Discussion
This meta-analysis aimed to evaluate the effectiveness of MRI-HIFU on
patients with uterine fibroids. The results showed that there was an
overall decrease in NPV% and tSSS% change. The health-related quality
of life among patients with uterine fibroids also improved with
follow-up; however, this was seen only in three studies and needs to be
assessed further. Studies involved in the meta-analysis have also
proclaimed improved reproductive outcomes. It has come to light that
reintervention was needed in 18-24% of patients. This meta-analysis has
included studies that have focussed on complete ablation for looking at
the overall effect of MR-HIFU.
The overall level of data, which was low to moderate, affected all of
the outcome criteria examined in this study. For inclusion, only
non-randomized, non-comparative trials were available. The sources of a
high risk of prejudice are linked to the sample designs themselves:
insufficient documentation of loss of follow-up and the possibility of
selection bias.
Increased expertise improves care effectiveness by reducing technical
errors and treatment time in extended patient cohorts. Xu et al.
registered the shortest sonication duration, suggesting that the
Chongqing method could increase treatment effectiveness. The pooled NPV
percent immediately after MR-HIFU was 70.24 percent, which is higher
than other reviews14,18, owing to the lack of
stringent treatment protocols. The distribution of dispersed points into
two classes showed a remarkable asymmetry in our findings.
Unfortunately, we were unable to provide a complete explanation. Through
bowel-interference avoidance methods, only a minor disparity was
discovered, meaning that this may lead to a higher NPV percent.
The pooled tSSS declined on average and continued to increase during
follow-up. There was no data available for more than a year. MR-HIFU was
not linked to other therapeutic choices in any of the trials included.
At a 3-months follow-up, Jacoby et al. compared MRgFUS to
placebo21 and found that the MRgFUS community had a
more significant tSSS decline, -31 vs. -13 points. We looked for other
uterine fibroid studies that used the UFS-QoL questionnaire to equate
the tSSS of MR-HIFU to other treatment alternatives (UAE, hysterectomy,
and myomectomy). Similarly, studies by Spies JB30 and
Manyonda IT31 have also reported a decrease in tSSS%
change in myomectomy and hysterectomy, and the present meta-analysis has
indicated an overall tSSS% change of 49.27, which is comparable to
hysterectomy and myomectomy. Few studies reported health-related quality
of life, but the enrolled studies have improved uterine fibroid-related
quality of life.
Fibroid shrinkage was shown in all the studies, and the percentage of
shrinkage ranged over time, indicating that fibroids will continue to
shrink in volume for at least a year. The relationship between fibroid
shrinkage and NPV percent was marginally significant, implying that a
higher NPV percent could lead to more fibroid shrinkage. Please keep in
mind that a follow-up MRI exam is costly and mostly needless.
The reintervention has seen in Tan et al.20, Mindjuk
et al.19, and Chen et al.16 was 9%,
12.7%, and 0.9%, respectively, while other studies did not report the
need for reintervention on the follow-up period. This particular result
pointed at the efficacy of the procedure. The procedure of MR-HIFU is
non-invasive and does not indicate any effect on the reproductive
outcome of the patients after the treatment. None of the studies has
included the reproductive outcome and hence raised concern. However,
studies by Lee JS32 and Cheung VY33have shown no effect on the Anti-Mullerian Hormone, indicating that
women can try for pregnancy after treating uterine fibroids.
Just two SAEs were identified in older studies24,39,
which may be clarified by a slight learning curve effect when MR-HIFU
was first used in clinical practice [13]. As AE was stratified by
method, trials using the Sonalleve system had slightly more AE than
trials using the ExAblate device 14,15,17,22. Two
Ex-Ablate reports, on the other hand, reported ‘no unforeseen or major
AE,’ implying under-reporting16,27. Furthermore, there
is no agreement about how to define AE in the context of MR-HIFU. For
example, although irregular vaginal discharge is often classified as AE,
fibroid expulsion was identified as a common finding in 21% of ExAblate
patients 19. Surprisingly, a Sonalleve study
classified constitutional symptoms as AE, although none of the other
studies did 22. Although a reporting bias may clarify
the disparity in AE between Sonalleve and ExAblate, more research is
needed in the future.
These treatment modalities may have shown to be cost
effective34-38 but not included in this analysis.
MR-HIFU can be considered a cost-effective treatment for patients ready
to pay.
Methodological flaws were to blame for the meta-analysis’s flaws.
Standard deviations were often estimated. There was a lack of follow-up
in some trials, and some sub-studies had different sample
sizes41. As a consequence, the findings should be
viewed with caution. Furthermore, since the findings are based on
published means rather than actual patient records, the ecological
fallacy may have influenced the results. We questioned if we should
generalize our findings because of the significant and often mysterious
heterogeneity in each outcome parameter. However, since we used a
random-effects model for meta-analysis40, this
approach is accurate.
Even though MR-HIFU has been used to treat uterine fibroids for 14
years, it is still not widely used or reimbursed worldwide. The gold
standard for obtaining reimbursement is a randomized clinical
experiment, and one is currently underway to compare UAE and
MR-HIFU42. However, they had difficulty selecting
volunteers, and some patients refused to be randomly assigned. As a
result, randomized experiments are challenging to perform and face
statistical difficulties. More extensive retrospective randomized cohort
trials with longer follow-up are needed to establish the role of MR-HIFU
in the management of symptomatic uterine fibroids before it can be used
in routine clinical care.