Background: The conventional magnetic resonance imaging (MRI) grading system for foraminal stenosis (FS), known as the Lee classification, was introduced in 2010 and is widely utilized in clinical practice. Previous studies have reported that the conventional grading system for FS lacks prediction ability for surgical treatment. The purpose of this study was to develop a novel MRI grading system for lumbar FS with improved prediction ability for surgical treatment by incorporating facet effusion to indicate segmental instability. Methods: We retrospectively reviewed patients diagnosed with lumbar FS between 2011 and 2017 who had a follow-up period of at least 5 years. The FS severity was assessed using a conventional MRI grading system developed by Lee et al. We recorded whether the patient underwent surgical treatment for FS during the follow-up period and the time from the initial diagnosis to surgery. Survival analysis using a Kaplan-Meier curve and log-rank test was performed to verify the impact of FS severity on the surgical treatment. We performed additional survival analysis after modifying the grading system by incorporating the presence of excessive facet joint effusion assessed using axial MRI. We also compared the discrimination ability of the modified and conventional grading systems using Uno’s concordance index (C-index). Results: In total, 235 patients with a mean age of 63.7 years were included in this study. During the mean follow-up period of 8.1 years, 63 patients underwent surgical treatment for FS. The conventional grading system revealed no significant difference in survival between the grade 2 and 3 groups (p = 0.104). Conversely, the modified grading system revealed a significant difference in survival between the new grade 2 and 3 groups (p < 0.001). After modification, the discrimination ability, assessed using Uno’s Cindex, significantly improved from 0.69 to 0.73. Conclusions The Facet Effusion-Incorporating Grading System, which adds excessive facet joint effusion to the conventional MRI grading framework, demonstrated improved predictive value for surgical treatment and better discriminatory ability compared with the original system.

Background and Objectives: The Fractional Flow Reserve and Intravascular UltrasoundGuided Intervention Strategy for Clinical Outcomes in Patients with Intermediate Stenosis (FLAVOUR) trial demonstrated non-inferiority of fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI) compared with intravascular ultrasound (IVUS)-guided PCI. We sought to investigate the cost-effectiveness of FFR-guided PCI compared to IVUS-guided PCI in Korea. Methods: A 2-part cost-effectiveness model, composed of a short-term decision tree model and a long-term Markov model, was developed for patients who underwent PCI to treat intermediate stenosis (40% to 70% stenosis by visual estimation on coronary angiography).The lifetime healthcare costs and quality-adjusted life-years (QALYs) were estimated from the healthcare system perspective. Transition probabilities were mainly referred from the FLAVOUR trial, and healthcare costs were mainly obtained through analysis of Korean National Health Insurance claims data. Health utilities were mainly obtained from the Seattle Angina Questionnaire responses of FLAVOUR trial participants mapped to EQ-5D. Results: From the Korean healthcare system perspective, the base-case analysis showed that FFR-guided PCI was 2,451 U.S. dollar lower in lifetime healthcare costs and 0.178 higher in QALYs compared to IVUS-guided PCI. FFR-guided PCI remained more likely to be cost-effective over a wide range of willingness-to-pay thresholds in the probabilistic sensitivity analysis. Conclusions Based on the results from the FLAVOUR trial, FFR-guided PCI is projected to decrease lifetime healthcare costs and increase QALYs compared with IVUS-guided PCI in intermediate coronary lesion, and it is a dominant strategy in Korea.

Background and Objectives: The Fractional Flow Reserve and Intravascular UltrasoundGuided Intervention Strategy for Clinical Outcomes in Patients with Intermediate Stenosis (FLAVOUR) trial demonstrated non-inferiority of fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI) compared with intravascular ultrasound (IVUS)-guided PCI. We sought to investigate the cost-effectiveness of FFR-guided PCI compared to IVUS-guided PCI in Korea. Methods: A 2-part cost-effectiveness model, composed of a short-term decision tree model and a long-term Markov model, was developed for patients who underwent PCI to treat intermediate stenosis (40% to 70% stenosis by visual estimation on coronary angiography).The lifetime healthcare costs and quality-adjusted life-years (QALYs) were estimated from the healthcare system perspective. Transition probabilities were mainly referred from the FLAVOUR trial, and healthcare costs were mainly obtained through analysis of Korean National Health Insurance claims data. Health utilities were mainly obtained from the Seattle Angina Questionnaire responses of FLAVOUR trial participants mapped to EQ-5D. Results: From the Korean healthcare system perspective, the base-case analysis showed that FFR-guided PCI was 2,451 U.S. dollar lower in lifetime healthcare costs and 0.178 higher in QALYs compared to IVUS-guided PCI. FFR-guided PCI remained more likely to be cost-effective over a wide range of willingness-to-pay thresholds in the probabilistic sensitivity analysis. Conclusions Based on the results from the FLAVOUR trial, FFR-guided PCI is projected to decrease lifetime healthcare costs and increase QALYs compared with IVUS-guided PCI in intermediate coronary lesion, and it is a dominant strategy in Korea.

Background and Objectives: The Fractional Flow Reserve and Intravascular UltrasoundGuided Intervention Strategy for Clinical Outcomes in Patients with Intermediate Stenosis (FLAVOUR) trial demonstrated non-inferiority of fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI) compared with intravascular ultrasound (IVUS)-guided PCI. We sought to investigate the cost-effectiveness of FFR-guided PCI compared to IVUS-guided PCI in Korea. Methods: A 2-part cost-effectiveness model, composed of a short-term decision tree model and a long-term Markov model, was developed for patients who underwent PCI to treat intermediate stenosis (40% to 70% stenosis by visual estimation on coronary angiography).The lifetime healthcare costs and quality-adjusted life-years (QALYs) were estimated from the healthcare system perspective. Transition probabilities were mainly referred from the FLAVOUR trial, and healthcare costs were mainly obtained through analysis of Korean National Health Insurance claims data. Health utilities were mainly obtained from the Seattle Angina Questionnaire responses of FLAVOUR trial participants mapped to EQ-5D. Results: From the Korean healthcare system perspective, the base-case analysis showed that FFR-guided PCI was 2,451 U.S. dollar lower in lifetime healthcare costs and 0.178 higher in QALYs compared to IVUS-guided PCI. FFR-guided PCI remained more likely to be cost-effective over a wide range of willingness-to-pay thresholds in the probabilistic sensitivity analysis. Conclusions Based on the results from the FLAVOUR trial, FFR-guided PCI is projected to decrease lifetime healthcare costs and increase QALYs compared with IVUS-guided PCI in intermediate coronary lesion, and it is a dominant strategy in Korea.

Background and Objectives: The Fractional Flow Reserve and Intravascular UltrasoundGuided Intervention Strategy for Clinical Outcomes in Patients with Intermediate Stenosis (FLAVOUR) trial demonstrated non-inferiority of fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI) compared with intravascular ultrasound (IVUS)-guided PCI. We sought to investigate the cost-effectiveness of FFR-guided PCI compared to IVUS-guided PCI in Korea. Methods: A 2-part cost-effectiveness model, composed of a short-term decision tree model and a long-term Markov model, was developed for patients who underwent PCI to treat intermediate stenosis (40% to 70% stenosis by visual estimation on coronary angiography).The lifetime healthcare costs and quality-adjusted life-years (QALYs) were estimated from the healthcare system perspective. Transition probabilities were mainly referred from the FLAVOUR trial, and healthcare costs were mainly obtained through analysis of Korean National Health Insurance claims data. Health utilities were mainly obtained from the Seattle Angina Questionnaire responses of FLAVOUR trial participants mapped to EQ-5D. Results: From the Korean healthcare system perspective, the base-case analysis showed that FFR-guided PCI was 2,451 U.S. dollar lower in lifetime healthcare costs and 0.178 higher in QALYs compared to IVUS-guided PCI. FFR-guided PCI remained more likely to be cost-effective over a wide range of willingness-to-pay thresholds in the probabilistic sensitivity analysis. Conclusions Based on the results from the FLAVOUR trial, FFR-guided PCI is projected to decrease lifetime healthcare costs and increase QALYs compared with IVUS-guided PCI in intermediate coronary lesion, and it is a dominant strategy in Korea.

Purpose: Various materials and techniques have been explored to prevent anastomotic leakage (AL). Polyglycolic acid (PGA) sheets and cyanoacrylate (CA) glue have been investigated for their potential in wound healing and fistula closure. This study aims to assess the feasibility of PGA-CA complex (PCC) to prevent AL by developing a major leakage model in rats. Methods: After the creation of the major leakage model in the jejunum of rat, the leakage site was treated with each material individually and in combination. Rats were categorized into the control, CA, PGA, and PCC groups. Results: A total of 40 rats were included, with one animal from the CA and PGA groups having expired. Gross intraabdominal conditions showed no significant difference between the groups. Median intraluminal bursting pressure was 120.0 (range, 102.5–138.0) in the CA group and 138.0 (range, 127.0–147.0) in the PCC group (P = 0.286). Pathologic evaluation revealed fibroblast activation was significantly different in the PCC group (P = 0.025). Conclusion No significant differences were observed in the macroscopic intra-abdominal findings or intraluminal bursting pressure between the groups. The only difference in PCC group was enhanced fibroblast activation at moderate levels compare to the control group. Further research is warranted to optimize material combinations and validate efficacy in larger preclinical and clinical settings.

Isolated spinal artery aneurysms are rare vascular lesions of the spinal cord. Due to their rarity, the natural disease course and treatment guidelines have not been clearly defined. Here, we report a case of an angiography-negative isolated spinal aneurysm in the thoracic spine surgically that was treated without neurological compromise using indocyanine green (ICG) and intraoperative neurophysiological monitoring (IONM). A 52-year-old man without any prior medical history presented to the emergency room with acute lower back and bilateral leg pain accompanied by worsening voiding and difficulty defecating. Magnetic resonance imaging (MRI) of the lumbar spine showed a diffuse subarachnoid hemorrhage in the lumbar spine. The patient was initially treated conservatively with painkillers, but experienced a rapid recurrence of symptoms. A follow-up MRI scan showed subacute transformation and expansion of the subarachnoid hematoma, as well as a non-enhancing, intradural, extramedullary lesion at the T12/L1 level. Angiography did not show any remarkable findings, and surgical exploration revealed a thrombosed aneurysmal lesion. The lesion did not show ICG uptake, and temporary clipping of the caudal end of the lesion did not lead to changes in motor-evoked potential signals. A pathological examination revealed a capillary vascular structure in granulation tissue with organizing thrombi, favoring a thrombosed, granulated lesion over a vascular neoplasm. Ruptured, isolated spinal aneurysms can be especially difficult to diagnose and treat when angiography findings are negative. We report that a spinal artery aneurysm can be safely excised using intraoperative ICG and IONM.

Objective: Multilevel posterior cervical fusion (PCF) and decompression surgery is a viable treatment option for multilevel ossification of posterior longitudinal ligament (OPLL) and spondylotic myelopathy. Since OPLL is known to affect bone formation, this study aimed to examine the effect of OPLL on the incidence of pseudarthrosis following PCF in a cohort study. Methods: We conducted a retrospective cohort study of patients with PCF and laminectomy at our institution. This study included patients who underwent C3 to C6 posterior fusion surgery involving lateral mass screw fixation without anterior surgery for OPLL or spondylotic myelopathy. Fusion status was evaluated 1 year postoperatively with computed tomography. Bone mineral density (BMD) and sagittal parameters were also evaluated as potential contributing factors to the fusion rate. Results: Eighty patients were included. Pseudarthrosis was observed in 22.5% (n=18) of patients. Pseudarthrosis incidence was lower in patients with OPLL (spondylosis vs. OPLL, 33.3% vs. 12.2%; p=0.003), and a higher BMD T-score (pseudarthrosis vs. fusion, -1.9 ± 0.7 vs. -0.6 ± 1.3; p<0.01), a larger preoperative range of motion (ROM) (26.7 ± 13.3 vs. 17.6 ± 10.9; p=0.01), and a greater preoperative-to-postoperative decrease in cervical lordosis (-8.1 ± 7.9 vs. -2.7 ± 7.9; p<0.01). Pseudarthrosis was associated with worsening neck pain after surgery. Conclusion The absence of OPLL, lower BMD, larger preoperative ROM, and a greater decrease in postoperative cervical lordosis were identified as risk factors for pseudarthrosis after multiple PCF.

Objective: Spinal stenosis is a prevalent condition; however, the optimal surgical treatment for central lumbar stenosis remains controversial. This study compared the clinical outcomes and radiological parameters of 3 surgical methods: unilateral laminectomy bilateral decompression with unilateral biportal endoscopy (ULBD-UBE), conventional subtotal laminectomy (STL), and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF). Methods: This retrospective study included 86 patients, divided into ULBD-UBE (n=34), STL (n=24), and MIS-TLIF (n=28) groups. We evaluated demographics and perioperative factors and assessed clinical outcomes using the visual analogue scale (VAS), Oswestry Disability Index (ODI), and neurogenic intermittent claudication (NIC). Radiological parameters assessed included lumbar lordosis, L4S1 Cobb angle (L4S1), T12S1 Cobb angle (T12S1), increased cross-sectional dural area (CSA), dynamic angulation (DA), dynamic slip (DS), and development of postoperative instability. Results: The ULBD-UBE group showed a significantly shorter hospital stay duration and operation time and reduced blood loss than the other groups (p<0.001). ULBD-UBE group showed a trend towards greater VAS and ODI improvement at 1 month and postoperative NIC symptom relief. Radiologically, MIS-TLIF group exhibited lower postoperative DA and DS (p<0.001), indicating higher postoperative stability. Postoperative instability was lower in the ULBD-UBE group (2.9%) than in the STL group (16.7%) and similar to the MIS-TLIF group (0.0%) (p=0.028). The CSA was highest in the MIS-TLIF group (295.5%) compared to that in the other groups (ULBD-UBE, 216.3%; STL, 245.2%) (p<0.001). Conclusion Compared to other procedures, ULBD-UBE is a safe, effective, and viable surgical procedure for treating lumbar central stenosis.

Objective: We aimed to investigate the incidence of delayed-onset neurological deficits (DONDs), DOND-related reoperation rates following adult spinal deformity (ASD) surgery, and efficacy of transverse process hooks (TPHs) at the uppermost instrumented vertebra (UIV) compared to pedicle screws (PSs). Methods: We included 90 consecutive patients who underwent instrumented fusion from the sacrum to the distal thoracic spine for ASD, with a minimum follow-up of 24 months. Clinical and radiological outcomes were compared between 33 patients in the TPH group and 57 patients in the PS group, using the Scoliosis Research Society-22 Outcomes questionnaire (SRS-22), Medical Outcomes Study Questionnaire Short-Form 36 (SF-36), and various spinal sagittal parameters. Results: While absent in the TPH group, myelopathy occurred in 15.8% of the PS group, wherein 15 patients underwent reoperation. The change in the proximal junctional angle, from the pre- to postoperative assessment, was lower in the TPH group than in the PS group (0.2 vs. 6.6, p=0.002). Postoperative facet degeneration in the PS group progressed more significantly than in the TPH group (0.5 vs. 0.1, p=0.002). Surgical outcomes were comparable for both groups, except for the back visual analogue scale (3.5 vs. 4.1, p=0.010) and SRS-22 domains, including pain and satisfaction (3.3 vs. 2.9, p=0.033; 3.7 vs. 3.3, p=0.041). No intergroup difference was observed in SF-36. Conclusion Using TPHs at the UIV level can prevent DOND, and thereby prevent postoperative myelopathy that necessitates reoperation; thus, TPHs is preferable over PSs in ASD surgery.