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Ultrasound Obstet Gynecol 2004; 24 : 402–411Published online in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/uog.1718 Two- and three-dimensional sonographic assessment of thefetal face. 2. Analysis of cleft lip, alveolus and palate D. ROTTEN* and J. M. LEVAILLANT† Departments of Gynecology and Obstetrics, * Delafontaine Hospital, Saint-Denis and † Armand-Brillard Hospital, Nogent-sur-Marne,France KEYWORDS : 2D/3D sonography; alveolus; cleft lip; cleft lip with or without cleft palate; facial clefts; fetal face; labial clefts;palate; prenatal diagnosis ABSTRACT Objectives To describe the sonographic appearance of cleft lip with or without cleft palate (CL ± P) using two-dimensional and three-dimensional (3D) ultrasound imaging. Also, to evaluate the accuracy of ultrasound todelineate with precision the bony extent of facial clefts,i.e. to differentiate clefts limited to the lips, or extending to the alveolus/premaxilla or the secondary palate. Methods This was a retrospective study based on theexaminationoffetusesdiagnosedwithanisolatedCL ± P.Cases included were either discovered at systematicscreening or referred for further investigation. Clefts werecharacterized by their precise anatomical location and extent. The defect could include a cleft lip (CL), a cleft alveolus (CA), or a cleft of the secondary palate (CSP). Results We analyzed 96 cases of CL ± P. The mean gestational age at examination was 28 . 2 ± 4 . 1 weeks.The sonographic appearance of CL, CA, and CSP wasdepicted. Strict concordance of the sonographic report with the anatomical defect was present in 84 cases(87.5%). In eight cases, the severity of the cleft wasunderestimated: three cases of CA, four of CA + CSP and one of CSP were missed. In four cases, the cleft wasoverestimated as CA was incorrectly suspected. Conclusions Systematic screening with sonography todetect prenatally CL ± P requires the imaging of at least the mid-sagittal and the anterior coronal ‘nose-mouth’views. Once the presence of a facial cleft is suspected, thethree reference orthogonal planes are imaged in order tocharacterize the anatomical defect, and for each plane,the serial scans are thoroughly examined. This protocol allows precise delineation of the defect. Inclusion of 3Dand 4D ultrasound imaging in the examination protocol allows easier and more rapid screening and more preciseevaluation of the different cleft constituents. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd. INTRODUCTION The possibility of diagnosing craniofacial malformations in utero using sonography has long been recognized 1 .Among the various facial anomalies, clefts represent oneof the most frequent, with an incidence of approximately1 in 500–1000 live births 2–4 .The prenatal detection rate of this condition hastraditionally been very low, in particular at systematicscreening of low-risk pregnant women. However, in earlystudies, inclusion of the face in the examination protocolwas not always mandatory, nor was the examinationprotocolitselffullyadequatewhencomparedwithpresentstandards of fetal facial examination. More recent studiesreport values that range between 20% and 30% 2 , 5–10 .These numbers reflect better examination protocols andimprovements in sonographic equipment. For instance,the detection rate of facial clefts reported by Stoll et al . 6 increased from 5.3% during the study years 1979–1988,to 26.5% during the study years 1989–1998.Prenatal recognition of facial clefts will alert the physi-cian to perform chromosomal analysis and look for anassociated syndrome or non-syndromic polymalformativestate 11 , 12 . Precise characterization of the extent of cleft-ing permits counseling of the parents and planning of the birth in an appropriate tertiary center with adequateneonatal resources. Early diagnosis will allow the parentsto discuss with the surgeon the possibilities of correctivesurgery and, in more severe cases, termination of preg-nancy. In cases of complex clefting, the baby will requirerepeated surgical procedures, prolonged dental care and Correspondence to: Dr D. Rotten, Department of Gynecology and Obstetrics, Delafontaine Hospital, 2 rue du Docteur Pierre Delafontaine,F 93205 Saint-Denis, France (e-mail:
[email protected]) Accepted: 20 April 2004 Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd. ORIGINAL PAPER 2D/3D sonographic assessment of facial clefts 403 speech therapy, and may endure considerable medical,psychological and social problems 13–15 .The focus of this study was first to describe thesonographic appearance of lateral facial clefts, the so-called cleft lip with or without cleft palate (CL ± P),and second to evaluate the accuracy of ultrasoundto delineate their bony extent with precision. Morespecifically,our aim wastoassessthe value ofsonographyto differentiate clefts limited to the lips from thoseinvolving the alveolus/premaxilla, or those extending tothe secondary/posterior palate. The study was restrictedto the diagnosis of isolated clefts, thus excludingclefts associated with chromosomal anomalies or non-chromosomal recognized syndromes or polymalformativestates. Anterior midline clefts were also excluded asthey differ in presentation, associated anomalies (centralnervous system in particular), and in outcome fromCL ± P 2 , 3 , 16 , 17 . METHODSStudy population As previously reported 18 , the study population consistedmainly of a local population which was offeredroutine screening during pregnancy. Prenatal ultrasoundevaluation of the fetus was one of the three ultrasoundscreening examinations offered to all pregnant womenaccording to routine antenatal care in France. Forthe study of fetal morphology, examinations werepreferentially performed at 22 ± 1 gestational weeks, atthetimeofthesecondultrasoundscreen.Theexaminationincluded assessment of the head and face, thorax andheart, abdominal wall and viscera, spine and limbs. Thestudy population also comprised patients referred byother centers for confirmation of diagnosis in cases of suspicion of facial clefting or for presurgical evaluation.The diagnosis was usually suspected at the time of theultrasound screening examination,but, in some instances,later in pregnancy. For referred patients, the age atdiagnosis mentioned here refers to the gestational ageat diagnosis in our center.When anomalies were encountered each case wasinvestigated according to a standard protocol: detailedsonographic investigation, complementary imaging anddetermination of the karyotype, when necessary.The accuracy of the sonographic diagnosis wasascertained by correlation with postnatal findings, morespecifically those at surgery. Ultrasound examination The technique of the ultrasound examination of the facewasasdescribedpreviously 18 .Inshort,examinationswereperformed on a Combison 530 MT or a Combison 730(KretzTechnik, Zipf, Austria) ultrasound system, fittedwith a 5–8-MHz electronic linear transducer.Initially, two-dimensional (2D) ultrasound was per-formed. The mid-sagittal plane was obtained first. Afteranalysis of the sagittal planes, the transducer was rotated90 ◦ , and the axial planes were imaged. Then a secondrotation was effected, by sweeping the transducer in anarc over the woman’s abdomen. This allowed imaging of the coronal planes.Introduction of three-dimensional (3D) sonographyallowed a modification of the examination protocol.The mid-sagittal view was obtained and the 3D volumeacquired. The multiplanar reconstruction mode allowedthe simultaneous analysis of the three reference planes:sagittal, axial and coronal. Specific 3D modalities werealso used: surface rendering allowed imaging of the softtissues of the face and the transparency mode allowedpreferential imaging of the bony structures.The protocol was slightly modified when 4D sono-graphy became available. The mid-sagittal view wasobtained, and the surface-rendering mode initiated. Afterinspection of the fetal face, one of the recorded volumeswas chosen and analyzed using the multiplanar mode. Cleft terminology The anatomical structures that can be involved in antero-lateral clefts are the nose and lips, the alveolus/premaxillaand the secondary palate (Figure 1). In this study, cleftswere characterized by their precise anatomical locationand extent (Table 1 and Figure 2). We thus differenti-ated cleft lip (CL), clefts of the primary bony palate orcleft alveolus (CA), and clefts of the secondary palate(CSP). Labioalveolar clefts (CLAs) combine defects of thelip and alveolus (CL + CA). A complete orofacial cleftincludes the lip, the alveolus and the secondary palate(CLA + CSP). 12345678 Figure 1 Schematic diagram showing anatomy of the palate. 1,Incisor; 2, Intermaxillary suture; 3, Maxilla, premaxillary part; 4,Incisivo-canine suture; 5, Maxilla, palatine process; 6, Inter-palatalsuture; 7, Transverse palatal suture; 8, Palatal bone, horizontalplate.Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd. Ultrasound Obstet Gynecol 2004; 24 : 402–411. 404 Rotten and Levaillant Table 1 Classification of clefts Involved anatomical structureEmbryology-derived terminologyCommonterminology Analytical terminology Lip Cleft lip Cleft lip Cleft lip (CL), labioalveolar cleft (CLA)Premaxilla (alveolus and primary bony palate) Cleft lip Cleft palate Cleft alveolus (CA), labioalveolar cleftSecondary palate (palatine processes of themaxillary and palatine bones)Cleft palate Cleft palate Cleft of the secondary palate (CSP) Cleft lipCleft alveolusCleft of thesecondary palate Figure 2 Schematic representation of the various cleft constituentsof the palate. RESULTS During the study period, 106 cases of isolated CL ± Pwere diagnosed prenatally. All pregnancies ended in aliveborn child, except in one case of termination of pregnancy for an unrelated cause (maternal psychiatricillness). In 96 cases, the accuracy of the sonographicdiagnosis for the presence or absence of a cleft andits extent could be ascertained by comparison with thesurgical findings, or the pathological report in one case;in 10 cases, the surgical report was not available. Thesewere excluded from analysis. The classification of the96 cases according to their anatomical findings is shownin Table 2. There were no false-positive diagnoses of CL ± P. The mean ± SD gestational age at diagnosis was28 . 2 ± 4 . 1 (range, 22–39) weeks. Table 2 Study population Extent of clefting Unilateral Bilateral CL 15 0CLA 16 3CLA + CSP 42 * 20Total 73 23 * Including 1 left CLA + SP cleft associated with a right labial cleft.CL, cleft lip; CLA, cleft of the lip and alveolus; CSP, cleft of thesecondary palate. CL, uni- or bilateral, are analyzed in Table 3, anddepicted in Figure 3. Anomalies encountered when a cleftof the alveolus, uni- or bilateral, was present, are depictedin Table 4 and Figure 4. Anomalies encountered in thepresence of a CSP are depicted in Table 5 and Figure 5.As shown in Figure 6, the presence of a midline echoon the mid-sagittal view, immediately above the tongue,did not necessarily indicate palate integrity. When a CSPwas present, this echo was actually the low edge of thenasal septum and vomer.Table 6 correlates the sonographic with the anatomicaldiagnoses. Strict concordance was present in 84 cases(87.5%).In eight cases (8.3%), the sonographic examinationunderestimated the severity of the cleft. A CA wasmissed in three cases. In one unilateral CLA, the lipdefect was correctly diagnosed, but the alveolar defectwas not detected. In two bilateral CLA + CSP, thealveolar defect was missed on one side. In four unilateralCLA + CSP, both the alveolar defect and the secondarypalate extension were missed. Lastly, in one case of unilateral CLA + CSP, the alveolar defect was correctlydiagnosed,butthesecondarypalateextensionwasmissed.In six of the eight cases of underestimation withsonography, the surgical report mentioned the presenceof a submucous cleft, which involved the premaxilla (fivecases) or the secondary palate (one case). In two cases, thesurgery reportdescribedanincompletebonydefect,eitherof the premaxilla (one case) or of the secondary palate(one case). In the two remaining cases, no anatomicalparticularity was mentioned.Conversely, sonography overestimated the severity of the cleft in four cases (4.2%). A secondary palate defectwas suspected in three cases of unilateral CLA and in onebilateral CLA although the palate was intact at birth inall cases.No diagnosis of isolated CSP was made in the series.To our knowledge, two clefts were missed atsonography. A unilateral CL was missed at the 22-weekexamination. It was seen at the 32-week examination andwas included in the analysis. A unilateral CL, alveolusand palate in one twin was missed both at the 22- and32-week examination and was diagnosed at birth.As it was not possible to obtain postnatal informationfor all fetuses scanned in our center or referring centers,this study cannot address the false-negative rate of cleftdetection. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd. Ultrasound Obstet Gynecol 2004; 24 : 402–411. 2D/3D sonographic assessment of facial clefts 405 Figure 3 Ultrasound images of cleft lip. (a) Unilateral cleft lip(arrow), coronal oblique view. (b) Unilateral cleft lip, coronal view,three-dimensional (3D) surface analysis showing face and lip.(c) Unilateral cleft lip (arrow), axial view, showing maxilla (1,intact alveolar ridge; 2, lip). (d) Bilateral cleft lip, coronalnose-mouth view, 3D surface analysis (*, premaxillary prolabium;white arrows, lower limit of the clefts of the upper lip; black arrow,inferior lip). DISCUSSION The common terminology CL ± P has led to interpre-tative errors 3 , 14 . Cleft denomination is best based onembryology. The face and anterior palate derive fromthe fusion of the medial frontonasal process with thetwo lateral maxillary processes. These structures giverise to the upper lip and the premaxilla. The premax-illa corresponds to the part of the palate anterior tothe incisive foramen, thus consisting mainly of the gin-giva, the alveolar ridge and the bony palate anterior tothe canine teeth level. More caudally, the two maxil-lary palatal processes fuse, first with the correspondinganterior palate, and then, on the median line, with eachother, to form the secondary palate. The bony palateis thus composed of the palatal processes of the maxil-lary (anterior or primary part) and the palatal processesof the palatine bones (posterior or secondary part).Posteriorly, it is contiguous with the soft palate anduvula 19 .Anterolateralcleftsoriginatefromtheabsenceoffusionbetween the frontonasal process on one (unilateral clefts)or both (bilateral clefts) lateral maxillary process(es).They are located at the level of the incisivocanine suture.Whether they are limited to the lips and/or include thepremaxilla, they should be termed ‘cleft lips’. Anteriorclefts are represented by the arms of the ‘Y’, when thesymbolic ‘Y’ classification of clefts is used 20 .Posterior clefts srcinate from the absence of fusion of the two maxillary processes, together and with the vomerbone. They are paramedial, and either unilateral (in this Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd. Ultrasound Obstet Gynecol 2004; 24 : 402–411.
