The computed tomography and MRI imaging findings in a case of pituitary duplication and epipharyngeal teratoma are described in a newborn baby girl with respiratory difficulties. Associated skull base and central nervous system malformations are presented. Teratoma diagnosis was confirmed by histology. The embryological pathogenesis is discusse

Boltshauser, Eugen

Fischer, Ursin

Gysin, Claudine

Huisman, Thierry

Straube, Torsten

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IntroductionPituitary gland duplication is an extremely rare mal-formation. Reviewing the current literature, we foundthat approximately 23 cases have been reported [1–15].The largest series includes ﬁve children from the Hos-pital for Sick Children, Toronto [13]. Pituitary glandduplication has been reported to occur in complexmidline and skull base anomalies including partialtwinning and median cleft face syndrome. Associatednasopharyngeal teratomas have been observed [5, 8, 12,13, 15]. The exact knowledge of the spectrum of asso-ciated malformations increases diagnostic accuracy andcould possibly result in a better understanding of theembryogenesis of the malformation. We present theimaging ﬁndings of a newborn baby girl with a naso-pharyngeal teratoma and a complex of associatedmidline malformations including pituitary gland dupli-cation.Case reportA baby girl, born after an uneventful pregnancy of38 weeks, presented with respiratory distress on day 1 oflife. Physical examination raised the suspicion of anasopharyngeal obstruction. Endoscopic examinationshowed a soft tissue mass protruding from the naso-pharynx into the mesopharynx through a partially cleftpalate. The lesion presented as a hairy mass with areasthat resembled hemangiomatous components as well asectodermal components including epidermis. She hadThierry A. G. M. HuismanUrsin FischerEugen BoltshauserTorsten StraubeClaudine GysinPituitary duplication and nasopharyngealteratoma in a newborn: CT, MRI, USand correlative histopathological findingsReceived: 15 November 2004Accepted: 10 January 2005Published online: 8 June 2005 Springer-Verlag 2005Abstract The computed tomogra-phy and MRI imaging ﬁndings in acase of pituitary duplication andepipharyngeal teratoma are de-scribed in a newborn baby girl withrespiratory diﬃculties. Associatedskull base and central nervous sys-tem malformations are presented.Teratoma diagnosis was conﬁrmedby histology. The embryologicalpathogenesis is discussed.Keywords Pituitary duplication ÆTeratoma Æ MalformationNeuroradiology (2005) 47: 558–561DOI 10.1007/s00234-005-1374-8 PAEDIATRIC NEURORADIOLOGYT. A. G. M. Huisman (&) Æ T. StraubeDepartment of Diagnostic Imaging,University Children’s Hospital Zurich,Steinwiesstrasse 75, 8032 Zurich,SwitzerlandE-mail: thierry.huisman@kispi.unizh.chTel.: +41-1-266-7110Fax: +41-1-266-7158U. Fischer Æ C. GysinDivision of Ear, Nose and Throat Surgery,University Children’s Hospital Zurich,Steinwiesstrasse 75, Zurich, SwitzerlandE. BoltshauserDepartment of Neurology,University Children’s Hospital Zurich,Steinwiesstrasse 75, Zurich, Switzerlandmildly dysmorphic facial features with hypertelorism.No other associated abnormalities were seen. Bloodoxygenation levels were always within normal limits.Because of poor feeding, a gastric tube was inserted forfeeding. Neurological examination was unremarkable.The child’s biometrics were within normal limits. Familyhistory was unremarkable.MRI was performed on day 5 of life. A T1- and T2-heterogeneous soft tissue mass with inclusion of fattycomponents and calciﬁcations was seen within the roofof the epipharynx in tight connection to the sphenoidbone (Fig. 1). The maximal diameter was 2.8 cm. Themass protruded through a partially cleft palate into thedorsal part of the mesopharynx. The choanes werepartially obliterated by the mass. MRI also showed acomplete duplication of the pituitary gland including thepituitary stalk. The mammillary bodies and the tubercinereum were fused into a single midline mass resultingin a thickening of the third ventricle ﬂoor. The olfactorybulb was lacking on one side. In addition, a partialduplication of the distal basilar artery was seen. Hy-pertelorism was conﬁrmed; eye globes and optic nerveswere without pathology. The central nervous system wasotherwise normal; speciﬁcally, no additional midlinemalformations were seen.Computer tomography (CT) was added on day 9 oflife for a precise preoperative evaluation of the osseousskull base. CT showed a bony cleft within the sphenoid(Fig. 2). A wide separation of the anterior clinoid pro-cesses was seen as well as a wide dorsal aspect of thebony nasal septum. The sella was separated into twodistinct cavities containing both pituitary glands sepa-rated by a bony ridge. The epipharyngeal mass showed amixture of hypodense fatty components (negativeHounsﬁeld units) next to hyperdense bony and hypo-dense soft tissue contents indicative of a mature tera-toma. The partially cleft palate was conﬁrmed.Otherwise the skull base was unremarkable.Ultrasonography of the abdomen did not show anyadditional malformations or midline defects. The bonyskeleton including the entire spine was also without signsof fusion or segmentation anomalies.The child was operated on 7 days later. The soft tis-sue mass could be resected without complications. Tu-mor histology conﬁrmed the diagnosis of a matureteratoma (Fig. 3). No cerebrospinal ﬂuid leakage oc-curred. The surgical reconstruction of the cleft palate isplanned at 18 months of age. The child is thriving anddeveloping well since operation.Fig. 1 a Coronal T1-weightedprecontrast and postcontrastspin echo (SE) (upper row) andT2-weighted fast SE (FSE)(lower row) magnetic resonance(MR) images. A full duplicationof the pituitary gland includingthe pituitary stalk and the in-fundiblum as well as a fusion ofthe mammillary bodies and thetuber cineurum with thickeningof the ﬂoor of the third ventricleis seen. b Coronal T1-weightedSE (left) and T2-weighted FSE(center and right) MRI. T1-hyperintense fat is seen withinthe nasophayrngeal teratoma(left). The coronal T2-weightedFSE image (center) reveals anormal left olfactory bulb,while the right olfactory bulb islacking. In addition, a partialduplication of the distal basi-lary artery is observed (right).c Sagittal T2-weighted FSE MRimage. A thickening of the ﬂoorof the third ventricle due tofusion of the mammillarybodies and the tuber cinereumis seen next to the heteroge-neous partially T2 hyperintenseand hypointense teratomawithin the epipharynx adajcentto the sphenoid bone559DiscussionPituitary duplication is a rare congenital malformation[1–15]. Several articles have described associated mal-Fig. 1 (Contd.)Fig. 2 Coronal and axial computer tomography (bone windowsetting). Hyperdense calciﬁcations within the nasophayngealteratoma as well as a sagittal cleft within the widened sphenoidbone is visualizedFig. 3 Histological slices (hematoxylin–eosin staining) of thenasopharyngeal teratoma. a Cartilage and bone with an inter-spersed stroma are seen. b Stratiﬁed squamous epithelium, hairfollicles, and sebaceous glands surrounded by adipose tissue areseen560formations involving the skull base, midline centralnervous system structures and the epipharynx. Inaccordance with the previous reports, in our case allpreviously reported associated malformations wereidentiﬁed. Until recently the pituitary gland was be-lieved to have a double embryonic origin [4, 8, 9, 11,12]. The anterior lobe of the pituitary gland was be-lieved to arise from the oral ectoderm, and the pos-terior lobe from the neuroectoderm. According to thisembryological theory, a diverticulum (Rathke pouch)originating from the roof of the stomodeum fuses withthe downward extending neurohypophyseal bud/dien-cephalic diverticulum. An early report dating back to1957 in which Morton [9] studied a case of pituitaryduplication questioned this theory. A pituitary dupli-cation cannot be explained in this way. Morton as-sumed that a duplication of the prochordal plate andthe anterior end of the notochordal process at the15th–16th day of pregnancy would lead to a duplica-tion of the stomatodaeal region as a whole, and to twoareas of persisting contact between neural and surfaceectoderms, resulting in two pituitary glands. Mesodermis then believed to surround and separate the twostomatodaeal areas. In this way, normal structureswould form laterally and duplications would occurmedially.Kollias et al. [8] reviewed the literature and supportthe theory of Morton by stating that notochordalduplication and subsequent prochordal plate duplica-tion is a prerequisite for pituitary gland duplication. Thesame pathogenetic mechanism is also suggested for othercentral nervous system malformations, including dias-tematomyelia. Why a duplication of the prochordalplate and the anterior end of the notochordal processoccurs remains unknown. Numerous factors, includingmaternal exposure to teratogenic factors, have beendiscussed [8].Similar to our case, several reports described associ-ated epipharyngeal teratoma in cases of pituitaryduplication [4, 8, 9, 11, 12]. It has consequently beenhypothesized that midline inclusion dermoids early inpregnancy could result in a splitting of the pituitarygland primordium [12]. Whether the inclusion of mes-enchymal structures, as a precursor of a teratoma, actsas a primary trigger that induces splitting of the noto-chord or whether the development of a teratoma resultsfrom the splitting of the notochord remains unclear. Theoccurrence of associated skull base and midline mal-formations in pituitary gland duplication could alsoindicate a multifactorial etiology.In our case, ultrasonography excluded associatedmajor abdominal malformations.Further research focussed on the development of thehypophyseal–hypothalamic axis and the skull base isindicated. Reports of this extremely rare malformation,especially of the imaging ﬁndings, could possibly givemore insight in the understanding of this complex mal-formation.References1. Bagherian V, Graham M, Gerson LP,Amstrong DL (1984) Double pituitaryglands with partial duplication of facialand brain structures with hydrocepha-lus. Comput Radiol 8:203–2102. Bainborogh AR, Hase S (1958) Doublehypophysis. Can Med Assoc J 79:912–9133. Bale PM, Reye RD (1976) Epignathus,double pituitary and agenesis of corpuscallosum. J Pathol 120:161–1644. Burke M, Zinkovsky S, Abrantes M,Riley W (2000) Duplication of thehypophysis. Pediatr Neurosurg 33:95–995. Hamon-Kerautret M, Ares GS, Dem-ondion X, Rouland V, Francke J-P,Pruvo J-P (1998) Duplication of thepituitary gland in a newborn withmedian cleft face syndrome and nasalteratoma. Pediatr Radiol 28:290–2926. Hori A (1983) A brain with twohypophyses in median cleft face syn-drome. Acta Neuropathol 59:150–1547. Il’Ina EG, Laziuk GI (1989) A new caseof the ‘‘double hypophysis-multiplecongenital developmental defects’’complex. Tsitol Genet 23:45–468. Kollias SS, Ball WS, Prenger EC (1995)Review of the embryologic developmentof the pituitary gland and report of acase hypophyseal duplication detectedby MRI. Neuroradiology 37:3–129. Morton WRM (1957) Duplication ofthe pituitary and stomatodaeal struc-tures in a 38-week male infant. Arch DisChild 32:135–14110. Roesmann U (1985) Duplication of thepituitary gland and spinal cord. ArchPathol Lab Med 109:518–52011. Ryals BD, Brown DC, Levin SW (1993)Duplication of the pituitary gland asshown by MR. AJNR Am J Neurora-diol 14:137–13912. Shah S, Pereira JK, Becker CJ, RoubalSE (1997) Duplication of pituitarygland. J Comput Assist Tomogr 21:459–46113. Shroﬀ M, Blase S, Jay V, Chitayat D,Armstrong D (2003) Basilar arteryduplication associated with pituitaryduplication: a new ﬁnding. AJNR Am JNeuroradiol 24:956–96114. Tagliavini F, Pilleri G (1986) Mam-millo-hypophyseal duplication (diplo-mammillo-hypophysis). Acta Neuropa-thol 69:38–4415. Uchino A, Sawada A, Takase Y, FujitaI, Kudo S (2002) Extreme fenestrationof the basilar artery associated with cleftpalate, nasopharyngeal mature tera-toma, and hypophyseal duplication.Eur Radiol 12:2087–2090561

Pituitary duplication and nasopharyngeal teratoma in a newborn: CT, MRI, US and correlative histopathological findings

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Pituitary duplication and nasopharyngeal teratoma in a newborn: CT, MRI, US and correlative histopathological findings

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