Allan Friedman

Overview:

At the present time, I am participating in collaborative research in the areas of primary malignant brain tumors, epilepsy and subarachnoid hemorrhage.

Primary malignant brain tumors are increasing in frequency. Patients harboring glioblastoma, the most malignant primary brain tumor, have a life expectancy of less than one year. In colloboration with the Division of Neurology and the Department of Pathology, clinical and laboratory trials have been initiated to identify better treatment for this condition. At present, trials of monoclonal antibodies and novel chemotherapeutic agents are being carried out.

Although physicians have been interested in seizures since the time of Hippocrates, the origin of seizures remains obscure. At Duke University we have treated approximately thirty seizure patients a year by removing abnormal portions of brain. Tissue from these resections is being analyzed for genetics and receptor abnormalities. Positron emission tomography and magnetic resonance imaging are being used to ferret out the origin of the patient's seizures.

Approximately 28,000 patients each year suffer a ruptured intracranial aneurysm. Approximately ten percent of these patients have a genetic predisposition to forming intracranial aneurysms. In conjunction with the Division of Neurology, we are screening candidate genes searching for the cause of intracranial aneurysms.

Positions:

Guy L. Odom Distinguished Professor of Neurosurgery, in the School of Medicine

Neurosurgery
School of Medicine

Professor of Neurosurgery

Neurosurgery
School of Medicine

Interim Chair of Neurosurgery

Neurosurgery
School of Medicine

Member of the Duke Cancer Institute

Duke Cancer Institute
School of Medicine

Education:

M.D. 1974

University of Illinois

Grants:

Novel Targeted Therapeutics for CNS Malignancies

Administered By
Surgery, Surgical Sciences
Awarded By
National Institutes of Health
Role
Collaborating Investigator
Start Date
End Date

Phase II Study of 44Gy from 131I-81C6 for CNS Tumors

Administered By
Neurosurgery, Neuro-Oncology
Awarded By
National Institutes of Health
Role
Co Investigator
Start Date
End Date

GCRC CAP

Administered By
Neurosurgery
Awarded By
National Institutes of Health
Role
Mentor
Start Date
End Date

Therapy of Temodar plus O6-Benzulguanine in Malignant Glioma

Administered By
Neurology, General & Community Neurology
Awarded By
National Institutes of Health
Role
Co Investigator
Start Date
End Date

ZD1839 Therapy of Glioblastoma Multiforme

Administered By
Pediatrics
Awarded By
National Institutes of Health
Role
Collaborator
Start Date
End Date

Publications:

Masson's tumor presenting as a left frontal intraparenchymal hemorrhage resulting in severe expressive aphasia during pregnancy: case report.

Intravascular papillary endothelial hyperplasia (IPEH), commonly known as Masson's tumor, is a benign lesion that manifests as an excessive proliferation of endothelial cells within a vessel wall. IPEH is extremely rare in the brain, with only 36 intracranial cases previously described in the literature. It is commonly mistaken for more malignant pathologies, such as angiosarcoma. Careful histopathological examination is required for diagnosis, as no clinical or radiographic features are characteristic of this lesion. In this first published case of intracranial IPEH presenting during pregnancy, the authors describe a 32-year-old female with a left frontal intraparenchymal hemorrhage resulting in complete expressive aphasia at 28 weeks 6 days' gestation. An MRI scan obtained at a local hospital demonstrated an area of enhancement within the hemorrhage. The patient underwent a left frontoparietal craniotomy for hematoma evacuation and gross-total resection (GTR) of an underlying hemorrhagic mass at 29 weeks' gestation. This case illustrates the importance of multidisciplinary patient care and the feasibility of intervention in the early third trimester with subsequent term delivery. While GTR of IPEH is typically curative, the decision to proceed with surgical treatment of any intracranial lesion in pregnancy must balance maternal stability, gestational age, and suspected pathology.
Authors
Sankey, EW; Hynes, JS; Komisarow, JM; Maule, J; Griffin, AS; Dotters-Katz, SK; Mitchell, CJ; Friedman, AH
MLA Citation
Sankey, Eric W., et al. “Masson's tumor presenting as a left frontal intraparenchymal hemorrhage resulting in severe expressive aphasia during pregnancy: case report.J Neurosurg, Nov. 2019, pp. 1–8. Pubmed, doi:10.3171/2019.8.JNS191767.
URI
https://scholars.duke.edu/individual/pub1417983
PMID
31675720
Source
pubmed
Published In
J Neurosurg
Published Date
Start Page
1
End Page
8
DOI
10.3171/2019.8.JNS191767

Neurosurgical management of petrous bone lesions: classification system and selection of surgical approaches.

BACKGROUND: Surgery of petrous bone lesions (PBLs) is challenging for neurosurgeons. Selection of the surgical approach is an important key for success. In this study, the authors present an anatomical classification for PBLs that has been used by our group for over the past 26 years. The objective of this study is to investigate the benefits and applicability of this classification. METHODS: Between 1994 and 2019, 117 patients treated for PBLs were retrospectively reviewed. Using the V3 and arcuate eminence as reference points, the petrous bone is segmented into 3 parts: petrous apex, rhomboid, and posterior. The pathological diagnoses, selection of the operative approach, and the extent of resection (EOR) were analyzed and correlated using this classification. RESULTS: This series included 22 facial nerve schwannomas (18.8%), 22 cholesterol granulomas (18.8%), 39 chordomas/chondrosarcomas (33.3%), 6 trigeminal schwannomas (5.1%), 13 epidermoids/dermoids (11.1%), and 15 other pathologies (12.8%). PBLs were most often involved with the petrous apex and rhomboid areas (46.2%). The extradural subtemporal approach (ESTA) was most frequently used (57.3%). Gross total resection was achieved in 58.4%. Symptomatic improvement occurred in 92 patients (78.6%). Our results demonstrated a correlation between this classification with each type of pathology (p < .001), selection of surgical approaches (p < 0.001), and EOR (p = 0.008). Chordoma/chondrosarcoma, redo operations, and lesions located medially were less likely to have total resection. Temporary complications occurred in 8 cases (6.8%), persistent morbidity in 5 cases (4.3%), and mortality in 1 case. CONCLUSION: In this study, we proposed a simple classification of PBLs. Using landmarks on the superior petrosal surface, the petrous bone is divided into 3 parts, apex, rhomboid, and posterior. Our results demonstrated that chordoma/chondrosarcoma, redo operations, and lesions involving the tip of the petrous apex or far medial locations were more difficult to achieve total resection. This classification could help surgeons understand surgical anatomy framework, predict possible structures at risk, and select the most appropriate approach for each patient.
Authors
Bawornvaraporn, U; Zomorodi, AR; Friedman, AH; Fukushima, T
MLA Citation
Bawornvaraporn, Udom, et al. “Neurosurgical management of petrous bone lesions: classification system and selection of surgical approaches.Acta Neurochir (Wien), vol. 163, no. 10, Oct. 2021, pp. 2895–907. Pubmed, doi:10.1007/s00701-021-04934-9.
URI
https://scholars.duke.edu/individual/pub1489785
PMID
34313854
Source
pubmed
Published In
Acta Neurochir (Wien)
Volume
163
Published Date
Start Page
2895
End Page
2907
DOI
10.1007/s00701-021-04934-9

Petrous bone lesions: surgical implementation and outcomes of extradural subtemporal approach.

BACKGROUND: Petrous bone lesions (PBLs) are rare with few reports in the neurosurgical literature. In this study, the authors describe our current technique of extradural subtemporal approach (ESTA). The objective of this study was to evaluate the role and efficacy of ESTA for treatment of the PBLs. To our knowledge, this is the largest reported clinical series of using an ESTA-treated PBLs in which the clinical outcomes were evaluated. METHODS: Between 1994 and 2019, 67 patients with PBLs treated by ESTA were retrospectively reviewed. Extent of resection, neurological outcomes, recurrence rate, and surgical complications were evaluated and compared with previous studies. The indications, advantages, limitations, and outcomes of ESTA were analyzed according to pathology. RESULTS: This series included 7 facial nerve schwannomas (10.4%), 16 cholesterol granulomas (23.9%), 16 chordomas (23.9%), 6 chondrosarcomas (9%), 5 trigeminal schwannomas (7.5%), 9 epidermoids/dermoids (13.4%), and 8 other pathologies (11.9%). The most common location of PBLs operated with ESTA was at the petrous apex and rhomboid areas (68.7%). Gross total resection was achieved in 35 (55.6%). Symptomatic improvement occurred in 56 patients (83.6%). Complications occurred in 7 (10.4%) of cases including one mortality. Nine patients (17%) had recurrence within the mean follow-up 71 months. Compared to previous literature, our results demonstrated comparable outcomes but with higher rates of hearing and facial nerve preservation as well as minimal morbidity. From our results, ESTA is an effective therapeutic option for lesions located at the rhomboid and petrous apex, particularly when patients presented with intact facial and hearing function. CONCLUSION: Our series demonstrated that ESTA provided satisfactory outcomes with excellent benefits of hearing and facial function preservation for patients with petrous bone lesions. ESTA should be considered as a safe and effective therapeutic option for selected patients with PBLs.
Authors
Bawornvaraporn, U; Zomorodi, AR; Friedman, AH; Fukushima, T
MLA Citation
Bawornvaraporn, Udom, et al. “Petrous bone lesions: surgical implementation and outcomes of extradural subtemporal approach.Acta Neurochir (Wien), vol. 163, no. 10, Oct. 2021, pp. 2881–94. Pubmed, doi:10.1007/s00701-021-04962-5.
URI
https://scholars.duke.edu/individual/pub1494544
PMID
34420107
Source
pubmed
Published In
Acta Neurochir (Wien)
Volume
163
Published Date
Start Page
2881
End Page
2894
DOI
10.1007/s00701-021-04962-5

How I do it: total resection of a giant sphenoclinoidal meningioma with normalization of near blind vision.

BACKGROUND: Resection of giant sphenoclinoidal meningiomas (SCLM) remains difficult. We discuss a patient presenting with right eye near blindness who underwent total removal of a giant SCLM, resulting in normal vision and no recurrence. METHOD: Utilizing frontotemporal craniotomy, devascularization, debulking, and detachment was achieved. Microdissection of tumor off the optic nerve and carotid perforators was accomplished, resulting in total resection, visual normalization, and no deficits using efficient face-to-face microscope set-up, 2-surgeon 4-hand technique, and double bipolar-suction arrangement. CONCLUSION: Frontotemporal craniotomy was adequate. Preservation of the optic nerve and carotid artery is key. Meticulous microsurgical techniques and refined instruments are important for success.
Authors
Bawornvaraporn, U; Zomorodi, AR; Friedman, AH; Fukushima, T
MLA Citation
Bawornvaraporn, Udom, et al. “How I do it: total resection of a giant sphenoclinoidal meningioma with normalization of near blind vision.Acta Neurochir (Wien), vol. 163, no. 9, Sept. 2021, pp. 2447–52. Pubmed, doi:10.1007/s00701-021-04891-3.
URI
https://scholars.duke.edu/individual/pub1488772
PMID
34247312
Source
pubmed
Published In
Acta Neurochir (Wien)
Volume
163
Published Date
Start Page
2447
End Page
2452
DOI
10.1007/s00701-021-04891-3

Flexible, high-resolution thin-film electrodes for human and animal neural research.

Objective.Brain functions such as perception, motor control, learning, and memory arise from the coordinated activity of neuronal assemblies distributed across multiple brain regions. While major progress has been made in understanding the function of individual neurons, circuit interactions remain poorly understood. A fundamental obstacle to deciphering circuit interactions is the limited availability of research tools to observe and manipulate the activity of large, distributed neuronal populations in humans. Here we describe the development, validation, and dissemination of flexible, high-resolution, thin-film (TF) electrodes for recording neural activity in animals and humans.Approach.We leveraged standard flexible printed-circuit manufacturing processes to build high-resolution TF electrode arrays. We used biocompatible materials to form the substrate (liquid crystal polymer; LCP), metals (Au, PtIr, and Pd), molding (medical-grade silicone), and 3D-printed housing (nylon). We designed a custom, miniaturized, digitizing headstage to reduce the number of cables required to connect to the acquisition system and reduce the distance between the electrodes and the amplifiers. A custom mechanical system enabled the electrodes and headstages to be pre-assembled prior to sterilization, minimizing the setup time required in the operating room. PtIr electrode coatings lowered impedance and enabled stimulation. High-volume, commercial manufacturing enables cost-effective production of LCP-TF electrodes in large quantities.Main Results. Our LCP-TF arrays achieve 25× higher electrode density, 20× higher channel count, and 11× reduced stiffness than conventional clinical electrodes. We validated our LCP-TF electrodes in multiple human intraoperative recording sessions and have disseminated this technology to >10 research groups. Using these arrays, we have observed high-frequency neural activity with sub-millimeter resolution.Significance.Our LCP-TF electrodes will advance human neuroscience research and improve clinical care by enabling broad access to transformative, high-resolution electrode arrays.
Authors
Chiang, C-H; Wang, C; Barth, K; Rahimpour, S; Trumpis, M; Duraivel, S; Rachinskiy, I; Dubey, A; Wingel, KE; Wong, M; Witham, NS; Odell, T; Woods, V; Bent, B; Doyle, W; Friedman, D; Bihler, E; Reiche, CF; Southwell, DG; Haglund, MM; Friedman, AH; Lad, SP; Devore, S; Devinsky, O; Solzbacher, F; Pesaran, B; Cogan, G; Viventi, J
MLA Citation
Chiang, Chia-Han, et al. “Flexible, high-resolution thin-film electrodes for human and animal neural research.J Neural Eng, vol. 18, no. 4, June 2021. Pubmed, doi:10.1088/1741-2552/ac02dc.
URI
https://scholars.duke.edu/individual/pub1482992
PMID
34010815
Source
pubmed
Published In
J Neural Eng
Volume
18
Published Date
DOI
10.1088/1741-2552/ac02dc