Browse

You are looking at 1 - 10 of 15 items for

  • Refine by Access: user x
  • By Author: Recinos, Pablo F. x
  • By Author: Kshettry, Varun R. x
Clear All
Free access

Precious C. Oyem, Erion J. de Andrade, Pranay Soni, Roger Murayi, Derrick Obiri-Yeboah, Diana Lopez, Varun R. Kshettry, and Pablo F. Recinos

OBJECTIVE

The objective of this paper was to describe the volumetric natural history of meningiomas in patients with neurofibromatosis type 2 (NF2).

METHODS

The authors performed a retrospective descriptive study by reviewing NF2 patients with meningiomas at their institution between 2000 and 2019. Demographic data were collected from the electronic medical records. Tumor volume was collected using volumetric segmentation software. Imaging characteristics including peritumoral brain edema (PTBE) and tumor calcification were collected for each patient from their first to most recent MRI at the authors’ institution. An increase of 15% or more per year from original tumor size was used as the cutoff to define growth.

RESULTS

A total of 137 meningiomas from 48 patients were included in the analysis. The average number of tumors per person was 2.9. Ninety-nine (72.3%) tumors were in female patients. The median length of follow-up from first imaging to last imaging was 32 months (IQR 10.9, 68.3 months). Most tumors were located in the cerebral convexity (24.8%), followed by the falcine region (18.2%) and spine (10.2%). The median tumor growth was 0.12 cm3/yr (IQR 0.03, 0.52 cm3/yr). At the time of first imaging, 21.9% of tumors had calcifications, while 13.9% of meningiomas had PTBE. Of 137 tumors, 52 showed growth. Characteristics associated with tumor growth included PTBE (OR 9.12, 95% CI 1.48–56.4), tumor volume (per cm3) at first imaging (OR 0.91, 95% CI 0.83–0.99), and 10-year increased age at first imaging (OR 0.57, 95% CI 0.43–0.74). PTBE had the shortest median time to growth at 9.2 months.

CONCLUSIONS

Although the majority of NF2-associated meningiomas do not grow in the short term, a wide range of growth patterns can be seen. Younger age at first imaging and presence of PTBE are associated with growth. Patients with these characteristics likely benefit from closer follow-up.

Restricted access

Arbaz A. Momin, Pranay Soni, Jianning Shao, Amy S. Nowacki, John H. Suh, Erin S. Murphy, Samuel T. Chao, Lilyana Angelov, Alireza M. Mohammadi, Gene H. Barnett, Pablo F. Recinos, and Varun R. Kshettry

OBJECTIVE

After gross-total resection (GTR) of a newly diagnosed WHO grade II meningioma, the decision to treat with radiation upfront or at initial recurrence remains controversial. A comparison of progression-free survival (PFS) between observation and adjuvant radiation fails to account for the potential success of salvage radiation, and a direct comparison of PFS between adjuvant and salvage radiation is hampered by strong selection bias against salvage radiation cohorts in which only more aggressive, recurrent tumors are included. To account for the limitations of traditional PFS measures, the authors evaluated radiation failure-free survival (RFFS) between two treatment strategies after GTR: adjuvant radiation versus observation with salvage radiation, if necessary.

METHODS

The authors performed a retrospective review of patients who underwent GTR of newly diagnosed WHO grade II meningiomas at their institution between 1996 and 2019. They assessed traditional PFS in patients who underwent adjuvant radiation, postoperative observation, and salvage radiation. For RFFS, treatment failure was defined as time from initial surgery to failure of first radiation. To assess the association between treatment strategy and RFFS while accounting for potential confounders, a multivariable Cox regression analysis adjusted for the propensity score (PS) and inverse probability of treatment weighted (IPTW) Cox regression analysis were performed.

RESULTS

A total of 160 patients underwent GTR and were included in this study. Of the 121 patients who underwent observation, 32 (26.4%) developed recurrence and required salvage radiation. PFS at 3, 5, and 10 years after observation was 75.1%, 65.6%, and 45.5%, respectively. PFS at 3 and 5 years after salvage radiation was 81.7% and 61.3%, respectively. Of 160 patients, 39 received adjuvant radiation, and 3- and 5-year PFS/RFFS rates were 86.1% and 59.2%, respectively. In patients who underwent observation with salvage radiation, if necessary, the 3-, 5-, and 10-year RFFS rates were 97.7%, 90.3%, and 87.9%, respectively. Both PS and IPTW Cox regression models demonstrated that patients who underwent observation with salvage radiation treatment, if necessary, had significantly longer RFFS (PS model: hazard ratio [HR] 0.21, p < 0.01; IPTW model: HR 0.21, p < 0.01).

CONCLUSIONS

In this retrospective, nonrandomized study, adjuvant radiation after GTR of a WHO II meningioma did not add significant benefit over a strategy of observation and salvage radiation at initial recurrence, if necessary, but results must be considered in the context of the limitations of the study design.

Restricted access

Pranay Soni, Jeremy G. Loss, Callan M. Gillespie, Robb W. Colbrunn, Richard Schlenk, Michael P. Steinmetz, Pablo F. Recinos, Edward C. Benzel, and Varun R. Kshettry

OBJECTIVE

The direct lateral approach is an alternative to the transoral or endonasal approaches to ventral epidural lesions at the lower craniocervical junction. In this study, the authors performed, to their knowledge, the first in vitro biomechanical evaluation of the craniovertebral junction after sequential unilateral C1 lateral mass resection. The authors hypothesized that partial resection of the lateral mass would not result in a significant increase in range of motion (ROM) and may not require internal stabilization.

METHODS

The authors performed multidirectional in vitro ROM testing using a robotic spine testing system on 8 fresh cadaveric specimens. We evaluated ROM in 3 primary movements (axial rotation [AR], flexion/extension [FE], and lateral bending [LB]) and 4 coupled movements (AR+E, AR+F, LB + left AR, and LB + right AR). Testing was performed in the intact state, after C1 hemilaminectomy, and after sequential 25%, 50%, 75%, and 100% C1 lateral mass resection.

RESULTS

There were no significant increases in occipital bone (Oc)–C1, C1–2, or Oc–C2 ROM after C1 hemilaminectomy and 25% lateral mass resection. After 50% resection, Oc–C1 AR ROM increased by 54.4% (p = 0.002), Oc LB ROM increased by 47.8% (p = 0.010), and Oc–C1 AR+E ROM increased by 65.8% (p < 0.001). Oc–C2 FE ROM increased by 7.2% (p = 0.016) after 50% resection; 75% and 100% lateral mass resection resulted in further increases in ROM.

CONCLUSIONS

In this cadaveric biomechanical study, the authors found that unilateral C1 hemilaminectomy and 25% resection of the C1 lateral mass did not result in significant biomechanical instability at the occipitocervical junction, and 50% resection led to significant increases in Oc–C2 ROM. This is the first biomechanical study of lateral mass resection, and future studies can serve to validate these findings.

Restricted access

Pranay Soni, Jeremy G. Loss, Callan M. Gillespie, Robb W. Colbrunn, Richard Schlenk, Michael P. Steinmetz, Pablo F. Recinos, Edward C. Benzel, and Varun R. Kshettry

OBJECTIVE

The direct lateral approach is an alternative to the transoral or endonasal approaches to ventral epidural lesions at the lower craniocervical junction. In this study, the authors performed, to their knowledge, the first in vitro biomechanical evaluation of the craniovertebral junction after sequential unilateral C1 lateral mass resection. The authors hypothesized that partial resection of the lateral mass would not result in a significant increase in range of motion (ROM) and may not require internal stabilization.

METHODS

The authors performed multidirectional in vitro ROM testing using a robotic spine testing system on 8 fresh cadaveric specimens. We evaluated ROM in 3 primary movements (axial rotation [AR], flexion/extension [FE], and lateral bending [LB]) and 4 coupled movements (AR+E, AR+F, LB + left AR, and LB + right AR). Testing was performed in the intact state, after C1 hemilaminectomy, and after sequential 25%, 50%, 75%, and 100% C1 lateral mass resection.

RESULTS

There were no significant increases in occipital bone (Oc)–C1, C1–2, or Oc–C2 ROM after C1 hemilaminectomy and 25% lateral mass resection. After 50% resection, Oc–C1 AR ROM increased by 54.4% (p = 0.002), Oc LB ROM increased by 47.8% (p = 0.010), and Oc–C1 AR+E ROM increased by 65.8% (p < 0.001). Oc–C2 FE ROM increased by 7.2% (p = 0.016) after 50% resection; 75% and 100% lateral mass resection resulted in further increases in ROM.

CONCLUSIONS

In this cadaveric biomechanical study, the authors found that unilateral C1 hemilaminectomy and 25% resection of the C1 lateral mass did not result in significant biomechanical instability at the occipitocervical junction, and 50% resection led to significant increases in Oc–C2 ROM. This is the first biomechanical study of lateral mass resection, and future studies can serve to validate these findings.

Free access

Jianning Shao, Jaes Jones, Patrick Ellsworth, Ghaith Habboub, Gino Cioffi, Nirav Patil, Quinn T. Ostrom, Carol Kruchko, Jill S. Barnholtz-Sloan, Varun R. Kshettry, and Pablo F. Recinos

OBJECTIVE

Spinal cord astrocytoma (SCA) is a rare tumor whose epidemiology has not been well defined. The authors utilized the Central Brain Tumor Registry of the United States (CBTRUS) to provide comprehensive up-to-date epidemiological data for this disease.

METHODS

The CBTRUS was queried for SCAs on ICD-O-3 (International Classification of Diseases for Oncology, 3rd edition) histological and topographical codes. The age-adjusted incidence (AAI) per 100,000 persons was calculated and stratified by race, sex, age, and ethnicity. Joinpoint was used to calculate the annual percentage change (APC) in incidence.

RESULTS

Two thousand nine hundred sixty-nine SCAs were diagnosed in the US between 1995 and 2016, resulting in an average of approximately 136 SCAs annually. The overall AAI was 0.047 (95% CI 0.045–0.049), and there was a statistically significant increase from 0.051 in 1995 to 0.043 in 2016. The peak incidence of 0.064 (95% CI 0.060–0.067) was found in the 0- to 19-year age group. The incidence in males was 0.053 (95% CI 0.050–0.055), which was significantly greater than the incidence in females (0.041, 95% CI 0.039–0.044). SCA incidence was significantly lower both in patients of Asian/Pacific Islander race (AAI = 0.034, 95% CI 0.028–0.042, p = 0.00015) and in patients of Hispanic ethnicity (AAI = 0.035, 95% CI 0.031–0.039, p < 0.001). The incidence of WHO grade I SCAs was significantly higher than those of WHO grade II, III, or IV SCAs (p < 0.001).

CONCLUSIONS

The overall AAI of SCA from 1995 to 2016 was 0.047 per 100,000. The incidence peaked early in life for both sexes, reached a nadir between 20 and 34 years of age for males and between 35 and 44 years of age for females, and then slowly increased throughout adulthood, with a greater incidence in males. Pilocytic astrocytomas were the most common SCA in the study cohort. This study presents the most comprehensive epidemiological study of SCA incidence in the US to date.

Free access

Jianning Shao, Jaes Jones, Patrick Ellsworth, Ghaith Habboub, Gino Cioffi, Nirav Patil, Quinn T. Ostrom, Carol Kruchko, Jill S. Barnholtz-Sloan, Varun R. Kshettry, and Pablo F. Recinos

OBJECTIVE

Spinal cord astrocytoma (SCA) is a rare tumor whose epidemiology has not been well defined. The authors utilized the Central Brain Tumor Registry of the United States (CBTRUS) to provide comprehensive up-to-date epidemiological data for this disease.

METHODS

The CBTRUS was queried for SCAs on ICD-O-3 (International Classification of Diseases for Oncology, 3rd edition) histological and topographical codes. The age-adjusted incidence (AAI) per 100,000 persons was calculated and stratified by race, sex, age, and ethnicity. Joinpoint was used to calculate the annual percentage change (APC) in incidence.

RESULTS

Two thousand nine hundred sixty-nine SCAs were diagnosed in the US between 1995 and 2016, resulting in an average of approximately 136 SCAs annually. The overall AAI was 0.047 (95% CI 0.045–0.049), and there was a statistically significant increase from 0.051 in 1995 to 0.043 in 2016. The peak incidence of 0.064 (95% CI 0.060–0.067) was found in the 0- to 19-year age group. The incidence in males was 0.053 (95% CI 0.050–0.055), which was significantly greater than the incidence in females (0.041, 95% CI 0.039–0.044). SCA incidence was significantly lower both in patients of Asian/Pacific Islander race (AAI = 0.034, 95% CI 0.028–0.042, p = 0.00015) and in patients of Hispanic ethnicity (AAI = 0.035, 95% CI 0.031–0.039, p < 0.001). The incidence of WHO grade I SCAs was significantly higher than those of WHO grade II, III, or IV SCAs (p < 0.001).

CONCLUSIONS

The overall AAI of SCA from 1995 to 2016 was 0.047 per 100,000. The incidence peaked early in life for both sexes, reached a nadir between 20 and 34 years of age for males and between 35 and 44 years of age for females, and then slowly increased throughout adulthood, with a greater incidence in males. Pilocytic astrocytomas were the most common SCA in the study cohort. This study presents the most comprehensive epidemiological study of SCA incidence in the US to date.

Open access

Joao Paulo Almeida, Dennis Tang, Varun R. Kshettry, Raj Sindwani, and Pablo F. Recinos

This is the case of a 25-year-old woman who had had a previous rupture of a dermoid cyst and now presented with recent MRI scans suggesting further growth of her dermoid cyst. Her lesion was located in the suprasellar space and extended into the interpeduncular fossa and prepontine cistern. Considering the location of the tumor, an endoscopic pituitary hemitransposition was selected for its resection. In this video we present the technical nuances and illustrate the anatomy used for an endoscopic endonasal pituitary hemitransposition for resection of a suprasellar dermoid cyst with extension into the interpeduncular fossa. In this case, a near-total resection was achieved, with no complications and no additional hormonal deficit after surgery.

The video can be found here: https://youtu.be/BHtNf5invUI.

Open access

Joao Paulo Almeida, Zachary Cappello, Hamid Borghei-Razavi, Pablo F. Recinos, Raj Sindwani, and Varun R. Kshettry

Petroclival chondrosarcomas are a formidable surgical challenge given the close relationship to critical neurovascular structures. The endoscopic endonasal approach can be utilized for many petroclival chondrosarcomas. However, tumors that extend to the inferior petrous apex require working behind the internal carotid artery (ICA). We present a case of a 33-year-old with a 1-year history of complete abducens palsy, with imaging showing an enhancing mass centered at the left petroclival fissure and inferior petrous apex behind the paraclival carotid artery and extending down into the nasopharynx abutting the cervical ICA. In this video, we describe the surgical steps of the endoscopic endonasal translacerum approach with ICA skeletonization and mobilization. We also highlight the relevant surgical anatomy with anatomical dissections to supplement the surgical video. The patient did well without complications. Postoperative MRI demonstrated complete resection and pathology revealed grade II chondrosarcoma. He underwent adjuvant proton beam radiotherapy.

The video can be found here: https://youtu.be/80QXALJW9ME.

Free access

Shahed Tish, Ghaith Habboub, Min Lang, Quinn T. Ostrom, Carol Kruchko, Jill S. Barnholtz-Sloan, Pablo F. Recinos, and Varun R. Kshettry

OBJECTIVE

Spinal schwannoma remains the third most common intradural spinal tumor following spinal meningioma and ependymoma. The available literature is generally limited to single-institution reports rather than epidemiological investigations. As of 1/1/2004, registration of all benign central nervous system tumors in the United States became mandatory after the Benign Brain Tumor Cancer Registries Amendment Act took action, which provided massive resources for United States population-based epidemiological studies. This article describes the epidemiology of spinal schwannoma in the United States from January 1, 2006, through December 31, 2014.

METHODS

In this study, the authors utilized the Central Brain Tumor Registry of the United States, which corresponds to 100% of the American population. The Centers for Disease Control and Prevention’s National Program of Cancer Registries and the National Cancer Institute’s Surveillance Epidemiology and End Results program provide the resource for this data registry. The authors included diagnosis years 2006 to 2014. They used the codes per the International Coding of Diseases for Oncology, 3rd Edition: histology code 9560/0 and site codes C72.0 (spinal cord), C70.1 (spinal meninges), and C72.1 (cauda equina). Rates are per 100,000 persons and are age-adjusted to the 2000 United States standard population. The age-adjusted incidence rates and 95% confidence intervals are calculated by age, sex, race, and ethnicity.

RESULTS

There were 6989 spinal schwannoma cases between the years 2006 and 2014. The yearly incidence eminently increased between 2010 and 2014. Total incidence rate was 0.24 (95% CI 0.23–0.24) per 100,000 persons. The peak adjusted incidence rate was seen in patients who ranged in age from 65 to 74 years. Spinal schwannomas were less common in females than they were in males (incidence rate ratio = 0.85; p < 0.001), and they were less common in blacks than they were in whites (IRR = 0.52; p < 0.001) and American Indians/Alaska Natives (IRR = 0.50; p < 0.001) compared to whites. There was no statistically significant difference in incidence rate between whites and Asian or Pacific Islanders (IRR = 0.92; p = 0.16).

CONCLUSIONS

The authors’ study results demonstrated a steady increase in the incidence of spinal schwannomas between 2010 and 2014. Male sex and the age range 65–74 years were associated with higher incidence rates of spinal schwannomas, whereas black and American Indian/Alaska Native races were associated with lower incidence rates. The present study represents the most thorough assessment of spinal schwannoma epidemiology in the American population.

Free access

Krishna C. Joshi, Alankrita Raghavan, Baha’eddin Muhsen, Jason Hsieh, Hamid Borghei-Razavi, Samuel T. Chao, Gene H. Barnett, John H. Suh, Gennady Neyman, Varun R. Kshettry, Pablo F. Recinos, Alireza M. Mohammadi, and Lilyana Angelov

OBJECTIVE

Gamma Knife radiosurgery (GKRS) has been successfully used for the treatment of intracranial meningiomas given its steep dose gradients and high-dose conformality. However, treatment of skull base meningiomas (SBMs) may pose significant risk to adjacent radiation-sensitive structures such as the cranial nerves. Fractionated GKRS (fGKRS) may decrease this risk, but until recently it has not been practical with traditional pin-based systems. This study reports the authors’ experience in treating SBMs with fGKRS, using a relocatable, noninvasive immobilization system.

METHODS

The authors performed a retrospective review of all patients who underwent fGKRS for SBMs between 2013 and 2018 delivered using the Extend relocatable frame system or the Icon system. Patient demographics, pre- and post-GKRS tumor characteristics, perilesional edema, prior treatment details, and clinical symptoms were evaluated. Volumetric analysis of pre-GKRS, post-GKRS, and subsequent follow-up visits was performed.

RESULTS

Twenty-five patients met inclusion criteria. Nineteen patients were treated with the Icon system, and 6 patients were treated with the Extend system. The mean pre-fGKRS tumor volume was 7.62 cm3 (range 4.57–13.07 cm3). The median margin dose was 25 Gy delivered in 4 (8%) or 5 (92%) fractions. The median follow-up time was 12.4 months (range 4.7–17.4 months). Two patients (9%) experienced new-onset cranial neuropathy at the first follow-up. The mean postoperative tumor volume reduction was 15.9% with 6 patients (27%) experiencing improvement of cranial neuropathy at the first follow-up. Median first follow-up scans were obtained at 3.4 months (range 2.8–4.3 months). Three patients (12%) developed asymptomatic, mild perilesional edema by the first follow-up, which remained stable subsequently.

CONCLUSIONS

fGKRS with relocatable, noninvasive immobilization systems is well tolerated in patients with SBMs and demonstrated satisfactory tumor control as well as limited radiation toxicity. Future prospective studies with long-term follow-up and comparison to single-session GKRS or fractionated stereotactic radiotherapy are necessary to validate these findings and determine the efficacy of this approach in the management of SBMs.