A preliminary study of relationship among the degree of internal carotid artery stenosis, wall shear stress on MR angiography and 18F-FDG uptake on PET/CT.

BACKGROUND: This preliminary study was undertaken to evaluate relationship among the degree of internal carotid artery (ICA) stenosis, wall shear stress (WSS) by computational fluid dynamics (CFD) on magnetic resonance angiography (MRA) and 18F-FDG uptake of ICA on PET/CT. METHODS: A total of 40 carotid arteries in 20 patients with carotid atherosclerotic disease were examined with MRA and 18F-FDG PET/CT. Atherosclerotic risk factors were assessed in all patients. Degree of ICA stenosis was calculated according to NASCET method. CFD analysis was performed and maximum WSS (WSSmax) was measured. 18F-FDG uptake in ICA was quantified using maximum target-to-blood pool ratio (TBRmax). RESULTS: Atherosclerotic risk factors did not affect imaging findings. There were significant correlations between WSSmax and degree of ICA stenosis (ρ = .81, P < .001), WSSmax and TBRmax (ρ = .64, P < .001), and TBRmax and degree of ICA stenosis (ρ = .50, P = .001). CONCLUSIONS: These preliminary results indicate that there may be significant correlations among the degree of ICA stenosis, WSSmax and TBRmax in patients with carotid artery stenosis.

Histidine-rich Glycoprotein Could Be an Early Predictor of Vasospasm after Aneurysmal Subarachnoid Hemorrhage.

Cerebral vasospasm (CVS) is a major contributor to the high morbidity and mortality of aneurysmal subarachnoid hemorrhage (aSAH) patients. We measured histidine-rich glycoprotein (HRG), a new biomarker of aSAH, in cerebrospinal fluid (CSF) to investigate whether HRG might be an early predictor of CVS. A total of seven controls and 14 aSAH patients (8 males, 6 females aged 53.4±15.4 years) were enrolled, and serial CSF and serum samples were taken. We allocated these samples to three phases (T1-T3) and measured HRG, interleukin (IL)-6, fibrinopeptide A (FpA), and 8-hydroxy-2'-deoxyguanosine (8OHdG) in the CSF, and the HRG in serum. We also examined the release of HRG in rat blood incubated in artificial CSF. In contrast to the other biomarkers examined, the change in the CSF HRG concentration was significantly different between the nonspasm and spasm groups (p<0.01). The rat blood/CSF model revealed a time course similar to that of the human CSF samples in the non-spasm group. HRG thus appears to have the potential to become an early predictor of CVS. In addition, the interaction of HRG with IL-6, FpA, and 8OHdG may form the pathology of CVS.

Blood Glucose Variability: A Strong Independent Predictor of Neurological Outcomes in Aneurysmal Subarachnoid Hemorrhage.

PURPOSE: In patients with aneurysmal subarachnoid hemorrhage (SAH), increased glucose variability (GV) is associated with increased mortality and cerebral infarction; however, there are no reports demonstrating an association between GV and neurological outcome. This study investigated whether GV had an independent effect on neurological outcomes in patients with SAH in the intensive care unit. MATERIALS AND METHODS: Consecutive adult patients hospitalized with SAH between January 1, 2009, and May 31, 2015 (N = 122) were retrospectively reviewed. Univariate/multivariate analyses were performed to identify independent predictors of poor neurological outcome. Patients were divided according to the mean glucose level (80-139 vs 140-200 mg/dL) and further subdivided using quartiles (Q) of the standard deviation (SD, representing variability) of the glucose level (Q1, Q2 + 3, and Q4). RESULTS: Unfavorable neurological outcomes occurred in 44.2% of the patients. On multiple regression analysis, age, Hunt and Kosnik grade, SD of glucose (odds ratio [OR], 1.09; 95% confidence interval [CI], 1.02-1.17; P < .01), and minimum blood glucose level (OR, 0.95; 95% CI, 0.91-0.99; P < .01) were significantly associated with unfavorable neurological outcomes. Both groups (mean glucose levels: 80-139 and 140-200 mg/dL groups) had increasing unfavorable neurological outcomes with increasing SD of glucose (Q1, 15.0%; Q2 + 3, 40.0%; Q4, 52.4% and Q1, 44.4%; Q2 + 3, 50%; Q4, 88.9% in the 80-139 and 140-200 mg/dL groups, respectively). Patients with minimum glucose of <90 mg/dL comprised >50% of unfavorable neurological outcome. CONCLUSION: Increased GV was an independent predictor of unfavorable neurological outcomes in patients with SAH.

Cerebral blood flow and oxygen metabolism measurements using positron emission tomography on the first day after carotid artery stenting.

BACKGROUND: The aim of the present study is the characterization of hemodynamics to predict hyperperfusion syndrome (HPS) after carotid artery stenting (CAS) with positron emission tomography (PET) obtained before and on the first day after the treatment. METHODS: Cerebral perfusion and oxygen metabolism were evaluated by (15)O-gas PET in 18 patients with symptomatic internal carotid artery (ICA) stenosis before and on the first day after CAS. Regional cerebral blood flow (CBF), oxygen extraction fraction (OEF), cerebral metabolic rate of oxygen (CMRO2), and cerebral blood volume (CBV) were measured in the ipsilateral and contralateral middle cerebral artery territories and compared between before and after CAS. RESULTS: CBF increased in 16 of 18 patients on the first day after CAS and postoperative CBF was significantly higher than preoperative CBF bilaterally. OEF decreased in 15 of 18 patients on the first day after CAS and postoperative OEF was significantly lower than preoperative OEF in the ipsilateral hemisphere. CMRO2 and CBV did not change significantly. None of the patients showed HPS after CAS. All patients who had preoperative OEF of 53% or more (misery perfusion) in the ipsilateral hemisphere showed 50% or more increase in CBF postoperatively. The preoperative OEF value significantly correlated with the rate of postoperative increase in CBF bilaterally. CONCLUSIONS: CAS increases cerebral perfusion and improves hemodynamic compromise in patients with symptomatic ICA stenosis. Although we could not clarify the usefulness of PET before and on the first day after CAS in predicting HPS, a high preoperative OEF is related to postoperative marked CBF increase and might be used as a predictor of HPS. Patients with greater hemodynamic compromise with a high preoperative OEF should be managed carefully to prevent HPS, but they have a greater chance of CBF increase after CAS.

[Intrapituitary adenoma metastasis from lung cancer with progressive cranial nerve palsies: a case report and literature review].

We report a rare case of metastasis to a preexisting pituitary adenoma. An 80-year-old man with a history of pituitary adenoma and lung cancer presented with recent onset of bilateral visual impairment, oculomotor nerve palsies, and severe headache. A CT scan revealed a pituitary tumor expanding into the suprasellar region and infiltrating the bilateral cavernous sinuses. We performed transsphenoidal surgery and diagnosed the tumor as lung cancer metastasis to the pituitary adenoma. After the surgery, visual impairment and severe headache were resolved, and the patient underwent radiation therapy for the residual tumor. To the best of our knowledge, 20 cases of metastases to pituitary adenomas have been reported in the literature. Clinical features of metastasis to a pituitary adenoma are different from those of metastasis to normal pituitary gland. In the case of a pituitary lesion with acute aggravation, one should be aware of the possibility of metastasis to preexisting pituitary adenomas.

Revealing subependymal giant cell astrocytoma with multimodal positron emission tomography: illustrative cases.

BACKGROUND: There is limited literature on the use of positron emission tomography (PET) for benign tumors originating in the brain ventricles, and the use of multiple tracers for subependymal giant cell astrocytoma (SEGA) has not been reported. The authors compared the PET findings in two SEGA cases with past reports and literature, exploring the distinctive characteristics of SEGA on PET. OBSERVATIONS: In a 21-year-old female with SEGA, the authors utilized 18F-fluorodeoxyglucose (18F-FDG), 11C-methionine (11C-MET), 18F-fluorothymidine (18F-FLT), 18F-fluoromisonidazole, and 18F-THK5351 tracers. Additionally, in a 6-year-old girl, the authors performed 11C-MET PET. LESSONS: The results indicated the accumulation of all tracers except 18F-FDG, with particularly intense accumulation noted with 18F-FLT. In particular, 18F-FLT demonstrated accumulation comparable to that observed in malignant tumors. This study suggests that multiple PET tracers can provide valuable insights into the characterization of SEGA, with 18F-FLT showing particular promise as a distinctive marker of blood-brain barrier disruption. Further research in larger cohorts may enhance our understanding of metabolic patterns in SEGA and aid in its diagnosis and treatment. https://thejns.org/doi/10.3171/CASE24111.

Detection of brain amyloid ß deposition in patients with neuropsychological impairment after traumatic brain injury: PET evaluation using Pittsburgh Compound-B.

OBJECTIVE: Traumatic brain injury (TBI) is an epigenetic risk factor for Alzheimer's disease (AD) and amyloid ß (Aß) deposition is observed histopathologically in the traumatized brain. This study was conducted to detect cerebral Aß deposition using amyloid positron emission tomography (PET) in patients with neuropsychological impairment after TBI. METHODS: Twelve patients with post-traumatic neuropsychological impairment (11 men and one woman, age range = 21-78 years) were examined using Pittsburgh Compound B ((11)C-PIB) PET at the chronic stage after TBI (range = 5-129 months). RESULTS: (11)C-PIB was positive in three patients and negative in the other nine patients. There was no correlation between (11)C-PIB deposition and the severity of injury; initial CT findings; elapsed time from the injury; and neuropsychological test scores. CONCLUSIONS: The absence of Aß deposition in many patients with chronic neuropsychological impairment after TBI does not support the premise that Aß pathology progresses over time in the traumatized brain. Early and sequential (11)C-PIB PET examination may clarify the time course of Aß deposition in the traumatized brain and the relationship between traumatic brain insult and subsequent neuropsychological impairment.

A novel catheter interaction simulating method for virtual reality interventional training systems.

Endovascular robotic systems have been applied in robot-assisted interventional surgery to improve surgical safety and reduce radiation to surgeons. However, this surgery requires surgeons to be highly skilled at operating vascular interventional surgical robot. Virtual reality (VR) interventional training systems for robot-assisted interventional surgical training have many advantages over traditional training methods. For virtual interventional radiology, simulation of the behaviors of surgical tools (here mainly refers to catheter and guidewire) is a challenging work. In this paper, we developed a novel virtual reality interventional training system. This system is an extension of the endovascular robotic system. Because the master side of this system can be used for both the endovascular robotic system and the VR interventional training system, the proposed system improves training and reduces the cost of education. Moreover, we proposed a novel method to solve catheterization modeling during the interventional simulation. Our method discretizes the catheter by the collision points. The catheter between two adjacent collision points is treated as thin torsion-free elastic rods. The deformation of the rod is mainly affected by the force applied at the collision points. Meanwhile, the virtual contact force is determined by the collision points. This simplification makes the model more stable and reduces the computational complexity, and the behavior of the surgical tools can be approximated. Therefore, we realized the catheter interaction simulation and virtual force feedback for the proposed VR interventional training system. The performance of our method is experimentally validated.

Current Treatment Results of Intracranial Carotid Artery Dissection Causing Cerebral Ischemia: A Japanese Nationwide Survey.

Intracranial carotid artery dissection causing cerebral ischemia is a rare but important cause of cerebral infarction in children and adolescents. Although endovascular therapy has been reported to be effective, questions regarding the indications for intervention are yet to be addressed. Therefore, this study aimed to evaluate factors related to clinical outcomes through a nationwide survey. Overall, 35 neurosurgical centers reported patients within 2 weeks after ischemic onset due to intracranial carotid artery dissection causing cerebral ischemia treated between January 2015 and December 2020. Data on clinical and radiological findings were statistically analyzed. Twenty-eight patients met the inclusion criteria. The median age was 36 years (range, 7-59 years), without sex differences. Headache at onset was documented in 60.7% of the patients. Dissection findings were categorized into stenosis (71.4%) or occlusion (28.6%). Initial treatments, including various antithrombotic agent combinations in 23 (82.1%) patients, effectively improved or prevented aggravation in half of the patients. The patients with stenotic dissection were significantly more likely to experience aggravation during the initial treatment than did those with occlusive dissection (P = 0.03). In addition, the patients with moderate to severe neurological deficits on admission had poorer outcomes at discharge more frequently than did those with mild neurological deficits on admission. Eight patients undergoing endovascular therapy had no procedural complications or further aggravation after intervention. In conclusion, patients with intracranial carotid dissection causing cerebral ischemia who had a stenotic dissection were at risk of further aggravation, and endovascular therapy effectively improved or prevented aggravation.

[Case of metastatic malignant melanoma detected by multifocal cerebral hemorrhage].

We encountered a case of intracranial metastatic malignant melanoma which caused repeated multiple hemorrhage. Intracranial metastatic malignant melanoma showed high intensity in the magnetic resonance imaging's T1 weighted image, low intensity in T2 weighted image and very low intensity in T2* weighted image. Positron emission tomographic scans are useful for systemic evaluation of active malignancies. The present case underwent tumor removal following re-bleeding. The patient died of repeated hemorrhage one month after the operation. Intracranial metastatic malignant melanoma has a strong propensity to cause intracerebral hemorrhage leading to clinical deterioration. We think that the development of a therapeutic strategy for the treatment of intracranial metastatic malignant melanoma, including its risk management of intracerebral hemorrhage would be great importance.

An Endovascular Catheterization Robotic System Using Collaborative Operation with Magnetically Controlled Haptic Force Feedback.

Robot-assisted technology is often used to perform endovascular catheterization surgeries, which generally depend on the flexible operability and the accurate force feedback of a robotic system. In this paper, an endovascular catheterization robotic system (ECRS) was developed to improve collaborative operation and haptic force feedback. A couple of operating handles were designed to maximize the use of the natural operations of surgeons on the master side, which is a flexible and ergonomic device. A magnetically controlled haptic force feedback structure is proposed based on hydrogel and solid magnetorheological (MR) fluid to offer a sense of haptic feedback to operators; this has potential influence on the field of force feedback. In addition, a unique tremor-reduction structure is introduced to enhance operating safety. Tracking performance experiments and in vitro experiments were conducted to evaluate the performance of the developed ECRS. According to these experimental results, the average translation-tracking error is 0.94 mm, and the average error of rotation is 0.89 degrees. Moreover, in vitro experiments demonstrated that haptic feedback has the advantage of reducing workload and shortening surgery completion time. The developed ECRS also has the benefits of inspiring other researchers to study collaborative robots and magnetically controlled feedback.

Endovascular Treatment for Posterior Communicating Artery Aneurysms with Oculomotor Nerve Palsy.

Objective: Coil embolization for the treatment of internal carotid artery-posterior communicating artery aneurysms (PComAAn) associated with oculomotor nerve palsy (ONP) remains controversial in terms of the therapeutic effect to improve ONP. Patients with PComAAn treated in our hospital were retrospectively analyzed to evaluate the effectiveness of coil embolization on ONP. Methods: Twenty-three patients who had coil embolization for PComAAn with ONP were included in the analysis. In the evaluation of postoperative outcome of ONP, complete resolution of all symptoms was considered as a total recovery. ONP with a few residual symptoms that are stable and not disabling was considered as a subtotal recovery and that with only a slight improvement as a partial recovery. Results: Preoperative ONP was complete palsy in 14 and partial palsy in nine cases. The mean maximum diameter of the aneurysms was 9.1 ± 3.5 mm (3-17 mm), and the mean time from the onset to treatment was 46.3 ± 98.4 days (0-300 days). The embolization state immediately after the procedure was complete occlusion in seven, neck remnant in eight, and body filling (BF) in eight cases. Total recovery was observed in nine, subtotal recovery in 11, and partial recovery in three cases. The mean time to any improvement in ONP was 6.0 ± 6.0 months (0.5-25 months). Comparing 20 cases with total plus subtotal recovery and three cases with partial recovery, five (25.0%) and three (100%) cases showed BF immediately after the procedure, respectively, which was statistically significant (P = 0.015). Conclusion: The analysis indicated that coil embolization for the treatment of PComAAn with ONP resulted in satisfactory recovery of ONP in 87% of the cases and the outcome of aneurysm embolization was related to improvement in ONP.

Case Series of Endovascular Therapy for Blood Blister-Like Aneurysm in Acute Phase.

Objective: Blood blister-like aneurysms (BBAs) of the internal carotid artery are highly challenging to treat due to their variable morphology and tendency for rupture and regrowth. Here, we report a single-institution experience of endovascular therapy (EVT) for BBA treatment. Methods: We retrospectively reviewed patients with ruptured BBA from 2006 to 2019. All patients in whom BBA was treated with EVT were included. Patients' aneurysmal characteristics, progression status, aneurysm occlusion on follow-up angiography, and modified Rankin Scale (mRS) score were recorded. Results: A total of 11 patients (5 women and 6 men) with the mean age of 46 ± 10 years were included in this study. As initial treatment, 9 patients were treated with stent-assisted coiling (SAC). Immediate angiographic results showed that 2 cases were body filling, 4 were neck remnant, and 3 were complete obliteration. Perioperative ischemic complications were not observed. On postoperative day 1, 2 patients suffered from rerupture, and their prognoses were poor. Retreatments were performed in 5 patients. Parent artery occlusion (PAO) was performed in 6 patients including 2 initial treatments and 4 retreatments. Symptomatic infarction developed in 2 patients. In 3 patients, bypass in combination with PAO was performed. Clinical data revealed discharge mRS scores of 0-2 and 3-6 in 4 and 7 patients, respectively. Conclusion: SAC is effective for the management of BBA. Careful follow-up and response are necessary after treatment with SAC.

A Mirror Bilateral Neuro-Rehabilitation Robot System with the sEMG-Based Real-Time Patient Active Participant Assessment.

In this paper, a novel mirror visual feedback-based (MVF) bilateral neurorehabilitation system with surface electromyography (sEMG)-based patient active force assessment was proposed for upper limb motor recovery and improvement of limb inter-coordination. A mirror visual feedback-based human-robot interface was designed to facilitate the bilateral isometric force output training task. To achieve patient active participant assessment, an sEMG signals-based elbow joint isometric force estimation method was implemented into the proposed system for real-time affected side force assessment and participation evaluation. To assist the affected side limb efficiently and precisely, a mirror bilateral control framework was presented for bilateral limb coordination. Preliminary experiments were conducted to evaluate the estimation accuracy of force estimation method and force tracking accuracy of system performance. The experimental results show the proposed force estimation method can efficiently calculate the elbow joint force in real-time, and the affected side limb of patients can be assisted to track output force of the non-paretic side limb for better limb coordination by the proposed bilateral rehabilitation system.

Clinicopathologic Factors Associated with Tumor Necrosis after Preoperative Embolization of Meningiomas.

Objective: Preoperative embolization of meningiomas induces necrosis prior to surgery and facilitates resection. Lack of contrast enhancement on postembolization MRI correlates with pathological findings of necrosis and can be used to assess embolization efficacy. This study aimed to examine clinicopathologic factors associated with tumor necrosis after embolization. Methods: A total of 119 patients with intracranial meningioma who underwent 145 surgical resections between 2010 and 2019 at our institute were reviewed. Inclusion criteria for the study were preoperative embolization with trisacryl gelatin microspheres (Embosphere) or absorbable gelatine sponge (Gelfoam). Postembolization Gd-enhanced T1-weighted and angiographic imaging, and histopathologic examination results were reviewed to evaluate the effectiveness of embolization. Results: In all, 66 patients satisfied the inclusion criteria. In total, 36 patients were embolized with Embosphere and 30 patients were embolized with Gelfoam. Patients embolized with Embosphere had a significantly higher necrosis rate (NR) than patients with Gelfoam (21% vs. 7.1%, P <0.01). The 36 Embosphere patients were analyzed regarding clinicopathologic factors associated with NR. Tumors in 12 patients were located in the parasagittal/falx region; these patients had a significantly lower NR compared with tumors in other locations (10.6% vs. 26.2%, P = 0.016). In all, 13 patients had feeders arising from only the middle meningeal artery (MMA), which was associated with a significantly higher NR (29.3% vs. 14.4%, P = 0.015). In total, 11 patients had meningeal feeders arising from internal carotid artery (ICA), which was associated with a significantly lower NR (9.0% vs. 26.3%, P <0.01). Conclusion: This study showed embolization agent, tumor location, and blood supply were important factors predicting necrosis after preoperative embolization.

A case of bleeding from maxillary carcinoma embolized from the maxillary and ophthalmic arteries.

BACKGROUND: The majority of maxillary sinus cancers are advanced at initial detection due to anatomical limitations and lack of early symptoms. In patients with orbital invasion, the feeding arteries of the tumor are often associated with the ophthalmic artery in addition to the maxillary artery. We describe a case of tumor bleeding in a patient with recurrent maxillary carcinoma that was treated with embolization from the maxillary and ophthalmic arteries. CASE PRESENTATION: A 70-year-old man was treated for left maxillary carcinoma from the maxillary artery with 6 cycles of selective intra-arterial cisplatin infusion with concomitant radiation therapy. He subsequently had epistaxis and underwent arterial embolization for hemostasis. He had almost no sight by this time. Angiography of the left external carotid artery and internal carotid artery revealed blood supply from the maxillary and ophthalmic arteries. Regarding the maxillary artery, coil embolization was performed after embolization with 300-500 µm Embosphere. On the other hand, for the ophthalmic artery, the 3rd portion, supratrochlear artery and dorsal nasal artery, were selected and embolized with coils. Final angiography revealed disappearance of tumor staining and a residual choroidoretinal blush. There was no bleeding that needed treatment up to 2 months after embolization. CONCLUSIONS: In embolization of the ophthalmic artery, it is necessary to embolize the second and subsequent parts because the arteries associated with visual function branch off from the first part. Even in patients whose visual acuity has been almost lost, like in this case, there is a risk of eye pain from embolization at the proximal end, and distal embolization is necessary.

Association between carotid 18F-NaF and 18F-FDG uptake on PET/CT with ischemic vascular brain disease on MRI in patients with carotid artery disease.

OBJECTIVE: Atherosclerosis is a dynamic and complex process characterized by the formation and progression of plaque mediated by various pathophysiologic steps including inflammation and calcification. The present study aimed to evaluate the association between carotid 18F-sodium fluoride (NaF) and 18F-fluorodeoxyglucose (FDG) uptake with the severity of ischemic vascular brain disease on MRI in patients with carotid artery disease. METHODS: A total of 28 patients who were scheduled to undergo clinically indicated carotid endarterectomy or stenting for carotid artery disease were examined with 18F-NaF and 18F-FDG PET/CT and brain MRI. The PET/CT images were evaluated by qualitative and semiquantitative analyses. The maximum standardized uptake value (SUV) for the plaque and the average of mean SUV within the lumen of both internal jugular veins was calculated, and the target-to-blood pool ratio (TBR) was determined. The ischemic vascular brain disease on MRI was graded separately in the bilateral hemisphere as 0, 1, 2, and 3, with 0 being absent and 3 being the most severe. RESULTS: In two patients, only a unilateral carotid artery was analyzed because of previous indwelling stent. 18F-NaF focal uptake was observed in 50 carotid arteries. 18F-FDG focal uptake was observed in 47 carotid arteries. The mean (± SD) 18F-NaF TBR (2.93 ± 0.89) was significantly higher than the mean (± SD) 18F-FDG TBR (2.41 ± 0.84) (p < 0.001). The mean (± SD) values of 18F-NaF TBR were 2.63 ± 0.76 in grade 1, 2.90 ± 0.91 in grade 2, and 3.81 ± 0.60 in grade 3. Significant differences in 18F-NaF TBR were observed between grades 1 and 3 (p < 0.001) and grades 2 and 3 (p = 0.02). The mean (± SD) values of 18F-FDG TBR were 2.35 ± 0.77 in grade 1, 2.23 ± 0.48 in grade 2, and 2.87 ± 1.32 in grade 3. No significant differences in 18F-FDG TBR were noted between any of the ischemic vascular brain disease grades. CONCLUSIONS: These preliminary results suggest that carotid 18F-NaF uptake in patients with carotid artery disease may be associated with the severity of the ischemic vascular brain disease observed on MRI.

A Rare Case of Postoperative Symptomatic Cyst Formation After Resection of a Large Convexity Meningioma.

BACKGROUND: Symptomatic cyst formation after brain tumor resection is a rare complication of the early postoperative phase. We describe a complicated case of postoperative symptomatic cyst formation after gross total removal of a convexity meningioma. CASE DESCRIPTION: A 59-year-old woman presented with recent onset motor aphasia. Magnetic resonance imaging revealed a left convexity tumor. We performed gross total resection of the tumor, which was pathologically diagnosed as an atypical meningioma. Tumor resection and decompression of the normal cerebral hemisphere improved aphasia. However, 3 days after surgery, her motor aphasia worsened. Computed tomography scan confirmed that the frontal lobe was being compressed by an enlargement of the postoperative tumor cavity. Conservative therapy did not shrink the cavity, and her motor aphasia persisted. Therefore, 21 days after surgery, a drainage tube was inserted into the enlarged cavity using a neuroendoscope, which promoted shrinkage of the cavity and improved her motor aphasia. We suspected that the enlargement of the postoperative cavity was because of the presence of a valve-like structure. CONCLUSIONS: Even though formation of symptomatic cystic lesions after brain tumor resection is rare, neurosurgeons should be aware of such early postoperative complications and their management strategies.

Effect of delayed mild brain hypothermia on edema formation after intracerebral hemorrhage in rats.

Secondary consequences of intracerebral hemorrhage (ICH) including inflammation, edema, and oxidative damage all contribute to cell death after ICH. Brain hypothermia (BH) has been used as an effective neuroprotective treatment in experimental brain ischemia and traumatic brain injury. In this study, we first attempted to evaluate the effect of delayed mild BH (35 degrees C) on brain edema formation 48 hours after ICH. BH was started 3, 6, 12, and 24 hours after the induction of 100 muL of autologous blood into the basal ganglia (hypothermic [HT]; HT3: n = 4, HT6: n = 6, HT12: n = 11, HT24: n = 6) in rats. To examine the protective mechanism of BH, blood-brain barrier (BBB) permeability to Evans blue, accumulation of polymorphonuclear leukocyte, and oxidative DNA damage in the lesion were compared between normothermic (NT) (37 degrees C) and HT6 rats 48 hours after ICH. Finally, neurologic recovery was assessed using behavioral tests in NT and HT6 rats 48 hours after ICH. Brain water content in the ispilateral basal ganglia was significantly reduced with delayed BT compared with NT (n = 7, 81.8 +/- 0.7% v HT3: 78.9 +/- 0.8%, P < .01; HT6: 78.7 +/- 0.6%, P < .01; HT12: 79.4 +/- 1.1%, P < .01; HT24: 80.3 +/- 0.6%, P < .01). The BBB disruption to Evans blue was significantly reduced with BH (HT6: n = 6) compared with NT (n = 6) rats in the ipsilateral basal ganglia (23.0 +/- 5.2 v 42.3 +/- 4.0 ng/g wet tissue, P < .05). HT6 treatment (n = 6) significantly inhibited the accumulation of polymorphonuclear leukocyte compared with NT treatment (n = 6) (0.43 +/- 0.22 v 1.49 +/- 0.61 DeltaAbs/mg tissue, P < .05). HT6 treatment (n = 3) also significantly reduced oxidative DNA damage determined with 8-hydroxyl-2'-deoxyguanosine compared with NT treatment (n = 3) (92 +/- 18 v 40 +/- 7 pg 8-hydroxyl-2'-deoxyguanosine/mug DNA, P < .05). Furthermore, HT6 treatment (n = 5) significantly improved neurologic recovery assessed with forelimb placing score compared with NT treatment (42.0 +/- 5.8 v 12.0 +/- 3.7, P < .05). In conclusion, mild BH significantly reduces the brain edema formation after ICH, even when the BH is applied 24 hours after hematoma induction in rats. Several neuroprotective mechanisms, including reduced BBB disruption, inflammation and oxidative damage, are suggested in this study.

Association between dexmedetomidine use and neurological outcomes in aneurysmal subarachnoid hemorrhage patients: A retrospective observational study.

PURPOSE: Recent studies in animal subarachnoid hemorrhage (SAH) models have reported that dexmedetomidine (DEX) use demonstrates significantly better neurological outcomes. This study aimed to evaluate whether DEX use is associated with favorable neurological outcomes (FO) in SAH patients. MATERIALS AND METHODS: We retrospectively reviewed all SAH patients between 2009 and 2017. We calculated the total dosage of DEX administered for the first 24h after admission. All patients were classified into no use, low dosage, and standard dosage group. Multivariate analysis was performed to clarify the association between DEX use and FO (modified Ranking Scale score of 0-2 at hospital discharge). RESULTS: There were 161 patients with 55.3% of FO. On univariate analysis, there were significant differences with regard to age, Hunt and Kosnik (H&K) grade, and DEX use. Multivariate analysis showed that age, H&K grade, and low dosage DEX (rather than no use) (odds ratio (OR) 3.17; 95% confidence interval (CI), 1.24-8.53; p=0.02) were significantly associated with FO. However, standard dosage DEX was not a significant factor (OR, 0.75; 95% CI, 0.25-2.16; p=0.59). CONCLUSIONS: Low dosage DEX during the first 24h after admission was associated with FO in SAH patients.