Koji Tokunaga, Krisztina Barath, Jean-Baptiste Martin and Daniel A. Rüfenacht
✓ Transarterial particulate embolization is indicated for benign intracranial dural arteriovenous fistulas (DAVFs) that have no dangerous venous reflux. This treatment, however, does not cure these lesions. In this case report the authors describe a spontaneously occurring DAVF that was treated by implanting coils through a transarterial microcatheter into the affected venous channel. The channel was separate from the normal dural sinuses. The pathological architecture of the fistula and the usefulness of this approach are discussed.
Michael D. Partington, Daniel A. Rüfenacht, W. Richard Marsh and David G. Piepgras
✓ The authors report a series of seven patients with myelopathy who were found to have spinal dural arteriovenous (AV) fistulas in which the nidus was located at some distance from the spinal cord. The nidus was intracranial in three cases and involved a sacral nerve root sheath in the other four, in each case, the arterialized draining vein led into the coronal plexus of medullary veins. A lack of normal draining radicular veins was noted in all cases. Magnetic resonance images were obtained in four patients and demonstrated spinal cord tissue changes only in the lower thoracic cord in three cases and in the cervical cord in one, all consistent with an ischemic process secondary to venous hypertension. Five patients were managed surgically by division of the draining vein, with improvement of the neurological deficit in all. One patient was treated by embolization alone and had stabilization of her deficit. The remaining patient in the series died of unrelated systemic disease before the spinal dural AV fistula could be treated.
These cases support the theory that venous hypertension is the dominant pathophysiological mechanism involved in spinal dural AV fistulas independent of their location. In patients with a suspected spinal dural AV fistula, lumbar and thoracic spinal angiography will reveal the site of the fistula in the majority of cases (88% in this series). In the remaining patients, the possibility of a remote fistula must be considered. The lack of normal venous drainage of the cord following injection in the artery of Adamkiewicz is the most reliable indicator of venous hypertension in the cord and can be helpful in making the decision to proceed with a search for a cranial or sacral arterial supply.
Amir R. Dehdashti, Bénédict Rilliet, Daniel A. Rufenacht and Nicolas de Tribolet
Object. This study was designed to determine whether the frequency of shunt-dependent hydrocephalus in patients suffering from aneurysmal subarachnoid hemorrhage (SAH) differs when comparing surgical clip application with endovascular obliteration of ruptured aneurysms.
Methods. In this prospective nonrandomized study, 245 patients with aneurysmal SAH treated using either surgical clip application or endovascular coil embolization were studied at our institution between September 1997 and March 2003. One hundred eighty patients underwent clip application and 65 had coil embolization. In those patients who underwent clip application of anterior circulation aneurysms, the lamina terminalis was systematically fenestrated.
The occurrence of acute, asymptomatic, and shunt-dependent hydrocephalus was analyzed in both treatment groups. A subgroup analysis of patients with good clinical grade (World Federation of Neurosurgical Societies [WFNS] Grades I–III) and better Fisher Grade (1–3) and of patients with Fisher Grade 4 hemorrhage was performed.
Acute hydrocephalus was observed in 19% of surgical cases and 46% of endovascular ones. The occurrence of asymptomatic hydrocephalus was similar in both treatment groups (p = 0.4). Shunt-dependent hydrocephalus occurred in 14% of surgical cases and 19% of endovascular cases. This difference did not reach statistical significance (p = 0.53). Logistic regression models controlling for patient age, WFNS grade, Fisher grade, and acute hydrocephalus in patients with good clinical grade and better Fisher grade revealed no significant difference in the rate of shunt-dependent hydrocephalus in both therapy groups (odds ratio [OR] 0.8, 95% confidence interval [CI] 0.2–2.65). Results of similar models indicated that among patients with intraventricular hemorrhage (IVH), surgical clip application carried a lower risk of shunt-dependent hydrocephalus (OR 0.32, 95% CI 0.14–0.75) compared with that for endovascular embolization.
Conclusions. Shunt-dependent hydrocephalus was comparable in the two treatment groups, even in patients with better clinical and radiological grades on admission. Only patients in the endovascular therapy group who had experienced IVH showed a higher likelihood of shunt-dependent hydrocephalus.
Kenji Sugiu, Jean-Baptiste Martin, Beatrix Jean and Daniel A. Rüfenacht
✓ In this article the authors describe a rescue balloon procedure for coil implantation in three cases. In each patient, the coil seemed likely to unravel. The coils stretched when attempts were made to remove the partially implanted but trapped device. The inflation of a nondetachable microballoon in front of the aneurysm orifice allowed the surgeons to complete implantation of the coil and to avoid a more forceful and potentially harmful retrieval. This rescue balloon method may be useful for emergency situations, such as coil stretching with or without migration.
Jacques Théron, Léopoldo Guimaraens, Oguzman Coskun, Thérésa Sola, Jean-Baptiste Martin and Daniel A. Rüfenacht
The authors report the complications that occurred in their experience with performing recanalization procedures in the internal carotid artery and present their treatment strategies. The complications can be classified into those that were periprocedural and those that were postprocedural. The former include complications related to the vascular-approach access site of and those associated with the dilation and stenting procedure. Other complications observed included embolic events, dissection, vascular spasm, bradycardia, inappropriate dilation, occlusion of the external carotid artery, and rare, unusual complications such as the occurrence of iatrogenic cavernous carotid fistula. Postprocedure complications occurred in the hours and days following the procedure in the form of embolic and occlusive events, and hypotension and bradycardia were seen as late complications in the months following the procedure. The authors discuss how such complications occur and provide suggestions on how to avoid them. The role of stent placement and the potential use of protective devices are explored. Overall, adequate use of currently available systems allows for safe application of endovascular treatment techniques that avoid altogether or treat these potential complications. A reduced incidence of complications related to the initial individual learning curve may be obtained with preclinical training, in which use of invitro models should be considered. Surgical standby no longer seems required; however, early posttreatment surveillance in intensive care unit is mandatory to avoid the remaining primary complications.
Francis H. Tomlinson, Daniel A. Rüfenacht, Thoralf M. Sundt Jr., Douglas A. Nichols and Nicolee C. Fode
✓ Arteriovenous (AV) fistulas of cerebral and spinal arteries are characterized angiographically by an immediate AV transition without a capillary bed or “nidus” as occurs in AV malformations (AVM's). The clinical presentation, morphology, radiology, and treatment of 12 patients with cerebral AV fistulas and of 12 patients with spinal AV fistulas are reviewed. In the patients with cerebral lesions, headache and seizure disorders were the most common presentations followed by subarachnoid hemorrhage, cardiac failure, progressive neurological dysfunction, and incidental detection on prenatal ultrasound study. In patients with spinal AV fistulas, weakness and sensory disturbance in the lower extremities were the most frequent clinical presentations followed by back pain, disturbances of micturition, and grand mal seizure. The etiology of the symptom complex produced by AV fistulas in each of these locations differed, with venous hypertension being important in spinal cord lesions.
Of the patients with cerebral lesions, nine had a single AV fistula, one had two fistulas, and two had multiple fistulas. An AVM was observed in five patients with fistulas (two large, three small). Nine patients exhibited extramedullary AV fistulas of the spine, of whom eight had a single fistula and one had three fistulas; three patients had intramedullary spinal AV fistulas. An arterial aneurysm was found in association with two fistulas, one cerebral and one spinal. Venous ectasias or varices, frequently exhibiting mural calcification, were observed to be prominent in all AV fistulas involving cerebral arteries and in two involving spinal arteries. The location and size of the venous complexes reflected the diameter of the fistula. In addition to conventional imaging techniques (cerebral angiography, computerized tomography, and magnetic resonance (MR) imaging), MR angiography was a helpful adjunct in the evaluation of fistulas. Treatment strategies employed for AV fistulas in both locations included open surgical and endovascular procedures, frequently used in combination. A satisfactory outcome was observed in all patients.
Francis H. Tomlinson, David G. Piepgras, Douglas A. Nichols, Daniel A. Rüfenacht and Sue C. Kaste
✓ A neonate presented with anatomically discrete cerebral arteriovenous fistulae located in the right sylvian fissure and the cerebellar vermis that were initially detected by prenatal ultrasonography. Following delivery of the baby by Caesarean section, both malformations were treated by surgical obliteration. These intracranial vascular lesions were associated with cardiac anomalies and a periductal coarctation of the aorta, which was treated with a left subclavian rotational arterial pedicle repair. Follow-up examination of the infant at age 13 months demonstrated an excellent clinical result with normalization of the circulation. The pathophysiology of this syndrome is discussed and the literature reviewed.
Pavlina Lenga, Christian Hohaus, Bujung Hong, Adisa Kursumovic, Nicolai Maldaner, Jan-Karl Burkhardt, Philippe Bijlenga, Daniel A. Rüfenacht, Nils O. Schmidt, Peter Vajkoczy, Julius Dengler and on behalf of the Giant Intracranial Aneurysm Registry Study Group
Giant posterior circulation aneurysms (GPCirAs) usually cause substantial mass effect on the brainstem, which may lead to neurological deficits. So far, there has been no systematic investigation of factors associated with such deficits in GPCirA. The authors aim to examine the risk factors for cranial nerve deficit (CND), motor deficit, and disability in patients with GPCirA.
Using MR images obtained in 30 patients with unruptured GPCirA, the authors examined GPCirA volume, presence of hydrocephalus or partial thrombosis (PT) of the aneurysm, and the degree of brainstem displacement measured by the distance between the McRae line and the tip of the GPCirA (∆MT). They evaluated associations between these factors and neurological deficits.
Thirty GPCirAs in 30 patients were included. The prevalence of CNDs was 50%. Patients with CNDs significantly differed from those without CNDs in terms of age (mean 51.0 years [SD 15.0 years] vs 69.0 years [SD 21.0 years], p = 0.01) and in ∆MT (median 50.7 mm [IQR 39.2–53.9 mm] vs 39.0 mm [IQR 32.3–45.9 mm], p = 0.02). The prevalence of motor deficits was 33.3%. Patients with motor deficits showed a larger ∆MT (median 50.5 mm [IQR 40.8–54.6 mm]) compared with those without (∆MT: median 39.1 mm [IQR 32.8–50.5 mm], p = 0.04). GPCirA volume was larger in patients with poor modified Rankin Scale (mRS) scores (median 14.9 cm3 [IQR 8.6–18.7 cm3]) than in those with mRS scores of 0–2 (median 6.8 cm3 [IQR 4.4–11.7 cm3], p = 0.03). After adjusting for patient age and the occurrence of hydrocephalus or PT, the authors found that higher degrees of disability were significantly associated with aneurysm volume (OR 1.13, 95% CI 1.0–1.3; p = 0.04), but not with ∆MT. The occurrence of CND or motor deficit was not associated with any of the examined variables. There was no correlation between GPCirA volume and ∆MT (rs = 0.01, p = 0.96). The prevalence of neurological deficits did not differ between GPCirA at the basilar apex, the basilar trunk, the vertebrobasilar junction, or the vertebral artery.
In this study, the neurological condition of the patients was associated only with GPCirA volume and not with the degree of brainstem displacement, the occurrence of PT or hydrocephalus, or the exact location of the GPCirA. These findings highlight the clinical relevance of GPCirA volume and suggest that factors such as brainstem displacement or PT should play less of a role when finding arguments for or against treatment of GPCirA.
Clinical trial registration no.: NCT02066493 (clinicaltrials.gov)