Asymptomatic subarachnoid hemorrhage following carotid endarterectomy: illustrative case.

BACKGROUND: Carotid endarterectomy (CEA) and carotid artery stenting are common surgical interventions for internal carotid artery stenosis. Cerebral hyperperfusion syndrome (CHS) is a well-known complication of both procedures that can lead to intracranial hemorrhage and worsen clinical outcomes. Here, the authors report a rare case of non-aneurysmal subarachnoid hemorrhage (SAH) following CEA and review the relevant literature. OBSERVATIONS: A 70-year-old woman with hypertension and diabetes presented with progressive visual loss in the right eye and was diagnosed with ocular ischemic syndrome. Imaging revealed severe right cervical carotid artery stenosis. CEA was performed with no complications. Postoperatively, the patient's blood pressure was tightly controlled, with no evidence of CHS. However, an asymptomatic SAH was detected on postoperative day 7. Careful observation and blood pressure control were maintained. Since follow-up magnetic resonance imaging (MRI) showed no enlarging of the SAH and the patient was asymptomatic, she was discharged on postoperative day 15 with a modified Rankin scale score of 0. LESSONS: This case highlights the potential occurrence of non-aneurysmal SAH as a rare complication of CEA, even in asymptomatic patients. Repeated postoperative MRI is necessary to detect such complications. It is crucial to carefully control blood pressure after CEA regardless of symptoms.

Location of hemorrhage with nontraumatic acute subdural hematoma due to ruptured microaneurysm.

BACKGROUND: Nontraumatic acute subdural hematoma (ASDH) may be caused by rupture of a microaneurysm of a cortical artery. In some cases, microaneurysms may have been caused by earlier trauma. Although it is difficult to detect microaneurysms on contrast-enhanced computed tomography (CT) angiography or digital subtraction angiography, it may be suspected based on the plain CT scan results and the clinical course. CASE DESCRIPTION: We experienced three cases presumed to be ASDH due to rupture of a microaneurysm. Plain CT scan showed that the midline shift was smaller than the hematoma thickness, and we judged from the clinical course that there was no trauma immediately before the onset. All three patients had decreased consciousness after arrival and underwent craniotomy for hematoma removal. The source of hemorrhage was in the distal part of the cortical artery, and a microaneurysm was found. In one case, histopathological examination was performed, and traumatic pseudoaneurysm was diagnosed. The postoperative course was good in all three cases. CONCLUSION: If nontraumatic ASDH is suspected, the source of hemorrhage may be located more distally to the middle cerebral artery than in traumatic ASDH; hence, extensive craniotomy is required to search for the location of hemorrhage.

Development of Valve Reversal After Lumboperitoneal Shunt Construction.

OBJECTIVE: The current study aimed to assess the risk factors and preventive measures for valve inversion after lumboperitoneal shunt (LPS) construction. METHODS: The medical records of patients who were admitted to Mito Brain Heart Center from July 2015 to October 2018 were retrospectively analyzed. Next, clinical and neuroimaging data were collected from electronic medical charts and operative notes. The cause of valve reversal was investigated. In addition, a simulated shunt device was established and the efficacy of countermeasures was evaluated. RESULTS: The mean age of the participants was 69.3 (range: 46-88) years, and there were 15 men and 22 women. In total, 20 and 17 patients presented with secondary and idiopathic normal pressure hydrocephalus, respectively. Further, 8 patients had valve reversal. CONCLUSIONS: The distance between the valve and spinous process was found to be significantly correlated with valve reversal. However, the condition can be prevented by fixing the tube at the nuchal ligament.

Emergency embolectomy for acute middle cerebral artery occlusion with chronic common carotid artery occlusion.

Occurrence of acute middle cerebral artery occlusion with common carotid artery occlusion is rare, and its treatment may be complicated. If the approach route cannot be secured because of carotid artery occlusion, endovascular embolectomy may not be indicated. The best treatment approach for such cases remains controversial. A woman in her 70s was transferred to our hospital in ambulance following a sudden onset of dysarthria and left hemiparesis. Magnetic resonance imaging revealed an ischemic lesion in the right basal ganglia and occlusion of the right common carotid and intracranial middle cerebral arteries. Emergency embolectomy was performed for acute middle cerebral artery occlusion. Postoperative magnetic resonance imaging revealed complete recovery of the right middle cerebral artery blood flow. Emergency embolectomy can effectively treat acute middle cerebral artery occlusion with common carotid artery occlusion.

Preoperative risk assessment for predicting the opening of mastoid air cells in lateral suboccipital craniotomy for microvascular decompression.

OBJECTIVE: Opening of mastoid air cells (MACs), a complication of lateral suboccipital craniotomy for microvascular decompression (MVD), might cause cerebrospinal fluid (CSF) leakage and meningitis. Only a few studies have investigated the association of degree of MAC development and actual opening of MACs. The present study focused on preoperative risk assessment for predicting the opening of MACs. PATIENTS AND METHODS: The study included 204 consecutive patients who underwent MVD at our hospital between January 2014 and December 2018. We retrospectively collected clinical and neuroimaging data from electronic medical charts and discharge summaries. MACs were classified into four types according to neuroimaging data. Postoperative computed tomography (CT) was used to assess patients with and without CSF leakage into MACs. RESULTS: No CSF leakage was observed into types 1 and 2 MACs, but it was noted in 14 of 46 patients (30 %) with type 3 and 44 of 58 patients (76 %) with type 4 MACs. Opening of MACs during surgery could not be recognized in 33 (57 %). CSF rhinorrhea was noted in 1 of the 58 patients with CSF leakage into MACs and meningitis was not noted. CONCLUSION: Patients with types 3 and 4 MACs have a high risk of CSF leakage. Complete prevention of mild symptoms, such as ear obstruction, is challenging even if opened MACs are sealed, but serious complications, such as CSF rhinorrhea and meningitis, can be avoided. For cases in which preoperative CT reveals a high risk of opening of MACs, preventive closure should be performed.

Indications and Timings of Re-operation for Residual or Recurrent Hemifacial Spasm after Microvascular Decompression: Personal Experience and Literature Review.

We reviewed reports about the postoperative course of hemifacial spasm (HFS) after microvascular decompression (MVD), including in our own patients, and investigated treatment for delayed resolution or recurrence of HFS. Symptoms of HFS disappear after surgery in many patients, but spasm persists postoperatively in about 10-40%. Residual spasm also gradually decreases, with rates of 1-13% at 1 year postoperatively. However, because delayed resolution is uncommon after 1 year postoperatively, the following is advised: (1) In patients with residual spasms after 1 year postoperatively (incomplete cure) or who again experience spasm ≥ 1 year postoperatively (recurrence), re-operation is recommended if the spasms are worse than before MVD. (2) When re-operation is considered, preoperative magnetic resonance imaging (MRI) findings and intraoperative videos should be reviewed to ensure that no compression due to a small artery or vein was missed, and to confirm that adhesions with the prosthesis are not causing compression. If any suspicious findings are identified, the cause must be eliminated. Moreover, because of the risk of nerve injury, decompression of the distal portion of the facial nerve should be performed only in patients in whom distal compression is strongly suspected to be the cause of symptoms. (3) Cure rates after re-operation are high, but complications such as hearing impairment and facial weakness have been reported in 10-20% of cases, so surgery must be performed with great care.

[A case of ruptured aneurysm of the middle cerebral artery associated with dural arteriovenous fistula in the anterior cranial fossa].

A 66-year-old man suffered from subarachnoid hemorrhage due to the rupture of a right middle cerebral artery aneurysm that was detected by 3D-CTA. He underwent an emergent clipping operation. Incidentally, postoperative DSA demonstrated dural arteriovenous fistula in the left anterior cranial fossa, which was fed by the left anterior ethmoidal artery and drained into the superior sagittal sinus via the cortical vein of the left frontal lobe. We performed electrocoagulation and division of the fistula at the second surgery. Subsequently, he underwent a ventriculo-peritoneal shunt and was discharged without any neurological deficits. We reviewed reported cases of rare association of ruptured cerebral aneurysm and dural arteriovenous fistula in the left anterior cranial fossa.

Context-dependent cortical activation in response to financial reward and penalty: an event-related fMRI study.

An event-related fMRI technique was used to assess neural responses to financial reward and penalty during a simple gambling task. We attempted to determine whether brain activities are dependent on the unique context of an event sequence. Thirty-six healthy volunteers participated in the study. The task was to guess the color of the suit of a card on each trial and to respond by pressing a button. Every correct response ("win") and incorrect response ("loss") was associated with financial reward and penalty, respectively. The magnitude of reward or penalty in each trial did not change; however, the subjects' self-reported emotional arousal was significantly higher for the events of "the fourth win of four wins in a row" and "the fourth loss of four losses in a row." We also found that the bilateral anterior cingulate and medial prefrontal cortices were specifically activated when the subjects experienced "the fourth win of four wins in a row" and "the fourth loss of four losses in a row." When the subjects experienced "a win following four losses in a row" or "a loss following four wins in a row," the right dorsolateral prefrontal cortex was specifically activated. Our data indicate that there exist brain activities associated with the event-sequence context in which abstract reward or penalty is received. These context-dependent activities appear to be crucial for adapting oneself to new circumstances and may account for clinical symptoms of various mental illnesses in which dysfunction of these regions has been reported.

Nonenzymatic derived lipid peroxide, 8-iso-PGF2 alpha, participates in the pathogenesis of delayed cerebral vasospasm in a canine SAH model.

We studied whether 8-iso-PGF2alpha, nonenzymatic arachidonyl peroxide, participated in the pathogenesis of delayed vasospasm using a canine subarachnoid hemorrhage (SAH) model. Fourteen adult mongrel dogs were divided into two groups, two-hemorrhage SAH group (n = 8) and control group (n = 6). The contents of 8-iso-PGF2alpha in CSF, the basilar artery segment, and subarachnoid clot were measured by enzyme immunoassay kit. The CSF 8-iso-PGF2alpha content on Day 7 in the SAH group was 67.9+/-29.9 pg ml(-1) (n = 8), which was significantly higher than 27.1+/-13.8 (n = 8) on Day 0 in the SAH group, and 33.2+/-14.4 pg ml(-1) (n = 5) on Day 7 in the control group. The 8-iso-PGF2alpha content in the basilar artery segment with spasm on Day 7 in the SAH group was 13.5+/-1.9 pg mg(-1) wet weight (n = 8), significantly higher than 8.7+/-1.9 (n = 6) in the control group. The 8-iso-PGF2alpha content in subarachnoid clot was 1.7+/-1.4 ng g(-1) wet weight (n = 8). Significant elevation of the 8-iso-PGF2alpha contents in the CSF and the basilar artery segment occurred on Day 7 in the SAH group. The subarachnoid clot enclosed the basilar artery on Day 7, contained a considerable amount of 8-iso-PGF2alpha. These results suggested that 8-iso-PGF2alpha could play a crucial role in the pathogenesis of the delayed cerebral vasospasm.