Cleft Lip/Palate: Incidence of Prenatal Diagnosis in Glasgow, Scotland, and Comparison With Other Centers in the United Kingdom Paul Paterson, Haroon Sher, Faye Wylie, Shirley Wallace, R.G.N., Anne Crawford, R.G.N., Vikas Sood, B.Sc., F.D.S.R.C.S. (Eng.), M.R.C.S. (Eng.), Toby Gillgrass, M.Sc., F.D.S. (Orth.), Arup Ray, M.S., F.R.C.S. (Plast.), Mark Devlin, F.R.C.S.Ed. (O.M.F.S.), F.R.C.S., F.D.S.R.C.P.S. Objectives: To determine the proportion of children with cleft lip and/or cleft palate diagnosed prenatally between 1999 and 2008 in those referred for treatment to the Royal Hospital for Sick Children in Glasgow, Scotland (RHSC); and to compare the percentage prenatally diagnosed in 2008 versus other cleft treatment centers in the U.K. Method: A retrospective study was performed using medical records of the 459 cleft patients born and referred to RHSC between 1999 and 2008. Comparable data for year 2008 were requested from other U.K. units. Results: For the period studied, the percentage of all clefts diagnosed prenatally was 15%. This rose to 28% when only the cases of cleft lip with or without cleft palate (CL±P) were considered. An increase was seen in prenatal detection of CL±P from 11% in 1999 to 50% in 2008 (p = .011). Two of the six U.K. units that responded had a significantly higher percentage of CL±P cases diagnosed prenatally compared with RHSC in 2008 (p , .05). Conclusions: The percentage of CL±P cases diagnosed prenatally in this study is consistent with the literature and increased between 1999 and 2008. Routine ultrasound anomaly scanning is shown to significantly improve detection rates compared with scanning of high-risk pregnancies only. Cases of CL±P where the alveolus or the palate is involved have significantly higher detection rates than those involving only the lip. KEY WORDS:
anomaly scan, cleft, Glasgow, prenatal diagnosis, Scotland, UK, ultrasound
Orofacial clefts are the most commonly occurring congenital craniofacial anomalies, with a birth prevalence of approximately 1 in 700 in the U.K. (CLAPA, 2009).
Despite the fact that fetal ultrasonography was first used in the 1950s (Moller and Glaze, 2009), it was not until 1981 that the first facial cleft was diagnosed by this noninvasive technique. A case report by Christ and Meininger (1981) described how clinicians developed a routine of scanning the nose and lips to detect anomalies with real-time ultrasonography. Although the two reported cases were scanned at 28 and 33 weeks, the authors noted that the nose and lips could be visualized as early as 15 weeks and predicted the possibility of diagnosis before 28 weeks. A recommendation was made to attempt prenatal detection of this deformity to prepare parents for its appearance and treatment. The U.K. standard for ultrasonography used in the diagnosis of cleft lip with or without cleft palate (CL6P) is that of high-resolution two-dimensional (2D) ultrasound (Kennelly and Moran, 2008). Current recommendations for ultrasound screening in Scotland, as published by National Health Service Quality Improvement Scotland (NHS QIS, 2004), are as follows. During the first trimester, a transabdominal scan should be performed between 10 and 13 weeks’ gestation to confirm fetal viability, determine multiple pregnancy, detect major abnormalities, and assess the age of the fetus. This is often referred to as the
Paul Paterson, Haroon Sher, and Faye Wylie are fifth year dental students, University of Glasgow Dental Hospital & School, Glasgow, Scotland. Shirley Wallace and Anne Crawford are Clinical Nurse Specialists, West of Scotland Cleft Team, Royal Hospital for Sick Children, Glasgow, Scotland. Vikas Sood is Specialist Registrar in Oral and Maxillofacial Surgery, Regional Maxillofacial Unit, Southern General Hospital, Glasgow, Scotland. Toby Gillgrass is Consultant Cleft Orthodontist, Arup Ray is Consultant Cleft and Plastic Surgeon, and Mark Devlin is Consultant Cleft and Maxillofacial Surgeon, West of Scotland Cleft Team, Royal Hospital for Sick Children, Glasgow, Scotland. Presented at: National Managed Clinical Network for Cleft Services in Scotland Audit/Education Day, September 1, 2009, Perth Royal Infirmary, Scotland; and Scottish Oral and Maxillofacial Surgery Annual Conference, October 7, 2009, Aberdeen Royal Infirmary, Scotland. Submitted November 2009; Accepted August 2010. Address correspondence to: Paul Paterson, c/o Mr. Mark F. Devlin, Consultant Cleft and Maxillofacial Surgeon, Regional Maxillofacial Unit, Southern General Hospital, 1345 Govan Road, Glasgow G51 4TF, Scotland, United Kingdom. E-mail
[email protected]. DOI: 10.1597/09-238 608
Paterson et al., INCIDENCE OF PRENATAL CLEFT DIAGNOSIS IN GLASGOW
‘‘booking scan.’’ A transabdominal anomaly scan should be offered to all women in the second trimester from 18 to 22 weeks. This is used to screen the fetus for congenital abnormalities, including CL6P. Indeed, CL6P is best identified between weeks 20 and 22 (Johnson and Sandy, 2003). The NHS QIS report noted the variation in prenatal scans offered to women in Scotland. During the study period, most maternity units offered only anomaly scans to mothers designated at high risk of congenital anomalies. Individual procedures may vary between hospitals, but the ‘‘high–risk’’ category includes such maternal characteristics as diabetes mellitus; bleeding during pregnancy; the use of in vitro fertilization; risk factors for Down syndrome; and family history of orofacial clefts, spina bifida, or congenital cardiac defects. Although conventional 2D ultrasound is capable of detecting CL6P with reported sensitivity of up to 90% (Wayne et al., 2002), identification of isolated cleft palate (CP) proves more elusive. It has been suggested that this is so because the alveolar ridge obscures the view of the palatal defect in an axial plane (Kennelly and Moran, 2008). Another explanation is that the tongue may obliterate the cleft in some instances (Cash et al., 2001). Methods to better visualize the developing palate include 3D reverse face ultrasound, wherein a computer-reconstructed 3D model of the face can be rotated to inspect the palate (Campbell et al., 2005), and Doppler imaging. The latter can identify a cleft palate by recording the motion of amniotic fluid through the defect (Kennelly and Moran, 2008). The question may be asked, Why is the prenatal diagnosis of clefts important? From a purely technical viewpoint, a prenatal diagnosis of orofacial clefting can lead to discovery of other congenital abnormalities (Nyberg et al., 1995), the diagnosis of which is important to the management of the patient. However, perhaps more interesting is the effect a prenatal diagnosis has on parents. Prenatal detection of facial clefts has been shown to be useful in preparing parents for the birth of a baby with this deformity and in reassuring them regarding its subsequent management (Christ and Meininger, 1981). Indeed, informing parents beforehand regarding the care and feeding of the baby can reduce perinatal anxiety and morbidity (Johnson and Sandy, 2003). Aside from these two major benefits, mention has been made of the ability to meet the cleft team before birth and to prepare other family members for the possible appearance of the child (Moller and Glaze, 2009). Possible disadvantages of knowing about the condition during pregnancy include heightened stress of the parents and complications resulting from this (Moller and Glaze, 2009). Additionally, the risk of termination of pregnancy is increased. A review of several studies, however, concluded that only a small proportion (ranging from 0% to 27%) of prenatal diagnoses of nonsyndromic clefts resulted in termination of the pregnancy (Johnson and Sandy, 2003).
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TABLE 1 Data Collected for Patients Born Between 1999 and 2008 and Referred to RHSC*{ Data Item
Possible Values
Date of birth Sex Hospital from which referred Cleft type
Cleft side (Note: Not applicable in case of CP [always midline].) Prenatal diagnosis Presence of other abnormalities (syndromic cases)
Years 1999–2008 M/F — Cleft palate only (CP) Submucous cleft palate (SMCP)* Cleft lip only (CL) Cleft lip and alveolus (CLA) Cleft lip and palate (CLP) Right (R)/Left (L)/Bilateral (B) Midline (M) Yes/No Yes/No
* Submucous cleft palate was defined as a defect of bone or muscle underlying intact mucosa and affecting the hard or soft palate. { RHSC 5 Royal Hospital for Sick Children.
Despite the disadvantages, most parents of children with clefts diagnosed prenatally are in favor, with one study reporting 89% favorable results (Davalbhakta and Hall, 2000). The main objectives of this study were to report on the percentage of cleft lip and/or cleft palate cases diagnosed prenatally from 1999 to 2008 in those referred to the Royal Hospital for Sick Children in Glasgow, Scotland (RHSC), for treatment, and to compare the data for 2008 versus those from other U.K. units. The data collected also allowed the performance of individual maternity hospitals to be compared, and permitted investigation of the effect of cleft side, extent, and associated abnormalities on prenatal diagnosis rates. Throughout this text, references made to the year of study relate to children born in that year. METHOD This study was of an observational retrospective design based on the medical records of children with clefts born from 1999 to 2008 and referred to RHSC for treatment. Data were collected for 459 babies with cleft lip and/or cleft palate over this period and were categorized by year of birth. Data were obtained from the managed clinical network for cleft services in Scotland (CLEFSiS). Ethical approval was granted by Greater Glasgow and Clyde Health Board. Table 1 shows the data collected for each patient. The data for each year were aggregated, and values were presented for the 10-year period as a whole. The percentage of cases diagnosed prenatally was compared with published values. From these results, it was clear that CP is rarely diagnosed prenatally; further investigation of prenatal diagnosis frequency therefore concentrated on CL6P. Trends were investigated in the following variables over time: (1) percentage of all cleft cases diagnosed prenatally; (2) percentage of CL6P cases diagnosed prenatally (to
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exclude the effects of the low detection rate of CP); and (3) percentage of total cleft cases made up by CL6P (to investigate whether CL6P was becoming more or less common and therefore affecting total prenatal diagnosis rate). To establish whether a statistically significant change in any of these variables occurred over time, a chi-square test of independence was performed for each. Data were grouped into 2-year blocks to ensure that expected frequencies were high enough for reliable application of the tests. The null hypothesis for each test was that no association existed between year of birth and the variable under investigation. Confidence levels of 95% were used throughout. For any variables in which a trend was identified, linear regression was used to fit a straight line to a graph of the data, in the hope of quantifying the strength of the trend. A breakdown of the data was performed for four maternity hospitals that referred patients to RHSC, because differences in prenatal diagnosis frequency were noted among them. The hospitals were selected on the basis that they referred a total of more than 10 CL6P patients to RHSC over the study period, and they had sonographers available for interview. For the 10-year study period, individual hospitals had their percentages of prenatally diagnosed CL6P cases calculated. Chi-square tests of independence were used to compare these values between hospitals. To help explain these data, interviews were held with sonographers from each of the four hospitals. The main focus of the interviews was to establish whether routine anomaly scans were offered to mothers during the study period, and at which point during pregnancy anomaly scans were performed. Where routine scanning was not offered, the criteria for performing an anomaly scan were recorded. Using all 10 years’ worth of data, chi-square tests were performed to evaluate whether side of cleft, extent of cleft, or presence of associated abnormalities had any significant influence on prenatal diagnosis of CL6P. The ‘‘extent of cleft’’ was defined to compare prenatal diagnosis in two groups of children: those with CL on its own, and those with cleft lip and alveolus (CLA) or cleft lip and palate (CLP). Comparable data pertaining to prenatal diagnosis of CL6P and CP were requested from other units in the U.K. Six of a possible 10 respondents replied. The data from each unit were compared with those obtained for 2008 from RHSC. The following variables were investigated: (1) percentage of cases that were CL6P, as opposed to CP only; (2) percentage of all clefts diagnosed prenatally; and (3) percentage of CL6P cases diagnosed prenatally. Comparisons were performed using six chi-square tests per variable; in this way, the data from RHSC were compared with those from each of the other U.K. units that replied.
FIGURE 1 Percentage of CL±P cases diagnosed prenatally against year of birth.
RESULTS For the 459 cleft cases referred to RHSC over the 10-year study period, the overall percentage diagnosed prenatally was 15% (70 cases). The value for CL6P was markedly greater at 28% (65 of 236 cases). CP on its own was diagnosed prenatally on only 5 of 223 occasions (2%); four of the five were associated with other abnormalities that may have accounted for the diagnosis. Of all cases, 51% were CL6P. The first variable under investigation over time was the percentage of all cleft cases diagnosed prenatally. Although this value rose from 13% to 28% between 1999 and 2008, no statistically significant association with year of birth was noted (p 5 .366). The percentage of CL6P cases diagnosed prenatally, however, did demonstrate a significant trend (p 5 .011). Figure 1 shows a graph of these data. It can be seen that the percentage of CL6P cases diagnosed prenatally rose from 11% to 50% between 1999 and 2008. A trend line was fitted to the graph via linear regression. The F-test for linearity returned a p value of .024, which means that a straight line is a good approximation of the trend. The slope of the fitted line is 2.99, indicating that the percentage of CL6P cases diagnosed prenatally rose approximately 3% every year. (The 95% confidence interval for this value is 0.52 to 5.47.) The percentage of all cleft cases made up by CL6P was also investigated against year of birth. No statistically significant trend was found (p 5 .226). Table 2 shows details of the four selected maternity hospitals that referred patients to RHSC. It can be seen that the hospital that provided routine 18- to 22-week anomaly scanning to all mothers had a significantly higher 10-year cumulative percentage of CL6P cases diagnosed prenatally. The effects of cleft side, extent, and associated abnormalities were investigated in relation to the percentage of CL6P cases diagnosed prenatally. Table 3 summarizes these results. For cleft side, it is evident that, although the
Paterson et al., INCIDENCE OF PRENATAL CLEFT DIAGNOSIS IN GLASGOW
TABLE 2 Ten-Year Cumulative Percentage of CL±P Cases Diagnosed Prenatally for Selected Hospitals Referring to RHSC*
Hospital Number
Ultrasound Scanning Policy
1
Routine anomaly scanning Scan high-risk only Scan high-risk only Scan high-risk only
2 3 4
% Prenatal Diagnosis of CL6P
p Value for Comparison With Hospital Number 1{
83
Not applicable
45 33 15
.032 .003 .0001
* CL6P 5 cleft lip with or without cleft palate; RHSC 5 Royal Hospital for Sick Children. { p values for chi-square tests included.
percentage prenatally diagnosed in each category of cleft is different (bilateral being the highest), the results are not statistically significant (p 5 .111). However, the extent of the cleft did have a significant effect on its prenatal diagnosis: The more extensive the cleft, the higher the percentage of cases that were diagnosed prenatally (p 5 .048). This means that a significantly higher percentage of cases from the group of children with CLA or CLP (as opposed to cleft lip [CL] on its own) were diagnosed prenatally. No significant link between associated abnormalities and a prenatal diagnosis of CL6P was found (p 5 .637). Table 4 and Figure 2 contain 2008 data received from six other U.K. units, as well as from RHSC. The results of chisquare tests performed to compare the U.K. units versus RHSC values are summarized in Table 5. It can be seen that Cleft Net East had a significantly higher percentage of CL6P cases diagnosed prenatally than RHSC (p 5 .003), as did South Wales (South West Managed Clinical Network, p 5 .00002). The latter also had a significantly higher percentage of all clefts diagnosed prenatally (p 5 .002). It is interesting to note that no unit had a significantly different ratio of CL6P cases to CP only when compared with RHSC. DISCUSSION The results of a literature review of studies related to prenatal diagnosis of cleft lip and/or cleft palate are displayed in Table 6. The percentage of all clefts diagnosed prenatally from 1999 to 2008 at RHSC was 15%. For the subset of cases that were CL6P, the cumulative percentage prenatal diagnosis was much higher, at 28%. This is to be expected because the cases of CP (which are rarely diagnosed) were excluded. A review of the results for CP, with only five cases diagnosed prenatally for the entire study period, justifies the view that CP was rarely prenatally diagnosed in this study. Further evidence for this can be seen in the majority of papers referenced in Table 6, in which only two studies reported any prenatal detection of CP. Four of the five cases of CP diagnosed prenatally were accompanied by other anomalies. One explanation offered
611
TABLE 3 Effects of Cleft Side, Cleft Extent, and Associated Abnormalities on Prenatal Diagnosis of CL±P*{
Number of Cases
Number Prenatally Diagnosed
% Prenatal Diagnosis
Cleft side (p 5 .111) Right Left Bilateral
70 117 48
14 33 18
20 28 38
Cleft extent (p 5 .048) CL only CLA/CLP
55 181
8 57
15 31
Associated abnormalities (p 5 .637) Yes No
22 214
7 58
32 27
* CL 5 cleft lip; CLA 5 cleft lip and alveolus; CLP 5 cleft lip and palate; CL6P 5 cleft lip with or without cleft palate. { p values for chi-square tests included.
is that in hospitals where no routine anomaly scanning was performed, maternal risk factors for other anomalies would have justified a detailed ultrasound scan, leading to an increased chance of diagnosing CP prenatally. It should be noted, however, that CP is difficult to diagnose using conventional 2D ultrasound (Kennelly and Moran, 2008). Therefore, it may be suggested that the presence of more severe structural abnormalities alerted the sonographer to the possible presence of CP, increasing the likelihood that CP would be prenatally diagnosed. Pierre Robin sequence, in which cleft palate is a common feature, is a good example of such a condition. The percentages of cases diagnosed prenatally in Table 6 are variable. This may be explained by the different locations and time periods of the studies, as well as by variations in ultrasound procedures, equipment, and training. Results from RHSC compare favorably with those of Clementi et al. (2000)—the study with the largest sample size based on 20 databases throughout Europe, including the U.K. The first variable examined for a trend was the percentage of all cleft cases diagnosed prenatally. The fact that no statistically significant change had occurred throughout the study period (p 5 .366), despite the value increase from 13% (1999) to 28% (2008), can be explained by the inclusion of CP cases in these values, with their low detection rate. It could have been argued that a change in the proportion of cases that were CL6P as opposed to CP had affected the overall prenatal diagnosis trend. For example, if CP cases were on the increase, then overall detection rate may have been reduced. However, no trend in the ratio of CP compared to CL6P cases was found (p 5 .226). As for the percentage of CL6P cases diagnosed prenatally, the statistically significant increase of around 3% per year (from 11% in 1999 to 50% in 2008) was the main finding of this study (p 5 .011). Variations in procedures, equipment, and staffing at each referring
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TABLE 4
U.K. Unit Data for 2008, for Comparison With RHSC*
Unit
Royal Hospital for Sick Children, Glasgow Cleft Net East Northern and Yorkshire Cleft Service North Thames Cleft Service Spires Cleft Service South Thames Cleft Service South Wales/South West Managed Clinical Network
Cleft Cases
CL6P Cases
% CL6P Cases
Total Prenatal Diagnoses
% Prenatal Diagnoses
CL6P Prenatal Diagnoses
% Prenatal Diagnoses (CL6P)
CP Prenatal Diagnoses
61 85 65 117 93 127
34 44 30 60 49 74
56 52 46 51 53 58
17 36 18 42 21 43
28 42 28 36 23 34
17 36 18 42 21 42
50 82 60 70 43 57
0 0 0 0 0 1
73
43
59
40
55
40
93
0
* CL6P 5 cleft lip with or without cleft palate; CP 5 cleft palate; RHSC 5 Royal Hospital for Sick Children.
maternity hospital made it impossible to give a definitive reason for this increase. Another important result was obtained by examining the cumulative 10-year percentage of CL6P cases diagnosed prenatally at the four selected maternity hospitals (Table 2). The data strongly suggest that routine anomaly scanning produces higher detection rates of CL6P compared with scanning of only high-risk pregnancies. The effects of cleft side, cleft extent, and associated abnormalities on prenatal diagnosis were examined, with only the extent of cleft proving significant in this study (p 5 .048)—15% of CL was detected compared with 31% of CLA/CLP. The presence of CLA or CLP compared with CL only is, indeed, known to increase prenatal diagnosis rates; one study (Cash et al., 2001) detected 67% of CL cases and 93% of cases of CLP. A possible explanation for this is that involvement of the alveolus or palate in the cleft produces a larger defect that is more easily detected by ultrasonography than CL on its own. As for cleft side, this study produced no statistically significant conclusion (p 5 .111), although bilateral clefts were detected in 38% of cases compared with unilateral clefts in only 25%. Similar papers have reported more frequent prenatal diagnosis of bilateral cases (Hanikeri et al., 2006). No significant effect of associated abnormalities on prenatal diagnosis of CL6P
was found (p 5 .637), despite the fact that this relationship was widely accepted in the literature (Clementi et al., 2000). For 2008, comparison with other U.K. units revealed that the hospitals in this study, in general, were offering similar prenatal diagnosis rates to the rest of the U.K. Only 2 U.K. units had a significantly higher prenatal diagnosis rate for CL6P. Unfortunately, not enough information was available to consider why this was so. The proportion of cases at RHSC made up by CL6P was not significantly different compared with other U.K. units; therefore, this was not a factor in any differences in detection rates. CONCLUSION The percentage of CL6P cases referred to RHSC that had a prenatal diagnosis rose significantly between 1999 and 2008. Figures for the 10 years as a whole compare favorably with those of several previous publications. This study therefore builds upon existing literature, adding validity with its relatively large number of cases (459) and 10-year duration. The conclusion that routine anomaly scanning leads to significantly higher rates of prenatal detection of CL6P provides statistical evidence to supplement existing publications. In addition, this finding is useful in supporting the recommendations of NHS QIS regarding the widespread implementation of routine anomaly scanning (NHS QIS, 2004). Indeed, from the end of 2009, many more Scottish TABLE 5 Results of Chi-Square Tests to Compare RHSC With Other U.K. Units*
Unit
Cleft Net East Northern and Yorkshire Cleft Service North Thames Cleft Service Spires Cleft Service South Thames Cleft Service South Wales/South West Managed Clinical Network
FIGURE 2 Comparison of other U.K. units versus RHSC data for the year 2008.
% Prenatal Diagnoses (CL6P) (p Value)
% CL6P Cases (p Value)
% Prenatal Diagnoses (p Value)
.635
.073
.003
.282 .572 .710 .743
.982 .280 .457 .409
.423 .054 .521 .512
.712
.002
.00002
* CL6P 5 cleft lip with or without cleft palate; RHSC 5 Royal Hospital for Sick Children.
Paterson et al., INCIDENCE OF PRENATAL CLEFT DIAGNOSIS IN GLASGOW
TABLE 6
613
Selected Studies Reporting on Prenatal Diagnosis of Orofacial Clefts*
Study
Location and Period of Study
Chitty et al. (1991) Boyd et al. (1998) Clementi et al. (2000) Shaikh et al. (2001) Cash et al. (2001) Wayne et al. (2002) Hanikeri et al. (2006) Russell et al. (2008) Offerdal et al. (2008)
England 1988–89 England 1991–96 Europe 1996–98 England 1991–98 England 1993–97 England 1996–2000 Western Australia 1996–2003 Canada 1992–2002 Norway 1987–2004
All Cleft Cases{
9 25 751 270 26 12 216 225 101
(2) (12) (161) (23) (17) (9) (48) (29) (35)
% of Total Diagnosed Prenatally
22.2 48.0 21.4 8.5 65.3 75 22.2 12.9 34.7
CL6P Cases{
7 25 553 130 17 10 114 127 77
(2) (12) (148) (23) (15) (9) (47) (29) (35)
% of CL6P Cases Diagnosed Prenatally
28.6 48.0 26.8 17.7 88.2 90.0 41.2 22.8 45.5
CP Cases{
2 0 198 140 9 1 95 98 24
(0) (0) (13) (0) (2) (0) (0) (0) (0)
% of CP Cases Diagnosed Prenatally
0 N/A 6.6 0 22.2 0 0 0 0
* CL6P 5 cleft lip with or without cleft palate; CP 5 cleft palate; N/A 5 not applicable. { Number of cases is followed by number prenatally diagnosed in parentheses.
hospitals will offer this routine scanning as more funding becomes available. The data pertaining to Scottish hospitals also provide statistical weight behind the previously reported increase in prenatal detection of CL6P when the alveolus or the palate is involved (in addition to the lip). Comparison with other U.K. units revealed that the performance of Scottish hospitals for year 2008 was similar, with only two U.K. units having significantly higher prenatal detection rates of CL6P. Acknowledgments. The cleft team at the Royal Hospital for Sick Children, Glasgow. The sonographers at Queen Mother’s Hospital; Dumfries and Galloway Royal Infirmary; Wishaw General Hospital; and Southern General Hospital. The following U.K. units that provided data for comparison: South West Cleft Unit (Frenchay Hospital); North Thames Cleft Service; East of England Cleft Lip and Palate Network; The Spires Centre; Northern and Yorkshire Cleft Lip and Palate Service; and South Thames Cleft Service.
REFERENCES Boyd PA, Chamberlain P, Hicks NR. 6-year experience of prenatal diagnosis in an unselected population in Oxford, UK. The Lancet. 1998;352:1577–1581. Campbell S, Lees C, Moscoso G, Hall P. Ultrasound antenatal diagnosis of cleft palate by a new technique: the 3D reverse face view. Ultrasound Obstet Gynecol. 2005;25:12–18. Cash C, Set P, Coleman N. The accuracy of antenatal ultrasound in the detection of facial clefts in a low-risk screening population. Ultrasound Obstet Gynecol. 2001;18:432–436. Chitty LS, Hunt GH, Moore J, Lobb M. Effectiveness of routine ultrasonography in detecting fetal structural abnormalities in a low risk population. BMJ. 1991;303:1165–1169. Christ JE, Meininger MG. Ultrasound diagnosis of cleft lip and cleft palate before birth. Plast Reconstr Surg. 1981;68:854–859.
CLAPA. Understanding cleft lip & palate: about cleft lip and palate. Available at http://www.clapa.com/medical/cleft_lip_article/107/. Accessed August 13, 2009. Clementi M, Tenconi R, Bianchi F, Stoll C. Evaluation of prenatal diagnosis of cleft lip with or without cleft palate and cleft palate by ultrasound: experience from 20 European registries. Prenat Diagn. 2000;20:870–875. Davalbhakta A, Hall PN. The impact of antenatal diagnosis on the effectiveness and timing of counselling for cleft lip and palate. Br J Plast Surg. 2000;53:298–301. Hanikeri M, Savundra J, Gillett D, Walters M, McBain W. Antenatal transabdominal ultrasound detection of cleft lip and palate in Western Australia from 1996 to 2003. Cleft Palate Craniofac J. 2006;43:61–66. Johnson N, Sandy JR. Prenatal diagnosis of cleft lip and palate. Cleft Palate Craniofac J. 2003;40:186–189. Kennelly MM, Moran P. Directional power Doppler in the midsagittal plane as an aid to the prenatal diagnosis of cleft lip and palate. Prenat Diagn. 2008;28:56–58. Moller KT, Glaze LE. Cleft Lip and Palate: Interdisciplinary Issues and Treatment. 2nd ed. Austin, TX: Pro-Ed; 2009. National Health Service Quality Improvement Scotland. Health Technology Assessment Advice 5: Routine ultrasound scanning before 24 weeks of pregnancy, 2004. Available at http://www.nhshealthquality.org/ nhsqis/1209.html. Accessed August 14, 2009. Nyberg DA, Sickler GK, Hegge FN, Kramer DJ, Kropp RJ. Fetal cleft lip with and without cleft palate: US classification and correlation with outcome. Radiology. 1995;195:677–684. Offerdal K, Jebens N, Syvertsen T, Blaas HGK, Johansen OJ, Eik-Nes SH. Prenatal ultrasound detection of facial clefts: a prospective study of 49 314 deliveries in a non-selected population in Norway. Ultrasound Obstet Gynecol. 2008;31:639–646. Russell KA, Allen VM, MacDonald ME, Smith K, Dodds L. A population-based evaluation of antenatal diagnosis of orofacial clefts. Cleft Palate Craniofac J. 2008;45:148–153. Shaikh D, Mercer NS, Sohan K, Kyle P, Soothill P. Prenatal diagnosis of cleft lip and palate. Br J Plast Surg. 2001;54:288–289. Wayne C, Cook K, Sairam S, Hollis B, Thilaganathan B. Sensitivity and accuracy of routine antenatal ultrasound screening for isolated facial clefts. Br J Radiol. 2002;75:584–589.