1. HOMEHELPFEEDBACKSUBSCRIPTIONSARCHIVESEARCHTABLE OF CONTENTSTop of FormQUICK SEARCH: [advanced]Author:Keyword(s):Year: Vol: Page: Bottom of Form This ArticleFigures Only Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map ServicesEmail this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing ArticlesCiting Articles via HighWire Citing Articles via Google Scholar Google ScholarArticles by Levine, D.Articles by Edelman, R.Search for Related Content PubMedPubMed Citation Articles by Levine, D. Articles by Edelman, R. Social Bookmarking What's this? Hotlight (NEW!)What's Hotlight? AJR 2000; 175:1067-1069© American Roentgen Ray Society Case Report Tuberous Sclerosis in the Fetus Second-Trimester Diagnosis of Subependymal Tubers with Ultrafast MR Imaging D. Levine1,2, P. Barnes1, B. Korf3 and R. Edelman1 1 Department of Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Ave., Boston, MA 02215.2 Department of Obstetrics and Gynecology, Beth Israel Deaconess Medical Center, Boston, MA 02215.3 Center for Human Genetics, HIM, Ste. 640, 77 Ave. Louis Pasteur, Boston, MA 02115. Received January 19, 2000; accepted after revision February 28, 2000. Supported by grant NS 37945 from the National Institutes of Health. Address correspondence to D. Levine. Introduction TopIntroductionCase ReportDiscussionReferences Tuberous sclerosis is an autosomal dominant multisystem disorder with effects on the skin, brain, heart, and other organs. The estimated prevalence is approximately one case per 6000—10,000 individuals. The classic findings are angiofibroma, epilepsy, and mental retardation. Mental retardation of a moderate to severe degree occurs in approximately half of the patients. Seizures are present in 60-80% of patients. Two genes, designated TSC1 (9q34) and TSC2 on (16p13), are associated with tuberous sclerosis complex [1, 2]. Genetic testing is not yet available for prenatal diagnosis because of the genetic heterogeneity of the tuberous sclerosis complex and the wide variety of mutations, many of which are not amenable to the commonly used mutation detection systems. Antenatal diagnosis has previously been based on the sonographic detection of cardiac rhabdomyomas [3]. These rhabdomyomas can be seen in the mid second trimester, as early as 20 weeks [4]. The diagnosis of tuberous sclerosis complex increases with the number of tumors, with from 30% or less of the cases occurring when a single rhabdomyoma is present to 80% when two or more tumors are present [5]. In a study by Sonigo et al. [6], 87% of fetuses with cardiac rhabdomyomas had tuberous sclerosis. However, only approximately half of the patients with tuberous sclerosis have cardiac rhabdomyomas [7], most of which are not present at the typical time of prenatal screening at 20 weeks' gestation. This finding emphasizes the issue that currently available screening for tuberous sclerosis complex lacks sensitivity in the second trimester. In this report, we describe the visualization of a subependymal tuber at 21 weeks' gestation on prenatal MR imaging. Use of prenatal MR imaging in addition to prenatal sonography has the potential to improve genetic counseling and prenatal diagnosis of patients with tuberous sclerosis. Case Report TopIntroductionCase ReportDiscussionReferences A 31-year-old woman presented for genetic counseling because her husband and one child have tuberous sclerosis. As part of a research protocol, approved by the committee on clinical investigations at Beth Israel Deaconess Medical Center, she was enrolled to have fetal sonography and fetal MR examinations at 21 and 32 weeks' gestational age. Written informed consent was obtained. At the time of the first sonogram, the fetus was noted to have two cardiac rhabdomyomas (Fig. 1A). The remainder of the sonographic fetal survey, including images of the brain, was normal. The patient was counseled that the fetus likely was affected with tuberous sclerosis and that the results of the MR examination likely would not change her treatment. She elected to continue in the research protocol. View larger version (148K):[in this window][in a new window][as a PowerPoint slide] Fig. 1A. —31-year-old woman who presented for genetic counseling because her husband and one child have tuberous sclerosis. Fetus was screened for tuberous sclerosis. Oblique sonogram obtained at 21 weeks' gestational age shows echogenic mass (arrow) in left ventricle of heart consistent with rhabdomyoma. MR imaging was performed of the fetus on a 1.5-T superconductive system (Vision; Siemens, Erlangen, Germany) with a four-element phased array surface coil. The whole-body specific absorption rate was less than 3.0 W/kg. Half-Fourier acquisition single-shot turbo spin-echo (HASTE) images were acquired in the axial, coronal, and sagittal planes (echo spacing, 4.2 msec; effective TE, 60 msec; echo train length, 72; number of acquisitions, one; section thickness, 4 mm; field of view, 26 x 35 cm; acquisition matrix, 192 x 256). A 130° refocusing pulse was used to minimize the amount of radiofrequency power deposition. The scan time was 420 msec per image with a 1-sec delay between acquisitions applied to decrease the specific absorption rate. An image from each scan served as the scout for the subsequent sequence. The total scan time for a single data acquisition of 13 sections was 17 sec. The MR examination revealed a focal 2-mm low-signal-intensity nodule in the periventricular region on the right (Fig. 1B). This nodule was seen in two separate image acquisitions in orthogonal planes. The lesion caused a contour deformity of the ventricular wall. The patient was counseled that this lesion likely was a subependymal tuber, but because prenatal diagnosis had not been made previously at this early gestational age, it was not certain whether this finding could be an artifact. View larger version (119K):[in this window][in a new window][as a PowerPoint slide] Fig. 1B. —31-year-old woman who presented for genetic counseling because her husband and one child have tuberous sclerosis. Fetus was screened for tuberous sclerosis. Coronal half-Fourier acquisition single-shot turbo spin-echo (HASTE) MR image obtained at 21 weeks' gestational age shows 2-mm low-signal-intensity nodule (arrow) in subependymal region. The patient elected to continue the pregnancy and returned for imaging at 32 weeks' gestation. At that time, three cardiac rhabdomyomas were visualized on sonography. The remainder of the sonographic fetal survey, including images of the brain, was normal. Fetal MR imaging showed at least seven subependymal low-signal-intensity nodules, one of which was in the region seen on the MR images at 21 weeks' gestational age (Figs. 1C and 1D), and one subcortical low-signal-intensity nodule. View larger version (135K):[in this window][in a new window][as a PowerPoint slide] Fig. 1C. —31-year-old woman who presented for genetic counseling because her husband and one child have tuberous sclerosis. Fetus was screened for tuberous sclerosis. Coronal (C) and sagittal (D) HASTE MR images at 32 weeks' gestational age show low-signal-intensity nodule (arrow) in location similar to that seen in B. Other low-signal-intensity nodules were seen in subependymal and subcortical regions (not shown). View larger version (163K):[in this window][in a new window][as a PowerPoint slide] Fig. 1D. —31-year-old woman who presented for genetic counseling because her husband and one child have tuberous sclerosis. Fetus was screened for tuberous sclerosis. Coronal (C) and sagittal (D) HASTE MR images at 32 weeks' gestational age show low-signal-intensity nodule (arrow) in location similar to that seen in B. Other low-signal-intensity nodules were seen in subependymal and subcortical regions (not shown). MR imaging after birth was performed using a standard neonatal brain protocol. The image in this case report has the following scan parameters: a TR/TE of 500/14, two acquisitions, 4-mm section thickness, a field of view of 17.5 x 20 cm, and an acquisition matrix of 112 x 256. This study confirmed the presence of multiple subependymal and cortical tubers (Fig. 1E). View larger version (134K):[in this window][in a new window][as a PowerPoint slide] Fig. 1E. —31-year-old women who presented for genetic counseling because her husband and one child have tuberous sclerosis. Fetus was screened for tuberous sclerosis. Sagittal T1-weighted MR image obtained on day of birth shows high-signal-intensity nodule (arrow) in location similar to that in D. Other subependymal and cortical tubers also were present (not shown). A second case of second-trimester diagnosis of (presumed) tuberous sclerosis is shown in Figure 2. Review of 180 fetal MR examinations revealed no similar subependymal lesions in patients examined for other indications. View larger version (153K):[in this window][in a new window][as a PowerPoint slide] Fig. 2. —37-year-old woman was referred at 24 weeks' gestation for tuberous sclerosis screening because three cardiac rhabdomyomas were seen on routine prenatal sonogram. No family history of tuberous sclerosis was present. Axial half-Fourier acquisition single-shot turbo spin-echo MR image shows multiple small low-signal-intensity nodules (arrows) in periventricular regions that were seen on orthogonal image planes (not shown) and caused contour abnormality of ventricular margin. Patient was counseled that these findings likely were subependymal tubers but that specificity of these findings was unknown. Patient elected to terminate pregnancy. No autopsy was performed. Discussion TopIntroductionCase ReportDiscussionReferences The underlying brain lesions of tuberous sclerosis are subependymal nodules and cortical tubers. Subependymal nodules are situated at the edges of the lateral ventricles. The subependymal nodules of tuberous sclerosis have been detected in a preterm fetus as early as at 28 weeks' gestational age [8]. The prenatal visualization of tubers has been reported by Sonigo et al. [6] in the third trimester in fetuses with sonographically detected cardiac rhabdomyomas. In their study, the researchers sedated the pregnant women to decrease fetal motion, and they used T1-weighted imaging. In our patients, we did not use sedation, and we used T2-weighted imaging. The tubers appear dark on this sequence either because of magnetic susceptibility artifacts (from calcification) and/or low concentration of mobile water. The tubers stand out on the T2-weighted images because they are adjacent to the bright signal of water in the cerebrospinal fluid spaces. To avoid confusing these lesions with artifacts, we set our criteria for subependymal lesions to be seen on at least two scanning sequences in orthogonal planes and to cause a contour deformity of the ventricular wall. Multiplicity of lesions increases the likelihood that tuberous sclerosis is the cause of the lesions. Although in the two patients reported here, the prenatal diagnosis of tuberous sclerosis was suggested on the basis of the cardiac findings of rhabdomyomas, the finding of cortical tubers at such an early gestational age has not previously been possible. Use of the ultrafast MR technique of HASTE allowed prenatal visualization of cortical tubers without maternal or fetal sedation. Because cortical tubers are more common than cardiac rhabdomyomas and because cardiac rhabdomyomas are not frequently visualized on sonography until the third trimester, it is possible that MR imaging combined with sonography would allow improved prenatal diagnosis of tuberous sclerosis complex. Further studies will be needed to determine the sensitivity and specificity of prenatal MR imaging for screening for tuberous sclerosis complex. References TopIntroductionCase ReportDiscussionReferences van Slegtenhorst M, de Hoogt R, Hermans C, et al. Identification of the tuberous sclerosis gene TSC1 on chromosome 9q34. Science 1997;277:805 -808[Abstract/Free Full Text] The European Chromosome 16 Tuberous Sclerosis Consortium. Identification and characterization of the tuberous sclerosis gene on chromosome 16. Cell 1993;75:1305 -1315[Medline] Crawford DC, Garett C, Tynan M, Neville BG, Allan LD. Cardiac rhabdomyomata as a marker for the antenatal detection of tuberous sclerosis. J Med Genet 1983;20:303 -312[Abstract/Free Full Text] Wallace G, Smith FIC, Watson GH, Rimmer S, D'Souza SW. Tuberous sclerosis presenting with fetal and neonatal cardiac tumors. Arch Dis Child 1990;65:377 -379[Abstract/Free Full Text] Christophe C, Bartholome J, Blum D, et al. Neonatal tuberous sclerosis: US, CT and MRI diagnosis of brain and cardiac lesions. Pediatr Radiol 1989;6:446 -448 Sonigo P, Elmaleh A, Fennont L, Delezoide AL, Mirlesse V, Brunelle F. Prenatal MRI diagnosis of fetal cerebral tuberous sclerosis. Pediatr Radiol 1996;26:1 -4[Medline] Bass JL, Breningstall GN, Swaiman KF. Echocardiographic incidence of cardiac rhabomyoma in tuberous sclerosis. Am J Cardiol 1985;55:1379 -1382[Medline] Sharp D, Robertson DM. Tuberous sclerosis in one infant of 28 weeks' gestational age. Can J Neurol Sci 1983;10:59 -62[Medline] CiteULike Complore Connotea Del.icio.us Digg Reddit Technorati What's this? This article has been cited by other articles: P. D Griffiths, M. N J Paley, E. Widjaja, C. Taylor, and E. H WhitbyIn utero magnetic resonance imaging for brain and spinal abnormalities in fetusesBMJ, September 10, 2005; 331(7516): 562 - 565. [Full Text] [PDF] D. Levine, P. D. Barnes, R. R. Robertson, G. Wong, and T. S. MehtaFast MR Imaging of Fetal Central Nervous System AbnormalitiesRadiology, October 1, 2003; 229(1): 51 - 61. [Abstract] [Full Text] [PDF] This ArticleFigures Only Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map ServicesEmail this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing ArticlesCiting Articles via HighWire Citing Articles via Google Scholar Google ScholarArticles by Levine, D.Articles by Edelman, R.Search for Related Content PubMedPubMed Citation Articles by Levine, D. Articles by Edelman, R. Social Bookmarking What's this? Hotlight (NEW!)What's Hotlight? HOMEHELPFEEDBACKSUBSCRIPTIONSARCHIVESEARCHTABLE OF CONTENTS