Pancytopenia represents a unique challenge for primary care doctors and its etiological causes encompass various specialties, including hematology and rheumatology. Despite the existence of effective tests such as bone marrow biopsy and immunoassays to rule out the potential causes of pancytopenia, it is often difficult to pinpoint the exact diagnosis. In this case report, we have described such a ‘gray zone’ patient, who presented with pancytopenia, neutropenia, and splenomegaly, and was being treated for fungal pneumonia before being transferred to Severance Hospital (department of family medicine). As the patient had a 10-year history of multiple, long-term hospital admissions that were having a severely debilitating impact on the quality of life, we performed a partial splenic embolization as a potential cure for the symptoms. Although this induced acute blood count recovery, it failed to prevent eventual mortality from septic shock.

Pancytopenia represents a unique challenge for primary care doctors and its etiological causes encompass various specialties, including hematology and rheumatology. Despite the existence of effective tests such as bone marrow biopsy and immunoassays to rule out the potential causes of pancytopenia, it is often difficult to pinpoint the exact diagnosis. In this case report, we have described such a ‘gray zone’ patient, who presented with pancytopenia, neutropenia, and splenomegaly, and was being treated for fungal pneumonia before being transferred to Severance Hospital (department of family medicine). As the patient had a 10-year history of multiple, long-term hospital admissions that were having a severely debilitating impact on the quality of life, we performed a partial splenic embolization as a potential cure for the symptoms. Although this induced acute blood count recovery, it failed to prevent eventual mortality from septic shock.

Management of cavernous sinus dural arteriovenous fistula (CSDAVF) continues to present significant challenges, particularly when the inferior petrosal sinus is thrombosed, collapsed, or angiographically invisible. In this study, we introduce facilitated retrograde access via the facial vein, which is employed in the transvenous embolization of CSDAVF with isolated superior ophthalmic venous drainage. We also present illustrative cases and technical points.

Objective: : Transvenous embolization (TVE) via an occluded inferior petrosal sinus (IPS) in a cavernous sinus dural arteriovenous fistula (CSDAVF) is challenging, often requiring navigation of a microcatheter through resistive obstacles between the occluded IPS and shunted pouch (SP), although the reopening technique was successfully performed. We report five cases of successful access to the cavernous sinus (CS) or SP using the rigid-tipped microguidewire such as chronic total occlusion (CTO) wire aiming to share our initial experience with this wire. Methods: : In this retrospective study, four patients with CSDAVF underwent five procedures using the CTO wire puncture during transfemoral transvenous coil embolization. Puncture success, shunt occlusion, and complications including any hemorrhage and cranial nerve palsy were evaluated. Results: : Despite successful access through the occluded IPS, further entry into the target area using neurointerventional devices was impossible due to a short-segment stricture before the CS (three cases) and a membranous barrier within the CS (two cases). However, puncturing these structures using the rigid-tipped microguidewire was successful in all cases. We could advance the microcatheter over the rigid-tipped microguidewire for the navigation to the SP and achieved complete occlusion of the SP without complications. Conclusion : The use of the rigid-tipped microguidewire in the TVE via the occluded IPS of the CSDAVF would be feasible and safe.

Purpose: Wide-necked aneurysms in the circle of Willis (CoW) are prone to recur due to reciprocal bidirectional flow. We present a novel concept of coil embolization to prevent recurrence that uses physiologic flow diversion at the CoW. Materials and Methods: We enrolled 14 patients (15 aneurysms) who underwent aneurysm coiling for wide-necked aneurysms with asymmetric bidirectional inflow into the aneurysm. Four patients had recurrent aneurysms after coiling. The concept of physiologic flow diversion included obliterating antegrade flow into the aneurysm sac as well as opposite CoW flow by performing compact coil packing with intentional protrusion out of the aneurysm neck to the communicating part. Results: Fifteen aneurysms, including 4 recurrent aneurysms, in an anterior communicating artery (n=7), posterior communicating artery (n=5), and tip of the basilar artery (n=3) were treated with coil embolization (n=10) and stent-assisted coiling (n=5). All aneurysms had a wide neck, and the mean largest diameter was 9.0 mm. The mean packing density was 45.1%. Twelve aneurysms were completely occluded, and 3 aneurysms had tiny residual neck remnants. There was neither a neurological event nor recurrence during the mean 12.5 months of follow-up. Conclusion Wide-necked aneurysms at the CoW tend to recur. As a strategy to prevent a recurrence, physiologic flow diversion can be an option in treating wide-necked aneurysms in the CoW.

Purpose: This study aimed to evaluate the effectiveness, safety, and technical considerations of flow diverter (FD) treatment using a Flow Re-direction Endoluminal Device (FRED) for unruptured intracranial vertebral artery dissecting aneurysms (VADAs). Materials and Methods: We conducted a retrospective study of 23 patients with unruptured intracranial VADAs who underwent FD treatment using a FRED between June 2017 and August 2021. Symptoms, imaging findings, treatment strategies, and angiographic and clinical outcomes were evaluated. Dissections were categorized according to the dominance of the VA in which they occurred: dominant VA, co-dominant VA, and non-dominant VA. Results: All patients successfully underwent FD treatment with either a FRED (n=11) or FRED Jr. (n=12). Complete occlusion rates were 78.3% at 6-month follow-up magnetic resonance angiography and 91.3% at 12-month. There were no instances of complications, recurrence, or retreatment during a median follow-up of 20 months. Dissections occurred in the dominant VA in 3 cases (13.0%), the co-dominant VA in 13 cases (56.5%), and the non-dominant VA in 7 cases (30.4%). Intimal flap and true lumen stenosis were observed in 39.1% and 30.4% of cases, respectively. Four cases required a bilateral VA approach due to technical difficulties, all in the non-dominant VA. Conclusion Flow diversion treatment using a FRED for unruptured intracranial VADAs proved feasible and safe, yielding satisfactory occlusion rates. Technical challenges were more likely in lesions involving non-dominant VAs in the acute or subacute stage, mainly due to associated intraluminal lesions compromising the arterial lumen.

Hemangioblastomas (HBMs) are rare vascular tumors commonly located in the posterior fossa of adults. A mid-50s patient presented with sudden unconsciousness. Computed tomography scans revealed acute hemorrhages around the posterior fossa, predominantly in the subarachnoid space. Digital subtraction angiography (DSA) revealed an 8-mm round lesion filled with contrast agent, fed by the C1 segmental artery of the left vertebral artery (VA), showing early venous drainage to the spinal cord and brainstem. Emergent embolization was attempted under suspicion of a ruptured dural arteriovenous fistula, resulting in parent artery occlusion due to feeder selection failure. Follow-up DSA after a month depicted a persistent aneurysm via collaterals from both VAs. Consequently, the decision was made to proceed with surgical intervention, leading to the resection of the lesion, confirming its diagnosis as a HBM through histological examination. This case underscores the potential for misdiagnosis when HBMs with an intratumoral shunt mimic vascular shunt lesions.

Purpose: Coil embolization of paraclinoid aneurysms should be simple, safe, and effective considering the benign nature of the aneurysm. Here, we present a microcatheter stabilization technique using a partially inflated balloon for the treatment of paraclinoid aneurysms. Materials and Methods: This retrospective study included 58 patients who underwent balloon-assisted coiling (BAC) for unruptured paraclinoid aneurysms at a tertiary neuro-intervention center between January 2019 and March 2020. We applied a technique to stabilize the microcatheter’s position using the modified BAC technique in paraclinoid aneurysms showing various projections around the ophthalmic curve of the internal carotid artery. The basic concept of the technique is to place a partially inflated balloon just distal to the aneurysm neck and support the distal curve of the microcatheter using the proximal bottom of the balloon. Immediate radiological outcomes were analyzed, and clinical outcomes were evaluated with modified Rankin Scale (mRS) scores. Results: The BAC was successfully performed in 51 of 58 patients (88%). We treated the remaining seven patients by switching to stent-assisted coiling. We obtained a 37% mean packing density resulting in favorable occlusion in all 58 aneurysms (complete occlusion in 35 and residual neck in 23). There were no intraprocedural thromboembolic or hemorrhagic events except one that revealed an asymptomatic infarction after the procedure (1.7%). Magnetic resonance angiography follow-up was performed in 37 patients at an average of 11.8 months, in which 11 minor recurrences (29.7%) were found. There was no major recurrence nor retreatment. The mRS score was 0 in all patients during a mean follow-up of 17.7 months (range, 12–25 months). Conclusion The modified balloon-assisted coiling technique using a partially inflated balloon was safe and effective and could serve as an option for treating paraclinoid aneurysms.

Purpose: Coil embolization of paraclinoid aneurysms should be simple, safe, and effective considering the benign nature of the aneurysm. Here, we present a microcatheter stabilization technique using a partially inflated balloon for the treatment of paraclinoid aneurysms. Materials and Methods: This retrospective study included 58 patients who underwent balloon-assisted coiling (BAC) for unruptured paraclinoid aneurysms at a tertiary neuro-intervention center between January 2019 and March 2020. We applied a technique to stabilize the microcatheter’s position using the modified BAC technique in paraclinoid aneurysms showing various projections around the ophthalmic curve of the internal carotid artery. The basic concept of the technique is to place a partially inflated balloon just distal to the aneurysm neck and support the distal curve of the microcatheter using the proximal bottom of the balloon. Immediate radiological outcomes were analyzed, and clinical outcomes were evaluated with modified Rankin Scale (mRS) scores. Results: The BAC was successfully performed in 51 of 58 patients (88%). We treated the remaining seven patients by switching to stent-assisted coiling. We obtained a 37% mean packing density resulting in favorable occlusion in all 58 aneurysms (complete occlusion in 35 and residual neck in 23). There were no intraprocedural thromboembolic or hemorrhagic events except one that revealed an asymptomatic infarction after the procedure (1.7%). Magnetic resonance angiography follow-up was performed in 37 patients at an average of 11.8 months, in which 11 minor recurrences (29.7%) were found. There was no major recurrence nor retreatment. The mRS score was 0 in all patients during a mean follow-up of 17.7 months (range, 12–25 months). Conclusion The modified balloon-assisted coiling technique using a partially inflated balloon was safe and effective and could serve as an option for treating paraclinoid aneurysms.

Purpose: With the rapid expansion of the field of interventional neuroradiology (INR) and the diverse background of aspiring neuro-interventionists, there is an ever increasing need to establish consensus criteria for training and accreditation in INR. Materials and Methods: We performed a survey to explore the current state of criteria for training and accreditation in INR. The questionnaire consisting of 11 questions was emailed to the members of World Federation of Interventional and Therapeutic Neuroradiology (WFITN) worldwide. It was focused on the training charter, training program, qualifying examination, and education after training program as perceived by practitioners in each country. Results: A total of 52 WFITN members in 19 countries responded to the questionnaire. There was a huge variation internationally and nationally due to the unique situation and challenges in each country and institution. Criteria for training and accreditation in INR were well established in some countries of Europe, North America, and Asia but not specified in other countries. Conclusion It is critical to establish consensus criteria for training and accreditation in INR in order to ensure safe practice and continued expansion and development of INR as a specialty.