Visual Evaluation of Image Quality of a Low Dose 2D/3D Slot Scanner Imaging System Compared to Two Conventional Digital Radiography X-ray Imaging Systems
, Bo Mussmann 1,3, Alistair Mackenzie 4, Oke Gerke 1,5, Gitte Maria Jørgensen 3, Thor Eriksen Bechsgaard 3, Janni Jensen 1,3, Lone Brunshøj Olsen 3 and Poul Erik Andersen 1Round 1
Reviewer 1 Report
This paper compared the image quality of low dose 2D/3D slot scanner (LDSS) and 2 conventional digital radiography (DR) of chest and knee. Ten posterior-anterior (PA) and ten lateral (LAT) images of a chest anthropomorphic phantoms and a knee phantom were acquired for image quality scoring. Three radiologists (chest) and three experienced radiographers (knee) score the image quality with Use VGA-based scale. This is a carefully done study and the findings are of considerable interest. I listed a few minor revisions below.
- In table 2, the tube voltage of LDSS for knee examination is 68 KV, which is not lower than DR1 57 kV, and DR2 63kV. Why should LDSS use a higher tube voltage?
- In table 6 and 8, the column of projections is labeled incorrectly with the knee. It should be labeled with a chest.
- The inter-observer agreement on criteria 4 “diaphragm and lateral costo-phrenic (CP) angles” is in the range of “Slight agreement.” The image quality regarding this point is important to evaluate the clinical condition of pleural effusion etc. it would be even better if some extra data were added.
- The inter and intra-observer agreement on the knee examination in criteria 2 “sharpness of trabeculae in the medial femoral condyle” are in the range of “Slight agreement.” The image quality regarding this point is crucial for a radiologist. It would be even better if some extra data were added.
- In the discussion, the author pointed out the scan time of LDSS is longer. The image quality of CP angle is one of the image difficulties of LDSS. The author may examine in more detail what kind of effect would appear due to scan time.
Author Response
Dear reviewer,
Please find the attached responses to your comments.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Rows 43-44: There is a grammar mistake in the sentence, 'The two-dimensional images of LDSS imaging system allows to derive..."
Row 45: Avoid starting a sentence with acronym, 'The LDSS imaging system...'.
Rows 47-48: "the LDSS imaging system is not commonly used for general radiology examinations." Explain why not?
Rows 70-71: "There are several methods for quantifying image quality, and all have their advantages and disadvantages.", so why did you decide to use the one in your study compared to the other methods?
Row 107: missing period.
Row 169: grammar mistake in, "to increase the dose level and achieves higher image quality".
Rows 172-173: "Ten radiographic images of the anthropomorphic (chest) and extremity (knee) phantom images were acquired in PA", so, images of images were acquired?
You claim 10 images were acquired. Can you include some table that clearly states all the parameters of all 10 images? It appears confusing as it is now. One has to read and reread everything to understand where all the 10 images come from.
Row 181: "The observers were cored"?
You claim that the main limitation of this study is that although the chest anthropomorphic and knee phantoms are realistic, the resultant images do not perfectly mimic clinical images. What about the fact that you only have 3 experts scoring the images? Hard to take a statistical analysis seriously with only three values. Please, justify that.
Author Response
Dear Reviewer
Please find the attached responses to your comments.
Author Response File: Author Response.pdf
