Search Results

You are looking at 1 - 10 of 42 items for

  • Author or Editor: Leonardo Rangel-Castilla x
Clear All Modify Search
Free access

Leonardo Rangel-Castilla and Giuseppe Lanzino

In elderly patients with acute ischemic stroke, tortuosity of the proximal vertebral artery makes access from the transfemoral route challenging and time consuming. In such cases, a transradial approach (TA) offers a more direct vertebral artery (VA) access that overcomes proximal VA tortuosity. In this video the authors illustrate nuances of the TA for acute basilar artery occlusion in two patients with challenging proximal VA anatomy. Techniques, devices, and pitfalls are discussed. In both patients, mechanical clot retrieval was successful and resulted in significant recovery of function. The authors believe that the TA should be the initial approach for basilar artery (BA) occlusion management in elderly patients and should be considered for selected patients with other conditions requiring endovascular treatment.

The video can be found here: https://youtu.be/_Ym9tMKUy_4.

Full access

Leonardo Rangel-Castilla and Robert F. Spetzler

OBJECT

The ideal surgical approach to thalamic cavernous malformations (CMs) varies according to their location within the thalamus. To standardize surgical approaches, the authors have divided the thalamus into 6 different regions and matched them with the corresponding surgical approach.

METHODS

The regions were defined as Region 1 (anteroinferior), Region 2 (medial), Region 3 (lateral), Region 4 (posterosuperior), Region 5 (lateral posteroinferior), and Region 6 (medial posteroinferior). The senior author’s surgical experience with 46 thalamic CMs was reviewed according to this classification. An orbitozygomatic approach was used for Region 1; anterior ipsilateral transcallosal for Region 2; anterior contralateral transcallosal for Region 3; posterior transcallosal for Region 4; parietooccipital transventricularfor Region 5; and supracerebellar-infratentorial for Region 6.

RESULTS

Region 3 was the most common location (17 [37%]). There were 5 CMs in Region 1 (11%), 9 in Region 2 (20%), 17 in Region 3 (37%), 3 in Region 4 (6%), 4 in Region 5 (9%), and 8 in Region 6 (17%). Complete resection was achieved in all patients except for 2, who required a second-stage operation. The mean follow-up period was 1.7 years (range 6 months-9 years). At the last clinical follow-up, 40 patients (87%) had an excellent or good outcome (modified Rankin Scale [mRS] scores 0–2) and 6 (13%) had poor outcome (mRS scores 3–4). Relative to their preoperative condition, 42 patients (91%) were unchanged or improved, and 4 (9%) were worse.

CONCLUSIONS

The authors have presented the largest series reported to date of surgically treated thalamic CMs, achieving excellent results using this methodology. In the authors’ experience, conceptually dividing the thalamus into 6 different regions aids in the selection of the ideal surgical approach fora specific region.

Free access

Gary Rajah, Sandra Narayanan and Leonardo Rangel-Castilla

Flow diversion has become a well-accepted option for the treatment of cerebral aneurysms. Given the significant treatment effect of flow diverters, numerous options have emerged since the initial Pipeline embolization device studies. In this review, the authors describe the available flow diverters, both endoluminal and intrasaccular, addressing nuances of device design and function and presenting data on complications and outcomes, where available. They also discuss possible future directions of flow diversion.

Free access

Leonardo Rangel-Castilla and Robert F. Spetzler

A 70-year-old man with progressive visual disturbances, left superior quadrantanopsia, and right-sided papilledema underwent imaging that demonstrated a right internal carotid artery (ICA) terminus aneurysm with third-ventricle mass effect and ipsilateral optic nerve and chiasm compression. We performed a right modified orbitozygomatic craniotomy, with proximal control and dissection of the aneurysm and small perforator arteries. Temporary ICA and anterior cerebral artery (ACA) clips allowed placement of a large curved permanent clip, reconstructing the ICA bifurcation and maintaining adequate patency of the ACA and middle cerebral artery. Complete aneurysm obliteration was confirmed by intraoperative indocyanine green angiography and postoperative CT angiography.

The video can be found here: http://youtu.be/5WEEgmA-g2A.

Free access

Leonardo Rangel-Castilla and Robert F. Spetzler

We present the case of a 26-year-old female patient who had two episodes of sudden, left, upper and lower extremity paresthesias and weakness, which resolved completely after 5 months. After recovery, she presented for evaluation. Imaging demonstrated a C3-C6 intra- and extra-axial arteriovenous malformation (AVM) with spinal cord compression and edema. A spinal angiogram showed arterial feeders arising from both vertebral arteries and from the right ascending pharyngeal artery. The AVM had been partially embolized after her first bleeding episode. She underwent C3-C6 laminoplasty and microsurgical resection of the AVM. After locating the main arterial feeders and draining veins, the malformation was resected using the pial resection technique. A postoperative spinal angiogram demonstrated gross total resection. Video used with permission from Barrow Neurological Institute.

The video can be found here: http://youtu.be/JbbIwCTUsuI.

Free access

Leonardo Rangel-Castilla, Hussain Shallwani and Adnan H. Siddiqui

Transvenous embolization (TE) has been increasingly applied for arteriovenous malformation (AVM) treatment. Transient cardiac standstill (TCS) has been described in cerebrovascular surgery but is uncommon for endovascular embolization. The authors present a patient with a ruptured thalamic AVM in whom both techniques were applied simultaneously. Surgery was considered, but the patient refused. Transarterial embolization was performed with an incomplete result. The deep-seated draining vein provided sole access to the AVM. A microcatheter was advanced into the draining vein. Under TCS, achieved with rapid ventricular pacing, complete AVM embolization was obtained. One-year magnetic resonance imaging and cerebral angiography demonstrated no residual AVM.

The video can be found here: https://youtu.be/CAzb9md_xBU.

Free access

Lorenzo Rinaldo, Waleed Brinjikji and Leonardo Rangel-Castilla

An 80-year-old female presented with a long history of severe pulsatile tinnitus, vertigo, and decreased hearing. She was found to have a large right-sided tentorial arteriovenous fistula (AVF) with enlarged deep draining veins, including the vein of Rosenthal. The patient underwent Onyx embolization of the fistula via a combined transarterial and transvenous approach resulting in complete obliteration of the fistula. Her symptoms improved immediately after the procedure and at 6-months’ follow-up she was clinically asymptomatic with no evidence of residual fistula on neuroimaging. Transvenous embolization of AVF is at times necessary when transarterial access is not possible.

The video can be found here: https://youtu.be/uOMHY7eaOoQ.

Free access

Salomon Cohen-Cohen, Giuseppe Lanzino and Leonardo Rangel-Castilla

The extended retrosigmoid approach provides an excellent corridor to the lateral aspect of the pontomedullary junction (PMJ).1,2 This video demonstrates a microsurgical resection of a progressive enlarging cavernous malformation (CM) of the PMJ. The patient is a 33-year-old woman with progressive symptoms, including right facial droop, left hemianesthesia, diplopia, and nystagmus. The patient underwent a right extended retrosigmoid approach with intraoperative neuronavigation and neuromonitoring. Lower cranial nerve dissection allowed access to the lateral PMJ. A longitudinal corticotomy was performed above the glossopharyngeal. The CM was removed in a piecemeal fashion. Postoperative MRI confirmed gross-total resection and the patient remained neurologically stable.

The video can be found here: https://youtu.be/K_TtiTo1RsQ.

Free access

Eduardo Martinez-del-Campo, Leonardo Rangel-Castilla, Hector Soriano-Baron and Nicholas Theodore

Object

Performance of MR imaging in patients with gunshot wounds at or near the lumbar spinal canal is controversial. The authors reviewed the literature on the use of MR imaging in gunshot wounds to the spine. They discuss the results from in vitro and clinical studies, analyze the physical properties of common projectiles, and evaluate the safety and indications for MR imaging when metallic fragments are located near the spinal canal.

Methods

A review of the English-language literature was performed. Data from 25 articles were analyzed, including 5 in vitro studies of the interaction between 95 projectiles and the MR system's magnetic fields, and the clinical outcomes in 22 patients with metallic fragments at or near the spinal canal who underwent MR imaging.

Results

Properties of 95 civilian and military projectiles were analyzed at a magnet strength of 1, 1.5, 3, and 7 T. The most common projectiles were bullets with a core of lead, either with a copper jacket or unjacketed (73 [76.8%] of 95). Steel-containing (core or jacket) projectiles comprised 14.7%. No field interaction was evident in 78 (96.3%) of the 81 nonsteel projectiles. All steel projectiles showed at least positive deflection forces, longitudinal migration, or rotation. Heating of the projectiles was clinically insignificant. Image artifact was significant in all 9 steel bullets tested, but was not significant in 39 (88.6%) of the 44 nonsteel bullets tested. Overall, 22 patients with complete (82%) and incomplete (14%) spinal cord injury secondary to a projectile lodged inside the spinal canal underwent MR imaging. Discomfort and further physical or neurological deficits were not reported by any patient. Two patients with spinal cord injuries underwent MR imaging studies before surgical decompression and had subsequent, significant neurological improvement.

Conclusions

Metallic implants near or at the spinal canal are a relative contraindication for MR imaging. However, safe MR imaging might be feasible when a projectile's properties and a patient's individualized clinical presentation are considered.