Simon
J.
Ostlere,
MRCP,
FRCR
C. Irving,
#{149} Henry
FRCR
#{149} Richard
Lilford,
J.
MRCOG,
MRCP,
PhD
fetal
chonoid
Fetal Choroid Plexus Cysts: A Report of 100 Cases’ A prospective study was undertaken to evaluate the prevalence and significance of fetal choroid plexus cysts detected on screening ultrasound (US) scans. One hundred cases of fetal choroid plexus cysts were detected from 11,700 examinations: There were 95 healthy newborns, three newborns with trisomy 18, one newborn with syndactyly of the toes, and one intrauterine death. In the three neonates with trisomy 18 the cysts were large (>1 cm in diameter), and additional abnormalities were detected. Although there is a clear association between fetal choroid plexus cysts and trisomy 18, amniocentesis or chorionic villus sampling should be reserved for high-risk patients with either large cysts or US evidence of other abnormalities. Index terms: Choroid plexus, neoplasms, 1617.31, 1617.1842 #{149} Choroid plexus, US studies, 1617.1298 #{149} Fetus, abnormalities, 856.874 Fetus, US studies, 856.1298 #{149} Trisomy 18 Radiology
1990;
#{149}
175:753-755
30
U)
20
z U.
0 10 0
z
0.1
0.2
0.3
0.4
0.5
lflnnr. !
0.6
SIZE
Figure
1.
0.7
0.8
0.9
CYST
OF
Distribution
1
1.1
1.2
1.3
1.4
1.5
(CUS)
of maximum
ameter in fetuses with choroid . = trisomy 18, D normal.
cyst
plexus
di-
cysts. Figure cysts
C
within the fetal choroid plexus are occasionally detected at ultrasound (US) scanning of women in the second trimester of pregnancy. Although the vast majority of these cysts resolve spontaneously and are not associated with any morbidity, several reports in the literatune have indicated a possible association between fetal choroid plexus cysts and chromosomal abnormalities, principally trisomy 18. To evaluate accurately the prevalence and significance of fetal chonoid plexus cysts, we undertook a prospective study involving approximately 1 1,700 routine dating scans. The first
MATERIALS
AND
METHODS
At our institution routine antenatal ing scanning is performed at approximately 16-18 weeks gestation. During first From the Departments of Radiology (S.J.O., H.C.I.) and Obstetrics (R.J.L.), St James’s University Hospital, Leeds LS9 7TF, England. From the 1989 RSNA annual meeting. Received November 6, 1989; revision requested December 20;
revision
received
January 16. Address c RSNA, 1990
January
reprint
1 1, 1990;
requests
Bilateral
plexus
fetus.
YSTS
7,000 scans, including 42 cases of fetal choroid plexus cysts, are the subject of a previous report (1).
1
2.
in a healthy
24 months
of the
scanning was art equipment
performed
on
(Hitachi
EUB
Medical,
Tokyo],
study,
60%
3.5-MHz
accepted
3.5-MHz
months formed
linear
array).
the
of all
state-of-the-
340
[Hitachi
curvilinear
nay) and 40% on an older model fenior spatial resolution (Hitachi
to H.C.I.
dat-
During
of the study all scanning on the Hitachi EUB 340.
an-
with inEUB 25, the
last
6
was perAll ex-
aminations included careful inspection of the choroid plexuses. All scans were necorded on photographic film and reviewed by a senior sonognaphen. When choroid plexus cysts were detected, follow-up scans were arranged at approximately 26 weeks. Further scans were obtamed if the cysts had not resolved or if other abnormalities were detected. All newborns underwent routine postnatal clinical examination. ysis was reserved
whom clinically
for
chromosomal
Chromosornal those neonates
abnormalities
analin
were
suspected.
RESULTS One hundred cases of fetal choroid plexus cysts were detected among the estimated 1 1,700 scans obtained oven a 21h-year period. Scans obtained with the newer Hitachi EUB 340 equipment showed fetal choroid plexus cysts in one of 90 pregnancies, compared with one of 300 when the older Hitachi EUB 25 was used. The cysts were bilateral in 52 fetuses, unilateral and multiple in six, and solitary in 42. When the long axis of the fetal head was perpendicular to the scan plane, 75% of the solitary cysts were detected in the plexus farthest from the scanning probe. The cysts varied considerably in size and shape 753
Table
1
Three
Cases
of Trisomy
18 with
Case
Cyst Size (cm)
Gestational Age (wk)
Location of Cysts
1
20
Bilateral
1
Choroid
Plexus
Follow-up 26 wk:
Cysts Additional Sonographic Findings
Findings
cysts
mal neonatal
resolved, head
nor-
Ventniculoseptal
scan
intrauterine
defect,
growth
re-
tardation
2
1.5
19.5
Bilateral
25 wk: cysts still present 31 wk: cysts resolved, normal neonatal head scan
Bilateral hydronephrosis, polyhydramnios, intrauterine growth retarda-
3
1.5
17
Bilateral
18 wk: 21 wk:
Diaphragmatic
tion amniocentesis cysts resolved
22 wk: termination Figure cysts
3. Bilateral in a fetus with
Table
2 of Reported
Summary
754
#{149} Radiology
of Trisomy
Cases
18 with
Choroid
Plexus
Cyst Source Nicolaides
Karyotype
et al (4)
Bundy et al (5) Ricketts et al (6) Farhood et al (7) Furness (8) Chitkara et al (9) Khouzam and Hooker(10) Fitzsimmons et al (11)
Gabrielli Clark (13) Hertzberg *
5j
judged
Postmortem I Mean size. t
(cm)
Age
(wk)
Location
18
Not
stated
24
Bilateral
Tnisomy
18
Not
stated
24
Trisomy
18
Not
stated
18
Tnisomy Tnisomy Trisomy Tnisomy Trisomy
18 21 18 18 18
Large* Not stated 0.5t Lange 2.0
18 23 20 15 18
Bilateral Bilateral Bilateral Not stated Bilateral Bilateral Bilateral
Tnisomy
18
1.2
17
Bilateral
0.5I 0.5t4 0.7t.t 1.2t4 0.8t4
I
Detailed anomaly scan (20-22 wk)
-
Figure
stated
Bilateral
US examination.
.-----.-------------..----
Nofurther
Cysts
Gestational
Tnisomy
18 18 18 Trisomy 18 Tnisomy 18 Fourcases of tnisomy 18 Tnisomy 21 Tnisomy 18
et al (14) from
Size
Trisomy Tnisomy Trisomy
et al (12)
DISCUSSION Fetal choroid plexus cysts are a common finding at autopsy in all age groups including the fetus (2). The sonographic detection of fetal choroid plexus cysts was first described by Chudleigh et al in 1984 in a report of five cases associated with uncomplicated pregnancies and healthy infants (3). Although it has become generally accepted that the vast majonity of fetal choroid plexus cysts are entirely benign, there are a growing number of reports indicating an association with tnisomy 18 and possibly tnisomy 21 . Nicolaides et al initially postulated the link when reporting three cases of tnisomy 18 out of four
of
pregnancy
large choroid plexus trisomy 18 (case 3).
(Fig 1). A typical example of bilateral cysts in a healthy fetus is shown in Figure 2. Follow-up scans at approximately 26 weeks gestation were obtained in 95 cases, and resolution of the cysts was seen in all but five. At about 30 weeks these persistent fetal chonoid plexus cysts had also resolved in four cases. We were unable to follow up the fifth patient. There were 98 live births: 95 healthy neonates, two neonates with trisomy 18, and one neonate with bilateral syndactyly of the second and third toes. Five otherwise healthy fetuses showed intrauterine growth netardation. One intrauterine death at 23 weeks gestation resulted from pneeclamptic toxemia. In the remaining fetus (Fig 3), the presence of large bilateral choroid plexus cysts and a diaphragmatic hernia prompted physicians to perform chromosomal analysis of the amniotic fluid. The results confirmed the diagnosis of trisomy 18, and the pregnancy was terminated at 21 weeks gestation. Table 1 summarizes the details of the three cases of tnisomy 18.
hernia
management
fetuses with choroid plexus cysts mefenred for fetal cord blood sampling (4). The authors’ conclusions have since been supported by the results of several anecdotal reports and a vaniety of studies. Excluding this present series, to our knowledge there have been 18 cases of trisomy
of fetal
18 and
choroid
two
cases
Termination of pregnancy
plexus
cysts.
of tnisomy
21 associ-
ated with fetal chonoid plexus cysts reported in the literature (4-14), and these are summarized in Table 2. Three cases of tnisomy 18 (diagnosed with the aid of chromosomal analysis) with fetal choroid plexus cysts were detected in this prospec-
June
1990
tive study. On reviewing the records of the cytogenetics department, which is responsible for all chromosomal analyses in the region, we found that only one additional case of tnisorny 18 (diagnosed postnatally) was recorded among the population without choroid plexus cysts. Therefore fetal chonoid plexus cysts are a fairly sensitive but nonspecific sign of tnisomy 18. This view is supported by Fitzsimmons et al, who found at postmortem US examination that 71% of fetuses with trisomy 18 that were aborted in the second trimester had choroid plexus cysts (1 1). The pathologic features of these cysts have occasionally been studied. Farhood et al described the histologic features of choroid plexus cysts in two healthy fetuses following elective abortion and in one fetus with trisomy 18 (7). In each fetus the cysts were surrounded by loose stromal tissue and did not have an epithelial lining. Postmortem studies in five cases of fetal chonoid plexus cysts (four with trisomy 18) reported by Gabrielli et al revealed cysts filled with clear fluid surrounded by normal chonoid plexus tissue (12). One disadvantage of screening a population for disease is that certain findings may be ambiguous and furthen, possibly invasive, tests would be required to determine whether disease is present. Amniocentesis and chorionic villus sampling are associated with a low, but significant, complication rate, and it is therefore desirable to define carefully the criteria for offering these tests to patients. With knowledge of the current available information, we suggest follow-
Vnlume
175
Number
#{149}
3
ing the scheme illustrated in Figure 4. It should be appreciated that since fetal choroid plexus cysts nearly always resolve, the size of the cysts will be influenced by the gestational age of the fetus at the time of scanning. All three cases of trisomy 18 in this report had bilateral cysts with a maximum diameter of 1 cm or more. This tendency for the cysts to be large and bilateral has been seen in previous reports (Table 2). Pensistence of the cysts beyond 26 weeks gestation occurs in both normal and trisomy 18 fetuses and is not a useful sign. The most important differentiating factor between normal and trisomy 18 fetuses is the detection of other structural abnormalities. Although it is not certain how sensitive these other anomalies are, it seems reasonable to offer a detailed scan if the cysts are 5 mm or larger with specific reference to the fingers, feet, heart, and abdominal wall. If the cysts are larger than 1 cm, the use of a confinmatory invasive test might be appropniate. In conclusion, although fetal choroid plexus cysts detected during the second trimester of pregnancy may be entirely benign in the majority of patients, a few will be associated with tnisomy 18. Features that positively correlate with the presence of trisomy 18 are large cysts, bilateral cysts, the presence of other structural abnormalities, and intrauterine growth retardation. The physician should take these factors into account before offering the patient an invasive prenatal diagnostic test. U
References 1.
2.
3.
Ostlere SJ, Irving HC, Lilford RJ. A prospective study of the incidence and significance of fetal choroid plexus cysts. Prenat Diagn 1989; 9:205-211. Shuangshoti 5, Netsky MG. Neuroepithelial (colloid) cysts of the nervous system. Neurology 1966; 16:887-903. Chudleigh
P, Pearce
JM,
Campbell
S.
The
prenatal diagnosis of transient cysts of the fetal choroid plexus. Prenat Diagn 1984; 4:135-137.
4.
Nicolaides KH, Rodeck CH, Gosden CM. Rapid karyotyping in nonlethal fetal malformations. Lancet 1986; 1:283-287.
5.
Bundy
6.
C, Emerson D, Doubilet PM. Antenatal sonographic findings in trisomy 18. J Ultrasound Med 1986; 5:361-364. Ricketts NEM, Lowe EM, Patel NB. Prenatal diagnosis of choroid plexus cysts. Lancet 1987; 1:213-214. Farhood Al, Morris JH, Bieber FR. Tran-
7.
AL,
sient
cysts
J Med Furness trisomy
9.
Chitkara
10.
11.
12.
of the
Genet
8.
kins
Saltzman
fetal
1987;
Prober
choroid
B, Fine
plexus.
Am
27:977-982.
ME. Choroid plexus cysts and 18 (letter). Lancet 1987; 2:693.
U, Cogswell
IA,
Mehalek
C, Norton
K, Wil-
K, Berkowitz
RL.
Cho-
roid plexus cysts in the fetus: a benign anatomic variant or pathological entity? report of 41 cases and review of the literature. Obstet Gynecol 1988; 72:185189. Khouzam MN, Hooker JC. The significance of prenatal diagnosis of choroid plexus cysts. Prenat Diagn 1989; 9:213216. Fitzsimmons J, Wilson D, Pascoe-Mason J, Shaw CM, Cyr DR. Mack LA. Choroid plexus cysts in fetuses with trisomy 18. Obstet Gynecol 1989; 73:257-260. Gabrielli
S, Reece
clinical
Clark cysts”
A, Pilu
significance
nosed choroid Gynecol 1989; 13.
DH,
SL. (letter).
Reply
G, et al.
The
of prenatally
plexus cysts. 160:1207-1210. to “Fetal Obstet
Gynecol
diag-
Am
J Obstet
choroid
plexus 1989;
73:302.
14.
Hertzberg BS, Kay HH, Bowie JD. Fetal choroid plexus lesions: relationship of antenatal sonographic appearance to clinical outcome. J Ultrasound Med 1989; 8:77-82.
Acknowledgment: We thank the ultrasound radiographers at St James’s University Hospital for their invaluable contribution to this study.
Radiology
#{149} 755
J.
Ostlere,
MRCP,
FRCR
C. Irving,
#{149} Henry
FRCR
#{149} Richard
Lilford,
J.
MRCOG,
MRCP,
PhD
fetal
chonoid
Fetal Choroid Plexus Cysts: A Report of 100 Cases’ A prospective study was undertaken to evaluate the prevalence and significance of fetal choroid plexus cysts detected on screening ultrasound (US) scans. One hundred cases of fetal choroid plexus cysts were detected from 11,700 examinations: There were 95 healthy newborns, three newborns with trisomy 18, one newborn with syndactyly of the toes, and one intrauterine death. In the three neonates with trisomy 18 the cysts were large (>1 cm in diameter), and additional abnormalities were detected. Although there is a clear association between fetal choroid plexus cysts and trisomy 18, amniocentesis or chorionic villus sampling should be reserved for high-risk patients with either large cysts or US evidence of other abnormalities. Index terms: Choroid plexus, neoplasms, 1617.31, 1617.1842 #{149} Choroid plexus, US studies, 1617.1298 #{149} Fetus, abnormalities, 856.874 Fetus, US studies, 856.1298 #{149} Trisomy 18 Radiology
1990;
#{149}
175:753-755
30
U)
20
z U.
0 10 0
z
0.1
0.2
0.3
0.4
0.5
lflnnr. !
0.6
SIZE
Figure
1.
0.7
0.8
0.9
CYST
OF
Distribution
1
1.1
1.2
1.3
1.4
1.5
(CUS)
of maximum
ameter in fetuses with choroid . = trisomy 18, D normal.
cyst
plexus
di-
cysts. Figure cysts
C
within the fetal choroid plexus are occasionally detected at ultrasound (US) scanning of women in the second trimester of pregnancy. Although the vast majority of these cysts resolve spontaneously and are not associated with any morbidity, several reports in the literatune have indicated a possible association between fetal choroid plexus cysts and chromosomal abnormalities, principally trisomy 18. To evaluate accurately the prevalence and significance of fetal chonoid plexus cysts, we undertook a prospective study involving approximately 1 1,700 routine dating scans. The first
MATERIALS
AND
METHODS
At our institution routine antenatal ing scanning is performed at approximately 16-18 weeks gestation. During first From the Departments of Radiology (S.J.O., H.C.I.) and Obstetrics (R.J.L.), St James’s University Hospital, Leeds LS9 7TF, England. From the 1989 RSNA annual meeting. Received November 6, 1989; revision requested December 20;
revision
received
January 16. Address c RSNA, 1990
January
reprint
1 1, 1990;
requests
Bilateral
plexus
fetus.
YSTS
7,000 scans, including 42 cases of fetal choroid plexus cysts, are the subject of a previous report (1).
1
2.
in a healthy
24 months
of the
scanning was art equipment
performed
on
(Hitachi
EUB
Medical,
Tokyo],
study,
60%
3.5-MHz
accepted
3.5-MHz
months formed
linear
array).
the
of all
state-of-the-
340
[Hitachi
curvilinear
nay) and 40% on an older model fenior spatial resolution (Hitachi
to H.C.I.
dat-
During
of the study all scanning on the Hitachi EUB 340.
an-
with inEUB 25, the
last
6
was perAll ex-
aminations included careful inspection of the choroid plexuses. All scans were necorded on photographic film and reviewed by a senior sonognaphen. When choroid plexus cysts were detected, follow-up scans were arranged at approximately 26 weeks. Further scans were obtamed if the cysts had not resolved or if other abnormalities were detected. All newborns underwent routine postnatal clinical examination. ysis was reserved
whom clinically
for
chromosomal
Chromosornal those neonates
abnormalities
analin
were
suspected.
RESULTS One hundred cases of fetal choroid plexus cysts were detected among the estimated 1 1,700 scans obtained oven a 21h-year period. Scans obtained with the newer Hitachi EUB 340 equipment showed fetal choroid plexus cysts in one of 90 pregnancies, compared with one of 300 when the older Hitachi EUB 25 was used. The cysts were bilateral in 52 fetuses, unilateral and multiple in six, and solitary in 42. When the long axis of the fetal head was perpendicular to the scan plane, 75% of the solitary cysts were detected in the plexus farthest from the scanning probe. The cysts varied considerably in size and shape 753
Table
1
Three
Cases
of Trisomy
18 with
Case
Cyst Size (cm)
Gestational Age (wk)
Location of Cysts
1
20
Bilateral
1
Choroid
Plexus
Follow-up 26 wk:
Cysts Additional Sonographic Findings
Findings
cysts
mal neonatal
resolved, head
nor-
Ventniculoseptal
scan
intrauterine
defect,
growth
re-
tardation
2
1.5
19.5
Bilateral
25 wk: cysts still present 31 wk: cysts resolved, normal neonatal head scan
Bilateral hydronephrosis, polyhydramnios, intrauterine growth retarda-
3
1.5
17
Bilateral
18 wk: 21 wk:
Diaphragmatic
tion amniocentesis cysts resolved
22 wk: termination Figure cysts
3. Bilateral in a fetus with
Table
2 of Reported
Summary
754
#{149} Radiology
of Trisomy
Cases
18 with
Choroid
Plexus
Cyst Source Nicolaides
Karyotype
et al (4)
Bundy et al (5) Ricketts et al (6) Farhood et al (7) Furness (8) Chitkara et al (9) Khouzam and Hooker(10) Fitzsimmons et al (11)
Gabrielli Clark (13) Hertzberg *
5j
judged
Postmortem I Mean size. t
(cm)
Age
(wk)
Location
18
Not
stated
24
Bilateral
Tnisomy
18
Not
stated
24
Trisomy
18
Not
stated
18
Tnisomy Tnisomy Trisomy Tnisomy Trisomy
18 21 18 18 18
Large* Not stated 0.5t Lange 2.0
18 23 20 15 18
Bilateral Bilateral Bilateral Not stated Bilateral Bilateral Bilateral
Tnisomy
18
1.2
17
Bilateral
0.5I 0.5t4 0.7t.t 1.2t4 0.8t4
I
Detailed anomaly scan (20-22 wk)
-
Figure
stated
Bilateral
US examination.
.-----.-------------..----
Nofurther
Cysts
Gestational
Tnisomy
18 18 18 Trisomy 18 Tnisomy 18 Fourcases of tnisomy 18 Tnisomy 21 Tnisomy 18
et al (14) from
Size
Trisomy Tnisomy Trisomy
et al (12)
DISCUSSION Fetal choroid plexus cysts are a common finding at autopsy in all age groups including the fetus (2). The sonographic detection of fetal choroid plexus cysts was first described by Chudleigh et al in 1984 in a report of five cases associated with uncomplicated pregnancies and healthy infants (3). Although it has become generally accepted that the vast majonity of fetal choroid plexus cysts are entirely benign, there are a growing number of reports indicating an association with tnisomy 18 and possibly tnisomy 21 . Nicolaides et al initially postulated the link when reporting three cases of tnisomy 18 out of four
of
pregnancy
large choroid plexus trisomy 18 (case 3).
(Fig 1). A typical example of bilateral cysts in a healthy fetus is shown in Figure 2. Follow-up scans at approximately 26 weeks gestation were obtained in 95 cases, and resolution of the cysts was seen in all but five. At about 30 weeks these persistent fetal chonoid plexus cysts had also resolved in four cases. We were unable to follow up the fifth patient. There were 98 live births: 95 healthy neonates, two neonates with trisomy 18, and one neonate with bilateral syndactyly of the second and third toes. Five otherwise healthy fetuses showed intrauterine growth netardation. One intrauterine death at 23 weeks gestation resulted from pneeclamptic toxemia. In the remaining fetus (Fig 3), the presence of large bilateral choroid plexus cysts and a diaphragmatic hernia prompted physicians to perform chromosomal analysis of the amniotic fluid. The results confirmed the diagnosis of trisomy 18, and the pregnancy was terminated at 21 weeks gestation. Table 1 summarizes the details of the three cases of tnisomy 18.
hernia
management
fetuses with choroid plexus cysts mefenred for fetal cord blood sampling (4). The authors’ conclusions have since been supported by the results of several anecdotal reports and a vaniety of studies. Excluding this present series, to our knowledge there have been 18 cases of trisomy
of fetal
18 and
choroid
two
cases
Termination of pregnancy
plexus
cysts.
of tnisomy
21 associ-
ated with fetal chonoid plexus cysts reported in the literature (4-14), and these are summarized in Table 2. Three cases of tnisomy 18 (diagnosed with the aid of chromosomal analysis) with fetal choroid plexus cysts were detected in this prospec-
June
1990
tive study. On reviewing the records of the cytogenetics department, which is responsible for all chromosomal analyses in the region, we found that only one additional case of tnisorny 18 (diagnosed postnatally) was recorded among the population without choroid plexus cysts. Therefore fetal chonoid plexus cysts are a fairly sensitive but nonspecific sign of tnisomy 18. This view is supported by Fitzsimmons et al, who found at postmortem US examination that 71% of fetuses with trisomy 18 that were aborted in the second trimester had choroid plexus cysts (1 1). The pathologic features of these cysts have occasionally been studied. Farhood et al described the histologic features of choroid plexus cysts in two healthy fetuses following elective abortion and in one fetus with trisomy 18 (7). In each fetus the cysts were surrounded by loose stromal tissue and did not have an epithelial lining. Postmortem studies in five cases of fetal chonoid plexus cysts (four with trisomy 18) reported by Gabrielli et al revealed cysts filled with clear fluid surrounded by normal chonoid plexus tissue (12). One disadvantage of screening a population for disease is that certain findings may be ambiguous and furthen, possibly invasive, tests would be required to determine whether disease is present. Amniocentesis and chorionic villus sampling are associated with a low, but significant, complication rate, and it is therefore desirable to define carefully the criteria for offering these tests to patients. With knowledge of the current available information, we suggest follow-
Vnlume
175
Number
#{149}
3
ing the scheme illustrated in Figure 4. It should be appreciated that since fetal choroid plexus cysts nearly always resolve, the size of the cysts will be influenced by the gestational age of the fetus at the time of scanning. All three cases of trisomy 18 in this report had bilateral cysts with a maximum diameter of 1 cm or more. This tendency for the cysts to be large and bilateral has been seen in previous reports (Table 2). Pensistence of the cysts beyond 26 weeks gestation occurs in both normal and trisomy 18 fetuses and is not a useful sign. The most important differentiating factor between normal and trisomy 18 fetuses is the detection of other structural abnormalities. Although it is not certain how sensitive these other anomalies are, it seems reasonable to offer a detailed scan if the cysts are 5 mm or larger with specific reference to the fingers, feet, heart, and abdominal wall. If the cysts are larger than 1 cm, the use of a confinmatory invasive test might be appropniate. In conclusion, although fetal choroid plexus cysts detected during the second trimester of pregnancy may be entirely benign in the majority of patients, a few will be associated with tnisomy 18. Features that positively correlate with the presence of trisomy 18 are large cysts, bilateral cysts, the presence of other structural abnormalities, and intrauterine growth retardation. The physician should take these factors into account before offering the patient an invasive prenatal diagnostic test. U
References 1.
2.
3.
Ostlere SJ, Irving HC, Lilford RJ. A prospective study of the incidence and significance of fetal choroid plexus cysts. Prenat Diagn 1989; 9:205-211. Shuangshoti 5, Netsky MG. Neuroepithelial (colloid) cysts of the nervous system. Neurology 1966; 16:887-903. Chudleigh
P, Pearce
JM,
Campbell
S.
The
prenatal diagnosis of transient cysts of the fetal choroid plexus. Prenat Diagn 1984; 4:135-137.
4.
Nicolaides KH, Rodeck CH, Gosden CM. Rapid karyotyping in nonlethal fetal malformations. Lancet 1986; 1:283-287.
5.
Bundy
6.
C, Emerson D, Doubilet PM. Antenatal sonographic findings in trisomy 18. J Ultrasound Med 1986; 5:361-364. Ricketts NEM, Lowe EM, Patel NB. Prenatal diagnosis of choroid plexus cysts. Lancet 1987; 1:213-214. Farhood Al, Morris JH, Bieber FR. Tran-
7.
AL,
sient
cysts
J Med Furness trisomy
9.
Chitkara
10.
11.
12.
of the
Genet
8.
kins
Saltzman
fetal
1987;
Prober
choroid
B, Fine
plexus.
Am
27:977-982.
ME. Choroid plexus cysts and 18 (letter). Lancet 1987; 2:693.
U, Cogswell
IA,
Mehalek
C, Norton
K, Wil-
K, Berkowitz
RL.
Cho-
roid plexus cysts in the fetus: a benign anatomic variant or pathological entity? report of 41 cases and review of the literature. Obstet Gynecol 1988; 72:185189. Khouzam MN, Hooker JC. The significance of prenatal diagnosis of choroid plexus cysts. Prenat Diagn 1989; 9:213216. Fitzsimmons J, Wilson D, Pascoe-Mason J, Shaw CM, Cyr DR. Mack LA. Choroid plexus cysts in fetuses with trisomy 18. Obstet Gynecol 1989; 73:257-260. Gabrielli
S, Reece
clinical
Clark cysts”
A, Pilu
significance
nosed choroid Gynecol 1989; 13.
DH,
SL. (letter).
Reply
G, et al.
The
of prenatally
plexus cysts. 160:1207-1210. to “Fetal Obstet
Gynecol
diag-
Am
J Obstet
choroid
plexus 1989;
73:302.
14.
Hertzberg BS, Kay HH, Bowie JD. Fetal choroid plexus lesions: relationship of antenatal sonographic appearance to clinical outcome. J Ultrasound Med 1989; 8:77-82.
Acknowledgment: We thank the ultrasound radiographers at St James’s University Hospital for their invaluable contribution to this study.
Radiology
#{149} 755
