Evidence map›Paper›PMID 26180706›Full record

ArticleCureus2015

How Low Should You Go: Choice of Minimum Dose Prescription in Cranial Radiosurgery.

David Roberge, Claudie Leclerc-Champagne, Robert Doucet, Jan Seuntjens

Open access · diamondAbstract read
In one paragraph

Article in Cureus, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact, top 93% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed, 1 citations in OpenAlex.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

4 authors at 1 institution in 1 country.

David RobergeDepartment of Oncology, Division of Radiation Oncology, McGill University Health Center ; Department of Radiology, Radiation Oncology and Nuclear Medicine, University of Montreal ; Department of Radiation Oncology, Centre hospitalier de l'université de Montréal (CHUM) ; Department of Oncology, Division of Radiation Oncology, McGill University Health Center.
Claudie Leclerc-ChampagneDepartment of Radiation Oncology, Centre hospitalier de l'université de Montréal (CHUM).
Robert DoucetDepartment of Radiation Oncology, Centre hospitalier de l'université de Montréal (CHUM).
Jan SeuntjensDivision of Medical Physics, McGill University Health Center.
Université de Montréal · CA

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundIn radiosurgery, the convention has been to prescribe radiation dose to a "covering isodose volume". This is presumed to be the minimum dose received by the entire tumor. Our purpose was to review our practice, assess different means of specifying a prescription isodose, and test how reliable they were in the face of various calculation methodologies.

methodsDifferent minimum doses were calculated using three calculation methods for 20 brain targets and compared to the original physician intent. Monte Carlo (MC) calculations were run down to 2% (1 sigma) statistics. Voxel size depended on the imaging field of view and the calculation engine. For pencil beam convolution ("finite size pencil beam" - FSPB) calculations with or without heterogeneity correction (Methods 1-2), the calculation grid matched the CT scan resolution. For MC calculations (Method 3), the highest available in-plane resolution was 256 x 256 pixels. The median voxel volume was thus 0.58 mm(3) (0.47 to 0.95 mm(3)) for FSPB and 2.3 mm(3) (1.87 to 3.80) for MC.

resultsThe absolute minimum target dose varied substantially between the three calculation methods - up to 25% difference between Methods 1 and 3. The differences were reduced when comparing near-minimum doses with absolute minimal volumes ΔV, DPTV-ΔV. The median difference in the isodose covering the PTV-0.03 cm(3) was 0% for Methods 1 and 2 and 3.6% for Methods 1 and 3. The median difference in the isodose covering the PTV-0.01 cm(3) was 0% for Methods 1 and 2 and 2.2% for Methods 1 and 3. In our data, the smaller the volume in which the minimum dose is calculated, the more sensitive this calculation was to dose calculation parameters. The standard deviation of the difference between physician intent and the isodose covering the PTV-0.01 cm(3) was 2.9% (range from -3.3% to 9.3%).

conclusionIn radiosurgery, absolute minimum doses are sensitive to changes in dose calculation grids and dose calculation algorithms. Based on our experience, standardizing dose prescription to the isodose volume covering the PTV-0.01 cm(3) or the PTV-0.03 cm(3) would have little impact on clinical practice and would be relatively insensitive to dose calculation parameters.

Indexed as

isodoseprescriptionradiosurgerytarget dose

Identifiers

PMID26180706
PMCPMC4494511
OpenAlexW1481969945

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.