Suction thrombectomy of distal medium vessel occlusion using microcatheter during mechanical thrombectomy for acute ischemic stroke: A case series.

While mechanical thrombectomy is known to be effective for distal medium vessel occlusion (DMVO) as well as large vessel occlusion, tortuous DMVO are predisposed to vessel injury during stent retriever thrombectomy. Furthermore, getting access to the thrombus may be difficult during suction thrombectomy using a dedicated suction catheter. Most studies describe DMVO treatment using stent retrievers and dedicated suction catheters, but there are limited studies reporting DMVO treated with suction thrombectomy using a microcatheter. Herein, we describe three cases of DMVO treated with suction thrombectomy that was performed using a microcatheter and subsequently showed good results. Therefore, suction thrombectomy using a microcatheter is a viable alternative treatment for tortuous DMVO.

Risk factor analyses of contrast leakage and contrast-induced encephalopathy following coil embolization for unruptured intracranial aneurysm.

BACKGROUND: Contrast-induced encephalopathy (CIE) following endovascular interventions is a rare but serious complication. This study aimed to investigate the risk factors of contrast leakage (CL) and CIE in patients who underwent coil embolization of unruptured intracranial aneurysms (UIAs). METHODS: Patients with UIAs who underwent coil embolization at a single tertiary institute between January 2019 and January 2022 were enrolled retrospectively. CL was defined as cortical or subcortical contrast enhancement with effacement of the cortical sulci. CIE was defined as the new onset of neurological deficits associated with CL. Following the procedure, all patients underwent CT scans, and MRI scans were performed on those with symptoms. Patient and procedural risk factors were investigated. RESULTS: In total, 459 patients were analyzed. The median procedure time and contrast dose were 69 min and 96 mL, respectively. CL was evident in 35 patients. In the multivariate analysis, hypertension, large aneurysm, longer procedure time, and greater contrast dose were associated with CL. CIE was diagnosed in 19 patients, and the risk factors included large aneurysm, longer procedure time, and greater contrast dose. The procedure time was predictive of both CL (P<0.001) and CIE (P=0.01). The optimal cut-off value for procedure time was 81.5 min. All CIE patients recovered completely within 8-96 hours. CONCLUSIONS: A large aneurysm and prolonged procedure time may increase the patient's risk of CL and CIE due to increased contrast exposure. Patients who underwent a procedure that exceeded 1.5 hours necessitate post-procedure evaluation and monitoring.

Distal stenting technique for coil embolization of early branch aneurysms of middle cerebral artery.

BACKGROUND AND PURPOSE: Stent-assisted coil embolization of early branch aneurysms of the middle cerebral artery (MCA) can sometimes be challenging due to the small diameter and acute angle of the branches. This study aimed to analyze the treatment results and report the feasibility and outcomes of the distal stenting technique for these aneurysms. MATERIALS AND METHODS: The distal stenting technique was used for 15 wide-neck MCA aneurysms (females, 10; males, 5; mean age, 65.1 years) originating from the early branch between December 2018 and October 2021. The average sizes of the dome, depth, and neck of the aneurysms were 4.17 mm (range: 2.99-6.21 mm), 2.86 mm (range: 1.82-3.72 mm), and 3.42 mm (range: 2.44-4.32 mm), respectively. RESULTS: The average diameter of the stents was 4.0 mm (3.0 mm, 3; 4.0 mm, 6; 4.5 mm, 6). Stents were successfully deployed in all 15 aneurysms (100%). The average length of the procedure was 69 min (range: 45-117 min). On postoperative angiography, nine (60.0%) aneurysms were completely occluded, four (26.7%) had neck remnants, and two (13.3%) had contrast flow in the sac. During the procedure, vasospasm and thrombus formation occurred in one case each, but no neurological sequelae were observed. On follow-up digital subtraction angiography of the 10 aneurysms after an average of 13.7 months (range: 12-18 months), the branches were well preserved, and neck remnants were noted in four aneurysms (40.0%). No thromboembolic events occurred during the clinical follow-up. CONCLUSION: The distal stenting technique using an open-cell stent can be a good option for coil embolization of early branch MCA aneurysms.

Endovascular recanalization therapy for patients with acute ischemic stroke with hidden aortic dissection: A case series.

Aortic dissection is one of the causes of acute ischemic stroke. Endovascular recanalization therapy (EVT) has emerged as an essential treatment for acute ischemic stroke due to large artery occlusion. However, it is rarely performed in the situation of hidden aortic dissection (AD). Two patients presented to the emergency room with focal neurologic deficits. The first patient was diagnosed with right internal carotid artery (ICA) occlusion. Angiography revealed that the ICA was occluded by the dissection flap. After a stent deployment in the proximal ICA, the antegrade flow was restored. The patient was diagnosed with AD on chest computed tomography (CT) after EVT. For the second patient, intraarterial thrombectomy was performed to treat left middle cerebral artery occlusion. AD was first detected on echocardiography, which was performed after EVT. Herein, we report successful endovascular recanalization therapy performed in two patients with acute ischemic stroke in the situation of undiagnosed aortic dissection. We also reviewed previous case reports and relevant literature.

Rotational Vertebral Artery Syndrome (Bow Hunter's Syndrome): A Rare Differential Diagnosis in Patients With Syncope.

Syncope is a common symptom in clinical practice. Rotational vertebral artery occlusion syndrome, also referred to as Bow Hunter's syndrome (BHS), is a rare condition associated with syncope and is caused by mechanical occlusion or stenosis secondary to mechanical compression of the vertebral artery during head rotation. BHS is associated with a multifactorial etiology; however, in most cases, this condition is attributed to degenerative changes. A 53-year-old man visited our hospital for the evaluation of fainting and dizziness episodes that occurred when he turned his head. Evaluation as an outpatient in the Department of Neurology showed a positive result on the Frenzel goggle test. Transfemoral cerebral angiography performed at the Department of Neurosurgery revealed stenosis of the proximal right vertebral artery. Complete occlusion of the vertebral artery was observed, and the head was turned to the right. Decompression and fusion were performed, and the contributory lesion was completely removed. Postoperative imaging confirmed complete removal of the spur and sufficient vertebral artery decompression; the patient's symptoms resolved postoperatively.

Treatment results of anterior choroidal artery aneurysms treated mostly with coil embolization: A single-center experience.

BACKGROUND: Anterior choroidal artery (AchA) aneurysms are usually small in diameter because of the size of the involved artery and are often wide-necked. Coil embolization of AchA aneurysm is thus challenging because of serious risks, such as thromboembolic occlusion of artery and perforation of aneurysm dome. Therefore, aneurysmal neck clipping remains widely performed despite a recent increase in the use of coil embolization for aneurysm treatment. We report the treatment results of AchA aneurysms mostly (92.3%) treated with coil embolization at our institute. METHODS: The database and medical records of patients who underwent coil embolization for AchA aneurysms were retrospectively analyzed. The clinical and imaging results and procedure-related complications were investigated after coil embolization performed between January 2006 and March 2022 at our institute. RESULTS: In total, 96 AchA aneurysms comprising 65 unruptured and 31 ruptured aneurysms, including only 1 ruptured aneurysm (1.0%) re-embolized at postoperative day 192 because of coil compaction, were evaluated. After the initial coil embolization, complete occlusion was attained in 41, residual neck in 45, and residual aneurysm in 10 patients. Follow-up radiological studies after 6-174 months were performed for 80 aneurysms. Complete occlusion was noted in 57 patients, residual neck in 22, and residual aneurysm in 1. The dysarthria experienced by one (1.0%) patient was the only symptomatic procedure-related complication. After coil embolization, neither delayed new rupture nor re-rupture was observed. CONCLUSIONS: The results of this study demonstrate that coil embolization is a safe and effective treatment option for patients with AchA aneurysms.

A Huge Radiation-Induced Cavernous Hemangioma Following Stereotactic Radiosurgery for Meningioma: A Case Report.

Radiation-induced cavernous hemangiomas (RICHs) have been increasingly reported as a late complication after conventional radiotherapy. RICH after stereotactic radiosurgery (SRS) is extremely rare and the few cases have been reported to demonstrate their properties. A 72-year-old female patient presented with progressive neurologic deficits. She underwent tumor surgery for meningioma 13 years ago and two times of SRS for treating a residual tumor. Newly-developed mass was 4.3 cm-sized heterogeneously enhancing mass with severe cerebral edema. She underwent surgical resection and the histologic examinations revealed organized hematoma. Finally, it was diagnosed as a RICH following SRS based on radiological and histological findings and a history of multiple radiosurgeries. Clinical, radiological, and histological features of a RICH following SRS were discussed in this report.

A Deep Neural Network-Based Model Predicting Peritumoral Edema After Radiosurgery for Meningioma.

BACKGROUND: Gamma Knife radiosurgery (GKS) is a promising treatment option for meningioma. However, the incidence of peritumoral edema (PTE) following GKS has been reported to be 7%-38%. This study aimed to develop a predictive model for post-GKS PTE using a deep neural network (DNN) algorithm. METHODS: Patients treated with GKS for meningioma between November 2012 and February 2020 at a single tertiary center were reviewed. The primary outcome was newly developed or aggravated PTE after GKS. Clinical data, including radiosurgical parameters, were collected, and imaging data obtained at the time of GKS were incorporated into the model using a 50-layered residual neural network, ResNet50. Consequently, the model efficiency was evaluated considering the accuracy and area under the receiver operating curve (AUC) values. RESULTS: A total of 202 patients were included in this study. The median tumor volume was 2.3 mL, and the median prescription dose was 13 Gy. PTE was observed before GKS in 22 patients. Post-GKS PTE was evident in 28 patients (13.9%), which further evolved to radiation necrosis in 5 patients. The accuracy and AUC values of the hybrid data model based on both clinical and imaging data were 0.725 and 0.701, respectively. The performance of the hybrid data model was superior to that of the other models based on clinical or image data only. CONCLUSIONS: The DNN-based model using both clinical and imaging data exhibited fair results in predicting post-GKS PTE in meningioma treatment. Predictive models using imaging data may be helpful in prognostic research.

Reverse Trans-Sellar Neuroendoscopic Management of a Large Rathke's Cleft Cyst Causing Obstructive Hydrocephalus: A Case Report.

Symptomatic Rathke's cleft cysts (RCCs) can be treated by surgical procedures, usually through an endonasal transsphenoidal corridor using either a microscope or an endoscope. We report a large suprasellar extended RCC causing obstructive hydrocephalus, which was efficiently managed by a novel surgical route named "reverse" trans-sellar approach using transventricular neuroendoscopy. A 48-year-old woman complained of persistent headache and a tendency to fall that had begun 6 months previously. The images obtained from MRI scan showed intra- and supra-sellar cystic masses occupying the third ventricle with obstruction of the foramina of Monro and the aqueduct of Sylvius. The cystic wall showed a slight enhancement, and the cystic contents showed iso-signal intensity on T1-and T2-weighted images. Instead of trans-nasal trans-sellar surgery, we decided to operate using a conventional transventricular endoscope. A thin cystic capsule, which blocked the foramina of Monro and the aqueduct of Sylvius, was fenestrated and removed and a third ventriculostomy was performed. The defect in the infundibulum between sellar and suprasellar cysts was widened and used as a corridor to drain cystic contents (reverse trans-sellar route). The final pathological finding revealed an RCC with focal metaplasia. We efficiently managed a large RCC by transventricular neuroendoscopic surgery with cyst fenestration and third ventriculostomy and simultaneously drained the sellar contents using a novel surgical route. Reverse trans-sellar neuroendoscopic surgery is a relevant treatment option for selective patients with large suprasellar extensions of RCCs.

Usefulness of combination usage of balloon guide catheter with contact aspiration thrombectomy.

BACKGROUND: Angiographic outcomes of contact aspiration thrombectomy (CAT), a frontline thrombectomy strategy, can vary depending on balloon guide catheter (BGC) usage, stroke etiology, and occlusion location. The purpose of this study was to analyze conditional outcomes of CAT to determine which result in maximum angiographic benefits. METHODS: Patients who received CAT for anterior circulation occlusive stroke between January 2017 and December 2018 were included. Angiographic and clinical outcomes were compared relative to BGC use, stroke etiology, and occlusion location. Multivariable analyses for first-pass reperfusion (FPR) and favorable clinical outcome were performed. RESULTS: Of 160 included patients, the rates of FPR, successful reperfusion after CAT, final successful reperfusion, and favorable clinical outcome were 43.1%, 58.1%, 81.9%, and 60.6%, respectively. BGC use was associated with a higher rate of FPR, successful reperfusion after CAT, a lower rate of distal embolization, and faster reperfusion. Based on subgroup analysis, BGC usage in ICA, MCA M1 occlusion, and cardioembolism were associated with higher FPR, successful reperfusion after CAT, and lower distal embolization. Faster reperfusion was achieved in ICA occlusions and cardioembolisms. BGC usage was an independent predictor of FPR. Favorable clinical outcome was associated with male gender, low initial NIHSS score, fast onset to reperfusion, and FPR. CONCLUSIONS: In CAT, BGC usage was associated with better angiographic outcomes, including higher FPR, successful reperfusion after CAT, prevention of distal embolization, and faster reperfusion, especially in proximal occlusions and cardioembolisms. These conditions may play a role in maximizing the benefits of CAT.

Retrograde stenting through anterior communicating artery in coil embolization of the posterior communicating artery aneurysm: contralateral approach.

During coil embolization of wide-necked posterior communicating artery (PcomA) aneurysms, stent assistance is sometimes limited if PcomA is acutely angled at its origins from saccular neck. Herein, we present two instances where retrograde stenting was used for coil embolization of PcomA aneurysms. Both procedures involved a contralateral approach via anterior communicating artery (AcomA). To achieve this, the stent-delivery microcatheter was inserted retrograde from contralateral to ipsilateral internal carotid artery (ICA) across AcomA, arriving at ipsilateral PcomA. A separate microcatheter, passed through ipsilateral ICA, was then used to select the aneurysm sac for coil delivery. Coil embolization ultimately took place under protection of a horizontally placed stent extending from PcomA to terminal ICA. Each aneurysm was properly coiled and occluded, without procedural complications. This stenting technique is a reasonable option, offering a means of strategic coil embolization in wide-necked PcomA aneurysms and providing complete neck coverage through contralateral access.

Duration of Vasodilatory Action After Intra-arterial Infusions of Calcium Channel Blockers in Animal Model of Cerebral Vasospasm.

BACKGROUND: In medically refractory vasospasm, invasive intervention may be required. A commonly used approach is intra-arterial (IA) drug infusion. Although calcium channel blockers (CCBs) have been widely applied in this setting, studies comparing their efficacies and durations of action have been few. This study was performed to compare attributes of three CCBs (nicardipine, nimodipine, and verapamil), focusing on duration of the vasodilatory action based on angiography. METHODS: Vasospasm was produced in New Zealand white rabbits (N = 22) through experimentally induced subarachnoid hemorrhage and confirmed in each via conventional angiography, grouping them by IA-infused drug. After chemoangioplasty, angiography was performed hourly for 5 h to compare dilated and vasospastic arterial diameters. Drug efficacy, duration of action, and changes in mean arterial pressure (relative to baseline) were analyzed by group. RESULTS: Effective vasodilation was evident in all three groups immediately after IA drug infusion. The vasodilative effects of nimodipine and nicardipine peaked at 1 h and were sustained at 2 h, returning to initial vasospastic states at 3 h. In verapamil recipients, effects were more transient by comparison, entirely dissipating at 1 h. Only the nicardipine group showed a significant 3-h period of lowered blood pressure. CONCLUSIONS: Although nimodipine and nicardipine proved longer acting than verapamil in terms of vasodilation, their effects were not sustained beyond 2 h after IA infusion. Further study is required to confirm the vasodilatory duration of IA CCB based on perfusion status, and an effort should be made to find new alternative to extend the duration.

Novel Noncrossing Y-Stent Technique Using Tapered Proximal End of a Solitaire AB Stent for Coil Embolization of Wide-Neck Bifurcation Aneurysms.

The crossing Y-stent method is one of the indispensable techniques to achieve sufficient neck coverage during coil embolization of bifurcation aneurysms with a wide neck and/or branch incorporation. However, the inevitable hourglass-like expansion of the second stent at the crossing point can result in insufficient vessel wall apposition, reduced aneurysm neck coverage, delayed endothelialization, and subsequent higher risks of acute or delayed thrombosis. It also interferes with engagement of the microcatheter into the aneurysm after stent installation. We expected to be able to reduce these disadvantages by installing a noncrossing type Y-stent using the Solitaire AB stent, which is fully retrievable with a tapered proximal end. Here we report the techniques and two successful cases.

How to Find Dural Defect of Spinal Extradural Arachnoid Cyst.

Spinal extradural arachnoid cysts (SEACs) are rare and usually asymptomatic, and they usually do not require surgical treatment. If symptoms manifest, however, surgical treatment is required. A 25-year-old male patient complained of impotence upon admission. Magnetic resonance images (MRIs) of his lumbar spine showed a SEAC located longitudinally from the T11 to L3, which was accompanied by thecal sac compression. Verifying the location of the dural defect is crucial for minimizing surgical treatments. Cystography, myelography, and lumbar spine MRI were conducted to locate the leak in real-time; however, it was not found. Hence, the location of the cerebrospinal fluid leak was estimated based on cystography, computed tomography, myelography, and MRI findings. We suggest that the region with the earliest contrast-filling, as well as the middle and widest area of the cyst, may correspond to the location of the dural defect.

Endovascular coil embolization for unruptured intracranial aneurysms in patients over 80 years of age.

OBJECTIVE: As the average life span in modern society continues to increase, much interest is focused on high-risk procedures in elderly patients, including major surgical operations. We investigated the results of endovascular coiling of unruptured intracranial aneurysms (UIA) in patients over 80 years of age. METHODS: We retrospectively analyzed 39 patients aged over 80 years who underwent coil embolization for UIA between April 2007 and April 2019 at our hospital. RESULTS: Complete occlusion on digital subtraction angiography (DSA) immediately after surgery was performed in 44 (84.6%) of 52 cases of cerebral aneurysms. Four patients (7.7%) had residual aneurysmal necks, and four (7.7%) had contrast flow in the aneurysmal sac. Follow-up magnetic resonance angiography (mean: 8.2 months) was performed in 37 aneurysms in 24 patients. There was evidence of blood flow in the neck in seven cases (18.9%) and aneurysm in two cases (5.4%). Follow-up DSA (mean: 20.5 months) was performed in 14 aneurysms in 11 patients, and 11 aneurysms (78.6%) had complete occlusion, 1 aneurysm (7.1%) had an aneurysmal neck, and 2 aneurysms (14.3%) had contrast filling into the aneurysmal sac. Coil embolization procedure-related complications occurred in 3 patients (7.7%). Cerebral infarction occurred in 1 (2.6%), arterial dissection in 1 (2.6%), and hypoesthesia in 1 (2.6%). CONCLUSIONS: Active treatment of UIA in elderly patients over 80 years of age through endovascular coil embolization can be considered.

Association of plasma level of growth differentiation factor-15 and clinical outcome after intraarterial thrombectomy.

BACKGROUND AND PURPOSE: As intraarterial thrombectomy (IAT) has been actively practiced, blood biomarkers that can predict outcomes after IAT have drawn attention. Growth differentiation factor-15 (GDF-15) is a stress-responsive cytokine and the levels are increased during inflammation or other pathological conditions of various tissues, including the brain. However, GDF-15 levels have not been reported as a biomarker for IAT outcomes. This study was performed to evaluate whether GDF-15 was related to the extent of brain damage and whether it could predict patient prognosis after IAT. METHODS: Patients who showed large arterial occlusion and significant diffusion-perfusion mismatch on imaging underwent IAT. A total of 62 patients who underwent IAT and had blood samples for GDF-15 measurements were enrolled from July 2013 to May 2015. We assessed the infarct severity by consecutive changes on the National Institutes of Health Stroke Scale (NIHSS) during admission and the size of the infarction on brain imaging. Modified Rankin Scale scores (mRS) from 0 to 2 were considered good outcomes, representing functional independence at discharge and three months later. RESULTS: The levels of GDF-15 at the time of admission were significantly correlated with the NIHSS scored at 24 hours (r = 0.306, p = 0.016), three days after IAT (r = 0.261, p = 0.041), and at discharge (r = 0.266, p = 0.037), as well as the infarct size on diffusion-weighted image taken 24 h after IAT (r = 0.452, p = 0.001), but the levels were not correlated with the initial NIHSS or the infarct size before IAT. Multiple logistic regression showed that GDF-15 levels were an independent predictor of functional independence (mRS 0 - 2) at discharge (p = 0.028) and three months after IAT (p = 0.019). Other factors that could predict prognosis were good collateral status on the initial brain angiography and rapid recanalization within six hours from symptom onset. CONCLUSION: The GDF-15 level at the time of admission showed a significant positive correlation with the severity of cerebral damage and clinical outcome after IAT. This suggests that GDF-15 can provide useful prognostic information for patients who successfully underwent IAT in an emergency setting.

Ten-Year Experience of Dural Reconstruction Using a Collagen Matrix Inlay Graft in Posterior Fossa Surgery: A Propensity Score-Matched Study.

BACKGROUND: Considering that primary watertight dural closure is not always possible following posterior fossa surgery, several methods of dural reconstruction were proposed to reduce the risk of cerebrospinal fluid (CSF) leakage. This study aimed to evaluate the efficacy of collagen matrix inlay graft compared with other techniques in a propensity score-matched cohort. METHODS: Between 2000 and 2019, 176 consecutive patients who underwent posterior fossa surgery were enrolled. Of these, 103 patients underwent dural reconstruction with collagen matrix inlay graft (inlay group). After propensity score matching, 67 pairs were derived. The primary outcome was the development of CSF leakage. Pseudomeningocele and surgical site infection were also investigated. RESULTS: Median follow-up period was 53.9 months. None of the patients in the inlay group had CSF leakage; however, leakage was evident in 5 patients (6.8%) who underwent dural reconstruction without a collagen matrix inlay graft (no-inlay group; P = 0.011). Pseudomeningocele was noted in 1 (1.4%) patient in the no-inlay group, while surgical site infection was noted in 3 (3.0%) patients in the inlay group and 4 (5.5%) patients in the no-inlay group. None of the surgical site infections were related to the use of the inlay graft. After propensity score matching, CSF leakage was still prevalent in the no-inlay group (P = 0.042). CONCLUSIONS: Dural reconstruction using a collagen matrix inlay graft efficiently reduces CSF leakage after posterior fossa surgery and does not increase the risk of postoperative infection and inflammation. It seems to be a feasible option for dural reconstruction.

Simultaneous neck coverage and branch preservation using the proximal portion of a self-expandable open-cell stent for embolization of distal internal carotid artery aneurysms: multi-center, long-term results.

PURPOSE: We report the long-term results of a modified stent-assisted coil embolization technique using the far proximal part of a self-expanding open-cell stent. The technique was used to cover the neck of the aneurysm while simultaneously preserving the branches of the distal internal carotid artery in patients with aneurysms of the posterior communicating (Pcom) and anterior choroidal arteries (AchA). METHODS: We performed a retrospective review of the prospectively maintained databases at two tertiary neurosurgical centers to identify all patients who underwent embolization of Pcom or AchA aneurysms using this technique between January 2014 and July 2019. Postoperative and follow-up clinical and radiological results for initial (n = 16) or re-do (n = 4) embolizations were analyzed. RESULTS: We identified 19 patients with 20 (16 Pcom and 4 AchA) unruptured (n = 19) or ruptured (n = 1) aneurysms. Eighteen among 20 stents (90.0%) were deployed successfully, and complete occlusions were initially attained in 18 aneurysms (90.0%). At follow-up examinations 8 to 56 months later, 6 of 14 aneurysms (42.8%) showed neck remnants. All of the branches were saved and no thromboembolic event, rupture, or sequelae were noted during or after the procedures. CONCLUSION: These results suggest that this modified stent-assisted technique is a feasible and reasonable alternative to conventional stent deployment for coil embolization of wide-necked sidewall aneurysms in the distal ICA.

Spontaneous Spinal Subdural and Subarachnoid Hemorrhage with Concomitant Intracerebral Hemorrhage: A Case Report.

Most cases of spinal subdural hematoma are very rare and result from iatrogenic causes, such as coagulopathy or a spinal puncture. Cases of non-traumatic spinal subdural hematoma accompanied by intracranial hemorrhage are even more rare. There are a few reports of spontaneous spinal subdural hematoma with concomitant intracranial subdural or subarachnoid hemorrhage, but not with intracerebral hemorrhage. Especially in our case, the evaluation and diagnosis were delayed because the spontaneous intracerebral hemorrhage accompanying the unilateral spinal subdural and subarachnoid hemorrhages caused hemiplegia. We report a case of spinal subdural and subarachnoid hemorrhage with concomitant intracerebral hemorrhage, for the first time, with a relevant literature review.

Is arachnoid cyst a static disease? A case report and literature review.

INTRODUCTION: The increasing use of intracranial imaging has led to more frequent diagnoses of arachnoid cysts (ACs). Although ACs are a frequent finding on neuroimaging in children, the prevalence and natural history of these cysts are not well defined. Most ACs may persist and remain asymptomatic throughout life and not require treatment. However, there have been some case reports of ACs that have become larger or smaller over time and, in rare cases, have even spontaneously resolved. It is the authors' practice to recommend serial neuroimaging in patients with asymptomatic sylvian ACs and not offer surgery to patients without symptoms, even in those with a relatively large cyst. CASE REPORT: The present article describes a case involving a 6-year-old boy with a large, asymptomatic AC in the left Sylvian fissure involving the temporo-frontal region, which resolved spontaneously during the 2-year follow-up period after initial diagnosis without any surgical intervention. Currently, at the 7-year follow-up, the patient has remained neurologically intact, attends school, and is symptom-free. CONCLUSION: Clinicians should be mindful of the possibility of spontaneous regression when encountering patients with asymptomatic and/or incidentally diagnosed sylvian ACs.