Fetal choroid plexus cysts in the second trimester of pregnancy: a cause for concern

Ultrasound screening: Status of markers and efficacy of screening for structural abnormalities

Aneuploidy is a major cause of perinatal morbidity and mortality and can have a significant impact on expecting parents and their families. With early screening and diagnosis it is important to be able to educate parents regarding the potential impact of the diagnosis. This knowledge allows parents the opportunity to consider management options early in the pregnancy, permitting more time to mentally and emotionally prepare both for the course of the pregnancy, and after the birth of the child should the pregnancy continue. Prenatal screening provides pregnant women a non-invasive risk assessment for the most common aneuploidies. Those who are considered "high-risk" then have the option for additional diagnostic (invasive) testing. Prior to the 1980s, prenatal screening consisted of risk assessment through maternal age; however, with the advent of maternal serum biochemical analysis and ultrasound, the field of prenatal screening developed significantly. As biochemical and sonographic advances continued into the 1990s, the emphasis shifted to risk assessment in the first trimester, with the combination of maternal serum analytes and sonographic evaluation of the nuchal translucency.(1) Within the last decade, the introduction of non-invasive screening (NIPT/S) has shown great impact on the expansion and evolving practice of prenatal screening. Although in many places the standard for prenatal testing continues to include maternal serum analytes and sonographic evaluation, the role of each marker alone and in combination remains important. In the era of increasingly available screening tests, especially with NIPT/(NIPS), this article attempts to review the current role of ultrasound in prenatal care and elucidate the role of ultrasound markers in prenatal screening.

Parental level of anxiety, sense of coherence and state of mind when choroid plexus cysts have been identified at a routine ultrasound examination in the second trimester of pregnancy: a case control study

The aim of the study was to compare parents' experience of a routine ultrasound examination in the second trimester, when a choroid plexus cyst/cysts (CPC) were found (Study group; n = 22), with matched controls where no fetal deviations were identified (Control group, n = 66). All the parents had participated in a larger cohort study. The instruments used for measuring anxiety were STAI-state/trait, sense of coherence (SOC) and Parents' Expectations, Experiences, Reactions to an Ultrasound examination during pregnancy (PEER-U, State of Mind Index). Regarding the SOC and STAI-state/trait no significant differences were found between the cases and controls or within the respective group before and after the ultrasound examination. The cases had an increase in anxiety (more anxious) as measured by the instrument PEER-U after the examination, while the controls showed a significant better level of State of Mind Index (less anxious) after the examination, compared to before. Therefore PEER-U can be a more reliable instrument when studying state of mind (anxiety) in connection with ultrasound examinations, and as it is specific for this situation it does not appear to be time dependent.

Information for better or for worse: interviews with parents when their foetus was found to have choroid plexus cysts at a routine second trimester ultrasound

The aim of the study was to gain a theoretical understanding of parents' experiences and handling of the situation, when their foetus was diagnosed as having choroid plexus cysts, at a routine second trimester ultrasound examination. Nine couples and one mother were interviewed using one open question. Analysis method was Grounded Theory. The main concern was anxiety and the core category became need for knowledge. The other categories were frightening and confusing, judging risk and making a choice and comforting. The parents felt information during the ultrasound examination was insufficient. The time delay between the diagnosis and the doctor's appointment was also often criticized. Most of the parents in this study wanted to know what can be diagnosed by ultrasound, even if there is a small risk that the child will have a malformation or chromosome abnormality. However, when the diagnosis is made, they need adequate information, otherwise unnecessary anxiety arises. By giving sufficient information without days of delay, anxiety can hopefully be minimized. Some written information was also requested. It is of utmost importance that the staff use the same terminology and the correct name of the soft marker to the parents.

Isolated choroid plexus cyst or echogenic cardiac focus on prenatal ultrasound: is genetic amniocentesis indicated?

OBJECTIVE

The purpose of this study was to determine whether or not genetic amniocentesis is warranted when isolated choroid plexus cysts (CPC) or echogenic cardiac foci (EF) are noted on prenatal ultrasound.

STUDY DESIGN

We performed a retrospective analysis on patients from our perinatal database. All obstetric patients with CPC or EF noted on second-trimester perinatology ultrasound from April, 1998 to November, 2004 were included. Information regarding ultrasound findings and neonatal outcome were analyzed.

RESULTS

During the study period, 515 patients with CPC or EF were evaluated. Of these, 429 (83.3%) had isolated CPC or EF and 86 (16.7%) had additional risk factors. The incidence of abnormal karyotype was 0 versus 2.3%, respectively (P = .03). The additional risk factors considered were: advanced maternal age, abnormal serum triple marker screening, and/or other abnormal ultrasound findings. Furthermore, during the study period there were 20,122 live births and 27 (0.1%) cases of aneuploidy diagnosed postnatally. Of these, none had isolated CPC or EF on prenatal ultrasound.

CONCLUSION

CPC or EF noted on prenatal ultrasound warrants referral for careful consultative ultrasound evaluation. In the absence of other risk factors, however, genetic amniocentesis for isolated CPC or EF does not appear to be necessary.

Developmental outcome of children who had choroid plexus cysts detected prenatally

OBJECTIVE

The purpose of this study was to evaluate cognitive, motor, language and adaptive behavior development in children who had isolated choroid plexus cysts (CPC) detected prenatally.

METHODS

A retrospective double cohort design and standardized psychometric measures were used to compare the development of children who had isolated CPCs identified prenatally with a control group of children who had normal prenatal ultrasounds.

RESULTS

Our study cohort (n = 37) had a mean age of 3.88 years (SD = 0.83) and the control cohort (n = 48) had a mean age of 4.62 years (SD = 1.03). The age difference between our cohorts was significant. There were no differences between cohorts in socioeconomic status, sex, birth weight or gestational age. Cognitive data showed no clinically significant difference in Full Scale IQ using the WISC-III or WPPSI-R (CPC = 113.97, control = 116.69). Scores on standardized measures of motor and adaptive functioning also did not show any significant group differences. Children with CPCs did score significantly lower than controls on some of the measures of verbal functioning; however, this difference was not associated with clinically significant delays.

CONCLUSION

We conclude that the presence of isolated CPCs on midtrimester ultrasound are unlikely to be associated with any significant neurocognitive delays in early childhood.

Isolated choroid plexus cyst in low-risk women less than 35 years old

OBJECTIVE

The purpose of this study was to determine the incidence of trisomy 18 in women who are <35 years old and who have sonographically detected isolated choroid plexus cyst.

STUDY DESIGN

A meta-analysis of prospective trials that were published in the English language between 1990 and 2000 was performed. Each trial met the following inclusion criteria: (1) prospective trial, (2) total population screened during the study period reported, (3) maternal age (either numeric or descriptive) reported, and (4) pregnancy/neonatal outcomes reported. An isolated choroid plexus cyst for the purpose of this study was defined as absence of sonographically detected structural abnormalities and normal serum analyte screens, if reported.

RESULTS

Eight trials met the criteria and were used for analysis. A total of 106,732 women were screened through articles that were published between 1990 and 2000. The total number of fetuses with choroid plexus cysts that were identified in second-trimester scans were 1,235 (incidence, 1.2%). The incidence of isolated choroid plexus cysts in women who were <35 years old was 1.0% (n = 1,017 women). There were no cases of trisomy 18 in women with isolated choroid plexus cyst who were <35 years old. Four structural abnormalities were noted on postnatal examination; all four neonates had normal karyotypes.

CONCLUSION

There is no evidence that detection of isolated choroid plexus cyst in women who are <35 years of age increases the risk of trisomy 18. Therefore, amniocentesis is not warranted because of the inherent risk of pregnancy loss that is associated with the procedure. Better algorithms are needed to screen women who have a low risk for trisomy 18.

Choroid plexus cysts in the mid-trimester fetus--practical application suggests superiority of an individualized risk method of counseling for trisomy 18

OBJECTIVES

Analysis of a referral population of patients with choroid plexus cysts (CPCs) was performed to compare an average risk method of counseling to an individualized risk method.

METHODS

A total of 395 patients referred to a Prenatal Diagnosis Center were included, of whom 341 had isolated CPCs and 54 had associated ultrasound abnormalities. For isolated CPCs, an average risk of 1/150 for aneuploidy was compared to an individualized risk assessment [prior risk as determined by maternal age or serum screening multiplied by the likelihood ratio established by Gupta et al. (1997)]. Accuracy, cost, and procedure-related losses were assessed.

RESULTS

Both methods resulted in 100% sensitivity. The individualized method resulted in greater specificity, decreased costs, and (theoretically) fewer procedure-related pregnancy losses.

CONCLUSIONS

An individualized risk method of counseling utilizing the likelihood ratios established by Gupta et al. (1997) was superior to an average risk method for assessing trisomy 18 risk in the setting of CPC detected in mid-trimester.

Parental decision-making differences between patients in two healthcare systems for choroid plexus cysts

We evaluated the medical-sociological implications of parental perception of risk and decision-making choices for prenatally ascertained choroid plexus cysts (CPC) between two obstetric populations. The Wayne State University (WSU) Reproductive Genetics database and the Madigan Army Medical Center (MAMC) experience were reviewed to compare the rates of aneuploidy and invasive testing for cases with CPC. Aneuploidy rates were compared between those with isolated CPC, CPC with advanced maternal age (AMA), and CPC associated with multiple anomalies. In the WSU cohort 186 cases were identified, of whom 27 (15%) declined invasive fetal testing. In the remaining 159 cases, aneuploidy was present in 2/132 (1.5%) isolated CPC, 3/11 (27%) CPC with AMA, and 15/16 (93%) CPC with multiple anomalies. In the MAMC cohort 107 cases were identified, of whom 99 (92%) declined invasive fetal testing. No aneuploidy cases were found in the 3/12 AMA cases or 5/95 non-AMA cases that underwent amniocentesis. The two cases of aneuploidy with isolated CPC cannot be ignored, and provide an estimated attributable risk of at least 0.8%, a higher risk than 38 years of age. However, the parental sociologic context may be as important for decision-making as the genetic-prognostic risk.

Second trimester markers of aneuploidy

The risks of aneuploidy associated with identification of a sonographic marker in the low risk population is controversial. Prior risk estimates have been derived usually from high risk populations. Screening programmes in the first trimester, second trimester and combined first and second trimester will undoubtedly alter the second trimester scan as a screening tool for aneuploidy. This chapter reviews the current sonographic markers and the difficulties in their application to the general population.

Prenatal ultrasound findings in affected and unaffected pregnancies that are screen-positive for trisomy 18: the California experience

This study investigated whether significant differences in ultrasound findings exist between trisomy 18 affected and unaffected pregnancies positive by serum screening. Ultrasound reports were reviewed for 335 screen-positive women. This represented 65% of all trisomy 18 screen-positive patients who had follow-up services at any of 117 Californian state-approved Prenatal Diagnosis Centers during a six-month period from November 1, 1995 to April 30, 1996. Ultrasound reports were available for 100% of trisomy 18 fetuses diagnosed during the six month period (n=23). Ultrasound findings were reported as normal in 35% of the fetuses affected with trisomy 18. The number and type of abnormalities observed in the affected and unaffected groups are described. When compared to unaffected cases, the trisomy 18 affected fetuses had a greater re-dating discrepancy on follow-up ultrasound evaluation and significantly lower femur length to biparietal diameter (FL/BPD) ratio measurements. We recommend that all women who are screen positive for trisomy 18 be encouraged to have amniocentesis, regardless of ultrasound findings, since affected fetuses may not be detected otherwise.

Isolated fetal choroid plexus cysts: role of ultrasonography in establishment of the risk of trisomy 18

OBJECTIVE

The significance of isolated choroid plexus cysts found by ultrasonographic scan during the second trimester as a marker for trisomy 18 is still debated. We analyzed our data and reviewed the series published in the English-language literature to calculate the likelihood ratio of trisomy 18 in the presence of isolated choroid plexus cysts; that is, the factor by which the individual risk of trisomy 18 is increased in the presence of isolated choroid plexus cysts.

STUDY DESIGN

Likelihood ratios were calculated as ratio of the sensitivity to the false-positive rate. Sensitivity was defined as the rate of isolated choroid plexus cysts detected at midgestation among fetuses with trisomy 18. False-positive rate was defined as the rate of choroid plexus cysts detected at midgestation in the population without trisomy 18. The sensitivities of all published series reporting rates of choroid plexus cysts at the time of the first ultrasonographic examination between 14 and 24 weeks' gestation in populations with trisomy 18 and in low-risk populations were included in the analysis. To these we added all cases of trisomy 18 diagnosed at our institution during the period January 1, 1988, through June 30, 1998, in which prenatal ultrasonographic examination was performed between 14 and 24 weeks' gestation.

RESULTS

The prevalence of second-trimester ultrasonographic detection of isolated choroid plexus cysts among fetuses with trisomy 18 was 6.7% (13/194), whereas that in the population without trisomy 18 was 0.9% (752/79,583). The likelihood ratio associated with isolated choroid plexus cysts was therefore 7.09 (95% confidence interval, 3.97-12.18).

CONCLUSION

The presence of isolated second-trimester choroid plexus cysts increases the base risk of trisomy 18 by a factor of 7.09. This likelihood ratio can be multiplied by the risk calculated according to maternal age to obtain the individual risk of trisomy 18 and thus permit more accurate counseling of the patient.

Screening for chromosomal abnormality

Screening for fetal abnormalities has become one of the most high profile health care issues of modern times. This issue is predicated on major advances in health care technology that permit wider detection of fetal anomalies, including the development of more advanced biochemical markers and improvements in ultrasound imaging. The effectiveness of these screening methods and their rational application is a point of great controversy, and is the cause of considerable unease in clinical obstetrical practice. This article reviews the general concepts of fetal screening for fetal chromosome abnormalities and then focuses on certain aspects of ultrasound screening that are particularly controversial. The scientific basis for each ultrasound finding (e.g., nuchal translucency) is reviewed, as well as the frequently divergent clinical experience with the finding. Finally, a plea is made for the development of a more scientific database for fetal ultrasound screening, and the setting of fetal screening guidelines for practicing physicians based on diagnostic accuracy and cost-effectiveness.

Choroid plexus cysts and aneuploidy

The association of choroid plexus cysts with fetal aneuploidy, particularly trisomy 18, was first noted in 1986. Through the years there have been numerous reports on this subject, but no consensus has been reached with regard to chromosomal risk. In this review, we attempt to summarise published reports on second trimester choroid plexus cysts, with an emphasis on the strengths and weaknesses of each report. Based on these reports, additional malformations are a significant risk factor for aneuploidy and an indication for determination of fetal karyotype. The management of isolated choroid plexus cysts remains controversial.

Choroid plexus cysts--association with trisomy: prospective review of 16,059 patients

OBJECTIVE

The purpose of the study was to determine the incidence of isolated choroid plexus cysts in association with trisomy 18 and other abnormalities.

STUDY DESIGN

All patients from June 1992 through December 1995 were followed up after a screening ultrasonography. Any patient with a choroid plexus cyst was offered genetic counseling and an amniocentesis. Screening ultrasonographic examinations were performed on 16,059 patients, and 301 patients had a fetus with a choroid plexus cyst. One hundred thirty patients elected to have an amniocentesis. Patients were followed up to delivery.

RESULTS

Two hundred sixty-three patients had an isolated choroid plexus cyst. Thirty-eight patients had a choroid plexus cyst associated with additional risk factors. Risk factors included advanced maternal age, additional ultrasonographic abnormalities, past obstetric history, or family history. No abnormalities were noted in the group with an isolated choroid plexus cyst. Four patients had an abnormality when the choroid plexus cyst was associated with an additional risk factor, including two patients with trisomy 18 and one with trisomy 21.

CONCLUSION

An isolated choroid plexus cyst was not associated with a trisomy or other abnormalities in this study. When a choroid plexus cyst was associated with an additional risk factor, 10.5% of the patients had an abnormality. Amniocentesis is recommended when a choroid plexus cyst is found in association with additional risk factors.

Clinical significance of fetal choroid plexus cysts

Choroid plexus (CP) cysts are commonly detected on routine mid-trimester ultrasound scan. When associated anomalies are detected, the risk is sufficient to justify an invasive diagnostic test such as amniocentesis. However, the risk when no associated anomalies are detected is much less well defined. This information is required to determine the appropriate management in cases of apparently isolated CP cysts. We thought the only way to resolve the difficulties in counselling prospective parents was to conduct a prospective study in a large unselected population. A registry of fetal CP cysts detected over 3 years in the Yorkshire Region was compiled and we identified 524 CP cysts. These cases were then amalgamated and analysed with 1361 cases from prospective studies reported in the world English literature and a further 71 unpublished cases identified from a 2 year prospective series from Ninewells Hospital, Dundee. The risk of chromosomal abnormalities was 1 in 150 (95% CI 1 in 85, 1 in 261) when no fetal anatomic abnormalities, apart from the CP cysts themselves, were detected antenatally. The risk increased to approximately 1 in 3 if any other associated ultrasound abnormalities were detected antenatally. The risk did not appear to be related to whether or not cyst size diminished as gestation progresses, whether they were unilateral or bilateral, and whether they were small or large in size (60-80% < 10 mm). 76% of aneuploidic cases were trisomy 18 and 17% were trisomy 21. The risk of Down's syndrome in fetuses with CP cysts but no other anomalies detected antenatally is 1 in 880. The probability of a chromosomal abnormality is high when CP cysts are associated with any other antenatally detected anomaly, indicating a clear need to offering amniocentesis. The predictive value is much lower when no other anomalies are detected. In such cases, it is probably advisable to regard CP cysts as an indication for detailed ultrasound assessment, rather than invasive testing.

Isolated fetal choroid plexus cysts and trisomy 18: a review and meta-analysis

OBJECTIVE

Risk of trisomy 18 in a fetus with ultrasonographic diagnosis of choroid plexus cysts and no other anomalies is controversial. Using our data and current literature, we performed a meta-analysis and estimated the positive predictive value of isolated choroid plexus cysts for trisomy 18.

STUDY DESIGN

Between Jan. 1, 1989, and Dec. 31, 1992, all women undergoing ultrasonographic examination at our institution were prospectively evaluated for fetal choroid plexus cysts and cytogenetic outcome. In addition, all reports dealing with fetal choroid plexus cysts obtained from MEDLINE (1983 through 1992) were assessed. Only prospective studies with > 10 cases of choroid plexus cysts were further evaluated to determine the total number of fetuses with choroid plexus cysts and otherwise normal sonograms. Frequency of aneuploidy was determined by analysis of our data and the included studies. To estimate the positive predictive value of choroid plexus cysts from trisomy 18, a theoretic 2 x 2 table was constructed with values available from the literature.

RESULTS

Eighty fetuses with choroid plexus cysts were identified in our unit. Of 74 fetuses with isolated choroid plexus cysts, there were no cases of trisomy 18. Meta-analysis identified 2 cases of trisomy 18 among 748 fetuses with isolated cysts (1/374). To derive a positive predictive value of isolated choroid plexus cysts for trisomy 18, we reviewed the literature and found a total of 50 fetuses with trisomy 18 who underwent ultrasonographic examination in the midtrimester. There were 3 cases of isolated choroid plexus cysts, and 12 of 50 (24%) had otherwise normal ultrasonographic results. Using a midtrimester incidence of 1 in 2461 for trisomy 18 (Hsu LYF. In: Milunsky A, ed. Genetic disorders of the fetus. 3rd ed. Baltimore: Johns Hopkins University Press, 1992: 155-210; Hook et al. Am J Hum Genet 1989; 45:855-61) and a prenatal prevalence of 0.95% for choroid plexus cysts (based on a review of the literature), we obtained a positive predictive value of 1 in 390.

CONCLUSION

On the basis of the risk for trisomy 18 obtained from our meta-analysis (1/374) and its close approximation to the estimated positive predictive value (1/390), our data do not support the routine offering of invasive prenatal cytogenetic testing in cases of isolated choroid plexus cysts.

Fetal choroid plexus cysts and trisomy 18: assessment of risk based on ultrasound findings and maternal age

This paper examines the association between fetal choroid plexus cysts (CPCs) and trisomy 18 and proposes a method by which risks can be derived taking into account both sonographic findings and maternal age. Data from our centre on the sonographic findings of 58 fetuses with trisomy 18 and 387 fetuses with CPCs as well as data from published series were used. It was calculated that the prevalence of CPCs in the general population is approximately 1 per cent and at mid-gestation the incidence of CPCs in fetuses with trisomy 18 is approximately 50 per cent. In the 387 fetuses with CPCs, the incidence of trisomy 18 increased with maternal age and the likelihood ratio for trisomy 18 increased with the number of additional abnormalities, from 0.03 for those with isolated CPCs to 0.4 if there was one additional abnormality and 20.5 if there were two or more additional abnormalities. It was concluded that if the cysts are apparently isolated, the risk for trisomy 18 is only marginally increased and maternal age should be the main factor in deciding whether or not to offer fetal karyotyping. If one additional abnormality is found, the maternal age-related risk is increased, so that even for a 20-year-old the risk for trisomy 18 is at least as high as the risk for trisomy 21 in a 35-year-old. In this respect, it may be considered desirable to offer such patients the option of karyotyping.

Isolated choroid plexus cyst(s): an indication for amniocentesis

OBJECTIVE

Our purpose was to prospectively evaluate the risk of chromosomal abnormalities associated with isolated choroid plexus cyst(s) in gravid women undergoing second-trimester ultrasonographic examination.

STUDY DESIGN

During a 24-month period 9100 pregnant women underwent midtrimester ultrasonographic evaluation. Women with a fetal diagnosis of choroid plexus cyst(s) were offered amniocentesis and a repeat examination in 4 to 6 weeks.

RESULTS

A diagnosis of choroid plexus cyst(s) was made in 102 fetuses (1.1%). In four of these fetuses multiple congenital anomalies were noted. Three of the four fetuses had a chromosomal abnormality, two trisomy 18 and one unbalanced translocation, t(3;13). In the remaining 98 fetuses the choroid plexus cysts were isolated findings, that is, there were no other ultrasonographically detected anomalies. Seventy-five of these 98 fetuses underwent amniocentesis. An abnormal karyotype was identified in four fetuses: three had Down syndrome (two trisomy 21 and one unbalanced translocation, t[14;21]), and one trisomy 18. The offspring of the 23 patients in which amniocentesis was declined were phenotypically normal.

CONCLUSIONS

In our prospective study the risk of chromosomal abnormality with isolated choroid plexus cyst(s) was 1:25, a risk that exceeds the 1:200 risk of pregnancy loss after amniocentesis and the 1:126 and 1:260 risk for aneuploidy and Down syndrome, respectively, in a 35-year-old pregnant women during the midtrimester. These findings indicate that amniocentesis should be offered to pregnant women in the presence of isolated fetal choroid plexus cyst(s).

Isolated choroid plexus cysts--the need for routine offer of karyotyping

The management of isolated fetal choroid plexus cysts remains controversial. We have prospectively studied 15,565 pregnancies at two large obstetric units for the presence of choroid plexus cysts. In all cases where cysts were present at 19 weeks' gestation or greater, and were multiple, bilateral or solitary and greater than 5 mm maximum diameter, women were offered amniocentesis or placental biopsy, irrespective of the presence or absence of other abnormalities. Choroid plexus cysts were present in 152 (0.98 per cent) of cases. Four cases (2.6 per cent) of autosomal trisomy (three of trisomy 18, one of trisomy 21) were detected on prenatal karyotyping. In all cases, choroid plexus cysts were the only detectable prenatal anomaly. This study and a review of other large studies do not support the view that isolated choroid plexus cysts are a benign variant, the risk of trisomy being 1 in 82. Until further evidence is available, we recommend that cases of isolated fetal choroid plexus cysts at 19 weeks' gestation or greater should be offered prenatal karyotyping.

Fetal choroid plexus cysts in association with cri du chat (5p-) syndrome

The significance of fetal choroid plexus cysts is controversial. We report a case of antenatally detected cri du chat syndrome (5p-) in one fetus of a twin pregnancy in association with bilateral fetal choroid plexus cysts and unassociated with other structural malformations. Choroid plexus cysts may be nonspecific markers for chromosomal anomalies.

Choroid plexus cysts in the fetal brain

Choroid plexus cysts may be detected in the fetal choroid plexus on routine second trimester ultrasound scanning. The presence of these cysts is associated with trisomy 18 (Edward syndrome) in 3.47% of cases and with trisomy 21 (Down syndrome) in 0.46% of cases. The cysts themselves almost always disappear by 23 weeks and are thought to be a normal developmental variant. The world literature experience would indicate that the size of the choroid plexus cyst and the presence of bilateral cysts has no bearing on the magnitude of risk of chromosomal abnormality; 76% of babies with trisomy 18 also have other dysmorphic features which may be detectable by ultrasound. It is strongly advised that genetic counselling be undertaken and amniocentesis be considered when choroid plexus cysts are identified in the fetus.

Fetal choroid plexus cysts: an independent risk factor for chromosomal anomalies

As a result of numerous conflicting reports, we designed a prospective controlled study to determine the inherent risk of aneuploidy with second-trimester fetal choroid plexus cysts. Our controls were patients who had ultrasonography and genetic amniocentesis, between 15 weeks and 22 weeks, menstrual age, by the same sonologist on the same day as a study subject with a choroid plexus cyst. Sixty-three cases of fetal choroid plexus cysts were detected in 3247 second-trimester examinations (1.9%). Six chromosomally abnormal fetuses [Trisomy 18 (3), Down syndrome (2), Klinefelter syndrome] were found in the cyst group (9.5%) with only one Trisomy 21 among the controls (0.5%) (p < .002). Of note, 5 of 21 (23.8%) fetuses with cysts greater than 5 mm in diameter had aneuploidy, as compared with only 1 of 42 (2.4%) chromosomal anomalies with smaller cysts (p < .02). We conclude that fetal choroid plexus cysts are an independent risk factor for chromosomal anomalies; genetic counseling and prenatal chromosomal analysis are indicated.

Choroid plexus cysts: significance and current management practices

Choroid plexus cysts are commonly found in normal fetuses in the second trimester, but the presence of cysts is an indication for a targeted ultrasound scan for signs associated with aneuploidy. In this review the authors explain the histological basis for choroid plexus cyst formation, the association with aneuploidy, and the management controversies that continues to be debated in the literature.