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Abstract

Aim We investigated the natural history of fetal ovarian cysts to estimate the risk of torsion according to size. Methods Cases were identified from 1/1/2000 until 1/1/2015. Data were collected pre- and postnatally on cyst size and sonographic features until an outcome of surgery, torsion, or resolution. Fisher's exact test categorical data and logistic regression for the significance of size on torsion; P value < 0.05 was considered significant. Results 37 patients with unilateral ovarian cysts were included. 12 (32%) resolved spontaneously prenatally, 14 (38%) resolved spontaneously postnatally, 5 (14%) underwent surgery postnatally and 6 (16%) cases underwent torsion. Rate of torsion increased with size from 0% (n = 0) in cysts ≤ 20 mm to 33% (n = 2) in cysts > 50 mm, however, the overall trend failed to reach statistical significance (P = 0.1). Cysts of 0-40 mm had a significantly higher rate of spontaneous resolution (90% vs. 44% in > 40 mm, P = 0.003), but the rate of torsion was not significantly different (10% in 0-40 mm vs. 25% in > 40 mm, P = 0.26). The median time to postnatal resolution was 10 (5–27) weeks in those treated conservatively. Conclusion Cysts > 40 mm are significantly less likely to resolve spontaneously, however torsion showed no significant correlation with cyst size. No complications were observed in cysts < 20 mm. Level of Evidence. IV, case series with no comparison group.
A retrospective multicenter study of the natural history of fetal ovarian cysts
Athanasios Tyraskis1, Spyros Bakalis2, Carolina Scala3, Argyro Syngelaki4, Stefano Giuliani5, Mark
Davenport1, Anna L. David2, Kypros Nicolaides4, Simon Eaton6, Paolo De Coppi6
1. Paediatric Surgery Unit, King’s College Hospital, London, UK
2. Institute for Women’s Health, University College London, UK
3. Fetal Medicine Unit, St. George’s Hospital, London, UK
4. Harris Birthright Centre, King’s College Hospital, London, UK
5. Department of Paediatric and Neonatal Surgery, St. George’s University Hospitals NHS Foundation
Trust, Blackshaw Rd, SW17 0QT, London, UK
6. Stem Cells and Regenerative Medicine, DBC, UCL Institute of Child Health and Great Ormond Street
Hospital London, UK
Corresponding Author:
Paolo De Coppi, MD, PhD
NIHR Professor and Consultant Paediatric Surgeon
Head of Stem Cells & Regenerative Medicine Section
Developmental Biology& Cancer Programme
UCL Great Ormond Street Institute of Child Health
30 Guilford Street
London WC1N 1EH
Tel: 020 7905 2641
p.decoppi@ucl.ac.uk
Abstract
Aim: We investigated the natural history of prenatally diagnosed ovarian cysts to estimate the risk of
torsion for cysts according to their size and sonographic appearance.
Methods: Cases of fetal ovarian cysts were identified at three tertiary fetal medicine units from January
2000 until January 2015. Data were collected on cyst size and pre- and postnatal sonographic features
until an outcome of either pre- or postnatal aspiration, surgery, torsion, or resolution of the cyst
resulted. In those where the cyst resolved, we identified subsequent scans to monitor for torsion and
absence of the ovary. Continuous data was reported as median and inter quartile range, Fishers exact
test was used to test differences between groups with 95% confidence intervals of proportions
reported, and logistic regression for the significance of size on the frequency of torsion.
Results: In the 15 year period 37 patients with unilateral ovarian cysts were included in this study, and
of these 12 (32%) resolved spontaneously prenatally, 14 (38%) resolved spontaneously postnatally, 5
(14%) girls underwent surgery postnatally and there were 6 (16%) cases of torsion. Lowest rate of
torsion was in cysts 0 - 20mm (n = 0, 0%), and increased with increasing size in cysts >50mm (n = 2, 33%)
although the overall trend failed to reach statistical significance (p = 0.1). Cysts of 0-40mm had a
significantly higher rate of spontaneous resolution without any invasive intervention (90% in cysts 0-
40mm vs. 44% in cysts >40mm, P = 0.003). However, the difference in the rate of torsion was not
statistically significant (10% in cysts 0-40mm vs. 25% in cysts >40mm, P = 0.26). The median number of
weeks to postnatal resolution was 10 (5 27) weeks in those treated conservatively.
Conclusion: Cysts >40mm in maximum diameter at the time of diagnosis are significantly less likely to
resolve spontaneously. No complications were observed in cysts < 20mm diameter, however torsion
showed no significant correlation with cyst size. Further studies are needed to clarify the role of prenatal
or postnatal aspiration of ovarian.
Type of study: Retrospective case series
Level of evidence: IV
Introduction
Follicular ovarian cysts in fetal life are a response to maternal and placental oestrogens and
gonadotrophins and occur as commonly as 1 in every 1,000 fetuses [1]. These cysts are often treated
conservatively prenatally and managed expectantly postnatally until resolution. There are increasing
data to suggest that there is a significant risk of ovarian torsion prenatally and that this risk is related to
the cyst diameter [2]. This has led some groups to attempt prenatal aspiration of cysts to decrease their
size and hopefully their chance of prenatal torsion. Most groups advocate a cut-off cyst diameter of 40
or 50mm as an indication for prenatal aspiration [3,4,5]. However, all previous studies have investigated
a single cyst size cut-off to determine the risk of torsion rather than describe the prevalence of torsion
according to cyst size.
The sonographic appearance of the cyst may also be significant in determining treatment strategy in
addition to its size. Simple cysts are assumed to be viable whereas complex cysts (especially if a fluid-
debris level is present internally) have a high likelihood of already having torted. Thus the simple cysts
would be the target of treatment in order to prevent ovarian loss [6.7].
Due to the rarity of large ovarian cysts and incomplete follow-up, the natural evolution of these cysts
has not been well studied, and the degree of risk of torsion with increasing cyst diameter has yet to be
quantified.
The aim of this study was to investigate the natural history of prenatally diagnosed ovarian cysts; to
estimate the risk of torsion for cysts according to their size and sonographic appearance, and to assess
likelihood of cyst resolution.
Method
This is a multicentre retrospective study of pregnant women referred to three tertiary-referral fetal
medicine units with follow-up of their infants in three pediatric surgery centres. Three fetal medicine
centres and their respective paediatric surgical centres were included in this study (King’s College
Hospital, St. Georges Hospital, University College London Hospital) with a further contribution from the
department of paediatric surgery at Great Ormond Street Hospital (the referral center for babies born at
University College London Hospital). Cases of fetal ovarian cysts were identified using the ViewPoint (GE
Healthcare, UK) ultrasound (US) database at each hospital. To ensure complete capture of fetal ovarian
cysts, a search for “ovarian or pelvic or abdominal cyst(s)” was performed on scans from January 2000
until January 2015. All identified cases were screened for eligibility where inclusion criteria were
unilateral or bilateral cyst(s) that were suspected to be of ovarian origin. Patients were excluded if they
were not followed up in one of the three fetal medicine centres, but rather had just been referred for a
second opinion and one ultrasound scan to ensure completeness of both prenatal and postnatal
information.
Data on cyst dimensions and sonographic appearance were gathered from all prenatal scans from time
of diagnosis until birth. Postnatal follow up data was obtained from all patients until the time of
resolution, aspiration or surgical excision. Any cases which during follow-up where determined to have
cysts of non-ovarian origin were excluded. The size measurements used to subdivide patients for the
subsequent analysis was the maximum diameter of the cyst at the time of the first prenatal US scan in
one of the three included tertiary fetal medicine centres. Median and interquartile range of cyst size
according to gestational age was reported and a subgroup analysis was performed according to the
maximum diameter on any prenatal US rather diagnosis. Patients who underwent prenatal aspiration
were included in the overall analysis and more information on their individual clinical course was
provided.
Ovarian loss in patients with ovarian cysts may occur due to torsion, and for the purpose of this study
was defined as: a necrotic ovary at the time of surgery, or a complex cyst which regressed without any
identifiable ovarian tissue on the ipsilateral side on more than one US scans post regression. Simple
cysts were defined as a thin-walled cyst with anechoic contents, and complex cysts included those with
internal septations, debris, or other echoic content which did not appear solid (solid complex cysts were
excluded due to the risk of being teratomas). Postnatal resolution was defined as resorption of the cyst
with two identifiable ovaries on US. Prenatal resolution was defined as resorption of the cyst on
subsequent antenatal US (most of these patients did not go on to have postnatal US).
This study was registered as an audit approved by the Clinical Audit and Safety Department of Great
Ormond Street Hospital (approval number: 1524) and therefore did not require formal ethical
committee approval.
Two-tailed Fisher’s exact tests were used to test for significant differences between the different size
groups, GraphPad Prism (Version 6) ® was used for this statistical analysis. 95% level of confidence was
defined as significant. Continuous data was reported as median and interquartile range. Overall trend
according to size was tested using a logistic regression on STATA 13 ®. Finally a 95% confidence interval
of proportion was calculated using the GraphPad Quick Calcs online software. A P value of <0.05 was
considered significant.
Results
A total of 109 patients were identified with a diagnosis of fetal ovarian cyst(s). 58/109 were referred to
our centres only for a second opinion, and had no further contact besides a single consultation. As we
did not have a complete data for follow-up and outcomes they were excluded from our study. 14 were
lost to follow-up either pre or postnatally, and the remaining 37 patients were included in the study
(Figure 1). Spontaneously resolution occurred in 12/37 (32%) cysts prior to birth, and 14 (38%) resolved
spontaneously after birth. Postnatal surgery occurred in 7 infants and 4 of those were found to have
torted necrotic ovaries and in 1 infant the ovary was twisted along the axis of the Fallopian tube but
was viable following detorsion and de-roofing. There were 6 cases of ovarian loss in total; 4 of those
were identified at the time of postnatal surgery and the remaining 2 had a complex cyst which regressed
without any remaining ovarian tissue on the ipsilateral side on multiple sonographic examinations
(ovarian loss in Figure 1).
The distribution according to size and frequency of outcomes can be seen in Table 1. Rates of torsion
increased incrementally from 0% for cysts 0-20mm, 14% (n = 1) in cysts 21-30mm, and 31-40mm, 20% (n
= 2) in cysts 41-50, and up to 33% (n = 2) in cysts >50mm at the time of diagnosis. Prenatal resolution
occurred less often with increasing size: 86% (n = 6) of cysts 0-20mm, 43% (n = 3) of those 21-40mm,
and 0% of those > 40mm. Of the cysts which remained postnatally, a similar decrease in spontaneous
resolutions was observed 75% (n = 7) of those 0-40mm, 50% (n = 5) of those 41-50mm, and 33% (n =
2) of those >50mm. No cyst <20mm underwent any invasive procedure, compared to 14% (n = 2) of
cysts 21-40mm, 40% (n = 4) of patients in the 41-50mm, and 50% (n = 3) of patients with cysts >50mm at
diagnosis. Interestingly, a significant difference is present when performing a subgroup analysis
comparing cysts of up to 40mm to those that were >40mm. Smaller cysts of 40mm resolved
spontaneously in 90% (n = 19) of cases compared to only 44% (n = 7) of cysts >40m (P = 0.003).
However, there was no significant difference in the rate of torsion of cysts 40mm, 10% (n = 2),
compared to 25% (n = 4) in cysts >40mm (P = 0.26). Of those cysts that resolved postnatally without
intervention, the median number of weeks to resolution was 10 with an interquartile range of 5 - 27
weeks.
Of relevance, diameters also change during the gestation with the median value for the largest diameter
of the cyst increasing from 19th to the 34th week of gestation after which we found that it plateaued
(Figure 2). At the time of diagnosis, 25 (68%) of the cysts were simple in sonographic appearance, 9
(24%) were complex, and for 3 (8%) the appearance was not commented on. Of the 25 that were simple,
18 (72%) resolved without any intervention, 8 prenatally and 10 postnatally. A total of 7 (28%) of the 25
simple cysts had an invasive procedure, 2 (8%) had a postnatal aspiration (and both subsequently
resolved), and 5 (20%) patients underwent operations (1 of which had already undergone a prenatal
aspiration), 2 (8%) had viable ovaries and 2 (8%) had torted necrotic ovaries. Of those 2 that were
necrotic, both had a complex appearance on the first postnatal ultrasound scan which was done in the
first week of life, and one of which had an auto-amputated cyst which was ‘wandering’ and was located
in the right upper quadrant of the abdomen on one scan.
Nine cysts were complex at the time of diagnosis, 3 (33%) underwent torsion, and 6 (67%) in total
resolved (4 prenatally and 2 postnatally). All four that resolved prenatally were < 40mm at the time of
diagnosis. One of the complex cysts which underwent torsion was 28mm at the time of diagnosis; the
other two were 54mm and 97mm. Three patients did not have the appearance of their cyst commented
on at the time of diagnosis. Two of those resolved postnatally and one had a repeat ultrasound a week
later prenatally and the cyst was found to be complex. Postnatally this patient had a laparoscopic
resection of a necrotic ovarian cyst that had undergone torsion.
Two prenatal aspirations were performed on the basis of their size. One cyst was simple, initially
measuring 64mm but growing to 102mm prenatally, occupying most of the fetal abdomen. 320mls of
straw coloured fluid was aspirated prenatally, however, this patient subsequently required surgical
deroofing due to re-accumulation of fluid postnatally, at which time the ovary was seen to be viable. The
second was a large complex cyst measuring 97mm at diagnosis and the decision was made to aspirate
due to signs of fetal anaemia at which time blood stained fluid was aspirated. The first postnatal
ultrasound and operation were performed in the first week of life and found the cyst to be in the
epigastric region. Subsequently this patient became symptomatic and a decision was made to operate,
and was found to have a necrotic ovary separate to the Fallopian tube of which only a remnant
remained (presumably following resorption of necrotic tissue), suggesting that the torsion had occurred
prenatally.
Postnatal aspiration was employed on two cysts, one measuring 45mm at diagnosis and one measuring
50mm at diagnosis. Both had grown 5-10mm after birth leading to the decision to aspirate. They had
good outcomes and these cysts went on to resolve completely within the first year of life.
Discussion
There is a paucity of actual evidence for the predictability of torsion of >40mm or >50mm ovarian cysts
which are often deemed as ‘large’ and at high risk of torsion according to a single size cutoff. [3, 8] Our
study is the largest case-series to date that describes the natural history of prenatally diagnosed ovarian
cysts according to a more detailed size categorization (multiple progressive size groups rather than two
groups based on an arbitrary cutoff). We found that cysts of <20mm in size had no adverse outcomes
nor did they require any postnatal intervention. Rates of torsion and surgery both increased with cyst
size but a logistic regression using the actual cyst measurements failed to show any significant
differences in the rate of torsion as cyst size increased (p = 0.1). This may be due to insufficient number
of cases in our study. Spontaneous resolution of the cysts also decreased consistently with increasing
cyst size. Although there was no clear cutoff for a size at which the risks of torsion or incidence of
surgery increased dramatically, our data indicated a increment in all outcomes (need for surgery, torsion
or failure to resolve spontaneously) for cysts of 40mm and greater. For this reason we did a subgroup
analysis comparing ovarian cysts measuring up to 40mm to those >40mm, the rates of spontaneous
resolution of the larger cysts were significant lower (44% vs. 90%, P < 0.01).
The timing of torsion in our cohort is not obvious but the clinical evidence points more to prenatal
torsion. Of the 6 cases of torsion in our study, 1 had an operation in the first week of life that only found
a cyst which was separate from a remnant of the fallopian tube indicating that the torsion had
undergone a significant period of time prior, only consistent with prenatal torsion. Of the remaining 5
patients, 3 of those had operations after the first week of life and the remaining 2 had a cyst which
resolved after the neonatal period with no ovary identifiable on repeated ultrasound scans, thus,
making it impossible to be certain regarding the timing of torsion. As none of these patients became
symptomatic postnatally, and 5 (83%) were complex on US prenatally with the last 1 having a complex
appearance on the first postnatal US in the first week of life, there is a strong suspicion that torsion
occurred prenatally. This finding could make an argument for prenatal aspiration [2], a technique still
rarely performed and utilised by us only in 2 cases.
Authors have supported the use of prenatal aspiration as a method of decreasing the risk of torsion in
larger cysts due to the assumed greater risk of torsion in those cysts. The size at which aspiration is
considered is 40-50mm depending on the study [2-3]. Encouraging results from one study using prenatal
aspiration show significantly decreased risk of torsion from 85% rate of torsion in cysts 50mm or larger
which were not aspirated to 14% in those which were [3]. Our study did not confirm that cysts larger
than 50mm had such high rates of torsion, nevertheless, larger prospective studies are necessary for
more accurate quantification of this risk, and the subsequent potential benefit of prenatal aspiration.
Postnatal aspiration was effective in both patients in which it was performed, however there is a paucity
of cases in the literature in order to corroborate its effectiveness. The infrequent reporting of postnatal
aspiration rather than surgery in the literature makes evaluating its outcomes particularly difficult. It is
dependent on the particular expertise being available and favorable positioning of the cyst with no
overlaying bowel to make safe aspiration possible. Some authors have employed it in 1-2 cases in their
larger cohorts of which one complication of intraperitoneal bleed has been noted [13]. Another caution
which other authors have emphasized is the re-accumulation of the cysts, one study observing this in 1
of 5 cases aspirated [6,8], a complication not occurring when surgical de-roofing or cystectomy is
performed [12].
Being complex in appearance is not a predictive risk factor for torsion but rather an indicator that there
has been a haemorrhagic process into the cyst. The cause can be benign such as a ruptured blood vessel,
or may represent a necrotic process leading to vessel disruption and bleeding into the cyst. All of our
cases that underwent torsion and necrosis were found to have a complex sonographic appearance prior
to the diagnosis of necrosis. One third of our cases that were complex had undergone torsion, slightly
lower than one of the largest studies in the literature; Galinier et al. found that of 55 haemorrhagic cysts
that 30 (55%) were either absent or unidentifiable on follow-up indicating ovarian loss [6].
Conclusion
Cysts in our study tended to increase in size until the 34th week of gestation. While this retrospective
study confirmed that size is a significant factor in the clinical evolution of fetal ovarian cysts, we showed
that cysts greater than 40mm, rather than 50mm as previously reported, are significantly less likely to
resolve spontaneously. Larger studies are needed to investigate if cysts greater than 40mm are at
significantly higher risk of torsion. Cysts less than 20mm in size are unlikely to have any complications.
Aspiration both pre and postnatally may provide a therapeutic option but clinicians must be aware of
risks of reaccumulation of fluid as well as that a complex sonographic appearance could be secondary to
both haemorrhage into an otherwise viable ovarian cyst or torsion and necrosis, and may represent
worse candidates for a therapeutic aspiration.
Acknowledgments
ALD is supported by the National Institute for Health Research University College London Hospitals
Biomedical Research Centre. PDC is supported by NIHR and the Great Ormond Street Hospital
Biomedical Research Centre and SE is supported by Great Ormond Street Hospital Biomedical Research
Centre and by Great Ormond Street Hospital Children’s Charity.
References
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ovarian cysts. J Pediat Surg 1991; 26: 276-282.
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Prenatal Diagnoais 2008; 28: 15-20.
Figure 1. Flowchart of outcomes for all patients.
Cysts identified (n = 109)
Follow-up in other center (n = 72)
Cysts included (n = 37)
Persisted postnatally Prenatal resolution Prenatal
aspiration
(n = 23) (n = 12) (n = 2)
Postnatal Ovarian Operated Postnatal Operated
Operated
resolution loss aspiration Prenatal
Viable
(n = 14) (n = 2) (n = 5) (n = 2) Torsion
(n = 1)
(n = 1)
Twisted (n = 4)
Necrotic Viable Resolved
Oophorectomy De-roofing (n = 2)
(n = 3) (n = 2)
Table 1. Table showing the outcomes of fetal ovarian cyst cases according to the cyst maximum
diameter at prenatal diagnosis.
Maximum
diameter at
diagnosis (mm)
Number of
cysts
Resolution
prenatally
Resolution
postnatally
Aspiration
(performed
prenatally)
Postnatal
surgery
Torsion
0-20
7
6
1
0
0
0
21-30
7
3
3
0
1
1
31-40
7
3
3
1
1
41-50
10
0
5
2 (0)
2
2
>50
6
0
2
3
2
Total
37
12
14
4 (2)
7
6
Table 2. Table of outcomes according to initial appearance of cyst on ultrasound.
Cyst
appearance on
ultrasound
Number of
cysts
Resolution
prenatally
Resolution
postnatally
Aspiration
(performed
prenatally)
Postnatal
surgery
Torsion
Simple
25
8
10
3 (1)
5
2
Complex
9
4
2
1 (1)
2
3
Unknown
3
0
2
0
0
1
Figure 2. The median and interquartile range values for maximum diameter according to the gestational
age of the patient when the US was performed.
... Cysts of ovarian origin are the most common intra-abdominal cyst detected in females perinatally [1]. These usually follicular cysts originate in foetal life as a response to maternal and placental oestrogens and gonadotrophins [2]. Postnatally hormonal levels decline in the neonates circulation and this is associated with a decrease in size in many antenatally diagnosed cysts, especially when they are simple in appearance [3]. ...
... When considering the size of the cyst, in our previous work we noted that cyst size was associated with the risk of torsion and chance of spontaneous resolution. Specifically, we found 40 mm of greatest diameter in the antenatal period to be associated with an increased risk of torsion and cyst smaller than 40 mm more likely to regress spontaneously [2,3]. In this study we also found that larger cysts of 60 mm had higher rates of ovarian salvage. ...
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Purpose To identify markers of previous ovarian torsion and outline the outcomes according to US appearance and operative management. Methods A retrospective single-centre review of neonatal ovarian cysts from January 2000 to January 2020. Data on postnatal cyst size and sonographic features and operative treatment were co-related with outcomes of ovarian loss and histology. Results 77 females were included with 22 simple and 56 complex cysts, one patient had bilateral cysts. 9/22 (41%) simple cysts regressed spontaneously in a median of 13 weeks (8–17). Complex cysts regressed spontaneously less frequently, 7/56(12%, P = 0.01), in 13 weeks (7–39). 38/56 (68%) complex and 12/22 (55%) simple cysts were treated operatively. 21/22 (95%) ovaries with initially simple cyst were salvaged compared to 20/56(36%) with initially complex cyst (P < 0.001). A fluid-debris level in 23/26 complex cysts was most associated with ovarian loss (P = 0.0006). Presence of viable ovarian stromal tissue was seen in 8/20 (40%) excised specimens during ovarian sparing procedures and in 5/30 (17%) oophorectomies for necrotic appearing ovaries. Conclusions Fluid-debris level on US is significantly associated with ovarian loss likely due to previous torsion. Simple cysts are viable and often regress spontaneously. The finding of viable ovarian stromal tissue in resected specimens supports attempting ovarian preservation wherever possible.
... Another extremely important ultrasonographic parameter, before establishing the therapeutic behavior, is their size. Most authors establish a cut-off of 20 mm as the minimum size for ovarian cyst diagnosis, with below this size being identified as the ovarian follicle [7]. Specific to ovarian cysts, the presence of a daughter cyst-a small, round structure with transonic content-has been described inside them [8,9]. ...
... The presence of complications of clinical symptoms, especially regarding complex cysts of increased size, require surgical treatment. Many authors propose surgical treatment when the size of the cyst is over 40 mm, even in the absence of symptoms due to the increased risk of complications [7,10]. ...
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Citation: Bucuri, C.; Mihu, D.; Malutan, A.; Oprea, V.; Berceanu, C.; Nati, I.; Rada, M.; Ormindean, C.; Blaga, L.; Ciortea, R. Fetal Ovarian Cyst-A Scoping Review of the Data from the Last 10 Years. Medicina 2023, 59, 186. https://doi. Abstract: Abdominal cystic masses are diagnosed during the intrauterine period and have a relatively low incidence. Fetal ovarian cysts are the most common form diagnosed prenatally or immediately after birth. The pathophysiology of the development of these types of tumors is not fully elucidated, with ovarian hyperstimulation caused by maternal and placental hormones being the most accepted hypothesis. During intrauterine development, the diagnosis of fetal ovarian cysts is most often made accidentally during usual checkup ultrasounds corresponding to the first, second, and third trimesters of pregnancy. We conducted a scoping review with the aim to map the current knowledge regarding the treatment of fetal ovarian cysts diagnosed in the intrauterine period. Focusing on the articles published in the last 10 years in the specialized literature, we tried to identify a conceptualization regarding the surveillance and treatment of these anomalies.
... Доля простых кист среди кист яичников у плода составляет, по данным разных авторов, от 20% до 68,4% [9, 11, 13,14]. В нашем исследовании простые кисты были представлены в большинстве случаев, их доля достигала 74,6%, практически не отличаясь от частоты, полученной нами ранее (71,4%) [15]. ...
... Появление в кисте сложной эхоструктуры считается признаком перекрута, риск которого повышается при больших размерах кисты [4,8]. Основными критериями, определяющими прогноз при кистах яичников, считаются их размеры и эхоструктура [13]. S. Manjiri et al. [17] описали исчезновение у новорожденных простых кист, размер которых не превышал 50 мм. ...
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I.V. Tihonenko Belarusian Medical Academy of Postgraduate Education, Minsk, Republic of Belarus Aim: to assess the outcomes of prenatally diagnosed ovarian cysts and to identify ultrasound features associated with the prognosis of surgical treatment. Patients and Methods: this retrospective study evaluated 59 fetal ovarian cysts diagnosed during ultrasound screening in the prenatal ultrasound center. The following parameters were reviewed: parity, maternal age, time of prenatal diagnosis, ultrasound cystic features and structure, and the outcomes of fetal ovarian cysts. Results: fetal ovarian cysts were detected during pregnancy in women with a median age of 30.6 years (17–42 years), 40.7% of them were primipara. A median gestational age at the date of prenatal cyst diagnosis was 33.5 (21.2–38) weeks of pregnancy. In 25.4% of cases the ovarian cysts had complex echotexture, and in 33.2% of cases a cyst diameter was ≥40 mm. In 32.2% of cases, the cysts were located at some distance from the bladder; 39% of the cysts were fully or partially visualized in the abdomen. The spontaneous cyst resolution by the time of delivery was reported in 37.3% of cases, including 40% of complex cysts. After birth, 35.6% of ovarian cysts disappeared and 20% of complex cysts demonstrated regression. Also, the regression occurred in 26.3% of cysts ≥ 40 mm. Overall, spontaneous resolution was reported for 60% of complex cysts, 42.1% of cysts ≥40 mm, 52.6% of cysts distinct from the bladder and 56.5% of cysts loca ted in the abdomen. Postnatal surgery was performed in 27.1% of the newborn girls. The likelihood of surgical treatment was higher in the newborns with prenatal cysts ≥ 40 mm comparing to cysts < 40 mm (odds ratio (OR), 7.78 (95% confidence interval (CI), 2.12–28.53)) and cysts located in the abdomen comparing to cysts located in the fetal pelvis (OR, 16.25 (95% CI, 3.84–68.82)). No correlation was found between ultrasound features of ovarian cysts and torsion. Conclusion: the ultrasound features of prenatally diagnosed ovarian cysts which are important for predicting a higher risk of postnatal surgical procedures include the cyst diameter (≥ 40 mm) and the location (especially in the abdomen). These factors should be taken into consideration for choosing a maternity hospital and prenatal consulting of parents. Keywords: fetal ovarian cyst, prenatal diagnosis, ultrasound features, outcome, prognosis. For citation: Tihonenko I.V. Ultrasound features of prenatally diagnosed ovarian cysts: what is important for the prognosis. Russian Journal of Woman and Child Health. 2022;5(4):287–291 (in Russ.). DOI: 10.32364/2618-8430-2022-5-4-287-291.
... Prenatal and postnatal management of ovarian cysts has not yet been standardized, although the prognosis is usually good. The indications for surgery depend on the center and are not always related to the prenatal findings 8,9 . ...
... There have been many reports on in utero aspiration of a fetal ovarian cyst to prevent ovarian torsion during pregnancy, but the efficacy of the procedure and the indications remain controversial [3,6,17,18]. Perhaps the earliest report on the efficacy of in utero aspiration evaluated in a large study was that by Bagolan et al. [3] They performed aspiration in cases with simple fetal ovarian cyst >50 mm and showed significant reductions in the rates of postnatal interventions, including oophorectomy. ...
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Aim: To investigate the natural history of fetal ovarian cysts and elucidate the risk factors for postnatal adverse outcomes in fetal ovarian cysts. Methods: The study subjects were 18 cases with ovarian cysts prenatally diagnosed using ultrasonography at our hospital between 2007 and 2020. The subjects were classified by cyst characteristics according to echogenic patterns [simple cyst (S) and complex cyst (C)], changes in echogenic patterns (S-to-S, S-to-C, and C-to-C), and diameters (<40 and ≥ 40 mm). Clinical parameters and outcomes were compared between S and C patterns, S-to-S and S-to-C patterns, and <40 and ≥ 40 mm diameters. Results: Cases with S and C patterns (15 and 3, respectively) had median gestational ages of 35 and 36 weeks, respectively, and maximum cyst diameters of 36 and 57mm, respectively. The number of cases with S-to-S, S-to-C and C-to-C patterns were 11, 4 and 3, respectively. The maximum cyst diameter in cases with S-to-C patterns (58 mm) was larger than that in cases with S-to-S patterns (34 mm) (P<0.05). Placental weight in cases with cysts >40 mm and/or cyst expansion was greater than that in cases with neither or both conditions (P<0.05). Spontaneous resolution (before and after birth) occurred in 8 of 9 and 3 of 9 cases with maximum cyst diameters <40 and ≥ 40 mm, respectively. Ovarian function was lost in 2 cases with S-to-C patterns and in 2 cases with C-to-C patterns. Conclusion: Cases with cyst diameters ≥ 40 mm and/or cyst expansion during the late third trimester had greater placental weight and more postnatal adverse outcomes.
... A multicentric retrospective study by Tyraskis et al. evaluated the risk of ovarian torsion in relationship to FOC size [40]. Their results showed that the rate of ovarian torsion increased from 0% in cysts measuring less than 20 mm to 33% in cysts measuring more than 50 mm, but they failed to demonstrate a statistically significant difference in this overall trend. ...
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Background and Objectives: Fetal ovarian cysts (FOCs) are a very rare pathology that can be associated with maternal–fetal and neonatal complications. The aim of this study was to assess the influence of ultrasound characteristics on FOC evolution and therapeutic management. Materials and Methods: We included cases admitted to our perinatal tertiary center between August 2016 and December 2022 with a prenatal or postnatal ultrasound evaluation indicative of FOC. We retrospectively analyzed the pre- and postnatal medical records, sonographic findings, operation protocols, and pathology reports. Results: This study investigated 20 cases of FOCs, of which 17 (85%) were diagnosed prenatally and 3 (15%) postnatally. The mean size of prenatally diagnosed ovarian cysts was 34.64 ± 12.53 mm for simple ovarian cysts and 55.16 ± 21.01 mm for complex ovarian cysts (p = 0.01). The simple FOCs ≤ 4 cm underwent resorption (n = 7, 70%) or size reduction (n = 3, 30%) without complications. Only 1 simple FOC greater than 4 cm reduced its size during follow-up, while 2 cases (66.6%) were complicated with ovarian torsion. Complex ovarian cysts diagnosed prenatally underwent resorption in only 1 case (25%), reduced in size in 1 case (25%), and were complicated with ovarian torsion in 2 cases (50%). Moreover, 2 simple (66.6%) and 1 complex (33.3%) fetal ovarian cysts were postnatally diagnosed. All of these simple ovarian cysts had a maximum diameter of ≤4 cm, and all of them underwent size reduction. The complex ovarian cyst of 4 cm underwent resorption during follow-up. Conclusions: Symptomatic neonatal ovarian cysts, as well as those that grow in size during sonographic follow-up, are in danger of ovarian torsion and should be operated on. Complex cysts and large cysts (with >4 cm diameter) could be followed up unless they become symptomatic or increase in dimensions during serial ultrasounds.
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Objective The prenatal diagnosis of fetal intra-abdominal cysts is challenging. This study aimed to evaluate the diagnostic ability of prenatal ultrasound for fetal intra-abdominal cysts and to develop a predictive method for pre- and postnatal outcomes. Methods We retrospectively reviewed fetuses with ultrasound-detected intra-abdominal cysts between January 2013 and January 2020. The maternal–fetal clinical characteristics and ultrasound parameters were integrated into a model of pre- or postnatal outcomes. Results The study enrolled 190 eligible fetuses, including 94 cases of spontaneous regression, 33 cases of conservative management and 63 cases of surgical intervention. For the 63 cases of surgical intervention, prenatal ultrasound was found to identify fetal intra-abdominal cysts with 80.00% sensitivity (95% CI: 67.03%–89.57%), 37.50% specificity (95% CI: 8.52%–75.51%), 89.80% positive predictive value (95% CI: 83.51%–93.86%), 21.43% negative predictive value (95% CI: 8.80%–43.53%) and 74.60% accuracy (95% CI: 62.06%–84.73%). The predictive model of prenatal spontaneous regression was as follows: y = −3.291 + 0.083 × gestational age + 1.252 × initial diameter, with an area under the curve (AUC) of 0.819 (95% CI: 0.739–0.899) and an optimal cut-off value of 0.74. The large cyst diameter before delivery was an independent predictor of postnatal surgical intervention ( p < 0.001), with an AUC of 0.710 (95% CI: 0.625–0.794) and an optimal cut-off value of 3.35 cm. Conclusion Although ultrasound has a limited ability in the accurate diagnosis of fetal abdominal cysts, a simple method of measuring the diameter can predict fetal outcomes and identify the cases that may require surgical intervention or spontaneous regression.
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Ante- or neonatal ovarian cysts can be often diagnosed by routine ultrasonography. Small simple ovarian cysts, which can be followed with serial ultrasonography, usually resolve spontaneously. Large simple cysts and complicated cysts should undergo surgical treatment to reduce the potential for serious complications. Seventeen ovarian cysts were experienced between 1983 and 1997. Sixteen cases underwent surgical treatment at less than 1 month of age according to our protocols. In this report, we reviewed these cases for clinical presentation, ultrasound data, management, intraoperative findings, complications, and outcome. At operation, nine of them showed torsion, and seven of them showed necrotic changes. Only five of them was considered to fall into torsion by preoperative ultrasonography. In five cases whose blood flow could not improve after reduction of torsion, salpingo-oophorectomy was performed. We consider that small simple ovarian cysts under 4 cm in diameter can be observed carefully with serial ultrasonography. But, not only complicated ovarian cysts and simple cysts over 5 cm in diameter, but smaller cysts showing no decrease in size should be considered for surgical indication to rescue the ovarian tissue.
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Neonates who have ovarian torsion caused by an ovarian cyst often lose their ovary because the torsion and infarction occurred antenatally. Because ultrasound scan has been so effective in diagnosing ovarian cysts in utero, we have a better understanding of their natural history and can select appropriate cases for cyst decompression in utero to prevent torsion. The authors reviewed experience with seven fetuses who had fetal ovarian cyst. During a 26-month period, seven patients were referred for the evaluation of fetal ovarian cyst. The mean gestational age at presentation was 31.9 +/- 3.6 weeks (+/-SD; range, 27 to 37 weeks). There was no history of maternal risk factors such as diabetes mellitus or fetal risk factors such as hyperthyroidism or placentomegally. All seven cases involved isolated unilateral cysts without associated anomalies or chromosomal abnormalities. Mean initial cyst diameter was 3.4 +/- 1.7 cm (+/-SD; range, 1 to 6.1). Indications used for ovarian cyst decompression included anechoic cysts with a diameter > or =4 cm, a cyst "wandering" about the abdomen on serial sonograms, or demonstrating rapid enlargement (>1 cm/wk). All but one cyst progressed in size during observation. One fetal ovarian cyst (diameter, 2 cm) subsequently regressed spontaneously and another (diameter, 2.1 cm) stabilized during prenatal ultrasound surveillance. One "cyst" observed with a diameter of 3.5 cm proved to be a persistent cloaca. Four fetal ovarian cysts met criteria for decompression. Because of fetal position, decompression could not be performed in one. One cyst (seen before defining criteria for decompression) with a diameter of 5 cm was observed only and underwent torsion. Two cysts (diameters, 6.1 cm and 4 cm) were decompressed in utero under local anesthesia with ultrasound guidance, of 95 mL and 35 mL, respectively. High cyst fluid progesterone (12,041 and 1,990 ng/dL, respectively) and testosterone (1,298 and 2,900 ng/dL, respectively) confirmed the etiology of the cyst as ovarian. Neither cyst recurred, and postnatal ultrasound scan confirmed resolution. There was no maternal or fetal morbidity or mortality and only the patient observed before development of criteria for decompression lost her ovary because of torsion. Fetal ovarian cysts tend to present as isolated unilateral lesions in normal fetuses in the third trimester. Spontaneous regression of fetal ovarian cysts may occur. Fetal ovarian cyst decompression, in select cases, may preserve ovaries at risk for torsion.
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Twenty-seven neonatal ovarian cysts were diagnosed in utero during a 13-year period; 9 were complicated and 18 were initially simple, but 8/18 showed evidence of complications in utero or soon after birth, leaving only 10 simple cysts. One simple and 4 complicated cysts were surgically excised early in the study period; 2 simple cysts were treated by needle aspiration at birth because of their large size. The remaining 20 cases were initially managed conservatively. All simple cysts and 10/13 complicated cysts regressed completely within 12 months; 3 that failed to regress were surgically excised. Nineteen patients who did not undergo a laparotomy had ultrasonographic (US) examinations from 3 months to 9 years after birth. Echography showed both ovaries in all 9 girls who had simple cysts at birth and in 2 of the 10 with complications. In the other 8 complicated cases only one ovary was detected at follow-up. Pre- or post-natal aspiration of simple cysts 4 cm or more in diameter is recommended, while conservative management seems appropriate in the absence of symptoms for simple cysts of less than 4 cm and complicated cysts of any size tending to involute after birth.
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Ovarian torsion causing the loss of an ovary represents the most common complication of fetal ovarian cysts and occurs more frequently before than after birth. Thus, treatment of fetal simple ovarian cysts should be performed antenatally; however, criteria for prenatal decompression still need to be evaluated. Previous experience of the authors showed that large simple cysts have a poor outcome, whereas preliminary attempts of their "in utero" aspiration were all successful and uneventful. The authors evaluated the outcome of fetal simple ovarian cysts after prenatal aspiration and considered criteria for this procedure. The outcome of cysts showing a prenatal ultrasound pattern of torsion also was studied. This prospective study includes 73 ovarian cysts (48 simple, 25 showing torsion) diagnosed in 72 fetuses from June 1992 to June 1999, and followed up until spontaneous resolution or surgery. Prenatal aspiration was performed in the case of simple cysts >/=5 cm in diameter. The outcome of these cysts was compared with that of similar cysts not aspirated in the authors previous study (X(2). Cysts with an US pattern of torsion persisting at birth were operated on. The outcome of simple cysts less than 5 cm and cysts with a prenatal ultrasound appearance of torsion also was evaluated. Prenatal decompression was performed without any complications in 14 cases: 12 (86%; 95% CI: 0.68 to 1.00) regressed subsequently; 2 (14%; 95% CI: 0.00 to 0.32) showed torsion postnatally. This outcome is significantly better than that of similar cysts not aspirated in the authors' previous study(10) (P =.0002). Among the 34 simple cysts less than 5 cm, 26 (76%; 95% CI: 0.62 to 0.90) resolved spontaneously; 8 (24%; 95% CI: 0.10 to 0.38) had complications, 7 of which showing torsion (diameter at evidence of torsion, 4.4 cm [median]; range, 3.3 to 5.2 cm). Among the 34 cysts showing torsion (25 with initial US pattern of torsion + 9 subsequently complicated simple cysts), 24 (71%; 95% CI: 0.56 to 0.86) required oophorectomy; 9 (26%; 95% CI: 0.11 to 0.41) spontaneously disappeared at ultrasound, one of which required surgery for intestinal obstruction secondary to adhesion of a necrotic ovary; one patient (3%; 95% CI: 0.00 to 0.09) was lost to follow-up. Prenatal aspiration of ovarian cysts appears effective and safe: a "cutoff" of 4 cm should be investigated. Cysts with ultrasound pattern of torsion persisting postnatally require surgery; options for their management, when sonographically disappearing and asymptomatic, need to be investigated.