V advancement eversion flap for fingertip injury: Preventing ischemia and hook-nail deformity.

Introduction: Traumatic fingertip amputation is the most common type of upper extremity injuries. The V-Y advancement flap is a reliable method for reconstructing fingertip defects, but it is associated with complications such as hook-nail deformity and suture site ischemia. Here, we describe our modifications to V-Y advancement flap technique, termed as "V advancement eversion flap" and review the outcomes of this procedure in 21 patients with fingertip amputation. Methods: This was a retrospective review of 21 consecutive patients with fingertip injury who were treated surgically using the V advancement eversion flap technique at a single trauma center between 2006 and 2019. We analyzed the age, injury location and mechanism, Allen classification, injury geometry, and objective and subjective clinical outcomes. Results: Twenty-three fingertip amputations with defect sizes greater than 1.0 cm2 from the tip to lunula were included in this study. The mean age of the patients was 43.6 years (range, 24-65 years). The average follow-up period was 20 months (range, 12-37 months). The average wound healing time (apparent epithelization) was 29.4 days (range, 14-41 days). At the final follow-up, all flaps had healed uneventfully without noticeable hook-nail deformity. In the static two-point discrimination test, the mean value was 4.61 mm in the injured finger. Patient ratings of the outcomes were "excellent" in 18 and "good" in 5 cases. Conclusion: The V advancement eversion flap technique, when properly designed and executed in fingertip amputation cases, can minimize morbidity and result in successful wound healing without flap necrosis and hook-nail deformity.

Photophore-Anchored Molecular Switch for High-Performance Nonvolatile Organic Memory Transistor.

Over the past decade, molecular-switch-embedded memory devices, particularly field-effect transistors (FETs), have gained significant interest. Molecular switches are integrated to regulate the resistance or current levels in FETs. Despite substantial efforts, realizing large memory window with a long retention time, a critical factor in memory device functionality, remains a challenge. This is due to the inability of an isomeric state of a molecular switch to serve as a stable deep trap state within the semiconductor layer. Herein, the study addresses this limitation by introducing chemical bonding between molecular switch and conjugated polymeric semiconductor, facilitating closed isomer of diarylethene (DAE) to operate as a morphologically stable deep trap state. Azide- and diazirine-anchored DAEs are synthesized, which form chemical bonds to the polymer through photocrosslinking, thereby implementing permanent and controllable trapping states nearby conjugated backbone of polymer semiconductor. Consequently, when diazirine-anchored DAE is blended with F8T2 and subjected to photocrosslinking, the resulting organic FETs exhibit remarkable memory performance, including a memory window of 22 V with a retention time over 106 s, a high photoprogrammable on/off ratio over 103, and a high operational stability over 100 photocycles. Further, photophore-anchored DAEs can achieve precise patterning, which enables meticulous control over the semiconductor layer structure.

Unveiling the inhibition mechanism of Clostridioides difficile by Bifidobacterium longum via multiomics approach.

Antibiotic-induced gut microbiota disruption constitutes a major risk factor for Clostridioides difficile infection (CDI). Further, antibiotic therapy, which is the standard treatment option for CDI, exacerbates gut microbiota imbalance, thereby causing high recurrent CDI incidence. Consequently, probiotic-based CDI treatment has emerged as a long-term management and preventive option. However, the mechanisms underlying the therapeutic effects of probiotics for CDI remain uninvestigated, thereby creating a knowledge gap that needs to be addressed. To fill this gap, we used a multiomics approach to holistically investigate the mechanisms underlying the therapeutic effects of probiotics for CDI at a molecular level. We first screened Bifidobacterium longum owing to its inhibitory effect on C. difficile growth, then observed the physiological changes associated with the inhibition of C. difficile growth and toxin production via a multiomics approach. Regarding the mechanism underlying C. difficile growth inhibition, we detected a decrease in intracellular adenosine triphosphate (ATP) synthesis due to B. longum-produced lactate and a subsequent decrease in (deoxy)ribonucleoside triphosphate synthesis. Via the differential regulation of proteins involved in translation and protein quality control, we identified B. longum-induced proteinaceous stress. Finally, we found that B. longum suppressed the toxin production of C. difficile by replenishing proline consumed by it. Overall, the findings of the present study expand our understanding of the mechanisms by which probiotics inhibit C. difficile growth and contribute to the development of live biotherapeutic products based on molecular mechanisms for treating CDI.

Necessity of induction agent modification for old age kidney transplant recipients.

Background: Immunosenescence gradually deteriorates the function of the immune system, making elderly patients susceptible to infection, while reducing rejection of organ transplants. Therefore, age-adaptive immunosuppression is necessary in the elderly. We evaluated clinical outcomes such as rejection and infection rate when using basiliximab and rabbit anti-thymocyte globulin (r-ATG) as induction agents in elderly and young organ transplant recipients. Methods: We retrospectively reviewed patients who underwent kidney transplantation (KT) between June 2011 and April 2019. We enrolled 704 adult KT patients and classified the patients into groups according to patient age. We compared the outcomes of infection and biopsy-proven acute rejection (BPAR) according to the type of induction agent (basiliximab and r-ATG [4.5 mg/kg]). Results: The patient group included 520 recipients (74.6%) in the younger recipient group and 179 recipients (25.4%) in the older recipient group. When r-ATG was used as an induction agent, BPAR within 6 months occurred less (p = 0.03); however, infections within 6 months were higher in older recipients. Deaths due to infection were more common in older recipients (p = 0.003). Conclusion: It may be necessary to use less intensive induction therapy for older recipients, of which dose reduction of r-ATG is one option.

Upper thigh skeletal muscle index predicts outcomes in liver transplant recipients.

Purpose: The skeletal muscle index (SMI) at the L3 level is widely used to diagnose sarcopenia. The upper thigh (UT) also reflects changes in whole-body muscle mass, but no study has examined this using the UT to diagnose sarcopenia in liver transplantation (LT). This study aimed to determine an optimal cut-off value for UT-SMI and investigate how sarcopenia diagnosed by UT-SMI correlates with outcomes in LT recipients. Methods: In this retrospective study of 332 LT patients from 2018 to 2020, we investigated the association between sarcopenia diagnosed by UT-SMI and patient outcomes after LT. Results: The cut-off values for UT-SMI were 38.3 cm2/m2 for females (area under the curve [AUC], 0.927; P < 0.001) and 46.7 cm2/m2 for males (AUC, 0.898; P < 0.001). The prevalence of sarcopenia diagnosed by UT-SMI was 33.4% in our cohort. Patient and graft survival rates in the UT-SMI sarcopenia group were significantly poorer than those in the UT-SMI non-sarcopenia group (P < 0.001 and P < 0.001). UT-SMI was an independent prognostic factor for patient survival (hazard ratio [HR], 2.182; 95% confidence interval [CI], 1.183-4.025; P = 0.012) and graft survival (HR, 2.227; 95% CI, 1.054-4704; P = 0.036) in our multivariable Cox analysis. Conclusion: We confirmed that sarcopenia diagnosed by UT-SMI is associated with outcomes in LT recipients. In addition, UT-SMI was identified as an independent prognostic factor for patient survival and graft survival. Therefore, UT-SMI could be a good option for CT-based evaluations of sarcopenia in LT recipients.

Graft-recipient-weight ratio and lowered immunosuppression is important for the success of adult liver retransplantation.

This study analyzed the risk of liver retransplantation and factors related to better outcome. Adult liver transplantations performed during 1996-2021 were included. Comparison between first transplantation and retransplantation were performed. Among retransplantation cases, comparison between whole liver and partial liver graft was performed. Multivariable Cox analyses for analyzing risk factors for primary graft and overall patient survival were performed for the entire cohort as well as the subgroup of patients with retransplantation. A total 2237 transplantations from 2135 adults were included and 103 cases were retransplantation. A total of 44 cases (42.7%) were related to acute graft dysfunction while 59 cases (57.3%) were related to subacute or chronic graft dysfunction. Retransplantation was related poor primary graft (HR 3.439, CI 2.230-5.304, P < 0.001) and overall patient survival. (HR 2.905, CI 2.089-4.040, P < 0.001) Among retransplantations, mean serum FK506 trough level ≥ 9 ng/mL was related to poor primary graft (HR 3.692, CI 1.288-10.587, P = 0.015) and overall patient survival. (HR 2.935, CI 1.195-7.211, P = 0.019) Graft-recipient-weight ratio under 1.0% was related to poor overall patient survival in retransplantations. (HR 3.668, CI 1.150-11.698, P = 0.028). Retransplantation can be complicated with poor graft and patient survival compared to first transplantation, especially when the graft size is relatively small. Lowering the FK506 trough level during the first month can be beneficial for outcome.

Multiomics analysis reveals the biological effects of live Roseburia intestinalis as a high-butyrate-producing bacterium in human intestinal epithelial cells.

Butyrate-producing bacteria play a key role in human health, and recent studies have triggered interest in their development as next-generation probiotics. However, there remains limited knowledge not only on the identification of high-butyrate-producing bacteria in the human gut but also in the metabolic capacities for prebiotic carbohydrates and their interaction with the host. Herein, it was discovered that Roseburia intestinalis produces higher levels of butyrate and digests a wider variety of prebiotic polysaccharide structures compared with other human major butyrate-producing bacteria (Eubacterium rectale, Faecalibacterium prausnitzii, and Roseburia hominis). Moreover, R. intestinalis extracts upregulated the mRNA expression of tight junction proteins (TJP1, OCLN, and CLDN3) in human intestinal epithelial cells more than other butyrate-producing bacteria. R. intestinalis was cultured with human intestinal epithelial cells in the mimetic intestinal host-microbe interaction coculture system to explore the health-promoting effects using multiomics approaches. Consequently, it was discovered that live R. intestinalis only enhances purine metabolism and the oxidative pathway, increasing adenosine triphosphate levels in human intestinal epithelial cells, but that heat-killed bacteria had no effect. Therefore, this study proposes that R. intestinalis has potentially high value as a next-generation probiotic to promote host intestinal health.

Hepatic venous territory mapping in living donor liver transplantation using right liver graft: an objective parameter for venous reconstruction.

Purpose: This study evaluated the clinical implication of hepatic venous territory mapping in living donor liver transplantation. Methods: Living donor liver transplantations performed using right graft since 2017 were included. Hepatic venous volume mapping was started in 2019. Risk factors for graft failure and overall survival were analyzed. Analysis for factors related to occlusion of reconstructed vein was performed. Results: Among 445 patients included, 213 underwent hepatic venous mapping. Hepatic venous mapping itself was not a significant factor for graft (hazard ratio [HR], 0.958; 95% confidence interval [CI], 0.441-2.082; P = 0.913) and overall survival (HR, 0.627; 95% CI, 0.315-1.247; P = 0.183). Inferior hepatic vein occlusion was a significant risk factor for both graft survival (HR, 8.795; 95% CI, 1.628-47.523; P = 0.012) and overall survival (HR, 11.13; 95% CI, 2.460-50.300; P = 0.002). In a subgroup with middle hepatic vein reconstruction, occlusion was a significant risk factor for overall survival (HR, 3.289; 95% CI, 1.304-8.296; P = 0.012). In patients with middle hepatic vein reconstruction whose venous territory volumes were measured, right anterior volume of ≥300 cm3 was protective for vein occlusion (OR, 0.317; 95% CI, 0.152-0.662; P = 0.002). In patients with V5 reconstruction, V5 volume of ≥150 cm3 was protective for vein occlusion (OR, 0.253; 95% CI, 0.087-0.734; P = 0.011). Conclusion: Inferior and middle hepatic vein reconstruction has significant impact on clinical outcome. Hepatic venous territory mapping can provide an objective measure for successful reconstruction of venous branches.

Improved recurrence-free survival in patients with HCC with post-transplant plasma exchange.

Total plasma exchange (TPE) can play a role in cancer treatment by eliminating immune checkpoint inhibitors. This study investigated whether TPE improved oncological outcomes in patients with HCC who underwent ABO-incompatible living donor liver transplantation (LT). The study included 152 patients who underwent ABO-incompatible living donor LT for HCC between 2010 and 2021 at Samsung Medical Center. Overall survival was analyzed using the Kaplan-Meier curve, whereas HCC-specific recurrence-free survival (RFS) was analyzed using the cumulative incidence curve after propensity score matching. Cox regression and competing risks subdistribution hazard models were used to identify the risk factors associated with overall survival and HCC-specific RFS, respectively. The propensity score matching resulted in 54 matched pairs, grouped according to whether they underwent postoperative TPE [post-transplant TPE(+)] or not [post-transplant TPE(-)]. The 5-year HCC-specific RFS cumulative incidence was superior in the post-transplant TPE (+) group [12.5% (95% CI: 3.1%-21.9%)] compared with the post-transplant TPE(-) group [38.1% (95% CI: 24.4%-51.8%), p = 0.005]. In subgroup analysis for patients with microvascular invasion and those beyond the Milan criteria, the post-transplant TPE(+) group showed significantly superior HCC-specific survival. The multivariable analysis also showed that postoperative TPE had a protective effect on HCC-specific RFS (HR = 0.26, 95% CI: 0.10-0.64, p = 0.004) and that the more post-transplant TPE was performed, the better RFS was observed (HR = 0.71, 95% CI: 0.55-0.93, p = 0.012). Post-transplant TPE was found to improve RFS after ABO-incompatible living donor LT for HCC, particularly in advanced cases with microvascular invasion and beyond Milan criteria. These findings suggest that TPE may have a potential role in improving oncological outcomes in patients with HCC undergoing LT.

Investigation of metabolic crosstalk between host and pathogenic Clostridioides difficile via multiomics approaches.

Clostridioides difficile is a gram-positive anaerobic bacterium that causes antibiotic-associated infections in the gut. C. difficile infection develops in the intestine of a host with an imbalance of the intestinal microbiota and, in severe cases, can lead to toxic megacolon, intestinal perforation, and even death. Despite its severity and importance, however, the lack of a model to understand host-pathogen interactions and the lack of research results on host cell effects and response mechanisms under C. difficile infection remain limited. Here, we developed an in vitro anaerobic-aerobic C. difficile infection model that enables direct interaction between human gut epithelial cells and C. difficile through the Mimetic Intestinal Host-Microbe Interaction Coculture System. Additionally, an integrative multiomics approach was applied to investigate the biological changes and response mechanisms of host cells caused by C. difficile in the early stage of infection. The C. difficile infection model was validated through the induction of disaggregation of the actin filaments and disruption of the intestinal epithelial barrier as the toxin-mediated phenotypes following infection progression. In addition, an upregulation of stress-induced chaperones and an increase in the ubiquitin proteasomal pathway were identified in response to protein stress that occurred in the early stage of infection, and downregulation of proteins contained in the electron transfer chain and ATP synthase was observed. It has been demonstrated that host cell energy metabolism is inhibited through the glycolysis of Caco-2 cells and the reduction of metabolites belonging to the TCA cycle. Taken together, our C. difficile infection model suggests a new biological response pathway in the host cell induced by C. difficile during the early stage of infection at the molecular level under anaerobic-aerobic conditions. Therefore, this study has the potential to be applied to the development of future therapeutics through basic metabolic studies of C. difficile infection.

An Integrative Multiomics Approach to Characterize Prebiotic Inulin Effects on Faecalibacterium prausnitzii.

Faecalibacterium prausnitzii, a major commensal bacterium in the human gut, is well known for its anti-inflammatory effects, which improve host intestinal health. Although several studies have reported that inulin, a well-known prebiotic, increases the abundance of F. prausnitzii in the intestine, the mechanism underlying this effect remains unclear. In this study, we applied liquid chromatography tandem mass spectrometry (LC-MS/MS)-based multiomics approaches to identify biological and enzymatic mechanisms of F. prausnitzii involved in the selective digestion of inulin. First, to determine the preference for dietary carbohydrates, we compared the growth of F. prausnitzii in several carbon sources and observed selective growth in inulin. In addition, an LC-MS/MS-based intracellular proteomic and metabolic profiling was performed to determine the quantitative changes in specific proteins and metabolites of F. prausnitzii when grown on inulin. Interestingly, proteomic analysis revealed that the putative proteins involved in inulin-type fructan utilization by F. prausnitzii, particularly ß-fructosidase and amylosucrase were upregulated in the presence of inulin. To investigate the function of these proteins, we overexpressed bfrA and ams, genes encoding ß-fructosidase and amylosucrase, respectively, in Escherichia coli, and observed their ability to degrade fructan. In addition, the enzyme activity assay demonstrated that intracellular fructan hydrolases degrade the inulin-type fructans taken up by fructan ATP-binding cassette transporters. Furthermore, we showed that the fructose uptake activity of F. prausnitzii was enhanced by the fructose phosphotransferase system transporter when inulin was used as a carbon source. Intracellular metabolomic analysis indicated that F. prausnitzii could use fructose, the product of inulin-type fructan degradation, as an energy source for inulin utilization. Taken together, this study provided molecular insights regarding the metabolism of F. prauznitzii for inulin, which stimulates the growth and activity of the beneficial bacterium in the intestine.

Two-Week Protocol Biopsy in Renal Allograft: Feasibility, Safety, and Outcomes.

BACKGROUND: Protocol biopsy in renal allograft helps to early detect subclinical rejection (SCR) in patients who have no abnormal clinical and laboratory findings. Still, there are rare reports about the techniques and outcomes of two-week protocol biopsy. The aim of this study was to assess two-week protocol biopsy regarding the technical feasibility, procedure safety, and clinical outcomes. METHODS: A total of 894 protocol biopsies were performed in adult recipients between 2012 and 2019. Two-week and one-year protocol biopsies were guided with ultrasound in 842 and 399 patients by one of four radiologists with wide range of biopsy experience, respectively. These protocol biopsies were compared in terms of feasibility and safety. Standard references were clinico-laboratory findings and biopsy examinations. RESULTS: The median period of two-week and one-year protocol biopsies were 12 days (10-20 days) and 383 days (302-420 days), respectively. All protocol biopsies were technically successful and there was no difference between radiologists regarding technical success and complications (p = 0.453). Major complication (Clavien-Dindo grading II-IV) rates of two-week and one-year protocol biopsies were 0.3% (3/842) and 0.2% (1/399), respectively (p = 1.000). However, univariate analysis demonstrated that platelet count < 100 K/mL and blood urea nitrogen ≥ 40 mg/dL were associated with major complications in two-week protocol biopsy. The SCRs of these protocol biopsies were 15.4% (130/842) and 33.6% (134/399), respectively (p < 0.001). CONCLUSION: Two-week protocol biopsy is technically feasible and safe. It contributes to early detecting a substantial number of SCRs. Prior to the biopsy, platelet count and blood urea nitrogen should be carefully checked to predict major complications.

An integrative multiomics approach to characterize anti-adipogenic and anti-lipogenic effects of Akkermansia muciniphila in adipocytes.

The cellular components of Akkermansia muciniphila are considered potential biotherapeutics for the improvement of obesity, diabetes, and metabolic diseases. However, the molecular-based mechanism of A. muciniphila for treatment of obesity, which can provide important evidence for human research, has rarely been explored. Here, we applied integrative multiomics approaches to investigate the underlying molecular mechanism involved in obesity treatment by A. muciniphila. First, the treatment with a cell lysate of A. muciniphila reduced lipid accumulation in 3T3-L1 cells and downregulated the mRNA expression of proteins involved in adipogenesis and lipogenesis. Our proteomic results revealed that A. muciniphila decreased the expression of proteins involved in fat cell differentiation, fatty acid metabolism, and energy metabolism in adipocytes. Moreover, A. muciniphila significantly reduced the level of metabolites related to glycolysis, the TCA cycle, and ATP in adipocytes. Interestingly, serine protease inhibitor A3 (SERPINA3) homologs were overexpressed in the 3T3-L1 cells treated with A. muciniphila. Small interfering RNA (siRNA) transfection demonstrated that A. muciniphila upregulates SERPINA3G expression and inhibits lipogenesis in adipocytes. Taken together, our multiomics-based approaches enabled to uncover the molecular mechanism of A. muciniphila for treatment of obesity and provide potent anti-lipogenic agents.

Safety and effectiveness of kidney transplantation using a donation after brain death donor with acute kidney injury: a retrospective cohort study.

The use of kidneys from donation after brain death (DBD) donors with acute kidney injury (AKI) is a strategy to expand the donor pool. The aim of this study was to evaluate how kidney transplantation (KT) from a donor with AKI affects long-term graft survival in various situations. All patients who underwent KT from DBD donors between June 2003 and April 2016 were retrospectively reviewed. The KDIGO (Kidney Disease: Improving Global Outcomes) criteria were used to classify donor AKI. The cohort included 376 donors (no AKI group, n = 117 [31.1%]; AKI group n = 259 [68.9%]). Death-censored graft survival was similar according to the presence of AKI, AKI severity, and the AKI trend (p = 0.929, p = 0.077, and p = 0.658, respectively). Patients whose donors had AKI who received using low dose (1.5 mg/kg for three days) rabbit anti-thymocyte globulin (r-ATG) as the induction agent had significantly superior death-censored graft survival compared with patients in that group who received basiliximab (p = 0.039). AKI in DBD donors did not affect long-term death-censored graft survival. Low-dose r-ATG may be considered as an induction immunosuppression in recipients receiving kidneys with AKI because it showed better graft survival than basiliximab.

Development of an in vitro coculture device for the investigation of host-microbe interactions via integrative multiomics approaches.

The commensal gut bacterium Akkermansia muciniphila is well known as a promising probiotic candidate that improves host health and prevents diseases. However, the biological interaction of A. muciniphila with human gut epithelial cells has rarely been explored for use in biotherapeutics. Here, we developed an in vitro device that simulates the gut epithelium to elucidate the biological effects of living A. muciniphila via multiomics analysis: the Mimetic Intestinal Host-Microbe Interaction Coculture System (MIMICS). We demonstrated that both human intestinal epithelial cells (Caco-2) and the anaerobic bacterium A. muciniphila can remain viable for 12 h after coculture in the MIMICS. The transcriptomic and proteomic changes (cell-cell junctions, immune responses, and mucin secretion) in gut epithelial cells treated with A. muciniphila closely correspond with those reported in previous in vivo studies. In addition, our proteomic and metabolomic results revealed that A. muciniphila activates glucose and lipid metabolism in gut epithelial cells, leading to an increase in ATP production. This study suggests that A. muciniphila improves metabolism for ATP production in gut epithelial cells and that the MIMICS may be an effective general tool for evaluating the effects of anaerobic bacteria on gut epithelial cells.

Clinical effectiveness of liraglutide on weight loss in South Koreans: First real-world retrospective data on Saxenda in Asia.

ABSTRACT: Among Asian countries, South Korea was the first to approve liraglutide as a treatment for obesity. Thus, the clinical effectiveness of liraglutide has not been studied in Asian populations.In this study, we retrospectively analyzed obese patients [body mass index (BMI) >27 kg/m2] who were treated with liraglutide between March 2018 and March 2019 in a single clinic. Weight, BMI, HbA1c, and clinical data were collected before liraglutide treatment. Changes in body weight and composition and their relationships with clinical variables were examined at re-prescription dates within 30, 60, 90, and 180 days.A total of 169 subjects were studied. The average age was 41.5 years, and 42% of the subjects were male. The average weight was 85.2 kg, and the average BMI was 30.8 kg/m2. Weight reduction was significant (-5.5 ±â€Š3.4 kg, 30 days: -3.2 ±â€Š1.8 kg, 60 days: -4.5 ±â€Š2.3 kg, 90 days: -6.3 ±â€Š2.6 kg, 180 days: -7.8 ±â€Š3.5 kg) during the follow-up period and increased with longer treatment time (P < .001). The percentages of subjects that showed ≥ 5% and ≥ 10% body weight reduction were 62.1% and 17.2%, respectively. In the body composition analysis, skeletal muscle weight loss was -3.56 ±â€Š29.7%, which was significantly smaller than fat weight loss of -11.06 ±â€Š10.4% (P = .03). Weight loss was not significantly related to age, sex, baseline BMI, baseline HbA1c, smoking status, alcohol consumption, coffee intake.In conclusion, Liraglutide treatment led to meaningful weight loss in South Korean patients, and fat mass reduction was prominent during treatment. Furthermore, liraglutide showed greater clinical effectiveness with longer treatment time.

The Natural History of High-Grade Partial Thickness Rotator Cuff Tears: The Conversion Rate to Full Thickness Tears and Affecting Factors.

BACKGROUND: Information regarding the progression of high-grade partial thickness rotator cuff tears (PTRCTs) is scarce. We aimed to assess the clinical outcome and the conversion rate to full thickness tears in patients with high-grade PTRCTs who underwent nonoperative treatment and to determine the factors associated with tear progression. METHODS: A total of 52 patients with high-grade PTRCTs, which were detected by magnetic resonance imaging or ultrasonography (USG), were treated conservatively between 2010 and 2017. They were followed up with USG at 6- to 12-month intervals for a mean of 34 months (range, 12-105 months). The average patient age was 57 years (range, 34-70 years), and 34 patients were women. Age, sex, body mass index, arm dominance, symptom duration, subscapularis tendon involvement, tear location, and trauma history were compared between patients with and without conversion to full thickness tears. RESULTS: A substantial percentage of high-grade PTRCTs progressed to full thickness tears (16/52, 30.8%). According to Kaplan-Meier analysis, the full thickness conversion rate was 30.8% at 3 years and 64% at 4 years. The full thickness conversion rate was higher in patients with subscapularis tendon involvement (p = 0.012). CONCLUSIONS: A considerably large proportion of high-grade PTRCTs progressed to full thickness tears. Therefore, regular monitoring of tear progression should be considered after conservative treatment of high-grade PTRCTs, particularly in patients with subscapularis tendon involvement.

New quantified measurement of fatty infiltration of the rotator cuff muscles using magnetic resonance imaging.

BACKGROUND: The degree of fatty infiltration of the rotator cuff muscle is typically evaluated using the Goutallier-Fuchs grading system, but its consistency remains controversial. This study aimed to evaluate a new quantified measurement of fatty infiltration based on three-dimensionally reconstructed volumetric data obtained from magnetic resonance images of non-pathologic shoulders using open-source software. METHODS: Fourteen shoulder 3-T magnetic resonance images (8 men, 6 women) without lesions obtained between 2010 and 2017 were analysed. Slicer version 4.6.2 was used to semi-automatically reconstruct the three-dimensional volumetric data from T2 sagittal oblique images and to differentiate fat tissue from rotator cuff muscle using the difference in signal intensity. RESULTS: The cutoff value for dividing muscle and fat was 508.9. The inter-class and intra-class correlations of each rotator cuff muscle and fat tissue were >0.9 (all P < 0.001). The mean muscle volume of the supraspinatus, infraspinatus, teres minor, and subscapularis were 15.2, 20.9, 13.3, and 29.7 mL, respectively. The muscle volume of the men was greater than that of the women (all P < 0.001), and the fat infiltration ratio was positively correlated with body mass index (all P < 0.05). CONCLUSIONS: The semi-automated quantified measurement of fatty infiltration of the rotator cuff muscles using magnetic resonance imaging and Slicer software presented excellent consistency. This technique could be an alternative measurement to complement the weak consistency of the Goutallier-Fuchs grading system. However, to reduce the error of measurement, this study evaluated non-pathologic shoulders. Therefore, further study using magnetic resonance imaging of pathologic shoulders is necessary for actual clinical application. LEVEL OF EVIDENCE: Level IV, case series, diagnostic study.