Citations

Background/Objectives: Accurate assessment of spinal bone density is essential for evaluating bone health, particularly in preoperative planning. Conventional manual methods for Hounsfield unit (HU) measurements rely on single-slice measurements within the region of interest, limiting their precision and reproducibility in patients with severe vertebral deformities. We hypothesize that a novel deep-reasoning and learning model (DR-AI) can fully automate spinal bone density assessment volumetrically, with high correlations to spinal bone mineral density (BMD) obtained from dual-energy X-ray absorptiometry (DXA), as well as to the T- and Z-scores. Methods: A cross-sectional study was conducted on patients who had BMD assessment of their lumbar spine and lumbar CT scans within 1 year. The fully-automated DR model was utilized to analyze the soft-tissue window of the lumbar vertebrae CT scans. Spearman correlation coefficients were calculated to assess the strength of relationships between the computed volumetric HUs and the BMD, T-, and Z-scores from each vertebra. Results: 84 patients (67 females, mean age 74.1 ± 10.3 years; 17 males, mean age 68.1 ± 12.4 years) meeting inclusion criteria. Correlation analyses for L1 to L4 showed significant positive relationships (p < 0.0001), with the strongest correlation at L2 between HU and BMD (ρ = 0.75). Conclusions: the DR model for automated assessment of volumetric HUs offers a highly reliable, efficient, and precise alternative to DXA measurements.

Abstract Cadaveric dissections, which are considered the most realistic model to study neuroanatomy, are expensive and not readily available in all centers. Given the surge of technological advances, incorporation of three‐dimensional (3D) scanning technologies and 3D models has gained popularity, both in the educational and clinical settings. We present our institutional experience in creating high‐fidelity neuroanatomical 3D models using three 3D scanning techniques: structured light 3D scanning, “manual” photogrammetry with a single DSLR camera, and “automatic” photogrammetry using a scanner equipped with five vertically arranged DSLR cameras and an automatic turntable within a square box. A survey study was conducted with 20 neurosurgical residents to assess the quality of the three resulting 3D models. In the study, “manual” photogrammetry was determined to be the most cost‐effective technique, while “automatic” photogrammetry was the most time‐effective and user‐friendly technique. The best visual quality was obtained using “manual” photogrammetry, as determined from survey results of 20 neurosurgical residents. While structured light 3D scanning had the lowest quality of resolution of the texture map, this technique was the most accurate to use for determining measurements, with a fixed accuracy of 0.05 mm. Overall, “manual” photogrammetry can allow for the most detailed 3D models and is the most cost‐effective strategy, while structured light 3D scanning is most suitable for obtaining clinically relevant measurements given the high degree of structural accuracy. Alternatively, “automatic” photogrammetry can serve as a hybrid between obtaining relatively high‐quality models in a time‐effective and user‐friendly manner.

Background: Mandible contour significantly influences facial appearance, framing the lower facial silhouette. Redefining mandibular contour is key for facial and neck rejuvenation. Yet, there is limited facial aging research across different lifespans and sexes. Here, we utilize artificial intelligence and advanced 3-dimensional (3D) analysis to elucidate mandibular aging patterns in male and female subjects. Methods: A retrospective analysis of facial computed tomography scans in White patients was conducted, categorizing subjects into 3 age groups (20–79 y) and stratifying them by sex. Artificial intelligence–assisted segmentation into 3D mandibles was done in Mimics v.25, and statistical shape modeling was used to create an average mandible for each group. Volume and linear measurements were assessed via 3D overlays. Results: Analysis of 280 mandibles demonstrated statistically significant aging changes in both sexes. Ramus height showed a marked decrease with age, by approximately 5.3 mm in women and 4.2 mm in men (P < 0.001). Interrami and intercondylar widths increased by a mean of 4–5 mm (P < 0.01). Women exhibited an increase in mandibular angle (P < 0.01), and bony resorption over the chin compared to men, who exhibited concentrated bone resorption at the gonion projection. Conclusions: Mandibular aging, independent of tooth loss, exhibits specific bone remodeling patterns by sex. Posteriorly, mandibular widths increase in both sexes, whereas ramus height decreases. Women experience more resorption at the anterior alveolar surface and chin than men. Statistical shape modeling effectively visualizes these patterns on a population level, bridging the gap between traditional aging research and current understanding.

Background: Despite increased adoption of virtual surgical planning (VSP) in various craniofacial indications, the incorporation of VSP/3DP into facial trauma care remains limited. Therefore, Expedited Preoperative Point of Care for Fracture Reduction to Normalized Anatomy and 3DP to Improve Surgical Outcomes (EPPOCRATIS) was introduced in 2021. This study evaluates our experience with EPPORATIS in craniomaxillofacial trauma over 10 years. Methods: A retrospective review of patients who underwent facial trauma repair between September 2014 and September 2024 was conducted. For each VSP/3DP case, a patient with similar facial trauma patterns, who was treated without VSP, was selected. Evaluation metrics included operative time, blood loss, length of stay, complication rates, and fracture reduction accuracy through 3D heatmap analyses. Operative metrics were normalized by implant (i.e., fracture plates and screws) count to account for fracture complexity. A value of p < 0.05 was deemed statistically significant. Results: The VSP group presented with more complex injuries and higher involvement of various surgical specialties (p < 0.5) and demonstrated longer operative times (p < 0.03). Although the difference was not statistically significant (p = 0.4), when adjusted for implant count, the VSP group had shorter operative times (median: 15.4 vs. 19.3 min/implant) and reduced blood loss compared to non-VSP cases (median: 3.4 mL/implant vs. 4.2 mL/implant). Complications, revision rates, and length of stay showed no significant differences. Conclusions: The use of VSP/3DP (EPPOCRATIS) in craniomaxillofacial trauma reconstruction demonstrated operative efficiency and accurate fracture reduction in complex cases. Further studies are needed to examine the feasibility and cost-effectiveness of point-of-care VSP/3DP in trauma centers.

AbstractPurposeThe small and complex space of the intranasal cavity poses a challenge to teaching and learning sinonasal anatomy in undergraduate medical education. Evidence suggests that utilizing 3D‐printed (3DP) models is an effective means to comprehend anatomical structures and their spatial relationships. In this study, we introduce and evaluate the educational value of rigid nasal endoscopy on realistic 3DP and silicone‐cast sinus models as a method to teach medical students intranasal anatomy.MethodsTwelve first‐year medical students participated in an educational rigid‐nasal endoscopy workshop led by Otolaryngology PGY‐2 residents and rhinology consultants. The workshop consisted of (1) an introductory PowerPoint on rigid nasal endoscopy and basic intranasal anatomy, (2) timed trials that tested students' ability to locate intranasal anatomical structures while scoping with a rigid endoscope, and (3) pre‐ and post‐surveys.ResultsParticipants improved in their ability to locate each intranasal anatomical structure during the timed trials. Participants felt that rigid endoscopy of 3DP models was an effective method to learn intranasal anatomy compared to their traditional medical school anatomy course.ConclusionThe results of this study suggest that rigid nasal endoscopy of 3DP sinus models is a potentially high‐value educational method for teaching intranasal anatomy to first‐year medical students. Students enjoyed the opportunity to learn intranasal anatomy while practicing a clinically relevant procedure ‐ rigid nasal endoscopy.

Objective: The pattern, rate, and natural history of bone flap resorption following cranioplasty with frozen, autologous bone flap has not been fully defined. The authors sought to quantify the progression and natural history of bone flap resorption. Methods: Patients who had craniectomy and delayed cranioplasty with stored, frozen bone flap between 2012 and 2022 were included in this study. Results: Ninety patients (63% male) were included, with a median age of 44.8 years (range: 4.2–84.4 y) at the time of autologous bone flap cranioplasty. Delayed, autologous cranioplasty occurred at a median time of 29.5 days (range: 2 d–10 y) from the index craniectomy. The median follow-up was 16.6 months (range: 3.4–85.4 mo). Radiographically quantifiable bone flap resorption occurred in 50 patients (56%). During the follow-up, the average percentage volume loss was 17%, with a nonlinear pattern of resorption. Following delayed, autologous cranioplasty, 11 patients had clinically significant bone flap resorption requiring secondary alloplastic cranioplasty at a median time of 13.8 months (range: 5.9–57.2 mo), with a mean percentage volume loss of 61%. Younger age was a risk factor for bone flap resorption (P < 0.05), whereas active smoking, presence of comorbidities, and number of days of bone flap storage were not risk factors for bone flap resorption. Penalized B-spline regression analysis showed that bone flap resorption followed a nonlinear pattern. Conclusion: Radiographically quantifiable bone flap resorption occurred in about 56% of patients following delayed autologous cranioplasty. Resorption followed a non-linear pattern. Young age is a risk factor for bone flap resorption.