Spontaneous middle cerebral artery dissection: a series of six cases and literature review.

Middle cerebral artery (MCA) dissection is rare, and various clinical presentations, including hemorrhage, ischemia, or comorbidities, and the changes in imaging findings over time hinder treatment decisions. The European Stroke Organization guidelines exclude MCA dissection. Few cases have been reported with no review of the relevant literature. Therefore, we reviewed the relevant literature and our own experience with non-traumatic MCA dissection cases to determine appropriate treatment strategies. At our institution and affiliated institutions, we encountered six cases of MCA dissection-five with infarction and one with hemorrhage. Two patients underwent revascularization, and one underwent an aneurysmectomy. We reviewed English and Japanese articles in PubMed and Medical Journal Web and summarized the results based on the relationships among age, sex, location, the presence of an aneurysm, the presence of angiography, history, treatment, and mode of onset. The clinical course, changes in imaging, treatment strategies, and prognosis were discussed. Eighty cases were included in the review. Cerebral aneurysms were more common distal to the M2 area (p = 0.00) and were correlated with hemorrhage (p < 0.001). Most hemorrhagic cases with aneurysms were treated surgically, while ischemic cases were treated with antithrombotic agents, and both had a similar neurological prognosis. There were some cases of rebleeding after antithrombotic therapy, especially in older adults.Surgical treatment is recommended in cases of hemorrhage and confirmed aneurysms, particularly for lesions distal to the M2 area. Patients with aneurysm-associated ischemia should be followed up, and antithrombotic treatment should be considered with particular care in older adults.

Vertebral artery V3 portion-radial artery-distal common carotid artery (V3-RA-dCCA) bypass for large basilar trunk aneurysm with bilateral proximal common carotid artery occlusion-technical note.

BACKGROUND: Large basilar trunk aneurysm caused by bilateral occlusion of the proximal common carotid artery is rare. We treated one case with vertebral V3 portion-radial artery-distal common carotid artery (V3-RA-dCCA) bypass. CASE DESCRIPTION: Basilar trunk aneurysm and bilateral occlusion of the proximal CCA were found incidentally in a 70-year-old woman. During the next 5 years, the aneurysm gradually enlarged to 12 mm, and blood flow of the anterior circulation was supplied through the posterior communicating artery. V3-RA-dCCA bypass was performed to reduce the stress of blood flow and prevent aneurysm growth and rupture. After exposing the neck portion, forearm of RA, and V3 portion of the vertebral artery, we created a space just below the sternocleidomastoid muscle to bypass the RA. We flushed the RA with albumin to stiffen the artery and temporarily clamped the bilateral sides of the RA to prevent twisting. We anastomosed the V3 and RA with a 9-0 thread and temporarily clamped the V3. After flushing the RA with albumin to prevent twisting, we clamped the external and internal carotid arteries, opened the dCCA with a vascular punch to prevent arterial dissection, and anastomosed the RA to the dCCA. The patency of the bypass was confirmed with Doppler and indocyanine green video angiography. The postoperative course was uneventful, bypass patency was good, and the aneurysm did not expand further. CONCLUSION: V3-RA-dCCA bypass may be an effective and low-risk treatment for large basilar trunk aneurysms with bilateral occlusion of the proximal common carotid artery.

The mini-combined transpetrosal approach: an anatomical study and comparison with the combined transpetrosal approach.

BACKGROUND: The combined transpetrosal approach (CTPA) is a versatile technique suitable for challenging skull base pathologies. Despite the advantages provided by a wide surgical exposure, the soft tissue trauma, complex and time-consuming bony work, and cosmetic issues make it far from patient expectations. In this study, the authors describe a less invasive modification of the CTPA, the mini-combined transpetrosal approach (mini-CTPA), and perform a quantitative comparison between these two approaches. METHODS: Five human specimens were used for this study. CTPA was performed on one side and mini-CTPA on the opposite side. The surgical freedom, petroclival and brainstem area of exposure, and maneuverability for 6 anatomical targets, provided by the CTPA and mini-CTPA, were calculated and statistically compared. The bony volumes corresponding to each anterior petrosectomy were also measured and compared. Three clinical cases with an operative video are also reported to illustrate the effectiveness of the approach. RESULTS: The question-mark skin incision done along the muscle attachments permits an optimal cosmetic result. Even though the limited incision, the smaller craniotomy, and the less extensive bone drilling of mini-CTPA provide a smaller area of surgical freedom, the areas of exposure of petroclival region and brainstem were not statistically different between the two approaches. The antero-posterior maneuverability for the oculomotor foramen (OF), Meckel's cave (MC) and the REZ of trigeminal nerve, and the supero-inferior maneuverability for OF, MC, Dorello's canal, and REZ of CN VII are significantly reduced by the smaller opening. The bony volume of anterior petrosectomy resulted similar among the approaches. CONCLUSIONS: The mini-CTPA is an interesting alternative to the CTPA, providing comparable surgical exposure both for petroclival region and for brainstem. Although the lesser soft tissue dissection and bony opening decrease the surgical maneuverability, the mini-CTPA may reduce surgical time, potential approach-related morbidities, and improve cosmetic and functional outcomes for the patients.

[Overview and Pitfalls of the Extended Trans:Nasal Endoscopic Approach].

The extended endoscopic endonasal approach(EEA)has been expanding in recent years with the development of instruments and surgical techniques. Basically, sela, extradural, and intranasal lesions such as pituitary tumor, craniopharyngioma, chordoma, chondrosarcoma, and cholesterol granuloma are indicated. Intradural lesions or lesions that extend laterally or downward to the craniocervical junction are more difficult to operate. In addition, cases of hard tumor with calcification of the tumor, cases in which the tumor involves important blood vessels, re-operative cases, and cases after radiotherapy are also difficult cases and should be considered preoperatively. In recent years, we have been trying to keep the nasal structures as much as possible without removing nasal structure, but in cases where the tumor has invaded and destroyed the nasal structures, extended EEA is necessary. The anatomy of the extended EEA is complicated and not common among neurosurgeons. In this chapter, we present the basic anatomy and surgical cases to be understood in extended EEA and explain the pitfalls.

Role of RNF213 polymorphism in defining quasi-moyamoya disease and definitive moyamoya disease.

OBJECTIVE: Quasi-moyamoya disease (QMMD) is moyamoya disease (MMD) associated with additional underlying diseases. Although the ring finger protein 213 (RNF213) c.14576G>A mutation is highly correlated with MMD in the Asian population, its relationship to QMMD is unclear. Therefore, in this study the authors sought to investigate the RNF213 c.14576G>A mutation in the genetic diagnosis and classification of QMMD. METHODS: This case-control study was conducted among four core hospitals. A screening system for the RNF213 c.14576G>A mutation based on high-resolution melting curve analysis was designed. The prevalence of RNF213 c.14576G>A was investigated in 76 patients with MMD and 10 patients with QMMD. RESULTS: There were no significant differences in age, sex, family history, and mode of onset between the two groups. Underlying diseases presenting in patients with QMMD were hyperthyroidism (n = 6), neurofibromatosis type 1 (n = 2), Sjögren's syndrome (n = 1), and meningitis (n =1). The RNF213 c.14576G>A mutation was found in 64 patients (84.2%) with MMD and 8 patients (80%) with QMMD; no significant difference in mutation frequency was observed between cohorts. CONCLUSIONS: There are two forms of QMMD, one in which the vascular abnormality is associated with an underlying disease, and the other in which MMD is coincidentally complicated by an unrelated underlying disease. It has been suggested that the presence or absence of the RNF213 c.14576G>A mutation may be useful in distinguishing between these disease types.

White Matter Lesions as Brain Frailty and Age are Risk Factors for Surgical Clipping of Unruptured Intracranial Aneurysms in the Elderly.

INTRODUCTION: We aimed to identify the risk factors for surgical treatment of unruptured intracranial aneurysms (UIAs) in individuals aged >60 years, particularly focusing on white matter lesions (WMLs). MATERIAL AND METHODS: We investigated a total of 214 patients with UIAs. The patient group comprised 53 males and 151 females with an average age of 68.2 years. UIA size ranged from 2.7 to 26 (mean: 7.3) mm. The primary endpoint of the study was patient prognosis evaluated at the time of discharge using the modified Rankin Scale. We examined the risk factors for poor outcome and WMLs using magnetic resonance imaging. RESULTS: Poor outcome was observed in 23 (10.7%) patients. Significant correlations were observed between poor outcome and UIA size (P < 0.0001), UIAs located posteriorly (P = 0.0204), UIA thrombosis (P = 0.0002), and presence of WMLs (P < 0.0001) in univariate regression analysis. However, no significant correlations were noted between poor outcome and age (P = 0.1438). Multivariate logistic regression analyses showed significant correlations between poor outcome and UIA size (P < 0.0001), presence of WMLs (P = 0.001). Severe WMLs based on the Fazekas classification was correlated to age (P < 0.0001) and atherosclerosis (P = 0.0001). Severe WMLs were associated with ischemia (P < 0.001) and epilepsy (P = 0.0502) as well as length of hospitalization (P < 0.0001). CONCLUSION: Severe WMLs are risk factors for surgical treatment of UIAs in the elderly. Surgical indications must be considered and caution should be taken when managing patients with severe WMLs.

Outcomes in Elderly Japanese Patients Treated for Aneurysmal Subarachnoid Hemorrhage: A Retrospective Nationwide Study.

OBJECTIVE: Japan has the largest elderly population in the world. As data on the clinical outcomes in elderly patients with aneurysmal subarachnoid hemorrhage (aSAH), including those older than 80 years, are lacking, we analyzed the characteristics of 54,805 aSAH patients and recorded their treatments and clinical outcomes using a Japanese nationwide inpatient database. METHODS: Using the Japanese Diagnostic Procedure Combination database, we identified aSAH patients aged 18 years or older who were hospitalized between July 1, 2010 and March 31, 2016. They were categorized as less than or equal to 60-, 61-70-, 71-80-, 81-90-, and greater than or equal to 91 years of age. The primary outcome was the modified Rankin Scale (mRS) score at discharge. Multivariable logistic regression analysis was performed to examine factors affecting the mRS score at discharge. RESULTS: Of 54,805 patients, 37.5% were aged less than or equal to 60 years; 24.8% were 61-70-, 21.8% were 71-80-, 13.9% were 81-90-, and 2.0% were greater than or equal to 91 years old at the time of the insult. Among 46,107 patients younger than 81 years, 58.9% underwent surgical clipping (SC), 22.9% endovascular coiling (EC), and 18.2% were treated conservatively. There were 8,698 patients aged 81 years or older, 32.4% underwent SC, 23.2% EC, and 44.4% were treated conservatively. A poor mRS score (3-6) at discharge was recorded in 87.2% of patients older than 80 years. Multivariable logistic regression was used to compare their estimated odds ratio (OR) for a poor mRS score at discharge with that of patients aged less than or equal to 60 years. The OR increased by 87% in patients between 61 and 70 years of age (P < .001; OR, 1.87; 95% confidence interval (CI), 1.77-1.98), by 358% in patients aged from 71 to 80 years (P < .001; OR, 4.58; 95%CI, 4.29-4.89), by 1,035% in patients between 81 and 90 years (P < .001; OR, 11.35; 95%CI, 10.32-12.49), and by 1,710% in patients aged more than or equal to 91 years (P < .001; OR, 18.10; 95%CI, 13.96-23.46). CONCLUSIONS: As the treatment outcomes in elderly aSAH patients, especially those 80 years old or older, were poor, the appropriate therapy decisions must be made on a case-by-case basis.

Incision of the anterior petroclinoidal fold during clipping for securing the proximal space of an internal carotid artery-posterior communicating artery aneurysm: a technical note.

Surgical clipping of an internal carotid artery (ICA)-posterior communicating artery (ICPC) aneurysm is often difficult in cases involving limited space to insert a clip at the proximal aneurysm neck hidden by the tent. In such cases, we perform incision of the anterior petroclinoidal fold to secure the proximal space for clip insertion. Between April 2013 and March 2018, we treated 89 ICPC aneurysm cases by clipping. Incision of the anterior petroclinoidal fold was performed in 15 of the 89 cases (16.8%). Fast imaging employing steady-state acquisition (FIESTA) magnetic resonance imaging (MRI) can indicate the locations of the aneurysm and tent and can help assess the need for tent incision. We widely dissected the distal sylvian fissure and sufficiently exposed around the aneurysmal space. We coagulated and cut the anterior petroclinoidal fold supra between the ICA and proximal neck of the aneurysm using a low-power bipolar system and needles or micro-scissors with care to avoid injury around structures such as the ICA, aneurysm, and oculomotor nerve. When using this strategy, we often select the Yasargil FT717 clip that has a curve along the skull base because of easy insertion. All cases showed complete aneurysm exclusion on three-dimensional computed tomography angiography, and there was no cerebral infarction, neurological deficit (such as hemiparesis), or oculomotor nerve palsy. Therefore, our strategy of incision of the anterior petroclinoidal fold during clipping for securing the proximal space of an ICA aneurysm is effective and safe.

Efficacy of Thyrotropin-Releasing Hormone Analog for Protracted Disturbance of Consciousness due to Aneurysmal Subarachnoid Hemorrhage.

OBJECTIVE: The efficacy of thyrotropin-releasing hormone tartrate (TRH-T) for treating prolonged disturbance of consciousness due to aneurysmal subarachnoid hemorrhage (SAH) remains unclear. The purpose of the present study was to determine whether TRH-T was really effective, and what was the recovery factor when it was valid. This was a retrospective study of a single facility. METHODS: We treated 208 patients with aneurysmal SAH at our hospital between 2011 and 2017. Among them, we investigated 97 cases in which TRH-T was administered to prolonged disturbance of consciousness. Thirty one patients with Hasegawa dementia rating scale-revised (HDS-R) score less than 20 were included. Patients' HDS-R scores were evaluated 7 days after clipping the aneurysm and 2 days after completing a course of TRH-T treatment. HDS-R score increases of greater than or over equal to 8 and less than 8 were defined as good and poor outcomes, respectively. Outcomes were compared to 11 patients who did not receive TRH-T treatment. RESULTS: Average initial and post-treatment HDS-R scores were 9 ± 6.6 and 19 ± 9.5, respectively. The good outcome group included 19 patients. Statistically significant differences in HDS-R score changes were observed between the group with initial HDS-R scores of 0-4 and the other groups. Poor outcomes were significantly correlated with age of greater than 60 years and initial HDS-R scores less than oroverequal to 4 points. The improvement in HDS-R score was significantly greater in the TRH-T administration group than the control group. CONCLUSIONS: TRH-T was effective for treating prolonged disturbance of consciousness due to aneurysmal SAH, especially in young patients with HDS-R scores between 5 and 20.

Serum Glucose and Potassium Ratio as Risk Factors for Cerebral Vasospasm after Aneurysmal Subarachnoid Hemorrhage.

OBJECTIVE: Cerebral vasospasm is associated with poor prognosis in patients with aneurysmal subarachnoid hemorrhage (SAH), and biomarkers for predicting poor prognosis have not yet been established. We attempted to clarify the relationship between serum glucose/potassium ratio and cerebral vasospasm in patients with aneurysmal SAH. METHODS: We studied 333 of 535 aneurysmal SAH patients treated between 2006 and 2016 (123 males, 210 females; mean age 59.7 years; range 24-93). We retrospectively analyzed the relationship between cerebral vasospasm grade and clinical risk factors, including serum glucose/potassium ratio. RESULTS: Postoperative angiography revealed cerebral vasospasm in 112 patients (33.6%). Significant correlations existed between the ischemic complication due to cerebral vasospasm and glucose/potassium ratio (P < .0001), glucose (P = .016), and potassium (P = .0017). Serum glucose/potassium ratio was elevated in the cerebral vasospasm grade dependent manner (Spearman's r = 0.1207, P = .0279). According to the Glasgow Outcome Scale (GOS) score at discharge, 185 patients (55.5%) had a poor outcome (GOS scores 1-3). Serum glucose/potassium ratio was significantly correlated between poor outcome (GOS scores 1-3) and age (P < .0001), serum glucose/potassium ratio (P < .0001), glucose (P < .0001), potassium (P = .0004), white blood cell count (P = .0012), and cerebral infarction due to cerebral vasospasm (P < .0001). Multivariate logistic regression analyzes showed significant correlations between cerebral infarction due to cerebral vasospasm and serum glucose/potassium ratio (P = .018), glucose (P = .027), and potassium (P = .052). CONCLUSIONS: Serum glucose/potassium ratio in cases of aneurysmal SAH was significantly associated with cerebral infarction due to cerebral vasospasm and GOS at discharge. Therefore, this factor was useful to predict prognosis in patients with cerebral vasospasm and aneurysmal SAH.

Aneurysm Tears Caused by an Aneurysm Clip Springing from the Clip Applier.

We experienced two cases in which aneurysm clips sprang from the applier. In case 1, a subdural haematoma from a ruptured anterior cerebral artery aneurysm was detected. When the clip was opened for final positioning, it suddenly sprang from the applier and ruptured the aneurysm. In case 2, the clip suddenly sprang from the applier as the surgeon opened the applier to clip an unruptured anterior cerebral aneurysm. These accidental phenomena are rare but dangerous. We present these cases to help prevent similar occurrences in the future. Video recordings of actual procedures can point to potential mechanisms and help reduce the incidence of this complication.

Retrograde suction decompression of a large internal carotid aneurysm using a balloon guide catheter combined with a blood-returning circuit and STA-MCA bypass: a technical note.

It is difficult to treat large internal carotid aneurysms with simple surgical clipping. Here, we present a retrograde suction decompression (RSD) procedure for large internal carotid aneurysms using a balloon guide catheter combined with a blood-returning circuit and a superficial temporal artery to middle cerebral artery (STA-MCA) bypass.All patients underwent an STA-MCA bypass before the temporary occlusion of the internal carotid artery (ICA). A 6-French sheath was inserted into the common carotid artery (CCA), and a 6-French Patrive balloon catheter was placed into the ICA 5 cm past the bifurcation. Aneurysm exposure was obtained; temporary clips were placed on the proximal M1, A1, and posterior communicating (Pcom) segments; and an extension tube was then connected to the balloon catheter. A three-way stopcock was placed, and aspiration was performed through the device to collapse the aneurysm. The aspirated blood was returned to a venous line with an added heparin to prevent anemia after aspiration. During the decompression, the blood flow to the cortical area was supplied through the STA-MCA bypass. After the aneurysm collapse, the surgeon carefully dissected the perforating artery from the aneurysm dome or neck, and permanent clips were then placed on the aneurysm neck. Our procedure has several advantages, such as STA-MCA bypass without external carotid artery occlusion for preventing ischemic complications of the cortical area, anemia may be avoided because of the return of the aspirated blood, and a hybrid operation room is not required to perform this method.

The feasibility of detecting cerebral blood flow direction using the indocyanine green video angiography.

The intraoperative confirmation of blood flow direction is necessary in cerebral vascular surgery. Using indocyanine green video angiography (ICG-VAG) with the FLOW 800 system, we examined the transit time of the blood vessel of interest and semiquantitatively evaluated the delay time (T1/2max) from indocyanine green (ICG) injection into the donor artery in reconstructive surgery and the middle cerebral artery (MCA) in aneurysmal surgery. The direction of cerebral blood flow (CBF), which can often be confirmed by ICG-VAG, may be more difficult to determine with faster blood flow. Here, we report our findings regarding the feasibility of detecting CBF direction using the FLOW 800 system. Twenty patients undergoing superficial temporal artery (STA) to MCA anastomosis for carotid occlusive disease and 13 patients with a small MCA aneurysm clipping were evaluated using the T1/2max, semiquantitative method with the FLOW 800 system. In STA-MCA anastomosis cases, the regions of interest (ROIs) included: the proximal donor STA and a region more than 10 mm on the distal side of the donor STA near the anastomosis site. In MCA aneurysms, the ROIs included the proximal M1 and distal M2 sides of the MCA aneurysm. T1/2max was significantly shorter for the proximal sites compared to the distal sites for all subjects (ps < 0.01). T1/2max was shorter for all subjects in the proximal sites. The direction of CBF can be determined using the FLOW 800 system.

Long-term patency of superficial temporal artery to middle cerebral artery bypass for cerebral atherosclerotic disease: factors determining the bypass patent.

Long-term patency of superficial temporal artery to middle cerebral artery (STA-MCA) bypass surgery for atherosclerotic disease and associated risk factors for loss of patency have rarely been discussed. We retrospectively analyzed long-term patency following STA-MCA bypass and evaluated various demographic and clinical factors to identify the ones predictive of postsurgical loss of patency using records of 84 revascularization procedures (58 patients, 45 males; mean age at surgery 63.6 years, range 31-78 years). Bypass patency was diagnosed based on magnetic resonance angiography or three-dimensional computed tomography. The mean follow-up period was 24.7 months (range 6-63 months). Decreased bypass patency was observed in 4 of 58 patients (6.9 %) who collectively underwent 6 bypasses (7.1 %) of 84. All cases of decreased bypass patency were first detected within 6 months of surgery. Bypass patency was not correlated with age, sex, number of anastomoses, postoperative cerebral infarction, or control of postoperative diabetes mellitus. We found a significant association of bypass patency with hyperperfusion (p = 0.01) and postoperative smoking (p = 0.0036). Furthermore, we found a significant association of hyperperfusion with STA diameter (p < 0.0001), location of anastomosis (p = 0.075), and preoperative cerebral blood flow (p = 0.0399). In our retrospective study, hyperperfusion and smoking after surgery may be risk factors for decreased bypass patency in cerebral atherosclerotic disease patients. Careful monitoring of patency to prevent hyperperfusion and cessation of smoking are recommended, particularly within 6 months of the surgery.

Olfactory preservation during anterior interhemispheric approach for anterior skull base lesions: technical note.

Anosmia is not a rare complication of surgeries that employ the anterior interhemispheric approach. Here, we present a fibrin-gelatin fixation method that provides reinforcement and moisture to help preserve the olfactory nerve when using the anterior interhemispheric approach and describe the results and outcomes of this technique. We analyze the outcomes with this technique in 45 patients who undergo surgery for aneurysms, brain tumors, or other pathologies via the anterior interhemispheric approach. Anosmia occurred in 4 patients (8.8%); it was transient in 2 (4.4%) and permanent in the remaining 2 (4.4%). Brain tumors clearly attached to the olfactory nerve were resected in the patients with permanent anosmia. We found a significant difference in the presence of anosmia between patients with or without lesions that were attaching the olfactory nerve (p = 0.011). Our results suggested that fibrin-gelatin fixation method can reduce the reported risk of anosmia. However, the possibility of olfactory nerve damage is relatively high when operating on brain tumors attaching olfactory nerve.

Endocan, a new invasion and angiogenesis marker of pituitary adenomas.

Angiogenesis plays a crucial role in tumor growth. Recently, endocan has emerged as a new marker of vascular endothelial cells from cancers in other organs. In this study, we elucidated the relationship between endocan expression and tumor invasion of pituitary adenoma. Tumor tissues were obtained from 70 patients with pituitary adenoma and were examined using fluorescence immunohistochemistry. Tissue samples included 4 adrenocorticotrophic hormone producing adenomas, 10 growth hormone-producing adenomas, 49 clinically nonfunctioning adenomas, 6 prolactin producing adenomas, and 1 thyroid-stimulating hormone producing adenoma. Endocan was exclusively expressed in CD34-positive vascular endothelial cells, with over 90 % colocalization. The CD34 expression was significantly elevated with endocan expression (linear regression slope, 1.200; r(2) = 0.268, F = 23.08, p < 0.0001). As a percentage of CD34 expression, endocan expression was elevated in a Knosp grading dependent manner (Spearman's r-value, 0.651; p < 0.0001), and was also significantly elevated in macroadenomas compared with microadenomas (p = 0.0133). However, no differences in endocan expression were observed between hormonal subtypes (p = 0.066; Kruskal-Wallis test), age (Spearman's rank correlation test, p = 0.4909), or sex (Mann-Whitney test, p = 0.1701). These data show that endocan is closely related to tumor angiogenesis, and may predict tumor invasion into neighboring cavernous sinuses in pituitary adenomas.

Pathophysiology and management of intracranial arterial stenosis around the circle of Willis associated with hyperthyroidism: case reports and literature review.

Cases of moyamoya disease or intracranial arterial stenosis around the circle of Willis (M/IAS) associated with hyperthyroidism have been reported. However, most of these previous reports were of the ischemic form of M/IAS and primary hyperthyroidism. To the best of our knowledge, no studies have documented therapy for M/IAS associated with hyperthyroidism. We discuss four previously unreported cases, including those involving the intracerebral hemorrhage form and thyroid-stimulating hormone (TSH) secretion from a pituitary adenoma (secondary hyperthyroidism). We analyzed data from 52 previously reported cases, including the 4 cases presented here, and discuss M/IAS associated with hyperthyroidism, treatment options, pathophysiology, the ischemic and hemorrhagic forms, secondary hyperthyroidism, and the relevant literature. Hyperthyroidism results in thyrotoxicosis and the stimulation of the superior cervical ganglion by TSH antibodies and f-T3/f-T4. Consequently, hypercoagulability and stenosis of the cerebral artery can occur. There are many reports of ischemic M/IAS associated with hyperthyroidism. A conservative approach to treatment is important in such cases; for example, antithyroid therapy should be the first choice to treat ischemic M/IAS. There have been only a limited number of reports on hemorrhagic M/IAS. We presume that hemorrhagic M/IAS tears the weakened vasculature in a manner similar to that of normal M/IAS (with no complicating hyperthyroidism). The authors also reported M/IAS associated with secondary hyperthyroidism due to pituitary thyroid secreting hormone secreting adenoma.

Experience Using Gentian Violet-Free Dyes for Tissue Visualization.

BACKGROUND: Gentian violet ink is used as a skin marker in various surgical procedures, including neurosurgery. The dye is also used to visualize the edges of blood vessels during bypass surgery. However, gentian violet ink carries the risks of carcinogenicity and venous injury, which causes microvascular thrombosis. In this study, we compare the gentian violet-free dye C.I. Basic Violet 4 (BV4) and gentian violet. The usefulness, in terms of color, and formation of microvascular thrombosis in anastomosis were compared. METHODS: We used the gentian violet-free dye in 20 cases involving 3 vascular anastomoses. The bone cutting lines on the bone surface, superior temporal artery, and middle cerebral artery were drawn using BV4 and gentian violet ink. RESULTS: The colors of BV4 and gentian violet ink were similar. No thrombus formation was observed at the vascular anastomosis when using BV4. CONCLUSION: BV4 can be used similarly to gentian violet ink. No adverse effects such as thrombus formation in microvascular anastomosis were experienced when BV4 was used.

Pathological Findings of Donor Vessels in Bypass Surgery.

(1) Background Cerebral revascularization is necessary to treat intracranial arterial stenosis caused by moyamoya disease, atherosclerosis, or large complex aneurysms. Although various donor vascular harvesting methods have been reported safe, there are no reports on the histological evaluation of donor vessels for each disease, despite the variety of diseases wherein vascular anastomosis is required. (2) Methods Pathological findings of the superficial temporal artery (STA), radial artery (RA), occipital artery (OA), and saphenous vein (SV) harvested at the institution were analyzed. Patients classified according to aneurysm, atherosclerosis, and moyamoya disease were assessed for pathological abnormalities, medical history, age, sex, smoking, and postoperative anastomosis patency. (3) Results There were 38 cases of atherosclerosis, 15 cases of moyamoya disease, and 30 cases of aneurysm in 98 donor vessels (mean age 57.2) taken after 2006. Of the 84 STA, 11 RA, 2 OA, and 1 SV arteries that were harvested, 71.4% had atherosclerosis, 11.2% had dissection, and 10.2% had inflammation. There was no significant difference in the proportion of pathological findings according to the disease. A history of hypertension is associated with atherosclerosis in donor vessels. (4) Conclusions This is the first study to histologically evaluate the pathological findings of donor vessels according to disease. The proportion of dissection findings indicative of vascular damage due to surgical manipulation was not statistically different between the different conditions.

RNF213-Related Vasculopathy: Various Systemic Vascular Diseases Involving RNF213 Gene Mutations: Review.

Moyamoya disease (MMD) is a cerebrovascular disorder that is predominantly observed in women of East Asian descent, and is characterized by progressive stenosis of the internal carotid artery, beginning in early childhood, and a distinctive network of collateral vessels known as "moyamoya vessels" in the basal ganglia. Additionally, a prevalent genetic variant found in most MMD cases is the p.R4810K polymorphism of RNF213 on chromosome 17q25.3. Recent studies have revealed that RNF213 mutations are associated not only with MMD, but also with other systemic vascular disorders, including intracranial atherosclerosis and systemic vascular abnormalities such as pulmonary artery stenosis and coronary artery diseases. Therefore, the concept of "RNF213-related vasculopathy" has been proposed. This review focuses on polymorphisms in the RNF213 gene and describes a wide range of clinical and genetic phenotypes associated with RNF213-related vasculopathy. The RNF213 gene has been suggested to play an important role in the pathogenesis of vascular diseases and developing new therapies. Therefore, further research and knowledge sharing through collaboration between clinicians and researchers are required.