Soft Tissue Anatomy Research Articles

Differential performance of aqueous- and ethylic-Lugol's iodine stain to visualize anatomy in μCT-scanned vertebrates.

Museum specimens are an increasingly important tool for studying global biodiversity. With the advent of diffusible iodine-based contrast-enhanced computed tomography (diceCT), researchers can now visualize an organism's internal soft tissue anatomy without the need for physical dissection or other highly destructive sampling methods. However, there are many considerations when deciding which method of staining to use for diceCT to produce the best gray-scale contrast for facilitating downstream anatomical analyses. The general lack of direct comparisons among staining methodologies can make it difficult for researchers to determine which approaches are most appropriate for their study. Here, we compare the performance of ethylic-Lugol's iodine solution with aqueous-Lugol's staining solution across several vertebrate orders to assess differential imaging outcomes. We found that ethylic-Lugol's is better for visualizing muscle attachment to bone but provides overall lower contrast between soft tissue types. Comparatively, aqueous-based Lugol's provides high-contrast imaging among soft tissue types, although bone is more difficult to discern. We conclude that the choice of staining methodology largely depends on the type of anatomical data the researcher wishes to collect, and we provide a decision-based framework for assessing which staining methodology (ethylic or aqueous) is most appropriate for desired imaging results.

Validation of a novel AI-based automated multimodal image registration of CBCT and intraoral scan aiding presurgical implant planning.

The objective of this study is to assess accuracy, time-efficiency and consistency of a novel artificial intelligence (AI)-driven automated tool for cone-beam computed tomography (CBCT) and intraoral scan (IOS) registration compared with manual and semi-automated approaches. A dataset of 31 intraoral scans (IOSs) and CBCT scans was used to validate automated IOS-CBCT registration (AR) when compared with manual (MR) and semi-automated registration (SR). CBCT scans were conducted by placing cotton rolls between the cheeks and teeth to facilitate gingival delineation. The time taken to perform multimodal registration was recorded in seconds. A qualitative analysis was carried out to assess the correspondence between hard and soft tissue anatomy on IOS and CBCT. In addition, a quantitative analysis was conducted by measuring median surface deviation (MSD) and root mean square (RMS) differences between registered IOSs. AR was the most time-efficient, taking 51.4 ± 17.2 s, compared with MR (840 ± 168.9 s) and SR approaches (274.7 ± 100.7 s). Both AR and SR resulted in significantly higher qualitative scores, favoring perfect IOS-CBCT registration, compared with MR (p = .001). Additionally, AR demonstrated significantly superior quantitative performance compared with SR, as indicated by low MSD (0.04 ± 0.07 mm) and RMS (0.19 ± 0.31 mm). In contrast, MR exhibited a significantly higher discrepancy compared with both AR (MSD = 0.13 ± 0.20 mm; RMS = 0.32 ± 0.14 mm) and SR (MSD = 0.11 ± 0.15 mm; RMS = 0.40 ± 0.30 mm). The novel AI-driven method provided an accurate, time-efficient, and consistent multimodal IOS-CBCT registration, encompassing both soft and hard tissues. This approach stands as a valuable alternative to manual and semi-automated registration approaches in the presurgical implant planning workflow.

Validation of a surgical simulator and establishment of quantitative performance thresholds—RealSpine simulation system for open lumbar decompressions

BACKGROUND CONTEXTThe majority of surgical training is conducted in real-world operations. High-fidelity surgical simulators may provide a safer environment for surgical training. However, the extent that it reflects real-world operations and surgical ability is often poorly characterized. PURPOSE(1) Assess the validity and fidelity of a surgical simulator; (2) Examine the quantitative relationship between simulation performance and markers of real-world ability; (3) Establish thresholds for surgical expertise, and estimate their external validity and accuracy. STUDY DESIGN/SETTINGA cohort study of surgeons at a British neurosurgical center. STUDY SAMPLETen early-career “novice” surgeons and 8 board-certified “expert” neurosurgeons. OUTCOMES MEASURES(1) Face and content validity, and visual and haptic fidelity; (2) Construct validity; (3) Predictive and discriminative utility of quantitative performance thresholds. METHODSParticipants performed unilateral lumbar decompressions on high-fidelity spinal simulators that replicate the bony and soft tissue anatomy along with physiological processes such as bleeding and CSF leaks. Operating times, measured from first surgical action to either self-perceived satisfactory decompression or the end of allocated time, were recorded. The performance was also assessed independently by 2 blinded spinal subspecialist neurosurgeons using OSATS, a validated surgical assessment tool that utilizes 5-point scales on a variety of technical domains to grade the overall technical proficiency. Validity and fidelity were assessed by expert neurosurgeons using quantitative questionnaires. Construct validity was assessed by ordinal regression of simulation performance against real-world surgical grade and portfolio. Thresholds of expert status by simulation performance was established, and their predictive and discriminative utility assessed by crossvalidation accuracy and AUC-ROC. RESULTSOperating time and expert assessments of simulation performance (OSATS) were strong and significant prdictors of surrogate markers of real-world surgical ability. The thresholds for expert status were operating time of 15 minutes and modified OSATS score of 15/20. These thresholds predicted expert status with 84.2% and 71.4% accuracy respectively. Strong discriminative ability was demonstrated by AUC-ROC of 0.95 and 0.83 respectively. All expert surgeons agreed that RealSpine simulators demonstrate high face validity, and high visual and haptic fidelity, with overall scores showing statistically significant agreement on these items (all scores at least 4/5, p<.0001). There was less consensus on content validity, but with still significant overall agreement (average score: 3.75/5, p=.023). CONCLUSIONSReal-world surgical ability and experience can be accurately predicted by defining objective quantitative thresholds on high-fidelity simulations. The thresholds established here, along with other data presented in this paper, may inform objectives and standards to be established in a spinal surgical training curriculum.

MRI findings of closed hand injuries in adolescent goalkeepers: a case-based review.

Soccer-related injuries in youth goalkeepers are underrepresented in epidemiological studies, despite goalkeepers experiencing distinct types of upper limb injuries and training loads compared to outfield players. Digit injuries are particularly prevalent, with up to five times more upper extremity injuries reported in this position. Such injuries can lead to interphalangeal joint instability and an increased risk of reinjury. Mechanisms of injury include falls, axial loading of digits, and rotational force due to grasping activities. The proximal interphalangeal joint is the most frequently injured in sports, followed by the metacarpophalangeal joint of the thumb. Achieving precise diagnosis can be challenging due to the complex soft-tissue anatomy of the hand. Radiologists play a crucial role in accurate diagnosis through imaging studies, enabling timely treatment. This article focuses on closed traumatic finger and thumb injuries in adolescent goalkeepers, describing injury mechanisms and outlining relevant MRI features to facilitate proper clinical approaches for diagnosis based on imaging findings.

Late Ordovician eurypterid preserves oldest euchelicerate musculature in pyrite.

Pyritization of soft tissues of invertebrates is rare in the fossil record. InNewYork State, it occurs in black shales of the Lorraine Group (Late Ordovician), the best-known example of which is Beecher's Trilobite Bed. Exceptional preservation at the quarry where this bed is exposed allowed detailed examination of trilobite and ostracod soft-tissue anatomy. Here, we present the first example of a eurypterid (sea scorpion) currently ascribed to Carcinosomatidae from this deposit that also preserves the first evidence for mesosomal musculature in eurypterids. This specimen demonstrates thateurypterid musculature can be preserved in pyrite and evidences the oldest example of euchelicerate muscles within the fossil record. Sulfur isotope data illustrate that pyrite rapidly replicated muscle tissue in the early burial environment, prior to the pyritization of biomineralized exoskeleton and cuticular trilobite limbs. This discovery therefore expands thelimited fossil record of euchelicerate musculature, while extending the taphonomic scope for preservation of detailed internal structures, more broadly, within arthropods.

Extraction Socket Seal Technique for Socket Preservation after Tooth Extraction: An Innovative Approach.

Background and objectives: Tooth extraction triggers the loss of surrounding alveolar soft tissue and bone. Numerous socket preservation techniques have been used by clinical surgeons; the issue with all existing techniques is the loss of soft tissue anatomy, resulting in a flat soft tissue architecture. Our study introduces an innovative ridge preservation technique that addresses this problem; it involved using an anatomically shaped composite resin lid that acts as a graft sealant and an approach for maintaining the soft tissue cervical profile. Material and Methods: The Extraction Socket Seal (ESS) technique was applied for 23 patients for socket preservation; atraumatic extraction of hopeless tooth was performed. The extraction socket was filled up with bone grafting material. After that, the composite resin lid, which was fabricated by the Cervico system was placed into the extraction socket. Finally, the lid was connected to the adjacent teeth with an adhesive system and composite resin material. The patients were evaluated for a three-month interval for any complications and success of Extraction Socket Seal (ESS) technique. The data were tested by descriptive data analysis using the Statistical Package for Social Sciences (SPSS, version 29). Results: The proposed technique has been successfully performed in twenty-three cases; 13 cases were male and 10 cases were female; and the mean age of all cases was 32 years. Extraction Socket Seal (ESS) technique utilizing a composite resin lid fabricated from the Cervico system was used as socket sealant placed directly to cover the bone graft, and we found that it provided an excellent “barrier” for the graft without any unwanted complications. After three months, radiographs showed good bone healing, and the mean socket soft tissue healing score was 4 (Very good wound healing), and most importantly the soft tissue architecture and shape were well preserved. Conclusions: We concluded that the Extraction Socket Seal (ESS) technique offers a very simple and time-saving technique for alveolar ridge preservation after tooth extraction for both anterior and posterior extraction sockets, and it provides a good seal for the graft material and the soft tissue anatomy was well preserved. Keywords: Alveolar ridge preservation, Extraction Socket Seal, ESS, Delayed implant placement, Socket preservation, Tooth extraction.

Trismus caused by migration of orthodontic archwire into the infratemporal fossa: a case report.

Soft tissue injuries are known complications of orthodontic treatment. Most of the injuries are mild, but severe complications can arise from deeper penetration or dislodgement of brackets and other foreign bodies into the surrounding tissues of the oropharynx and infratemporal fossa. The patient, accompanied by his parents, presented to the Children's Emergency Department with the concern of gradual limitation of mouth opening and eventual trismus, which occurred over a span of 2 weeks. The patient presented with trismus and slight discomfort at the left cheek region. He reported a history of gradual limitation to his mouth opening 2 weeks prior. He was wearing upper and lower fixed orthodontic appliances and the left distal end of the maxillary archwire was found to have migrated into the left infratemporal fossa. Left medial pterygoid muscle inflammation, or bleeding and haematoma formation, or infection within the infratemporal region. The maxillary archwire was removed in the Children's Emergency Department and a computed tomography (CT) scan performed subsequently confirmed the diagnosis of left medial pterygoid muscle inflammation. The patient was started on an intravenous (IV) antibiotic and a 2-day course of IV dexamethasone to reduce the muscle inflammation. By the second day, the patient was able to achieve a mouth opening of 6 mm, and by the second week, the mouth opening had returned to normal. The potential risk of soft tissue injury and complications from orthodontic treatment is generally mild and limited. Soft tissue injuries can be avoided with careful management by the operator with the proper precautions taken. Clinicians should be familiar with the surrounding soft tissue anatomy and be aware of the potential for more severe complications and provide management or referral to the appropriate specialty accordingly.

Investigating the role connective tissue fibroblasts play in the altered muscle anatomy associated with the limb abnormality, Radial Dysplasia.

Radial dysplasia (RD) is a congenital upper limb birth defect that presents with changes to the upper limb anatomy, including a shortened or absent radius, bowed ulna, thumb malformations, a radially deviated hand and a range of muscle and tendon malformations, including absent or abnormally shaped muscle bundles. Current treatments to address wrist instability caused by a shortened or absent radius frequently require an initial soft tissue distraction intervention followed by a wrist stabilisation procedure. Following these surgical interventions, however, recurrence of the wrist deviation remains a common, long-term problem following treatment. The impact of the abnormal soft connective tissue (muscle and tendon) anatomy on the clinical presentation of RD and the complications following surgery are not understood. To address this, we have examined the muscle, fascia and the fascial irregular connective tissue (ICT) fibroblasts found within soft connective tissues, from RD patients. We show that ICT fibroblasts isolated from RD patients are functionally abnormal when compared to the same cells isolated from control patients and secrete a relatively disordered extracellular matrix (ECM). Furthermore, we show that ICT fibroblast dysfunction is a unifying feature found in RD patients, even when the RD clinical presentation is caused by distinct genetic syndromes.

Cervical anatomy and its relation to foraging habits in aquatic birds (Aves: Neornithes: Neoaves).

Birds have extremely flexible necks, which help in their search for food. However, studies on the variation in bird cervical anatomy and its relationship with foraging are rare, despite the different habits presented between species. Here, we analyze the anatomy of the neck of aquatic birds and relate it to their foraging strategies. We dissected specimens representing four species of Charadriiformes, 11 species of Phaethoquornithes, and two specimens belonging to the outgroup Telluraves. We chose to emphasize Charadriiformes and Phaethoquornithes because they present several strategies that require cervical mobility and stability. We note that vertebral anatomy and dimensions vary, which affects the shape and size of the soft tissues attached throughout the neck. The synovial cartilage present in the articulatio intercorporalis represents an additional length in the neck, however, this is not longer than that observed in animals with intervertebral discs. Our analysis indicates that birds have a prevalence of dorsoventral movements in the middle of the neck and lateral and rotational movements near the base of the neck, while the region near the head presents a wide range of movement in all directions. Cervical ligaments and muscles throughout the neck provide stability in all segments, although the robustness of the soft tissues indicates that the most caudal portion of the neck is the most stable. The vertebral and soft tissue anatomy is consistent with the extensive mobility in pitching, yaw, and roll movements performed mainly by the head and first segment of the neck during the different foraging of the analyzed birds. Furthermore, the muscles closer to the skull are robust and allow the execution of a variety of habits to capture food in different species. The subsequent cervical segments present differences that explain their reduction in mobility, but they are equally stable.

Post-Prosthetic Surgery: Using Complete Denture Prosthesis for Propriotous Outcome During Vestibuloplasty By IJISRT

Prosthodontic rehabilitation of edentulous patient is quite challenging. The success of complete dentures depends on many factors among which the anatomical factors play a major role. For functioning of complete denture in harmony there should exist proper stability, support and retention. Any compromising factors among them which might probably result in failure of prosthesis. As soft tissue anatomy in which the denture borders are placed are movable. It’s imperative that the prosthesis will not hamper the tissue mobility to maintain retention. Sometimes alteration of the soft tissue anatomy may greatly increase the retention of the fabricated prosthesis. In this article we are presenting a clinical tip to improvise the final outcome and prognosis of prosthetic surgery after delivering the final prosthesis.

Results of an Artificial Intelligence-Based Image Review System to Detect Patient Misalignment Errors in a Multi-institutional Database of Cone Beam Computed Tomography-Guided Radiation Therapy

PurposePresent knowledge of patient setup and alignment errors in image-guided radiotherapy (IGRT) relies on voluntary reporting, which is thought to underestimate error frequencies. A manual retrospective patient-setup misalignment error search is infeasible due to the bulk of cases to be reviewed. We applied a deep learning-based misalignment error detection algorithm (EDA) to perform a fully-automated retrospective error search of clinical IGRT databases and determine an absolute gross patient misalignment error rate. MethodsThe EDA was developed to analyze the registration between planning scans and pre-treatment CBCT scans, outputting a misalignment score ranging from 0 (most unlikely) to 1 (most likely). The algorithm was trained using simulated translational errors on a dataset obtained from 680 patients treated at two radiotherapy clinics between 2017 and 2022. A receiver operating characteristic analysis was performed to obtain target thresholds. A DICOM Query and Retrieval software was integrated with the EDA to interact with the clinical database and fully automate data retrieval and analysis during a retrospective error search from 2016-2017 and 2021-2022 for the two institutions, respectively. Registrations were flagged for human review using both a hard-thresholding method and a prediction trending analysis over each individual patient's treatment course. Flagged registrations were manually reviewed and categorized as errors (>1cm misalignment at the target) or non-errors. ResultsA total of 17,612 registrations were analyzed by the EDA, resulting in 7.7% flagged events. Three previously reported errors were successfully flagged by the EDA and four previously-unreported vertebral body misalignment errors were discovered during case reviews. False positive cases often displayed substantial image artifacts, patient rotation, and soft-tissue anatomy changes. ConclusionOur results validated the clinical utility of the EDA for bulk image reviews, and highlighted the reliability and safety of IGRT, with an absolute gross patient misalignment error rate of 0.04% ± 0.02% per delivered fraction.

Analysis of Different Vertical and Horizontal Smile Characteristics

BACKGROUND: Improving smile aesthetics is the main reason patients seek different treatments. AIM: This study aimed to evaluate some of the smile characteristics in patients with completed orthodontic treatment and patients with different types of dentoalveolar malocclusion using the method of photogrammetric analysis. MATERIALS AND METHODS: The sample consisted of 52 young adults aged 16–35 years. A standardized smile analysis was used to evaluate ten smile characteristics. Two frontal digital photographs were taken for each individual, one at rest and the other with a posed smile. RESULTS: A student’s t-test was used to evaluate the differences between the mean values of the smile characteristics of each type of malocclusion in untreated and treated patients. Comparing the characteristics of the smile in the study groups of treated and untreated patients with a subgroup of Class I and Class III malocclusion, no significant difference was observed in the mean values of the studied parameters. A statistically significant difference was observed only in the mean values of upper incisor exposure and left buccal corridor between untreated and treated patients with class II malocclusion. CONCLUSION: Knowledge of the correlation between hard and soft-tissue anatomy and smile esthetics has important clinical significance; therefore, the components of the smile should be considered as a guide to assist in orthodontic diagnosis and treatment planning.

Immediate implant in the esthetic area when immediate loading is not an option: a clinical case report

Aims: Tooth extraction in the frontal area is associated with significant bone resorption, especially at sockets presenting with a thin buccal wall, such as most of the maxillary incisors. In the case of favorable residual hard and soft tissue anatomy, immediate implant placement in the esthetic area might be an opportunity to drive the alveolus healing course in the desired direction. Case presentation: In this clinical case, a fractured upper central incisor was replaced by an immediate two-piece implant covered with a healing screw. After 3 months, the implant was restored. The facial and interdental soft tissue was maintained with appreciable success at the 3-year follow-up visit. Conclusion: When immediate loading of the implant is not an option and the fresh extraction socket presents with fair soft tissue quality, the use of an interim healing screw might help sustain and prevent the shrinkage of peri-implant tissues. This simple technique might be a valuable option when there is no indication for adjunctive hard or soft tissue grafting or immediate loading feasibility conditions.

The Pediatric Neuroradiologist's Practical Guide to Capture and Evaluate Pre- and Postoperative Velopharyngeal Insufficiency.

Up to 30% of children with cleft palate will develop a severe speech disorder known as velopharyngeal insufficiency. Management of velopharyngeal insufficiency typically involves structural and functional assessment of the velum and pharynx by endoscopy and/or videofluoroscopy. These methods cannot provide direct evaluation of underlying velopharyngeal musculature. MR imaging offers an ideal imaging method, providing noninvasive, high-contrast, high-resolution imaging of soft-tissue anatomy. Furthermore, focused-speech MR imaging techniques can evaluate the function of the velum and pharynx during sustained speech production, providing critical physiologic information that supplements anatomic findings. The use of MR imaging for velopharyngeal evaluation is relatively novel, with limited literature describing its use in clinical radiology. Here we provide a practical approach to perform and interpret velopharyngeal MR imaging examinations. This article discusses the velopharyngeal MR imaging protocol, methods for interpreting velopharyngeal anatomy, and examples illustrating its clinical applications. This knowledge will provide radiologists with a new, noninvasive tool to offer to referring specialists.

Translucent monolithic zirconia titanium-supported FP1 full-arch prosthesis: A novel proof of concept to address esthetic, functional, and biologic challenges.

Despite the wide clinical use of translucent zirconia for full-arch implant prostheses, reduced flexural strength and fracture toughness compared with high-strength opaque zirconia needs to be addressed. A novel proof of concept for FP1 full-arch prosthesis featured by translucent monolithic zirconia and titanium framework was presented. Computer-guided implant planning and surgery were executed and digitally designed FP1 temporary prosthesis prefabricated. Implant and prosthetic placement were achieved with a set of three-dimensional (3D)-printed templates. Implants were immediately loaded. After 4 months intraoral optical scan was taken to record implant coordinates, soft tissue anatomy, and temporary FP1 prosthesis. A novel digital workflow was used to design and mill overlaying translucent zirconia and anatomically shaped titanium framework with a scalloped soft-tissue interface. Final FP1 prosthesis was assembled cementing zirconia jacket on titanium counterpart. Translucent zirconia supported by titanium framework can address esthetic and mechanical requirements of FP1 full-arch prosthesis, minimizing risk of fracture and providing a rigid and passive joint with supporting implants. The smooth and highly polished titanium surface with an anatomic design, tightly matching scalloped soft tissue interface, can limit food impaction, air and saliva leakage and contribute to overall biologic integration of FP1 full-arch prosthesis. Translucent monolithic zirconia featured with anatomically shaped titanium framework with scalloped transmucosal part, combining a pleasant esthetic outcome with increased flexural strength and fracture toughness, may be indicated to increase the clinical performance of FP1 full-arch prosthesis.

Determination of acceptable Hounsfield units uncertainties via a sensitivity analysis for an accurate dose calculation in the context of prostate MRI-only radiotherapy

Radiation therapy is moving from CT based to MRI guided planning, particularly for soft tissue anatomy. An important requirement of this new workflow is the generation of synthetic-CT (sCT) from MRI to enable treatment dose calculations. Automatic methods to determine the acceptable range of CT Hounsfield Unit (HU) uncertainties to avoid dose distribution errors is thus a key step toward safe MRI-only radiotherapy. This work has analysed the effects of controlled errors introduced in CT scans on the delivered radiation dose for prostate cancer patients. Spearman correlation coefficient has been computed, and a global sensitivity analysis performed following the Morris screening method. This allows the classification of different error factors according to their impact on the dose at the isocentre. sCT HU estimation errors in the bladder appeared to be the least influential factor, and sCT quality assessment should not only focus on organs surrounding the radiation target, as errors in other soft tissue may significantly impact the dose in the target volume. This methodology links dose and intensity-based metrics, and is the first step to define a threshold of acceptability of HU uncertainties for accurate dose planning.

Anatomy-driven complexity classification for soft-tissue tunneling procedures.

The tunnel technique (TUN) preserves the integrity of the papilla by creating envelope flaps that allow for the insertion of a connective tissue graft, and/or biomaterials. (1) A comprehensive overview of tunneling flap procedures in the treatment of gingival recessions (GRs) for soft tissue coverage is presented and (2) A classification system for soft and hard tissue anatomy of GR sites which may aid the clinician in determining the surgical complexity is being introduced. A novel clinical classification system is proposed to illustrate complexity levels determined by soft and hard tissue anatomy of GR sites such as the mucogingival junction proximity to the gingival margin, bone morphotype, and mucosal margin thickness. TUN is highly effective in treating single/multiple GRs. Its limitations are related to variability in surgical site anatomy and operator expertise. A classification system based on anatomical soft and hard tissue variations has been proposed to help identify complexity levels encountered during tunneling procedures. Site-related factors directly impact the surgical variables related to tissue trauma, flap tension, soft tissue management, muscle pull, and wound stability during the healing of gingival recessions (GRs). The achievement of expedited and favorable wound healing is crucial to obtaining quantitative and qualitative success in the treatment of GR and the long-term stability of root coverage. A classification system based on anatomical soft and hard tissue variations has been proposed to facilitate tunneling procedures while respecting surgical principles.

Modeling and Simulation of Robotic Palpation to Detect Subsurface Soft Tissue Anomaly for Presurgical Assessment

Abstract Surgical Haptics is an emergent field of research to integrate and advance the sense of robotic touch in laparoscopic tools in robot-assisted minimally invasive surgery. Haptic feedback from the tooltip and soft tissue surface interaction during robotic palpation can be leveraged to detect the texture and contour of subsurface geometry. However, precise force modulation of the robotic palpating probe is necessary to determine stiff inclusions of the anatomy and maneuver successive manipulation tasks during surgery. This paper focuses on investigating the layered deformations associated with different force profiles involved in manipulating the superficial anatomy of soft tissues during dynamic robotic palpation to determine the underlying anomaly. A realistic three-dimensional (3D) cross-sectional soft tissue phantom with anatomical layers and tumor, as an anomaly, is designed, modeled, and analyzed to examine the effects of oriented palpating forces (0–5 N) of a 7 DOF robot arm equipped with a contoured palpation probe. Finite element static structural analysis of oriented robotic palpation on the developed 3D soft tissue phantoms (with and without anomaly) reveals the soft tissue layer deformations and associated strains needed to identify presence of stiffer inclusions or anomaly during Robotic palpation. The finite element analysis study shows that the difference in deformations of soft tissue layers (e.g., underlying myofascial layers) under stiffer inclusions at different force levels can facilitate haptic feedback to acquire information about subsurface tumors. The deformation variations are further compared to assess better palpation orientations for subsurface anomaly detection.

A narrative review of percutaneous laser disc decompression - early experience in Lagos, Nigeria

Overview. Managing chronic pain arising from the degenerative disc disease of the spine has remained a huge challenge while choosing from within a vast array of treatment armamentarium ranging from the use of medications only or in combination with other physical treatment options, minimally invasive heat therapy, and operative interventions. Patients with chronic pain referred to as ‘contained disc’ in cervical, thoracic, and lumbar disc pathology have been successfully managed with percutaneous laser disc ablative therapy. This approach is only for selected patients and advantages derivable from this approach are the preservation of soft tissue anatomy, minimal post-procedure pain, less metabolic responses, and no blood loss when compared to open surgical procedures. Methodology. This is a one-year retrospective narrative study of six adult patients who presented with chronic low back pain related to the spine and had a lumbosacral spine magnetic resonance imaging (MRI) scan with findings of contained disc herniation. Patients’ brief clinical evaluation which involves biodata, history of pain, and pain scores using the visual analogue scale (VAS) pre and post-intervention and Oswestry disability index to assess disability from chronic pain. A narration of these patient’s progression to follow-up six months after the procedure was documented. Results. The results showed significant improvement in the VAS and ODI scores in five of the 6 patients, with one showing marginal improvement. Conclusion. Percutaneous lumbar disc decompression is effective in the management of chronic low back with concordant clinical and radiological evidence of contained disc pathology.

A Multi-Institutional Analysis of MRI-Based Brachytherapy for Medically Inoperable Endometrial Cancer

Patients with medically inoperable endometrial cancer (MIEC) are curable with brachytherapy (BT)-based treatment yet have competing comorbidities making definitive treatment challenging. MRI demonstrates superior soft tissue anatomy and target volume delineation but with limited data in MIEC patients. We aim to report disease and toxicity outcomes with MRI-based BT and identify dose-volume relationships for toxicities in the treatment of MIEC patients treated with MRI-based BT. We conducted a retrospective multi-institutional analysis of MIEC patients undergoing definitive MRI-based BT (+/- EBRT). MRI-based BT was delivered with the applicator in situ or coregistered to a planning CT. We identified patient, tumor, and dosimetric factors associated with disease and toxicity outcomes. Kaplan-Meier method was used for survival estimates. Log rank test and Cox proportional hazards were used for univariate and multivariate analyses, respectively. T-test was used for dose-volume toxicity analysis. A total of 120 patients were included with a median follow up of 28.0 months. Median age was 68.5 years. ECOG PS was 0-1 in 70%. Clinical stage I was 83.3% and II-IV, 16.7%. Most patients (91.7%) were node negative. Endometrioid and high risk histologies comprised 83.3%, and 16.7%, respectively. EBRT + BT was delivered in 97 patients (80.8%) and BT alone in 23 patients (19.2%). Chemotherapy or hormonal therapy was delivered during treatment in 10 (8.3%) and 11 (9.2%) patients, respectively. Estimated 3-year freedom from local, nodal, and distant recurrence were 88.0%, 96.0%, and 89.1% respectively. Estimated 3-year PFS and OS were 60.9% and 62.9%, respectively. On UVA, older age, PS ≥2, high risk histology, higher grade, and larger GTV at BT were significant (p<0.1). On MVA, older age, higher grade, and larger GTV at BT (p<0.05) predicted for inferior PFS. Fifteen late grade ≥3 toxicities were experienced in 14 (11.6%) patients, 13 of whom received EBRT and BT and 1 who received BT alone. Grade ≥3 toxicities were rectal (2, 1.7%), sigmoid (8, 6.7%), bowel (1, 0.8%), bladder (3, 2.5%), and osseous (1, 0.8%). EBRT was delivered in 7 of 8 sigmoid toxicities. Median sigmoid doses (EQD2a/b = 3Gy) for patients with and without late grade ≥3 sigmoid toxicity were 69.6 Gy and 64.3 Gy, respectively (p = 0.009). MRI-based BT for MIEC patients results in high rates of local control and favorable rates of late grade ≥3 morbidity. Older age, higher grade, and larger GTV at BT predicted for poorer PFS. Sigmoid colon was the predominant organ at risk for grade ≥3 toxicity with a dose -volume relationship observed. Attention to the location of the sigmoid throughout the treatment course may add insight into its predilection for risk. Future work will include additional institutions and dose-volume relationships of target volumes and normal tissues for further disease control and toxicity analysis.