Erratum to "Crossing double stent retriever technique for refractory terminal internal carotid artery occlusion" [Radiology Case Reports 17 (2022) 1848-1852].

[This corrects the article DOI: 10.1016/j.radcr.2022.03.023.].

Acute internal carotid artery occlusion due to dissection of the paraclinoid segment: Diagnostic usefulness of angiographic findings during stent retriever deployment.

Intracranial artery dissection is an uncommon but possible cause of ischemic stroke, and is usually diagnosed based on imaging findings such as mural hematoma and dissection flap. However, it is challenging to recognize the underlying dissection in cases of acute large vessel occlusion. In this report, we present a case of acute internal carotid artery occlusion, in which the underlying dissection of the paraclinoid segment was found during the thrombectomy procedure. Two thrombectomy procedures failed to recanalize the acute internal carotid artery occlusion without removing any clot. Angiography performed during a Trevo stent retriever deployment in the first pass showed obscure contrast defects in the stent strut with temporary flow restoration. In the next pass, the appearance of the contrast defects changed and a parallel linear contrast appeared on the outside of the vessel wall. These angiographic findings were identified as mural hematoma and dissection flap, indicating dissection of the paraclinoid as the cause of the occlusion. During antiplatelet loading and preparation of a dedicated intracranial stent, the Trevo stent retriever was left deployed again at the occlusion site to maintain the blood flow. After permanent stenting with an Enterprise stent, angiography revealed complete recanalization. The patient recovered fully after the procedure. In the present case, stent retriever deployment revealed the hallmarks of dissection on angiography, such as mural hematoma, dissection flap, and temporal morphological changes, by restoring the blood flow temporarily. Such angiographic findings can provide useful information on the occlusion characteristics and real-time feedback for optimal treatment strategy.

Crossing double stent retriever technique for refractory terminal internal carotid artery occlusion.

Mechanical thrombectomy is highly effective for the recovery of acute ischemic stroke with large vessel occlusion. However, refractory occlusions are still encountered despite the use of currently available devices. In this article, we present a case of refractory terminal internal carotid artery occlusion treated with the "crossing double stent retriever technique." Two thrombectomy procedures with the combined technique using a stent retriever and aspiration catheter failed to recanalize the terminal internal carotid artery occlusion that involved the dominant anterior cerebral artery. We then applied the crossing double stent retriever technique as a rescue technique. Two microcatheters were advanced across the occlusion: one to the anterior cerebral artery and the other to the middle cerebral artery. First, a Trevo NXT 4 mm stent retriever was deployed from the anterior cerebral artery. Next, an additional Trevo NXT 4 mm stent retriever was deployed from the middle cerebral artery, and full immediate restoration of flow was achieved on angiography. Intraprocedural radiological images showed that the 2 microcatheters traversed different pathways, and the 2 stent retrievers completely covered the entire vessel with apparent in-stent clot sign. Both stent retrievers were then pulled back together, and a hard clot was retrieved. Subsequent angiography revealed complete recanalization. The crossing double stent retriever technique seems an effective rescue technique for treating refractory terminal internal carotid artery occlusion, especially with the anatomical feature of branching of the dominant anterior cerebral artery. This technique can facilitate the device-clot-vessel interaction by engaging the clot via 2 different device pathways.

[A Case of Moyamoya Disease with Postoperative Cerebral Hyperperfusion Syndrome Followed by Cerebral Infarction due to Watershed Shift].

The concept of "watershed shift"(WS)has been proposed as a cause of the ischemic complications following a superficial temporal artery-middle cerebral artery(STA-MCA)bypass operation performed for the management of moyamoya disease. Previous reports have observed that only 1.2-5.7% of the patients who underwent a bypass operation for the management of moyamoya disease developed cerebral infarction secondary to the WS phenomenon. To date, the WS phenomenon has not been objectively proven on imaging studies. We describe a 39-year-old woman who presented with right facial palsy and aphasia. Magnetic resonance imaging revealed cerebral infarction in the left frontal lobe secondary to moyamoya disease. Three days after undergoing the left STA-MCA bypass procedure, she showed deterioration in aphasia secondary to the occurrence of cerebral hyperperfusion syndrome(CHPS). Diffusion-weighted imaging(DWI)performed on postoperative day(POD)1 and 5 showed no area of high signal intensity. DWI performed on POD 8 showed an area of high signal intensity in the deep white matter of the left parietal lobe outside the range of the craniotomy. Postoperative fusion images of computed tomography angiography and DWI performed on POD 8 showed that the blood flow through the MCA from the bypass graft and that through the posterior cerebral artery crossed each other at the surface of the subcortical infarction. In the present case, the WS could be directly confirmed on imaging studies, and the cerebral infarction may have occurred secondary to WS concomitant with CHPS. Clinicians need to be aware of the WS phenomenon even after performing a direct bypass to treat adults with moyamoya disease.

Pituitary ischemic apoplexy in a young woman using oral contraceptives: a case report.

Estrogen is suggested to be one of the plausible risk factors for pituitary hemorrhagic apoplexy through pituitary hyperemia. We experienced a 33-year-old woman with pituitary ischemic apoplexy of a nonfunctional macroadenoma under oral contraceptive use. Our case indicates that hypercoagulable state, but not hyperemia, associated with estrogen may promote pituitary ischemic apoplexy.

[Is hyperdynamic therapy possible for elderly patients with vasospasm following subarachnoid hemorrhage?].

BACKGROUND: Recently we have an increased number of elderly patients with subarachnoid hemorrhage (SAH) to be treated. Elderly patients are expected to have a worse cardiac function than that of younger patients. A question arises whether management for elderly patients in the vasospasm period can be performed as safely as it is for younger patients. The aim of this study is to examine the cardiac function of the elderly patients (> or =75 y.o.) with SAH correlated with various complications in the vasospasm period. MATERIALS: We retrospectively analyzed consecutive 356 patients with SAH encountered in our institute since 2000 to 2006. Seventy-three patients (20.5% of all) are 75 or more than 75-year-old. Their mean age is 80.4 +/- 4.43 (16 male, 57 female). Cardiac function was examined by trans-thoracic echocardiography (CTE) in 40 patients (54.8%). RESULT: Average value of their ejection fraction (EF) and rates of perioperative complications were not so different from those of the younger patients. But among patients of > or =75 y.o., certain patients in whom EF was under 0.6 significantly have experienced cardiopulmonary complications and longer hospitalization. In a multiple logistic analyses, only EF is significantly related with cardiopulmonary complications (P = 0.013). CONCLUSIONS: Among elderly SAH patients > or =75 year of age, some have experienced more cardiopulmonary complications than younger patients and have needed longer hospitalization. For such patients hyperdynamic therapy must be carefully carried out. TTE is effective to predispose and help eliminate their cardiopulmonary complications in the pre- and postoperative period.

Concept of ideal closure line for clipping of middle cerebral artery aneurysms--technical note.

The concept of optimum closure line was applied to a series of 51 consecutive middle cerebral artery aneurysms (14 ruptured, 37 unruptured) in 41 patients, 16 men and 25 women aged 29-79 years (mean 59.1 years). Visual inspection through the operating microscope revealed 3 types of aneurysm based on the origin of the aneurysm: bifurcation type (n = 39), trunk type (n = 9), and combined type (n = 3). Clipping along the optimum closure line should restore the vascular structure to the original configuration. Combination clip techniques were useful to form a curved closure line. This technique requires adequate operative fields with dissection of the aneurysm and related arteries from the neighboring structures as far as possible. The closure line concept is helpful to decide how to apply clips for particular aneurysms to avoid risks of ischemic complication and future recurrence. Combination clip techniques are often necessary to match a curved closure line.

[Elderly patient with cerebellar malignant astrocytoma].

Malignant cerebellar astrocytoma is very rare and the prognosis is extremely poor. We report herein the case of an elderly patient with malignant cerebellar astrocytoma. This 80-year-old man initially presented with dizziness and ataxia of the right hand. Metastatic cerebellar tumor was diagnosed on first admission, based on a past history of colon cancer treated by surgery and magnetic resonance imaging (MRI) findings supporting the diagnosis of metastasis. The patient underwent gamma knife surgery (20 Gy) and was discharged. Follow-up after discharge was insufficient. Two years after gamma knife surgery, he returned to our hospital complaining of dizziness, headache, and right limb ataxia. MRI revealed a cystic mass in the right cerebellar hemisphere, and the lesion was removed by right suboccipital craniotomy. The tumor represented malignant astrocytoma. Optimal management of patients harboring sush difficult. to-treat tumors, including the role of gamma-knife radiosurgery, is discussed.

Snoring associated with Ondine's curse in a patient with brainstem glioma.

UNLABELLED: Ondine's curse is an uncommon type of sleep apnea syndrome characterized by failure of automatic respiration. We present an adult patient with brainstem glioma who presented with snoring and Ondine's curse as the only symptoms. CASE REPORT: A 52-year-old female was brought to the hospital by a fellow resident due to exceptionally loud snoring. During the hospitalization, Ondine's curse was diagnosed after monitoring using Apnomonitor 5 (Chest Co., Tokyo), a cheap, non-invasive respiratory monitoring procedure. MRI and MR spectroscopy revealed a brainstem glioma. After radiation therapy, clinical response was documented using repeat apnomonitoring. CONCLUSION: Exceptionally loud snoring in non-obese adult patients with sleep apnea may be an early feature of a brainstem space-occupying lesion. Overnight sleep respiratory evaluation and neuroimaging should be considered in such instances.

Acquired lumbar epidermoid cyst in an adult.

A 61-year-old female complained of low back pain, and had been treated by spinal anesthetic injection more than 70 times over 14 years. Magnetic resonance (MR) imaging, performed at the age of 47 years, revealed no abnormal lesion. However, she developed irritable hypesthetic pain in the left leg at 61 years of age. MR imaging revealed a round mass appearing isointense on the T1-weighted and slightly hyperintense on the T2-weighted images. Laminectomy revealed an epidermoid cyst, which was removed. This case clearly demonstrates that adults can acquire epidermoid tumor which very probably has an iatrogenic origin. The incidence of epidermoid tumor is low, but we should be aware of the potential adverse complications such as formation of epidermoid tumors after lumbar puncture.