Tag: statistics

NMR Biomed. 2025 Jun;38(6):e70042. doi: 10.1002/nbm.70042.

ABSTRACT

The pathological changes in deep medullary veins (DMVs) have been reported in various diseases. However, accurate modeling and quantification of DMVs remain challenging. We aim to propose and assess an automated approach for modeling and quantifying DMVs at 7 Tesla (7 T) MRI. A multi-echo-input Res-Net was developed for vascular segmentation, and a minimum path loss function was used for modeling and quantifying the geometric parameter of DMVs. Twenty-one patients diagnosed as subcortical vascular dementia (SVaD) and 20 condition matched controls were included in this study. The amplitude and phase images of gradient echo with five echoes were acquired at 7 T. Ten GRE images were manually labeled by two neurologists and compared with the results obtained by our proposed method. Independent samples t test and Pearson correlation were used for statistical analysis in our study, and p value < 0.05 was considered significant. No significant offset was found in centerlines obtained by human labeling and our algorithm (p = 0.734). The length difference between the proposed method and manual labeling was smaller than the error between different clinicians (p < 0.001). Patients with SVaD exhibited fewer DMVs (mean difference = -60.710 ± 21.810, p = 0.011) and higher curvature (mean difference = 0.12 ± 0.022, p < 0.0001), corresponding to their higher Vascular Dementia Assessment Scale-Cog (VaDAS-Cog) scores (mean difference = 4.332 ± 1.992, p = 0.036) and lower Mini-Mental State Examination (MMSE) (mean difference = -3.071 ± 1.443, p = 0.047). The MMSE scores were positively correlated with the numbers of DMVs (r = 0.437, p = 0.037) and were negatively correlated with the curvature (r = -0.426, p = 0.042). In summary, we proposed a novel framework for automated quantifying the morphologic parameters of DMVs. These characteristics of DMVs are expected to help the research and diagnosis of cerebral small vessel diseases with DMV lesions.

PMID:40242874 | DOI:10.1002/nbm.70042

Stroke. 2025 Apr 17. doi: 10.1161/STROKEAHA.124.050171. Online ahead of print.

ABSTRACT

BACKGROUND: Blood-brain barrier (BBB) leakage measured with dynamic susceptibility contrast-enhanced magnetic resonance imaging (MRI) has been associated with hemorrhagic transformation in acute ischemic stroke. However, the influence of prethrombolysis BBB leakage on infarct growth has not been studied. Therefore, we aimed to characterize BBB integrity according to tissue state at admission and tissue fate on follow-up MRI.

METHODS: This is a post hoc analysis of the WAKE-UP trial (Efficacy and Safety of MRI-Based Thrombolysis in Wake-Up Stroke). Ischemic cores were segmented on diffusion-weighted imaging at baseline and on fluid-attenuated inversion recovery images at follow-up (22-36 hours). Dynamic susceptibility contrast-enhanced-MRI provided penumbra masks (time to maximum of the tissue residue function >6 s minus ischemic core) and BBB leakage (extraction fraction [EF], Z scored) maps via automated analysis. EF was averaged within the ischemic core, total penumbra, 2 penumbra subtypes (salvaged/infarcted penumbra), and normal tissue. Adjusted linear mixed-effects models tested for differences between tissue types and associations of EF with clinical/imaging outcomes. Complementary voxel-wise analyses were performed.

RESULTS: Of 503 patients enrolled in the trial, 165 with suitable dynamic susceptibility contrast-enhanced-MRI data were included in this analysis (mean age 66 years, 38% women, median National Institutes of Health Stroke Scale score of 6; 53% receiving alteplase). EF was significantly increased in the ischemic core and penumbra relative to normally perfused tissue, while differences between total penumbra and ischemic core were statistically nonsignificant. Infarcted penumbra exhibited higher EF than salvaged penumbra, even after adjusting for hypoperfusion severity (P<0.001, n=79 with baseline penumbral tissue and follow-up MRI). Voxel-wise analyses showed a significant association between EF and voxel-level infarction in the placebo group only. EF did not predict hemorrhagic transformation or functional outcomes.

CONCLUSIONS: Penumbral BBB leakage may identify tissue at increased risk of infarction. Larger, prospective studies are needed to determine the clinical relevance of BBB leakage as an imaging marker of tissue fate.

REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01525290. Unique identifier: 2011-005906-32.

PMID:40242873 | DOI:10.1161/STROKEAHA.124.050171

Allergy. 2025 Apr 17. doi: 10.1111/all.16558. Online ahead of print.

ABSTRACT

BACKGROUND: Symptom monitoring can improve adherence to daily medication. However, controlled clinical trials on multi-modular allergy apps and their various functions have been difficult to implement. The objective of this study was to assess the clinical benefit of an allergy app with varying numbers of functions in reducing symptoms and improving quality of (QoL) life in grass pollen allergic individuals. The secondary objective was to develop a symptom forecast based on patient-derived and environmental data.

METHODS: We performed a stratified, controlled intervention study (May-August 2023) with grass pollen allergic participants (N = 167) in Augsburg, Germany. Participants were divided into three groups, each receiving the same allergy app, but with increasing numbers of functions.

PRIMARY ENDPOINT: rhinitis-related QoL; Secondary endpoints: symptom scores, relevant behavior, self-reported usefulness of the app, symptom forecast.

RESULTS: Rhinitis-related QoL was increased after the intervention, with no statistical inter-group differences. However, participants with access to the full app version, including a pollen forecast, took more medication and reported lower symptoms and social activity impairment than participants with access to a reduced-function app. Using an XGBoost multiclass classification model, we achieved promising results for predicting nasal (accuracy: 0.79; F1-score: 0.78) and ocular (accuracy: 0.82; F1-score: 0.76) symptom levels and derived feature importance using SHAP as a guidance for future approaches.

CONCLUSION: Our allergy app with its high-performance pollen forecast, symptom diary, and general allergy-related information provides a clinical benefit for allergy sufferers. Reliable symptom forecasts may be created given high-quality and high-resolution data.

PMID:40242867 | DOI:10.1111/all.16558

ASEAN J Psychiatry. 2024 Jul 12;2024. doi: 10.54615/2231-7805.47358.

ABSTRACT

BACKGROUND: Amphetamine and other substances induced psychotic disorder and associated suicidal risk among hospitalized US veterans is not clear.

AIMS: To understand the demographic profile, substance use trends, psychotic disorders and suicide attempts in veterans hospitalized with acute Mental Health Conditions (MHC).

METHODS: Veterans Affairs Informatics and Computing Infrastructure Database (ICD) and codes were used to identify veterans hospitalized with MHC diagnosis between 1999 and 2022. Laboratory records used to determine types of substances used hospitalization frequency, all-cause mortality, suicide attempts and suicide outcomes. SAS was used for statistical analysis.

RESULTS: Among veterans with MHC, psychosis, manic-bipolar and PTSD were common diagnosis. Psychosis was comparatively less among males above 50 years of age, but prevalent among Hispanics. In general, substances use was significantly higher, and amphetamines were most used, followed by cannabis codeine, morphine, cocaine, barbiturates, fentanyl, and PCP among veterans with MHC. Amphetamine induced psychotic disorder persisted in 22.28% and other substance induced psychotic disorder persisted in 77.72% of veterans hospitalized with MHC. Psychosis was associated with higher rates of hospitalization, suicide attempts, and suicide death.

CONCLUSIONS: Among US Veterans with MHC, amphetamine was most used substance associated with higher rates of psychotic disorders, hospitalization, suicide attempts, and death.

PMID:40242831 | PMC:PMC11997896 | DOI:10.54615/2231-7805.47358

J Spine Surg. 2025 Mar 24;11(1):65-73. doi: 10.21037/jss-24-75. Epub 2025 Feb 27.

ABSTRACT

BACKGROUND: Patient-specific spine rods (PSSRs) are custom-designed pre-operatively to align with individual spinopelvic parameters, aiming to optimize post-operative alignment. While effective in correcting adult spinal deformities, their utility in degenerative lumbar fusions remains relatively understudied. This study seeks to assess the outcomes of PSSR utilization in degenerative lumbar fusions by comparing them to a previously published cohort by Leveque et al. in 2018. Through this analysis, we aim to contribute to the understanding of PSSR efficacy and its potential role in improving surgical outcomes in degenerative lumbar conditions.

METHODS: Fifty patients who underwent primary lumbar fusion with PSSRs were included, excluding those with prior lumbar fusion or significant deformities. The study cohort was compared to a historical cohort using conventional rods. Radiographic outcomes were evaluated over a 2-year period, with follow-ups at 6 weeks, 6 months, 1 year, and 2 years postoperatively. Pre-operative and post-operative measurements of pelvic incidence (PI) and lumbar lordosis (LL) were used to assess changes in changes in PI-LL alignment. Statistical analyses included one-way analysis of variance (ANOVA) tests and one/two sample t-tests.

RESULTS: Patients undergoing fusion PSSRs demonstrated a greater degree of change in pre-operative to post-operative PI-LL alignment compared to non-PSSR patients (-4.2° vs. -0.1°, P<0.001). Among the PSSR group, post-operative analysis revealed that 37 patients (74%) were categorized as preserved, indicating maintenance of PI-LL alignment within a predefined range. Additionally, nine patients (18%) were classified as restored, representing an improvement in PI-LL alignment post-operatively. Conversely, two patients (4%) were categorized as not corrected and worsened, indicating no significant change or deterioration in PI-LL alignment post-operatively, respectively. Comparison between the PSSR and non-PSSR groups showed higher restored spinopelvic parameters after surgery in the PSSR group compared to the non-PSSR group (18% vs. 8.7%, P=0.05). Conversely, fewer patients in the PSSR group had not corrected parameters compared to the non-PSSR group (4% vs. 21.3%, P<0.01). These findings suggest that fusion with PSSRs was associated with greater improvement in PI-LL alignment post-operatively and a higher likelihood of achieving restored spinopelvic parameters compared to fusion without PSSRs.

CONCLUSIONS: PSSRs demonstrate significant improvement in spinopelvic parameters, particularly in reducing PI-LL mismatch, in degenerative lumbar fusion surgery. This improvement suggests a potential for enhanced patient outcomes. Follow-up assessments indicate that these improvements are sustained over a 2-year period. However, our findings underscore the need for further research to validate these results on a larger scale and over the long term. Larger-scale studies are necessary to confirm long-term benefits and should aim to explore the specific mechanisms by which PSSRs contribute to improved outcomes and investigate optimal strategies for incorporating PSSRs into clinical practice.

PMID:40242816 | PMC:PMC11998052 | DOI:10.21037/jss-24-75

J Spine Surg. 2025 Mar 24;11(1):65-73. doi: 10.21037/jss-24-75. Epub 2025 Feb 27.

ABSTRACT

BACKGROUND: Patient-specific spine rods (PSSRs) are custom-designed pre-operatively to align with individual spinopelvic parameters, aiming to optimize post-operative alignment. While effective in correcting adult spinal deformities, their utility in degenerative lumbar fusions remains relatively understudied. This study seeks to assess the outcomes of PSSR utilization in degenerative lumbar fusions by comparing them to a previously published cohort by Leveque et al. in 2018. Through this analysis, we aim to contribute to the understanding of PSSR efficacy and its potential role in improving surgical outcomes in degenerative lumbar conditions.

METHODS: Fifty patients who underwent primary lumbar fusion with PSSRs were included, excluding those with prior lumbar fusion or significant deformities. The study cohort was compared to a historical cohort using conventional rods. Radiographic outcomes were evaluated over a 2-year period, with follow-ups at 6 weeks, 6 months, 1 year, and 2 years postoperatively. Pre-operative and post-operative measurements of pelvic incidence (PI) and lumbar lordosis (LL) were used to assess changes in changes in PI-LL alignment. Statistical analyses included one-way analysis of variance (ANOVA) tests and one/two sample t-tests.

RESULTS: Patients undergoing fusion PSSRs demonstrated a greater degree of change in pre-operative to post-operative PI-LL alignment compared to non-PSSR patients (-4.2° vs. -0.1°, P<0.001). Among the PSSR group, post-operative analysis revealed that 37 patients (74%) were categorized as preserved, indicating maintenance of PI-LL alignment within a predefined range. Additionally, nine patients (18%) were classified as restored, representing an improvement in PI-LL alignment post-operatively. Conversely, two patients (4%) were categorized as not corrected and worsened, indicating no significant change or deterioration in PI-LL alignment post-operatively, respectively. Comparison between the PSSR and non-PSSR groups showed higher restored spinopelvic parameters after surgery in the PSSR group compared to the non-PSSR group (18% vs. 8.7%, P=0.05). Conversely, fewer patients in the PSSR group had not corrected parameters compared to the non-PSSR group (4% vs. 21.3%, P<0.01). These findings suggest that fusion with PSSRs was associated with greater improvement in PI-LL alignment post-operatively and a higher likelihood of achieving restored spinopelvic parameters compared to fusion without PSSRs.

CONCLUSIONS: PSSRs demonstrate significant improvement in spinopelvic parameters, particularly in reducing PI-LL mismatch, in degenerative lumbar fusion surgery. This improvement suggests a potential for enhanced patient outcomes. Follow-up assessments indicate that these improvements are sustained over a 2-year period. However, our findings underscore the need for further research to validate these results on a larger scale and over the long term. Larger-scale studies are necessary to confirm long-term benefits and should aim to explore the specific mechanisms by which PSSRs contribute to improved outcomes and investigate optimal strategies for incorporating PSSRs into clinical practice.

PMID:40242816 | PMC:PMC11998052 | DOI:10.21037/jss-24-75

J Spine Surg. 2025 Mar 24;11(1):88-95. doi: 10.21037/jss-24-99. Epub 2025 Mar 7.

ABSTRACT

BACKGROUND: Considering that implant backout is a recognized mode of failure, evaluating the pullout strength is critical for assessing anchoring efficacy. The Sacrix^® fully threaded screw (TS) was designed specifically for Less Exposure Spine Surgery (LESS) to reduce incision size, surgical time, and blood loss, using two implants for sacroiliac joint (SIJ) fixation. This study compares the Sacrix^® design with the SI-Bone iFuse non-threaded triangular titanium implant (TTI) design, which is widely regarded as the industry standard, and represents the first comparative biomechanical pullout strength study of these implant designs currently used in SIJ fusions.

METHODS: We conducted mechanical static axial pullout tests on three 7.0 mm × 45 mm iFuse non-threaded TTIs and six 8.0 mm × 40 mm Sacrix^® fully TS embedded in polyurethane foam blocks. An INSTRON 8874 Bi-Axial Tabletop Servohydraulic Dynamic Testing System was used to perform the tests by applying a 2.5 kN axial load.

RESULTS: The effective surface areas of the iFuse non-threaded TTI and Sacrix^® fully threaded TS were comparable, measuring 294.15 and 289.81 mm², respectively. The TS exhibited a significantly higher mean static axial pullout strength of 814.90 N [standard deviation (SD), ±99.428 N] compared to the TTI 200.14 N (SD, ±14.428 N). Statistical analyses, including Welch’s t-test and Mann-Whitney U test, revealed significant differences in pullout strength between the two implants (P<0.05). Variance analysis confirmed the differences in pullout strength variances between the implants (P=0.040), suggesting that the variability in pullout strength was distinct for each implant.

CONCLUSIONS: The Sacrix^® fully threaded TS demonstrated a threefold increase in pullout strength compared with the SI-Bone iFuse non-threaded TTI, suggesting that future SIJ fusion designs should favor threaded over non-threaded implants for improved anchoring capability.

PMID:40242812 | PMC:PMC11998034 | DOI:10.21037/jss-24-99

J Spine Surg. 2025 Mar 24;11(1):88-95. doi: 10.21037/jss-24-99. Epub 2025 Mar 7.

ABSTRACT

BACKGROUND: Considering that implant backout is a recognized mode of failure, evaluating the pullout strength is critical for assessing anchoring efficacy. The Sacrix^® fully threaded screw (TS) was designed specifically for Less Exposure Spine Surgery (LESS) to reduce incision size, surgical time, and blood loss, using two implants for sacroiliac joint (SIJ) fixation. This study compares the Sacrix^® design with the SI-Bone iFuse non-threaded triangular titanium implant (TTI) design, which is widely regarded as the industry standard, and represents the first comparative biomechanical pullout strength study of these implant designs currently used in SIJ fusions.

METHODS: We conducted mechanical static axial pullout tests on three 7.0 mm × 45 mm iFuse non-threaded TTIs and six 8.0 mm × 40 mm Sacrix^® fully TS embedded in polyurethane foam blocks. An INSTRON 8874 Bi-Axial Tabletop Servohydraulic Dynamic Testing System was used to perform the tests by applying a 2.5 kN axial load.

RESULTS: The effective surface areas of the iFuse non-threaded TTI and Sacrix^® fully threaded TS were comparable, measuring 294.15 and 289.81 mm², respectively. The TS exhibited a significantly higher mean static axial pullout strength of 814.90 N [standard deviation (SD), ±99.428 N] compared to the TTI 200.14 N (SD, ±14.428 N). Statistical analyses, including Welch’s t-test and Mann-Whitney U test, revealed significant differences in pullout strength between the two implants (P<0.05). Variance analysis confirmed the differences in pullout strength variances between the implants (P=0.040), suggesting that the variability in pullout strength was distinct for each implant.

CONCLUSIONS: The Sacrix^® fully threaded TS demonstrated a threefold increase in pullout strength compared with the SI-Bone iFuse non-threaded TTI, suggesting that future SIJ fusion designs should favor threaded over non-threaded implants for improved anchoring capability.

PMID:40242812 | PMC:PMC11998034 | DOI:10.21037/jss-24-99

J Spine Surg. 2025 Mar 24;11(1):24-32. doi: 10.21037/jss-24-116. Epub 2025 Mar 17.

ABSTRACT

BACKGROUND: Endoscopic spine surgery (ESS) has evolved as a new minimally invasive surgical (MIS) approach to the lumbar spine. ESS allows smaller incisions, less paraspinal muscle splitting and surgical trauma compared to conventional open and MIS approaches. We present the first non-inferiority comparison of ESS and open approaches to treat lumbar radiculopathy in an Australian cohort. The aim of this study is to assess if ESS is non-inferior to open approaches for the treatment of lumbar radiculopathy in post operative outcomes of pain and disability scores, in order to address the paucity in data for outcomes of ESS in Australian patients.

METHODS: In this retrospective cohort study, routinely collected prospective data were collated from consecutive patients who had single level endoscopic discectomies for radiculopathy by two surgeons at a single institution between December 2020 and October 2022. Data collected included Visual Analogue Scores for Back (VAS-B) and leg (VAS-L) pain as well as Oswestry Disability Index (ODI) scores, length of stay (LOS) and complication rates. These were compared to data from consecutive patients who underwent open discectomies from August 2020 to September 2022 by the same surgeons at other private hospitals where the endoscope was unavailable, otherwise deemed suitable for either approach, allowing direct comparison of consecutive patients operated on for comparable pathologies differentiated only by equipment availability.

RESULTS: Analysis included 92 endoscopic and 97 open cases. Non-inferiority was established at 6-week with median VAS-L (1.0 vs. 1.8, between group difference -0.5, P<0.001), VAS-B (1.0 vs. 1.0, between group difference -0.3, P=0.002) and ODI (18 vs. 20, between group difference -0.5, P<0.001) and 6-month for ODI (14 vs. 20, between group difference -1.6, P<0.001). Six-month median VAS-L and VAS-B was identical between groups (1.0 and 2.0), however this was not statistically significant. LOS was lower in ESS (LOS <24 h 93% vs. 78%, P=0.005). Reoperation rates were similar (10% vs. 7%, P=0.73). There were fewer complications in the endoscopic cohort than in the open cohort (5% vs. 6%), however this was not statistically significant.

CONCLUSIONS: ESS is non-inferior to open decompression for the management of lumbar radiculopathy up to 6 months. LOS was also found to be lower in ESS. There were fewer complications with ESS however this was not statistically significant.

PMID:40242811 | PMC:PMC11998043 | DOI:10.21037/jss-24-116

J Spine Surg. 2025 Mar 24;11(1):24-32. doi: 10.21037/jss-24-116. Epub 2025 Mar 17.

ABSTRACT

BACKGROUND: Endoscopic spine surgery (ESS) has evolved as a new minimally invasive surgical (MIS) approach to the lumbar spine. ESS allows smaller incisions, less paraspinal muscle splitting and surgical trauma compared to conventional open and MIS approaches. We present the first non-inferiority comparison of ESS and open approaches to treat lumbar radiculopathy in an Australian cohort. The aim of this study is to assess if ESS is non-inferior to open approaches for the treatment of lumbar radiculopathy in post operative outcomes of pain and disability scores, in order to address the paucity in data for outcomes of ESS in Australian patients.

METHODS: In this retrospective cohort study, routinely collected prospective data were collated from consecutive patients who had single level endoscopic discectomies for radiculopathy by two surgeons at a single institution between December 2020 and October 2022. Data collected included Visual Analogue Scores for Back (VAS-B) and leg (VAS-L) pain as well as Oswestry Disability Index (ODI) scores, length of stay (LOS) and complication rates. These were compared to data from consecutive patients who underwent open discectomies from August 2020 to September 2022 by the same surgeons at other private hospitals where the endoscope was unavailable, otherwise deemed suitable for either approach, allowing direct comparison of consecutive patients operated on for comparable pathologies differentiated only by equipment availability.

RESULTS: Analysis included 92 endoscopic and 97 open cases. Non-inferiority was established at 6-week with median VAS-L (1.0 vs. 1.8, between group difference -0.5, P<0.001), VAS-B (1.0 vs. 1.0, between group difference -0.3, P=0.002) and ODI (18 vs. 20, between group difference -0.5, P<0.001) and 6-month for ODI (14 vs. 20, between group difference -1.6, P<0.001). Six-month median VAS-L and VAS-B was identical between groups (1.0 and 2.0), however this was not statistically significant. LOS was lower in ESS (LOS <24 h 93% vs. 78%, P=0.005). Reoperation rates were similar (10% vs. 7%, P=0.73). There were fewer complications in the endoscopic cohort than in the open cohort (5% vs. 6%), however this was not statistically significant.

CONCLUSIONS: ESS is non-inferior to open decompression for the management of lumbar radiculopathy up to 6 months. LOS was also found to be lower in ESS. There were fewer complications with ESS however this was not statistically significant.

PMID:40242811 | PMC:PMC11998043 | DOI:10.21037/jss-24-116