Congenital anomalies in the teratological collection of Museum Vrolik in Amsterdam, The Netherlands. IV: closure defects of the neural tube

From Monsters to Malformations: Anatomical Preparations as Objects of Evidence for a Developmental Paradigm of Embryology, 1770-1850

A common object found within medical museums is the developmental series: an arrangement of embryos depicting the transformation of an unremarkable blob into an anatomically organized and recognizable organism. The developmental series depicts a normative process, one where bodies emerge in reliable sequential stages to reveal anatomically perfect beings. Yet a century before the developmental series would become a visual model of embryological development, the very process of development itself was discerned through the comparative study of preserved human fetuses-specifically, those deemed "monstrous" or characterized as "malformations." This article examines how anatomically diverse fetal bodies were reformulated from singular curiosities into alternative developmental pathways whose characteristics testified to the laws of nature and to the primordial, physical relationship between humans and other species. In early nineteenth century Amsterdam, the father-son team of physicians Gerard and Willem Vrolik built up an internationally renowned anatomical museum famous especially for Willem's collection of fetal malformations. Physical preparations of fetal malformations play a central role in Willem's monumental handbook on developmental embryology: comparing human embryos against one another and the embryos of other species, Willem plots out a sequence of embryological development in which a body's form marks its place within the ever-unfolding natural order. In conversation with the literature on model organisms, this article explores how the "monstrous" gets standardized and, in doing so, contributes to the scientific production of a normative physiological process.

History and highlights of the teratological collection in the Museum Anatomicum of Leiden University, The Netherlands

The anatomical collection of the Anatomical Museum of Leiden University Medical Center (historically referred to as Museum Anatomicum Academiae Lugduno-Batavae) houses and maintains more than 13,000 unique anatomical, pathological and zoological specimens, and include the oldest teratological specimens of The Netherlands. Throughout four centuries hundreds of teratological specimens were acquired by more than a dozen collectors. Due to the rich history of this vast collection, teratological specimens can be investigated in a unique retrospective sight going back almost four centuries. The entire 19th century collection was described in full detail by Eduard Sandifort (1742-1814) and his son Gerard Sandifort (1779-1848). Efforts were made to re-describe, re-diagnose and re-categorize all present human teratological specimens, and to match them with historical descriptions. In the extant collection a total of 642 human teratological specimens were identified, including exceptional conditions such as faciocranioschisis and conjoined twins discordant for cyclopia, and sirenomelia. Both father and son Sandifort differed in their opinion regarding the causative explanation of congenital anomalies. Whereas, their contemporaries Wouter Van Doeveren (1730-1783) and Andreas Bonn (1738-1817) both presented an interesting view on how congenital anomalies were perceived and explained during the 18th and 19th centuries; the golden age of descriptive teratology. Although this enormous collection is almost 400 years old, it still impresses scientists, (bio)medical students, and laymen visiting and exploring the collections of the Museum Anatomicum in Leiden, The Netherlands.

A detailed musculoskeletal study of a fetus with anencephaly and spina bifida (craniorachischisis), and comparison with other cases of human congenital malformations

Few descriptions of the musculoskeletal system of humans with anencephaly or spina bifida exist in the literature. Even less is published about individuals in which both phenomena occur together, i.e. about craniorachischisis. Here we provide a detailed report on the musculoskeletal structures of a fetus with craniorachischisis, as well as comparisons with the few descriptions for anencephaly and with musculoskeletal anomalies found in other congenital malformations. We focused in particular on the comparison with trisomies 13, 18, and 21 because neural tube defects have been associated with such chromosomal defects. Our results showed that many of the defects found in the fetus with craniorachischisis are similar not only to anomalies previously described in the available works on musculoskeletal phenotypes seen in fetuses with anencephaly and spina bifida, but also to a wide range of other different conditions/syndromes including trisomies 13, 18 and 21, and cyclopia. The fact that similar anomalies are seen commonly not only in a wide range of different syndromes, but also as variants of the normal human population and as the 'normal' phenotype of other animals, supports Pere Alberch's unfortunately named idea of a 'logic of monsters'. That is, it supports the idea that development is so constrained that both in 'normal' and abnormal development one sees certain outcomes being produced again and again because ontogenetic constraints only allow a few possible outcomes, thus also leading to cases where the anatomical defects of some organisms are similar to the 'normal' phenotype of other organisms. In fact, this applies not only to specific anomalies but also to general patterns, such as the fact that in pathological conditions affecting different regions of the body, one consistently sees more defects on the upper limbs than on the lower limbs. Such general patterns are, again, seen in the fetus examined for this study, which had 29 muscle anomalies on the right upper limb and 22 muscle anomalies on the left upper limb, vs. seven muscle anomalies on the right lower limb and two on the left lower limb. It is therefore hoped that this work, which is part of our effort to describe and compile information on human musculoskeletal defects found in a wide range of conditions, will contribute not only to a better understanding of craniorachischisis in particular and of human congenital malformations in general, but also to broader discussions on the fields of comparative anatomy, and developmental and evolutionary biology.

Malformations of the axial skeleton in the museum Vrolik: II: craniosynostoses and suture-related conditions

The Museum Vrolik collection of anatomical specimens in Amsterdam, The Netherlands, comprises over 5,000 specimens of human and animal anatomy, embryology, pathology, and congenital anomalies. Recently, we rediagnosed a subset of the collection comprising dried infantile, juvenile, and adult human skulls with congenital and acquired conditions. On external examination and additional radiography, we found 58 skulls with craniosynostosis (CS) involving one or more sutures and 40 skulls with a presumed suture related condition. Most of these were part of the material collected and described by Louis Bolk (1866-1930). Analysis of his observations suggests that skull deformation because of premature suture closure depends not only on the identity of the sutures involved but also on the timing and progression of their closure and the extent of their involvement. Moreover, premature closure of the sagittal suture after 3-6 years of age appeared to be much more common than expected because it is not accompanied by skull deformation. Many of the skulls with single-suture CS were microcephalic, which may be the cause of the premature synostosis. By contrast, microcephaly may be a resulting phenomenon in multi-suture CS. We noticed that the quotient between height of the cranial vault (vertex-porion distance) and head circumference, multiplied by 100, was 26 or higher only in those CS cases with multi-suture involvement. We therefore consider this parameter, which we named "acrocephalic index", to be an indicator of multi-suture involvement in individual CS cases. In two adult skulls, the skull had a quadrangular shape, which we assumed to be correlated to the presence of an unusually interdigitated open metopic suture. We propose to name this anomaly: tetragonocephaly. Another presumed suture-related condition, bathrocephaly, was found concomitantly with basilar invagination in several cases. We hypothesize that the chronically raised intracranial pressure in these cases caused the still open lambdoidal sutures to distend and the occipital bone to protrude.

Malformations of the axial skeleton inMuseum Vrolik I: Homeotic transformations and numerical anomalies

The Museum Vrolik collection of anatomical specimens in Amsterdam, The Netherlands, comprises over 5,000 specimens of human and animal anatomy, embryology, pathology, and congenital anomalies. Recently, we rediagnosed a subset of the collection comprising dried human trunk skeletons and cranial base preparations presenting with homeotic transformations (vertebral phenotypic shifts) and numerical vertebral anomalies. We identified 11 trunk skeletons with either anterior or posterior homeotic transformations (AHT or PHT), 5 trunk skeletons with either less or more than the normal number of vertebrae, and well over a hundred cranial base preparations with either AHT (atlas-assimilation) or PHT (occipital vertebra). We found that, although homeotic transformations and numerical anomalies are distinct conditions, both can be described in terms of mismatch between homeotic patterning and morphological segmentation of the paraxial mesoderm. Therefore these two processes are perhaps not as tightly linked as they may seem on the basis of recent molecular studies. In homeotic transformations there is a constant mismatch between homeotic patterning and morphological segmentation throughout the affected region of the vertebral column. In numerical anomalies there is a variable mismatch between homeotic patterning and morphological segmentation, either because of stretching or squeezing of the homeotic pattern or because of oligo- or polysegmentation of the presomitic mesoderm (PSM). Homeotic transformations of the axial skeleton have an incidence of about 1%-5%, apart from their occurrence in malformation syndromes. Of the various etiological possibilities, explaining their frequent but mostly sporadic occurrence, maternal hyperthermia seems an attractive candidate.

Aspects of the history of osteogenesis imperfecta (Vrolik's syndrome)

Osteogenesis imperfecta (OI) or Vrolik's syndrome is a heterogeneous group of inherited conditions arising from a variety of biochemical and morphological collagen defects. It was Willem Vrolik, Professor of Anatomy, Pathological Anatomy and Zoology at the Athenaeum Illustre (University of Amsterdam), who described in his Handbook of Pathological Anatomy (1842-1844) and Tabulae ad illustrandam embryogenesin hominis et mammalium, naturalem tam abnormem (1844-1849) a newborn infant with numerous fractures and hydrocephalus. In the Tabulae, having both Latin and Dutch texts, in the Latin text Vrolik used in the heading of Plate 91 the term Osteogenesis imperfecta (in Dutch: gebrekkige beenwording). Vrolik also mentioned that the infant lived three days and that both the parents were suffering from lues universalis at the time of birth. On our reexamination, the whole skeleton appeared poorly mineralised. The fairly large skull exhibited a broad and high forehead, large fontanels, frontal and temporal bossing, shallow orbits, and a protruding occiput. The calvaria consisted of many Wormian bones. The tubular bones, although of normal length and only slightly curved, were very thin, as were the ribs. All the skeletal structures showed one or more fractures and many fractures showed callus formation. In 1998 we re-diagnosed the condition of the specimen as osteogenesis imperfecta type II. Willem Vrolik was one of the first to realize that many skeletal dysplasias were not the result of a postnatal acquired disease, such as "rickets" or "osteomalacia" as many of his contemporaries believed. He thought that it might be due to insufficient intrinsic "generative energy." He substantiated this by stating that in this specimen a primary impairment of ossification is present and not a secondary degeneration. The descriptions given by Willem Vrolik in some of the specimens generated the term Osteogenesis imperfecta and the eponym Vrolik's syndrome for this genetic disorder characterized by increased fragility.

Digital data and the 19th century teratology collection

The golden age of descriptive teratology (congenital anomalies) was between 1750 and 1850. During that period, the study of human congenital malformations, especially those dramatic examples designated as 'monsters', attracted special attention. One of the finest collections in this field was Museum Vrolikianum, the collection of father and son, Gerardus (1775-1859) and Willem Vrolik (1801-1863). Willem, a specialist in teratology, described many of these specimens in his Handbook of Pathological Anatomy (1844) and his teratology atlas Tabulae ad illustrandam embryogenesin hominis et mammaliam tam naturalem quam abnormem (1849). This collection is still an integral part of the Museum Vrolik in the Academic Medical Center in Amsterdam. From 1991 to 1994, the collection of congenital anomalies was re-catalogued and re-described according to contemporary syndromological views. We diagnosed rare syndromes with multiple congenital anomalies, rare skeletal dysplasias, closure defects of the neural tube and conjoined and acardiac twins. We came to the conclusion that some anomalies of the conditions diagnosed have been reported only a few times. Certain cases demonstrate relationships between different malformations, and provide critical 'missing links' in the teratological series. For the diagnosis of the clinical syndromes in some of the specimens magnetic resonance imaging (MRI), computed tomography (CT), spiral CT and radiographical techniques were of crucial importance and are discussed in this paper.

A 100-year-old anatomical specimen presenting with boomerang-like skeletal dysplasia: diagnostic strategies and outcome

The Museum Vrolik collection of human anatomy comprises 360 recently redescribed specimens with congenital anomalies. The specimen described here dated from 1881 and presented with a general embryonic appearance, disproportionate short stature, brachycephaly, widened cranial sutures, hypertelorism, microphthalmia, bilateral cleft lip and palate, micrognathia, short and curved limbs, polysyndactyly, and abnormal female genitalia. Conventional radiography was hampered by decalcification of the skeleton, due to acidification of the preservation fluid. The use of additional imaging techniques, i.e., mammography, computerized tomography with three-dimensional reconstruction, and magnetic resonance imaging eventually led us to conclude that the condition of our specimen was similar to Piepkorn type skeletal dysplasia, boomerang dysplasia, and a condition described by Carpenter and Hunter [1982: J Med Genet 19:311-315], though none of these diagnoses seemed fully applicable.

Congenital anomalies in the teratological collection of Museum Vrolik in Amsterdam, The Netherlands. III: primary field defects, sequences, and other complex anomalies

The Museum Vrolik collection of the Department of Anatomy and Embryology of the Academic Medical Center, University of Amsterdam, founded by Gerardus Vrolik (1775-1859) and his son Willem Vrolik (1801-1863), consists of more than 5,000 specimens of human and animal anatomy, embryology, pathology, and congenital anomalies. Recently, the collection of congenital anomalies, comprising 360 specimens, was recatalogued and redescribed according to contemporary morphogenetic views. The original descriptions, if preserved, were compared with the clinical, radiographical, and magnetic resonance imaging findings. In 120 specimens the following midline anomalies, primary field defects, and sequences were diagnosed: holoprosencephaly sequence; aprosencephaly/atelencephaly; cleft lip; Pierre Robin sequence; omphalocele; diaphragmatic hernia; ectopic heart; bladder exstrophy; cloacal exstrophy; caudal dysgenesis; prune belly sequence; sirenomelia; fetal akinesia sequence; and disruption sequences. Polytopic field defects and associations were diagnosed in 25 specimens. We discuss the opinions of Gerardus and Willem Vrolik, who tried to find reasonable explanations for the dysmorphogenetic entities they investigated, rather than accepting the traditional superstitions.