Expert Consensus on the Management of Brain Arteriovenous Malformations

Brain arteriovenous malformations (bAVMs) are complex, heterogeneous, and uncommon intracranial lesions. They can be treated by one or a combination of the following treatment modalities, namely embolization, radiosurgery, or microsurgical resection. In Spetzler-Martin Grade 4 and 5 arteriovenous malformations (AVMs), conservative management may be the best option. A group of experts in the management of AVMs of different disciplines gathered in January 2019 in Hanoi to compile the “Expert Consensus on the Management of Brain Arteriovenous Malformations”.

Effectiveness of Low-Dose Intravenous Fentanyl for Postoperative Headache Management After Neck Clipping of Ruptured Intracranial Aneurysms

BACKGROUND

After subarachnoid hemorrhage (SAH), headache management is often difficult owing to the need to use multiple analgesic drugs. Fentanyl is an opioid we can use after surgery, and it can decrease pain post SAH. The aim of this study was to investigate the effectiveness and safety of fentanyl for management of headache after SAH.

METHODS

Twenty-two patients who underwent surgical clipping for ruptured intracranial aneurysms and complained of severe headache after the surgery were enrolled. Among them, 9 patients were given fentanyl combined with other analgesic drugs. The numeric rating scale score and dietary intake were measured in the acute phase after the SAH.

RESULTS

The numeric rating scale scores were significantly lower in the fentanyl (+) group. The maximum numeric rating scale decreased to <5 points within 16.5 ± 2.9 days in the fentanyl (-) group and within 12.0 ± 2.6 days in the fentanyl (+) group. The median numeric rating scale decreased to <5 points over 14.0 ± 4.2 days in the fentanyl (-) group and >7.7 ± 3.8 days in the fentanyl (+) group. At day 14, the fentanyl (+) group showed significantly better dietary intake than that of the fentanyl (-) group.

CONCLUSIONS

Using fentanyl after surgical clipping for ruptured intracranial aneurysms might decrease headache and produce few adverse effects. Adequate headache control showed improved dietary intake after SAH.

Dural Sinus Thrombosis with Nonsymptomatic Persistent Falcine Sinus: A Case Report

A 24-year-old woman was admitted to our hospital after convulsive status epilepticus. A cerebral magnetic resonance venography revealed a persistent fetal falcine sinus. Additionally, the posterior third of the superior sagittal sinus was hypoplastic and the abnormal deep venous drainage was accompanied. These abnormalities had already been detected by magnetic resonance imaging several years ago. In the present scan, we discovered a sinus thrombosis in the hypoplastic superior sagittal sinus. In the cerebral angiography, we observed delayed venous return in the left parieto-occipital lobe and hypothesized that cerebral venous stasis due to the thrombus caused the convulsive status epilepticus. The patient was treated with intravenous administration of heparin along with an antiepileptic drug, and she recovered with no neurological defects. In the present case, the falcine sinus and the anomalous venous return were likely congenital while the status epilepticus was derived from thrombosis in the hypoplastic superior sagittal sinus. Although the falcine sinus functioned as an alternative pathway for the superior sagittal sinus, the hypoplastic superior sagittal sinus itself may also play an important role as a venous drainage channel.

Treatment Outcomes of Cerebral Aneurysms Presenting with Optic Neuropathy: A Retrospective Case Series

Background:

Optic neuropathy due to an aneurysm is relatively rare, with only a few small case series on this topic, and no randomized trials having been published until now. As such, the functional prognosis and treatment for aneurysm-induced optic neuropathy remain controversial.

Objective:

We quantified optic nerve injuries using an objective index (the visual impairment score) and evaluated prognostic factors of postoperative visual function.

Materials and Methods:

Of 960 patients treated for an unruptured intracranial aneurysm, 18 (1.9%) patients had optic neuropathy. Visual acuity and visual field were assessed before surgery and 6 months’ postoperatively. Cases were classified on the basis of treatment modality (coil embolization or flow alteration [FA]) and prognostic factors of the two treatment groups.

Results:

Of the 18 patients with an intracranial aneurysm and optic neuropathy, 12 (67%) were treated using coil embolization and 6 (33%) were FA. Visual function improved after surgery in 8 patients (44%), 5 (42%) in the coil embolization group, and 3 (50%) in the FA group. The visual function remained stable after surgery in 6 (33%) patients and worsened in 4 (22%). Patients with an aneurysms <15 mm in size had a favorable outcome (P = 0.05).

Conclusions:

Surgical treatment improved vision in 44% of cases, with no difference in the prognosis of coil embolization and FA and no effect of the duration of symptoms on outcomes. Further, the prognosis of visual function recovery was better for aneurysms <15 mm in diameter.

The Visualization Methods of Occluded Dural Sinus for Safe Transvenous Embolization of Dural AVFs

BACKGROUND

Transvenous embolization (TVE) via occluded sinus is one option for the treatment of dural arteriovenous fistulas. Understanding of the anatomical characteristics of the occluded sinus is difficult. It is often hard to reach the shunt point because of some risk of vessel perforation.

METHODS

We assessed usefulness of T1 Volumetric Isotropic TSE Acquisition (VISTA) Black Blood (BB) and 3D-T1 Fast Field Echo (FFE) for the evaluation and visualization of an occluded sinus. Evaluation of T1 VISTA BB and 3D-T1 FFE was performed preoperatively. TVE was performed via the occluded sinus while referring to the visualized reconstruction image.

RESULTS

Fourteen cases of TVE were performed between 2009 and 2015. The entire occluded sinus, including both thrombus and blood flow, was seen as the high-intensity region on 3D FFE T1 gadlinium (Gd). On the other hand, thrombus was seen as the iso- or high-intensity region and blood flow as the low-intensity region on T1 VISTA BB. The maximum intensity projection reconstruction image of 3D FFE T1Gd could visualize the whole occluded sinus and was useful for microcatheter maneuver. Total shunt obliteration was achieved in 13 cases (92.8%) except for one.

CONCLUSIONS

Magnetic resonance imaging evaluation of the occluded sinus using both T1 VISTA BB and 3D FFE T1Gd gives us valuable information of the occluded sinus regarding the development and the course of the occluded sinus, the length of the thrombotic occlusion, and leads to safer catheter maneuvers in TVE.

Transvenous Embolization of Dural Arteriovenous Fistula of the Anterior Condylar Confluence via the Intercavernous Sinus Assisted by Bone Subtraction Computed Tomography Angiography

BACKGROUND

Dural arteriovenous fistulae (dAVFs) of the anatomically complex anterior condylar confluence (ACC) are often examined by computed tomography (CT) angiography and conventional angiography before treatment. Contrasted vessels often overlap with skull bones in enhanced CT scan and make it difficult to detect the shunt point of the dAVF. Bone subtraction CT angiography (BSCTA) can overcome this limitation and allow for superior imaging of dAVFs that may help to find an alternative access for catheterization.

CASE DESCRIPTION

An 80-year-old woman suffered from right ear tinnitus, headache, and an audible bruit. Preoperative imaging showed a dAVF of the ACC. It was fed by the bilateral ascending pharyngeal artery, drained to the internal jugular vein (IJV) via the inferior petrosal sinus, and had an intraosseous shunt pouch. We therefore performed transvenous embolization (TVE) via the intercavernous sinus because the angle between the anterior condylar vein and the IJV was too sharp to catheterize vessels through the ipsilateral IJV.

CONCLUSIONS

Understanding the inherently complex and individually unique venous anatomy of the ACC is crucial for treatment of dAVFs. BSCTA is an effective visualization technique for dAVFs of the ACC and allows for precise preoperative vascular structure evaluation. We suggest that in the case of the angle between the ACV and the IJV being too sharp to catheterize vessels through the ipsilateral IJV, TVE via the intercavernous sinus can be efficiently used.

[Dissecting Internal Carotid Aneurysm Causing Epistaxis:A Case Report]

We report a rare case of a ruptured dissecting internal carotid aneurysm caused epistaxis without a history of trauma or infection. An 89-year-old woman experienced epistaxis and suffered from hemorrhagic shock at her previous hospital. Head computed tomography(CT)images revealed a ruptured internal carotid aneurysm protruding into the Onodi cell, the most posterior ethmoidal sinus, which extends superolaterally to the sphenoid sinus. Cerebral angiography demonstrated a multilobular-shaped dissecting aneurysm with a maximal diameter of 6.7mm at the cavernous portion of the internal carotid artery(ICA). Overlapping stenting was performed to prevent recanalization. However, a fatal subarachnoid hemorrhage occurred 2 days after the procedure due to the progression of the dissection to the intracranial ICA. The anatomical characteristics of the ethmoidal sinus could be associated with the occurrence of epistaxis. A ruptured small ICA aneurysm with an Onodi cell might cause epistaxis without a history of trauma or infection.

Spinal Cord Infarction in the Region of the Posterior Spinal Artery After Embolization for Vertebral Artery Dissection

BACKGROUND

Endovascular surgery for vertebral artery dissections (VADs) carries the risk of spinal cord infarction (SCI). Although SCI in the region of the anterior spinal artery (ASA) has been reported, SCI in the region of the posterior spinal artery (PSA) is rare.

OBJECTIVE

To investigate PSA infarction after endovascular surgery for VAD.

METHODS

Infarction in the region of the PSA after endovascular surgery for VADs carried out in consecutive 21 cases was investigated. The variables of aneurysmal location, status, intra-aneurysmal thrombosis, antithrombotic therapy, and endovascular procedure were investigated in relation to the occurrence of spinal cord or brain stem infarction.

RESULTS

Thirteen cases were unruptured aneurysms, and 8, ruptured aneurysms. The endovascular surgical method was internal trapping in 10 cases, stent-assisted coil embolization in 8 cases, and proximal occlusion (PO) in 3 cases. Periprocedural symptomatic infarction was detected in 4 of the 21 cases (19%): 3 SCIs and 1 lower medulla infarction, after 1 stent-assisted coil embolization and 3 PO. All 3 symptomatic SCIs were PSA infarction. On univariate analysis, the variables of posterior inferior cerebellar artery-involved-type, PO, and intraprocedural proximal flow arrest were significantly correlated with occurrence of PSA infarction.

CONCLUSION

PSA infarction after endovascular surgery for VAD seems not to be a rare potential complication. Insufficiency of collateral blood flow and artery-to-artery embolism due to intraprocedural flow stagnation of the VA seem to be the possible mechanisms of PSA infarction in addition to previously reported mechanisms such as direct obliteration by the embolic materials and extended thrombosis of the VA stump.

[A Case of Kanji Agraphia Resulting from Intracerebral Hemorrhage on the Left Temporal Lobe Associated with Multiple Dural Arteriovenous Fistulas]

A 60-year-old, right-handed man suffered from mild word finding difficulties and kanji agraphia. Brain computed tomography revealed left temporal lobe hemorrhage, and cerebral angiogram revealed multiple dural arteriovenous fistulas (d-AVFs) in the left anterior cranial fossa and middle cranial fossa. Surgical shunt ablation was performed, and the lesions were obliterated completely. Analysis of the kanji agraphia during neuropsychological rehabilitation showed similar symptoms to those of the left posterior inferior temporal lobe lesion. Re-evaluation of magnetic resonance imaging showed multiple microbleeds on the left inferior temporal lobe, which could be responsible for the kanji agraphia. In this case, analysis of clinical symptoms with careful neuropsychological examination was important for understanding these pathologies. (Received March 21, 2017; Accepted June 21, 2017; Published December 1, 2017).

[A Case of Ruptured Anterior Communicating Artery Aneurysm with Visual Field Defects and Deteriorating to Severe Vision Loss]

Although Terson's syndrome is a well-known cause of vision loss due to intracerebral aneurysm rupture, optic nerve neuropathy can also occur because of other causes. Here, we report such a case, i.e., a ruptured anterior communicating artery aneurysm accompanied by vision loss and visual field disturbances due to a cause other than Terson's syndrome. A 47-year-old man presented with right superior altitudinal hemianopia. Computed tomography (CT) showed subarachnoid hemorrhage (SAH), and three-dimensional CT angiography revealed an anterior communicating artery aneurysm. Coil embolization was performed. Right visual acuity degenerated to blindness in the acute stage. MRI performed on day 7 post-admission revealed that the aneurysm had swollen and made contact with the right optic disk. On the basis of the patient's clinical course, we believe that the deterioration in his visual acuity could have been due to ischemic optic neuropathy (ION) resulting from SAH, and the subsequent edema and poor blood perfusion may be attributed to spasm. In cases of visual disturbance associated with SAH, as in our case, it is important to perform MRI to evaluate the damage or risk to the optic nerve as soon as possible. (Received December 26, 2016; Accepted June 9, 2017; Published October 1, 2017).

Phase I/II clinical trial to assess safety and efficacy of intratumoral and subcutaneous injection of HVJ-E in castration-resistant prostate cancer patients

Inactivated Sendai virus particles (hemagglutinating virus of Japan envelope (HVJ-E)) have a novel antitumor effect: HVJ-E fused to prostate cancer cells via cell surface receptor causes apoptosis of prostate cancer cells in vitro and in vivo. HVJ-E also induces antitumor immunity by activating natural killer (NK) cells and cytotoxic T cells and suppressing regulatory T cells in vivo. We conducted an open-label, single-arm, phase I/II clinical trial in patients with castration-resistant prostate cancer (CRPC) to determine the safety and efficacy of intratumoral and subcutaneous injection of HVJ-E. Patients with CRPC who were docetaxel-resistant or could not receive docetaxel treatment were eligible. HVJ-E was injected directly into the prostate on day 1 and subcutaneously on days 5, 8 and 12 in two 28-day treatment cycles using a 3+3 dose-escalation design. The primary end points were to evaluate safety and tolerability of HVJ-E. The secondary end points were to analyze tumor immunity and antitumor effect. The study is registered at UMIN Clinical Trials Registry, number UMIN000006142. Seven patients were enrolled, and six patients received HVJ-E. Grade 2 or 3 adverse events (Common Terminology Criteria for Adverse Events Ver. 4.0) were urinary retention and lymphopenia from which the patients recovered spontaneously. No Grade 4 adverse events were observed. Radiographically, three patients had stable disease in the low-dose group, and one patient had stable disease and two had progressive disease in the high-dose group. The prostate-specific antigen (PSA) declined from 14 to 1.9 ng ml^-1 in one patient in the low-dose group after two cycles of HVJ-E treatment, and the PSA response rate was 16.6%. NK cell activity was elevated from day 12 to day 28 after HVJ-E administration, whereas serum interleukin-6, interferon (IFN)-α, IFN-β and IFN-γ levels were not affected by HVJ-E treatment. Intratumoral and subcutaneous injections of HVJ-E are feasible and PSA response was observed in a subgroup of CRPC patients.

[Dural Arteriovenous Fistula with Acute Visual Loss Manifestation:A Case Report]

In this report, we are describing a rare case of dural arteriovenous fistula(DAVF)followed by an isolated symptom of bilateral visual acuity disturbance. The patient was a 67-year-old man suffering from progressive bilateral visual acuity disturbance. Angiography revealed a diffuse arteriovenous fistula in the left transverse-sigmoid sinus affected by severe venous congestion. Visual acuity disturbance is likely to have been caused by increased intracranial pressure(IICP). Venous congestion as well as visual acuity were gradually improved following three transarterial embolizations. It is possible that a gradual progression of the clinical condition has caused only visual acuity disturbance without any other IICP symptoms, which is similar to pseudotumor cerebri. Should an unexplained visual acuity loss occur, the case should be investigated by considering DAVF.

Morphological and Immunohistochemical Features of Cryptosporidium andersoni in Cattle

Light and electron microscopic features and immunohistochemical features of Cryptosporidium andersoni ( C. andersoni) and host reaction in the mucosa were studied. Although the affected cattle demonstrated no apparent clinical signs, a severe infection of C. andersoni was observed in the abomasum. C. andersoni were round in shape, measured 6-8 μm in size and were mainly observed to be freely located in the gastric pits, being attached in occasional cases to the surface of the abomasum epithelium. Frequent inflammatory cells had infiltrated the lamina propria of the affected mucosa, and frequent mitotic figures were observed in epithelial cells at the dilated isthmus. To access the cell kinetics, the number of epithelial cells infected with C. andersoni were counted and compared with noninfected cattle. The number of gastric pit cells in infected cattle was significantly higher than that in the controls. The number of proliferative cells determined by the Ki-67 antigen in C. andersoni infected cattle was also significantly higher than that in the controls. Transmission electron microscopy and scanning electron microscopy revealed that the morphology of the C. andersoni organism was common to those of other Cryptosporidium spp. immunohistochemically, several commercial antibodies against Cryptosporidium spp. showed positive reactions at the wall of these oocysts or parasitophorous vacuoles. This report is possibly the first to discuss the prominent hyperplasia of the abomasum mucosa, as well as morphologic features of C. andersoni in cattle.