Unusually elongated superior thyroid cornu associated with recurrent cerebral embolisms.

The superior thyroid cornu (STC) is a normal anatomic structure that forms part of the thyroid cartilage. Here, we report a patient with unusually elongated and ossified STC that might result in recurrent cerebral embolisms. During a second endovascular therapy for recurrent middle cerebral artery embolism, a segment with an irregular filling defect was noted in the internal carotid artery (ICA), at the C1 level. This defect was unnoticed during the initial endovascular procedure. Three-dimensional computed tomography angiography performed after the second endovascular procedure revealed an ICA segment located between the STC and C1 with a tortuous course and irregular wall of the ICA. Therefore, we assumed that STC compression of the ICA could have resulted in thrombus formation at the site and consequent cerebral embolism. The STC should be considered a structure responsible for cerebral embolism. Careful evaluation of the entire ICA course is imperative prior to performing an endovascular thrombectomy for acute embolic occlusion of the middle cerebral artery.

Older age, carotid artery stenosis, and female sex as factors correlated with twisted carotid bifurcation based on 457 angiographic studies.

BACKGROUND: Twisted carotid bifurcation (TCB) is a well-known anatomical variation of the carotid bifurcation in patients undergoing carotid endarterectomy. However, few investigations of TCB have focused on patients without internal carotid artery (ICA) stenosis. This study was performed to analyze the characteristics of TCB in patients with ICA stenosis and other diverse pathologies. METHODS: All conventional cerebral angiographies performed in our institute for any reason from January 2012 to December 2018 were reviewed. The patients were divided into two groups, the TCB group and the anatomically normal non-TCB group, and the basic characteristics of the groups were analyzed. RESULTS: Both sides of the carotid bifurcation were clearly visualized in 457 patients. TCB was found in 89 of 457 patients (19.5%); among these 89 patients, 74 (83.1%) had TCB only on the right side, 8 (9.0%) only on the left side, and 7 (7.9%) bilaterally. TCB was found more frequently on the right than left [81 (17.7%) and 15 (3.3%), respectively, on each of the 457 sides (p < 0.0001)]. TCB was significantly more frequent in older patients (p = 0.02), female patients (p < 0.001), and patients with ICA stenosis or occlusion at the bifurcation (p = 0.005). The prevalence of TCB was 19.5%, and 84.4% of cases were on the right side in patients with diverse pathologies. CONCLUSIONS: Older patients, female patients, and patients with ICA stenosis or occlusion are more prone to have TCB.

Ruptured anomalous hyperplastic anterior choroidal artery aneurysm: a case report.

A 48-year-old man hospitalized for subarachnoid hemorrhage harbored a ruptured aneurysm arising from an anomalous hyperplastic anterior choroidal artery. Endovascular treatment was performed and the aneurysm was successfully embolized with neck remnant. The anterior choroidal artery is a very important artery supplying critical brain structures in the treatment of intracranial vascular disease. Anomalous hyperplastic anterior choroidal artery is rare, so the embryological perspective is important for its recognition in surgical procedures.

Cholesterol Crystals in the Retrieved Thrombus by Mechanical Thrombectomy for Cerebral Embolism: A Case Report and Literature Review.

There are only a few case reports in which cholesterol crystals were found in the thrombus retrieved by mechanical thrombectomy for cryptogenic stroke, leading to a definitive diagnosis. We herein report a case of aortogenic embolic stroke diagnosed by the presence of rich cholesterol crystals in the retrieved thrombus and review the previously reported cases. A woman in her 80s was transferred as an emergency due to consciousness disturbance, right conjugate deviation, and severe left hemiparesis. Magnetic resonance imaging showed occlusion of the right middle cerebral artery (MCA) and acute infarction in the territory. The MCA was recanalized by thrombectomy using an aspiration catheter and stent retriever, and the symptoms improved. Although the physiological examination did not detect the embolic source during hospitalization, pathological examination of the thrombus revealed atheroma with numerous cholesterol crystal clefts and intermixing of fibrin. Contrast-enhanced computed tomography performed based on the pathological results showed atheromatous lesions in the aortic arch as the embolic source. As a subsequent treatment, medications of a strong statin and an antiplatelet agent were continued, and the patient had no recurrence. The finding that the retrieved thrombus is a simple atheroma containing cholesterol crystals with poor hemocytes suggests embolism due to plaque rupture. Pathological examination of the thrombus obtained by thrombectomy is one of the useful diagnostic approaches for stroke etiology and the determination of its treatment.

A Case of Vertebral Artery Dissecting Aneurysm with Double Origin of the Posterior Inferior Cerebellar Artery Causing Subarachnoid Hemorrhage.

Double origin of the posterior inferior cerebellar artery (DOPICA) is rare but is associated with intracranial aneurysm formation. A 46-year-old man was brought to our hospital with severe subarachnoid hemorrhage (SAH). Digital subtraction angiography revealed right vertebral artery dissecting aneurysm (VADA) and DOPICA. The aneurysm involved the distal component of the posterior inferior cerebellar artery. The proximal component covered the original flow angiographically. Endovascular internal trapping and parent artery occlusion were performed for the aneurysm and the right vertebral artery (VA). Flow of the posterior inferior cerebellar artery was preserved by the proximal component of the posterior inferior cerebellar artery after trapping. The patient unfortunately died and autopsy revealed ischemic change in the right medulla oblongata. The ischemic change was considered to occur at the treatment according to the pathological findings. Sacrifice of one component of DOPICA to treat VADA with the expectation of preserved flow via the other component should be considered cautiously in terms of the neurovascular anatomy.

Surgical Results of Carotid Endarterectomy for Twisted Carotid Bifurcation.

BACKGROUND: The internal carotid artery is normally positioned posterolateral to the external carotid artery at the carotid bifurcation. An anatomic variation with the internal carotid artery positioned medial to the external carotid artery, the so-called twisted carotid bifurcation (TCB), is sometimes encountered in patients undergoing carotid endarterectomy (CEA). Little is known about the TCB or the implications for CEA. OBJECTIVE: The present study investigated the demographics and surgical results of our patients with TCB who underwent CEA, and demonstrates the surgery in a video clip. METHODS: Eleven of our series of 73 consecutive CEA patients (15.1%) had a TCB (TCB group). The basic surgical method was the same for both the TCB and non-TCB groups. RESULTS: The patient demographics were almost identical between the 2 groups. No significant difference was observed in the degree of stenosis, the duration of operation, or the surgery-related complications between the 2 groups. However, 9 of 11 cases were right-sided in the TCB group; the only significant difference between the groups. CONCLUSIONS: CEA for TCB can be safely performed by extension of the normal procedure, but with more meticulous preoperative assessment and gentle maneuvers. The reason for the right-side dominance is still unknown. Further investigation is needed of this anatomic entity.

Bipolar Cutting Method: Another Technique for Harvesting Donor Artery With Histological Investigation.

BACKGROUND: Safe and appropriate harvesting of the donor scalp vessel is the first key procedure in any type of bypass surgery. OBJECTIVE: To use the so-called bipolar cutting method to harvest donor arteries, in which the donor arteries are skeletonized with bipolar cautery. The surgical procedure and the preparation of the equipment of the bipolar cutting method are described. The surgical results and histological assessment are presented. METHODS: The bipolar generator was set at 50 Malis units in the coagulation mode. Under the surgical microscope, the surrounding tissue of the donor artery was divided and coagulated with the bipolar forceps. The donor artery was completely skeletonized to provide adequate length. After the recipient artery was chosen and the anastomosis site was decided, the distal end of the donor artery was cut to the appropriate length. The remnant fragment of the donor artery was histologically investigated for any damage to the arterial wall. The specimen was cut longitudinally to observe the entire length of the arterial wall and stained with hematoxylin and eosin and elastica van Gieson. RESULTS: A total of 30 bypass surgeries were performed and 38 histological specimens were obtained between February 2015 and June 2016. The success rate of the bypass was 96%. No arterial wall damage such as thermal injury or dissection of the wall was recognized in any of the specimens. CONCLUSION: The bipolar cutting method is a useful and safe method for harvesting donor scalp artery.

Posterior auricular artery-middle cerebral artery bypass: a rare superficial temporal artery variant with well-developed posterior auricular artery-case report.

The posterior auricular artery (PAA) is one of the branches of the external carotid artery, but is usually too small for use as a donor artery for middle cerebral artery (MCA) territory revascularization. An extremely unusual case of PAA-MCA anastomosis was performed in a patient requiring MCA territory revascularization because the superficial temporal artery (STA) parietal branch was absent and the PAA was large enough. A 65-year-old man developed mild motor weakness in the right extremities caused by multiple small infarctions. Single photon emission computed tomography (CT) revealed deterioration of the vascular reserve capacity in the left MCA area. Cerebral angiography showed severe stenosis in the C2 portion of the left internal carotid artery, absence of the parietal branch of the left STA, and a well-developed PAA extending to the parietal area. The patient underwent STA (frontal branch)-MCA and PAA-MCA double anastomosis, and has suffered no stroke or transient ischemic attack. The STA with no bifurcation is known as a rare variation. The PAA also occurs with size variations but well-developed PAA is thought to be extremely rare. PAA can be used as a donor artery for MCA territory revascularization if the vessel size is suitable. Preoperative evaluation of the anatomy is mandatory for harvesting the arteries.

Environmental polarity estimation in living cells by use of quinoxaline-based full-colored solvatochromic fluorophore PQX and its derivatives.

Fluorosolvatochromic probes have recently attracted interest for live cell imaging. We recently tested our quinoxaline-based fluorosolvatochromic probes, PQX and MPQX, for in vivo imaging applications. PQX and MPQX are characterized by donor (pyrrole site)-acceptor (quinoxaline site) structure, and the peak emission wavelength of these compounds varies over the visible wavelength range depending on the polarity of the solvent used, for a variety of solvents from hexane to water. A linear relationship was obtained between peak emission wavenumber and E(T)(N) (normalized solvent polarity). When tested on cultured HEp-2 cells, the results showed that the PQX and MPQX were not harmful at the applied concentrations (10(-5) M), and site-dependent fluorescence spectra in living cells were observed with PQX treatment, which indicates that PQX penetrates into the plasma membrane, followed by delocalization throughout the cells. MPQX was also able to penetrate the cell membrane, distribute throughout the cells and emit fluorescence, but did not show site-dependent intracellular fluorescence spectra. These results suggest that PQX is a remarkable tool for investigating the local polarity environment in cells after appropriate conjugation to biomolecules.

Development of a quinoxaline-based fluorescent probe for quantitative estimation of protein binding site polarity.

The compound 2-[(1E)-2-(1H-pyrrol-2-yl)ethenyl]-quinoxaline (PQX) is a promising fluorescent chromophore for the estimation of protein binding site polarity, due to its full-color solvatochromic fluorescence. A linear relationship was obtained between the peak emission wavenumber and E(T)(N) (normalized solvent polarity). The BSA binding site polarity was estimated from the solvatochromic plot.

Pleural malignant mesothelioma causing cord infiltration through the nerve root. Case report.

A 61-year-old man presented with a rare pleural malignant mesothelioma of the spine manifesting as progressive weakness of the bilateral lower extremities, numbness in the body and both legs, and dysfunction of the bladder and bowel. He had previous occupational exposure to asbestos while working at a car repair shop and had undergone right panpleuropneumonectomy under a diagnosis of sarcomatous type mesothelioma in the right pleural space. Magnetic resonance imaging of the spine with gadolinium showed an enhanced intramedullary tumor at the T4 level. Operative findings disclosed the clouded and swollen right posterior nerve root, and the pial surface was covered by clouded arachnoid-like membrane. The removed part of the T4 posterior nerve root and intramedullary tumor revealed malignant mesothelioma with invasion spreading along the posterior nerve root. He died of respiratory failure 3 months after the diagnosis. This case shows that spinal metastasis must be considered if a patient with pleural malignant mesothelioma shows neurological worsening and neuroimaging shows an abnormal lesion in the thoracic spinal cord. However, the patient's neurological condition is very difficult to improve in the presence of spinal cord infiltration.

Orbital dermoid cyst with intratumoral inflammatory hemorrhage: case report.

An 85-year-old female presented with a 3-month history of worsening hyperlacrimation and blurred vision following blunt head injury. Her past medical history was unremarkable. Her blood examination identified no abnormal findings. Neuroophthalmological inspection revealed extraocular movement disorder and mild exophthalmos on the affected side. Her visual acuity was not disturbed. Neuroimaging showed a cystic mass located extraconally in the superolateral compartment of the anterior orbit, without enhancement by contrast medium. Surgical exploration resulted in escape of chocolate-colored, liquefied hematoma during dissection. No vascular lesion was found. A grayish-white cyst wall was found adhering strongly to the lateral and superior rectus muscles. The lacrimal gland was not identified. The mass was totally resected. Histological examination indicated dermoid cyst with inflammatory interstitial hemorrhage. No component of vascular malformation or atypia was found. Hyperlacrimation and extraocular movement improved postoperatively. We thought that the previous blunt head injury might have induced intratumoral hemorrhage in the preexisting dermoid cyst and that the escaped contents caused inflammatory irritation, resulting in the hyperlacrimation. Dermoid cyst may show atypical presentation with intratumoral hemorrhage and should always be included in the differential diagnosis of orbital tumor.

Repetitive transcranial magnetic stimulation induces kf-1 expression in the rat brain.

Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive approach used for stimulating the brain, and has proven effective in the treatment of depression, however the mechanism of its antidepressant action is unknown. Recently, we have reported the induction of kf-1 in rat frontal cortex and hippocampus after chronic antidepressant treatment and repeated electroconvulsive treatment (ECT). In this study, we demonstrated the induction of kf-1 after rTMS in the rat frontal cortex and hippocampus, but not in hypothalamus. Our data suggest that kf-1 may be a common functional molecule that is increased after antidepressant treatment, ECT and rTMS. In conclusion, it is proposed that induction of kf-1 may be associated with the treatment induced adaptive neural plasticity in the brain, which is a long-term target for their antidepressant action.