Surgical Results with Low-Grade Arteriovenous Malformations : A Single Center 14-Year Experience.

Objective: Advancements in surgical techniques for cerebral arteriovenous malformation (AVM) underscore its efficacy. Our research aims to showcase the positive outcomes of treating low-grade AVMs surgically, focusing on safety and effectiveness. Methods: We retrospectively reviewed 55 patients (36 males, 19 females, and average age 37.4 years) with Spetzler-Martin (S-M) grade 1 and 2 AVMs who underwent surgical resection between January 2009 and December 2022. Results: In our study, 55 patients with S-M grade 1 and 2 AVMs underwent surgical resection, evenly divided between grades 1 (50.9%) and 2 (49.1%). Intracranial hemorrhage was the primary symptom in 74.5% of cases. Pre-operative Glasgow Coma Scale (GCS) scores revealed 69.1% of patients scored above 13, with 18% below 8. Successful resection was achieved in 87.3%. Postoperatively, 95.5% of ruptured and 90.9% of unruptured AVM patients showed lower or same modified Rankin Scale scores. Poorer outcomes were significantly linked to lower GCS scores and intranidal/flow-related aneurysms through multivariate logistic regression. Postoperative seizures noted in 9 patients, were exclusive to the ruptured AVM group. Conclusion: Our findings indicate surgical resection as a beneficial treatment for low-grade AVMs, yielding high cure rates and positive functional outcomes in both ruptured and unruptured cases. Preoperative GCS scores and the presence of associated aneurysms are predictive of postoperative functional status. Additionally, managing postoperative seizures effectively is key to enhancing prognosis.

Spontaneous intracranial hypotension presenting with bilateral subdural hematoma: Decision-making and treatment strategies.

BACKGROUND: The timing and decision to drain subdural hematoma (SDH) in spontaneous intracranial hypotension (SIH) remains a dilemma. We reviewed our experience of bilateral SDH secondary to SIH, focusing on decision making and treatment strategies. METHODS: We retrospectively reviewed bilateral SDH secondary to SIH between March 2010 and September 2021. Baseline characteristics of patients, diagnosis, radiologic findings, treatments, and clinical outcome were investigated. RESULTS: Fifteen patients (7 men, 8 women) with bilateral SDH secondary to SIH were included in this study. Initially, patients were treated conservatively (4 patients, 26.7 %), with an epidural blood patch (EBP, 3 patients, 20.0 %), and SDH drainage followed by the Trendelenburg position (8 patients, 53.3 %). All 3 patients that were initially treated with EBP required SDH drainage. Of the 8 patients initially treated with SDH drainage via burr hole followed by Trendelenburg position, 7 patients showed sustained improvements without EBP; however, 1 patient needed EBP. Deterioration to coma occurred in 6 out of 15 patients (40.0 %). All 6 deteriorated patients immediately recovered after SDH drainage with Trendelenburg position; 5 achieved sustained improvement without EBP and 1 required EBP. During the follow-up period, 14 out of 15 patients (93.3 %) showed good recovery. CONCLUSIONS: Evacuation of SDH is not always necessary in SIH; however, we did not hesitate to perform hematoma drainage, in deteriorated patients or those with thick hematoma that is associated with significant sagging and cistern effacement. This can prevent irreversible neurologic complications. Moreover, the Trendelenburg position may help to achieve sustained improvement without additional treatment.

Intracranial-intracranial bypass strategies for the treatment of complex intracranial aneurysms: anatomical characteristics and surgical intervention.

OBJECTIVE: The effectiveness of revascularization for complex aneurysms is well-established. This study aimed to describe the technical characteristics and clinical efficacy of intracranial-to-intracranial (IC-IC) bypass for the treatment of complex intracranial aneurysms. METHODS: We retrospectively reviewed all patients with aneurysms who underwent a preplanned combination of surgical or endovascular treatment and IC-IC bypass at our institution between January 2006 and September 2023. IC-IC bypass techniques included four strategies: type A (end-to-end reanastomosis), type B (end-to-side reimplantation), type C (in situ side-to-side anastomosis), and type D (IC-IC bypass with a graft vessel). RESULTS: During the study period, ten patients with aneurysms each underwent IC-IC bypass surgery. Aneurysms were located in the middle cerebral artery (60.0%), anterior temporal artery (10.0%), anterior cerebral artery (20.0%), and vertebral artery (10.0%). There were three saccular aneurysms (30.0%), two fusiform aneurysms (20.0%), one dissecting aneurysm (10.0%), and four pseudoaneurysms (40.0%). We performed the type A strategy on five patients (50.0%), type B on one (10.0%), type C on one (10.0%), and type D on three (30.0%). During a mean period of 68.3 months, good clinical outcomes (modified Rankin Scale score, 0-2) were observed in all patients. Follow-up angiography demonstrated complete aneurysmal obliteration in all patients and good bypass patency in nine of ten patients (90.0%). CONCLUSION: The treatment of complex aneurysms remains a challenge with conventional surgical or endovascular treatments. IC-IC bypass surgery is a useful technique, associated with favorable clinical outcomes, for treating complex aneurysms.

Telemedicine Protocols for the Management of Patients with Acute Spontaneous Intracerebral Hemorrhage in Rural and Medically Underserved Areas in Gangwon State: Recommendations for Doctors with Less Expertise at Local Emergency Rooms.

Previously, we reported the concept of a cloud-based telemedicine platform for patients with intracerebral hemorrhage (ICH) at local emergency rooms in rural and medically underserved areas in Gangwon state by combining artificial intelligence and remote consultation with a neurosurgeon. Developing a telemedicine ICH treatment protocol exclusively for doctors with less ICH expertise working in emergency rooms should be part of establishing this system. Difficulties arise in providing appropriate early treatment for ICH in rural and underserved areas before the patient is transferred to a nearby hub hospital with stroke specialists. This has been an unmet medical need for decade. The available reporting ICH guidelines are realistically possible in university hospitals with a well-equipped infrastructure. However, it is very difficult for doctors inexperienced with ICH treatment to appropriately select and deliver ICH treatment based on the guidelines. To address these issues, we developed an ICH telemedicine protocol. Neurosurgeons from four university hospitals in Gangwon state first wrote the guidelines, and professors with extensive ICH expertise across the country revised them. Guidelines and recommendations for ICH management were described as simply as possible to allow more doctors to use them easily. We hope that our effort in developing the telemedicine protocols will ultimately improve the quality of ICH treatment in local emergency rooms in rural and underserved areas in Gangwon state.

Spontaneous Acute Epidural Hematoma Associated With Metastatic Hepatocellular Carcinoma: A Case Report.

Spontaneous acute epidural hematoma (AEDH) co-occurring with metastatic hepatocellular carcinoma (HCC) of the skull is rare, with only 7 documented cases in existing literature. This report describes the case of a 42-year-old man who presented with decreased consciousness following intermittent headaches following minor head trauma. Computed tomography imaging revealed an AEDH, prompting surgical intervention. Despite preliminary assumptions linking the causes of the trauma, surgical exploration revealed no evidence of traumatic injury. Instead, an infiltrative soft-tissue mass within the skull was identified. Histopathological examination confirmed that the mass was a metastatic HCC. Despite the successful hematoma evacuation, the patient's neurological status did not improve. This case underscores the importance of considering metastatic disease in the differential diagnosis of AEDH, particularly in patients with a history of malignant tumors, irrespective of prior indications of bone metastasis. Furthermore, it emphasizes the need to enhance diagnostic and therapeutic strategies for such complex cases.

Microsurgical strategies for small unruptured dorsal internal carotid artery aneurysms.

OBJECTIVE: This study aimed to develop microsurgical strategies based on the anatomical relationship between dorsal internal carotid artery (ICA) aneurysms, the falciform ligament (FL), and the anterior clinoid process (ACP). METHODS: Between 2017 and 2022, 25 patients with unruptured dorsal ICA aneurysms (less than 4 mm in diameter) underwent microsurgical direct clipping. These cases involved the left ICA (n=17) and the right ICA (n=8), with a mean aneurysm size of 3.3 mm (range, 2.5 to 4 mm). We used computed tomography angiography (CTA) and digital subtraction angiography to elucidate the anatomical relationship between dorsal ICA aneurysms and other structures. All procedures involved an ipsilateral pterional approach with securement of the ipsilateral cervical ICA for proximal control. RESULTS: Among the 25 dorsal ICA aneurysms, 8 (32%) were clipped without the FL being incised. Another 5 (20%) were clipped solely after the FL was cut. For the remaining 12 cases, the aneurysms were successfully clipped following FL incision and partial ACP removal. Patients exhibited favorable postoperative recoveries with good outcomes, and postoperative CTA revealed complete aneurysm clipping without any residual remnants. Conclusions: We were able to perform clipping without removing the ACP in 13 patients (52%), and in 8 of these (32%), the clipping was carried out directly without cutting the FL. Microsurgery, coupled with proximal control of the cervical ICA, can serve as a viable alternative for patients with small dorsal ICA aneurysms, especially when endovascular treatment options are limited, and 3D CTA confirms a clear anatomical relationship with the ACP.

Differences in gross appearance and histopathology of the outer membrane of the subdural hematoma envelope over time: A respective case series and literature review.

RATIONALE: Chronic subdural hematoma (CSDH) is a common disorder among elderly males. The most common theory of its cause is a minor brain injury resulting in the rupture of a bridging vein. The outer membrane of subdural hematoma (SDH) evolves like cutaneous wound healing with different phases. This report aims to use a surgical microscope and an electron microscope to show the pathophysiological differences in the temporal flow of the outer membrane of SDH. PATIENT CONCERNS: This study retrospectively reviewed the cases of 6 patients who underwent craniotomy from 2016 to 2021 at the single center of Chonnam National University Hospital. DIAGNOSES: These patients had a history of intracranial hematoma (ICH) at the surgical site on brain computed tomography (CT) before craniotomy. This study aimed to observe the morphological changes over time in the outer membrane of SDH and analyzed them through macroscopic and pathological findings. INTERVENTIONS AND OUTCOMES: The outer membrane of SDH was confirmed in all six patients who underwent surgery, and macroscopic analysis was performed using an operating microscope. Three patients underwent pathological analysis through histological examination, and through this, the difference according to ICH occurrence and detection time was analyzed. LESSONS: This study suggests that the outer membrane of SDH contains inflammatory and collagen cells in the early stages and thickens over time. This healing response is similar to cutaneous wound healing.

Occipital artery bypass importance in unsuitable superficial temporal artery: Two case reports.

BACKGROUND: Superficial temporal artery-middle cerebral artery (STA-MCA) bypass helps treat cerebral ischemia. However, the STA is not available for bypass in some conditions. Therefore, with some technical tips, the authors introduced a bypass technique using the occipital artery (OA). CASE SUMMARY: Two female patients complained of hemiparesis. Brain magnetic resonance imaging (MRI) indicated contralateral infarction from the MCA steno-occlusion. On Diamox single photon emission computed tomography or perfusion MRI, the contralateral front parietotemporal reserve was diminished. On transfemoral cerebral angiography, the STA was thin with a weak flow; however, the OA was prominent. Direct OA-MCA end-to-side extracranial-intracranial bypass surgery was implemented instead of STA because the caliber was too narrow. The postoperative course was uneventful in both cases, with well-maintained bypass patency and neurological stability during follow-up. CONCLUSION: OA might be an acceptable alternative for MCA cerebral ischemic cases with an unsuitable STA.

Minimally invasive fibrinolytic treatment and drainage in patients with acute subdural hemorrhage and underlying comorbidities.

The incidence of acute subdural hemorrhage (ASDH), which is often caused by head trauma, is steadily increasing due to an increase in the elderly population and the use of anticoagulants. Urgent surgical treatment is recommended if the patient has impaired consciousness, worsening neurological symptoms, or brain midline shift (MLS) due to large hematomas on brain computed tomography (CT). Although large craniotomy is traditionally recommended for ASDH removal, old age, comorbidities, and antiplatelet drugs are considered risk factors for surgical complications, many neurosurgeons hesitate to perform aggressive surgical procedures in these patients. In this study, we introduced a method that can quickly and effectively remove ASDH without general anesthesia. We retrospectively reviewed 11 cases of patients with ASDH who underwent hematoma drainage between June 2019 and December 2020. We measured the maximum subdural hematoma thickness and MLS on brain CT of patients and recorded the Glasgow Coma Scale scores before and after the surgical procedure. All patients had multiple comorbidities, and seven patients received anticoagulant or antiplatelet therapy. On initial brain CT, the median subdural hemorrhage thickness was 21.36 mm, median MLS was 10.09 mm, and mean volume of the subdural hematoma was 163.64 mL. The mean evacuation rate of the subdural hematoma after drainage was 83.57%. There was no rebleeding or operation-related infection during the aspiration procedure, and the median MLS correction after the procedure was 7.0 mm. Our treatment strategies can be a reliable, less invasive, and alternative treatment option for patients at high risk of complications due to general anesthesia or patients who are reluctant to undergo a large craniotomy due to a high bleeding tendency.

Primary cutaneous apocrine carcinoma of the scalp: Two case reports and literature review.

RATIONALE: Apocrine carcinoma is a rare malignant sweat gland tumor that has been reported in approximately 200 cases. This tumor usually occurs in the axilla, but in rare cases, it can also develop in the scalp. In the present work, we report 2 cases of cutaneous apocrine carcinoma of the scalp. PATIENT CONCERNS: Two men visited our outpatient clinic with recurrence of tumor after undergoing surgery for scalp tumor at another hospital. DIAGNOSES: Brain magnetic resonance imaging of a 56-year old man showed the presence of a 5.0 × 4.5 × 4.4 cm scalp mass in the right parietal region, invading the skull and dura mater and a 2.2 × 2.0 × 0.7 cm bony mass without any skin lesions right next to the scalp mass. Neck magnetic resonance imaging of a 76-year-old man revealed the presence of a well-defined oval mass in the subcutaneous layer of the left occipital scalp and 2 enlarged lymph nodes in the left neck. Definite diagnoses were made postoperatively. The patients were diagnosed with cutaneous apocrine carcinoma. The diagnosis was confirmed through histopathological and immunohistochemical staining tests. INTERVENTIONS: The tumors were removed with a wide safety margin and reconstructive surgery was performed. OUTCOMES: Additional radiotherapy or chemotherapy was performed. Follow-up more than 6 months revealed no recurrence or metastasis. LESSONS: If accurate diagnosis and treatment had taken place at the initial stages of the primary cutaneous apocrine carcinoma, it would have been possible to prevent recurrence and intracranial invasion. As recurrent primary cutaneous apocrine carcinoma can become aggressive and difficult to treat, even a small mass on the scalp must be evaluated carefully and treated properly.

Direct Removal of Fourth Ventricle Hematoma in Massive Intraventricular Hemorrhage.

Various grading systems and surgical techniques have been developed for the treatment of intraventricular hemorrhage (IVH); however, little attention has been paid to the fourth ventricle hematoma. Nonetheless, hemorrhagic dilation of the fourth ventricle may lead to catastrophic consequences for patients with massive IVH. We present two cases of massive IVH accompanied by massive fourth ventricle hematoma which was successfully removed with combination of suboccipital craniotomy for fourth ventricle hematoma and intraventricular fibrinolysis for supratentorial hematoma.

A study on the proper catheter position in minimally invasive surgery using stereotactic aspiration plus urokinase for intracerebral hemorrhage.

OBJECTIVE: The surgical method for treating spontaneous intracranial hemorrhage (ICH) is not well established despite ICH's high prevalence and poor prognosis. Minimally invasive surgery has recently received attention; however, literature on this method is scarce. In particular, the appropriate location of the catheter in the hematoma has not been described. We examined whether the catheter position affects the hematoma reduction in a hematoma ＞50 cc. METHODS: We investigated the prognoses of 36 patients with ICH who underwent stereotactic aspiration and hematoma drainage using urokinase from January 2010 to December 2018 and the hematoma reduction rates according to the tube position. Two methods evaluated the position of the catheter. In the first method, the hematoma was an imaginary sphere. The center point was set as the operation target. We evaluated the catheter position by determining whether it was in the deep part or the outer part of the half point from that location to the hematoma margin. In the second method, we evaluated whether the catheter was located 1 cm inside the hematoma margin. RESULTS: In both the first and second evaluations, there were no differences in age, midline shift, intraventricular hemorrhage status, hematoma volume on admission, Glasgow Coma Scale score on admission, time to operation after symptom onset, and systolic blood pressure. The rates of decrease in bleeding and the prognoses were also not significantly different. CONCLUSIONS: If the catheter is in the hematoma, the rate of hematoma reduction at any position is similar.

Real-world evidence on the strategy of olmesartan-based triple single-pill combination in Korean hypertensive patients: a prospective, multicenter, observational study (RESOLVE-PRO).

BACKGROUND: In this prospective, multicenter, non-comparative observational study, the effectiveness and safety of the triple single-pill combination (SPC) of olmesartan/amlodipine/hydrochlorothiazide (OM/AML/HCTZ) were evaluated in a real clinical practice setting in Korean patients with essential hypertension. METHODS: A total of 3752 patients were enrolled and followed for 12 months after administration of OM/AML/HCTZ. Primary endpoint was change from baseline to month 6 in the mean systolic blood pressure (SBP). Secondary endpoints included changes from baseline in the mean SBP at month 3, 9, 12 and the mean diastolic blood pressure (DBP) at month 3, 6, 9, 12; changes in the mean SBP/DBP according to age and underlying risk factors; and blood pressure control rate (%) at different time points. Adherence to and satisfaction with OM/AML/HCTZ treatment among patients and physicians were assessed by medication possession ratio (MPR) and numeric rating scale, respectively, as exploratory endpoints. Safety was evaluated by the incidence and severity of adverse events (AEs) as well as the discontinuation rate due to AEs. RESULTS: OM/AML/HCTZ administration led to significant reductions in the mean SBP/DBP by 11.5/6.6, 12.3/7.0, 12.3/7.2, and 12.8/7.4 mmHg from baseline to month 3, 6, 9 and 12, respectively (P < 0.0001). The BP reductions were maintained throughout the 1-year observation period in all patients with different age groups and risk factors (diabetes mellitus, cardiovascular disease, and renal disease). The BP control rate (%) of < 140/90 mmHg was 65.9, 67.9, 68.9, and 70.6% at month 3, 6, 9, and 12, respectively. The mean MPR during the observation period was 0.96. The safety results were consistent with the previously reported safety profile of OM/AML/HCTZ. CONCLUSIONS: Treatment with the triple SPC of OM/AML/HCTZ demonstrated significant effectiveness in reducing SBP/DBP and achieving target BP control with high adherence over the 1-year observation period in Korean hypertensive patients and was well-tolerated. TRIAL REGISTRATION: CRIS, KCT0002196 , Registered 3 May 2016.

Systemic macrophage depletion attenuates infarct size in an experimental mouse model of stroke.

OBJECTIVE: Macrophages have been shown to play important roles in various pathophysiological processes of the central nervous system via neuroinflammation, leading to an increased interest in macrophage biology. Circulating blood monocytes are among the first cells to infiltrate the brain after ischemic stroke; however, the role of innate immune cells such as monocytes and macrophages remains to be elucidated. Here, we investigated the association between blood monocytes and infarct size following ischemic stroke. METHODS: We induced stroke using a focal ischemia mouse model through middle cerebral artery suture occlusion. To deplete circulating blood monocytes, clodronate was injected intraperitoneally 24 h before the surgery. Animals were sacrificed at specified time points, and the infarct size and mRNA expression were then measured. RESULTS: The clodronate-injected mice showed significantly smaller infarct size than the control mice. Immunohistochemical staining revealed that monocyte depletion significantly blocked the infiltration of macrophages and microglia. The mRNA expression levels of macrophage and microglia markers were higher in the left infarcted brain than in the right non-infarcted brain. CONCLUSIONS: In summary, monocyte depletion reduced the infarct size and mitigated neurological deficits in mice following ischemic stroke, likely by blocking the infiltration of inflammatory cells such as macrophages and microglia.

Correlation between high hair cortisol level and intracranial aneurysm rupture.

ABSTRACT: Measurement of cortisol in hair is a reliable method for determining long-term cortisol exposure reflecting chronic stress. Research using hair cortisol concentration has been limited to mainly cardiometabolic diseases. The association between hair cortisol concentration and aneurysmal rupture has not yet been studied. We aimed to investigate the relationship between the degree of chronic stress as measured by hair cortisol concentration and aneurysmal rupture.Sixty-eight patients diagnosed with intracranial aneurysms were included in this study (ruptured group, 30; unruptured group, 38). Hair cortisol was measured in 3-cm hair segments, reflecting roughly 3 months of hair growth. For a risk factor analysis, patient-specific factors and aneurysm-specific factors as well as hair cortisol concentration were investigated.Hair cortisol concentrations were significantly higher in the ruptured group than in the unruptured group (55.8 ±â€Š22.0 ng/dL vs. 19.1 ±â€Š6.4 ng/dL; P < .001). High hair cortisol concentration was found to be an independent risk factor for aneurysmal rupture (odds ratio [OR]: 2.245, 95% confidence interval [CI]: 1.825-2.753; P = .013). Additionally, a history of cerebrovascular disease was significantly associated with an increased risk of aneurysmal rupture (OR: 1.577, 95% CI: 1.099-2.262; P = .040).Based on our results, we suggest that chronic stress as measured by hair cortisol concentration could be an independent risk factor for intracranial aneurysmal rupture.

Clinical warning signs of life-threatening hematochezia in neurosurgical patients with long-term bed rest: Three cases report.

RATIONALE: Patients with long term bed rest in intensive care unit after neurosurgery could experience splanchnic hypoperfusion. These patients have several other medical conditions that exacerbate splanchnic hypoperfusion during treatment and the splanchnic hypoperfusion could result in "stress-induced intestinal necrosis", which could cause massive hematochezia. We report here the experience of life-threatening hematochezia in 3 patients who underwent brain surgery in our institution. PATIENTS CONCERNS: One female patient (72-year-old) and 2 male patients (58- and 35-year-old) were admitted to our institution because of traumatic intracerebral hemorrhage, subarachnoid hemorrhage due to a ruptured anterior communicating artery, and subarachnoid hemorrhage with unknown cause respectively. All patients underwent emergency brain surgery for diagnosis and treatment. After surgery, they all experienced long-term bed rest in intensive care unit. Hematochezia occurred on postoperative day 15, 17, and 49, respectively. DIAGNOSES: All of the patients were assessed by abdomen/pelvis computed tomography and underwent a colonoscopy. INTERVENTIONS: The female patient underwent embolization through pelvic arteriography and epinephrine injection through colonoscopy, but a total colectomy and ileostomy was performed due to refractory hematochezia. 58-year-old male patient had a laparoscopic ileostomy for the bowel rest. The other patient underwent nil per os and conservative treatment for 2 weeks. OUTCOMES: The female patient was discharged without further treatment plan, 58-year-old male patient survived after laparoscopic ileostomy, while the other patient survived after 2 weeks of nil per os. LESSON: Abdominal symptoms, such as hematochezia, should be actively managed in neurosurgical patients who are undergoing long-term bed rest in an intensive care unit under physiologically stressful medical conditions.

Modified Suturing Techniques in Carotid Endarterectomy for Reducing the Cerebral Ischemic Time.

OBJECTIVE: Carotid endarterectomy (CEA) is an effective surgical procedure for treating symptomatic or asymptomatic patients with carotid stenosis. Many neurosurgeons use a shunt to reduce perioperative ischemic complications. However, the use of shunting is still controversial, and the shunt procedure can cause several complications. In our institution, we used two types of modified arteriotomy suture techniques instead of using a shunt. METHODS: In technique 1, to prevent ischemic complications, we sutured a third of the arteriotomy site from both ends after removing the plaque. Afterward, the unsutured middle third was isolated from the arterial lumen by placing a curved Satinsky clamp. And then, we opened all the clamped carotid arteries before finishing the suture. In technique 2, we sutured the arteriotomy site at the common carotid artery (CCA). We then placed a curved Satinsky clamp crossing from the sutured site to the carotid bifurcation, isolating the unsutured site at the internal carotid artery (ICA). After placing the Satinsky clamp, the CCA and external carotid artery (ECA) were opened to allow blood flow from CCA to ECA. By opening the ECA, ECA collateral flow via ECA-ICA anastomoses could help to reduce cerebral ischemia. RESULTS: The modified suture methods can reduce the cerebral ischemia directly (technique 1) or via using collaterals (technique 2). The modified arteriotomy suture techniques are simple, safe, and applicable to almost all cases of CEA. CONCLUSION: Two modified arteriotomy suture techniques could reduce perioperative ischemic complications by reducing the cerebral ischemic time.

Wedge Resection of the Falx to Clip a Distal Anterior Cerebral Artery Aneurysm.

BACKGROUND: The unilateral anterior interhemispheric approach has been widely used for distal anterior cerebral artery (DACA) aneurysms. However, there are some drawbacks of this approach because of the narrow operative field, including possible brain traction injury, bridging vein injury, and inadequate exposure of the aneurysm. Here, we report a case of a DACA aneurysm covered by the falx that could not be totally exposed with the unilateral interhemispheric approach. We successfully obtained a wide view with wedge resection of the falx, avoiding excessive brain traction and division of the superior sagittal sinus. CASE DESCRIPTION: A 76-year-old woman with a 6-mm unruptured DACA aneurysm underwent a unilateral craniotomy with the anterior interhemispheric approach. In the operative field, the aneurysm was found at the midline, just below the falx. The aneurysm was covered by the falx and could not be completely exposed with the usual brain retraction. Therefore, we performed wedge resection of the falx, thus obtaining sufficient surgical field and totally exposing the aneurysm. We were then able to apply the clip successfully. Postoperative brain computed tomography angiography showed no remnant aneurysm sac or complications of falx resection or brain retraction, such as bleeding or vessel injury. CONCLUSIONS: When an aneurysm is located just below the falx and is exposed inadequately, performing wedge resection of the falx can expose the aneurysms adequately for application of the clip.

Acute Parent Artery Occlusion in Thrombosed Middle Cerebral Artery Aneurysm Presenting with Ischemic Stroke.

BACKGROUND: Thrombosed intracranial aneurysms are complex and unstable lesions that are especially associated with ischemic stroke. Although acute parent artery occlusion manifesting with ischemic stroke is very rare, it can lead to catastrophic consequences. CASE DESCRIPTION: This study presents 2 cases of acute parent artery occlusion in thrombosed large and giant middle cerebral artery bifurcation aneurysms manifesting with ischemic stroke. Both patients were successfully treated with emergent double-barrel superficial temporal artery-to-middle cerebral artery bypass followed by aneurysm trapping. CONCLUSIONS: Emergent superficial temporal artery-to-middle cerebral artery bypass could be a salvageable treatment option in patients with progressive neurologic deficits and significant mismatch between diffusion- and perfusion-weighted imaging in acute parent artery occlusions associated with large or giant thrombosed aneurysms. Besides diffusion- and perfusion-weighted imaging, preoperative assessment of the collaterals will help in predicting postoperative prognosis.

Vasa Vasorum Densities in Human Carotid Atherosclerosis Is Associated with Plaque Development and Vulnerability.

OBJECTIVE: The extensive vasa vasorum network functions as a conduit for the entry of inflammatory cells or factors that promote the progression of angiogenesis and plaque formation. Therefore, we investigated the correlation between the carotid vasa vasorum activities and carotid plaque vulnerability using indocyanine green video angiography (ICG-VA) during carotid endarterectomy (CEA). METHODS: Sixty-nine patients who underwent CEA were enrolled prospectively from September 2015 to December 2017. During CEA, a bolus of ICG was injected intravenously before and after resecting the atheroma. Additionally, we performed immunohistochemistry using CD68 (a surface marker of macrophages), CD117 (a surface marker of mast cells), and CD4 and CD8 (surface markers of T-cells) antibodies to analyze the resected plaque specimens. RESULTS: The density of active vasa vasorum was observed in all patients using ICG-VA. The vasa vasorum externa (VVE) and interna (VVI) were seen in 11 (16%) and 57 patients (82.6%), respectively. Macroscopically, the VVE-type patterns were strongly associated with preoperative angiographic instability (81.8%, p=0.005) and carotid plaque vulnerability (90.9%, p=0.017). In contrast, the VVI-type patterns were weakly associated with angiographic instability (31.6%) and plaque vulnerability (49.1%). CD68-stained macrophages and CD117-stained mast cells were observed more frequently in unstable plaques than in stable plaques (p<0.0001, p=0.002, respectively). CONCLUSION: The early appearance of VVE, along with the presence of many microvessel channels that provided nutrients to the developing and expanding atheroma during ICG-VA, was strongly associated with unstable carotid plaques. The degree of infiltration of macrophages and mast cells is possibly related to the formation of unstable plaques.