Nelson M Oyesiku

Emory University, Atlanta, Georgia, United States

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Publications (61)152.88 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: The aim of this study was to compare outcomes of postoperative whole brain radiation therapy (WBRT) to stereotactic radiosurgery (SRS) alone in patients with resected brain metastases (BM). We reviewed records of patients who underwent surgical resection of BM followed by WBRT or SRS alone between 2003 and 2013. Local control (LC) of the treated resected cavity, distant brain control (DBC), leptomeningeal disease (LMD), overall survival (OS), and radiographic leukoencephalopathy rates were estimated by the Kaplan-Meier method. One-hundred thirty-two patients underwent surgical resection for 141 intracranial metastases: 36 (27 %) patients received adjuvant WBRT and 96 (73 %) received SRS alone to the resection cavity. One-year OS (56 vs. 55 %, p = 0.64) and LC (83 vs. 74 %, p = 0.31) were similar between patients receiving WBRT and SRS. After controlling for number of BM, WBRT was associated with higher 1-year DBC compared with SRS (70 vs. 48 %, p = 0.03); single metastasis and WBRT were the only significant predictors for reduced distant brain recurrence in multi-variate analysis. Freedom from LMD was higher with WBRT at 18 months (87 vs. 69 %, p = 0.045), while incidence of radiographic leukoencephalopathy was higher with WBRT at 12 months (47 vs. 7 %, p = 0.001). One-year freedom from WBRT in the SRS alone group was 86 %. Compared with WBRT for patients with resected BM, SRS alone demonstrated similar LC, higher rates of LMD and inferior DBC, after controlling for the number of BM. However, OS was similar between groups. The results of ongoing clinical trials are needed to confirm these findings.
    Journal of Neuro-Oncology 09/2014; · 3.12 Impact Factor
  • Pedram Daraei, Nelson M. Oyesiku, Zara M. Patel
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    ABSTRACT: Background Skull base reconstruction can be accomplished using various donor sites. Vascularized tissue, commonly the nasoseptal flap, is the most effective option for large defects or high flow leaks. In cases where the septum cannot be used, a mucoperiosteal flap from the nasal floor, pedicled from the sphenopalatine artery, is a viable option without reported outcomes. The aim of this work was to describe this flap and to report successful outcomes in a cohort of patients.Methods Retrospective chart review of patients seen by the senior author from 2011 to 2013 requiring skull base reconstruction for defects with cerebrospinal fluid leak.ResultsA total of 108 patients underwent endoscopic skull base reconstruction. Ten patients had reconstruction with use of a pedicled nasal floor flap. Mean age was 53.3 years. Defects involved the ethmoid roof in 5 patients, sellar floor in 2, clivus in 2, and planum sphenoidale in 1. Reasons why the septal flap could not be used were intentional sacrifice due to disease involvement, sacrifice for proper exposure, or previous septal perforation. Mean length of follow-up was 10.2 (range, 4 to 25) months. No patient developed cerebrospinal fluid leaks postoperatively.Conclusion Nasal floor pedicled flaps are an effective alternative to nasoseptal flaps for reconstruction of the skull base, and have not been previously described in the literature. Outcomes are promising in our small cohort of patients. If the septum must be sacrificed, attention should be paid to the nasal floor, which provides a large mucoperiosteal flap that can be consistently exposed and elevated by the experienced surgeon.
    International Forum of Allergy and Rhinology 09/2014; · 1.00 Impact Factor
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    ABSTRACT: Descriptions of the anatomy of the neural communications among the cranial nerves and their branches is lacking in the literature. Knowledge of the possible neural interconnections found among these nerves may prove useful to surgeons who operate in these regions to avoid inadvertent traction or transection. We review the literature regarding the anatomy, function, and clinical implications of the complex neural networks formed by interconnections among the lower cranial and upper cervical nerves. A review of germane anatomic and clinical literature was performed. The review is organized in two parts. Part I concerns the anastomoses between the trigeminal, facial, and vestibulocochlear nerves or their branches with any other nerve trunk or branch in the vicinity. Part II concerns the anastomoses among the glossopharyngeal, vagus, accessory and hypoglossal nerves and their branches or among these nerves and the first four cervical spinal nerves; the contribution of the autonomic nervous system to these neural plexuses is also briefly reviewed. Part I is presented in this article. An extensive anastomotic network exists among the lower cranial nerves. Knowledge of such neural intercommunications is important in diagnosing and treating patients with pathology of the skull base. Clin. Anat. 27:118–130, 2014. © 2013 Wiley Periodicals, Inc.
    Clinical Anatomy 01/2014; 27(1). · 1.16 Impact Factor
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    ABSTRACT: Purpose The purpose of this study was to evaluate intracranial control and patterns of local recurrence (LR) for grade 2 meningiomas treated with intensity modulated radiation therapy (IMRT) with limited total margin expansions of ≤1 cm. Methods and Materials We reviewed records of patients with a neuropathological diagnosis of grade 2 meningioma who underwent IMRT at our institution between 2002 and 2012. Actuarial rates were determined by the Kaplan-Meier method from the end of RT. LR was defined as in-field if ≥90% of the recurrence was within the prescription isodose, out-of-field (marginal) if ≥90% was outside of the prescription isodose, and both if neither criterion was met. Results Between 2002 and 2012, a total of 54 consecutive patients underwent IMRT for grade 2 meningioma. Eight of these patients had total initial margins >1 cm and were excluded, leaving 46 patients for analysis. The median imaging follow-up period was 26.2 months (range, 7-107 months). The median dose for fractionated IMRT was 59.4 Gy (range, 49.2-61.2 Gy). Median clinical target volume (CTV), planning target volume (PTV), and total margin expansion were 0.5 cm, 0.3 cm, and 0.8 cm, respectively. LR occurred in 8 patients (17%), with 2-year and 3-year actuarial local control (LC) of 92% and 74%, respectively. Six of 8 patients (85%) had a known pattern of failure. Five patients (83%) had in-field LR; no patients had marginal LR; and 1 patient (17%) had both. Conclusions The use of IMRT to treat grade 2 meningiomas with total initial margins (CTV + PTV) ≤1 cm did not appear to compromise outcomes or increase marginal failures compared with other modern retrospective series. Of the 46 patients who had margins ≤1 cm, none experienced marginal failure only. These results demonstrate efficacy and low risk of marginal failure after IMRT treatment of grade 2 meningiomas with reduced margins, warranting study within a prospective clinical trial.
    International journal of radiation oncology, biology, physics 01/2014; 88(5):1004–1010. · 4.59 Impact Factor
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    Mohammadali M Shoja, Nelson M Oyesiku
    Clinical Anatomy 01/2014; 27(1):2-3. · 1.16 Impact Factor
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    ABSTRACT: Knowledge of the possible neural interconnections found between the lower cranial and upper cervical nerves may prove useful to surgeons who operate on the skull base and upper neck regions in order to avoid inadvertent traction or transection. We review the literature regarding the anatomy, function, and clinical implications of the complex neural networks formed by interconnections between the lower cranial and upper cervical nerves. A review of germane anatomic and clinical literature was performed. The review is organized into two parts. Part I discusses the anastomoses between the trigeminal, facial, and vestibulocochlear nerves or their branches and other nerve trunks or branches in the vicinity. Part II deals with the anastomoses between the glossopharyngeal, vagus, accessory and hypoglossal nerves and their branches or between these nerves and the first four cervical spinal nerves; the contribution of the autonomic nervous system to these neural plexuses is also briefly reviewed. Part II is presented in this article. Extensive and variable neural anastomoses exist between the lower cranial nerves and between the upper cervical nerves in such a way that these nerves with their extra-axial communications can be collectively considered a plexus. Clin. Anat., 2013. © 2013 Wiley Periodicals, Inc.
    Clinical Anatomy 11/2013; · 1.16 Impact Factor
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    ABSTRACT: Descriptions of the anatomy of the neural communications among the cranial nerves and their branches is lacking in the literature. Knowledge of the possible neural interconnections found among these nerves may prove useful to surgeons who operate in these regions to avoid inadvertent traction or transection. We review the literature regarding the anatomy, function, and clinical implications of the complex neural networks formed by interconnections among the lower cranial and upper cervical nerves. A review of germane anatomic and clinical literature was performed. The review is organized in two parts. Part I concerns the anastomoses between the trigeminal, facial, and vestibulocochlear nerves or their branches with any other nerve trunk or branch in the vicinity. Part II concerns the anastomoses among the glossopharyngeal, vagus, accessory and hypoglossal nerves and their branches or among these nerves and the first four cervical spinal nerves; the contribution of the autonomic nervous system to these neural plexuses is also briefly reviewed. Part I is presented in this article. An extensive anastomotic network exists among the lower cranial nerves. Knowledge of such neural intercommunications is important in diagnosing and treating patients with pathology of the skull base. Clin. Anat., 2013. © 2013 Wiley Periodicals, Inc.
    Clinical Anatomy 11/2013; · 1.16 Impact Factor
  • Neurosurgery 09/2013; · 2.53 Impact Factor
  • Neurosurgery 06/2013; · 2.53 Impact Factor
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    ABSTRACT: BACKGROUND: The endoscopic transsphenoidal approach (eTSA) to lesions of the sellar region is typically performed jointly by neurosurgeons and otolaryngologists. Occasionally, the approach is significantly altered by sinonasal disease, anatomic variants, or previous surgery. However, there are no current guidelines that describe which physical or radiological findings should prompt a change in the plan of care. The purpose of this study was to determine the incidence of sinonasal pathology or anatomic variants noted endoscopically or by imaging that altered preoperative or intraoperative management. METHODS: A retrospective review was performed of 355 consecutive patients who underwent combined neurosurgery-otolaryngology endoscopic sella approach from August 1, 2007 to April 1, 2011. Our practice in these patients involves preoperative otolaryngology clinical evaluation and MRI review. Intraoperative image guidance is not routinely used in uncomplicated eTSA. RESULTS: The most common management alteration was the addition of image guidance based on anatomic variants on MRI, which occurred in 81 patients (35.0%). Eight patients (2.9%) were preoperatively treated with antibiotics and surgery was postponed secondary to acute or chronic purulent rhinosinusitis; two (0.7%) required functional endoscopic sinus surgery for medically refractory disease before eTSA. Five patients (1.8%) required anterior septoplasty intraoperatively for severe nasal septal deviation. Two patients (0.7%) had inverted papilloma and one patient had esthesioneuroblastoma identified preoperatively during rigid nasal endoscopy. CONCLUSION: This is one of the larger reviews of patients undergoing eTSA for sellar lesions and the only study that describes how intraoperative management may be altered by preoperative sinonasal evaluation. We found a significant incidence of sinonasal pathology and anatomic variants that altered routine operative planning; therefore, a thorough sinonasal evaluation is warranted in these cases.
    American Journal of Rhinology and Allergy 05/2013; 27(3):202-205.
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    ABSTRACT: Objective: Pituitary carcinomas are extremely rare tumors associated with poor prognosis despite surgery, radiation and chemotherapy. The hallmark of diagnosis implies subarachnoid, brain, or systemic tumor spread.Methods: We report a case of rapid transformation of atypical non-functioning pituitary adenoma to a carcinoma.Results: A 64-year-old woman presented with sudden onset of ophtalmoplegia. MRI scan showed a pituitary macroadenoma (2.2 × 2.1 cm) with invasion of the right cavernous sinus. Biochemical data was consistent with a non-functioning pituitary adenoma. Pathology showed a pituitary adenoma with negative immunohistochemistry for pituitary hormones. The patient returned a month later with weakness, lethargy, and a dilated non-reactive right pupil. MRI showed an invasive large mass (5 × 4.7 cm). After an emergent second transsphenoidal surgery, histopathologic examination revealed a widely infiltrative neoplasm invading the overlying mucosa and showing a high mitotic activity and necrosis and a very high Ki-67 (MIB-1) proliferation index (80%). MIB-1 retrospectively performed on the first specimen was also elevated (30%.). Soon after the second surgery, MRI showed a 7.9 × 8.0 cm mass that metastasized to dura mater, and extended into the right orbit, right middle cranial fossa, nasopharynx, clivus, posterior fossa, and along the right tentorium cerebelli, resulting in significant compression of the brainstem.Conclusion: Development of a pituitary carcinoma from an adenoma is an exceptional occurrence, and predictors of such course are currently lacking. A very high Ki-67 proliferation index should raise concern of a pituitary carcinoma in situ or premetastatic carcinoma.
    Endocrine Practice 02/2013; · 2.49 Impact Factor
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    ABSTRACT: Since the 19th century, many different approaches to sellar and parasellar pathology have been advocated and mastered by neurosurgeons and otolaryngologists. Today, with significant advances in operative technology, both open and endoscopic approaches to the sella have gained wide acceptance. Here, we discuss our open and endoscopic approaches to sellar and parasellar lesions.
    Operative Techniques in Otolaryngology-Head and Neck Surgery 01/2013; 24(4):208–212.
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    ABSTRACT: Pituitary adenomas are generally considered benign tumors; however, a subset of these tumors displays aggressive behavior and are not easily cured. The protocol for nonsurgical treatment of aggressive pituitary lesions is less standardized than that of other central nervous system tumors. Aggressive surgical treatment, radiation, dopamine agonists, antiangiogenic drugs, and other chemotherapeutics all have roles in the treatment of aggressive pituitary tumors. More studies are needed to improve outcomes for patients with aggressive pituitary tumors.
    Neurosurgery clinics of North America 10/2012; 23(4):587-94. · 1.73 Impact Factor
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    ABSTRACT: : Pituitary tumors and associated neuroendocrine disorders pose significant challenges in diagnostic and therapeutic management. Optimal care of the "pituitary patient" is best provided in a multidisciplinary collaborative environment that includes not only experienced pituitary practitioners in neurosurgery and endocrinology, but also in otorhinolaryngological surgery, radiation oncology, medical oncology, neuro-ophthalmology, diagnostic and interventional neuroradiology, and neuropathology. We provide the background and rationale for recognizing pituitary centers of excellence and suggest a voluntary verification process, similar to that used by the American College of Surgeons for Trauma Center verification. We propose that pituitary centers of excellence should fulfill 3 key missions: (1) provide comprehensive care and support to patients with pituitary disorders; (2) provide residency training, fellowship training, and/or continuing medical education in the management of pituitary and neuroendocrine disease; and (3) contribute to research in pituitary disorders. As this is a preliminary proposal, we recognize several issues that warrant further consideration including center and surgeon practice volume as well as oversight of the verification process. ABBREVIATIONS:: ACGME, Accreditation Council for Graduate Medical EducationACS, American College of SurgeonsCOE, center of excellence.
    Neurosurgery 08/2012; 71(5):916-26. · 2.53 Impact Factor
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    ABSTRACT: To describe the use of radiosurgery (RS) alone to the resection cavity after resection of brain metastases as an alternative to adjuvant whole-brain radiotherapy (WBRT). Sixty-two patients with 64 cavities were treated with linear accelerator-based RS alone to the resection cavity after surgical removal of brain metastases between March 2007 and August 2010. Fifty-two patients (81%) had a gross total resection. Median cavity volume was 8.5 cm(3). Forty-four patients (71%) had a single metastasis. Median marginal and maximum doses were 18 Gy and 20.4 Gy, respectively. Sixty-one cavities (95%) had gross tumor volume to planning target volume expansion of ≥1 mm. Six-month and 1-year actuarial local recurrence rates were 14% and 22%, respectively, with a median follow-up period of 9.7 months. Six-month and 1-year actuarial distant brain recurrence, total intracranial recurrence, and freedom from WBRT rates were 31% and 51%, 41% and 63%, and 91% and 74%, respectively. The symptomatic cavity radiation necrosis rate was 8%, with 2 patients (3%) undergoing surgery. Of the 11 local failures, 8 were in-field, 1 was marginal, and 2 were both (defined as in-field if ≥90% of recurrence within the prescription isodose and marginal if ≥90% outside of the prescription isodose). The high rate of in-field cavity failure suggests that geographic misses with highly conformal RS are not a major contributor to local recurrence. The current dosing regimen derived from Radiation Therapy Oncology Group protocol 90-05 should be optimized in this patient population before any direct comparison with WBRT.
    International journal of radiation oncology, biology, physics 05/2012; 83(1):e61-6. · 4.59 Impact Factor
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    ABSTRACT: Silent corticotroph adenomas (SCAs) are clinically nonfunctioning pituitary adenomas (NFPAs) with positive staining for corticotropin (ACTH) by immunohistochemistry. Whether SCAs behave more aggressively than NFPAs without ACTH immunoreactivity (ACTH negative) remains controversial. To compare characteristics and outcomes of SCAs with ACTH-negative NFPAs and to identify predictors of aggressive outcome. Primary composite endpoint included the first of any of the following events: progression, recurrence, or death. We reviewed all cases of SCAs and all ACTH-negative macroadenomas operated on between April 1995 and December 2007 by 1 neurosurgeon. Our retrospective cohorts included 33 SCAs followed for 42.5 months (median) (range, 6.7-179.0 months) and 126 ACTH-negative patients followed for 42 months (range, 6-142 months). SCA were younger (mean ± SD; 49.6 ± 14.1) than ACTH-negative patients (55.6 ± 12.8, P = .02). Tumor diameter was similar (2.8 ± 1.0 cm); cavernous sinus invasion was present in 45.5% of SCAs and 30.2% of ACTH-negative NFPAs (P = .09). Postoperative tumor residual was detected in 53.1% of SCAs and 49.6% of ACTH-negative patients. Radiation was administered in 40.6% of SCAs at 16 months (range, 3-149 months) and 33.3% of ACTH-negative patients at 13 months (range, 3-94) postoperatively. Progression of residual tumor occurred in 24.2% of SCAs and 11.1% of ACTH-negative patients (P = .08); recurrence was similar (6.0% SCAs vs 5.5% ACTH-negative patients). Cumulative event-free survival rates were not significantly different between the 2 groups (P = .3). Age, sex, tumor size, cavernous sinus invasion, or SCA subtypes were not associated with outcome. SCA patients were younger, but exhibited similar postoperative tumor regrowth rates as ACTH-negative macroadenomas while using a similar adjuvant radiation protocol. Long-term follow-up is warranted because predictors of regrowth are currently lacking.
    Neurosurgery 04/2012; 71(2):296-303; discussion 304. · 2.53 Impact Factor
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    ABSTRACT: Traditionally, endoscopic transsphenoidal pituitary surgery is performed using 2-dimensional (2D) endoscopes, which lack depth of field and contribute to image distortion. Recently, a new generation of 3D endoscopes has been introduced for improved endoscopic depth perception. Little data exist comparing surgical outcomes with 2D vs 3D endoscopic systems. This study examines perioperative and postoperative factors in patients undergoing pituitary surgery using 2D vs 3D endoscopes. The objective of this work was to determine the differences in perioperative and postoperative factors in patients undergoing pituitary surgery using 2D vs 3D endoscopy. Retrospective chart review at a tertiary academic referral center. Statistical comparison was undertaken for perioperative (estimated blood loss, operative time) and postoperative factors (length of stay, complications, and readmission rate). A total of 58 patients underwent endoscopic pituitary surgery during the 24-month study period (22 functional, 36 nonfunctional lesions). The 2D endoscopic system was used for pituitary tumor resection in 32 patients (55%), and the 3D endoscopic system in 26 patients (45%). No significant difference existed between 2D and 3D endoscopic systems for operative time (p = 0.275) or estimated blood loss (p = 0.312). Additionally, no difference was found between groups for cerebrospinal fluid (CSF) leak rate (p = 0.581), postoperative endocrine complications (p = 0.081), length of hospital stay (p = 0.934), or hospital readmission rate (p = 1.0). 3D endoscopy affords the surgeon improved depth of field and stereoscopic vision. Our data demonstrate that 3D endoscopy does not result in significantly different perioperative or postoperative outcomes vs 2D endoscopic surgery.
    International Forum of Allergy and Rhinology 01/2012; 2(1):2-8. · 1.00 Impact Factor
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    Thyroid: official journal of the American Thyroid Association 12/2011; 22(1):101-2. · 2.60 Impact Factor
  • Nelson M Oyesiku, Kalmon D Post
    Neurosurgical FOCUS 07/2011; 31(1):Introduction. · 2.49 Impact Factor
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    ABSTRACT: Nonfunctioning and functioning pituitary tumors can present in numerous ways. They may be difficult to diagnose correctly and, even with proper treatment, may lead to complications. We present the case of a patient who presented with a large, invasive sellar mass and underwent both medical and surgical treatment for this lesion. The patient's course did not progress as was expected from his initial workup. The patient's history, physical examination, laboratory values, pathologic specimens, and radiologic findings are discussed. His management before, during, and after medical therapy and surgery is reviewed by pituitary experts from 2 different institutions. Aspects of diagnosis and management of sellar lesions are presented and reviewed in the literature. Neurosurgeons frequently treat patients with sellar lesions and should remember that despite modern laboratory, pathologic, and radiologic techniques, the diagnosis and treatment of these lesions is not always clear.
    Neurosurgery 03/2011; 68(3):E874-82. · 2.53 Impact Factor

Publication Stats

907 Citations
152.88 Total Impact Points

Institutions

  • 1991–2014
    • Emory University
      • • Department of Neurosurgery
      • • School of Medicine
      • • Department of Ophthalmology
      • • Department of Surgery
      Atlanta, Georgia, United States
  • 2013
    • University of Alabama at Birmingham
      • Department of Cell, Developmental and Integrative Biology (CDIB)
      Birmingham, Alabama, United States