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

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.

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

Neurosurgical FOCUS ◽

10.3171/2016.9.focus16356 ◽

2017 ◽

Vol 42 (1) ◽

pp. E11 ◽

Cited By ~ 9

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.

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

Journal of Neurosurgery Spine ◽

10.3171/2009.10.spine09249 ◽

2010 ◽

Vol 12 (4) ◽

pp. 413-420 ◽

Cited By ~ 13

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.

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Application of 3D tooth model for monitoring of implant space and inter-root distance without radiographs: a proof of concept study

International Journal of Implant Dentistry ◽

10.1186/s40729-020-00253-3 ◽

2020 ◽

Vol 6 (1) ◽

Author(s):

Kyungmin Lee ◽

Gyu-Hyoung Lee

Keyword(s):

Computed Tomography ◽

Radiation Exposure ◽

Cone Beam Computed Tomography ◽

Alveolar Bone ◽

Tooth Movement ◽

Treatment Evaluation ◽

Cone Beam ◽

Proof Of Concept ◽

Cbct Image ◽

Root Position

Abstract Background Radiographs are integral in evaluating implant space and inter-root distance. The purpose of this report is to introduce a method for evaluating the 3D root position with minimal radiation using a 3D tooth model composed of an intraoral-scanned crown and a cone-beam computed tomography (CBCT)-scanned root. Materials and methods Intraoral scan and CBCT scan of the patient were obtained before treatment. In the CBCT image, tooth segmentation was performed by isolating individual teeth from the maxillary and mandibular alveolar bone using software program. The 3D tooth model was fabricated by combining segmented individual teeth with the intraoral scan. Results A post-treatment intraoral scan was integrated into the tooth model, and the resulting position of the root could be predicted without additional radiographs. It is possible to monitor the root position after a pretreatment CBCT scan using a 3D tooth model without additional radiographs. Conclusion The application of the 3D tooth model benefits the patient by reducing repeated radiation exposure while providing the clinician with a precise treatment evaluation to monitor tooth movement.

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Intraoperative cone beam computed tomography for detecting residual stones in percutaneous nephrolithotomy: a feasibility study

Urolithiasis ◽

10.1007/s00240-021-01259-1 ◽

2021 ◽

Author(s):

R. A. Kingma ◽

M. J. H. Voskamp ◽

B. H. J. Doornweerd ◽

I. J. de Jong ◽

S. Roemeling

Keyword(s):

Computed Tomography ◽

Percutaneous Nephrolithotomy ◽

Cone Beam Computed Tomography ◽

University Hospital ◽

Cone Beam ◽

Cross Sectional ◽

The Mean ◽

Residual Stones ◽

Residual Fragments

AbstractCone beam computed tomography (CBCT) provides multiplanar cross-sectional imaging and three-dimensional reconstructions and can be used intraoperatively in a hybrid operating room. In this study, we investigated the feasibility of using a CBCT-scanner for detecting residual stones during percutaneous nephrolithotomy (PCNL). Intraoperative CBCT-scans were made during PCNL procedures from November 2018 until March 2019 in a university hospital. At the point where the urologist would have otherwise ended the procedure, a CBCT-scan was made to image any residual fragments that could not be detected by either nephroscopy or conventional C-arm fluoroscopy. Residual fragments that were visualized on the CBCT-scan were attempted to be extracted additionally. To evaluate the effect of this additional extraction, each CBCT-scan was compared with a regular follow-up CT-scan that was made 4 weeks postoperatively. A total of 19 procedures were analyzed in this study. The mean duration of performing the CBCT-scan, including preparation and interpretation, was 8 min. Additional stone extraction, if applicable, had a mean duration of 11 min. The mean effective dose per CBCT-scan was 7.25 mSv. Additional extraction of residual fragments as imaged on the CBCT-scan occurred in nine procedures (47%). Of the follow-up CT-scans, 63% showed a stone-free status as compared to 47% of the intraoperative CBCT-scans. We conclude that the use of CBCT for the detection of residual stones in PCNL is meaningful, safe, and feasible.

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Height difference between the vestibular and palatal walls and palatal width: a cone beam computed tomography approach

BMC Oral Health ◽

10.1186/s12903-020-01322-0 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

P. López-Jarana ◽

C. M. Díaz-Castro ◽

A. Falcão ◽

C. Falcão ◽

J. V. Ríos-Santos ◽

...

Keyword(s):

Computed Tomography ◽

Cone Beam Computed Tomography ◽

Cone Beam ◽

Bone Thickness ◽

Height Difference ◽

Mean Values ◽

The Mean ◽

Maxilla And Mandible ◽

Palatal Bone ◽

Two Parameters

Abstract Background The objective of this study was to measure two parameters involved in tri-dimensional implant planning: the position of the buccal and palatal bone wall and the palatal thickness. Methods Cone beam computed tomography (CBCT) images (Planmeca ProMax 3D) of 403 teeth (208 upper teeth and 195 lower teeth) were obtained from 49 patients referred to the Dental School of Seville from January to December 2014. The height difference between the palatal and buccal walls was measured on the most coronal point of both walls. The thickness of the palatal wall was measured 2 mm from the most coronal point of the palatal wall. Results The mean values in the maxilla were 1.7 ± 0.9 mm for central and lateral incisors, 2.2 ± 1.7 mm for canines, 1.6 ± 0.9 mm for premolars and 1.9 ± 1.5 mm for molars. In the lower jaw, the mean values were 1.3 ± 0.8 mm for incisors, 1.7 ± 1.2 mm for canines, 2.3 ± 1.3 mm for premolars, and 2.6 ± 1.7 mm for molars. In the upper jaw, more than 55% of maxillary teeth (excluding second premolars and molars) presented mean height differences greater than 1 mm. In the mandible, more than 60% of incisors showed a buccal bone thickness of 1 mm from the apical to lingual aspect. All teeth except the second premolar presented a buccal wall located more than 1 mm more apically than the lingual bone wall. Conclusions The buccal bone wall is located more apically (greater than 1 mm) than the palatal or lingual table in most of the cases assessed. The thickness of the palatal or lingual table is also less than 2 mm in the maxilla and mandible, except in the upper canines and premolars and the lower molars.

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Ionizing radiation and its considerations in imaging diagnosis: comparison of absorbed dose between cone beam computed tomography and multi-detector computed tomography in the head and neck

Radioprotection ◽

10.1051/radiopro/2021006 ◽

2021 ◽

Author(s):

P.L.E. Oliveira ◽

C.R. Starling ◽

C.L.P. Maurício ◽

F.R. Guedes ◽

M.A. Visconti ◽

...

Keyword(s):

Computed Tomography ◽

Head And Neck ◽

Cone Beam Computed Tomography ◽

Absorbed Dose ◽

Cone Beam ◽

Thermoluminescent Dosimeters ◽

Organ Tissue ◽

The Mean ◽

Average Adult ◽

Multi Detector Computed Tomography

Introduction: The objective of this study was to compare the mean absorbed dose in patients undergoing head and neck examinations using two cone beam computed tomography (CBCT, Kodak and i-CAT) and one multi-detector computed tomography (MDCT). Methods: Three thermoluminescent dosimeters (TLDs), calibrated in air kerma, were positioned in 24 regions of the head and neck of a phantom simulating an average adult. The mean absorbed dose (mGy) values in these positions, for different organs and tissues, were obtained using correction factors, considering the ratio between the mass energy absorption coefficients of organ/tissue and air. Comparison between radiation doses in the most radiosensitive regions was done by calculating the ratio of these dose values, with propagated uncertainty. Results: The dose in all regions was significantly higher for MDCT when compared to CBCT. Concerning CBCT equipment, the Kodak device had a higher absorbed dose than the i-CAT for most of the regions tested. The uncertainty of the i-CAT was greater than that of the Kodak. Conclusion: Due to the considerable difference between absorbed doses, emphasizing the higher dose values obtained in MDCT, the dissemination of CBCT application in medicine is recommended, as well as further studies to broaden the criteria for use.

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Comparison of the Hounsfield Unit Values Obtained From Cone-Beam Computed Tomography (CBCT) and Multidetector Computed Tomography (MDCT) Images for Different Bone Densities

Journal of Contemporary Medical Sciences ◽

10.22317/jcms.v7i2.943 ◽

2021 ◽

Vol 7 (2) ◽

Author(s):

Atefeh Khavid ◽

Mojgan Sametzadeh ◽

Mostafa Godiny ◽

Mohammad Mehdi Moarrefpour

Keyword(s):

Computed Tomography ◽

Cone Beam Computed Tomography ◽

Pearson Correlation ◽

Hounsfield Unit ◽

Cone Beam ◽

Ct Scanner ◽

Significance Level ◽

Dental Practitioners ◽

Significant Difference ◽

The Mean

Background and objective: In recent years, cone-beam computed tomography (CBCT) has become a key diagnostic tool in dentistry. CBCT can provide 3D images of the maxillofacial area to help dental practitioners in diagnosis and treatment, especially implant placement and treatment of pathogenic lesions. This study aimed to compare the Hounsfield Unit (HU) values obtained from CBCT images for bones of different densities with the corresponding HU values from MDCT images. Materials and methods: cube-shaped bone blocks of identical size were cut from the middle section of the cow ribs and femur area such that they had a layer of cortical bone in their buccal, lingual, and top surfaces and trabecular bone in the middle. MDCT scans were performed using a Somatom Sensation Ct Scanner. After determining HU from the results of these scans, nine suitable specimens from different ranges of HU were chosen for comparison. HU of the CBCT images was computed by the dedicated software of the CBCT machine. Finally, HU values obtained from MDCT and CBCT were compared. Data analysis was performed using SPSS version 25 at the 0.05 significance level. Results: The results showed a statistically significant difference between the mean HU from MDCT images and the mean HU from CBCT images (P<0.05). For similar specimens, CBCT produced higher mean HU values than MDCT. The Pearson correlation test detected a significant direct relationship between the HU values of specimens in MDCT and CBCT (P<0.05). Conclusion: For the tools and software used in this study, there was no significant difference between the HU values obtained from MDCT and CBCT, but the mean HU obtained from CBCT was higher than that from MDCT.

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Intrafractional motion in stereotactic body radiotherapy of spinal metastases utilizing cone beam computed tomography image guidance

Physics and Imaging in Radiation Oncology ◽

10.1016/j.phro.2019.10.001 ◽

2019 ◽

Vol 12 ◽

pp. 1-6 ◽

Cited By ~ 2

Author(s):

Jørund Graadal Svestad ◽

Christina Ramberg ◽

Birgitte Skar ◽

Taran Paulsen Hellebust

Keyword(s):

Computed Tomography ◽

Cone Beam Computed Tomography ◽

Stereotactic Body Radiotherapy ◽

Image Guidance ◽

Spinal Metastases ◽

Cone Beam ◽

Tomography Image ◽

Intrafractional Motion ◽

Computed Tomography Image

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Postoperative Assessment of Incisor Dental Implants Using Cone-Beam Computed Tomography

Journal of Oral Implantology ◽

10.1563/aaid-joi-d-09-00080 ◽

2010 ◽

Vol 36 (5) ◽

pp. 377-384 ◽

Cited By ~ 17

Author(s):

Munetaka Naitoh ◽

Hiromitsu Nabeshima ◽

Hisashi Hayashi ◽

Takehiko Nakayama ◽

Kenichi Kurita ◽

...

Keyword(s):

Computed Tomography ◽

Dental Implants ◽

Cone Beam Computed Tomography ◽

Bone Grafts ◽

Cone Beam ◽

Postoperative Assessment ◽

Labial Side ◽

Bone To Implant Contact ◽

The Mean ◽

Postoperative Findings

Abstract The bone configuration surrounding anterior dental implants was postoperatively assessed using cone-beam computed tomography (CBCT). In 21 patients with a mean age of 41.5 years, 36 implants placed in the incisor region were postoperatively evaluated using CBCT. The rate of bone-to-implant contact (%) was calculated. The mean rate of bone-to-implant contact on the labial side was 78.3% with and 65.3% without bone grafts. The postoperative findings of incisor implants could be assessed using CBCT.

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