Coronal plane in opportunistic screening of osteoporosis using computed tomography: comparison with axial and sagittal planes

OBJECTIVE

To compare the coronal plane with axial and sagittal planes in opportunistic screening of osteoporosis using computed tomography (CT).

MATERIALS AND METHODS

A total of 100 patients aged ≥ 50 years who underwent both lumbar spine CT and dual-energy X-ray absorptiometry within 3 months were included. Osteoporosis was diagnosed based on dual-energy X-ray absorptiometry results. The CT number was measured at the center of the vertebral body in coronal, axial, and sagittal planes. To compare the coronal plane with axial and sagittal planes in diagnosing osteoporosis, the areas under the receiver operating characteristic curve (AUC) were compared and intraclass correlation coefficient (ICC) was calculated. The optimal cutoff values were calculated using Youden's index.

RESULTS

The AUC of the coronal plane (0.80; 95% confidence interval [CI], 0.71-0.89) was not significantly different from that of the axial plane (0.78; 95% CI, 0.68-0.87; P = 0.39) and that of the sagittal plane (0.78; 95% CI, 0.69-0.87; P = 0.68). Excellent concordance rates were observed between coronal and axial planes with ICC of 0.95 (95% CI, 0.92-0.96) and between coronal and sagittal planes with ICC of 0.93 (95% CI, 0.85-0.96). The optimal cutoff values for the coronal, axial, and sagittal planes were 110, 112, and 112 HU, respectively.

CONCLUSION

The coronal plane does not significantly differ from axial and sagittal planes in opportunistic screening of osteoporosis. Thus, the coronal plane as well as axial and sagittal planes can be used interchangeably in measuring bone mineral density using CT.

Neurosarcoidosis involving cervical nerve root with unusual MRI findings: a case report and systematic literature review

BACKGROUND

Neurosarcoidosis is rare, and among its manifestations, nerve root involvement has been reported in only a few cases. Therefore, magnetic resonance imaging (MRI) findings of neurosarcoidosis, particularly those involving nerve roots, are scarce in the literature.

METHODS

We presented the case of neurosarcoidosis involving cervical nerve roots and cranial nerves, alongside a systematic literature review.

RESULTS

A 28-year-old female suddenly developed right facial numbness as well as left upper extremity and left hand pain. Initial brain and spine MRI showed a bulging mass of T2 iso-to-high signal intensity in the left Meckel's cave/trigeminal nerve, as well as diffuse enlargement of the right C6 and C7 nerve roots. Follow-up MRI at 2 months revealed a reduction in the size of the initial lesion and the appearance of new similar lesions on the contralateral side (right Meckel's cave, left C3-C8 nerve roots). In particular, the lesions involving the nerve roots demonstrated central enlargement along the nerve roots, without involvement of the adjacent spinal cord. All these lesions exhibited enhancement, leading to the differentiation between sarcoidosis and lymphoma. Sarcoidosis was subsequently confirmed through biopsy of a hilar lymph node.

CONCLUSIONS

This report presents a distinctive MRI feature of neurosarcoidosis involving spinal nerve roots, representing the first of its kind, and describes the evolution of MRI findings throughout the clinical course.

[Lumbar Facet Joint Injection: A Review of Efficacy and Safety]

Facet joint arthrosis is a progressive degenerative disease that is frequently associated with other spinal degenerative disorders such as degenerative disc disease or spinal stenosis. Lumbar facet joint arthrosis can induce pain in the proximal lower extremities. However, symptoms and imaging findings of "facet joint syndrome" are not specific as they mimic the pain from herniated discs or nerve root compression. Currently, evidence for therapeutic intra-articular lumbar facet joint injections is still considered low, with a weak recommendation strength. Nevertheless, some studies have reported therapeutic effectiveness of facet joint injections. Moreover, the use of therapeutic facet joint injections in clinical practice has increased. This review article includes opinions based on the authors' experience with facet joint injections. This review primarily aimed to investigate the efficacy of lumbar facet joint injections and consider their associated safety aspects.

Interlaminar versus transforaminal epidural steroid injections: a review of efficacy and safety

Spine intervention is an important treatment option for the management of spinal pain, and the numbers of the most representative epidural steroid injection (ESI) procedures performed are expected to increase significantly in the future along with increased life expectancy and the increasing prevalence of spinal disorders. Therefore, it is important to understand the efficacy of ESIs according to each spinal disorder they are administered to treat, and one must be familiar with the possible complications. In fact, although numerous ESI-related articles have been published, there is still considerable controversy regarding the efficacy of ESI procedures. Furthermore, due to the rarity of serious complications, most instances have been recorded in the form of case reports. In this article, we aimed to review the indications of cervical and lumbar ESIs and to compare interlaminar ESI (ILESI) and transforaminal ESI (TFESI) techniques in terms of analgesic efficacy, possible complications, and safety profiles. This article includes opinions based on the authors' experience with ESI indications and efficacy, and presents practical tips for coping with specific situations related to each complication. By combining the dedicated anatomical understanding of radiologists with image-guided interventions, ESI is expected to stand out in the rapidly expanding field of spine intervention.

Observation of high-energy neutrinos from the Galactic plane

The origin of high-energy cosmic rays, atomic nuclei that continuously impact Earth's atmosphere, is unknown. Because of deflection by interstellar magnetic fields, cosmic rays produced within the Milky Way arrive at Earth from random directions. However, cosmic rays interact with matter near their sources and during propagation, which produces high-energy neutrinos. We searched for neutrino emission using machine learning techniques applied to 10 years of data from the IceCube Neutrino Observatory. By comparing diffuse emission models to a background-only hypothesis, we identified neutrino emission from the Galactic plane at the 4.5σ level of significance. The signal is consistent with diffuse emission of neutrinos from the Milky Way but could also arise from a population of unresolved point sources.

Reliability and validity of a mobile application for femoral anteversion measurement in adult patients

BACKGROUND

Femoral torsion is primarily measured by computed tomography (CT), which has cost and radiation exposure concerns. Recently, femoral anteversion measurement by a simple radiograph-based mobile application was developed for patients with cerebral palsy. This study aimed to validate the use of a mobile application that can reconstruct a three-dimensional model of the femur from conventional radiographs for adults.

METHODS

Medical records of 76 patients undergoing conventional femur anteroposterior/lateral radiography and femur CT were reviewed. To measure femoral anteversion on the reconstructed 3-dimensional images from both the mobile application and CT, we drew a line which connects the posterior margins of each femoral condyle and another line which passes through the center of the femoral head and the midpoint of the femoral neck. After the reliability test, a single examiner measured femoral anteversion on the mobile application and CT. Pearson's correlation analysis was used to assess the correlation between anteversion on the mobile application and CT.

RESULTS

Femoral anteversion measured on both CT and the mobile application showed excellent reliability (intraclass correlation coefficients: 0.808-0.910). The correlation coefficient between femoral anteversion measured using CT and the mobile application was 0.933 (p < 0.001). The correlation of femoral anteversion between CT and the mobile application was relatively higher in the absence of metallic implants (correlation coefficient: 0.963, p < 0.001) than in the presence of metallic implants (correlation coefficient: 0.878, p < 0.001).

CONCLUSIONS

Using two simple radiographs, the mobile application showed excellent validity and reliability for femoral anteversion measurement in adults as compared to CT. With the high accessibility and cost-effectiveness of this mobile application, femoral torsion measurement might be easily performed with simple radiography in clinical settings in the near future.

Heterogeneous Integration of Freestanding Bilayer Oxide Membrane for Multiferroicity

Transition metal oxides exhibit a plethora of electrical and magnetic properties described by their order parameters. In particular, ferroic orderings offer access to a rich spectrum of fundamental physics phenomena, in addition to a range of technological applications. The heterogeneous integration of ferroelectric and ferromagnetic materials is a fruitful way to design multiferroic oxides. The realization of freestanding heterogeneous membranes of multiferroic oxides is highly desirable. In this study, epitaxial BaTiO₃ /La_0.7 Sr_0.3 MnO₃ freestanding bilayer membranes are fabricated using pulsed laser epitaxy. The membrane displays ferroelectricity and ferromagnetism above room temperature accompanying the finite magnetoelectric coupling constant. This study reveals that a freestanding heterostructure can be used to manipulate the structural and emergent properties of the membrane. In the absence of the strain caused by the substrate, the change in orbital occupancy of the magnetic layer leads to the reorientation of the magnetic easy-axis, that is, perpendicular magnetic anisotropy. These results of designing multiferroic oxide membranes open new avenues to integrate such flexible membranes for electronic applications.

Search for the Pair Production of Dark Particles X with K_{L}^{0}→XX, X→γγ

We present the first search for the pair production of dark particles X via K_{L}^{0}→XX with X decaying into two photons using the data collected by the KOTO experiment. No signal was observed in the mass range of 40-110  MeV/c^{2} and 210-240  MeV/c^{2}. This sets upper limits on the branching fractions as B(K_{L}^{0}→XX)<(1-4)×10^{-7} and B(K_{L}^{0}→XX)<(1-2)×10^{-6} at the 90% confidence level for the two mass regions, respectively.

MR evaluation of the posteromedial corner of the knee: association of posterior horn medial meniscus tear with posterior oblique ligament and distal semi-membranosus tendon tear

OBJECTIVE

To assess if posterior oblique ligament and distal semi-membranosus tendon tears are associated with posterior horn medial meniscus tears on MRI.

METHODS

From January 1, 2018 to December 31, 2019, 56 patients who met the inclusion criteria were enrolled in this study. Of the 56 patients, 43 patients who had a posterior horn of medial meniscus tear were included in the study group. A control group of 13 individuals was formed for comparison. Two radiologists reviewed the MR images and recorded the presence and grades of posterior oblique ligament and distal semi-membranosus tendon tears. We used the independent t-test and one-way ANOVA to compare the tear grades. Interobserver agreement was analyzed using a Cohen's κ coefficient (κ value) for categorical variables.

RESULTS

The mean grades for the posterior oblique ligament and distal semi-membranosus tendon tears were significantly higher in the study group (all, p < 0.001). Interobserver agreement between the two readers was substantial in assessing the grade of posterior oblique ligament tear (κ = 0.653±0.087) and almost perfect in assessing the grade of distal semi-membranosus tendon tear (κ = 0.876±0.060).

CONCLUSION

Posterior oblique ligament and distal semi-membranosus tendon tears are significantly associated with posterior horn of medial meniscus tear and medial meniscus posterior root tears, and the peel-back mechanism could be related to this association.

ADVANCES IN KNOWLEDGE

Presenting this paper could adjust radiologist search patterns and potentially help orthopedists with management and pre-surgical planning for the posteromedial corner injury of the knee.

Magnetic Resonance Imaging Grading Systems for Central Canal and Neural Foraminal Stenoses of the Lumbar and Cervical Spines With a Focus on the Lee Grading System

Magnetic resonance imaging (MRI) is a standard imaging modality for diagnosing spinal stenosis, which is a common degenerative disorder in the elderly population. Standardized interpretation of spinal MRI for diagnosing and grading the severity of spinal stenosis is necessary to ensure correct communication with clinicians and to conduct clinical research. In this review, we revisit the Lee grading system for central canal and neural foraminal stenosis of the cervical and lumbar spine, which are based on the pathophysiology and radiologic findings of spinal stenosis.

Dual-layer spectral detector CT arthrography of the shoulder: assessment of image quality and value in differentiating calcium from iodine

BACKGROUND

Dual-layer spectral detector computed tomography (DLCT) may potentially improve CT arthrography through enhanced image quality and analysis of the chemical composition of tissue.

PURPOSE

To evaluate the image quality of monoenergetic reconstructions from DLCT arthrography of the shoulder and assess the additional diagnostic value in differentiating calcium from iodine.

MATERIAL AND METHODS

Images from consecutive shoulder DLCT arthrography examinations performed between December 2016 and February 2018 were retrospectively reviewed for hyperattenuating lesions within the labrum and tendons. The mean attenuation of the target lesion, noise, contrast-to-noise ratio (CNR), and signal-to-noise ratio (SNR) of the virtual monoenergetic images obtained at 40-200 keV were compared with conventional 140-kVp images. Two evaluators independently classified each target lesion as contrast media or calcification, without and with DLCT spectral data. Receiver operating curve (ROC) analysis was performed to assess the diagnostic performance of shoulder DLCT arthrography, without and with the aid of spectral data.

RESULTS

The study included 20 target lesions (18 DLCT arthrography examinations of 17 patients). The SNRs of the monoenergetic images at 40-60 keV were significantly higher than those of conventional images (P < 0.05). The CNRs of the monoenergetic images at 40-70 keV were significantly higher than those of conventional images (P < 0.001). The ability to differentiate calcium from iodine, without and with DLCT spectral data, did not significantly differ (P = 0.441 and P = 0.257 for reviewers 1 and 2, respectively).

CONCLUSION

DLCT had no additive value in differentiating calcium from iodine in small, hyperattenuating lesions in the labrum and tendons.

Comparison of Effect and Contrast Spreading in Transforaminal Epidural Injection Using the Retrodiscal Versus Subpedicular Approach: A Prospective, Randomized Trial

BACKGROUND

Lumbar transforaminal epidural injection (TFEI) effectively decreases low back pain and radicular pain in herniated intervertebral disc (HIVD) and spinal stenosis (SS). The precise delivery of drugs to the target is important for pain control and minimizing complications.

OBJECTIVES

We aimed to evaluate the efficacy and complications of the subpedicular (SP) and retrodiscal (RD) approaches by analysis of contrast spread patterns into the pathologic target on the basis of a newly established specific criterion. We also investigated whether the severity of patients' spinal disease influenced this pattern.

STUDY DESIGN

A prospective, randomized, observational study.

SETTING

Interventional pain management center at a university-affiliated hospital.

METHODS

Among patients who showed lumbar spinal stenosis or HIVD at the L4/5 level, participants were randomly assigned to undergo TFEI with the SP approach (SP group) or RD approach (RD group). Pain relief in terms of the visual analog scale (VAS) score and complications such as intravascular or intradiscal uptake were also analyzed. The contrast image was analyzed as the contrast media was injected, starting from 0.5 mL up to 3.0 mL. The spread patterns of contrast media were graded into 4 categories, which were newly defined in this study.

RESULTS

Both groups demonstrated a significant decrease in pain relief (P value < 0.01) at 2 and 4 weeks after the procedures, but no significant difference was found between the 2 groups. In the intergroup analysis between the RD and SP groups, with a 1.5-mL contrast media injection, more patients in the RD group (17.2%) showed a grade 3 spread than those in the SP group (8.2%). In the subgroup analysis, the RD group showed superior spread (more grade 3 and 4) with 1.5-, 2-, and 2.5-mL contrast media injections (P values = 0.02, 0.03, and 0.04) in severe central stenosis, and 1.5- and 2-mL contrast media injections (P values = 0.01, 0.02) in severe foraminal stenosis.

LIMITATIONS

The follow-up period was only 4 weeks after TFESI, and higher contrast injection was used for procedures.

CONCLUSIONS

The RD approach for TFEI showed a better contrast spreading pattern than the SP approach, especially in patients with severe central and foraminal spinal stenosis. The RD approach might be more beneficial for patients with severe central and foraminal spinal stenosis in the short-term follow-up.

Value of computed tomography Hounsfield units in predicting pedicle screw loosening in the thoracic spine

We evaluated the feasibility of using the Hounsfield unit (HU) value of the vertebral body to predict screw loosening in the thoracic spine. Consecutive patients who underwent thoracic spinal fusion surgery (from 2014 to 2020) were retrospectively identified. Patients with pedicle screw loosening in the upper instrumented vertebra (UIV) on postoperative computed tomography were included in the "loosening" group. The control group comprised an equal number of age-, sex-, and UIV-matched patients without screw loosening. Preoperative HU values at the UIV and lumbar T-scores were compared between the groups; receiver operating characteristic curves were constructed for HU values and T-scores to predict screw loosening, and the best cutoff values were determined. The same statistical analyses were performed for each subgroup, i.e., upper (T1-T4) and lower (T9-T12) thoracic levels. Forty-six patients each were included in the loosening and control groups. A significant between-group difference of HU values was noted for the lower thoracic UIV (loosening = 99.3, control = 126.3; p = 0.02) but not for the upper thoracic UIV (loosening = 171.8, control = 146.0, p = 0.70). T-scores did not differ between the groups for the lower (p = 0.14) and upper (p = 0.56) thoracic UIV. For the lower thoracic UIV, the area under the receiver operating characteristic curve was 0.660 for HUs (p = 0.01; 95% confidence interval [CI] 0.541-0.766) and 0.601 (p = 0.13; 95% CI 0.480-0.713) for T-scores. The optimal cutoff value for HUs was 126.3. Using this cutoff, HU values showed a better positive predictive value, negative predictive value, and accuracy compared to T-scores in predicting screw loosening.

Search for Unstable Sterile Neutrinos with the IceCube Neutrino Observatory

We present a search for an unstable sterile neutrino by looking for a resonant signal in eight years of atmospheric ν_{μ} data collected from 2011 to 2019 at the IceCube Neutrino Observatory. Both the (stable) three-neutrino and the 3+1 sterile neutrino models are disfavored relative to the unstable sterile neutrino model, though with p values of 2.8% and 0.81%, respectively, we do not observe evidence for 3+1 neutrinos with neutrino decay. The best-fit parameters for the sterile neutrino with decay model from this study are Δm_{41}^{2}=6.7_{-2.5}^{+3.9}  eV^{2}, sin^{2}2θ_{24}=0.33_{-0.17}^{+0.20}, and g^{2}=2.5π±1.5π, where g is the decay-mediating coupling. The preferred regions of the 3+1+decay model from short-baseline oscillation searches are excluded at 90% C.L.

Intra-individual comparison of lumbar spine CT, abdomen-pelvis contrast enhanced CT, and low-dose chest CT for bone density measurement

BACKGROUND

Dual-energy X-ray absorptiometry (DXA) is the reference standard for the measurement of bone mineral density (BMD) and subsequent diagnosis of osteoporosis. Since various computed tomography (CT) protocols are scanned for various indications, we can incidentally measure BMD using CT. Previous studies have revealed a correlation between BMD and Hounsfield unit (HU) values obtained with different CT protocols.

PURPOSE

To compare the diagnostic value of CT protocols (lumbar spine CT [LSCT], abdomen-pelvis contrast-enhanced CT [APCT], and low-dose chest CT [LDCT]) for osteoporosis.

MATERIAL AND METHODS

We retrospectively included 17 patients (6 men, 11 women; mean age=68 years) who had undergone all four imaging studies within six months, during 2011-2021. HU values were manually measured at the center of the L1 vertebra by a radiology resident. Pearson correlation test was performed between HU values and BMD of L1 vertebra. The diagnostic performance of each CT protocol was assessed with receiver operating characteristic (ROC) analysis. Intra-individual concordance of the four tests to diagnose osteoporosis was analyzed by tabulating.

RESULTS

The mean HU values were 104.4 ± 47.2 HU with LSCT, 149.0 ± 56.9 HU with APCT, and 114.3 ± 60.0 HU with LDCT. HU values from each protocol were positively correlated (r = 0.676-0.735; P < 0.005) with BMD. LDCT had the highest diagnostic performance (area under the ROC curve [AUC] = 0.701) and APCT the lowest (AUC = 0.569). APCT was discordant with the other protocols for diagnosing osteoporosis.

CONCLUSION

LDCT had the highest diagnostic performance for osteoporosis with predetermined cutoff value. APCT requires the increase of cutoff value for osteoporosis diagnosis.

Fluoroscopic lumbar transforaminal epidural steroid injections for recurrent herniated intervertebral disc after discectomy: Effectiveness and outcome predictors

Background

Despite transforaminal epidural steroid injection (ESI) being the first choice in patient with recurrent herniated intervertebral disc (HIVD), efficacy of ESI in those patients are not well established. Herein, we evaluate the effectiveness and outcome predictors of fluoroscopic transforaminal ESI for recurrent HIVD.

Methods

Seventy-seven patients (48 male; mean age, 51.3 years) with recurrent lumbar HIVD were included and divided into three groups according to initial treatment: conservative treatment, transforaminal ESI, and immediate surgery. ESI effectiveness was evaluated by operation rates, injection numbers in 6 months, and pain reduction (visual analog scale (VAS) scores). Clinical and MRI variables were analyzed as possible outcome predictors. Each subject in the transforaminal ESI group was individually matched to two patients with initial HIVD (control group).

Results

In the transforaminal ESI group (n = 37), 20 patients (54.1%) did not undergo reoperation. The initial and follow-up VAS scores were significantly higher in the reoperation group (p = 0.014, p = 0.019, respectively). Patients with either paresthesia or motor weakness (12/19, 63.2%) had a significantly higher reoperation rate than patients with only pain (5/18, 27.8%; p = 0.031). Extruded disc ratios ≥2.0 were significantly higher in the reoperation group (10/17, 58.8%; p = 0.048). The reoperation rate in the transforaminal ESI group (17/37, 45.9%) was higher than the operation rate in the control group (6/73, 8.2%; p<0.001).

Conclusion

Transforaminal ESI was effective in reducing radicular pain in patients with recurrent HIVD. Approximately 54% of patients did not undergo reoperation. An extruded disc ratio ≥2.0 and paresthesia or motor weakness were poor outcome predictors.

Strong Constraints on Neutrino Nonstandard Interactions from TeV-Scale ν_{μ} Disappearance at IceCube

We report a search for nonstandard neutrino interactions (NSI) using eight years of TeV-scale atmospheric muon neutrino data from the IceCube Neutrino Observatory. By reconstructing incident energies and zenith angles for atmospheric neutrino events, this analysis presents unified confidence intervals for the NSI parameter ε_{μτ}. The best-fit value is consistent with no NSI at a p value of 25.2%. With a 90% confidence interval of -0.0041≤ε_{μτ}≤0.0031 along the real axis and similar strength in the complex plane, this result is the strongest constraint on any NSI parameter from any oscillation channel to date.

Evaluation of the efficacy and safety of epidural steroid injection using a nonparticulate steroid, dexamethasone or betamethasone: a double-blind, randomized, crossover, clinical trial

Background

The U.S. Food and Drug Administration has prohibited epidural steroid injection (ESI) with particulate steroids. Thus, this study aimed to compare the efficacy and safety of ESI with two nonparticulate steroids, dexamethasone and betamethasone.

Methods

The eligible patients (n = 600) who received ESI (0 week) with dexamethasone (ESI-dexa) or betamethasone (ESI-beta) had follow-up visits at 2, 4, and 8 weeks with a phone interview at 12 weeks. The primary endpoint was the proportion of effective responders without pain or who were much improved at 2 weeks. The secondary endpoints were the proportion of crossover injections at 2 weeks; changes in the visual analog scale (VAS) and disability index scores at 2, 4, and 8 weeks; the number of additional ESIs in 12 weeks; the number of participants having spinal surgery, as well as the incidence of adverse events over the 12 weeks.

Results

The proportion of effective responders at 2 weeks was not different between ESI-beta (72/216, 33.3%) and ESI-dexa (63/200, 31.5%; P = 0.670). Adverse events were more common with ESI-dexa (40/200, 20.0%) than with ESI-beta (24/216, 11.1%; P = 0.012). VAS scores decreased more with ESI-beta than with ESI-dexa at 2 weeks (difference, 0.35; P = 0.023) and 4 weeks (difference, 0.42; P = 0.011). The disability score improved significantly more with ESI-beta compared with ESI-dexa at 2 weeks (difference, 3.37; P = 0.009), 4 weeks (difference, 4.01; P = 0.002), and 8 weeks (difference, 3.54; P = 0.007).

Conclusions

Betamethasone would be more appropriate for ESI.

Texture analysis of magnetic resonance image to differentiate benign from malignant myxoid soft tissue tumors: A retrospective comparative study

It is important to differentiate between benign and malignant myxoid tumors to establish the treatment plan, determine the optimal surgical extent, and plan postoperative surveillance, but differentiation may be complicated by imaging-feature overlap. Texture analysis is used for quantitative assessment of imaging characteristics based on mathematically calculated pixel heterogeneity and has been applied to the discrimination of benign from malignant soft tissue tumors (STTs). In this study, we aimed to assess the diagnostic value of the texture features of conventional magnetic resonance images for the differentiation of benign from malignant myxoid STTs. Magnetic resonance images of 39 patients with histologically confirmed myxoid STTs of the extremities were analyzed. Qualitative features were assessed and compared between the benign and malignant groups. Texture analysis was performed, and texture features were selected based on univariate analysis and Fisher’s coefficient. The diagnostic value of the texture features was assessed using receiver operating curve analysis. T1 heterogeneity showed a statistically significant difference between benign and malignant myxoid STTs, with substantial inter-reader reliability. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of T1 heterogeneity were 55.6%, 83.3%, 88.2%, 45.5%, and 64.1%, respectively. Among the texture features, T2w-WavEnLL_s-3 showed good diagnostic performance, and T2w-WavEnLL_s-4 and GeoW4 showed fair diagnostic performance. The logistic regression model including T1 heterogeneity and T2_WavEnLL_s-4 showed good diagnostic performance. However, there was no statistically significant difference between the overall qualitative assessment by a radiologist and the predictor model. Geometry-based and wavelet-derived texture features from T2-weighted images were significantly different between benign and malignant myxoid STTs. However, the texture features had a limited additive value in differentiating benign from malignant myxoid STTs.

Skin manifestations and clinical features of drug reaction with eosinophilia and systemic symptoms (DRESS): A retrospective multicenter study of 125 patients

BACKGROUND

Drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe adverse drug reaction generally accompanied by skin manifestations as the first and most frequent symptoms. However, skin manifestations and associated clinical features of DRESS have not been fully explored and evaluated.

OBJECTIVES

This study aimed to describe the skin manifestations of DRESS in detail and analyze their association with demographic characteristics and extra-cutaneous clinical features.

METHODS

We conducted this retrospective study on patients with DRESS diagnosed between September 2009 and August 2021 at three medical institutes and validated using the RegiSCAR score. Data regarding demographics, skin manifestations, and clinical characteristics were retrieved through thorough chart reviews.

RESULTS

Among 182 potential cases of DRESS, the validated 125 cases were analyzed. A widespread rash extending over more than 50% of the body surface area was observed in 122 patients (97.6%) and typical facial edema was experienced by 67 patients (53.6%). Polymorphous maculopapules were the most common rash morphology (106, 84.8%): specifically, exfoliative (59, 47.2%), urticarial (57, 45.6%), and purpuric forms (39, 31.2%) were common. Mucosal involvement was observed in 41 patients (32.8%). Patients with carboxamide antiepileptics (carbamazepine and oxcarbazepine) experienced more edema (P = .014) and typical facial edema than those with allopurinol (P = .021). The RegiSCAR score was higher in patients with purpura (P < .01).

CONCLUSIONS

Skin manifestations of DRESS exhibit a wide range of skin lesions and can vary according to the culprit drugs. Early suspicion and prompt intervention are needed to improve prognosis.

Search for Relativistic Magnetic Monopoles with Eight Years of IceCube Data

We present an all-sky 90% confidence level upper limit on the cosmic flux of relativistic magnetic monopoles using 2886 days of IceCube data. The analysis was optimized for monopole speeds between 0.750c and 0.995c, without any explicit restriction on the monopole mass. We constrain the flux of relativistic cosmic magnetic monopoles to a level below 2.0×10^{-19}  cm^{-2} s^{-1} sr^{-1} over the majority of the targeted speed range. This result constitutes the most strict upper limit to date for magnetic monopoles with β≳0.8 and up to β∼0.995 and fills the gap between existing limits on the cosmic flux of nonrelativistic and ultrarelativistic magnetic monopoles.

Effectiveness of epidural steroid injection in patients with lumbar herniated intervertebral disc under a "wait-and-see" policy

BACKGROUND

There are no consensus and guidelines on the optimal interval of repeat epidural steroid injections (ESI) for patients with lumbar herniated intervertebral disc (HIVD) who respond to initial ESI.

PURPOSE

To evaluate the effectiveness of ESI in patients with HIVD under a "wait-and-see" policy, i.e. as-needed injections not on a predetermined schedule.

MATERIAL AND METHODS

A total of 592 patients with lumbar HIVD received spine injections between January and December 2017. After excluding patients with excellent (no pain) or poor (>70% residual symptoms) response in the two- or three-week pain assessment, the data of 141 responders were analyzed (60 men, 73 women; age = 50.55±17.25 years). We divided patients into wait-and-see (n=124) and early repeat-ESI (n=17) groups, who received repeat ESIs within three weeks. Evaluations of characteristics and outcomes were performed with the chi-square test or independent Student's t-test.

RESULTS

Six patients (4.8%) in the wait-and-see group and 1 (5.9%) in the early repeat-ESI group underwent operation within one year (P=0.85). A mean of 1.52±0.82 ESIs was performed in the wait-and-see and a mean of 2.29±0.47 ESIs in the early repeat-ESI group over one year (P<0.001). The time interval between the first and second ESIs was longer in the wait-and-see group than in the early repeat-ESI group (97.15 vs. 15.47 days, P<0.001). Seventy-eight patients (62.9%) in the wait-and-see group could control their pain with a single ESI.

CONCLUSION

A "wait-and-see" policy could be an effective pain management option for patients with lumbar HIVD who respond to initial ESI.

Predicting the clinically significant subscapularis tendon tear: malposition and tear of the long head of the biceps tendon on shoulder magnetic resonance imaging

BACKGROUND

The diagnostic accuracy of magnetic resonance imaging (MRI) is low for detecting a subscapularis tendon tear.

PURPOSE

To identify MRI findings that may predict the presence of a clinically significant subscapularis tendon tear requiring surgical repair.

MATERIAL AND METHODS

We reviewed shoulder MR images of patients who had undergone arthroscopic rotator cuff repair at our institution between June 2018 and May 2019. Patients were divided into two groups: the study group (n = 51), with an intermediate- to high-grade partial thickness tear of the subscapularis tendon suspected on preoperative MRI and intermediate or higher grade of the tendon tear proven on arthroscopy; and the control group (n = 18), with an intermediate- to high-grade partial thickness tear of the subscapularis tendon suspected on preoperative MRI but no tear or low-grade partial thickness tear of the tendon shown on arthroscopy. Preoperative MR images were retrospectively evaluated by two readers for the size of the subscapularis tendon tear, bone reactions at the lesser tuberosity, and long head of the biceps tendon (LHBT) pathology.

RESULTS

The subscapularis tendon tear measured by reader 2 was larger in the study group than in the control group. The prevalence of a tear (P = 0.006 for reader 1; P = 0.011 for reader 2) and malposition (P < 0.001 for both readers) of the LHBT were significantly greater in the study group.

CONCLUSION

A tear and malposition of the LHBT on MR images may predict the presence of a clinically significant subscapularis tendon tear.

Effects of hydrogenated fat-spray-coated β-carotene supplement on plasma β-carotene concentration and conception rate after embryo transfer in Hanwoo beef cows

We hypothesised that hydrogenated fat (HF)-spray-coated β-carotene (βC) supplement could be used to increase plasma βC concentration and conception rates after embryo transfer (ET) in Hanwoo beef cows. In Experiment 1, 12 multiparous Hanwoo cows were fed one of four experimental diets in a triplicate 4 × 4 Latin square design for a 28-day period. Treatments included no βC addition (control), HF-uncoated βC (HFuβC), HF-spray-coated βC (HFβC), and HF-spray-coated βC and vitamin A (HFβCA). The cows under βC-supplemented treatments were fed 400 mg/day of βC, and a daily intake for vitamin A of HFβCA treatment was 30 000 IU/day as retinyl acetate. Blood was collected on days 0, 26, 27, and 28 to analyse βC and other metabolite concentrations. In Experiment 2, 199 Hanwoo cows with low fertility were randomly assigned to either control (n = 99) or HFβC treatments (n = 100) based on the results of Experiment 1. The oestrus of the cows was synchronised for ET. The HFβC group was fed from 4 weeks before to 4 weeks after ET with a daily intake of 400 mg βC. Pregnancy for conception rates was diagnosed on day 60 after ET, and blood was collected for βC concentrations on the day before ET. Supplementing βC resulted in a high plasma βC concentration (P < 0.001). Supplementing HFβC or HFβCA resulted in higher βC concentrations than HFuβC (P < 0.001); however, there was no difference between HFβC and HFβCA groups. Plasma retinol concentration was lower in the HFβCA treatment than in the control and HFβC groups (P < 0.05). Blood metabolites were unaffected by the treatments. The retinol:βC ratio was lower in the βC-supplemented treatments than in the controls, and was lower in HFβC and HFβCA than in HFuβC groups (P < 0.001). Plasma βC concentration was positively correlated with plasma high-density lipoprotein, low-density lipoprotein, and total cholesterol (P < 0.05). Plasma retinol concentration was negatively associated with plasma protein (P < 0.01), but positively associated with plasma creatinine (P < 0.001) and urea (P < 0.01). Supplementing HFβC to low-fertility cows resulted in higher plasma βC concentration (P < 0.001) and conception rates (P = 0.024) than those in the controls. In conclusion, HFβC had a better bioavailability than HFuβC, and an increase in conception rates by supplementing HFβC may be beneficial for producing more calves given the low pregnancy rates of bovine ET in Korea.

Solar background noise mitigation using the orbital angular momentum mode in vertical FSO downlink transmissions

Free-space optical communication (FSO) is used to provide network configuration flexibility. A network-flying platform-based vertical FSO connection can be employed to enhance mobile network coverage and capacity. Solar background noise can be a potential risk that disrupts the seamless connection in the vertical FSO downlink channel. In this paper, we propose signal transmission using an orbital angular momentum (OAM) beam. The OAM demodulation process can filter sunlight out of the optical receiver except for the signal corresponding to the azimuthal state. We experimentally verified that most of the solar background noise could be reduced. To verify the feasibility of the proposed scheme in a vertical FSO channel, we modeled a FSO vertical downlink with an OAM modulation/demodulation process.

Immediate postoperative MRI findings after lumbar decompression surgery: Correlation of imaging features with clinical outcome

An understanding of the common MRI findings observed after decompression surgery is important. However, to date, no study addressing this has been published. The aim of this study was to analyze and describe the immediate postoperative MRI findings after lumbar decompression surgery. We retrospectively analyzed the immediate postoperative MRIs of 121 consecutive patients who underwent lumbar decompression surgery between July 2017 and June 2018. Changes in stenosis at the decompressed and adjacent levels, epidural fat edema, epidural and subdural fluid collections, nerve root swelling, facet joint effusions, intervertebral disc signal, and paravertebral muscle edema were correlated with clinical characteristics. Both groups had reduced central canal stenosis postoperatively (p < 0.001) but worsened stenosis at adjacent segments. Fluid collection, hemorrhagic or non-hemorrhagic, at the laminectomy site was the commonest finding (one-level: 73.8%, two-level: 88.5%), with a higher percentage of severe central canal compromise in the two-level decompression group (p = 0.003). Other postoperative MRI findings, such as epidural fat edema, nerve root swelling, subdural fluid collection, and facet joint effusion, were noted without statistical significance. In conclusion, even with successful decompression for lumbar canal stenosis, increased central canal stenosis at adjacent segments is common on immediate postoperative MRI scans, showing no statistically significant correlation with the immediate postoperative outcome. Postoperative fluid collection at the laminectomy site is the commonest imaging finding, and higher rates of hemorrhagic fluid and more severe central canal compromise occur in two-level decompression, but rarely cause clinical problems.

The SπRIT time projection chamber

The Superconducting Analyzer for MUlti-particles from RAdioIsotope (SAMURAI) Pion-Reconstruction and Ion-Tracker Time Projection Chamber (SπRIT TPC) was designed to enable measurements of heavy ion collisions with the SAMURAI spectrometer at the RIKEN radioactive isotope beam factory and provides constraints on the equation of state of neutron-rich nuclear matter. The SπRIT TPC has a 50.5 cm drift length and an 86.4 × 134.4 cm² pad plane with 12 096 pads that are equipped with the generic electronics for TPCs. The SπRIT TPC allows for an excellent reconstruction of particles and provides isotopic resolution for pions and other light charged particles across a wide range of energy losses and momenta. The details of the SπRIT TPC are presented, along with discussion of the TPC performance based on cosmic rays and charged particles emitted in heavy ion collisions.

Readability of extraspinal organs on scout images of lumbar spine MRI according to different protocols

Background

Scout images of lumbar spine MRI often include the extraspinal organs, which are barely included in routine MRI and can be a potential cause of lumbar pain.

Purpose

To evaluate the readability of scout images for extraspinal organs in lumbar spine MRI according to different protocols.

Materials and methods

A total of 150 patients who underwent 1.5 T or 3 T lumbar spine MRI from March to September 2015 at three hospitals with different scout image protocols, were selected. Two radiologists independently reviewed the scout images to investigate whether exclusive diagnosis of major diseases involving the femoral head, femoral neck, sacroiliac joint, and kidneys was possible. Readability levels were divided into four categories: definitely, possibly, limited, and non-evaluable. The readability of scout images according to the protocols was compared using Chi-square test. Interobserver agreement for the readability level of scout images was assessed using weighted κ statistics.

Results

Of 150 patients, “definitely evaluable” cases classified by two readers were 50–62 (33.3–41.3%) for femoral head (κ = 0.63–0.71), 37–66 (24.7–44.0%) for femoral neck (κ = 0.41–0.48), 72–93 (48.0–62.0%) for sacroiliac joint (κ = 0.35–0.37), and 63–73 (42.0–48.7%) for kidneys (κ = 0.45–0.47). More than 50% of femoral heads were classified as readable (definitely or possible evaluable) cases by two readers with excellent interobserver agreement. The readability level of scout images was significantly different according to image protocols including the MRI sequence, number of coronal plane slices, and intersection gap of coronal plane slices (p≤0.015).

Conclusion

Scout images of lumbar spine MRI may be readable enough to rule out some major diseases of extraspinal organs. Standardization of the protocol will be needed to validate the potential role of scout images for screening extraspinal organs.

Sporadic Intradural Extramedullary Hemangioblastoma Not Associated with von Hippel-Lindau Syndrome: A Case Report and Literature Review

Hemangioblastomas are low-grade, highly vascular tumors that are usually associated with von Hippel-Lindau syndrome. Hemangioblastomas most commonly occur in the cerebellum, and intradural extramedullary hemangioblastoma of the cauda equina is very rare, especially in patients without von Hippel-Lindau syndrome. Herein, we report a case of intradural extramedullary hemangioblastoma of the cauda equina that was not associated with von Hippel-Lindau syndrome, with a focus on its imaging characteristics and differential diagnoses. We compared the clinical presentation and imaging features of our case with those of previously reported cases in the review of the literature.

Probing the Symmetry Energy with the Spectral Pion Ratio

Many neutron star properties, such as the proton fraction, reflect the symmetry energy contributions to the equation of state that dominate when neutron and proton densities differ strongly. To constrain these contributions at suprasaturation densities, we measure the spectra of charged pions produced by colliding rare isotope tin (Sn) beams with isotopically enriched Sn targets. Using ratios of the charged pion spectra measured at high transverse momenta, we deduce the slope of the symmetry energy to be 42<L<117  MeV. This value is slightly lower but consistent with the L values deduced from a recent measurement of the neutron skin thickness of ^{208}Pb.

Study of the K_{L}→π^{0}νν[over ¯] Decay at the J-PARC KOTO Experiment

The rare decay K_{L}→π^{0}νν[over ¯] was studied with the dataset taken at the J-PARC KOTO experiment in 2016, 2017, and 2018. With a single event sensitivity of (7.20±0.05_{stat}±0.66_{syst})×10^{-10}, three candidate events were observed in the signal region. After unveiling them, contaminations from K^{±} and scattered K_{L} decays were studied, and the total number of background events was estimated to be 1.22±0.26. We conclude that the number of observed events is statistically consistent with the background expectation. For this dataset, we set an upper limit of 4.9×10^{-9} on the branching fraction of K_{L}→π^{0}νν[over ¯] at the 90% confidence level.

Accurate Imputation of Greenhouse Environment Data for Data Integrity Utilizing Two-Dimensional Convolutional Neural Networks

Greenhouses require accurate and reliable data to interpret the microclimate and maximize resource use efficiency. However, greenhouse conditions are harsh for electrical sensors collecting environmental data. Convolutional neural networks (ConvNets) enable complex interpretation by multiplying the input data. The objective of this study was to impute missing tabular data collected from several greenhouses using a ConvNet architecture called U-Net. Various data-loss conditions with errors in individual sensors and in all sensors were assumed. The U-Net with a screen size of 50 exhibited the highest coefficient of determination values and the lowest root-mean-square errors for all environmental factors used in this study. U-Net50 correctly learned the changing patterns of the greenhouse environment from the training dataset. Therefore, the U-Net architecture can be used for the imputation of tabular data in greenhouses if the model is correctly trained. Growers can secure data integrity with imputed data, which could increase crop productivity and quality in greenhouses.

Psoriasis is associated with an increased risk of osteoporosis: follow-up and nested case-control studies using a national sample cohort

A total of 25,306 psoriasis participants were matched to 101,224 controls, and the occurrence of osteoporosis was analyzed. Additionally, 79,212 osteoporosis patients were matched to 79,212 controls and a previous history of psoriasis was analyzed. Psoriasis increased the risk of osteoporosis among participants aged ≥ 40 years.

INTRODUCTION

The aim of the present study was to evaluate the association between psoriasis and osteoporosis using two different studies.

METHODS

Data from the Korean National Health Insurance Service-Health Screening Cohort of participants aged ≥ 40 years were collected from 2002 to 2013. Psoriasis and osteoporosis were included using International Classification of Diseases (ICD)-10 codes. In study I (a follow-up study), a total of 25,306 psoriasis participants were matched to 101,224 controls with respect to age, sex, income, and region of residence, and the occurrence of osteoporosis was analyzed. Crude (simple) and adjusted hazard ratios (HRs) were analyzed using a stratified Cox proportional hazard model. In study II (a nested case-control study), a total of 79,212 osteoporosis patients were matched to 79,212 controls and a previous history of psoriasis was analyzed. Crude and adjusted odds ratios (ORs) were analyzed using a conditional logistic regression analysis. Subgroup analyses were conducted according to age group and sex.

RESULTS

The adjusted HR of osteoporosis was 1.09 (95% confidence interval [CI] = 1.05-1.13, P < 0.001) in study I. In the subgroup analysis according to age and sex, the results were consistent except for ≥ 60-year-old women. The adjusted OR of psoriasis was 1.21 (95% CI = 1.16-1.27, P < 0.001) in study II. All subgroups demonstrated high adjusted ORs of osteoporosis for psoriasis.

CONCLUSIONS

Psoriasis increased the risk of osteoporosis among participants aged ≥ 40 years in Korea.

The comparison of recovery patterns between ischemic spinal cord injury and traumatic spinal cord injury from acute to chronic phase

Objective: To investigate the neurological and functional recovery patterns of ischemic spinal cord injury (ISCI) compared with traumatic spinal cord injury (TSCI) in the acute to chronic phase.Design: Retrospective cohort study.Settings: Department of Neurology, Neurosurgery, Rehabilitation Medicine at a tertiary hospital.Participants: Fifty-four patients with ISCI and 86 patients with TSCI.Interventions: Not applicable.Outcome measures: MRI findings, American Spinal Injury Association Impairment Scale (AIS), modified Rankin Scale (mRS), Korean Spinal Cord Independence Measure (KSCIM), ambulatory status, and bladder status were reviewed. The functional outcomes were measured at admission, discharge, and >6 months after discharge.Results: AIS classification did not significantly change after 6 months in both ISCI and TSCI groups. Between admission and discharge, the proportion of patients needing a wheelchair or assistive device to ambulate decreased more in the ISCI group compared with the TSCI group [odds ratio (OR) 0.40, P = 0.04]. In addition, the proportion of catheterized voiding in the ISCI group was significantly higher than in the TSCI group at all time points (OR 5.12, P < 0.001). Lastly, both groups showed that functional improvement was the greatest between admission and discharge. In addition, the proportion of catheterized voiding decreased (Diff = -0.12, P = 0.019) and mRS score decreased (Diff=-0.48, P < 0.001) significantly in the ISCI group at >6 months post discharge.Conclusion: The ISCI group showed better recovery of mobility during inpatient rehabilitation period and worse recovery of bladder function as demonstrated by higher number of patients requiring bladder catheterization at all time points when compared with the TSCI group.

Sonographic Appearance of Steatocystoma: An Analysis of 14 Pathologically Confirmed Lesions

Purpose

To evaluate the ultrasonographic characteristics of steatocystomas focusing on the features that aid in differentiating them from epidermal inclusion cysts and lipomas.

Materials and Methods

The ultrasonographic findings of 14 histologically proven steatocystomas in 10 patients were retrospectively reviewed. The following features were assessed: the layer of involvement, shape, margin, echogenicity, posterior acoustic features, and the presence of a visible wall or intralesional striations. The findings were compared with those of subcutaneous lipomas and epidermal inclusion cysts to identify those findings that aid in the differential diagnosis of steatocystomas.

Results

The majority of steatocystomas appeared as a subcutaneous mass (n = 6, 42.9%) or a mass involving both the dermal and subcutaneous layers (n = 6, 42.9%). Steatocystomas exhibited a well-defined smooth margin (n = 12, 85.7%) and homogeneous echogenicity (n = 9, 64.3%), and showed no specific posterior acoustic features (n = 9, 64.3%). The most important features that differentiated steatocystomas from epidermal inclusion cysts were a homogeneous internal echotexture (p = 0.009) and absent or less prominent posterior acoustic enhancement (p < 0.001). The features that distinguished steatocystomas from lipomas were the margin (p < 0.001), echogenicity (p = 0.034), internal echotexture (p = 0.004), and the absence of intralesional striations (p < 0.001).

Conclusion

Steatocystomas appeared as well-defined homogeneous masses with mild or absent posterior acoustic enhancement.

Non-relaxor behaviour of low-frequency vibration spectra of relaxor ferroelectric PbCo1/3Nb2/3O3: evidences from Brillouin and Raman scattering measurements

This paper presents the results of studies of a low-frequency vibration spectrum of PbCo_1/3Nb_2/3O₃ (PCN) relaxor ferroelectric crystal using the Brillouin and Raman light scattering in the temperature range from 80 to 750 K. The analysis of the temperature behaviour of the longitudinal acoustic phonon in Brillouin scattering spectra showed no anomalies in the vicinity of 'diffuse phase transition' (T _m = 250 K) in PCN. Polarized Raman light scattering spectra were obtained in PCN over the entire temperature range studied. Analysis of low-frequency optical mode behaviour in PCN during temperature change also revealed no correlations with dielectric permeability anomaly in the vicinity of T _m: softening of optical phonon at 43 cm^-1 frequency in VV polarization is observed at 170 K. In the same temperature range, there are anomalies (a 'narrow' and weak component) in quasi-elastic light scattering (QELS) obtained in temperature behaviour with VH polarization in Raman spectra in PCN. A 'wide' and intense QELS component, obtained in Raman spectra with VV polarization, shows anomalies in the vicinity of T _m. We associate the anomalies of optical phonons and QELS with structure distortions in the formation of phase stratification and the dynamics of polar nano-regions.

Efficacy of Fluoroscopy-Guided Lumbar Facet Joint Synovial Cyst Rupture with Intra-Articular Steroid Injection after Laminectomy

PURPOSE

We retrospectively evaluated the technical success rate and long-term efficacy of fluoroscopy-guided synovial cyst rupture followed by an intra-articular steroid injection at the post-laminectomy lumbar facet.

MATERIALS AND METHODS

We selected subjects who had undergone a fluoroscopy-guided synovial cyst rupture with simultaneous intra-articular steroid injection within 6 months of MRI and demonstrated a symptomatic facet joint synovial cyst at the level of a previous lumbar laminectomy. Fourteen patients were enrolled, and we determined whether cyst rupture and symptom improvement were achieved after each procedure. The degrees of symptom improvement were categorized into 4: 1) symptoms improved (30% or more reduction, based on pre-procedural and post-procedural Numerical Pain Rating Scale scores), 2) symptoms not improved, 3) patient underwent surgery after injection, and 4) loss of follow-up.

RESULTS

The success rate of percutaneous synovial cyst rupture decreased with repeated procedures (62.5% for the first procedure and 0% to 33.3% for additional procedures). However, 80% of the patients had symptom improvement with the procedures, overall. The surgery rate was 14.3% in 14 patients.

CONCLUSION

For patients with post-laminectomy symptomatic lumbar facet joint synovial cysts, fluoroscopy-guided synovial cyst rupture with intra-articular steroid injection may be an effective and less invasive treatment before considering a surgical approach.

Formation of buried superconducting Mo2N by nitrogen-ion-implantation

Nitrogen ion implantation is a useful technique to put nitrogen ions into lattices. In this work, nitrogen ion implantation into epitaxial Mo films is performed to create a buried superconducting γ-Mo₂N. Atomically flat epitaxial (110) Mo films are grown on (0001) Al₂O₃. By impinging nitrogen ions, where the beam energy is fixed to 20 keV, we observe (111) γ-Mo₂N diffraction and the formation of a γ-Mo₂N layer from X-ray reflectivity. Magnetization and transport measurements clearly support a superconducting layer in the implanted film. Our strategy shows that formation of a buried superconducting layer can be achieved through ion implantation and self-annealing.

Formation of chemically distinct interfaces, including crystalline buried-superconducting Mo₂N, by low-energy nitrogen ion implantation in an epitaxial molybdenum thin film.

Reliability of pre-operative diffusion tensor imaging parameter measurements of the cervical spine in patients with cervical spondylotic myelopathy

The present study assessed test–retest and inter-observer reliability of diffusion tensor imaging (DTI) in cervical spondylotic myelopathy (CSM), as well as the agreement among measurement methods. A total 34 patients (12 men, 22 women; mean age, 58.7 [range 45–79] years) who underwent surgical decompression for CSM, with pre-operative DTI scans available, were retrospectively enrolled. Four observers independently measured fractional anisotropy (FA) values twice, using three different measurement methods. Test–retest and inter-observer reliability was assessed using intraclass correlation coefficients (ICCs). Overall, inter-observer agreements varied according to spinal cord level and the measurement methods used, and ranged from poor to excellent agreement (ICC = 0.374–0.821), with relatively less agreement for the sagittal region of interest (ROI) method. The radiology resident and neuro-radiologist group showed excellent test–retest reliability at almost every spinal cord level (ICC = 0.887–0.997), but inter-observer agreements varied from fair to good (ICC = 0.404–0.747). Despite excellent test–retest reliability of the ROI measurements, FA measurements in patients with CSM varied widely in terms of inter-observer reliability. Therefore, DTI parameter data should be interpreted carefully when applied clinically.

Association of meniscal flounce in the knee with the pattern and location of meniscal tear, concomitant ligamentous injury, amount of knee joint effusion, and flexion and rotation angles: a magnetic resonance evaluation

OBJECTIVE

To determine the association of meniscal flounce with the pattern and location of the meniscal tear, concomitant ligamentous injury, amount of knee joint effusion, and flexion and rotation angles.

MATERIALS AND METHODS

A total of 283 knees of 280 patients were retrospectively reviewed over a 9-month period. Thirty-one magnetic resonance images of patients with meniscal flounce were compared with those of age- and sex-matched control group (n = 62) without meniscal flounce. The presence of meniscal tear was evaluated and, if present, its location and pattern were recorded. The amount of joint effusion was graded, and the joint angle was measured. The Fisher's exact, Cochran-Armitage trend, and t tests were performed to compare the findings between the two groups. The decision tree analysis was employed to determine the most significant factor of meniscal flounce.

RESULTS

Meniscal flounce was present in 11.0% (31/283) of the adult population. Approximately 80.6% of meniscal flounce occurred in the torn medial menisci. The presence of meniscal flounce was significantly associated with tears at the body (p = 0.007), posterior horn (p = 0.001), and meniscocapsular junction (p = 0.002) of the medial meniscus. The decision tree analysis revealed that the posterior horn tear of the medial meniscus was the most significant predictor of meniscal flounce.

CONCLUSION

The most significant factor associated with meniscal flounce is tear at the posterior horn of the medial meniscus, followed by tear at the meniscocapsular junction.

Percutaneous Sacroplasty : Effectiveness and Long-Term Outcome Predictors

OBJECTIVE

To evaluate the effectiveness and long-term outcome predictors of percutaneous sacroplasty (PSP).

METHODS

This single-center study assessed 40 patients with sacral insufficiency fractures using the short-axis technique under C-arm flat-panel detector computed tomography (CT). Two radiologists reviewed the patients' magnetic resonance and CT images to obtain imaging findings before PSP and determine technical success, respectively. The short-term outcomes were visual analog scale score changes and opioid usage reductions. Long-term outcomes were determined using telephone interviews and the North American Spine Society (NASS) patient-satisfaction index at least one year after PSP.

RESULTS

Technical success was achieved without any significant complications in 39 patients (97.5%). Telephone interviews were possible with 12 patients and failed in 10 patients; death was confirmed in 18 patients. Fifteen patients (50%) re-visited the hospital and received conservative treatment, including spinal injections. Nine patients reported positive satisfaction (NASS patient-satisfaction index 1 or 2), while the negative satisfaction group (NASS patient-satisfaction index 3 or 4, n=3) showed a higher incidence of compression fractures at the thoracolumbar spine level (66.7% vs. 22.2%) and previous spinal injection history (66.7% vs. 33.3%). The poor response group also showed higher incidences of facet joint arthrosis (100% vs. 55.6%), central canal stenosis (100% vs. 22.2%), neural foraminal stenosis (33.3% vs. 22.2%), scoliosis (100% vs. 33.3%), and sagittal malalignment (100% vs. 44.4%).

CONCLUSION

PSP was effective for sacral insufficiency fractures and showed good long-term outcomes. Combined compression fractures in the thoracolumbar spine and degenerative lumbar pathologies could be possible poor outcome predictors.

Clinical validity of two different grading systems for lumbar central canal stenosis: Schizas and Lee classification systems

OBJECTIVE

To assess the learnability of two magnetic resonance imaging (MRI) grading systems for lumbar central canal stenosis based on inter-observer agreement and test-retest reliability of doctors with no prior knowledge of the two systems.

MATERIALS AND METHODS

Two clinical fellows, one novice radiology resident, one neurosurgeon, and one orthopedic surgeon, who were unaware of the two qualitative MRI grading systems prior to this study, acquainted themselves with the teaching files. All five observers independently assessed the LCCS grade of 70 patients using T2-weighted axial magnetic resonance images at the L2-3, L3-4, L3-4, and L5-S1 disc levels. Analysis was performed twice at an interval of two months.

RESULTS

The inter-observer agreement among all five readers was excellent and test-retest reliability was moderate to excellent for both the Schizas and Lee systems. Positive percentage agreements were found to be over 0.8 in almost all observers with relatively narrow 95% confidence limits.

CONCLUSION

Both Schizas and Lee MRI grading systems for LCCS are reliable grading systems, and can be used as a learnable method for both clinicians and radiologists.

Incidence and pattern of epidural spread during lumbar facet joint injection: a prospective study

Background

In clinical practice, we have often observed contrast material spreading into the epidural space during lumbar facet joint injection. However, the exact incidence of epidural spread and contrast pattern have not been reported.

Purpose

To evaluate the incidence and pattern of epidural spread in lumbar facet joint injection.

Material and Methods

One hundred consecutive patients (38 men, 62 women; mean age 68 years; age range 20–88 years) who underwent lumbar facet joint injection at two sites between April 2014 and June 2014 were investigated in this prospective study. Initial oblique, final anteroposterior, and lateral fluoroscopic images were obtained and evaluated for the presence of epidural spread and its contrast pattern (based on direction and extent) with the consensus of three radiologists. The relationship between epidural spread and its potential predictors was analyzed using the chi-squared test, Fisher’s exact test, and the t-test.

Results

The incidence of epidural spread during lumbar facet joint injection was 64.6% (n=64) in 99 patients and 49.5% (n=95) in 192 procedures; ventral spread occurred in 29.2% and foraminal spread in 18.8%. When epidural spread occurred, the most commonly identified distributions were unilateral (73.7%), dorsal (92.6%), and cephalad (92.6%). Epidural spread increased significantly in the caudocephalic direction ( P < 0.0001), in men (relative risk [RR]=1.478), in the adjacency of posterior fusion level (RR=1.545), in patients with spondylolisthesis (RR=1.454), and when there was no other leakage (RR=0.334).

Conclusion

Epidural spread occurred at about half the number of lumbar facet joint injections and showed a contrast pattern similar to that seen with the interlaminar approach.

Analgesic effect of ropivacaine with fentanyl in comparison with ropivacaine alone for continuous femoral nerve block after knee replacement arthroplasty: a prospective, randomized, double-blinded study

Background

The analgesic effect of perineural opioid in clinical practice are still controversial. This randomized controlled trial compared analgesic effect of ropivacaine with fentanyl or ropivacaine alone for continuous femoral nerve block following unilateral total knee arthroplasty.

Methods

Fourty patients of ASA PS Ⅰ or Ⅱ receiving total knee arthroplasty with spinal anesthesia were enlisted and randomly allocated into two groups. Group R; bolus injection of 0.375% ropivacaine, 30 ml and an infusion of 0.2% ropivacaine at 8 ml/h (n = 20). Group RF; 0.375% ropivacaine, 29 ml added with 50 μg of fentanyl as a bolus and an infusion of 0.2% ropivacaine mixed with 1 μg/ml of fentanyl at 8 ml/h (n = 20). Local anesthetic infusion via a femoral nerve catheter was started at the end of operation and continued for 48 h. Intravenous patient-controlled analgesia with hydromorphone (0.15 mg/ml, 0-1-10) were used for adjuvant analgesics. Position of catheter tip and contrast distribution, visual analogue scale of pain, hydromorphone consumption, side effects were recorded for 48 h after operation. Patient satisfaction for the pain control received were noted.

Results

The pain visual analogue scale, incidences of side effects and satisfaction were not different between the two groups (P > 0.05), but the hydromorphone usage at 48 h after operation were lower in the Group RF than in the Group R (P = 0.047).

Conclusions

The analgesic effect of ropivacaine with fentanyl for continuous femoral nerve block after knee replacement arthroplasty was not superior to that of the ropivacaine alone.

Efficacy and Safety of Flow-Diverter Therapy for Recurrent Aneurysms after Stent-Assisted Coiling

BACKGROUND AND PURPOSE

Flow-diverter treatment for previously stented aneurysms has been reported to be less effective and prone to complications. In this study, we evaluated the effectiveness and safety of flow diverters for recurrent aneurysms after stent-assisted coiling.

MATERIALS AND METHODS

Patients who underwent flow-diverter placement for recurrent aneurysms after stent-assisted coiling between March 2015 and March 2019 were recruited. Clinical and radiographic characteristics and clinical and angiographic outcomes were retrospectively evaluated.

RESULTS

Among 133 patients who underwent flow-diverter insertion, 17 (male/female ratio = 5:12; mean age, 53.8 years) were treated for recurrent aneurysms after stent placement with (n = 16) or without (n = 1) coiling. Eight patients initially presented with subarachnoid hemorrhage; 7, with headache; and 2, with visual field defects. Angiographic morphology included large/giant saccular in 12 patients, dissecting in 2, fusiform in 1, traumatic pseudoaneurysm in 1, and ruptured blood blister-like aneurysm in 1. The duration between the first treatment and flow-diverter placement ranged from 2 weeks to 15 months (median, 6 months). Flow-diverter placement was successful in all cases without any complications. All patients had favorable outcomes (mRS, 0-2), without any newly appearing symptoms. Aneurysms were followed up with conventional angiography at least once in 6-18 months. Sixteen aneurysms showed complete occlusion, and 1 aneurysm was enlarged.

CONCLUSIONS

Results from this case series investigating flow-diverter placement for recurrent aneurysms after stent-assisted coiling suggested that the procedure is safe and effective. Further study in a larger population may be warranted.

Radiofrequency ablation using injectable cooled electrode: the effects of lidocaine injection in ex vivo study

Background

Pain control is needed during radiofrequency ablation in musculoskeletal tumor. The effect of radiofrequency ablation can be modulated by lidocaine injection.

Purpose

To evaluate the effects of injectable electrodes with intralesional lidocaine injection and compare its ablation performance with that of non-injectable electrodes in ex vivo pork sirloin.

Material and Methods

Five specimen groups were used to investigate the effects of fluid injection before radiofrequency ablation using injectable and non-injectable electrodes: three injectable electrode comparison groups with 2% lidocaine (group A); 1% lidocaine (group B); 0.9% sodium chloride (group C); injectable electrode reference group without fluid (group D); and non-injectable electrode control group (group E). The injectable and non-injectable electrodes were 17-gauge electrodes each having a 1-cm active tip. Technical parameters, ablation size, and volumes were compared between the five groups.

Results

Mean energies and currents during radiofrequency ablation were significantly lower for the four injectable electrode groups compared to group E (all P < 0.005). Two transverse diameters, vertical diameter, and volumes in the four injectable electrode groups were significantly smaller than those in group E (all P < 0.05). Among the injectable electrode groups, volumes and two transverse diameters were significantly smaller in group A than in group D (all P < 0.05).

Conclusions

A slightly smaller ablation zone is obtained when lidocaine injection is performed before radiofrequency ablation using an injectable electrode compared to a non-injectable electrode.