Löbel Ulrike, Catala Martin, D'Arco Felice, Lequin Maarten H, Pasquariello Rosa, Ilves Pilvi, Loorits Dagmar, Tähepõld Annika, Pezzetti Giulio, Craven Ian, Severino Mariasavina, Rossi Andrea
From the Department of Radiology (U.L., F.D.), Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
Laboratory of Developmental Biology (M.C.), CNRS, Sorbonne-University, IPBS, Paris, France.
AJNR Am J Neuroradiol. 2025 Apr 2;46(4):808-814. doi: 10.3174/ajnr.A8534.
Duplication of the pituitary gland is a rare developmental anomaly. Multiple associated craniofacial malformations have previously been reported with the largest series to date consisting of 5 patients. In this multi-institutional series of 10 patients, we present a detailed review of the imaging features and discuss a possible overarching pathogenesis that would explain most of the detected malformations.
Inclusion criteria for this retrospective imaging review were the presence of a pituitary stalk and gland duplication and the characteristic appearance of the hypothalamic ventral midline. In addition to the clinical presentation, we recorded the imaging findings of 10 patients (9 girls) through onsite and online reviews. Genetic analysis was available for 6 patients.
The duplicated pituitary stalk and gland showed normal imaging appearances in all patients. Mammillary bodies were clearly identified lateral to the characteristic prominence of the hypothalamic ventral midline. Strands of tissue extending to the anterior dura ("limited ventral myeloschisis") were noted at the medulla oblongata in 10, and at the cervical spinal cord in 7 patients. The medulla oblongata showed a "butterfly" appearance on axial images in 9 patients. Ten patients had cervical segmentation anomalies ("zipperlike"), 9 had anterior-posterior brainstem patterning defects (small pons, elongated medulla), and corpus callosum measurements were abnormal in all patients. Three patients each presented with diencephalic-mesencephalic junction abnormalities and 4 with an anterior mesencephalic "cap." An oropharyngeal teratoma was present in 4 patients. Genetics was normal in 3 of the 6 patients studied; the remainder were found to have mutations in and a gene variant of , 2 copies of 7 and 8 exon of gene, and 2.126 megabase duplication at bands q11.1 and q11.2 of 1 chromosome 15, respectively.
Duplication of the pituitary gland presents as well-defined craniofacial and cervical spine malformation phenotype. Axial mesoderm duplication generating an excess of Sonic Hedgehog may be the primary embryologic driver leading to this condition.
垂体重复是一种罕见的发育异常。此前已有多例伴有多种相关颅面畸形的报道，迄今为止最大的系列报道包含5例患者。在这个由10例患者组成的多机构系列研究中，我们详细回顾了影像学特征，并讨论了一种可能的总体发病机制，该机制可以解释大多数检测到的畸形。
本次回顾性影像学研究的纳入标准为存在垂体柄和腺体重复以及下丘脑腹侧中线的特征性表现。除了临床表现外，我们通过现场和在线评估记录了10例患者（9名女性）的影像学检查结果。6例患者进行了基因分析。
所有患者的垂体柄和腺体重复均表现出正常的影像学外观。乳头体在丘脑腹侧中线的特征性隆起外侧清晰可见。10例患者在延髓处、7例患者在颈髓处可见延伸至硬脑膜前部的条索状组织（“有限的腹侧脊髓裂”）。9例患者的延髓在轴位图像上呈“蝴蝶”状。10例患者存在颈椎节段异常（“拉链样”），9例患者存在脑干前后模式缺陷（脑桥小、延髓拉长），所有患者的胼胝体测量均异常。3例患者出现间脑-中脑交界处异常，4例患者出现中脑前部“帽状”结构。4例患者存在口咽畸胎瘤。6例接受研究的患者中，3例基因正常；其余患者分别在 基因中发现突变和一个基因变体、基因7和8外显子的2个拷贝以及1号染色体15q11.1和q11.2带处的2.126兆碱基重复。
垂体重复表现为明确的颅面和颈椎畸形表型。轴向中胚层重复产生过量的 Sonic Hedgehog 可能是导致这种情况的主要胚胎学驱动因素。
