Woosung Lee’s research while affiliated with Ewha Womans University and other places

Recurrent aneurysms are a major cause of re-aneurysmal subarachnoid hemorrhage (aSAH), but information on long-term clip durability and predictors is insufficient. This study aimed to present the incidence rate of > 10 years and investigate predictors of a recurrent aneurysm in aSAH survivors. We included 1601 patients admitted with aSAH and treated by microsurgical clipping between January 1993 and May 2010. Of these patients, 435 aSAH survivors were included in this study (27.2%). The total follow-up time was 5680.9 patient-years, and the overall incidence rate was 0.77% per patient-year. The cumulative probability of recurrence without residua and regrowth of the neck remnant was 0.7% and 13.9% at 10 years, respectively. Neck remnant (hazard ratio [HR], 10.311; 95% confidence interval [CI], 5.233–20.313) and alcohol consumption over the moderate amount (HR, 3.166; 95% CI, 1.313–7.637) were independent risk factors of recurrent aneurysm. Current smoking and multiplicity at initial aSAH presentation were significant factors in a univariate analysis. Furthermore, de novo intracranial aneurysms (DNIAs) were more common in the recurrent group than in the non-recurrent group (40.9% vs. 11.5%, P < 0.001). In the present study, we noted the long-term clip durability and predictor of recurrence after microsurgical clipping. These findings can assist clinicians in identifying patients at a high risk of recurrent aneurysm and recommending selective long-term surveillance after microsurgical clipping.

Objective To evaluate the outcomes of flow-diverting device (FDD) treatment for large vertebral artery dissecting aneurysms (VADAs).Methods This retrospective study evaluated 12 patients with 12 VADAs who were treated using FDD between 2013 and 2020. Clinical and radiographic data, including procedure-related complications and clinical outcomes assessed using the modified Rankin Scale (mRS) at the time of the last follow-up, were collected and reviewed.ResultsAll 12 patients had unruptured aneurysms. There were 3 (25%) female and 9 (75%) male patients, and the mean patient age was 54.6 years. The mean size of the aneurysm was 15.9 ± 4.8 mm. The mean follow-up duration was 15.8 months. Single FDD without additional coils was used in all patients. One patient underwent second-line treatment with FDD for recurrence of large VADA after stent-assisted coiling. Immediate follow-up angiography after placement of the FDD demonstrated intra-aneurysmal contrast stasis. There were 2 (17%) patients who had peri-procedural stroke. Angiography at the 6-month follow-up in 10 patients showed favorable occlusion (OKM grade C3 + D). A total of 11 (92%) patients had good clinical outcome (modified Rankin Scale ≤ 2) at the last follow-up. No re-treatment or delayed aneurysm rupture occurred during the follow-up period.Conclusions Reconstructive technique with FDD is a feasible and effective modality for the treatment of large VADAs, showing favorable occlusion rate and clinical outcome.

OBJECTIVE Risk factors of ventriculostomy-associated infection (VAI) reported in the literature are variable due to heterogeneity of external ventricular drainage (EVD) procedures and management. This study aimed to assess the rate of VAI and its risk factors. METHODS The authors retrospectively reviewed the medical records of patients older than 18 years who received EVD catheterizations between January 2015 and December 2020. RESULTS Among 243 patients with 355 catheters, twenty-three VAIs were identified, yielding VIA rates of 9.5% per patient and 6.5% per catheter. VAI was associated with a longer total EVD duration (29.2 days vs. 15.8 days, P < 0.001), a longer procedural time (72 minutes vs. 40 minutes, P < 0.001), intraoperative ventriculostomy (39.1% vs. 9.1%, P < 0.001), craniotomy (87.0% vs. 60.9%, P = 0.014), and other systemic infections (30.4% vs. 8.2%, P = 0.004). On multivariate analysis, a longer total EVD duration (OR = 1.086, P < 0.001), intraoperative ventriculostomy (OR = 6.119, P = 0.001), and other systemic infections (OR = 4.620, P = 0.015) were associated with VAI. There was no statistical difference between the VAI rates of patients with and without prophylactic EVD exchanges at mean 12.6 days (7.1% vs. 2.2%, P = 0.401). CONCLUSIONS Intraoperative ventriculostomy was independently associated with VAI. Prophylactic EVD exchange at 12.6 days did not lower VAI rate.

Objective: Metallic susceptibility artifact due to implanted clips is a major limitation of using 3D time-of-flight magnetic resonance angiography (TOF-MRA) for follow-up imaging of clipped aneurysms (CAs). The purpose of this study was to compare pointwise encoding time reduction with radial acquisition (PETRA) subtraction-based MRA with TOF-MRA in terms of imaging quality and visibility of clip-adjacent arteries for use in follow-up imaging of CAs. Methods: Sixty-two patients with 73 CAs were included retrospectively in this comparative study. All patients underwent PETRA-MRA after TOF-MRA performed simultaneously with 3-T MRI between September 2019 and March 2020. Two neuroradiologists independently compared images obtained with both MRA modalities to evaluate overall image quality using a 4-point scale and visibility of the parent artery and branching vessels near the clips using a 3-point scale. Subgroup analysis was performed according to the number of clips (less-clipped [1-2 clips] vs more-clipped [≥ 3 clips] aneurysms). The ability to detect aneurysm recurrence was also assessed. Results: Compared with TOF-MRA, PETRA-MRA showed acceptable image quality (score of 3.97 ± 0.18 for TOF-MRA vs 3.73 ± 0.53 for PETRA-MRA) and had greater visibility of the adjacent vessels near the CAs (score of 1.25 ± 0.59 for TOF-MRA vs 2.27 ± 0.75 for PETRA-MRA, p < 0.0001). PETRA-MRA had greater visibility of vessels adjacent to less-clipped aneurysms (score of 2.39 ± 0.75 for less-clipped aneurysms vs 2.09 ± 0.72 for more-clipped aneurysms, p = 0.014). Of 73 CAs, aneurysm recurrence in 4 cases was detected using PETRA-MRA. Conclusions: This study demonstrated that PETRA-MRA is superior to TOF-MRA for visualizing adjacent vessels near clips and can be an advantageous alternative to TOF-MRA for follow-up imaging of CAs.

Background: The survival rate of aneurysmal subarachnoid hemorrhage (aSAH) has gradually increased, leading to more clinical cases of de novo intracranial aneurysms (DNIAs). Objective: To identify the characteristics of patients with DNIA growth or rupture. Methods: We included 1601 patients with aSAH treated by clipping from January 1993 to May 2010. According to the inclusion and exclusion criteria, 233 patients had no DNIAs, and 63 patients had 77 DNIAs. We assessed the incidence rate of DNIAs and risk factors for DNIA formation. After dichotomizing the DNIA group into the heed (patients with DNIA rupture or growth) and stable groups (patients without DNIA growth), we assessed the risk factors for DNIA growth or rupture. Results: The total follow-up period was 4427.9 patient-years. The incidence rate per patient-year was 1.42%. Age ≤50 yr, family history of aneurysm, and multiplicity at initial aSAH were significant risk factors for DNIA formation. Multivariate regression analysis revealed that female sex (odds ratio [OR], 5.566; 95% confidence interval [CI], 1.241-24.952), duration from initial aSAH to DNIA detection <120 mo (OR, 5.043; 95% CI, 1.362-18.668), multiplicity at initial aSAH (OR, 4.859; 95% CI, 1.207-19.563), and maximum DNIA diameter ≥4 mm (OR, 11.104; 95% CI, 2.337-52.772) were significant risk factors for DNIA growth or rupture. Conclusion: DNIAs had a higher incidence rate than expected. Taking into account the presented incidence rate and risk factors, long-term surveillance in aSAH survivors for more than a decade may be worth considering, at least on a case-by-case basis.

Purpose: The coronavirus disease 2019 (COVID-19) pandemic disrupted the emergency medical care system worldwide. We analyzed the changes in the management of intracerebral hemorrhage (ICH) and compared the pre-COVID-19 and COVID-19 eras. Materials and methods: From March to October of the COVID-19 era (2020), 83 consecutive patients with ICH were admitted to four comprehensive stroke centers. We retrospectively reviewed the data of patients and compared the treatment workflow metrics, treatment modalities, and clinical outcomes with the patients admitted during the same period of pre-COVID-19 era (2017-2019). Results: Three hundred thirty-eight patients (83 in COVID-19 era and 255 in pre-COVID-19 era) were included in this study. Symptom onset/detection-to-door time [COVID-19; 56.0 min (34.0-106.0), pre-COVID-19; 40.0 min (27.0-98.0), p=0.016] and median door to-intensive treatment time differed between the two groups [COVID-19; 349.0 min (177.0-560.0), pre-COVID-19; 184.0 min (134.0-271.0), p<0.001]. Hematoma expansion was detected more significantly in the COVID-19 era (39.8% vs. 22.1%, p=0.002). At 3-month follow-up, clinical outcomes of patients were worse in the COVID-19 era (Good modified Rankin Scale; 33.7% in COVID19, 46.7% in pre-COVID-19, p=0.039). Conclusion: During the COVID-19 era, delays in management of ICH was associated with hematoma expansion and worse outcomes.

BACKGROUND AND PURPOSE: Ventriculostomy-associated infection (VAI) is a serious complication of external ventricular drainage (EVD). Infection rates and risk factors are variable in the literature due to heterogeneity of EVD procedures and management. This study aimed to investigate the incidence of VAI and its associated factors in two institutions with identical EVD procedural and management protocols. METHODS: The authors reviewed the medical records of patients older than 18 years who received EVD placements between January 2015 and December 2020 in two institutions under a single healthcare system. RESULTS: A total of 216 patients with 328 catheters was included for analysis. Twenty-three VAIs were identified, a 10.6% VAI rate. VAI was associated with a shorter duration of first EVD (9.7 days vs. 11.8 days, P = 0.018), a longer total EVD duration (28.0 days vs. 16.1 days, P < 0.001), a longer procedural time (72 minutes vs. 40 minutes, P < 0.001), catheterization at non-Kocher’s points (34.7% vs. 12.5%, P = 0.010), cerebrospinal fluid (CSF) leak (8.7% vs. 1.6%, P = 0.030), craniotomy (87.0% vs. 61.7%, P = 0.020), and other systemic infections (30.4% vs. 9.3%, P = 0.012). On multivariate analysis, the first EVD duration (OR = 0.095, P < 0.001), total EVD duration (OR 1.128, P < 0.001), EVD placement at non-Kocher’s point (OR 4.545, P = 0.012), and other systemic infections (OR = 5.117, P = 0.024) were associated independently with VAI. There was no statistical difference in VAI rate between patients with or without prophylactic EVD exchange at 14 days (6.8% vs. 12.6%, P = 0.247). CONCLUSIONS: Concomitant systemic infection and placement of an EVD catheter at a non-Kocher’s point were independently associated with VAI. Prophylactic EVD exchange at 14 days did not lower VAI rate.

Objective An infundibulum of the posterior communicating artery (PcomA) or infundibular dilatation (ID) is considered to be a benign anatomical variant. However, some evidence suggests that ID is a pre-aneurysmal state. This case series presents cases of ruptured IDs and aneurysms originating from the IDs.Methods Between April 2002 and June 2020, 1337 patients were treated for aneurysmal subarachnoid hemorrhage (SAH). Among them, 7 patients with ruptured PcomA IDs were identified. Rupture IDs of the PcomA were categorized into 1) direct rupture of IDs, and 2) rupture of aneurysms originating from IDs. The clinical and radiographic factors were retrospectively reviewed.ResultsTwo patients experienced direct rupture of IDs, while the other 5 patients presented with ruptured aneurysms originating from IDs. The 2 patients with direct rupture of IDs at presentation were relatively younger (< 50 years), while the other 5 patients with ruptured aneurysms originating from IDs were over 70 and had a history of aneurysmal SAH due to other intracranial aneurysms. Ruptured IDs were treated with microsurgery or endovascular treatment. There were no complications related to the procedure for securing ruptured IDs. Five (71.4%) patients showed favorable outcomes. One patient with initial Hunt and Hess grade 4 died due to initial brain damage with cerebral vasospasm and medical complications.ConclusionsID of the PcomA rarely causes SAH with or without aneurysm formation. Thus, patients with IDs of the PcomA should be carefully followed up for a long period, especially those with a history of aneurysmal SAH.

Objective The purpose of this study was to report the authors' preliminary experience using the Amplatzer Vascular Plug (AVP) (St. Jude Medical, Plymouth, MN, USA) for parent artery occlusion of the internal carotid artery (ICA) or vertebral artery (VA). Materials and Methods Between September 2008 and December 2015, we performed 52 therapeutic parent artery occlusions (PAOs) by an endovascular technique. Among them, 10 patients underwent PAO of the carotid or vertebral arteries using AVPs. Clinical and radiographic data of these patients were retrospectively reviewed. Results The devices were used for VA dissection that presented with subarachnoid hemorrhage (SAH) in five patients, traumatic arteriovenous fistula (AVF) in two patients, spontaneous AVF in one patient, recurrence of carotid-cavernous fistula (CCF) in one patient, and symptomatic unruptured giant ICA aneurysm in one patient. The devices were used in conjunction with detachable and/or pushable coils and in the extracranial segments of the ICA or VA. Complete occlusion of the parent artery was achieved in all patients. There was one intra-procedural rupture of the VA dissection during coiling prior to using the device. Conclusion Results from the current series suggest that the AVP might be used for therapeutic PAO in the extracranial segments of the ICA or VA.