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Driscoll, Colin L. W.

A5106135006 | I1330342723

Mayo Clinic

Mayo Clinic

Citations 191

Hydrocephalus in Patients with Vestibular Schwannoma: Institutional Experience with Temporary and Permanent CSF Diversion

Journal of Neurological Surgery Part B: Skull Base | July 13, 2018 | Volume: 79 | Issue: S 01 | Pages: S1-S188

10.1055/s-0038-1633504

Developing “See-through” Vision for Middle Fossa Surgery, A Surgical Anatomy Study

Journal of Neurological Surgery Part B: Skull Base | July 13, 2018 | Volume: 79 | Issue: S 01 | Pages: S1-S188

10.1055/s-0038-1633468

Carotid Artery Injury during Microscopic or Endoscopic Transsphenoidal Surgery

Journal of Neurological Surgery Part B: Skull Base | July 13, 2018 | Volume: 79 | Issue: S 01 | Pages: S1-S188

10.1055/s-0038-1633656

Skull Base Ebstein−Barr—s Virus−Associated Smooth Muscle Tumor in an 8-Year-Old Girl with CD4+ and CD8+ Lymphopenia

Journal of Neurological Surgery Part B: Skull Base | July 13, 2018 | Volume: 79 | Issue: S 01 | Pages: S1-S188

10.1055/s-0038-1633639

Synchronous Epstein-Barr virus–associated skull base and adrenal smooth-muscle tumors in an 8-year-old girl with recent Epstein-Barr virus infection

Journal of Neurosurgery: Pediatrics | June 15, 2018 | Volume: 22 | Issue: 3 | Pages: 283-287

10.3171/2018.3.peds17609 | PMID 29905497

Epstein-Barr virus–associated smooth-muscle tumors are rare tumors seen in immunocompromised patients. Most cases occur in the context of AIDS and organ transplantation, and very rarely in the setting of congenital immunodeficiency, with only 5 case reports of the latter published so far in the literature. The authors report the case of a previously healthy 8-year-old girl with headaches and precocious puberty who was found to have a large skull base lesion. There was a synchronous left adrenal lesion. She underwent resection of the skull base lesion and a left adrenalectomy. Thorough evaluation for immunodeficiency was negative for a known congenital immunodeficiency syndrome. She had a short course of intravenous immunoglobulin and has had no recurrence of disease or new lesions in the 17 months since presentation. Continued surveillance for the development of opportunistic infections and new or recurrent lesions is warranted in this case. Repeat surgery for surgically accessible tumors or chemoradiation would be recommended for any additional lesions.
Natural History of Sporadic Vestibular Schwannoma: A Volumetric Study of Tumor Growth

Otolaryngology–Head and Neck Surgery | April 24, 2018 | Volume: 159 | Issue: 3 | Pages: 535-542

10.1177/0194599818770413 | PMID 29685084

Objective(1) Assess 3‐dimensional volumetric growth of untreated sporadic vestibular schwannomas (VSs) in a large cohort of patients treated with conservative observation. (2) Compare volumetric and conventional linear diameter measurements for detecting tumor growth.Study DesignCase series with chart review.SettingTertiary skull base referral center.Subjects and MethodsPatients with sporadic VS who elected initial conservative treatment with at least 2 serial magnetic resonance imaging (MRI) scans were included. Tumor volume was determined with 3‐dimensional segmentation of MRI sequences. The volumetric threshold for tumor growth was an increase ≥20% from baseline tumor volume. Tumor size based on linear diameter was assessed with the 1995 American Academy of Otolaryngology—Head and Neck Surgery Foundation guidelines for VS outcome reporting, with growth defined as an increase ≥2 mm.ResultsA total of 361 patients were included with a median radiologic follow‐up of 4.1 years (interquartile range [IQR], 2.5‐6.8). At diagnosis, 232 VSs (64%) were purely intracanalicular, and 129 (36%) extended into the cerebellopontine angle. The median baseline tumor volume was 0.161 cm3 (IQR, 0.054‐0.418). Overall, 69% of tumors demonstrated volumetric growth at a median of 1.1 years (IQR, 0.6‐2.1) after initial MRI. In contrast, based on linear measurement assessment, 48% of tumors demonstrated growth at a median of 1.8 years (IQR, 0.8‐3.1) from first MRI scan. Disequilibrium, facial hypoesthesia, aural fullness, initial tumor size, and nonincidental diagnosis were associated with tumor growth.ConclusionThree‐dimensional volumetric assessment of VS provides a more sensitive measure of tumor growth when compared with linear diameter assessment. Through volumetric analysis, the current study revealed that a significant proportion of VSs demonstrate growth during observation.
Long-term tumor control following stereotactic radiosurgery for jugular paraganglioma using 3D volumetric segmentation

Journal of Neurosurgery | April 13, 2018 | Volume: No volume available | Issue: No issue available | Pages: 1-9

10.3171/2017.10.jns17764 | PMID 29652232

OBJECTIVE The morbidity of gross-total resection of jugular paraganglioma (JP) is often unacceptable due to the potential for irreversible lower cranial neuropathy. Stereotactic radiosurgery (SRS) has been used at the authors’ institution since 1990 for the treatment of JP and other benign intracranial tumors. Conventional means of assessing tumor progression using linear measurements or elliptical approximations are imprecise due to the irregular shape and insinuating growth pattern of JP. The objective of this study was to assess long-term tumor control in these patients by using slice-by-slice 3D volumetric segmentation of serial MRI data. METHODS Radiographic data and clinical records were reviewed retrospectively at a single, tertiary-care academic referral center for patients treated from 1990 to 2017. Volumetric analyses by integration of consecutive tumor cross-sectional areas (tumor segmentation) of serial MRI data were performed. Tumor progression was defined as volumetric growth of 15% or greater over the imaging interval. Primary outcomes analyzed included survival free of radiographic and clinical progression. Secondary outcomes included new or worsened cranial neuropathy. RESULTS A total of 85 patients were treated with Gamma Knife radiosurgery (GKRS) for JP at the authors’ institution over the last 27 years. Sixty patients had pretreatment and serial posttreatment contrast-enhanced MRI follow-up suitable for volumetric analysis. A total of 214 MR images were analyzed to segment tumor images in a slice-by-slice fashion to calculate integral tumor volume. The median follow-up duration was 66 months (range 7–202 months). At 5 years the tumor progression-free survival rate was 98%. Three tumors exhibited progression more than 10 years after GKRS. Estimated survival free of radiographic progression rates (95% confidence interval [CI]; n = number still at risk) at 5, 10, and 15 years following radiosurgery were 98% (95% CI 94%–100%; n = 34), 94% (95% CI 85%–100%; n = 16), and 74% (95% CI 56%–98%; n = 6), respectively. One patient with tumor progression required treatment intervention using external beam radiation therapy, constituting the only case of clinical progression. Two patients (3%) without preexisting lower cranial nerve dysfunction developed new ipsilateral vocal fold paralysis following radiosurgery. CONCLUSIONS SRS achieves excellent long-term tumor control for JP without a high risk for new or worsened cranial neuropathy when used in primary, combined modality, or recurrent settings. Long-term follow-up is critical due to the potential for late radiographic progression (i.e., more than 10 years after SRS). As none of the patients with late progression have required salvage therapy, the clinical implications of this degree of tumor growth have yet to be determined.
Macrophage Density Predicts Facial Nerve Outcome and Tumor Growth after Subtotal Resection of Vestibular Schwannoma

Journal of Neurological Surgery Part B: Skull Base | February 7, 2018 | Volume: 79 | Issue: 05 | Pages: 482-488

10.1055/s-0038-1627474 | PMID 30210976

Introduction Vestibular schwannoma (VS) behavior following subtotal resection (STR) is highly variable. Overall progression rates have been reported as high as 44%, and optimal treatment is controversial. Correspondingly, identification of a reliable clinical or pathologic marker associated with progression after STR would help guide decision-making. Methods A prospectively maintained institutional VS registry from 1999 to 2014 was retrospectively reviewed for sporadic VS patients who underwent primary STR without preceding stereotactic radiosurgery (SRS) by a single neurosurgery-neurotology team. Primary endpoints included tumor progression and postoperative facial nerve function. Pathologic specimens were stained for Ki67, CD68, S100, and SOX10 and were quantitated by digital imaging analysis. Macrophage density was defined as the ratio of CD68+ macrophages to S100+ macrophages and Schwannian tumor cells. Clinical outcomes were correlated with pathologic markers. Results Forty-six patients met the study inclusion criteria. Thirteen (28%) progressed during a mean 57 months of follow-up (range 15–149). Favorable postoperative facial nerve function (House–Brackmann I–II) was achieved in 37 (80%). CD68+ cells were present at significantly higher concentrations in tumors that progressed (p = 0.03). Higher macrophage density was significantly associated with both tumor progression (p = 0.02) and unfavorable facial nerve function (p = 0.02). Ki67 percent positivity was not significantly associated with either primary endpoint (p = 0.83; p = 0.58). Conclusions Macrophage density may provide an important marker for individuals at the highest risk for progression of VS after STR, potentially prompting closer surveillance or consideration for upfront SRS following STR. This finding supports preceding conclusions that an intratumoral macrophage-predominant inflammatory response may be a marker for tumor growth and a potential therapeutic target.
Labyrinthine Sequestrum: A Case Report and Review of the Literature

Otology & Neurotology | January 16, 2018 | Volume: 39 | Issue: 3 | Pages: 340-343

10.1097/mao.0000000000001676 | PMID 29337715

Objective: To report the presentation, diagnosis, management, and convalescence of labyrinthine sequestrum (LS) and summarize all previously published cases. Patient(s): Eleven-year-old female with LS. Intervention(s): Multidisciplinary diagnostic evaluation and treatment. Main Outcome Measures: Imaging and laboratory findings, medical and surgical treatment. Results: We describe a case of LS secondary to medically recalcitrant suppurative otitis media in an 11-year-old female and review all eight previously reported cases. The index patient presented after 6 months of otitis media, profound unilateral hearing loss, with symptoms suggesting meningitis. Temporal bone CT demonstrated marked bony destruction of the left otic capsule. Gadolinium-enhanced MRI showed an enhancing process with evidence of meningitis and subdural empyema. The patient was treated with surgical debridement and culture directed antibiotic therapy. Posttreatment imaging showed resolution of intracranial infection with fibrous bony healing of the otic capsule resembling fibrous dysplasia. Conclusion: LS is a rare form of labyrinthitis characterized by centrifugal destruction of the otic capsule. The current index case highlights the importance of combined medical and surgical treatment and describes for the first time in the literature the fibrous ossification of the otic capsule following disease resolution.
Hearing Outcomes After Stereotactic Radiosurgery for Jugular Paraganglioma

Otology & Neurotology | November 30, 2017 | Volume: 39 | Issue: 1 | Pages: 99-105

10.1097/mao.0000000000001636 | PMID 29194225

Objective: To describe audiometric outcomes following stereotactic radiosurgery (SRS) for jugular paraganglioma (JP). Study Design: Retrospective review. Setting: Tertiary referral center. Patients: Patients with pretreatment serviceable hearing (American Academy of Otolaryngology—Head and Neck Surgery [AAO-HNS] Class A or B) and serial post-SRS audiometric follow-up who underwent Gamma Knife SRS for JP between 1990 and 2017. Intervention(s): Gamma Knife SRS. Main Outcome Measures: Progression to nonserviceable hearing; correlation between baseline hearing and treatment parameters with audiometric outcomes. Results: Of 85 patients with JP who underwent SRS during the study period, 35 (66% female, median age 53) had pretreatment serviceable hearing and serial post-treatment audiometry available for review. Median tumor volume at the time of treatment was 7,080 mm3, median cochlear point dose was 5.8 Gy (interquartile range [IQR] 4.1 to 7.3 Gy), and median marginal and maximum tumor doses were 16 and 32 Gy, respectively. After a median follow-up of 37 months (IQR 16 to 77 mo), the median change in pure-tone average and speech discrimination score in the treated ear was −1.2 dB HL/yr (IQR −4.5 to 0.3) and 0%/yr (IQR 0–3.5%), compared with 0.07 dB HL/yr (IQR −0.03 to 0.12) and 0 %/yr (IQR 0 to 0%) in the contralateral untreated ear. Seven patients developed nonserviceable hearing (AAO-HNS Class C or D) at a median of 13.2 months following SRS (IQR 4.8 to 24 mo). Among those who maintained serviceable hearing, median audiometric follow-up was 42 months (IQR 18 to 77 mo). The Kaplan–Meier estimated rates of serviceable hearing at 1, 3, and 5 years following SRS were 91%, 80%, and 80%, respectively. Sixty percent of patients with pulsatile tinnitus who underwent SRS experienced varying levels of symptomatic improvement following treatment. Conclusion: The short- and intermediate-term risk of progression to nonserviceable hearing following SRS for JP is low. Data regarding the impact of cochlear dose from the vestibular schwannoma literature should not be freely applied to JP, since the impact of SRS parameters on hearing preservation seems to be less significant.