Adenosine pharmacological stress is commonly used for the detection of ischemia by myocardial perfusion imaging (MPI) using radiotracers and gated single-photon emission computed tomography/computed tomography (SPECT/CT) imaging. Recently, a phenomenon, splenic switch-off (SSO), has been observed where reduced perfusion to the spleen occurs after adenosine, suggesting an adequate effect of adenosine on the heart. The aim of the study is to evaluate the SSO effect in adenosine stress 99mTc tetrofosmin MPI studies using semiquantitative analysis of SPECT/CT data. Seventeen adenosine MPI studies were selected. Each study included stress and rest, which were reoriented in short, horizontal, and vertical long axes. Also, data were reconstructed in the body transaxial, coronal, and sagittal planes. In the resulting images, the spleen was identified on the CT component, and regions of interest were drawn on the spleen, thoracic vertebra, and myocardium. The ratios spleen/vertebra (S/VAd and S/VRst) and myocardium/vertebra (M and M/t) were calculated. Statistical analysis was done using a paired t test. Mean age was 60.35 years, with 9 males (53%). Mean S/VAd was 0.98 ± 0.38 and S/VRst 1.87 ± 0.87 (t = -3.707, P < 0.01). The mean M/VAd was 2.86 ± 1.65 and M/VRst 3.75 ± 2.41 (t = -1.323, P = 0.204). Using the method outlined, especially the S/V ratio, evaluation of the SSO can be achieved from the acquired data, which shows promise as a marker for adequate effectiveness of adenosine stress in doubtful cases.
To investigate the clinical and prognostic relevance of spectral-domain optical coherence tomography (SD-OCT) based novel preoperative staging and postoperative closure pattern classification systems in the management of macular hole (MH). A total 55 patients with idiopathic MH who underwent pars plana vitrectomy with internal limitan peeling surgery were evaluated for minimum linear diameter (MLD), basal hole diameter (BHD), MH edge heights, visual acuity and staging (defines the morphologic outer retinal changes) preoperatively, and postoperative visual acuity and MH closure patterns (MHCPs) (considering the retinal layer reconstitution) in this retrospective study. MLD and BHD values were significantly higher in stage C (606.6 ± 161.1 µm and 1101.6 ± 289.1 µm, respectively, p < 0.05 for each) and stage D (691.5 ± 167.4 µm and 1271.0 ± 119.6 µm, respectively, p < 0.001 for each) than in stage A (381.1 ± 143.8 µm and 578.9 ± 143.3 µm, respectively). Visual acuity scores (postoperative 1st, 3rd and 6th months) were worse in stage C (p < 0.001, p < 0.001 and p = 0.004, respectively) and stage D (p < 0.001for each) compared to stage A, and were better for type 1 A (p < 0.001 for each) and type 1 C (p = 0.010, p < 0.001 and p < 0.001) compared with type 0 closure, and for type 1 A vs. type 1B (p = 0.007 for 3rd month and p = 0.012 for 6th month). Type 0 closure was significantly more common in stage D than in stages A (87.5% vs. 0.0%, p < 0.01 for each) and B (87.5% vs. 13.3%, p < 0.001 for each), while type 1 A closure was more common in stage A (73.3%, p < 0.001) than in stages C (11.8%) and D (0.0%). Our findings revealed clinically relevant associations between novel SD-OCT based preoperative morphological staging and postoperative MHCP classification systems in MH patients, supporting their potential utilization for clinical decision-making and predicting postoperative functional and anatomic prognoses in this setting.
Multiparametric MRI (mpMRI) using the Prostate Imaging Reporting and Data System (PI-RADS v2.1) is widely used for prostate cancer evaluation but is limited by interobserver variability. The PRIMARY score standardizes intraprostatic prostate-specific membrane antigen (PSMA) PET interpretation; however, data using 18F-PSMA-1007, particularly in sub-Saharan Africa, remain limited. To compare the diagnostic performance of 18F-PSMA-1007 PET/computed tomography (CT) and mpMRI and evaluate the association of primary lesion standardized uptake value (SUVmax) and PRIMARY score with adverse clinicopathologic features. This retrospective study included 61 men with biopsy-confirmed prostate cancer who underwent both 18F-PSMA-1007 PET/CT and mpMRI between January 2023 and February 2025. PRIMARY and PI-RADS scores were assigned from PET/CT and mpMRI, respectively. Histopathology served as the reference standard. Sensitivity, positive predictive value (PPV), diagnostic accuracy, and associations between SUVmax and clinicopathologic features were analyzed. PET/CT demonstrated sensitivity of 88.3% and diagnostic accuracy of 86.9%, comparable to mpMRI (86.7 and 85.3%, respectively). Both modalities showed a PPV of 98.1%. SUVmax greater than or equal to 12 was significantly associated with nodal metastases (P = 0.040), distant metastases (P = 0.028), higher Gleason score (P = 0.015), elevated prostate specific antigen (PSA; P = 0.018), seminal vesicle invasion (P = 0.001), and bladder or rectal invasion (P = 0.036). Higher PRIMARY scores also trended toward higher Gleason grade and PSA. 18F-PSMA-1007 PET/CT demonstrated diagnostic performance comparable to mpMRI. SUVmax greater than or equal to 12 (PRIMARY score 5) was associated with aggressive clinicopathologic features, supporting the applicability of the PRIMARY score framework in this sub-Saharan African cohort.
This study aimed to assess the accuracy of intraoral scanning (IOS) for postoperative implant position evaluation in comparison with cone-beam computed tomography (CBCT) across different partially edentulous patterns. We retrospectively analysed 172 patients who underwent implant placement between January 2020 and January 2025. Patients were classified into six clinical subgroups according to edentulous configuration. Nonfree-end patterns were defined as tooth-bounded edentulous spaces with remaining teeth on both sides, whereas free-end patterns lacked a distal tooth-supported reference. IOS- and CBCT-derived postoperative implant positions were compared using shoulder and apical deviations, buccolingual, mesiodistal, and vertical components, and angular deviations. A total of 172 patients with 278 implants were included. The within-group analysis indicated no statistically significant difference between IOS and CBCT measurements in the single tooth and nonfree-end subgroup (Group A). Conversely, the free-end subgroups (Groups B, C, and F) exhibited greater deviations, particularly the unilateral multiple-tooth free-end subgroup (Group C), which demonstrated a significantly different buccal-lingual angular deviation (P < .05). Between-group comparisons confirmed greater discrepancies in free-end than in nonfree-end patterns. Vertical and apical deviations contributed most prominently to subgroup differentiation. The findings from linear discriminant analysis and leave-one-out cross-validation indicated that there was overlap in the deviation performance across edentulous patterns. Nevertheless, vertical displacement, particularly apical deviation, emerged as the most significant indicator for differentiating the characteristic deviations associated with each group. IOS showed better concordance with CBCT in nonfree-end edentulous patterns than in free-end patterns. However, greater variability in free-end cases, particularly in apical and angular measurements, indicates that IOS-based postoperative assessment should be interpreted according to the clinical edentulous pattern. These findings suggest a promising but indication-dependent clinical application of IOS for postoperative implant position assessment.
The goal of this study was to assess the agreement between visual field (VF) and probability maps generated from swept-source optical coherence tomography (SS-OCT) in various stages of glaucoma. This cross-sectional study included patients who underwent VF testing and SS-OCT at the same visit. Patients were classified into early, moderate, and advanced glaucoma according to the Hodapp-Parrish-Anderson criteria. The VF pattern deviation maps were partitioned into 10 defined areas, while the probability maps were divided into 6 defined areas. Areas exhibiting significant defects on the probability map were compared with the corresponding VF defect areas. The agreement between VF and the probability map results was assessed. In early glaucoma, moderate agreement was found between the peripapillary defect on the probability map and the nasal step defect on the VF in both hemifields. As the glaucoma stage progressed, the number of areas showing agreement and the level of agreement between the areas increased. In moderate glaucoma patients, the areas of agreement in both hemifields correspond to the arcuate scotoma pattern. In advanced glaucoma, the probability map and VF showed substantial and almost perfect agreement between many areas corresponding to the ring scotoma pattern. In early, moderate, and advanced glaucoma, a significant agreement was found between the defects on the VF and on the probability map. These findings suggest that probability maps may serve as a promising complementary tool in the assessment of patients with glaucoma and in supporting the evaluation of disease progression, particularly in cases where reliable VFs cannot be obtained.
To determine the reference value of left ventricular (LV) myocardial strain in healthy subjects using cardiac computed tomography feature tracking (CT-FT). This study retrospectively enrolled 128 healthy participants who underwent coronary CT angiography. All participants were free of known cardiovascular diseases and potential cardiovascular risk factors. Global and regional LV strain metrics, including longitudinal strain (LS), circumferential strain (CS), and radial strain (RS), were assessed. The entire cohort included 47 men and 81 women, and the median age was 50.5 (47.0-57.0) years. There was no significant difference of age between females and males (P>0.05). Females demonstrated larger magnitudes of global LS, global CS, and global RS than males (all P<0.05). The LS in the apical slice and CS in the apical slice exhibited the highest magnitudes among the three LV slices. The largest magnitudes of LS and RS were observed in the lateral region, whereas the largest magnitude of CS was demonstrated in the septal region. The gender and LV ejection fraction (LVEF) were associated with global LS and global CS (all P<0.001), whereas only LVEF demonstrated the association with global RS (P<0.001). The global LV myocardial strain demonstrated good measurement reproducibility with intraclass correlation coefficients ranging from 0.836-0.918. The global LV myocardial strain derived from CT-FT in healthy participants is sex-dependent; the LV myocardial strain varies in different levels and regions.
Caregivers may be at risk of exposure to scattered radiation during paediatric chest computed tomography (CT) examinations. This study re-evaluated the effects of physical shielding on paediatric chest CT under controlled experimental conditions using an anthropomorphic paediatric phantom, with an emphasis on the organ dose distribution, scattered radiation relevant to caregivers, and image quality. The phantom was scanned using two CT protocols: with and without bismuth shielding applied to the anterior chest region. Organ doses were measured using real-time scintillation detectors placed in multiple internal organs at the anterior chest surface location corresponding to the breast. Scattered radiation was assessed at caregiver-relevant positions adjacent to the CT gantry using personal dosimeters positioned at the thyroid, eye, abdominal, and gonadal levels. Image quality was evaluated through region-of-interest-based analyses, including the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and Hounsfield unit line profile assessments. The results demonstrated that physical shielding primarily altered the dose distribution in the anterior thoracic regions, including a marked reduction in the breast dose, while doses to the posterior and distant organs were minimally affected. In addition, scattered radiation measurements indicated reduced exposure at caregiver-relevant locations when shielding was applied. Quantitative image analysis showed that shielding-induced changes in the SNR and CNR were measurable but did not compromise the interpretability of the lung parenchyma and other diagnostically relevant regions under controlled conditions. Under these conditions, without automatic exposure control (AEC), physical shielding modified the anterior organ dose distribution and reduced scattered radiation while preserving stable image characteristics. Although the routine clinical use of physical shielding is not advocated, these findings provide quantitative reference data to clarify its potential benefits and limitations in paediatric-specific contexts and support further investigations incorporating AEC and clinical image validation.
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To evaluate if preoperative imaging features from CT at mass-forming intrahepatic cholangiocarcinoma (MF-iCCA) are related to histo-pathologic factors, and to evaluate if those associations can be used to construct an imaging score to predict postoperative recurrence. Consecutive patients with MF-iCCA who underwent preoperative contrast-enhanced CT at two centers between September 2017 and December 2025 were retrospectively reviewed by two radiologists. After independent annotation of 16 imaging features, univariate and multivariate regression analyses were performed to identify independent predictors for high-risk histo-pathologic factors (microvascular invasion, LNM [lymph node metastasis], or poor tumor differentiation). A risk scoring system was developed and used to predict very early recurrence (VER) and early recurrence (ER). In total 152 patients (median age, 62 years [IQR, 54-69 years]; 57 women) were included from two medical centers (training cohort: n = 109; external validation cohort: n = 43). Peritumoral enhancement at arterial phase had the strongest association with high-risk histo-pathologic factors, followed by multinodularity, intrahepatic bile duct dilation, and CT-reported LNM (P < 0.05, all). The four features were used to construct the risk scoring system. Area under the curve (AUC) of VER-weighted and ER-weighted risk scoring system for high-risk histo-pathologic factors was 0.827 and 0.829 in external validation cohort, respectively. The risk scoring system based on high-risk histo-pathologic factors showed superior prognostic performance for VER (AUC, 0.870 [95% CI: 0.761, 0.978]) and ER (AUC, 0.860 [95% CI: 0.737, 0.983]) in external validation cohort. Recurrence of MF-iCCA can be predicted by evaluating preoperative imaging features at CT.
We describe a new genus and species of the small planthopper family Tropiduchidae Stål, 1866, Discotropiduchus junoi gen. et sp. nov. This new taxon highlights the remarkable diversity of tropiduchid planthoppers preserved in Eocene Baltic amber. Moreover, its morphological characters are incompatible with any currently recognized tropiduchid tribe. We therefore discuss the affinities of the new genus with the tribes previously established within Tropiduchidae.
Nasal-type extranodal natural killer/T-cell lymphoma (ENKTL) is a rare malignancy primarily affecting the upper aerodigestive tract. It is strongly associated with Epstein-Barr virus (EBV) infection; thus, EBV-negative cases are extremely rare, and their clinicopathological features and treatment responses are not well defined. A 75-year-old male presented with a persistent skin defect in the medial canthal area of the left eye. He had been treated with antibiotics for presumed cellulitis for 2 months, but the symptoms persisted, and the skin defect worsened. Surgical debridement revealed an irregularly shaped white mass extending into the paranasal sinus. Incisional biopsy revealed atypical lymphocytic infiltration favoring ENKTL. EBV in situ hybridization was negative, supporting the diagnosis of EBV-negative ENKTL. Staging examinations, including whole-body computed tomography and positron emission tomography, revealed localized disease involving only the orbit and paranasal sinuses. The patient was treated with etoposide, ifosfamide, cisplatin, and dexamethasone chemotherapy. After the first cycle, the patient developed severe neutropenia, and the chemotherapy dose was reduced by 40% for the second cycle. After 2 cycles of etoposide, ifosfamide, cisplatin, and dexamethasone chemotherapy, consolidation radiation therapy was recommended. After 2 cycles of chemotherapy, positron emission tomography showed metabolic complete remission. At 3 months after the second cycle of chemotherapy, the skin defect had completely healed, and follow-up computed tomography showed disease remission. Cutaneous manifestations of ENKTL can mimic benign inflammatory conditions such as cellulitis, leading to delayed diagnosis. Clinicians should maintain a high index of suspicion and perform early tissue biopsy for atypical ulcerative lesions in the periorbital and nasal areas, even in the absence of typical EBV positivity.
Traumatic stapediovestibular luxation is a rare but potentially devastating condition that may cause severe vertigo and hearing loss. Optimal management remains controversial because surgical manipulation around the stapes carries the risk of additional inner ear damage, whereas some patients recover with conservative treatment alone. Two patients presented with vertigo and hearing impairment after accidental penetrating ear trauma caused by cotton swabs. High-resolution computed tomography demonstrated stapes footplate invagination into the vestibule in both cases. In Case 1, early surgical repositioning of the stapes was performed on the third day after injury because of complete footplate invagination accompanied by bone-conduction hearing loss and severe vertigo. In Case 2, conservative management was selected because bone-conduction thresholds were preserved and vestibular symptoms improved spontaneously. In Case 1, postoperative recovery included rapid resolution of vertigo and improvement of bone-conduction thresholds, particularly at low frequencies. In Case 2, vestibular symptoms resolved without surgery, although a mild residual air-bone gap remained. Bone-conduction deterioration, degree of footplate displacement, severity of vertigo, and depth of invagination on high-resolution computed tomography appear to be key factors for treatment selection. Conservative management may be safely continued in selected cases with mild posterior partial luxation and stable bone-conduction, whereas early surgical decision-making is essential when surgery is indicated to optimize vestibular and auditory outcomes.
The prognostic value of interim 18F-fluorodeoxyglucose positron emission tomography/computed tomography (iPET/CT) in diffuse large B-cell lymphoma (DLBCL) remains a subject of debate due to inconsistencies in timing and interpretation. This updated systematic review and meta-analysis aimed to investigate the ability of iPET to predict progression-free survival (PFS). A systematic literature search was conducted across PubMed/MEDLINE, Cochrane, and Embase databases until December 31, 2025. Studies investigating the prognostic value of iPET/CT for PFS in DLBCL were included. Data on complete metabolic response (CMR) rates and hazard ratios (HR) for PFS were pooled using a random-effects model. The pooled CMR rate across 66 articles (9.335 patients) was 67.2% (95% confidence interval [CI]. 63.9%-70.4%), though significant variability (38%-94%) and extreme heterogeneity were observed (I2 = 92.45%). Subgroup analysis confirmed that timing influenced these rates: CMR was 63.3% after 2 cycles vs. 74.4% after 4 cycles. Regarding PFS, the pooled HR across 63 studies was 3.05 (95% CI, 2.63-3.54) for a positive iPET. Notably, utilizing a Deauville score (DS) threshold of 5 alone yielded a significantly higher pooled HR of 5.72 (95% CI, 4.35-7.51) with more moderate heterogeneity (I2 = 40.7%). In contrast, the prognostic effect of ΔSUV66% was weaker, with a pooled HR of 1.83. Scans performed after 4 cycles (iPET4, HR: 3.20) showed slightly stronger prognostic performance than those after 2 cycles (iPET2, HR: 2.84). Interim PET/CT, particularly when utilizing the DS 5 threshold, is a strong biomarker for identifying high-risk DLBCL patients.
Cardiovascular diseases (CVDs) remain among the leading causes of both health and economic burdens worldwide. Myocardial Perfusion Imaging (MPI) performed using Single Photon Emission Computed Tomography (SPECT) or, more recently, Positron Emission Tomography (PET), has long served as a cornerstone in the diagnosis and management of coronary heart disease (CHD). However, rising healthcare costs and rapidly advancing imaging technologies have prompted re-evaluation of nuclear cardiology's cost-effectiveness, making careful selection of imaging modalities essential. In this review, an economic evaluation of imaging in CHD has been undertaken, summarizing the most relevant studies on the cost-effectiveness of various imaging modalities. The heterogeneity in data - largely related to institutional resources, operator expertise, clinical setting (inpatient vs. outpatient), healthcare system, and reimbursement structure - does not yet allow definitive conclusions on the cost-effectiveness of each individual modality. Therefore, a well-structured multimodality imaging approach appears to provide greater diagnostic and economic value, offering both improved clinical outcomes and more efficient resource utilization.
Primary Cutaneous Anaplastic Large Cell Lymphoma (PCALCL) is a CD30-positive T-cell lymphoma that typically manifests as a dermal nodule or tumor with favorable prognosis. Rare morphologic variants with prominent myxoid stroma can closely mimic myxoid soft tissue sarcomas and lead to misdiagnosis. A 40-year-old man presented with a slowly enlarging ulcerated mass on the left thigh that was radiologically regarded as a superficial soft tissue sarcoma, prompting wide excision with sentinel lymph node biopsy. Histological examination showed a multinodular, dermal, and subcutaneous tumor composed of highly pleomorphic hallmark-type, rhabdoid, epithelioid, and spindle cells, along with multinucleated forms embedded in abundant myxoid stroma, and associated with delicate curvilinear vessels. Immunohistochemically, all tumor cells demonstrated strong and diffuse CD30, CD2, and CD4 expression; and weak positivity for EMA. They were negative for CD3, CD5, CD7, CD8, TIA-1, and perforin, and also showed no expression of ALK or of epithelial, melanocytic, myogenic, vascular, or B-cell markers. These findings support the diagnosis of ALK-negative myxoid PCALCL. Comprehensive staging with positron emission tomography-computed tomography and bone marrow biopsy revealed no extracutaneous disease, and the patient achieved a complete metabolic remission after 6 cycles of CHOP-E chemotherapy, remaining disease-free for 40 months after diagnosis. This case broadens the clinicopathologic spectrum of PCALCL and highlights that infiltrative and myxoid CD30-positive tumors of the extremities may masquerade as sarcoma, underscoring the importance of including CD30 and T-cell markers in the evaluation of pleomorphic myxoid soft tissue tumors.
This study aimed to evaluate the accuracy and clinical utility of a novel, non-invasive cone-beam computed tomography (CBCT)-based protocol for measuring gingival thickness in the maxillary anterior region, using transgingival probing (TGP) as the reference standard. In this cross-sectional study, 39 periodontally healthy patients (24 males, 15 females; mean age 36 ± 12 years) were recruited. Gingival thickness was measured at 2 mm, 4 mm, and 6 mm apical to the gingival zenith on the facial aspect of maxillary anterior teeth (234 teeth, 702 sites) using both TGP and a CBCT protocol involving radiopaque resin markers. Method agreement was analyzed via Bland-Altman plots and Deming regression. Diagnostic performance of CBCT for classifying gingival phenotype was assessed. CBCT measurements showed a strong correlation with TGP (ρ > 0.98, p < 0.001). Deming regression indicated a constant systemic error, with CBCT underestimating thickness by approximately 0.04 mm (95% CI: -0.053 to -0.035), but no proportional error. Despite this minor bias, agreement was excellent (Kappa > 0.95). CBCT demonstrated 100% specificity and > 96% sensitivity for identifying thick phenotypes. No significant differences in gingival thickness were found between genders. The novel CBCT-based measurement protocol shows high agreement with gold standard. The identified constant error is clinically negligible, supporting its utility as a reliable, non-invasive method for assessing gingival thickness and phenotype, with potential for integration with digital impression technology.
Conduction system pacing (CSP) remains technically challenging because intentional targeting of proximal conduction structures such as the distal His bundle and proximal left bundle branch (LBB) trunk is difficult using current implantation techniques. We evaluated a novel computed tomography angiography (CTA)-guided workflow designed to facilitate patient-specific targeting of these structures. Conduction Guided Intervention (CGI) integrates pre-procedural cardiac CTA with patient-specific conduction system reconstruction and real-time fluoroscopic overlay. In this first-in-human prospective study, 40 consecutive patients undergoing CSP were enrolled. Procedural success was defined as implantation at a proximal conduction system target according to predefined anatomical and electrophysiological criteria. Clinical success required proximal conduction system capture with QRS correction at working output. Procedural success was achieved in 38/40 patients (95%). CTA analysis demonstrated substantial inter-individual variability in proximal conduction system anatomy, with marked differences in distances and trajectories along the AVN-His axis between patients. Distal His pacing according to predefined procedural criteria was initially achieved in 26 patients (65%). However, transition to proximal LBB trunk pacing was required in 12 patients because of inadequate QRS correction and/or unfavorable pacing thresholds. Final adjudicated pacing sites included distal His pacing in 14 patients (35%) and proximal LBB trunk pacing in 22 patients (55%), resulting in proximal conduction system pacing in 36/40 patients (clinical success 90%). CTA-guided conduction system mapping was feasible and enabled intentional targeting of proximal conduction structures in most patients. Integration of patient-specific anatomical information may complement conventional fluoroscopic and electrophysiological guidance during CSP implantation.
The epidemiology and characteristics of shoulder dislocations in the context of epileptic seizures, as well as treatment recommendations, have so far been not described in detail in the literature. The aim of this retrospective study is to document the epidemiological characteristics and treatment options of shoulder instabilities occurring during epileptic seizures, as well as to quantify associated injuries. As part of a retrospective analysis, 72 shoulders in 56 patients at our clinic were evaluated who sustained shoulder dislocation during an epileptic seizure. An analysis of the epidemiology and key characteristics was conducted. Sectional imaging including computer tomography scans and/or magnetic resonance imaging of all patients were independently analyzed at different time points by two raters (A.P. and H.G.) using OsiriX™ (Geneva, Switzerland) for glenoid defects as well as the Hill-Sachs lesion (HSL) and the reverse HSL (RHSL). When present, surgical treatment modalities were analyzed. The cohort had a mean age of 37 ± 16 years; 12 were female (21%) and 44 were male (79%). A total of 72 shoulder dislocations were identified: 60% anterior (43/72), 30% posterior (22/72), and 10% bidirectional (7/72); 51% were first-time dislocations (37/72) and 49% recurrent (35/72). Radiological imaging suitable for quantitative defect analysis was available for 47 shoulders, including 30 anterior and 17 posterior dislocations. The anterior glenoid defect size of patients with anterior dislocation averaged 11% (± 8%) and the mean posterior glenoid defect size of patients with posterior dislocation was 7% (± 6%). 16 of the 30 anterior dislocations and three of the 17 posterior shoulder dislocations were recurrent. Significant differences between first-time and recurrent dislocations were found in HSL width (13 mm vs. 15 mm; p = 0.008), HSL length (24 mm vs. 29 mm; p < 0.001), posterior glenoid defect size (5% vs. 13%; p = 0.04), and reverse HSL γ-angle (114° vs. 84°; p = 0.003). Fractures occurred in 46.4% of patients (26/56), all involving the proximal humerus, three patients also sustained a glenoid fracture. 62.5% of injuries were treated surgically (45/72). Surgical techniques included soft tissue stabilization (26.7%; 12/45), bony augmentation (24.4%; 11/45), arthroplasty (4.4%; 2/45), and humeral open reduction and internal fixation (44.4%; 20/45). In patients with epilepsy, shoulder dislocations predominantly occur during generalized seizures, with anteroinferior dislocations being the most frequent, while posterior dislocations are significantly more prevalent compared to the general population. Recurrent dislocations were associated with significantly larger humeral and posterior glenoid defects, indicating progressive bone loss. Approximately half of all injuries involved proximal humerus fractures, with more than half requiring surgical intervention. IV.
This finite element analysis study aimed to compare the biomechanical performance of implants made from polyetheretherketone (PEEK), 30% short carbon fiber-reinforced PEEK (30% SCFR-PEEK), 60% continuous carbon fiber-reinforced PEEK (60% CCFR-PEEK), and titanium in a full-arch fixed implant restoration for the edentulous maxilla. A three-dimensional finite element model of an edentulous maxilla was constructed from Cone-Beam Computed Tomography (CBCT) data. The bone was modeled with a 2 mm cortical layer surrounding a cancellous core. Four implants supporting a full-arch prosthesis were simulated. Implants materials were assigned properties from literature (PEEK: 4.1 GPa; 30% SCFR-PEEK: 18 GPa; 60% CCFR-PEEK: 150 GPa; titanium: 110 GPa). Three occlusal loading conditions (centric, lateral, protrusive) were applied. The maximum von Mises stress values and stress distribution in the implants, cortical bone, and cancellous bone was analyzed. Implant stress was highest in 60% CCFR-PEEK, followed by titanium, 30% SCFR-PEEK, and PEEK. Cortical bone stress was lowest around stiff implants (60% CCFR-PEEK, titanium) and highest around PEEK and 30% SCFR-PEEK. The 30% SCFR-PEEK group showed the smallest implant-bone stress gradient and the most uniform stress distribution. The 30% SCFR-PEEK implant exhibited superior biomechanical compatibility for maxillary complete-arch rehabilitation. Its intermediate stiffness promoted physiological stress transfer to peri-implant bone.