Study design A prospective nonrandomized, longitudinal cohort study. Objective To evaluate the clinical outcomes of single-fraction radiosurgery as part of the management of metastatic spine tumors. Summary of background data The role of stereotactic radiosurgery for the treatment of spinal lesions has previously been limited by the availability of effective target immobilization and target tracking devices. Large clinical experience with spinal radiosurgery to properly assess clinical experience has previously been limited. Methods A cohort of 500 cases of spinal metastases underwent radiosurgery. Ages ranged from 18 to 85 years (mean 56). Lesion location included 73 cervical, 212 thoracic, 112 lumbar, and 103 sacral. Results The maximum intratumoral dose ranged from 12.5 to 25 Gy (mean 20). Tumor volume ranged from 0.20 to 264 mL (mean 46). Long-term pain improvement occurred in 290 of 336 cases (86%). Long-term tumor control was demonstrated in 90% of lesions treated with radiosurgery as a primary treatment modality and in 88% of lesions treated for radiographic tumor progression. Twenty-seven of 32 cases (84%) with a progressive neurologic deficit before treatment experienced at least some clinical improvement. Conclusions The results indicate the potential of radiosurgery in the treatment of patients with spinal metastases, especially those with solitary sites of spine involvement, to improve long-term palliation.

Radiosurgery for spinal metastases: clinical experience in 500 cases from a single institution.

This third edition text provides a completely revised and updated new version of this unique, modern, practical text that covers the strategic evaluation, specific approaches, and detailed management techniques utilized by expert colorectal surgeons caring for patients with complex problems–whether they result from underlying colorectal disease or from complications arising from previous surgical therapy. The format follows that of both a “how to” manual as well as an algorithm-based guide to allow the reader to understand the thought process behind the proposed treatment strategy. By making use of evidence-based recommendations, each chapter includes not only background information and diagnostic/therapeutic guidelines, but also provides a narrative by the author on his/her operative technical details and perioperative “tips and tricks” that they utilize in the management of these complex surgical challenges. Distinctive to this book, is the reliance on experts in the field including past presidents of the ASCRS, as well as multiple other national and internationally recognized surgeons, to lend their personal insight into situations where data may be more sparse, but individual and collective experience is paramount to making sound decisions and thereby optimizing patient outcomes. The text includes chapters on the assessment of risk and methods utilized to minimize perioperative complications. In addition, it incorporates sections covering the medical and surgical therapies for abdominal, pelvic and anorectal disease. Moreover, the technical challenges of managing complications resulting from the original or subsequent operations is addressed. The underlying focus throughout the text is on providing pragmatic and understandable solutions that can be readily implemented by surgeons of varying experience to successfully treat complex colorectal problems. However, it also goes beyond the technical aspects of colorectal surgery and includes special sections highlighting the essence of a surgeon; covering aspects involving the medical-legal, ethical, and economic challenges confronting surgeons. Throughout the text, each author provides an ongoing narrative of his/her individual surgical techniques along with illustrations and diagrams to “personally” take the reader through the crucial steps of the procedure, and key points of patient care inherent to that topic. Additionally, where appropriate, links to online videos give the reader an up-front look into technical aspects of colorectal surgery.

The ASCRS Textbook of Colon and Rectal Surgery

Study design Systematic literature review. Objective To determine the options, indications, and outcomes for conventional radiotherapy and radiosurgery for metastatic spine disease. Methods Three research questions were determined through a consensus among a multidisciplinary panel of spine oncology experts. A systematic review of the literature was conducted regarding radiotherapy and radiosurgery for metastatic spine disease using PubMed, Embase, the Cochrane Evidence Based Medicine Database, and a review of bibliographies of reviewed articles. Research questions 1. What are the clinical outcomes of the current indications for conventional radiotherapy alone and stereotactic radiosurgery for metastatic spine disease? 2. What are the current dose recommendations and fractionation schedules for conventional spine radiotherapy and stereotactic radiosurgery for metastatic spine disease? 3. What are the current known patterns of failure and complications after conventional spine radiation and stereotactic radiosurgery for metastatic spine disease? Results For conventional radiotherapy, the initial literature search yielded a total of 531 potentially relevant abstracts. Each of these abstracts was reviewed for relevance, and 62 were selected for in-depth review. Forty-nine studies met all the inclusion criteria. References from the articles included in the analysis and review articles were also examined for potential inclusion in the study. For conventional radiotherapy, 3 randomized trials (high-quality evidence), 4 prospective studies (moderate-quality evidence), and over 40 nonprospective data sets (low- or very-low-quality evidence) that included over 5000 patients in the literature were included in this review. Drawing from the same databases, a systematic search for radiosurgery yielded 195 abstracts, of which 29 met all inclusion criteria. They all represented single-institution reports (low- or very-low-quality data). No randomized data are available for spine radiosurgery. Conclusion A systematic review of the available evidence suggests that conventional radiotherapy is safe and effective with good symptomatic response and local control, particularly for radiosensitive histologies. A strong recommendation can be made with moderate quality evidence that conventional fractionated radiotherapy is an appropriate initial therapy option for patients with spine metastases in cases in which no relative contraindication exists. A systematic review of the available evidence suggests that radiosurgery is safe and provides an incremental benefit over conventional radiotherapy with more durable symptomatic response and local control independent of histology, even in the setting of prior fractionated radiotherapy. A strong recommendation can be made with low-quality evidence that radiosurgery should be considered over conventional fractionated radiotherapy for the treatment of solid tumor spine metastases in the setting of oligometastatic disease and/or radioresistant histology.

Radiotherapy and radiosurgery for metastatic spine disease: what are the options, indications, and outcomes?

The preferential accumulation of gold nanoparticles within tumors and the increased photoelectric absorption due to the high atomic number of gold cooperatively account for the possibility of significant tumor dose enhancement during gold nanoparticle-aided radiation therapy (GNRT). Among the many conceivable ways to implement GNRT clinically, a brachytherapy approach using low-energy gamma-/x-ray sources (i.e. Eavg 40%) could be achievable using 125I, 50 kVp and 169Yb sources and gold nanoparticles. When calculated at 1.0 cm from the center of the source within a tumor loaded with 18 mg Au g−1, macroscopic dose enhancement was 116, 92 and 108% for 125I, 50 kVp and 169Yb, respectively. For a tumor loaded with 7 mg Au g−1, it was 68, 57 and 44% at 1 cm from the center of the source for 125I, 50 kVp and 169Yb, respectively. The estimated MDEF values for 169Yb were remarkably larger than those for 192Ir, on average by up to about 70 and 30%, for 18 mg Au and 7 mg Au cases, respectively. The current MC study also shows a remarkable change in the photoelectron fluence and spectrum (e.g. more than two orders of magnitude) and a significant production (e.g. comparable to the number of photoelectrons) of the Auger electrons within the tumor region due to the presence of gold nanoparticles during low-energy gamma-/x-ray irradiation. The radiation sources considered in this study are currently available and tumor gold concentration levels considered in this investigation are deemed achievable. Therefore, the current results strongly suggest that GNRT can be successfully implemented via brachytherapy with low energy gamma-/x-ray sources, especially with a high dose rate 169Yb source.

https://iopscience.iop.org/article/10.1088/0031-9155/54/16/004/pdf

The dosimetric feasibility of gold nanoparticle-aided radiation therapy (GNRT) via brachytherapy using low-energy gamma-/x-ray sources

Parameters governing gold nanoparticle X-ray radiosensitization of DNA in solution

✓ Radiosurgery for brain tumors has been well established in the radiation oncology and neurosurgery fields. Radiosurgery of extracranial tumors such as those involving the spine is, however, still in the early stage because of difficulties in patient immobilization and organ motion. The authors describe an image-guided procedure for intensity-modulated spinal radiosurgery that was developed at Henry Ford Hospital.

Image-guided procedures for intensity-modulated spinal radiosurgery

The authors compared the relative dosimetric merits of Gamma Knife (GK) and CyberKnife (CK) in 15 patients with 26 brain metastases. All patients were initially treated with the Leksell GK 4C. The same patients were used to generate comparative CK treatment plans. The tissue volume receiving more than 12 Gy (V12), the difference between V12 and tumor volume (V12net), homogeneity index (HI), and gradient indices (GI25, GI50) were calculated. Peripheral dose falloff and three conformity indices were compared. The median tumor volume was 2.50 cm3 (range, 0.044–19.9). A median dose of 18 Gy (range, 15–22) was prescribed. In GK and CK plans, doses were prescribed to the 40–50% and 77–92% isodose lines, respectively. Comparing GK to CK, the respective parametric values (median ± standard deviation) were: minimum dose (18.2 ± 3.4 vs. 17.6 ± 2.4 Gy, p = 0.395); mean dose (29.6 ± 5.1 vs. 20.6 ± 2.8 Gy, p < 0.00001); maximum dose (40.3 ± 6.5 vs. 22.7 ± 3.3 Gy, p < 0.00001); and HI (2.22 ± 0.19 vs. 1.18 ± 0.06, p < 0.00001). The median dosimetric indices (GK vs. CK, with range) were: RTOG_CI, 1.76 (1.12–4.14) vs. 1.53 (1.16–2.12), p = 0.0220; CI, 1.76 (1.15–4.14) vs. 1.55 (1.18–2.21), p = 0.050; nCI, 1.76 (1.59–4.14) vs. 1.57 (1.20–2.30), p = 0.082; GI50, 2.91 (2.48–3.67) vs. 4.90 (3.42–11.68), p < 0.00001; GI25, 6.58 (4.18–10.20) vs. 14.85 (8.80–48.37), p < 0.00001. Average volume ratio (AVR) differences favored GK at multiple normalized isodose levels ( p < 0.00001). We concluded that in patients with brain metastases, CK and GK resulted in dosimetrically comparable plans that were nearly equivalent in several metrics, including target coverage and minimum dose within the target. Compared to GK, CK produced more homogenous plans with significantly lower mean and maximum doses, and achieved more conformal plans by RTOG_CI criteria. By GI and AVR analyses, GK plans had sharper peripheral dose falloff in most cases.

Comparing gamma knife and cyberknife in patients with brain metastases.

Introdution: Although flat-panel based X-ray imaging has been well tested in diagnostic radiology, its use as an image-guided-radiotherapy (IGRT) system in a treatment room is new and requires systematic assessment. Materials and Methods: BrainLab Novalis IGRT system was used for this study. It consists of two floor mounted kV X-ray tubes projecting obliquely into two flat-panel detectors mounted on the ceiling. The system automatically fuses the 2D localization images with 3D simulation CT image to provide positioning guidance. The following characteristics of the system were studied: (1) Coincidence of the isocenters between the IGRT and Linac; (2) Image quality; (3) Exposure; (4) Linearity, uniformity and repeatability. Results: (1) Localization accuracy and coincidence of the isocenters between the IGRT and Linac was better than 1-mm. (2) The spatial resolution was quantified using the relative modulation-transfer-function with f50=0.7-0.9 lp/mm. The variation of contrast-noise-ratio with technical settings was measured. (3) The maximal exposure of an image was less than 95 mR. An empirical relation between the exposure and the X-ray technical setting was derived. (4) The linearity, uniformity and repeatability of the system generally meet the requirements. Conclusion: The system can be safely and reliably used as a target localization device.

https://aapm.onlinelibrary.wiley.com/doi/pdf/10.1120/jacmp.v9i1.2318

Clinical assessment and characterization of a dual tube kilovoltage X-ray localization system in the radiotherapy treatment room.

The basic concept, design and performance of a novel needle-based x-ray system for medical applications are reported. The main principle of the system is based on a two-stage production of x-rays. The system comprises a conventional x-ray tube with an Ag anode, any known type of conditioning optics and a 2.2 mm diameter hollow needle with an interchangeable Mo target. The target can be moved along the needle axis and rotated around the needle axis. The needle x-ray device allows for adjustment in energy and flux intensity of the x-rays emitted by the target. The depth dependence of the intensity, dose rate as well as spatial and energy distribution of the radiation emitted by the target have been experimentally measured. The depth dose rate results have been compared with theoretical calculations using a Monte Carlo simulation of the x-ray production process. These studies have experimentally confirmed that the concept of this x-ray system is correct. Further improvement of the device can increase the dose rate up to the levels required for clinical applications.

http://iopscience.iop.org/article/10.1088/0031-9155/49/20/001/pdf

A novel needle-based miniature x-ray generating system.

Arteriovenous malformation (AVM), especially cryptic AVM, can cause highly variable cerebral neurological defects. Injection of 142Pr microspheres into arteries feeding an AVM in order to simulate radio-embolism has been proposed as a novel treatment method. To investigate optimization of radiation dose to the clinically important arterial wall area, preliminary dosimetric studies have been performed. Monte Carlo calculations were performed for simulated arteries filled with microspheres packed by random packing. Arterial radii from 0.05 mm to 3 mm and microsphere radii from 0.01 mm to 0.7 mm were used in the simulation. For constant arterial size, dose varied significantly with microspheres radius. Inter-arterial effect was also simulated using simplified geometry. For the inter-arterial sites, the dose rate was calculated between two arteries of the same size parallel to each other. The dose increased significantly for large arteries (>1 mm radius) filled with large microspheres (>0.3 mm radius). The dose increase between small arteries (<0.3 mm radius) was not as significant as that between large arteries. Overall results indicate that arterial size and microsphere size significantly affect the dose profile. This factor should be taken into account in future clinical applications.

Dose calculation of 142Pr microspheres as a potential treatment for arteriovenous malformations

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

S Lee

Author Tools

Chat about Author