1.
Main screen :
- The main screen features the 27 regions standardised prostate reporting scheme (Fig. 1) :
- Axial sections represent the prostate base,
midgland and apex subdivised into :
- Posteriorly (p) : four regions (mediolobar and lateral).
- Anteriorly : four anterior regions (a) (mediolobar and
lateral) and the anterior stroma region (as).
This diagram allows precise localisation of the lesion in the peripheric,
transitionnal or extraprostatic (bladder,
seminal vesicles,
distal sphincter or extracapsular involvment) zone,
by direct finger touch.
- Two links are also featured on the main screen :
-
The « About... » button links to a general information page displaying contact informations,
version number,
legal mentions,
and recent updates (Fig. 2).
-
« The ESUR 2012 » button directs the user to a page displaying the PI-RADS scoring system table,
and a direct link to the pubmed abstract of ESUR guidelines (Fig. 3 and Fig. 4).
2.
Multiparametric evaluation :
- Once the localisation is selected,
the program displays a multiparametric caracterisation page where each parameter (T2,
diffusion,
perfusion and spectroscopy) can be evaluated independently (Fig. 5 and Fig. 6).
- For each parameter,
a multiple choice semiologic description is suggested,
based on the ESUR guidelines.
The user can then choose the most adequate semiologic description among those suggested (Fig. 7) :
- A complete description of the parameter turns the button color to green,
allowing the application to automatically determine a PI-RADS score for the selected parameter.
(Fig. 8).
- Dynamic contrast enhancement (DCE) (Fig. 9,
Fig. 10,
Fig. 11,
Fig. 12) and spectroscopy (Fig. 13,
Fig. 14,
Fig. 15) may require additional descriptions,
which is then indicated to the user by an orange colored button.
The PI-RADS scoring system for mandatory parameters (spectroscopy being optional) according to ESUR 2012 guidelines is reminded in Table 1, and extraprostatic lesion scoring is reminded in Table 2.
3.
Overall PI-RADS score
- After completing all parameters,
the overall PI-RADS score of the lesion is given as well as the associated probability of clinically significant malignancy,
using the five-point scales from ESUR guidelines (Fig. 16) :
-
Score 1 : clinically significant cancer is highly unlikely
-
Score 2 : clinically significant cancer is unlikely
-
Score 3 : clinically significant cancer is equivocal
-
Score 4 : clinically significant cancer is likely
-
Score 5 : clinically significant cancer is highly likely
- ESUR guidelines do not include specific recommandations for overall PI-RADS scoring.
However,
recent communications suggest that overall PI-RADS should not be determined by summing the individual scores, and recommend the use of T2 as predominant parameter in the transitional zone,
and diffusion as predominant parameter in the peripheral zone.
N.B.
: This application is not adapted to clinical situations of recurrence after treatment, in which the perfusion appears to be the predominant parameter.
4.
Downloading the application
- This PI-RADS application is available for free, on the google play network (by entering “PI-RADS” as keyword in the search engine),
where it can be automatically updated for all users once new recommandations are issued.
- Two versions have been released,
in english (v1.2) and french (v1.1).
Download link : https://play.google.com/store/apps/developer?id=Louis+Lassalle&hl=fr