Focal Cerebral Ischemia Model by Endovascular Suture Occlusion of the Middle Cerebral Artery in the Rat

Stroke is the leading cause of disability and the third leading cause of death in adults worldwide1. In human stroke, there exists a highly variable clinical state; in the development of animal models of focal ischemia, however, achieving reproducibility of experimentally induced infarct volume is essential. The rat is a widely used animal model for stroke due to its relatively low animal husbandry costs and to the similarity of its cranial circulation to that of humans2,3. In humans, the middle cerebral artery (MCA) is most commonly affected in stroke syndromes and multiple methods of MCA occlusion (MCAO) have been described to mimic this clinical syndrome in animal models. Because recanalization commonly occurs following an acute stroke in the human, reperfusion after a period of occlusion has been included in many of these models. In this video, we demonstrate the transient endovascular suture MCAO model in the spontaneously hypertensive rat (SHR). A filament with a silicon tip coating is placed intraluminally at the MCA origin for 60 minutes, followed by reperfusion. Note that the optimal occlusion period may vary in other rat strains, such as Wistar or Sprague-Dawley. Several behavioral indicators of stroke in the rat are shown. Focal ischemia is confirmed using T2-weighted magnetic resonance images and by staining brain sections with 2,3,5-triphenyltetrazolium chloride (TTC) 24 hours after MCAO

Spontaneous acute subdural hematoma as an initial presentation of choriocarcinoma: A case report

<p>Abstract</p> <p>Introduction</p> <p>Diverse sequelae of central nervous system metastasis of choriocarcinoma have been reported, including infarction, intra or extra axial hemorrhages, aneurysm formation and carotid-cavernous fistula. Here we report a case of subdural hematoma as the first presentation of choriocarcinoma.</p> <p>Case presentation</p> <p>The patient is a 34-year-old woman whose initial presentation of widely metastatic choriocarcinoma was an acute subdural hematoma, requiring decompressive craniectomy. Histopathologic examination of the tissue showed no evidence of choriocarcinoma, but the patient was found to have diffuse metastatic disease and cerebrospinal fluid indices highly suggestive of intracranial metastasis.</p> <p>Conclusion</p> <p>Choriocarcinoma frequently metastasizes intracranially. We review the diverse possible manifestations of this process. In addition, the cerebrospinal fluid:serum beta-human chorionic gonadotropin ratio is an important factor in diagnosing these cases. Finally, the role of the neurosurgeon is discussed.</p

Penetration of the Optic Nerve by an Internal Carotid Artery-Ophthalmic Artery Aneurysm: Case Report and Literature Review

Abstract OBJECTIVE AND IMPORTANCE Although it is well known that large or giant internal carotid artery-ophthalmic artery aneurysms can cause visual deficits, penetration and schism of the optic nerve by an aneurysm are very rare. CLINICAL PRESENTATION A 48-year-old man presented with an acute onset of right visual deterioration after an episode of severe headache. Magnetic resonance imaging demonstrated penetration of the right optic nerve by an intracranial aneurysm. Cerebral angiography revealed an internal carotid artery-ophthalmic artery aneurysm of 12 × 7 mm. The aneurysm was directed superomedially and appeared to have a “waist” within the penetration. INTERVENTION Intraoperatively, we observed that part of the aneurysm wall was visible through the optic nerve fibers at the junction with the optic chiasm. CONCLUSION Although there was no direct evidence of subarachnoid hemorrhage on imaging scans or with operative exploration, we think that the patient must have experienced sentinel hemorrhaging, leading to visual deterioration. We describe the case in detail and review the world literature

An alternative extradural exposure to the anterior clinoid process: the superior orbital fissure as a surgical corridor

Dolenc has pioneered the extradural approach to the anterior clinoid process (ACP) in approaching the cavernous sinus, clinoidal space, and orbital apex. A key step is the division of the frontotemporal dural fold (FTDF). Less experienced surgeons may not be as versatile in their three-dimensional understanding of the superior orbital fissure and thus may risk injury to its contents. Through our cadaveric and subsequent clinical experience, we have devised a modification of the approach that permits safer handling of the contents of the superior orbital fissure. In five consecutive injected cadaveric heads (10 sides), we performed on one side a traditional extradural exposure of the ACP. On the other side, we performed our alternative dissection. Instead of exposing the ACP from medial to lateral and dividing the frontotemporal dural fold along the assumed path of safety, we followed the edge of the lesser wing from lateral to medial, uncovered the superior orbital fissure, and peeled the outer layer of the cavernous sinus medial to the foramen rotundum along the greater wing, thus uncovering the inferolateral surface of the ACP. This allowed dural division under full visualization. The alternative method proved easier and more reliable in every case. We applied this technical modification in seven patients with no complications. Specifically, there was no injury to the oculomotor, lacrimal, frontal, or trigeminal nerves or branches. We present detailed anatomic expositions of the injected specimens. This technical modification of the extradural approach of Dolenc is a simple, safe, and valuable adjunct to the exposure of the ACP. We recommend its use particularly by relatively inexperienced surgeons

Complications of surgical treatment of arteriovenous malformations

The management of cerebral arteriovenous malformations (AVMs) is one of the most important challenges for neurosurgeons. In this article, the authors discuss the preoperative issues that may lead to complications and intraoperative and postoperative complications of AVM surgery, as well as how to avoid them