Deep learning-based video-analysis of instrument motion in microvascular anastomosis training.

PURPOSE: Attaining sufficient microsurgical skills is paramount for neurosurgical trainees. Kinematic analysis of surgical instruments using video offers the potential for an objective assessment of microsurgical proficiency, thereby enhancing surgical training and patient safety. The purposes of this study were to develop a deep-learning-based automated instrument tip-detection algorithm, and to validate its performance in microvascular anastomosis training. METHODS: An automated instrument tip-tracking algorithm was developed and trained using YOLOv2, based on clinical microsurgical videos and microvascular anastomosis practice videos. With this model, we measured motion economy (procedural time and path distance) and motion smoothness (normalized jerk index) during the task of suturing artificial blood vessels for end-to-side anastomosis. These parameters were validated using traditional criteria-based rating scales and were compared across surgeons with varying microsurgical experience (novice, intermediate, and expert). The suturing task was deconstructed into four distinct phases, and parameters within each phase were compared between novice and expert surgeons. RESULTS: The high accuracy of the developed model was indicated by a mean Dice similarity coefficient of 0.87. Deep learning-based parameters (procedural time, path distance, and normalized jerk index) exhibited correlations with traditional criteria-based rating scales and surgeons' years of experience. Experts completed the suturing task faster than novices. The total path distance for the right (dominant) side instrument movement was shorter for experts compared to novices. However, for the left (non-dominant) side, differences between the two groups were observed only in specific phases. The normalized jerk index for both the right and left sides was significantly lower in the expert than in the novice groups, and receiver operating characteristic analysis showed strong discriminative ability. CONCLUSION: The deep learning-based kinematic analytic approach for surgical instruments proves beneficial in assessing performance in microvascular anastomosis. Moreover, this methodology can be adapted for use in clinical settings.

Characteristics of MRI Findings after Subarachnoid Hemorrhage and D-Dimer as a Predictive Value for Early Brain Injury.

BACKGROUND: The pathological mechanisms of early brain injury (EBI) have remained obscure. Several studies have reported on the neuroradiological findings of EBI. However, to our knowledge, no study has attempted to explore the mechanism of EBI after subarachnoid hemorrhage (SAH). Therefore, this study evaluates whether the initial plasma D-dimer levels were associated with EBI, classifies magnetic resonance imaging (MRI) findings, and speculates about the mechanism of EBI. METHODS: This study included 97 patients hospitalized within 24 h from the onset of nontraumatic SAH. The patients underwent MRI within 0-5 days from onset (before vasospasm) to detect EBI. EBI was radiologically defined as diffusion-weighted imaging (DWI)-positive lesions that appear dark on apparent diffusion coefficient maps, excluding procedure-related lesions. EBI, plasma D-dimer levels, and clinical features were retrospectively investigated. RESULTS: Elevated D-dimer levels were associated with poor outcomes. Patients with EBI had significantly higher D-dimer levels than those without EBI. EBI was detected in 24 patients (27.3%) of all, and in 22 (45%) of 49 patients with World Federation of Neurosurgical Societies (WFNS) grade 4-5 SAH. EBI was frequently observed in the paramedian frontal lobe. There were several types of the pathology in EBI, including widespread symmetrical cerebral cortex lesions, focal cortex lesions, periventricular injury, and other lesions impossible to classify due to unknown mechanisms such as thrombotic complication and microcirculatory disturbance, ultra-early spasm, and spreading depolarization. CONCLUSIONS: This study suggests that D-dimer levels predict poor outcomes in patients with SAH and that EBI was associated high D-dimer levels.

Efficacy of Carotid Artery Stenting Performed under General Anesthesia with Somatosensory Evoked Potential Monitoring.

OBJECTIVES: During carotid artery stenting (CAS), hemodynamics may be affected by the carotid sinus reflex in some cases. Although general anesthesia has been reported to stabilize intraoperative hemodynamics, the patient's neurological condition must be assessed indirectly. Therefore, we investigated the changes in intraoperative hemodynamics and perioperative complications of CAS under general anesthesia and evaluated the efficacy of somatosensory evoked potential (SEP) monitoring in detecting a reduction in perfusion during CAS. MATERIALS AND METHODS: From April 2011 to August 2016,57 consecutive patients who underwent CAS under general anesthesia were evaluated. The follow-up period ranged from 3 to 8 years. During CAS, anesthesiologists monitored and managed the hemodynamics. SEP monitoring was performed during the CAS procedure in all patients. RESULTS: Intraoperative hypotension (systolic blood pressure ≤ 100 mmHg) was evident in 16 patients (28.1%), and 13 patients (22.8%) experienced intraoperative bradycardia; however, all of these cases were promptly managed under general anesthesia. None of the patients showed systolic blood pressure < 50 mmHg from baseline. Regarding perioperative complications, none of the patients exhibited myocardial infarction or postoperative hyperperfusion symptoms, and there was no mortality. Among 21 patients (36.8%) with a decrease in the intraoperative SEP, 3 (5.3%) exhibited transient ischemic symptoms and 1 (1.8%) had postoperative infarction. CONCLUSIONS: CAS under general anesthesia is a safe and effective management option in terms of intraoperative hemodynamic stability. In addition, our findings indicate that SEP monitoring could be helpful in evaluating transient postoperative cerebral ischemia or cerebral infarction after CAS.

[A Case of Positional Vertebral Artery Occlusion due to Physiological Cervical Extension with Occipital Condylar Spur].

Positional vertebral artery occlusion(PVAO)is a mechanical occlusion of the extracranial vertebral artery(VA)due to physiological movement of the head and neck. However, only a few cases of mechanical VA compression due to routine flexion-extension of the neck have been reported. We present a unique case of PVAO due to neck extension with an occipital condylar spur. A 78-year-old man was admitted to our hospital for sudden onset of right hemiparesis and dysarthria. Magnetic resonance imaging(MRI)revealed bilateral occipital and cerebellar infarctions and vessel occlusion extending from the VA to the basilar artery. Mechanic thrombectomy resulted in partial recanalization. Computed tomography angiography(CTA)performed the next day showed spontaneously recanalized left VA with some wall irregularity. CTA in the neck-extended position revealed a severely compressed left VA in its V3 segment, which was attributed to the left occipital condylar spur with degenerative changes of the condyle-C1 facet. Cervical MRI also showed a pseudotumor from the lower clivus to the odontoid process that indicated mechanical stress on the occipitocervical ligaments. An occiput to C2 fusion was performed to stabilize and avoid dynamic vascular compression. Postoperative CTA revealed no evidence of restricted flow with flexion or extension movements of the neck. It should be noted that physiological head and neck movements accompanied by condylar degenerative changes could be a cause of vertebrobasilar insufficiency.

Novel Hemoglobin-Based Oxygen Carrier Bound With Albumin Shows Neuroprotection With Possible Antioxidant Effects.

Background and Purpose- A hemoglobin-albumin cluster, 1 core of hemoglobin covalently bound with 3 shell albumins, designated as HemoAct was developed as a hemoglobin-based oxygen carrier. We aim to investigate neuroprotection by HemoAct in transient cerebral ischemia and elucidate its underlying mechanisms. Methods- Male rats were subjected to 2-hour transient middle cerebral artery occlusion and were then administered HemoAct transarterially at the onset of reperfusion. Neurological and pathological findings were examined after 24 hours of reperfusion to identify neuroprotection by HemoAct. Intermittent measurements of cortical blood flow and oxygen content were performed, and a histopathologic analysis was conducted on rats during the early phase of reperfusion to assess the therapeutic mechanism of HemoAct. In addition, the antioxidant effects of HemoAct were examined in hypoxia/reoxygenation-treated rat brain microvascular endothelial cells. Results- Neurological deterioration, infarct and edema development, and the activation of MMP-9 (matrix metalloprotease-9) and lipid peroxidation after 24 hours of reperfusion were significantly ameliorated by the HemoAct treatment. Reductions in blood flow and tissue partial oxygen pressure in the cortical penumbra after 6 hours of reperfusion were significantly ameliorated by the HemoAct treatment. The histopathologic analysis of the cortical penumbra revealed that HemoAct in HemoAct-treated rats showed superior microvascular perfusion with the mitigation of microvascular narrowing changes than autologous erythrocytes in nontreated rats. Although HemoAct extravasated into the ischemic core with serum protein, it did not induce an increase in serum extravasation or reactive oxygen species production in the ischemic core. In vitro experiments with rat brain microvascular endothelial cells revealed that HemoAct significantly suppressed cellular reactive oxygen species production in hypoxia/reoxygenation-treated cells, similar to albumin. Conclusions- HemoAct exerted robust neuroprotection in transient cerebral ischemia. Superior microvascular perfusion with an oxygen delivery capability and possible antioxidant effects appear to be the underlying neuroprotective mechanisms.

Factors influencing cerebral aneurysm obliteration and reliability of indocyanine green video-angiography.

BACKGROUND: Indocyanine green video-angiography (ICG-V) is commonly used for intraoperative confirmation of aneurysm obliteration following clipping. However, direct puncture of the aneurysm wall occasionally results in blood leakage in patients for whom ICG-V has indicated complete closure. Therefore, the present study aimed to determine the reliability of ICG-V for confirming complete aneurysm closure, and to elucidate the factors underlying aneurysm obliteration and the occurrence of false-negative ICG-V findings. METHODS: Between June 2012 and June 2016, 89 patients (107 aneurysms total) undergoing aneurysm clipping were examined using ICG-V to confirm aneurysm closure. In ICG-V-negative cases, further confirmation of complete aneurysm closure was obtained via direct puncture of the aneurysm wall, except in cases where this procedure was deemed unsafe. To elucidate the possible causes of ICG-V inaccuracies, positive, negative, and false-negative ICG-V findings were compared in terms of aneurysm location (maximum height and length), neck width (parallel and orthogonal directions to the branching vessels), wall thickness around the neck, bifurcation angle, and direction of the clipping closure line. Statistical analyses were performed using the Welsh's t test and Chi-square test. RESULTS: Intraoperative ICG-V detected seven cases of incomplete aneurysm closure (6.5%), defined as positive ICG-V findings. Following direct aneurysm wall puncture, nine patients (8.4%) exhibited false-negative ICG-V findings. A Chi-square test revealed that false-negative ICG-V findings were significantly influenced by the presence of heterogeneous arteriosclerosis, and wall thickening at the clipping site, which were subjectively defined by the surgeon and confirmed by an independent observer, depending on the wall color and hardness, respectively. CONCLUSIONS: Although ICG-V is useful for intraoperative confirmation of aneurysm obliteration, our findings further highlight the risk of false-negative ICG-V findings. Acknowledgement of risk factors is crucial for efficient detection of false-negative ICG-V findings.

Histologically confirmed case of cerebral vasculitis associated with Crohn's disease--a case report.

BACKGROUND: Extraintestinal manifestations in Crohn's disease (CD) are frequent and well recognized. However, neurological involvement secondary to CD is rare, and there have been few histologically confirmed cases of cerebral vasculitis secondary to CD. CASE PRESENTATION: A 58-year-old left-handed man with a history of refractory CD who had fever of over 38 °C, progression of CD symptoms, and Gerstmann's syndrome consulted our hospital. Laboratory data showed elevation of C-reactive protein (CRP) and hypoproteinemia. T2-weighted magnetic resonance imaging (MRI) revealed a right parietal high-intensity lesion. Catheter angiography showed segmental multiple narrowing and occlusion in the distal part of the middle cerebral artery and anterior cerebral artery. Angiography also revealed multiple venous occlusions in the affected parietal area. To confirm the diagnosis, the patient underwent open biopsy, and histological examination revealed cerebral vasculitis. The patient was then started on high-dose prednisolone (60 mg/day) in addition to his previous therapy, which included mesalazine, adalimumab, and azathioprine. CRP elevation, hypoproteinemia, and gastrointestinal symptoms immediately improved after starting this treatment. Neurological status improved simultaneously with CD symptom improvement, and follow-up brain MRI revealed a reduction in the size of the right parietal lobe lesion. He returned to normal status and was discharged from our hospital 5 weeks after admission. CONCLUSION: This is an important case of histologically confirmed cerebral vasculitis associated with CD. The clinical course of our case clearly illustrates the relevance of the occurrence of cerebral vasculitis and the exacerbation of CD.

The montage method improves the classification of suspected acute ischemic stroke using the convolution neural network and brain MRI.

This study investigated the usefulness of the montage method that combines four different magnetic resonance images into one images for automatic acute ischemic stroke (AIS) diagnosis with deep learning method. The montage image was consisted from diffusion weighted image (DWI), fluid attenuated inversion recovery (FLAIR), arterial spin labeling (ASL), and apparent diffusion coefficient (ASL). The montage method was compared with pseudo color map (pCM) which was consisted from FLAIR, ASL and ADC. 473 AIS patients were classified into four categories: mechanical thrombectomy, conservative therapy, hemorrhage, and other diseases. The results showed that the montage image significantly outperformed pCM in terms of accuracy (montage image = 0.76 ± 0.01, pCM = 0.54 ± 0.05) and the area under the curve (AUC) (montage image = 0.94 ± 0.01, pCM = 0.76 ± 0.01). This study demonstrates the usefulness of the montage method and its potential for overcoming the limitations of pCM.

Carotid Endarterectomy for a Case with an Extremely Twisted Internal Carotid Artery.

The internal carotid artery (ICA) typically runs posterolaterally to the external carotid artery (ECA) at the level of the common carotid artery (CCA) bifurcation in the neck. The "twisted ICA" is an anatomical variation, wherein the ICA is medial to the ECA. Several studies on the twisted ICA have discussed its anatomical definition, incidence, clinical features, and surgical results in patients with luminal stenosis. Computed tomography angiography (CTA)-based analyses of surgically treated cohorts documented a twist angle, reaching up to 95°. Carotid endarterectomy (CEA) was successfully performed for these patients. This study reports a case of a significantly twisted ICA with severe luminal stenosis that was successfully treated with CEA. An 81-year-old male was incidentally diagnosed with asymptomatic right ICA stenosis based on magnetic resonance (MR) angiography. Three-dimensional (3D)-CTA showed that the ICA revealed 74% stenosis of the ICA, based on the North American Symptomatic Carotid Endarterectomy Trial criteria. The 3D-CTA showed the ICA medial to the ipsilateral ECA at the level of the CCA bifurcation in the neck. It extended proximally to the pharynx, and the twist angle was 102°. Black-blood MR of the carotid plaque exhibited a high intensity on T1-weighted imaging, indicating vulnerability. Intraoperatively, the position of the ICA was corrected using multiple hooks instead of a surgical retractor. He showed no permanent deficits, such as an ipsilateral cerebral infarction, although transient postoperative hoarseness was observed. This case report documented a significantly twisted ICA with luminal stenosis, successfully treated via CEA, by correcting the carotid position using multiple hooks with gentle manipulation.

Neuroprotective effects of a hemoglobin-based oxygen carrier (stroma-free hemoglobin nanoparticle) on ischemia reperfusion injury.

The application of hemoglobin (Hb)-based oxygen carriers (HBOCs) to the treatment of cerebral ischemia has been investigated. A cluster of 1 Hb and 3 human serum albumins (Hb-HSA3) was found to exert neuroprotective effects on ischemia/reperfusion injury. Stroma-free hemoglobin nanoparticles (SFHbNP), a subsequently developed HBOC consisting of a spherical polymerized stroma-free Hb core with a HSA shell, contains the natural antioxidant enzyme catalase and, thus, is expected to exert additive effects. We herein investigated whether SFHbNP exerted enhanced neuroprotective effects in a rat transient middle cerebral artery occlusion (tMCAO) model. Rats were subjected to 2-hour tMCAO and divided into the following 3 groups with the intravenous administration of the respective reagents: (1) phosphate-buffered saline (PBS), as a vehicle (2) Hb-HSA3, and (3) SFHbNP. After 24-hour reperfusion, infarct and edema volumes decreased in the order of the PBS, Hb-HSA3, and SFHbNP groups, with a significant difference (p < 0.05) between the PBS and SFHbNP groups. Similar reductions were observed in oxidative stress, leukocyte recruitment, and blood-brain barrier disruption in the order of the PBS, Hb-HSA3, and SFHbNP groups. In the early phase of reperfusion within 6 h, microvascular HBOC perfusion and cerebral blood flow were maintained at high levels during the reperfusion period in the Hb-HSA3 and SFHbNP groups. However, a difference was observed in tissue oxygen partial pressure levels, which significantly decreased after 6-hour reperfusion in the Hb-HSA3 group, but remained high in the SFHbNP group. A superior oxygen transport ability appears to be related to the enhanced neuroprotective effects of SFHbNP.

Simultaneous depiction of clot and MRA using 1 min phase contrast angiography in acute ischemic patients.

[Background and Purpose] Clot location and range predict clinical outcomes for acute ischemic stroke (AIS). We developed a new technique for visualizing occlusion clots, namely, the DEpicting blood clot and MRA using Phase contrast angiography with Image Calculation for Thrombectomy (DEPICT) method. The purpose of this study was to assess the clinical usefulness of DEPICT. [Methods] We used DEPICT in 36 AIS patients to obtain MRA and black blood images with 1-min phase contrast angiography (PCA). We created the black blood images by subtracting the MRA from the T1WI using the source image of PCA. We evaluated the motion artifact, detectability of clot, and precision in location and range compared these to that of susceptibility vessel sign in T2*WI and measured contrast ration (CR) of clot between the cistern and brain tissue. Motion artifact was visually evaluated using a 3-point scale. Detectability and precision of the location and range of occlusion clots were assessed by comparison with findings from digital subtraction angiography (DSA). Gwet's AC1 and kappa statistics were used to assess inter-observer agreement. [Results] DEPICT showed significant robustness for motion artifact compared with T2*WI (p = 0.0026, Wilcoxon signed-rank test). DEPICT showed 100% detectability for the clot. Further, DEPICT showed higher Gwet's AC1 and kappa statistic values with DSA than T2*WI. CR demonstrated a positive value. [Conclusions] DEPICT technique based on 1-min PCA offers both MRA and black blood T1W images that can be used to accurately evaluate both location and range of the clot.

Induction of large cerebral aneurysms by intraperitoneal administration of ß-aminopropionitrile fumarate in male rats.

BACKGROUND: It is necessary and useful to obtain an experimental model which steadily and rapidly induces aneurysms for investigation of the pathogenesis of cerebral aneurysm. We attempted to examine whether intraperitoneal administration of ß-aminopropionitrile fumarate (BAPN-F) with additional treatments of induced hypertension and hemodynamic stress could steadily and rapidly induce aneurysms in male rats. METHODS: Seven-week-old male Sprague-Dawley rats pretreated with ligation of left common carotid and bilateral posterior renal arteries were administrated BAPN-F intraperitoneally. Induction rate and size of aneurysms was investigated with varying dose and duration of BAPN-F administration (low dose; 400 mg/kg/week for 4 or 8 weeks and high dose; 2800 mg/kg/week for 8 or 12 weeks). RESULTS: Induction rate in the high-dose groups was significantly higher (P<0.01) than that in the low-dose groups. Making comparisons between 8 and 12 weeks of the high-dose groups, while there was no difference in induction rate (8 weeks; 85.2% vs. 12 weeks; 76.9%), aneurysmal size was larger in 12 weeks (8 weeks; 127.5 µm, vs. 12 weeks; 181.7 µm in terms of median) but lethal intrathoracic hemorrhage was increased in 12 weeks (8 weeks; 7.4% vs. 12 weeks; 30.8%). Induction rate of large aneurysm was 22.2% and 30.8% in 8 and 12 weeks of the high-dose groups, respectively. CONCLUSIONS: High-dose BAPN-F administration can cause high-frequency aneurysmal induction. Although there was the difference in size and mortality rate based on administration duration, intraperitoneal administration of 2800 mg/kg/week BAPN-F for 8 weeks would be suitable for aneurysmal induction.

Acute systematic inflammatory response syndrome and serum biomarkers predict outcomes after subarachnoid hemorrhage.

Subarachnoid hemorrhage (SAH) can trigger immune activation sufficient to induce systematic inflammatory response syndrome (SIRS). Serum inflammatory biomarkers and SIRS can predict a poor outcome. The relationship between surgical stress and inflammatory response is well known but described in few reports in the neurosurgical population. We aimed to ascertain whether postoperative SIRS and initial serum biomarkers were associated with outcomes and evaluate whether the postoperative SIRS score differed between those with clipping and coil embolization. We evaluated 87 patients hospitalized within 24 h from onset of nontraumatic SAH. Serum biomarkers, such as levels of C-reactive protein (CRP), white blood cells (WBC), and D-dimer, as well as stress index (SI: blood sugar/K ratio) were obtained at admission. SIRS scores 3 days after admission were derived by adding the number of variables meeting the standard criteria (heart rate [HR] >90, respiratory rate [RR] >20, temperature >38 °C or <36 °C, and WBC count <4000 or >12,000). Clinical variables were compared according to whether they were associated with poor outcomes. Coil embolization was performed in 30 patients and clipping in 57. WBC, SI, D-dimer levels, and SIRS scores were significantly higher in patients with poor-grade SAH and were associated with poor outcomes. SIRS scores were significantly higher with clipping than with coil embolization among patients with good-grade SAH without intracerebral hemorrhage. Acute SIRS and serum biomarkers predict outcomes after SAH. Moreover, our study suggests the influence of surgical invasion via clipping on SIRS after SAH.

Neuroprotective effects of combination therapy of regional cold perfusion and hemoglobin-based oxygen carrier administration on rat transient cerebral ischemia.

Regional cold perfusion and hemoglobin-based oxygen carrier administration both exert neuroprotective effects against cerebral ischemia reperfusion injury. We herein investigated whether the combination of these two therapies leads to stronger neuroprotective effects. Combination therapy was performed with the regional perfusion of cold HemoAct, a core-shell structured hemoglobin-albumin cluster, in a rat transient middle cerebral artery occlusion model. The effects of combination therapy, the intra-arterial administration of 10 °C HemoAct (10H) initiated at the onset of reperfusion, were compared with those of monotherapies, the intra-arterial administration of 10 °C saline (10S) and 37 °C HemoAct (37H), and an untreated control under the condition of 2-hour ischemia/24-hour reperfusion. The durability of therapeutic effects and the therapeutic time window of combination therapy were assessed based on comparisons with the 10H and control groups. Significantly better neurological findings and smaller infarct volumes were observed in the three treated (10S, 37H, and 10H) groups than in the control group. Among the 3 treated groups, only the 10H group showed significant improvements over the control group in the other items examined, including cerebral blood flow reduction, brain edema, and protein extravasation. The significant therapeutic effects of combination therapy on neurological disabilities and infarct volumes were confirmed at least until 7 days after reperfusion. Furthermore, combination therapy ameliorated neurological disabilities and hemorrhagic transformation in rats subjected to 4- and 5-hour ischemia/24-hour reperfusion. Since therapeutic effects may be expected until at least 5 h of complete ischemia and reperfusion, this combination therapy is a promising neuroprotective strategy against severe ischemic stroke.

Transarterial regional hypothermia provides robust neuroprotection in a rat model of permanent middle cerebral artery occlusion with transient collateral hypoperfusion.

The robust neuroprotective effects of transarterial regional hypothermia have been demonstrated in the typical transient middle cerebral artery occlusion (tMCAO) model, but have not yet been tested in other ischemic stroke models, even though clinical ischemic conditions are diverse. In order to clarify these effects in a different ischemic stroke model, we employed a rat model of permanent MCAO (pMCAO) with transient collateral hypoperfusion (tCHP), which was achieved by direct MCA ligation through craniotomy and 1-h bilateral common carotid artery occlusion at the beginning of pMCAO. The infusion of 20ml/kg of 4°C cold saline (CS) or 37°C warm saline (WS) into the ipsilateral internal carotid artery (ICA) was performed for 15min in intra- or post-tCHP. Neurological scores, infarct/edema volumes, and neuronal apoptosis and reactive gliosis were compared between the CS and WS groups and a non-infusion control group after 48h of reperfusion. Although brain temperatures were only reduced by 2-3°C for 15min, the CS group had significantly better neurological scores, smaller infarct/edema volumes, and less penumbral neuronal apoptosis and reactive gliosis than the control and WS groups. The post-tCHP CS group exhibited prominent neuroprotective effects, even though infarct volumes and neuronal apoptosis were reduced less than those in the intra-tCHP CS group. In conclusion, we demonstrated the neuroprotective effects of transarterial regional hypothermia in an ischemic model of pMCAO with tCHP. Even though MCAO is persistent, cold infusion via the ICA is neuroprotective for the penumbra, suggesting the wider therapeutic application of this therapy.

Surgical management of combined intramedullary arteriovenous malformation and perimedullary arteriovenous fistula within the hybrid operating room after five years of performing focus fractionated radiotherapy: case report.

Perimedullary arteriovenous fistula (AVF) shunts occur on the spinal cord surface and can be treated surgically or by endovascular embolization. In contrast, the nidus of an intramedullary arteriovenous malformation (AVM) is located in the spinal cord and is difficult to treat surgically or by endovascular techniques. The benefits of radiotherapy for treating intramedullary AVM have been published, but are anecdotal and consist largely of case reports. We present a case of combined cervical intramedullary AVM and perimedullary AVF which received surgical treatment within a hybrid operating room (OR) after 5 years of focus fractionated radiotherapy. A 37-year-old male presented with stepwise worsening myelopathy. Magnetic resonance imaging and spinal angiography revealed intramedullary AVM and perimedullary AVF at the C3 to C5 levels. In order to reduce nidus size and blood flow, we first performed focal fractionated radiotherapy. Five years later, the lesion volume was reduced. Following this, direct surgery was performed by an anterior approach using corpectomy in the hybrid OR. The spinal cord was monitored by motor-evoked potential throughout the surgery. Complete obliteration of the fistulous connection was confirmed by intraoperative indocyanine green video-angiography and intraoperative angiography, preserving the anterior spinal artery. We conclude that surgical treatment following focal fractionated radiotherapy may become one strategy for patients who are initially deemed ineligible for endovascular embolization and surgical treatment. Furthermore, the hybrid OR enables safe and precise treatment for spinal vascular disorders in the fields of endovascular treatment and neurosurgery.

Hemorrhagic onset of hemangioblastoma located in the dorsal medulla oblongata presenting with tako-tsubo cardiomyopathy and neurogenic pulmonary edema: a case report.

Here, we present a case of dorsal medulla oblongata hemangioblastoma with fourth ventricular hemorrhage. A 23-year-old female developed sudden consciousness disturbance, and CT revealed hemorrhage in all cerebral ventricles and a hyperdense mass in the cisterna magna. Although the reddish tumor located in the dorsal medulla oblongata was successfully removed, she suffered from severe tako-tsubo cardiomyopathy (TTC) and neurogenic pulmonary edema (NPE) because of baroreflex failure and damage to the solitary tract nuclei. After intensive care for 12 weeks following surgery, she was discharged without any neurological or radiological deficits. Pathogenesis of TTC/NPE is discussed in this paper.