scholarly journals Stereotactic radiosurgery for intradural spine tumors using cone-beam CT image guidance

2017 ◽  
Vol 42 (1) ◽  
pp. E11 ◽  
Author(s):  
Andrés Monserrate ◽  
Benjamin Zussman ◽  
Alp Ozpinar ◽  
Ajay Niranjan ◽  
John C. Flickinger ◽  
...  
Keyword(s):  
Image Guidance ◽  
Cone Beam Ct ◽  
Cone Beam ◽  
Spine Tumors ◽  
Alternative Treatment Option ◽  
Cbct Image ◽  
Spine Radiosurgery ◽  
Prescription Dose ◽  
The Mean ◽  
Patient Setup

OBJECTIVE Cone-beam CT (CBCT) image guidance technology has been widely adopted for spine radiosurgery delivery. There is relatively little experience with spine radiosurgery for intradural tumors using CBCT image guidance. This study prospectively evaluated a series of intradural spine tumors treated with radiosurgery. Patient setup accuracy for spine radiosurgery delivery using CBCT image guidance for intradural spine tumors was determined. METHODS Eighty-two patients with intradural tumors were treated and prospectively evaluated. The positioning deviations of the spine radiosurgery treatments in patients were recorded. Radiosurgery was delivered using a linear accelerator with a beam modulator and CBCT image guidance combined with a robotic couch that allows positioning correction in 3 translational and 3 rotational directions. To measure patient movement, 3 quality assurance CBCTs were performed and recorded in 30 patients: before, halfway, and after the radiosurgery treatment. The positioning data and fused images of planning CT and CBCT from the treatments were analyzed to determine intrafraction patient movements. From each of 3 CBCTs, 3 translational and 3 rotational coordinates were obtained. RESULTS The radiosurgery procedure was successfully completed for all patients. Lesion locations included cervical (22), thoracic (17), lumbar (38), and sacral (5). Tumor histologies included schwannoma (27), neurofibromas (18), meningioma (16), hemangioblastoma (8), and ependymoma (5). The mean prescription dose was 17 Gy (range 12–27 Gy) delivered in 1–3 fractions. At the halfway point of the radiation, the translational variations and standard deviations were 0.4 ± 0.5, 0.5 ± 0.8, and 0.4 ± 0.5 mm in the lateral (x), longitudinal (y), and anteroposterior (z) directions, respectively. Similarly, the variations immediately after treatment were 0.5 ± 0.4, 0.5 ± 0.6, and 0.6 ± 0.5 mm along x, y, and z directions, respectively. The mean rotational angles were 0.3° ± 0.4°, 0.3° ± 0.4°, and 0.3° ± 0.4° along yaw, roll, and pitch, respectively, at the halfway point and 0.5° ± 0.5°, 0.4° ± 0.5°, and 0.2° ± 0.3° immediately after treatment. CONCLUSIONS Radiosurgery offers an alternative treatment option for intradural spine tumors in patients who may not be optimal candidates for open surgery. CBCT image guidance for patient setup for spine radiosurgery is accurate and successful in patients with intradural tumors.

scholarly journals Radiosurgery for benign tumors of the spine using the Synergy S with cone-beam computed tomography image guidance

2012 ◽  
Vol 117 (Special_Suppl) ◽  
pp. 197-202 ◽  
Author(s):  
Peter C. Gerszten ◽  
Stephanie Chen ◽  
Mubina Quader ◽  
Yuanguang Xu ◽  
Josef Novotny ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Spinal Cord ◽  
Cone Beam Computed Tomography ◽  
Image Guidance ◽  
Cauda Equina ◽  
Cone Beam ◽  
Maximum Point ◽  
Spine Tumors ◽  
Cbct Image ◽  
The Mean

Object There is a growing body of evidence to support the safe and effective use of spine radiosurgery. However, there is much less experience regarding the use of radiosurgery for the treatment of benign as opposed to malignant spine tumors. This study represents an evaluation of, and reporting on, the technical aspects of using a dedicated radiosurgery system for the treatment of benign spine tumors. Methods Forty-five consecutive benign spine tumors were treated using the Elekta Synergy S 6-MV linear accelerator with a beam modulator and cone-beam computed tomography (CBCT) image guidance technology for target localization. The study cohort included 16 men and 29 women, ranging in age from 23 to 88 years (mean age 52 years). There were 14 cervical, 12 thoracic, 14 lumbar, and 5 sacral tumors. Forty-one lesions (91%) were intradural. The most common histological types of tumor were schwannoma, neurofibroma, and meningioma. Indications for radiosurgery included primary treatment in 24 cases (53%) and treatment of recurrent or residual tumor after open resection in 21 cases (47%). Results No subacute or long-term spinal cord or cauda equina toxicity occurred during the follow-up period (median 32 months). The mean maximum dose received by the gross tumor volume (GTV) was 16 Gy (range 12–24 Gy) delivered in a single fraction in 39 cases. The mean lowest dose received to the GTV was 12 Gy (range 8–16 Gy). The GTV ranged from 0.37 to 94.5 cm3 (mean 13.7 cm3, median 5.9 cm3). In the majority of cases, a planning target volume expansion of 2 mm was employed (38 cases; 84%). The mean maximum point dose delivered to the spinal cord was 8.7 Gy (range 4–11.5 Gy); the mean volume of the spinal cord that received greater than 8 Gy was 0.9 cm3 (range 0.0–5.1 cm3); and the mean dose delivered to 0.1 cm3 of the spinal cord was 7.5 Gy (range 3–10.5 Gy). The mean maximum point dose delivered to the cauda equina was 10 Gy (range 0–13 Gy); the mean volume of the cauda equina that received greater than 8 Gy was 1.45 cm3 (range 0.0–10.6 cm3); and the mean dose delivered to 0.1 cm3 of the cauda equina was 8 Gy (range 0.5–11 Gy). Conclusions In this study the authors describe the contouring and prescribed dose techniques used in the treatment planning and delivery of radiosurgery for benign neoplasms of the spine using CBCT image guidance. This technique may serve as an important reference for the performance of radiosurgery when one believes it is clinically indicated as a treatment modality for a benign spine tumor that is associated with both a high safety profile and a strong positive clinical outcome.

Setup accuracy of spine radiosurgery using cone beam computed tomography image guidance in patients with spinal implants

2010 ◽  
Vol 12 (4) ◽  
pp. 413-420 ◽  
Author(s):  
Peter C. Gerszten ◽  
Edward A. Monaco ◽  
Mubina Quader ◽  
Josef Novotny ◽  
Jong Oh Kim ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Cone Beam Computed Tomography ◽  
Image Guidance ◽  
Spinal Instrumentation ◽  
Target Volume ◽  
Cone Beam ◽  
Spinal Implants ◽  
Cbct Image ◽  
Spine Radiosurgery ◽  
Patient Setup

Object Cone beam computed tomography (CBCT) image guidance technology has been adopted for use in spine radiosurgery. There is concern regarding the ability to safely and accurately perform spine radiosurgery without the use of implanted fiducials for image guidance in postsurgical cases in which titanium instrumentation and/or methylmethacrylate (MMA) has been implanted. In this study the authors prospectively evaluated the accuracy of the patient setup for spine radiosurgery by using CBCT image guidance in the context of orthopedic hardware at the site of disease. Methods The positioning deviations of 31 single-fraction spine radiosurgery treatments in patients with spinal implants were prospectively evaluated using the Elekta Synergy S 6-MV linear accelerator with a beam modulator and CBCT image guidance combined with a robotic couch that allows positioning correction in 3 translational and 3 rotational directions. To measure patient movement, 3 quality-assurance CBCT studies were performed and recorded: before, halfway through, and after radiosurgical treatment. The positioning data and fused images of planning CTs and CBCTs from the treatments were analyzed to determine intrafractional patient movements. From each of 3 CBCTs, 3 translational and 3 rotational coordinates were obtained. Results The prescribed dose to the gross tumor volume for the cohort was 12–18 Gy (mean 14 Gy) utilizing 9–14 coplanar intensity-modulated radiation therapy (IMRT) beams (mean 10 beams). At the halfway point of the radiosurgery, the translational variations and standard deviations were 0.6 ± 0.6, 0.4 ± 0.4, and 0.5 ± 0.5 mm in the lateral (X), longitudinal (Y), and anteroposterior (Z) directions, respectively. The magnitude of the 3D vector (X,Y,Z) was 1.1 ± 0.7 mm. Similarly, the variations immediately after treatment were 0.5 ± 0.3, 0.4 ± 0.4, and 0.5 ± 0.6 mm along the X, Y, and Z directions, respectively. The 3D vector was 1.0 ± 0.6 mm. The mean rotational angles were 0.3 ± 0.4, 0.5 ± 0.6, and 0.3 ± 0.4° along yaw, roll, and pitch, respectively, at the halfway point and 0.3 ± 0.4, 0.6 ± 0.6, and 0.4 ± 0.5° immediately after treatment. Conclusions Cone beam CT image guidance used for patient setup for spine radiosurgery was highly accurate despite the presence of spinal instrumentation and/or MMA at the level of the target volume. The presence of such spinal implants does not preclude safe treatment via spine radiosurgery in these patients.

Prospective evaluation of a dedicated spine radiosurgery program using the Elekta Synergy S system

2010 ◽  
Vol 113 (Special_Supplement) ◽  
pp. 236-241 ◽  
Author(s):  
Peter C. Gerszten ◽  
Josef Novotny ◽  
Mubina Quader ◽  
Valerie C. Dewald ◽  
John C. Flickinger
Keyword(s):  
Quality Assurance ◽  
Image Guidance ◽  
Treatment Time ◽  
Cone Beam Ct ◽  
Patient Positioning ◽  
Quality Assurance Program ◽  
Benign Tumors ◽  
Single Fraction ◽  
Cbct Image ◽  
Spine Radiosurgery

Object Cone beam CT (CBCT) image guidance has recently been adopted for the delivery of spine radiosurgery. In 2007, the authors' institution began a dedicated spine radiosurgery program using the Elekta Synergy S system, which incorporates CBCT technology. In this study, the authors prospectively evaluated the Synergy S platform as a dedicated spine radiosurgery delivery system, including an evaluation of the accuracy of patient positioning using this technology, as part of a quality assurance program. Methods One hundred sixty-six spine and paraspinal lesions were treated using the Elekta Synergy S 6-MV LINAC with a beam modulator and CBCT image guidance combined with a HexaPOD couch that allows correction of patient positioning in 3 translational and 3 rotational directions. Stratifying the lesion by location, there were 28 cervical, 69 thoracic, 48 lumbar, and 21 sacral lesions. The most common histological types for the metastatic lesions (136 cases total) were breast, lung, sarcomas, and renal cells. The most common benign tumors (30 cases total) included 10 schwannomas, 5 neurofibromas, and 5 meningiomas. Twenty-eight lesions (17%) were intradural. To measure intratreatment patient movement, 3 quality assurance CBCTs were performed and recorded at separate times: immediately before treatment started; at the first third of the procedure; and at the second third of the procedure. The positioning data and fused images of the planning CT and CBCT were analyzed to determine intrafraction patient movements. From each of 3 quality assurance CBCT images, 3 translational and 3 rotational coordinates were obtained. Results The prescribed dose to the gross tumor volume, delivered in a single fraction, ranged from 12 to 20 Gy (mean 16 Gy) in this cohort. This dose was delivered by between 7 and 14 coplanar intensity-modulated radiation therapy beams (mean 9 beams). The gross tumor volumes ranged from 1.2 to 491.7 cm3 (mean 39.2 cm3). Mean treatment time including setup was 64 minutes. At the first third of the treatment, the magnitude of the 3D translational vector (X, Y, Z) was 1.1 ± 0.7 mm. Similarly, the 3D translational vector at the second third of the treatment was 1.0 ± 0.6 mm. The means ± SDs of the rotational angles were 0.2° ± 0.4°, 0.4° ± 0.5°, and 0.3° ± 0.5° along yaw, roll, and pitch, respectively, at the first third of the treatment, and 0.2° ± 0.3°, 0.4° ± 0.5°, and 0.4° ± 0.5°, respectively, at the second third of the treatment. Conclusions Single-fraction spine radiosurgery performed using the Synergy S platform and incorporating CBCT image guidance was determined to be feasible, accurate, and safe. This technique provides an overall translational position accuracy of < 2.0 mm.

Improved image quality of cone beam CT scans for radiotherapy image guidance using fiber-interspaced antiscatter grid

2014 ◽  
Vol 41 (6Part1) ◽  
pp. 061910 ◽  
Author(s):  
Uros Stankovic ◽  
Marcel van Herk ◽  
Lennert S. Ploeger ◽  
Jan-Jakob Sonke
Keyword(s):  
Image Quality ◽  
Image Guidance ◽  
Cone Beam Ct ◽  
Ct Scans ◽  
Cone Beam ◽  
Antiscatter Grid

scholarly journals Measurement of pharyngeal segments in Obstructive Sleep Apnea

2018 ◽  
Vol 21 (1) ◽  
pp. 64
Author(s):  
Marcos Marques Rodrigues ◽  
Lucas Borin Moura ◽  
Ariane De Souza Oliveira ◽  
Marisa Aparecida Cabrini Gabrielli ◽  
Valfrido Antonio Pereira Filho ◽  
...  
Keyword(s):  
Obstructive Sleep Apnea ◽  
Sleep Apnea ◽  
Cone Beam Ct ◽  
Sleep Apnea Syndrome ◽  
Upper Airway ◽  
Cone Beam ◽  
Obstructive Sleep ◽  
Intimate Relation ◽  
The Mean ◽  
Cephalometric Measurements

<p><strong>Objective</strong>: Obstructive Sleep Apnea (OSA) occurs by recurrent collapse of the upper airway during sleep. It results in complete (apnea) or partial (hypopnea) reduction of airflow and has intimate relation with the upper airway anatomy. Cephalometric analysis has been used to quantify airway dimensions. The aim of this study is evaluate the correlation between the anteroposterior dimension of the upper airway and the severity of obstructive sleep apnea. <strong>Material and Methods</strong>: A retrospective analysis was performed reviewing polysomnographic data (AHI) and anteroposterior cephalometric measurements of pharynx subregions: nasopharynx, oropharynx, hypopharynx. <strong>Results</strong>: The sample consisted of 30 patients. The mean body mass index was 29.60 kg/m<sup>2</sup> and the average age was 46.8 years. Nine patients presented severe OSA, seven had moderate OSA , seven had mild OSA, and seven were healthy.  The Pearson's correlation index between the anteroposterior dimension of the nasopharynx, oropharynx and hypopharynx and AHI was respectively -0.128 (p=0.517), -0.272 (p=0.162) and -0.129 (p=0.513).<strong> Conclusion: </strong>The correlation between anteroposterior linear dimension of the airway and OSA severity, assessed by AHI, was not positive. As an isolated parameter it did not correlate to the severity of the obstrucive sleep apnea syndrome and should be evaluated in conjunction with other factors.</p><p><strong> </strong></p><p><strong>Keywords</strong></p><p>Upper Airway; Obstructive sleep apnea; Cone beam CT.</p>

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