Predictive Model for the Diagnosis of Uterine Prolapse Based on Transperineal Ultrasound

Round 1

Reviewer 1 Report

Paper seems to meaningfully advance the field. 

HOWEVER, i'd like to see a comparison of your method with the standard method that uses only 'prolapse if ultrasound shows > 15 mm change'.

moreover, for their model and the standard model, they should report each of sensitivity and specificity and positive & negative predictive value (not just sensitivity as discussed here).

Author Response

Reviewer 1

 

Paper seems to meaningfully advance the field. 

HOWEVER, i'd like to see a comparison of your method with the standard method that uses only 'prolapse if ultrasound shows > 15 mm change'.

Answer: We have included a text that refers to video 1 and answers the question suggested by the reviewer.

Text: “In the example of figure 1, the difference in the pubis-uterine fundus distance at rest and with the Valsalva maneuver is 17 mm, according to the cut-off point of ≥15 mm (7) the diagnosis of PU would be established. However, when applying the software this risk varies depending on age (video1)”

moreover, for their model and the standard model, they should report each of sensitivity and specificity and positive & negative predictive value (not just sensitivity as discussed here).

In order to establish the values ​​that you tell me (sensitivity and specificity and positive and negative predictive value) we need to determine an optimal point (greater specificity without losing sensitivity) to diagnose PU. However, the objective of our study is the design of the software without establishing a reference point to determine the UP, since we need a validation of the Software to establish said point. To this end, we are working on another multi-centre study to resolve the question that you raise.

 

In any case, since you have asked us for these values, we clarify that the optimal point (greater specificity without losing sensitivity) to detect the PU is the 50% probability estimated by the software. Based on this, we determine a simulation assimilating different prevalences of the UP of the population studied for you to check the sensitivity and specificity and the positive and negative predictive value:

 

With a population with a prevalence of PU of 7%, the cut-off point of the software at 50% has:

• Sensitivity = 0.92 (95% CI: 0.82-0.97)
• Specificity = 0.86 (95% CI: 0.71-0.95)
• Positive predictive value = 0.34 (95% CI: 0.09-0.59)
• Negative predictive value = 0.99 (95% CI: 0.99-1)

 

With a population with a prevalence of PU of 15%, the cut-off point of the software at 50% has:

• Sensitivity = 0.92 (95% CI: 0.83-0.97)
• Specificity = 0.86 (95% CI: 0.71-0.95)
• Positive predictive value = 0.55 (95% CI: 0.30-0.79)
• Negative predictive value = 0.98 (95% CI: 0.97-0.99)

 

With a population with a prevalence of PU of 23%, the cut-off point of the software at 50% has:

• Sensitivity = 0.92 (95% CI: 0.82-0.97)
• Specificity = 0.86 (95% CI: 0.71-0.95)
• Positive predictive value = 0.67 (95% CI: 0.46-0.88)
• Negative predictive value = 0.97 (95% CI: 0.95-0.99)

 

 

Reviewer 2 Report

 

tomography-1776669

 

The manuscript entitled “Predictive model for the diagnosis of uterine prolapse based on transperineal ultrasound” analyzed the development of a model to predict the risk of uterine prolapse with transperineal ultrasound. Authors concluded that using a model based on the difference in the pubis-uterine fundus distance at rest and with the Valsalva maneuver and the age of the patient could predict until 96 % of patients with uterine prolapse.

The topic of this Manuscript is interesting and falls within the scope of Tomography journal.

However, a few but important points have to be addressed before the study is suitable for publication.

Introduction: Authors should describe the prevalence and incidence of the uterine prolapse, briefly referring to PMID: 23692627, PMID: 19214994

Introduction: The use of trasnperineal ultrasound has been used for several aspects of woman pelvis, from surgical follow up of genital prolapse to labor. Authors should improve this section at least briefly referring to:  PMID: 35656763, PMID: 20173318

Methods: Please Authors better specify the measurement taken: which distance they analyze? It is not clear from the text. Moreover improve the caption in figure 1.

Results: Please correct some typos in this section such as in table 2.

Discussion: Please use a subheading for the limitations and strength section.

Conclusion: Please improve this section. What is the authors’ experience about this case series? What is the new of this manuscript compared with the previous literature?

Author Response

Reviewer 2

 

The manuscript entitled “Predictive model for the diagnosis of uterine prolapse based on transperineal ultrasound” analyzed the development of a model to predict the risk of uterine prolapse with transperineal ultrasound. Authors concluded that using a model based on the difference in the pubis-uterine fundus distance at rest and with the Valsalva maneuver and the age of the patient could predict until 96 % of patients with uterine prolapse.

The topic of this Manuscript is interesting and falls within the scope of Tomography journal.

However, a few but important points have to be addressed before the study is suitable for publication.

Introduction: Authors should describe the prevalence and incidence of the uterine prolapse, briefly referring to PMID: 23692627, PMID: 19214994

Answer: It has been included in the text

Text: The prevalence of prolapse, this accompanied by loss of vaginal oruterine support, ranges from 6%-24% stage 0, to 38%-48% stage I, to 35%-48% stage II, while 2–6% of the general population have totalprolapse beyond the vaginal entrance, stage III (1,2)

 

1. Salvatore S, Athanasiou S, Digesu GA, Soligo M, Sotiropoulou M, Serati M, et al. Identification of risk factors for genital prolapse recurrence. Neurourol Urodyn. 2009;28(4):301-4. doi: 10.1002/nau.20639.
2. 31 Tsikouras P, Dafopoulos A, Vrachnis N, Iliodromiti Z, Bouchlariotou S, Pinidis P, et al. Uterine prolapse in pregnancy: risk factors, complications and management. J Matern Fetal Neonatal Med. 2014 Feb;27(3):297-302.

 

Introduction: The use of trasnperineal ultrasound has been used for several aspects of woman pelvis, from surgical follow up of genital prolapse to labor. Authors should improve this section at least briefly referring to:  PMID: 35656763, PMID: 20173318

Answer: It has been included in the text

Text: The use of trasnperineal ultrasound has been used for several aspects of woman pelvis, from surgical follow up of genital prolapse to labor (3,4).

3. Molina FS, Nicolaides KH. Ultrasound in labor and delivery. Fetal Diagn Ther. 2010;27(2):61-7.
4. Gugliotta G, Schiattarella A, Giunta M, De Franciscis P, Potito S, Calagna G. Translabial ultrasound evaluation after tension-free transobturator tape technique: Outcomes based on the tape's position. Int J Gynaecol Obstet. 2022 Jun 3. doi: 10.1002/ijgo.14295.

 

 

Methods: Please Authors better specify the measurement taken: which distance they analyze? It is not clear from the text. Moreover improve the caption in figure 1.

Answer: It has been added to the text.

Figure 1. Ultrasound of uterine prolapse. Image A shows the midsagittal plane of the pelvic floor at rest where the red line delimits the posteroinferior margin of the pubis and the yellow line the pubis-fundus distance at rest. Image B shows the midsagittal plane of the pelvic floor in Valsalva where the red line establishes the posteroinferior margin of the pubis and the green line the pubis-fundus distance in Valsalva.

Results: Please correct some typos in this section such as in table 2.

Answer: Typos have been fixed

Discussion: Please use a subheading for the limitations and strength section.

Answer: It has been added to the text.

Conclusion: Please improve this section. What is the authors’ experience about this case series? What is the new of this manuscript compared with the previous literature?

Answer: It has been added to the text.

Text: We designed a model based on the difference in the pubis-uterine fundus distance at rest and with the Valsalva maneuver and the age of the patient that can predict 96.7% of patients with UP. We have established a sotware based in an easy-to-apply model using two-dimensional ultrasound that includes age as a clinical parameter to predict UP.

Reviewer 3 Report

Dear author

 

Thank you for the submission of your paper to our journal. I’ve just read your article and found many problems in your article as follows;

 

Line 69

You defined Valme University Hospital of Seville as Hospital 1. Where is Hospital 2 in your paper? Why did you not use the word Hospital1 in your figures and hospitals.

 

Line84-6 The sentence descried just below is grammatically incorrect.

The ultrasound machines used were a Toshiba® 500 Aplio (Toshiba Medical Systems 84 Corp., Tokyo, Japan) with a PVT‐675MV 3‐dimensional abdominal probe covered by a 85 sterile glove. 

Line 99

Why did you spell out LAM in its first appearance?

 

Line 104

What does the Valsalva maximum imply?

 

Figure 2

You should more precisely explain the figures.

 

Line 138-9

You should not exclude the patient with poor ultrasound images. 

 

Table 2

What did you mean the word L SEP just after the Valsalva?

 

Figures 2 and 3

Where were the A and B curves?

 

Figure 4

In the text, you commented “specialists can optimize the type of surgery”. You should  explain more details in the figure legends. In addition, what did the number of 16,205727 and 94,774748 express?

 

Author Response

Reviewer 3

 

Dear author

 

Thank you for the submission of your paper to our journal. I’ve just read your article and found many problems in your article as follows;

 

Line 69

You defined Valme University Hospital of Seville as Hospital 1. Where is Hospital 2 in your paper? Why did you not use the word Hospital1 in your figures and hospitals.

 

Answer: There was an error in the data. Has been deleted (Hospital 1)

 

Line84-6 The sentence descried just below is grammatically incorrect.

The ultrasound machines used were a Toshiba® 500 Aplio (Toshiba Medical Systems 84 Corp., Tokyo, Japan) with a PVT‐675MV 3‐dimensional abdominal probe covered by a 85 sterile glove. 

Answer: It has been corrected in the text

Text: The ultrasound machines used were a Toshiba® 500 Aplio (Toshiba Medical Systems Corp., Tokyo, Japan) with a PVT‐675MV 3‐dimensional abdominal probe.

Line 99

Why did you spell out LAM in its first appearance?

Answer: It has been corrected in the text

Text: The integrity of the levator ani muscle (LAM) was assessed at maximum contraction using tomographic ultrasound imaging, as previously described (17,18). Complete avulsion was diagnosed when abnormal LAM insertion was observed in the three central sections.

Line 104

What does the Valsalva maximum imply?

 

Answer: It has been corrected in the text

Text: Three volume measurements were taken for each patient: at rest, with the Valsalva maneuver (for a minimum of 6 s, assessed with the cine loop preventing the presence of levator coactivation (14))

Figure 2

You should more precisely explain the figures.

 Answer: I have changed the explanation of figure 1 and have corrected figures 2 and 3.

Line 138-9

You should not exclude the patient with poor ultrasound images. 

 Answer: We have only excluded a single patient with a poor image in which we could not measure the uterine fundus since the patient's collaboration was not adequate

Table 2

What did you mean the word L SEP just after the Valsalva?

 Answer: Dear reviewer. I do not observe the data that you refer to in table 2. I enclose table 2.

Table 2:

	UP (ICS POP-Q) (n=66)	CE without UP (ICS POP-Q) (n=40)	p	95% CI
Levator hiatal area (cm 2)
Rest	20.8±5.3	23.1±6.1	0.038	-4.6; -0.1
Valsalva	31.2±8.7	33.0±8.5	0.297	-5.2; 1.6
LAM avulsion	19(28.8%)	6(15.0%)	0.156	-2.1; 29.7
Ballooning	49(74.2%)	35(87.5%)	0.139	-28.3; 1.8
Pubis-uterine fundus measurement
Rest	-66.3±12.8	-74.8±16.8	0.008	2.3; 14.6
Valsalva	-41.2±14.8	-67.9±17.3	<0.0005	20.5; 33.0
Pubis-uterine fundus measurement Difference between rest and Valsalva	25.1±11.7	6.8±4.4	<0.0005	15.2; 21.5

 

Figures 2 and 3

Where were the A and B curves?

 I have corrected figures 2 and 3

Figure 4

In the text, you commented “specialists can optimize the type of surgery”. You should  explain more details in the figure legends. In addition, what did the number of 16,205727 and 94,774748 express?

Answer: We have changed the legend of figure 4, clarifying how the software can personalize the risk that the patient suffers from a PU and helping the surgeon to confirm his clinical diagnosis.

Text: Figure 4. Example of the use of the binary model based on the difference in the pubis-uterine fundus distance at rest and with the Valsalva maneuver and age as a predictor of UP. The image above shows how a 42-year-old patient with a difference in the pubis-uterine fundus distance at rest and with the Valsalva maneuver of 17 mm has a personalized risk of having a PU of 16.2%. The lower image shows how a 66-year-old patient with a difference in the pubis-uterine fundus distance at rest and with the Valsalva maneuver of 17 mm has a personalized risk of having a PU of 94.8%.

 

Round 2

Reviewer 1 Report

thank you for responding to my concerns.

Reviewer 2 Report

The Authors improved the quality of the manuscript as requested.

Reviewer 3 Report

Dear author

 

Thank you for the re-submission of your article to our journal. I confirmed the revised your manuscript and felt it appropriate for the publication.