Preoperative computed tomography-guided localization for multiple pulmonary nodules: comparison of methylene blue and coil.

BACKGROUND: Preoperative computed tomography (CT)-guided localization has been used to guide the video-assisted thoracoscopic surgery (VATS) sublobar (wedge or segmental) resection for pulmonary nodules (PNs). We aimed to assess the relative efficacy and safety of CT-guided methylene blue (MB)- and coil-based approaches to the preoperative localization of multiple PNs (MPNs). METHODS: Between January 2015 and December 2020, 31 total cases suffering from MPNs at our hospital underwent CT-guided localization and subsequent VATS resection in our hospital, of whom 15 and 16 respectively underwent MB localization (MBL) and coil localization (CL). The clinical effectiveness and complication rates were compared between 2 groups. RESULTS: The PN- and patient-based technical success rates in the MBL group were both 100%, whereas in the CL group they were 97.2% (35/36) and 93.8% (15/16), respectively, with no substantial discrepancies between groups. Patients in the MBL group illustrated a substantially shorter CT-guided localization duration compared with the CL group (18 min vs. 29.5 min, P < 0.001). Pneumothorax rates (P = 1.000) and lung hemorrhage (P = 1.000) were comparable in both groups. In the MBL and CL groups, the median interval between localization and VATS was 1 h and 15.5 h, respectively (P < 0.001). One-stage VATS sublobar resection of the target nodules was successfully performed in all patients from both groups. CONCLUSION: Both CT-guided MBL and CL can be readily and safely utilized for preoperative localization in individuals who had MPNs, with MBL being correlated with a shorter localization duration compared with CL.

Cigarette Smoking Preferentially Affects Intracranial Vessels in Young Males: A Propensity-Score Matching Analysis.

PURPOSE: Cigarette smoking (CS) is one of the major risk factors of cerebral atherosclerotic disease, however, its level of contribution to extracranial and intracranial atherosclerotic stenosis (ECAS and ICAS) was not fully revealed yet. The purpose of our study was to assess the association of CS to cerebral atherosclerosis along with other risk factors. MATERIALS AND METHODS: All consecutive patients who were angiographically confirmed with severe symptomatic cerebral atherosclerotic disease between January 2002 and December 2012 were included in this study. Multivariate logistic regression analyses were performed to identify risk factors for ECAS and ICAS. Thereafter, CS group were compared to non-CS group in the entire study population and in a propensity-score matched population with two different age-subgroups. RESULTS: Of 1709 enrolled patients, 794 (46.5%) had extracranial (EC) lesions and the other 915 (53.5%) had intracranial (IC) lesions. CS group had more EC lesions (55.8% vs. 35.3%, P<0.001) whereas young age group (<50 years) had more IC lesion (84.5% vs. 47.6%, P<0.001). In multivariate analysis, seven variables including CS, male, old age, coronary heart disease, higher erythrocyte sedimentation rate, multiple lesions, and anterior lesion were independently associated with ECAS. In the propensity-score matched CS group had significant more EC lesion compared to non-CS group (65.7% vs. 47.9%) only in the old age subgroup. CONCLUSION: In contrast to a significant association between CS and severe symptomatic ECAS shown in old population, young patients did not show this association and showed relatively higher preference of ICAS.

Clinical Characteristics and Treatment Outcomes of Spinal Arteriovenous Malformations.

PURPOSE: Spinal arteriovenous malformations (SAVMs) are rare events. This study evaluated initial clinical presentations and treatment outcomes of SAVMs. METHODS: In this study, 91 consecutive patients with SAVM between January 1993 and November 2014 were evaluated. Initial clinical presentations, radiological findings, treatment results, and follow-up outcomes were evaluated according to disease type and treatment modalities. Patient status was scored using the modified Rankin scale (mRS) and Aminoff-Logue Disability scale (ALS). RESULTS: Of the SAVM patients 69 % were male and 31 % were female with a mean age of 49 years (range 11-82 years). At the time of initial imaging evaluation, myelopathy was the most common finding with main complaints of gait disturbance (69 out of 91, 76 %), sensory disturbances (61/91, 67 %), and bowel or bladder symptoms (51/91, 56 %). Among the 80 patients who received treatment 56 (62 %) underwent endovascular embolization and 24 (26 %) underwent surgery. Complete obliteration was achieved in 47 patients (84 %) after endovascular embolization and in 18 (75 %) after surgical ligation. At the time of final follow-up 67 patients (84 %) showed improvement of more than 1 point on the mRS, while 69 (86 %) showed significant improvement on the ALS after treatment. CONCLUSION: The SAVMs presented with diverse neurological deficits, including myelopathy. Endovascular or surgical treatment of SAVMs can result in good clinical outcomes in most patients.

Induced-Wedge Technique to Improve Liquid Embolic Agent Penetration into Spinal Dural Arteriovenous Fistula.

OBJECTIVE: To promote embolization of spinal dural arteriovenous fistula (SDAVF) with a small long tortuous feeder that may impede successful application of an embolic agent. METHODS: An induced-wedge technique was developed in which blood flow was blocked by coiling at the proximal part of the microcatheter for secure injection of N-butyl cyanoacrylate. We used this technique in 11 patients with SDAVF (male/female ratio, 8:3): 7 thoracic, 2 lumbar, 1 sacral, and 1 cervical. Clinical outcome was evaluated by the Aminoff-Logue Disability Scale. RESULTS: Penetration of embolic agent through the fistula into the vein was complete (n = 5), nearly complete (no penetration of embolic agent into the vein but no residual fistula on 3 adjacent selective angiograms; n = 4), or partial (embolization with a small residual filling of the draining vein; n = 2). All patients improved neurologically during follow-up (median, 18 months; range, 7-37 months) and achieved complete recovery. Of the 2 patients who obtained partial obliteration, one showed disappearance of the residual lesion on angiography 21 months later and the other achieved complete results after repeat embolization. CONCLUSIONS: The induced-wedge technique can improve SDAVF embolization by providing better penetration of the liquid embolic agent to the fistula and vein.

Outpatient Day-care Neuroangiography and Neurointervention of Unruptured Intracranial Aneurysms.

PURPOSE: Day-care management of unruptured intracranial aneurysms can shorten hospital stay, reduce medical cost and improve outcome. We present the process, outcome and duration of hospital stay for the management of unruptured intracranial aneurysms via a neurointervention clinic in a single center during the past four years. MATERIALS AND METHODS: We analyzed 403 patients who were referred to Neurointervention Clinic at Asan Medical Center for aneurysm evaluation between January 1, 2011 and December 31, 2014. There were 141 (41%) diagnostic catheter angiographies, 202 (59%) neurointerventional procedures and 2 (0.6%) neurointerventional procedures followed by operation. We analyzed the process, outcome of angiography or neurointervention, and duration of hospital stay. RESULTS: There was no aneurysm in 58 patients who were reported as having an aneurysm in MRA or CTA (14 %). Among 345 patients with aneurysm, there were 283 patients with a single aneurysm (82%) and 62 patients with multiple aneurysms (n=62, 18%). Aneurysm coiling was performed in 202 patients (59%), surgical clipping in 14 patients (4%), coiling followed by clipping in 2 patients (0.6%) and no intervention was required in 127 patients (37%). The hospital stay for diagnostic angiography was less than 6 hours and the mean duration of hospital stay was 2.1 days for neurointervention. There were 4 procedure-related adverse events (2%) including 3 minor and 1 major ischemic strokes. CONCLUSION: Our study revealed that day-care management of unruptured intracranial aneurysms could be performed without an additional risk. It could enable rapid patient flow, shorten hospital stay and thus reduce hospital costs.

Virtual stenting of intracranial aneurysms: application of hemodynamic modification analysis.

BACKGROUND: Practical application of hemodynamic modification analysis based on computational fluid dynamics (CFD) in intracranial aneurysms is still under study. PURPOSE: To determine the clinical applicability of virtual stenting of aneurysms by comparing the simulated results with clinical outcome of real stenting. MATERIAL AND METHODS: Three-dimensional (3D) digital subtraction angiography (DSA) images were imported to a dedicated integrated prototypic CFD platform (Siemens Healthcare GmbH) which allows all necessary steps of 3D models for CFD analysis. The results of CFD simulation with virtual implantation of a stent can be visualized in the same platform for qualitative comparisons on a color-coded volume visualization window. Five small intracranial aneurysms with and without virtual stenting were analyzed and assessed on a qualitative level. Expert rating were performed for evaluating the simulated results, and comparing those to the long-term follow-up outcomes of real stenting. RESULTS: CFD simulation after virtual stenting was feasible in five differently located aneurysms and corresponded to the long-term changes of stented aneurysms by showing alteration in flow pattern. There was no significant difference (P = 0.5) between the simulated hemodynamic changes after virtual stenting and the angiographic changes after stenting in four aneurysms except one. There was good agreement regarding the assessment of the changes by two raters (kappa = 0.657). CONCLUSION: CFD analysis using patient-specific virtual stenting of the CFD platform may be used as a simple and less time-consuming test tool predicting the involution of aneurysms after stent placement by analyzing the vector visualization of the flow changes.

Immediate and long-term outcomes of endovascular treatment for massive hemoptysis.

BACKGROUND: The aim of this study was to evaluate the immediate and long-term outcomes of endovascular treatment for massive hemoptysis and to identify the factors influencing outcome. METHODS: A total of 147 patients who underwent transarterial embolization for massive hemoptysis between 2001 and 2012 were retrospectively evaluated. All patients (93 males and 54 females, ranging in age from 28 to 76 years) had active massive bleeding and underwent bronchial artery embolization (BAE) and/or non-bronchial artery embolization (NBAE). Angiography result, endovascular techniques, embolized materials and complications were recorded. RESULTS: Complete cessation of massive hemoptysis was achieved in 126/147 patients (85.7%) and failed in 21/147 patients (14.3%) within 24 hours. The etiology of hemoptysis was as follows: bronchiectasis (49.7%), tuberculosis (24.5%), artery malformation (14.3%), lung carcinoma (9.5%) and idiopathic hemoptysis (2.0%). In many patients of tuberculosis and artery malformation, abnormal bronchial and nonbronchial systemic artery-pulmonary circulation shunts were usually found. During a mean follow-up period of 18 months (range from 1 day to 63 months), hemoptysis was controlled in 117(79.6%), ineffective and recurred in 30 (20.4%) and 14 (9.5%) required repeat embolization. A better success rate of 90.4% was obtained in the bronchiectasis group. The worse results were seen in the lung carcinoma group with 42.9%. The tuberculosis and artery malformation groups also demonstrated good results. Transient quadriplegia of major complication was recorded in 1/147 (0.7%). Minor complications such as chest pain, dysphagia and fever were recorded in 45/147 (30.6%). CONCLUSIONS: BAE and NBAE are safe and effective procedure for treatment for massive hemoptysis, with low recurrence and complication rates. Abnormal bronchial and nonbronchial systemic artery-pulmonary circulation shunts were usually found in many patients of tuberculosis and artery malformation. The better success rate was obtained by the bronchiectasis group, and ineffectiveness and high recurrence rate is associated with lung carcinoma.

Does a Low-wall Coverage Stent Have a Flow Diverting Effect in Small Aneurysms?

BACKBROUND AND PURPOSE: The flow diverting effect of a low-wall coverage stent remains controversial. We evaluted patients who underwent stenting for small aneurysms with a low but potential risk of growth and reviewed related literature. MATERIALS AND METHODS: We evaluated 9 small aneurysms among 19 unruptured intracranial aneurysms from eight patients who underwent stenting. The patients had unexplainable severe headache (n = 8), aneurysm originating from the anterior choroidal artery (n = 3), potential growth or rupture risks including hypertension (n = 5), and multiple aneurysms (n = 6). Stents with a relatively low-wall coverage ratio (8-10%) were used. Clinical and angiographic outcomes were assessed. RESULTS: One (n = 8) or two stents (n = 1) were used without any procedural difficulties or complications. Although no immediate changes of aneurysm morphology were observed, aneurysms decreased in size (n = 8) when examined by DSA (n = 8) or MRA (n = 1) during a median 28.9-month follow-up. There were no adverse events, including thromboembolism, aneurysm rupture, or stent movement during a median 31.9-month clinical follow-up (range: 17-69 months). CONCLUSION: Although a variable degree of aneurysm size decrease may not prevent further growth or rupture of small aneurysms, stenting with a low-wall coverage ratio may have some advantageous hemodynamic effect. Flow modification of stent architecture vs. aneurysm characteristics, including size and location, on long-term outcome, requires further clarification.

A Study Design to Evaluate Association between Smoking and Intracranial Atherosclerotic Stenosis.

PURPOSE: Smoking is a well known risk factor for stroke. The cerebral arteries may be uniquely susceptible to the atherosclerotic effects of smoking, such that it has a different risk profile for stroke compared with other atherosclerosis risk factors. It remains uncertain whether smoking is associated specifically with intracranial (IC) or extracranial (EC) atherosclerotic cerebrovascular disease. The aim of this study design will be to evaluate the association between smoking and severe IC stenosis, adjusting for other atherosclerosis risk factors, particularly age distribution. STUDY DESIGN: This is a retrospective cohort study design. Participants are patients (n=1714) with severe atherosclerotic stenosis undergoing cerebral catheter angiography because of stroke or transient ischaemic attack. All atherosclerotic steno-occlusive lesions are described in terms of location (anterior versus posterior circulation, IC versus EC, or intradural versus extradural). The atherosclerotic or stroke risk factors for analysis include age, gender, smoking history, number of lesions (single versus multiple), cardiac disease, diabetes mellitus, hypertension, family history, dyslipidemia, history of previous stroke, alcohol intake, metabolic syndrome and body mass index. Statistical analysis includes univariate analysis followed by multivariate logistic regression. The relationship between IC atherosclerotic stenosis and smoking will be assessed. Differences in risk factor distribution is analysed according to age at intervals of 10 years. Significant risk factors associated with IC atherosclerotic stenosis will also be assessed by multivariate logistic regression analysis. SUMMARY: This is an analytical study design that intends to measure the association between IC or EC atherosclerotic stenosis and smoking and other risk factors. We anticipate that it will have the power to detect any relationship between smoking and IC atherosclerotic lesions especially in younger patients.