Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Brandon G. Gaynor is active.

Publication


Featured researches published by Brandon G. Gaynor.


Journal of Neurosurgery | 2014

Incidence of cranial nerve palsy after preoperative embolization of glomus jugulare tumors using Onyx

Brandon G. Gaynor; Mohamed Samy Elhammady; Daniel Jethanamest; Simon I. Angeli; Mohammad Ali Aziz-Sultan

OBJECT The resection of glomus jugulare tumors can be challenging because of their inherent vascularity. Preoperative embolization has been advocated as a means of reducing operative times, blood loss, and surgical complications. However, the incidence of cranial neuropathy associated with the embolization of these tumors has not been established. The authors of this study describe their experience with cranial neuropathy following transarterial embolization of glomus jugulare tumors using ethylene vinyl alcohol (Onyx, eV3 Inc.). METHODS The authors retrospectively reviewed all cases of glomus jugulare tumors that had been treated with preoperative embolization using Onyx at their institution in the period from 2006 to 2012. Patient demographics, clinical presentation, grade and amount of Onyx used, degree of angiographic devascularization, and procedural complications were recorded. RESULTS Over a 6-year period, 11 patients with glomus jugulare tumors underwent preoperative embolization with Onyx. All embolization procedures were completed in one session. The overall mean percent of tumor devascularization was 90.7%. No evidence of nontarget embolization was seen on postembolization angiograms. There were 2 cases (18%) of permanent cranial neuropathy attributed to the embolization procedures (facial nerve paralysis and lower cranial nerve dysfunction). CONCLUSION Embolizing glomus jugulare tumors with Onyx can produce a dramatic reduction in tumor vascularity. However, the intimate anatomical relationship and overlapping blood supply between these tumors and cranial nerves may contribute to a high incidence of cranial neuropathy following Onyx embolization.


Journal of NeuroInterventional Surgery | 2016

Infarct growth despite full reperfusion in endovascular therapy for acute ischemic stroke

Diogo C. Haussen; Raul G. Nogueira; Mohamed Samy Elhammady; Dileep R. Yavagal; Mohammad Ali Aziz-Sultan; Jeremiah Johnson; Brandon G. Gaynor; Shyian Jen; Seena Dehkharghani; Eric C. Peterson

Aim To explore the predictors of infarct core expansion despite full reperfusion after intra-arterial therapy (IAT). Methods We retrospectively reviewed 604 consecutive patients who underwent IAT for anterior circulation large vessel occlusion acute ischemic stroke in two tertiary centers (2008–2013/2010–2013). Sixty patients selected by MRI or CT perfusion presenting within <24 h of onset with modified Thrombolysis In Cerebral Infarction (mTICI) grade 3 or 2c reperfusion were included. Significant infarct growth (SIG) was defined as infarct expansion >11.6 mL. Results Mean age was 67.0±13.7 years, 56% were men. Mean National Institute of Health Stroke Scale (NIHSS) score was 16.2±6.1, time from onset to puncture was 6.8±3.1 h, and procedure length was 1.3±0.6 h. MRI was used for baseline core analysis in 43% of patients. Mean baseline infarct volume was 17.1±19.1 mL, absolute infarct growth was 30.6±74.5 mL, and final infarct volume was 47.7±77.7 mL. Overall, 35% of patients had SIG. Three of 21 patients (14%) treated with stent-retrievers had SIG compared with 14 of 39 (36%) with first-generation devices. Eight of 21 patients (38%) with intravenous tissue plasminogen activator (IV t-PA) had infarct growth compared with 25/39 (64%) without. 23% of patients with SIG had a modified Rankin Scale score ≤2 at 3 months compared with 48% of those without SIG. Multivariate logistic regression indicated that race affected infarct growth. Use of IV t-PA (p=0.03) and stent-retrievers (p=0.03) were independently and inversely correlated with SIG. Conclusions Despite full reperfusion, infarct growth is relatively frequent and may explain poor clinical outcomes in this setting. Ethnicity was found to influence SIG. Use of IV t-PA and stent-retrievers were associated with less infarct core expansion.


Neurosurgery | 2015

Covered Stents for the Prevention and Treatment of Carotid Blowout Syndrome

Brandon G. Gaynor; Diogo C. Haussen; Sudheer Ambekar; Eric C. Peterson; Dileep R. Yavagal; Mohamed Samy Elhammady

BACKGROUND Carotid blowout syndrome (CBS) is a life-threatening emergency resulting from compromise of the carotid artery caused by malignancy in the head and neck. OBJECTIVE To report our experience with covered stents for the prevention or treatment of carotid blowout syndrome secondary to head and neck cancer to ascertain the safety and efficacy of this technique. METHODS We reviewed the characteristics and outcome of all patients who underwent covered stent placement in the extracranial carotid artery in the setting of head and neck malignancy between 2006 and 2013 at the University of Miami. Patient demographics, presenting symptoms, devices used, perioperative complications, imaging, and follow-up data were reviewed. RESULTS Seventeen carotids in 15 patients, whose ages ranged from 20 to 84 years (mean, 70.4 years), were treated with 20 covered nitinol (Viabahn Endoprosthesis, Gore, Flagstaff, Arizona) stents. Three patients were treated acutely for bleeding from carotid blowout, and 12 were treated prophylactically for threatened carotid blowout. All patients were given periprocedural dual antiplatelet therapy. No thromboembolic or ischemic complications were noted. Hemorrhage after treatment occurred in 4 patients. In 2 patients, the hemorrhage was from a source not covered by the stent. CONCLUSION The use of covered stents is a simple, safe, and effective method for treating or preventing carotid blowout syndrome in patients with head and neck malignancy. Carotid artery reconstruction with covered stents may minimize the risk of ischemic complications associated with endovascular or surgical carotid sacrifice.


Skull Base Surgery | 2013

Acellular dermal allograft for sellar repair after transsphenoidal approach to pituitary adenomas.

Brandon G. Gaynor; Ronald J. Benveniste; Seth Lieberman; Roy R. Casiano; Jacques J. Morcos

Objectives Our practice has transitioned from using fat autograft to acellular dermal matrix (AlloDerm, LifeCell Corp, Woodlands, Texas, USA). We present the largest series to our knowledge of AlloDerm for sellar floor repair after transsphenoidal approach to pituitary adenoma and compare rates of postoperative cerebrospinal fluid (CSF) leak with an earlier cohort of patients whose CSF leaks were repaired with fat autograft. Design This is a retrospective cohort study comparing sellar repair with fat autograft versus inlay Alloderm between the years 2003 and 2012. The primary end point was postoperative CSF leak. Results A total of 429 patients (368 primary; 83 revision operations) without intraoperative lumbar drainage were included. A total of 18 postoperative CSF leaks were observed (3.9%). Intraoperative CSF leak occurred in 160 cases (35.5%). Among this subset of patients with intraoperative CSF leak, 95 underwent repair with AlloDerm and 46 underwent repair with fat autograft, with postoperative CSF leak rates of 8.4% and 15.2%, respectively (p = 0.34, chi-square test); 19 patients underwent repair with other techniques or no repair at all, with postoperative leak rate of 0%. Conclusions AlloDerm is an effective alternative to fat autograft in cases of low-flow CSF leak following transsphenoidal resection of pituitary adenoma.


Clinical Neurology and Neurosurgery | 2014

Carotid siphon calcification impact on revascularization and outcome in stroke intervention

Diogo C. Haussen; Brandon G. Gaynor; Jeremiah Johnson; Eric C. Peterson; Mohamed Samy Elhammady; Mohammad Ali Aziz-Sultan; Dileep R. Yavagal

OBJECTIVE The degree of coronary artery calcification has been shown to predict outcomes in coronary artery disease. The impact of intracranial carotid artery calcification on the prognosis of acute ischemic stroke (AIS) is unknown. The authors sought to examine if the degree of intracranial carotid artery calcification influences reperfusion or outcomes in AIS intervention. METHODS All anterior circulation large vessel occlusion AIS cases that underwent intra-arterial therapy from January 2009 to July 2012 were reviewed. Clinical and radiographic data were collected. Non-contrast brain CT scans were assigned a Calcium Extent Score (degree of calcification of the carotid wall circumference), Calcium Thickness Score (thickness of the calcified plaque), and total Carotid Siphon Calcium (CSC) Score (8-point scale). RESULTS One-hundred seventeen patients met inclusion criteria. The mean age was 65.4±15.6 years and 36% were male. Calcification was present in the intracranial carotid artery of 84 patients (71%). Inter-rater agreement for total CSC score was strong (Spearmans rho=0.883, p<0.001). The mean Calcium Extent Score was 1.5±1.3, Calcium Thickness Score 1.3±1.0 and total CSC Score 2.8±2.2. Reperfusion and mRS were not associated with CSC. Multivariate linear regression analysis revealed that older age, history of coronary disease and cervical internal carotid occlusion/near-occlusion were independently associated with higher total CSC scores. CONCLUSION Extensive calcification on the intracranial carotid artery does not have impact on reperfusion or clinical outcomes in AIS patients undergoing endovascular therapy. Higher CSC scores are associated with coronary artery disease, increasing age and cervical internal carotid artery occlusion/near-occlusion.


World Neurosurgery | 2017

Etiology and Treatment Modalities of Occipital Artery Aneurysms

Nauman S. Chaudhry; Brandon G. Gaynor; Shahrose Hussain; Paul D. Dernbach; Mohammad Ali Aziz-Sultan

BACKGROUND Aneurysms of the external carotid artery represent approximately 2% of cervical carotid aneurysms, with the majority being traumatic pseudoaneurysms. Given the paucity of literature available for guidance, the diagnosis, treatment, and follow-up of such lesions are completely individualized. CASE DESCRIPTION We report an 83-year-old woman with an 8-week history of headache in the occipital region, transient episode of gait disturbance, and pulsatile tinnitus on the right. She had no history of trauma, surgery, autoimmune disease, or infection. Physical examination revealed a pulsatile mass tender to palpation in the right occipital scalp. The mass was surgically excised, and histopathological diagnosis of a true aneurysm was made. Postoperatively, the patients symptoms resolved; however, 1 month after the procedure, she developed occipital neuralgia, which was successfully treated with a percutaneous nerve block. CONCLUSIONS To the best of our knowledge, this is the second reported case of a true aneurysm of the occipital artery in a patient with no history of trauma. The clinical examination, diagnosis, and treatment are discussed and the literature is reviewed for previously reported cases.


Asian journal of neurosurgery | 2017

Combined use of intraoperative indocyanine green and dynamic angiography in rotational vertebral artery occlusion

Nauman A Chaudhry; Brandon G. Gaynor; Sudheer Ambekar; Mohamed Samy Elhammady

Rotational vertebral artery occlusion (RVAO) is a well-documented surgically amenable cause of vertebrobasilar insufficiency. Traditionally, patients have been imaged using dynamic rotational angiography. We report a case of RVAO in which intraoperative indocyanine green angiography (ICGA) was used to confirm adequate surgical decompression of the VA. A 57-year-old female who presented with multiple episodes of syncope provoked by turning her head to the right. Rotational dynamic angiography revealed a dominant right VA that became occluded at the level of C5/6 with head rotation to the right. The patient underwent successful surgical decompression of the VA via an anterior cervical approach. ICGA demonstrated VA patency with head rotation. This was further confirmed by intraoperative dynamic catheter angiography. To the best of our knowledge, we present the first use of ICG combined with intra-operative dynamic rotational angiography to document the adequacy surgical decompression of the VA in a patient with RVAO.


Journal of Neurosurgery | 2016

Transischiorectal fossa approach for resection of pudendal nerve schwannoma: case report.

Stephanie Chen; Brandon G. Gaynor; Allan D. Levi

Pudendal nerve schwannomas are very rare, with only two cases reported in the English-language literature. The surgical approaches described in these two case reports are the transgluteal approach and the laparoscopic approach. The authors present the case of a patient with progressive pelvic pain radiating ipsilaterally into her groin, vagina, and rectum, who was subsequently found to have a pudendal schwannoma. The authors used a transischiorectal fossa approach and intraoperative electrophysiological monitoring and successfully excised the tumor. This approach has the advantage of direct access to Alcocks canal with minimal disruption of the pelvic muscles and ligaments. The patient experienced complete relief of her pelvic pain after the procedure.


Skull Base Surgery | 2018

Volumetry in the Assessment of Pituitary Adenoma Resection: Endoscopy versus Microscopy

Anthony C. Wang; Ashish H. Shah; Charif Sidani; Brandon G. Gaynor; Simon Dockrell; S. Shelby Burks; Zoukaa Sargi; Roy R. Casiano; Jacques J. Morcos

Abstract Background Assessment of the extent of resection after surgical resection of pituitary adenomas is most commonly reported in terms of the presence or absence of residual tumor. A quantitative comparison of volumetric resection between endonasal endoscopy (EE) and microsurgery (MS) has rarely been done. Methods A retrospective analysis was performed on a consecutive series of 154 patients with pituitary adenomas treated by the same surgeon at a single institution. We employed volumetric analysis pre‐ and postoperatively on two cohorts of pituitary adenoma patients treated through MS (n = 37) versus EE approach (n = 117). Results Volumetric analysis revealed a higher incidence of complete resection (64.4 vs. 56.8%) and mean volume reduction in the EE cohort (92.7 vs. 88.4%), although not significant. Recurrence rates were significantly lower in the EE group (7.7% vs 24.3%, p = 0.015). Subgroup analysis identified that patients with preoperative tumor volumes >1 mL were less likely to recur through EE (7.8 vs. MS: 29.6%; p = 0.0063). A higher incidence of complete resection was also noted in patients with favorable Knosp grades (0‐1) (EE: 87.8 vs. MS: 63.2%; p = 0.036). Postoperative complication rates were not significantly different between both techniques. Conclusion Both microscopy and endoscopy are well‐tolerated, effective approaches in the treatment of pituitary adenomas. Our series demonstrated that EE may be superior to MS in preventing tumor recurrence and achieving a complete resection in certain subsets of patients. EE provides a slight advantage in tumor control outcomes that may justify the paradigm shift to pure endoscopy at our center.


Journal of Neurosurgery | 2017

Transdural approach to resection of retro-odontoid cysts in elderly patients: report of 3 cases

Karthik Madhavan; Lee Onn Chieng; Brandon G. Gaynor; Allan D. Levi

Retro-odontoid cysts that arise from the tectorial membrane are uncommon lesions that can occur in elderly patients. They arise secondary to degenerative changes, including calcium pyrophosphate deposition within the ligaments. Surgical treatment is indicated when these lesions result in intractable pain, instability, and/or myelopathy. Several surgical techniques to treat this condition exist, but the optimal approach in elderly patients with comorbidities remains controversial. Here, the authors present a case series of 3 patients who underwent successful resection of a retro-odontoid lesion performed through a transdural approach. The patients were 70, 81, and 74 years old and presented with symptoms of cervical myelopathy. In consideration of their advanced age and the location of their lesion, resection via a posterior approach was considered. A 1- to 2-cm suboccipital craniectomy and C-1 and partial C-2 laminectomy were performed. These lesions could not be accessed via an extradural posterolateral approach, and so a transdural approach was performed. In the first 2 patients, a preexisting deformity prompted an instrumented fusion. In the third patient, only a lesion resection was performed. In each case, the dural opening was made using a paramedian ipsilateral-sided incision, and the lesion was resected through an incision in the anterior dura mater. Only the posterior dura was closed primarily. MR imaging evidence of excellent spinal cord decompression was evident in follow-up examinations. Transdural resection of retro-odontoid cysts is a viable option for treating asymmetrical ventral extradural cysts. Results from this case series suggest that such an approach is safe and feasible and can provide an alternative to open or endoscopic anterior transpharyngeal approaches.

Collaboration


Dive into the Brandon G. Gaynor's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge