Elucidating the multiple genetic alterations involved in the malignant transformation of a KRAS mutant neurenteric cyst. A case report.

Neurenteric cyst (NC) shows benign histopathology and rarely demonstrate malignant transformation. We herein describe a case of NC that exhibited malignant transformation. A 65-year-old female presented with gait disturbance due to compression by a cystic mass on the dorsal surface of the medulla oblongata. Partial resection was performed twice, leading to improvement of her symptoms. Two years after the second surgery, gadolinium-perfused T1-weighted magnetic resonance imaging revealed an invasive lesion with contrast enhancement at the trigone of the left lateral ventricle for which partial resection followed by radiotherapy was performed. However, mass regrowth was observed, with the patient eventually succumbing to her disease 11 months after her third surgery. Histopathological analyses of the first and second surgical specimens identified pseudostratified cuboidal epithelial cells, with no nuclear or cellular atypia resembling gastrointestinal mucosa, lining the inner surface of the cystic wall. Based on these findings the lesion was diagnosed as NC. The third surgical specimen exhibited apparent malignant features of the epithelial cells with elongated and hyperchromatic nuclei, several mitotic figures, small necrotic foci, and a patternless or sheet-like arrangement. Based on these findings, the lesion was diagnosed as NC with malignant transformation. Next-generation sequencing revealed KRAS p.G12D mutation in all specimens. Additionally, the third surgical specimen harbored the following 12 de novo gene alterations: ARID1A loss, BAP1 p.F170L, CDKN1B loss, CDKN2A loss, CDKN2B loss, FLCN loss, PTCH1 loss, PTEN loss, PTPRD loss, SUFU loss, TP53 loss, and TSC1 loss. The aforementioned results suggest that KRAS mutation is associated with the development of the NC, and that the additional gene alterations contribute to malignant transformation of the NC.

Efficacy of Emergency Room Skip Strategy in Patients Transferred for Mechanical Thrombectomy.

Objective: Time to recanalization is directly linked to cerebral infarction prognosis. However, patients transferred from another hospital take longer to arrive than those transported directly. To minimize time to recanalization, the emergency room (ER) skip strategy for hospital transfers was executed and reviewed. Methods: From April 2019, patients transferred from another hospital for mechanical thrombectomy were carried into the angio-suite using emergency service stretchers. Results for these patients (ER skip group) were compared with those for patients transported directly to our hospital (Direct group). Results: Among 108 cases in 32 months, 99 patients (91.7%) had major cerebral artery occlusion and underwent endovascular treatment. No differences in age, baseline National Institutes of Health Stroke Scale score, effective recanalization rate, or proportion of posterior circulation cases were seen between groups. The ER skip group (26 patients) showed significantly longer median time from onset to arrival (240 vs. 120 min; p = 0.0001) and significantly shorter median time from arrival to groin puncture (11 vs. 69 min; p = 0.0000). No significant differences were evident in time from groin puncture to recanalization (39 vs. 45 min), time from onset to recanalization (298 vs. 244 min), or rate of modified Rankin Scale score 0-2 after 90 days (42.3% vs. 32.9%). Median time from alarm to recanalization (266 vs. 176 min; p = 0.0001) was significantly longer in the ER skip group. Door-to-puncture (DTP) time for the Direct group gradually fell as the number of cases increased, reaching 40 min by the end of study period. In contrast, DTP time for the ER skip group remained extremely short and did not change further. The proportion of patients who underwent both CT and MRI before endovascular treatment was significantly lower in the Direct group (30.1%) than in the ER skip group (57.7%). In the ER skip group, median length of stay in the primary hospital was 119 min, and the median duration of interhospital transfer was 16 min. Conclusion: The ER skip strategy for patients transferred with large vessel occlusion achieved favorable outcomes comparable to that for direct transport cases. Direct transport to a thrombectomy-capable stroke center remains ideal, however, because the time to intervention is improving for direct transport cases each year.

Retrograde T-Stent Technique for Large, Wide-Necked Internal Carotid-Posterior Communicating Artery Aneurysm.

Objective: We report a case of a wide-necked internal carotid-posterior communicating (IC-Pcom) artery aneurysm treated by the retrograde T-stent technique in which a stent was also placed in the Pcom artery via the posterior circulation. Case Presentation: A 35-year-old woman was diagnosed with an unruptured right IC-Pcom artery aneurysm (maximum diameter: 11 mm, neck diameter: 8.5 mm) during a detailed examination for vertigo. The Pcom artery (2.1 mm) branched from the aneurysmal dome. A microcatheter was guided in retrograde via the Pcom artery from the posterior circulation. A low-profile visualized intraluminal support (LVIS) Jr. 2.5 mm × 17 mm was deployed from the internal carotid artery (ICA) to the Pcom artery, and then, an LVIS 4.5 mm × 23 mm was deployed while pressing the flare of the LVIS Jr. protruding into the ICA. T configuration stenting was completed, and the coil was inserted as tightly as possible. Conclusion: The retrograde T-stent technique, which has the advantage of optimal stent positioning, is useful for preserving a Pcom artery branching from the aneurysmal dome.

Unilateral oculomotor nerve palsy caused by arterial compression accompanying subarachnoid hemorrhage: a case report.

Unilateral oculomotor nerve palsy, often caused by aneurysmal compression, is one of the decisive findings for confirming the site of a ruptured aneurysm. However, arterial compression can also cause unilateral oculomotor nerve palsy. Here, we present the case of a 59-year-old woman with a ruptured right internal carotid-posterior communicating artery aneurysm accompanied by contralateral oculomotor nerve palsy. The nerve was found to be compressed by the posterior cerebral artery and was isolated from the ruptured aneurysm. When confirming a ruptured aneurysm based on the evidence of unilateral oculomotor palsy, the arteries surrounding the nerve must be thoroughly assessed.

Safety and feasibility of the distal transradial approach: A novel technique for diagnostic cerebral angiography.

PURPOSE: We aimed to evaluate the safety and feasibility of the distal transradial approach (DTRA) as a novel technique for cerebral angiography based on our institutional initial experience. METHODS: We retrospectively analyzed our institutional database of consecutive diagnostic cerebral angiographies performed with DTRA from December 2018 to August 2019. Patient demographics and clinical and procedural data were recorded. RESULTS: In total, 51 diagnostic cerebral angiographies in 51 patients (age, 15-83 years; mean age, 59.4 years, SD 13.5; 35 (69%) females) were performed or attempted with DTRA. Ultrasound evaluation showed that the mean inner distal radial artery diameter was significantly smaller than the mean inner forearm radial artery diameter (2.19 mm vs. 2.56 mm, P < 0.001). Cannulation via the distal radial artery was successful in 47 (92%) procedures. In the four procedures that failed, operators converted to the ipsilateral transradial approach without repositioning or redraping. Selective catheterization of the intended vessel was achieved in 64 (91%) of 70 vessels. In the remaining six, operators achieved the objective of the examination with angiography injecting from proximal and conversion to another approach was not required. One patient experienced temporary numbness around the puncture site after the procedure. No radial artery occlusion was identified in the patients who underwent ultrasound evaluation. CONCLUSION: Our results demonstrate that DTRA could become a standard approach for diagnostic cerebral angiography owing to the low complication rate and the high cannulation success rate.

[Bilateral Internal Carotid Artery Dissection Caused by Elongated Styloid Processes:A Case Report].

We report a case of bilateral internal carotid artery(ICA)dissection associated with bilateral elongated styloid processes(ESPs). A 46-year-old man presented with transient aphasia and left visual disturbance at a business meeting. He complained of a foreign body sensation in his throat during swallowing for two years. Magnetic resonance imaging(MRI)demonstrated fresh small infarcts in the left corona radiata. Magnetic resonance angiography(MRA)revealed string signs bilaterally in the cervical ICAs. The patient was diagnosed with bilateral idiopathic ICA dissection and was treated with ozagrel and clopidogrel. Three-dimensional computed tomographic angiogram(3DCTA)indicated bilateral ESPs and bilateral ICA stenosis. 3DCTA with the patient's head tilting and neck extension revealed that each ICA was compressed by the ipsilateral ESP. A follow-up MRA showed complete normalization of bilateral ICAs after neck rest and anti-platelet therapy, following which, clopidogrel was stopped. The patient wore a soft cervical collar until the operation, to avoid contact between the ESPs and ICAs due to changes in head position. Bilateral ESP resection was performed to prevent recurrence of cerebral ischemic events caused by ICA dissection. The patient was discharged one week after the surgery without any neurological deficit. There was no recurrence of symptoms during the next eight months after the operation.