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Extremely rarely, the ophthalmic artery (OphA) arises from the A1 segment of the anterior cerebral artery (ACA). Discovery of this anomalous OphA during angiography or surgery has been reported in several patients. We report a case in which an OphA of ACA origin was diagnosed by magnetic resonance (MR) angiography and confirmed by selective cerebral angiography. To our knowledge, this is the first report of this variation with MR angiography. Careful observation of MR angiographic images is important for detecting rare arterial variations. Partial maximum-intensity-projection images are useful in identifying tiny anomalous arteries on MR angiography. [ABSTRACT FROM AUTHOR]

We have realized InP/InGaAs composite-channel metal–oxide–semiconductor field-effect transistors with both selectively regrown n+-InGaAs source/drain regions and Al2O3 as a gate dielectric. A 100-nm-long channel was fabricated by laterally buried regrowth in a channel undercut by metalorganic vapor phase epitaxy. The carrier density of the regrown layer was 2.9×1019 cm-3. A drain current Id of 1.34 mA/µm was achieved at a drain voltage Vd of 1 V and a gate voltage Vg of 3 V. A transconductance gm of 817 µS/µm at Vd = 0.65 V was also observed at the same time. The improvement in the subthreshold slope can be explained by the decrease in dielectric/semiconductor interface trap density. [ABSTRACT FROM AUTHOR]

Background: Carotid webs are a potential cause of occult cerebral infarction. Although they occur frequently, proper diagnosis and treatment are crucial; surgery has been shown to provide a good outcome. Although thrombus on the carotid web have been reported, digital subtraction angiography (DSA)-confirmed cases of pre-dispersed thrombus are rare. In this study, we report a case in which a thrombus on the carotid web concealed a shelf-like defect, complicating its diagnosis., Case Description: A 47-year-old woman without stroke risk factors presented to our hospital with aphasia and right hemiplegia. On arrival, the symptoms had improved. Magnetic resonance (MR) imaging showed left middle cerebral artery stenosis; however, there was no cerebral infarction. DSA was performed post-admission to examine middle cerebral artery stenosis, which showed no middle cerebral artery stenosis but left internal carotid artery (ICA) origin stenosis and contrast pooling. We diagnosed a transient ischemic attack due to artery-to-artery embolism caused by left ICA stenosis and accompanied by a contralateral carotid web. The same symptoms appeared 6 days later. MR imaging showed a new cerebral infarction and the left middle cerebral artery occlusion. A mechanical thrombectomy procedure revealed a change in ICA origin shape compared to the 1 st time, with a shelf-like defect within the carotid web. She subsequently underwent carotid artery stenting and was discharged with mild dysesthesia in her right fingers (modified Rankin Scale of 1)., Conclusion: Thrombus on the carotid web conceals characteristic shelf-like defects and may cause misdiagnosis. However, contrast pooling and contralateral carotid web are important findings for early treatment., Competing Interests: There are no conflicts of interest., (Copyright: © 2024 Surgical Neurology International.)