Evaluation of MRI-based radiomic features in heart morphologic variations as a consequence of autoimmune thyroid disorders.

Radiomics (RC) was initially developed using computed tomography (CT) for oncological imaging. However, it can be applied to various scientific and clinical radiology fields regardless of the modalities involved. The purpose of this survey was to evaluate alterations in magnetic resonance imaging of the heart (CMR) in patients suffering from autoimmune thyroid disorders (AITD) by applying RC tools and mapping features. A total of 50 individuals were evaluated in this study. We searched for CMR examinations performed in our department between January 2019 and 2021 in patients with AITD. Thirty patients with AITD (21 men and 9 women, aged 51 to 78 years; mean age, 60 years) were enrolled in our survey. We enrolled a control group (CG) of 20 individuals (14 men and 6 women aged 53-87 years; mean age, 68 years) without AITD or cardiac disorders. Global native T1 and T2 mapping revealed no significant differences between groups. However, we identified significantly higher values of several texture parameters, including the gray-level co-occurrence matrix (GLCM) entropy, gray-level run-length matrix (GLRLM; short-run high gray-level emphasis (SRHGE), GLCM (Energy), gray-level size zone matrix length matrix (GLZLM; LZLGE), GLZLM (SZLGE), DISCRETIZED (HISTO-Energy) GLCM (Dissimilarity), and GLCM (Contrast), in patients with AITD in comparison to the CG (P < .01). Our results indicate that several RC properties extracted from CMR images can be used to discriminate between the AITD and CG groups.

Biomechanical evaluation of the proximal chevron osteotomy in comparison to the Lapidus arthrodesis for the correction of hallux valgus deformities.

PURPOSE: The proximal chevron osteotomy and the modified Lapidus arthrodesis are both procedures utilized for deformity correction in patients with severe symptomatic hallux valgus. The aim of the current study was to compare their biomechanical stability when using locking plate fixation. METHODS: Twelve matched pairs of human anatomical lower leg specimens underwent on one side a proximal chevron osteotomy with a medial locking plate and on the other side a modified Lapidus arthrodesis with a plantar locking plate utilizing an interfragmentary compression screw. All specimens underwent bone mineral density (BMD) assessment and were tested in a servohydraulic load frame which applied a load on the centre of the metatarsal head over 1000 loading cycles with subsequently ultimate load testing. Displacement of the proximal and distal bone segment, ultimate load, and bending stiffness were analyzed. RESULTS: Mean displacement of both procedures showed no statistically significant difference throughout all the loading cycles (0.213 ≤ p ≤ 0.834). The mean ultimate load of the proximal chevron osteotomy was 227.9 N (± 232.4) and of the modified Lapidus arthrodesis 162.9 N (± 74.6) (p = 0.754). The proximal chevron osteotomy (38.2 N/mm (± 24.9)) had a significantly higher bending stiffness compared to the modified Lapidus arthrodesis (17.3 N/mm (± 9.9)) (p = 0.009). There was no correlation between BMD and displacement in all loading cycles, ultimate load, and bending stiffness of either procedure (p > 0.05). CONCLUSION: Although the bending stiffness of the chevron osteotomy was higher, there was no statistically significant difference between the surgical techniques in mean displacement and ultimate load. The BMD did not influence the overall stability of either reconstruction. Locking plate fixation increases the clinical value of the modified Lapidus arthrodesis by outweighing most of the biomechanical disadvantages in comparison to the proximal chevron osteotomy.

Single-Center Comparison of [64Cu]-DOTAGA-PSMA and [18F]-PSMA PET-CT for Imaging Prostate Cancer.

INTRODUCTION: the diagnostic performance of [64Cu]-DOTAGA-PSMA PET-CT imaging was compared retrospectively to [18F]-PSMA PET-CT in prostate cancer patients with recurrent disease and in the primary staging of selected patients with advanced local and possible metastatic disease. METHODS: We retrospectively selected a total of 100 patients, who were consecutively examined in our department, with biochemical recurrence after radical prostatectomy or who had progressive local and possible metastatic disease in the last 3 months prior to this investigation. All patients were examined with a dedicated PET-CT scanner (Biograph; Siemens Healthineers). A total of 250 MBq (3.5 MBq per kg bodyweight, range 230-290 MBq) of [64Cu]-DOTAGA-PSMA or [18-F]-PSMA was applied intravenously. PET images were performed 1 h post-injection (skull base to mid-thigh). The maximum standardized uptake values (SUVmax) of PSMA-positive lesions and the mean standardized uptake value (SUVmean) of the right liver lobe were measured. RESULTS: All but 9/50 of the patients (18%; PSA range: 0.01-0.7 µg/L) studied with [64Cu]-DOTAGA-PSMA and 6/50 of the ones (12%; PSA range: 0.01-4.2) studied with [18F]-PSMA had at least one positive PSMA lesion shown by PET-CT. The total number of lesions was higher with [64Cu]-DOTAGA-PSMA (209 vs. 191); however, the median number of lesions was one for [64Cu]-DOTAGA-PSMA and two for [18F]-PSMA. Interestingly, the median SUVmean of the right liver lobe was slightly higher for [18F]-PSMA (11.8 vs. 8.9). CONCLUSIONS: [64Cu]-DOTAGA-PSMA and [18F]-PSMA have comparable detection rates for the assessment of residual disease in patients with recurrent or primary progressive prostate cancer. The uptake in the liver is moderately different, and therefore at least the SUVs of the lesions in both studies would not be comparable.

Analysis of bone architecture using fractal-based TX-Analyzer™ in adult patients with osteogenesis imperfecta.

BACKGROUND: Osteogenesis imperfecta (OI) is a rare genetic disorder characterized by impaired bone quality and quantity. Established imaging techniques have limited reliability in OI. The TX-Analyzer™ is a new, fractal-based software allowing a non-invasive assessment of bone structure based on conventional radiographs. We explored whether the TX-Analyzer™ can discriminate OI patients and healthy controls. Furthermore, we investigated the correlation between TX-Analyzer™ parameters and (i) bone mineral density (BMD) by Dual Energy X-ray Absorptiometry (DXA), (ii) trabecular bone score (TBS), and (iii) bone microstructure by high-resolution peripheral quantitative computed tomography (HR-pQCT). MATERIAL AND METHODS: Data of 29 adult OI patients were retrospectively analyzed. Standard radiographs of the thoracic and lumbar spine were evaluated using the TX-Analyzer™. Bone Structure Value (BSV), Bone Variance Value (BVV), and Bone Entropy Value (BEV) were measured at the vertebral bodies T7 to L5. Data were compared to a healthy, age- and gender-matched control group (n = 58). BMD by DXA, TBS, and trabecular bone microstructure by means of HR-pQCT were correlated to TX-Analyzer™ parameters in OI patients. The accuracy of the TX-Analyzer™ parameters in detecting OI was assessed with area under curve (AUC) analysis of receiver operating characteristic (ROC). RESULTS: BEV of the thoracic and the lumbar spine were significantly lower in OI patients compared to controls (both p < 0.001). BEV of the thoracic spine was significantly correlated to TBS (ρ = 0.427, p = 0.042) as well as trabecular number (Tb.N) at the radius (ρ = 0.603, p = 0.029) and inhomogeneity of the trabecular network (Tb.1/N.SD) at the radius (ρ = -0.610, p = 0.027), when assessed by HR-pQCT. No correlations were found between BEV and BMD by DXA. BEV of the thoracic and the lumbar spine had an AUC of 0.81 (95% confidence interval [CI] 0.67-0.94, p < 0.001) and 0.73 (95% CI 0.56-0.89, p = 0.008), respectively. BSV and BVV did not differ between OI patients and controls. CONCLUSION: The software TX-Analyzer™ is able to discriminate patients with OI from healthy controls. ROC curves of BEV values suggest a suitable clinical applicability. Low to no correlations with conventional methods suggest, that the TX-Analyzer™ may indicate a new and independent examination tool in OI.

Theranostics of Metastatic Prostate Cancer Applying 64Cu/18F/68Ga PSMA PET-CT and 177Lu Radiopharmaceuticals.

The successful use of theranostic twins in neuroendocrine tumors (NET) is the pioneering approach to radionuclide therapy in other tumor types. 64Cu/18F PSMA for molecular imaging with PET-CT and peptide radioligand therapy (PRLT) with 177Lu labeled PSMA inhibitors are the next theranostic twins in nuclear medicine. 68Ga/ 64Cu/18F PSMA PET-CT detects metastatic prostate cancer with high diagnostic sensitivity and specificity and can be used to select patients for PRLT and evaluate therapy response. Radionuclide therapy with 177Lu-PSMA inhibitors has been shown to be effective in the treatment of metastatic CRPC.

64Cu-DOTATOC PET-CT in Patients with Neuroendocrine Tumors.

INTRODUCTION: Several radiolabeled somatostatin analogues have been developed for molecular imaging of neuroendocrine tumors (NETs) with single-photon emission computed tomography (SPECT) and positron-emission tomography (PET). The aim of the present study was to report our first results using 64Cu-DOTATOC in patients with NETs. METHODS: Thirty-three patients with NETs (15 female, 18 male; mean age 64 ± 13 years) were included in this retrospective study. 64Cu-DOTATOC PET-CT scans were performed on all patients. RESULTS: Five out of 33 patients with a history of NET after surgical removal of the primary lesion showed no pathological lesions on PET-CT imaging and 8/33 patients had enhanced uptake in the area of recurrent meningioma at the skull base. The remaining 20/33 patients had a history of neuroendocrine tumor in the gastrointestinal tract (GEP-NET) and were presented with at least one pathological lesion. CONCLUSION: The high detection rate of suspected lesions in patients with NETs and the high target-to-background contrast found in this study hold promise for the safe application of 64Cu-DOTATOC in patients with NET.

Peroneus brevis as source of instability in Jones fracture fixation.

PURPOSE: Intramedullary screw fixation is currently considered the gold standard treatment for Jones fractures in the athlete. Besides biological factors (i.e., poor vascularization), mechanical instability induced by the pull of the peroneus brevis tendon (PBT) contributes to deficient Jones fracture healing. This biomechanical study aimed to simulate loads induced by the PBT at the fifth metatarsal and to compare the stability of two intramedullary screw constructs in a Jones fracture fixation model. METHODS: Jones fractures were created in 24 human paired specimens, and fixation was achieved with either a solid Jones fracture specific screw (JFXS) (Jones Screw; Arthrex Inc., Naples FL, USA) or a cannulated headless compression screw (HCS) (HCS; DePuySynthes, Solothurn, Switzerland). The PBT was fixed to a mechanical load frame by the use of a cryoclamp. Constructs were loaded in tension for 1000 cycles, followed by an ultimate load test. Construct failure was defined by exceeding 10° of dorsal angulation. RESULTS: Preliminary failure occurred more often in HCS constructs (33%) compared to JFXS constructs (0%) (P = 0.044). Mean tensile load to failure reached 123.8 ± 91.4 N in the JFXS group and 91.5 ± 62.2 N in the HCS group (P = 0.337). The mean slope of the load-displacement curve was 24.2 ± 10.4 N/mm for JFXS constructs and 24.7 ± 5.5 N/mm for HCS constructs, respectively (P = 0.887). CONCLUSION: This is the first study evaluating the effect of PBT pull on the mechanical stability of Jones fracture fixation. Higher preliminary failure rates of HCS were found under cyclic loading conditions compared to JFXS.

Fractal-Based Analysis of Bone Microstructure in Crohn's Disease: A Pilot Study.

Crohn's disease (CD) is associated with bone loss and increased fracture risk. TX-Analyzer™ is a new fractal-based technique to evaluate bone microarchitecture based on conventional radiographs. The aim of the present study was to evaluate the TX-Analyzer™ of the thoracic and lumbar spine in CD patients and healthy controls (CO) and to correlate the parameters to standard imaging techniques. 39 CD patients and 39 age- and sex-matched CO were analyzed. Demographic parameters were comparable between CD and CO. Bone structure value (BSV), bone variance value (BVV) and bone entropy value (BEV) were measured at the vertebral bodies of T7 to L4 out of lateral radiographs. Bone mineral density (BMD) and trabecular bone score (TBS) by dual energy X-ray absorptiometry (DXA) were compared to TX parameters. BSV and BVV of the thoracic spine of CD were higher compared to controls, with no difference in BEV. Patients were further divided into subgroups according to the presence of a history of glucocorticoid treatment, disease duration > 15 years and bowel resection. BEV was significantly lower in CD patients with these prevalent risk factors, with no differences in BMD at all sites. Additionally, TBS was reduced in patients with a history of glucocorticoid treatment. Despite a not severely pronounced bone loss in this population, impaired bone quality in CD patients with well-known risk factors for systemic bone loss was assessed by TX-Analyzer™.

Evaluation of Two Types of Intramedullary Jones Fracture Fixation in a Cyclic and Ultimate Load Model.

Implant choice is a matter of concern in athletes and active patients who sustain a Jones fracture because they are prone to failure including non-union, screw failure, and refracture. The aim of this study was to compare the biomechanical behavior of a Jones fracture-specific screw (JFXS) with a cannulated headless compression screw (HCS) in a simulated partial weight-bearing and ultimate load Jones fracture fixation model. Ten matched pairs of human anatomical specimens underwent Jones fracture creation and consecutive intramedullary stabilization with a solid JFXS or a cannulated HCS. The bone mineral density was assessed prior to testing. Cyclic plantar to dorsal loading was applied for 1000 cycles, followed by load to failure testing. Angulation was measured by an opto-electronic motion capture system and mode of failure classification was determined by video analysis. Paired analysis showed no statistically significant difference between both screw constructs. Ultimate load reached 236.9 ± 107.8 N in the JFXS group compared with 210.8 ± 150.7 N in the HCS group (p = 0.429). The bone mineral density correlated positive with the pooled ultimate load (R = 0.580, p = 0.007) for all constructs and negatively with angulation (R = -0.680, p = 0.002) throughout cyclic loading. Solid fracture-specific and cannulated headless compression screws provide equal ultimate loads and stiffness for Jones fracture fixation. A low bone mineral density significantly impairs the construct stability and the ultimate load of both intramedullary screw constructs. © 2019 The Authors. Journal of Orthopaedic Research ® published by Wiley Periodicals, Inc. on behalf of Orthopaedic Research Society J Orthop Res 38:911-917, 2020.

[Reduced Caliber of the Ophthalmic Artery in Magnetic Resonance Angiography in Patients after Retinal Artery Occlusion]. / Kaliberreduktion der A. ophthalmica in der Magnetresonanzangiografie bei Patienten nach retinalen arteriellen Verschlüssen.

BACKGROUND: Retinal artery occlusion (RAO) is caused by embolic occlusion of retinal arteries. Previous strokes in the medical history were reported in up to 20% of patients. According to data from a computational blood flow analysis based on magnetic resonance imaging of a patient with RAO, about 90% of ascending emboli are washed into the brain, leaving speculations about further embolic sources for RAO, such as plaques or stenosis of the ophthalmic artery. The aim of this study was to examine the reduced caliber of the ophthalmic artery in magnetic resonance angiography (MRA). PATIENTS AND METHODS: An analysis of a prospective case series of 9 patients with newly diagnosed RAO, presenting at the outpatient department. Magnetic resonance angiography of the brain, including the ophthalmic artery and carotid siphon was performed in all patients and evaluated by an experienced radiologist also specialised in neuroradiology. Outcomes were compared to an age-matched control group of 9 patients without RAO. RESULTS: Four of 9 patients (44.4%) had a reduced caliber of the ophthalmic artery, two only at the side of RAO and another two bilateral. One of these cases also had a severe steno-occlusive disease of the internal carotid artery in the MRA, being in accordance with the results from duplex-sonography of the internal carotid artery. None of the patients in the control group had any signs of stenosis of the ophthalmic artery. CONCLUSIONS: Reduced caliber of the ophthalmic artery in MRA is present in almost half of patients with RAO and indicates that steno-occlusive disease of the ophthalmic artery could be a possible source of emboli, causing RAO.

Bone Scintigraphy in Staging of Newly Diagnosed Prostate Cancer in Regard of Different Risk Groups.

OBJECTIVES: Prostate cancer (PC) is the most common cancer in men over 50 years of age. Bone scintigraphy is still performed in many institutions at the time of primary diagnosis. We aimed to evaluate the role of bone scan in the primary staging of PC in regard of different risk groups. METHODS: A retrospective analysis of bone scans in 296 patients (mean age 64±6 y) acquired at the time of primary diagnosis was performed in our institution. The median prostate specific antigen (PSA) was 6.73 ng/ml, all patients had a Gleason score of >5. RESULTS: Only 11/296 patients had a positive bone scan, 1 being in the intermediate risk group, 10 in the high-risk group and none in the low-risk group according to D'Amico classification. CONCLUSION: Our results support the few published studies that less than 10% of patients with newly diagnosed PC by biopsy would develop bone metastasis, all in the intermediate or high-risk groups. Therefore, a staging by bone scan can only be recommended in patients with intermediate or high-risk, or symptomatic patients only.

Biomechanical evaluation of different ankle orthoses in a simulated lateral ankle sprain in two different modes.

Ankle orthoses are commonly used for prevention of recurrent ankle sprains. While there are some data on their functional performance or restriction of range of motion, there is little knowledge on the quantifiable passive mechanical effectiveness of various devices. This study aimed to determine the prophylactic stabilization effect for commonly prescribed ankle orthoses in a simulated recurrent ankle sprain. Eleven anatomic lower leg specimens were tested in plantar flexion and hindfoot inversion in a simulated ankle sprain in a quasi-static and dynamic test mode at 0.5°/s and 50°/s internal rotation, respectively. Tests included intact specimens, same specimens with the ruptured anterior talofibular ligament (ATFL), followed by stabilization with five different semi-rigid orthoses: AirGo Ankle Brace, Air Stirrup Ankle Brace, Dyna Ankle 50S1, MalleoLoc, and Aequi. Compared to the injured and unprotected state, two orthoses (AirGo and Air Stirrup) significantly reinforced the ankle. The Aequi ankle brace restored stability comparable to an intact joint. Dyna Ankle 50S1 and MalleoLoc provided insufficient resistance to applied internal rotation compared to the ankle with ruptured ATFL. Ankle orthoses varied significantly in their ability to stabilize the unstable ankle during an ankle sprain in both testing modes. Presented objective data on passive stabilization reveal a lack of supporting evidence for clinical application of ankle orthoses.

[The role of molecular imaging (PET-CT) in the diagnostic and treatment pf prostate cancer]. / Die Rolle der molekularen Bildgebung (PET-CT) in der Diagnostik und Therapie des Prostatakarzinoms.

Prostate cancer is the most frequent cancer type in men in industrialized countries. In case of biochemical recurrent disease of prostate cancer is molecular imaging with PET-CT or PET-MRI a very promising modality for the detection of local recurrence, lymph node involvement or distant metastasis. Of the so far implemented radiopharmaceuticals the radioactive labeled PSMA ligands (i. e. Ga-68 PSMA) have prevailed. There are also in the meanwhile treatment approaches with PSMA ligands (i. e. Lu-177 PSMA) in case of metastatic disease.

Bone matrix hypermineralization associated with low bone turnover in a case of Nasu-Hakola disease.

Analysis of tissue from a 34-years-old male patient from Austrian origin with a history of multiple fractures associated with painful episodes over the carpal, tarsal and at the end of the long bones respectively is presented. Radiographic images and axial 3DCT scans showed widespread defects in trabecular bone architecture and ill-defined cortices over these skeletal sites in the form of discrete cystic-like lesions. Family history indicated two sisters (one half and one full biological sisters) also with a history of fractures. Whole exome sequencing revealed two heterozygous missense mutations in TYROBP (MIM 604142; NM_003332.3) gene encoding for a cell-surface adaptor protein, which is part of a signaling complex triggering activation of immune responses. It is expressed in cells of the ectoderm cell linage such as NK and dendritic cells, macrophages, monocytes, myeloid cells, microglia cells and osteoclasts. The phenotype and genotype of the patient were consistent with the diagnosis of Nasu-Hakola disease (NHD) (OMIM 221770). Investigations at the bone material level of a transiliac bone biopsy sample from the patient using polarized light microscopy and backscatter electron imaging revealed disordered lamellar collagen fibril arrangement and extensively increased matrix mineralization. These findings are the first bone material data in a patient with NHD and point toward an osteoclast defect involvement in this genetic condition.