at the end of osteochondroplasty to confirm that no residual cam lesion remained. Pre- and postoperative Dunn radiographs and computed tomography (CT) scans were analyzed to determine the feasibility of ultrasound. Residual cam deformity was noted in eight cases under ultrasound. The FHNJ was not detected owing to ultrasound interference by air in three cases. No difference in the α angle measured in Dunn radiographs and the residual cam deformity rate of CT at the 1:00, 2:00 or 3:00 position was found between both groups. However, the α angle at the 3:00 position was greater in the ultrasound group than in the control group (44.4 ± 4.3° versus 41.3 ± 5.1°, P < 0.05), suggesting that more bone was preserved at 3:00 in the ultrasound group. No difference was found in the mean operation time. None of the patients experienced complications, such as wounds or intra-articular infections. Ultrasound is a safe method for assessing FHNJ during arthroscopy. It did not change the risk of residual cam deformity but positively affected the surgeon’s performance by reducing unnecessary bone removal.

Validation of the Cervical Torsion Test and Head Neck Differentiation Test in Patients with Peripheral Vestibular Hypofunction.

This study compared adults with peripheral vestibular hypofunction (VH) to healthy controls and assessed the sensitivity and specificity of the Cervical Torsion Test (CTT) and the Head Neck Differentiation Test (HNDT). This study aimed to determine whether neck problems affected primary outcomes. This cross-sectional study included adults from a specialist consultation for dizziness. VH had been diagnosed with the video Head Impulse Test. Exclusion criteria were conditions following head or neck trauma and diseases of the central nervous system. Sensitivity and specificity of the index tests were calculated, and regression analyses were performed to test for contributing factors. A total of 19 patients with VH and a historical cohort of 19 matched healthy controls were included. Most patients with VH (84.2%) experienced symptoms in at least 1 test component, compared to 5.2% of the control group. Of patients with VH, 78.9% had symptoms during the HNDT "en bloc" (en bloc = head and trunk rotated together) whereas only 26.3% reported symptoms during the CTT en bloc. Best discriminatory validity was found for the HNDT en bloc, with a sensitivity of 0.79 (95% CI = 0.54-0.94), a specificity of 0.86 (95% CI = 0.65-0.97), and a positive likelihood ratio of 5.79 (95% CI = 1.97-17.00). The number of symptoms of CTT "in torsion" (in torsion = trunk rotated actively with fixed head) was increased by a factor of 1.13 (95% CI = 1.01-1.27) for every additional point on the Neck Disability Index. The CTT and HNDT can serve as nonlaboratory tests in patients with dizziness. The HNDT en bloc has the best discriminatory validity, finding those with and those without VH. Symptom reproduction during torsion may help to identify when neck problems may contribute to dizziness. The HNDT en bloc may be useful for ruling VH in or out in patients with dizziness. Positive CTT and HNDT in torsion components may verify the likelihood of additional neck involvement.

Abstract LB156: Targeting epigenetic activity of beta-catenin/CBP impedes oral cancer progression

Abstract Head and neck cancer is a complex malignancy with its major anatomical subsite, cancer of the oral cavity, ranking among the most deadly and disfiguring cancers. Oral cancer presents primarily as HPV-negative oral squamous cell carcinoma (OSCC) whose etiology is associated with tobacco and alcohol use and for which there are limited treatments. Whereas immunotherapies, such as anti-PD-1 antibodies, have become a promising therapeutic option, only ~20% of head neck cancer patients benefit from anti-PD-1 immunotherapy. We and others have shown that non-mutational epigenetic reprogramming mediated by the β-catenin/CBP complex promotes aggressive cell phenotypes in OSCC by establishing open chromatin at the transcription start sites of genes associated with cancer stemness. Accordingly, pharmacological inhibition of this complex dramatically inhibits OSCC evolution in a syngeneic mouse model of OSCC. Here, we evaluated whether the inhibition of β-catenin/CBP epigenetic activity would enhance the effects of anti-PD-1 immunotherapy. We adapted a syngeneic mouse model of tobacco-associated oral carcinogenesis that utilizes a mouse cell line, 4MOSC1, derived from 4-nitroquinoline-1 oxide- (4NQO)-induced tongue tumors of C57BL/6J mice. After tumors developed for 7 days, mice were blindly separated into treatment cohorts (n=13, each) to receive vehicle control (PBS), monotherapy (either 10 mg/kg anti-PD-1 EOD IP, or 100 mg/kg E7386, a Wnt signaling pathway modulator, QD oral gavage) or combination therapy (anti-PD-1 + E7386). Tumor isografts were harvested 11 days post initiation of treatments and processed for histopathology, immunohistochemistry, and immunofluorescence analyses. Measurements of tumor volumes showed that combination therapy resulted in a statistically significant reduction by ~80% compared to control mice and that it surpassed tumor decrease by either monotherapy. These results were confirmed by histopathology analyses. Evaluation of tumor tissues by immunofluorescence revealed statistically significant decreases in Cbp, H3K4me3, Keratin 14, and Podoplanin expression in response to E7386 alone and in combination with anti PD-1. Collectively our results suggest that a combination therapy comprising anti PD-1 treatment with E7386-targeting β-catenin/CBP epigenetic signaling is likely to impede OSCC evolution to advanced disease. Supported by Eisai, Co Ltd Research Award (MAK), NIH 5R01 DE030350 (MAK, SM, XV) and 5R01 DE031413 (MVB). Citation Format: Emily Fisher, Anthony Spinella, Junji Matsui, Kenichi Nomoto, Xaralabos Varelas, Manish Bais, Maria Kukuruzinska. Targeting epigenetic activity of beta-catenin/CBP impedes oral cancer progression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB156.

Measurement proprieties of the CROM instrument for assessing head posture, neck retraction and protraction

BackgroundThe CROM instrument is widely used clinically and in research to measure neck range of motion. However, its measurement proprieties during the assessment of protraction and retraction movements were not examined so far. ObjectiveTo analyse the intra- and inter-rater reliability, the concurrent validity of the CROM for measuring head posture, retraction and protraction in healthy subjects. MethodsThirty-three asymptomatic subjects were recruited and assigned in a random order to one of two raters. After a 10-min break, they were examined by a second rater (Assessment 1). After a 30-min break, both raters repeated the examination (Assessment 2). The examination consisted of measuring the head posture, maximum head protraction and maximum retraction. Each movement was repeated 3 times and measured simultaneously with the CROM and with a 3D capture system laboratory. ResultsThe intra-rater reliability of the CROM was excellent for both raters for head posture and all head movements (ICC>0.9, 95% CI: 0.82–0.99, p < 0.01). The inter-rater reliability was excellent for head posture (ICC>0.95, 95% CI: 0.92–0.98, p < 0.01) and good-to-excellent for all movements at both time-points (ICC = 0.73–0.98, 95%CI: 0.45–0.99, p < 0.01). The validity analysis showed moderate-to-strong correlation between instruments for the head posture and head movements [(r) = -0.47 to −0.78), 95% CI: 0.99 to −0.24, p < 0.01]. ConclusionThe CROM instrument has good-to-excellent reliability and adequate validity for measuring cervical position and displacement in the sagittal plane.

Prevalence of Ear and Nasal Diseases in Bangladeshi Patients

Background: The magnitude of health problems related to ear and nose in Bangladesh has not been estimated in a larger scale and very little is known about the prevalence and types of ENT diseases. Commonest cause of hearing impairment in our country is middle ear infection. Conductive type of deafness mostly occurs due to otitis media with or without its complications. Goal of primary health eare services is to achieve "Sound hearing by 2030" will never be achieved if we could not find out possible association of middle ear disease with other health conditions. Objective: To determine the prevalence of ear and nasal diseases in Bangladeshi patients. Methods: Two hundred patients complaining of middle ear discharge and or nasal symptoms were included in this study, to see the association of COM with nasal disorders. This cross sectional study was conducted in Dhaka Medical College Hospital from July 2012 to June 2014.Sample was taken by purposive sampling. Sample was divided into four groups as exposed and diseased, exposed and not diseased, not exposed diseased and not exposed and not diseased. Results: Two hundred patients were studied in the department of ENT and Head Neck Surgery of Dhaka Medical College Hospital complaining of either COM or Sinonasal disease. Among them 107 were female and 93 were male and male female ratio was 1:1.15. On analyzing age distribution it was ranging from 10 years to 50 years with mean age 30±7.86% clustering around 25 years. This study revealed that 65 % of COM is in the age group of 10-30 years. Conclusion: A study on the prevalence of the Ear Nose throat and Head and Neck diseases in developing country like Bangladesh can provide basic data which can be relevant and beneficial to the development of medical ENT curriculum in the regional setup and subsequent medical practice.

Choosing Optimal Feeding Method in Head–Neck Cancer Patients Receiving Radiation: Percutaneous Endoscopic Gastrostomy Versus Nasogastric Tube—Is It Pertinent?

The current standard of care for locally-advanced head–neck cancer is multidisciplinary, using bimodality or trimodality therapy as appropriate. These patients are frequently malnourished either due to disease or due to treatment related toxicities. Both chemotherapy and radiotherapy are associated with acute and late toxicities which in turn exacerbate malnutrition in these patients. Malnutrition is found to be associated with poor survival outcomes. To maintain nutrition in such patients, enteral feeding can be done using either percutaneous endoscopic gastrostomy tube (PEG) or a nasogastric tube (NGT). Both PEG and NGT have been found effective in adequate maintenance of weight; however, both have their own set of advantages and disadvantages. Nutritional counselling forms an integral part of weight management during treatment and oral feeding should be encouraged in all unless contra-indicated.

A Controlled Variable Study of the Biomechanical Properties of the Proximal Femur before and after Cancellous Bone Removal.

The biomechanical characteristics of proximal femoral trabeculae are closely related to the occurrence and treatment of proximal femoral fractures. Therefore, it is of great significance to study its biomechanical effects of cancellous bone in the proximal femur. This study examines the biomechanical effects of the cancellous bone in the proximal femur using a controlled variable method, which provide a foundation for further research into the mechanical properties of the proximal femur. Seventeen proximal femoral specimens were selected to scan by quantitative computed tomography (QCT), and the gray values of nine regions were measure to evaluated bone mineral density (BMD) using Mimics software. Then, an intact femur was fixed simulating unilateral standing position. Vertical compression experiments were then performed again after removing cancellous bone in the femoral head, femoral neck, and intertrochanteric region, and data were recorded. According to the controlled variable method, the femoral head, femoral neck, and intertrochanteric trabeculae were sequentially removed based on the axial loading of the intact femur, and the displacement and strain changes of the femur samples under axial loading were recorded. Gom software was used to measure and record displacement and strain maps of the femoral surface. There was a statistically significant difference in anteroposterior displacement of cancellous bone destruction in the proximal femur (p < 0.001). Proximal femoral bone mass explained 77.5% of the strength variation, in addition proximal femoral strength was mainly affected by bone mass at the level of the upper outer, lower inner, lower greater trochanter, and lesser trochanter of the femoral head. The normal stress conduction of the proximal femur was destroyed after removing cancellous bone, the stress was concentrated in the femoral head and lateral femoral neck, and the femoral head showed a tendency to subside after destroying cancellous bone. The trabecular removal significantly altered the strain distribution and biomechanical strength of the proximal femur, demonstrating an important role in supporting and transforming bending moment under the vertical load. In addition, the strength of the proximal femur mainly depends on the bone density of the femoral head and intertrochanteric region.

Abstract 4695: Effect of fully human anti-PTGFRN antibody drug conjugate on head neck cancer cells and patient derived xenografts

Abstract Prostaglandin F2 Receptor Negative regulator, or PTGFRN, also known as FPRP is a 175 kDa transmembrane protein associated with metastatic characteristics of certain cancer types and a member of the tetraspanin family. PTGFRN expression is undetectable to low in normal tissues whereas it is elevated in several cancers such as head and neck, mesothelioma and medulloblastoma. PTGFRN has also been reported to be upregulated in many different types of cancer, increasingly so in metastatic cancer cells, compared to their non-metastatic counterparts PTGFRN expression has been reported to be a poor prognostic factor for glioblastoma making it a potential novel cancer therapeutic target. We have previously shown that PTGFRN is an internalizable cell surface protein making it suitable for targeting by antibody drug conjugate (ADC). We have developed fully human monoclonal antibodies to PTGFRN by immunizing humanized transgenic TC mice with human PTGFRN. Within 60 days from the start of immunization we were able to select several fully human anti-PTGFRN monoclonal antibodies that were examined by several functional assays that included flow binding, internalization, affinity determination and cell killing as antibody drug conjugates. Several monoclonal antibodies were selected and evaluated for their ability to inhibit tumor formation in several cancers. Selected antibodies were then conjugated to duocarmycin by a cleavable linker. The present study proposed to examine the effect of one such anti-PTGFRN ADC on head and neck cancer cell lines and patient derived xenografts that had been analyzed for their PTGFRN expression by western blot analysis using anti-PTGFRN antibody. Cells lines and PDX that were positive for PTGFRN expression were used to examine the effect of anti-PTGFRN ADC on their in vitro and in vivo proliferation. The data show that anti-PTGFRN ADC inhibits tumor formation in a dose-dependent fashion. These data also establish PTGFRN as cancer druggable target and the selected fully human anti-PTGFRN antibody as an attractive antibody for the development of new antibody drug conjugate in Oncology. These data also emphasize the potential of humanized transgenic TC mice for the development of fully human monoclonal antibodies, thus bypassing the need for humanization and affinity maturation required by other humanized mice or phase display. Citation Format: Jorge Marquez, Jianping Dong, Mitsuo Oshimura, Jun Hayashi, Ginette Serrero. Effect of fully human anti-PTGFRN antibody drug conjugate on head neck cancer cells and patient derived xenografts [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4695.

Understanding the role of head size and neck length in micromotion generation at the taper junction in total hip arthroplasty

Modular hip implants allow intra-operative adjustments for patient-specific customization and targeted replacement of damaged elements without full implant extraction. However, challenges arise from relative micromotions between components, potentially leading to implant failure due to cytotoxic metal debris. In this study magnitude and directions of micromotions at the taper junction were estimated, aiming to understand the effect of variations in head size and neck length. Starting from a reference configuration adhering to the 12/14 taper standard, six additional implant configurations were generated by varying the head size and/or neck length. A musculoskeletal multibody model of a prothesized lower limb was developed to estimate hip contact force and location during a normal walking task. Following the implant assembly, the multibody-derived loads were imposed as boundary conditions in a finite element analysis to compute the taper junction micromotions as the relative slip between the contacting surfaces. Results highlighted the L-size head as the most critical configuration, indicating a 2.81 μm relative slip at the mid-stance phase. The proposed approach enables the investigation of geometric variations in implants under accurate load conditions, providing valuable insights for designing less risky prostheses and informing clinical decision-making processes.

Analysis of Domain Addressed and Subdivisions of Anatomy Emphasized in Spotting Stations in Anatomy Part of First Professional MBBS Examination

Introduction: Assessment of any educational program should implement purpose of the learning objectives. Learning objectives are prepared with the help of several models such as SOLO (Structure of observed learning Outcomes) taxonomy, Bloom’s Taxonomy etc. The most commonly used classification system is “Bloom’s taxonomy to develop learning objectives” which describes the domains of educational objectives and divides the domains into three categories a) cognitive domain b) psychomotor domain c) affective domain. Objectives: To observe the domains of the questions of soft part-portion of Spotting stations to fulfill the learning objectives set by the curriculum in Anatomy professional examination in the background of Bloom’s Taxonomy. The research also tries to find out the subdivisions of Anatomy preferred more and regions of Gross Anatomy more emphasized in soft part-portion of Spotting stations. Methods: This cross sectional study held in the Department of Anatomy in Armed Forces Medical College (AFMC) from August 2015 to December 2018. Data (questions of soft part-portion of Spotting stations and ‘answer key’s) are collected from seven different medical colleges affiliated under Dhaka University. A total fifty-two day’s questions with ‘answer key’s are taken for the study from the first professional examination held on May 2013 and May 2014. For the purpose of the study each question is divided into ‘Item’, ‘Part’s and ‘Segment’s. Moreover verbs of the segments are then analyzed in the form of ‘statement’, ‘list’ and ‘single name’ and Anatomy is subdivided into Gross Anatomy, Histology and Developmental Anatomy. Result: A total 774 items, 1571 parts, 2048 segments are analyzed. The verbs used to address the levels of cognitive domain in the questions reveals that ‘identification’ is mostly (76.62%) used in supplied figure followed by radiology (52.05%) model (41.89%) viscera (38.82%) and dissection (24.95%) stations. ‘Statement’ mostly used as verb by dissection (37.28%) and minimum in supplied figure (11.6%) stations. Similarly ‘list’ is mostly used in viscera (23.14%) and ‘single name’ is mostly used verb in dissection stations. Maximum (89.2%, 92.47%, 90.54% and 81.82%) questions are asked from Gross Anatomy subdivision in viscera, radiology, model and in supplied figure stations respectively. In case of viscera stations about one third (34.62%) and one fourth (25.62%) questions are from the thorax and abdomen proper respectively and around 15% questions cover pelvis, (10.54%) head neck, (12.34%) and brain (16.88%) respectively. Nearly half (46%) of the figure station use supplied figures as a ‘tool’. Maximum (39%) figures are used from brain where supplied figures are used as a ‘tool’ and no figure used from lower limb. When instructed to ‘draw and label’, 50% are from region of brain and less than 20% from other regions. Conclusion: From the findings it can be easily perceived that though Spotting examination is part of practical examination but in our country but it mainly involves in assessing factual knowledge of Anatomy which can hardly meet the demand of the objectives set by the curriculum. JAFMC Bangladesh. Vol 19, No 1 (June) 2023: 59-65