Partial congenital arrhinia: never seen before adult presentation.

BACKGROUND: Arrhinia is defined as the partial or complete absence of the nasal structures. It is a defect of embryonal origin and can be seen in association with other craniofacial anomalies, central nervous system anomalies, absence of paranasal sinuses, and other palatal and ocular abnormalities. Very few patients with arrhinia have been reported so far in the history of modern medicine. CASE REPORT: This study reports an adult patient with congenital partial arrhinia and reviews the literature along with the embryological basis of such a rare disease. CONCLUSION: Arrhinia is a medical condition with scarce documentation in the literature. This article presents the clinical as well as radiological features of this rare entity.

Ontogenesis of the tear drainage system requires Prickle1-driven polarized basement membrane deposition.

In terrestrial animals, the lacrimal drainage apparatus evolved to serve as conduits for tear flow; however, little is known about the ontogenesis of this system. Here, we define the anatomy of the fully formed tear duct in mice, characterize crucial morphogenetic events for the development of tear duct components and identify the site for primordial tear duct (PTD) initiation. We report that the PTD originates from the orbital lacrimal lamina, a junction formed by the epithelia of the maxillary and lateral nasal processes. We demonstrate that Prickle1, a key component of planar cell polarity signaling, is expressed in progenitors of the PTD and throughout tear duct morphogenesis. Disruption of Prickle1 stalls tear duct elongation; in particular, the loss of basement membrane deposition and aberrant cytoplasmic accumulation of laminin are salient. Altered cell adhesion, cytoskeletal transport systems, vesicular transport systems and cell axis orientation in Prickle1 mutants support the role of Prickle1 in planar cell polarity. Taken together, our results highlight a crucial role of Prickle1-mediated polarized basement membrane secretion and deposition in PTD elongation.

Ontogeny of the Orbital Glands and Their Environs in the Pantropical Spotted Dolphin (Stenella attenuata: Delphinidae).

The nasolacrimal duct (NLD) connects the orbital (often associated with the Deep Anterior Orbital gland: DAOG, a.k.a. Harderian gland) and nasal regions in many tetrapods. Adult cetaceans are usually said to lack an NLD, and there is little agreement in the literature concerning the identity of their orbital glands, which may reflect conflicting definitions rather than taxonomic variation. In this study, we examined an embryological series of the pantropical spotted dolphin (Stenella attenuata), and report numerous divergences from other tetrapods. Underdeveloped eyelids and a few ventral orbital glands are present by late Stage (S) 17. By S 19, circumorbital conjunctival glands are present. In S 20, these conjunctival glands have proliferated, eyelids (and scattered palpebral glands) have formed, and a duct similar to the NLD has appeared. Subsequently, both the palpebral glands and the NLD are progressively reduced by S 22, even as the conjunctival glands exhibit regional growth. In most tetrapods examined, the ontogeny of the NLD follows a series of three stages: Inception of NLD, Connection of orbit and nasal cavity by the NLD and Ossification (i.e., formation of the bony canal surrounding the NLD, emerging into the orbit via the lacrimal foramen in the lacrimal bone). In contrast, the dolphin NLD originates at the same time as the lacrimal bone, and a lacrimal foramen fails to develop. The cetacean fossil record shows that a lacrimal foramen was present in the earliest ancestral amphibious, freshwater forms, but was soon lost as the lineage invaded the oceans. Anat Rec, 2017. © 2017 Wiley Periodicals, Inc. Anat Rec, 301:77-87, 2018. © 2017 Wiley Periodicals, Inc.

Nasolacrimal duct opening to the inferior nasal meatus in human fetuses.

The purpose of this study is to describe the Hasner's membrane which is the main factor of congenital nasolacrimal duct obstruction. Hasner's membrane at the nasal end of the fetal nasolacrimal duct (NLD) is considered to rupture at and after birth. However, topographical anatomy around the membrane as well as a mechanism of rupture seems to be still obscure. We observed frontal or sagittal sections of 20 late-stage fetuses (28-33 weeks) and found the on-going rupture in 2 specimens. The present sections demonstrated that 1) the nasal dilation was not a simple ball-like structure but extended posteriorly and laterally; 2) dilation of the NLD consistently involved the lacrimal sac; 3) Hasner's membrane and ductal mucosal layer contained no macrophages and no or few arteries and nerves. The posterior extension of the NLD end ranged from 1-2 mm, while the lateral extension 3-5 mm although a site of the thinnest membrane varied in location between specimens. Moreover, the thickest NLD due to dilation was in the slightly orbital or upper side of the nasal end. Therefore, before surgical treatment of Hasner's membrane, evaluation using medical images seems to be necessary. Since the nasal epithelium on Hasner's membrane was most likely to destroy earlier than the NLD mucosal lining, observations of the membrane from the nasal cavity seemed helpful for diagnosis at which site would be broken and when.

Magnetic resonance imaging of the fetal efferent lacrimal pathways.

OBJECTIVE: To study the prenatal development of the efferent lacrimal pathways with magnetic resonance imaging (MRI), with special reference to the pathogenesis of congenital dacryocystoceles (CDCCs). METHODS: A total of 751 MRI studies of singleton fetuses [19-40 gestational weeks (GW)] were retrospectively evaluated. Visibility of the efferent lacrimal pathways was assessed on high-resolution T2-weighted sequences and the maximum transverse lacrimal sac diameter was recorded. RESULTS: Fluid-filled lacrimal sacs/nasolacrimal ducts could be demonstrated in 31.7% of fetuses, either unilaterally (50.6%) or bilaterally (49.4%). Visualization was age-dependent: demonstration frequency increased from 24 to 32 GW (60%) and decreased until term. Lacrimal sac diameters varied between 1.9 and 10.5 mm, but showed no correlation with gestational age. Lacrimal sacs with diameters >5 mm were considered to represent CDDC and were found in 2.76% of third-trimester fetuses. CONCLUSION: Fluid-filled efferent lacrimal pathways are a normal finding depending on gestational age. Visualization reflects the effect of two processes that occur over a protracted period of time: opening of the eyelids and lacrimal puncta, and the opening of the Hasner's membrane. Establishing the normal dimensions of the relatively large fetal lacrimal sacs allowed CDCC to be defined and showed a 2.76% incidence of CDCC in third-trimester fetuses.

Apoptosis as a creative agent of embryonic development of bucca, mentum and nasolacrimal duct. An in vivo study in rats.

INTRODUCTION: For embryonal facial development several fusion processes between different facial prominences are necessary. If fusion fails to appear, various facial clefts may occur, known as median (e.g. lower median cleft lip), oblique (e.g. open nasolacrimal duct) or lateral facial clefts (macrostomia, lateral cleft). MATERIAL AND METHODS: The development of 3 different facial regions (bucca, mentum, and nasolacrimal duct) was examined in rats using serial histological sections on day 13.5 after conception. Common procedures were used (staining for active caspase-3 and for Ki-67) for histological assessment about the role of apoptotic and proliferative processes in the fusion zones of buccal, mental and nasolacrimal areas. RESULTS: Multiple apoptotic events were detected in epithelial cells of the respective regions, the proliferative centers were located in the mesenchymal surroundings of fusion zones. CONCLUSION: A substantial precondition for fusion of facial prominences are proliferative and apoptotic processes in epithelial and mesenchymal cells. Apoptosis contributes to the development of bucca, mentum and the nasolacrimal duct. Absence of apoptoses may be responsible for facial clefts.

Congenital lower nasolacrimal duct anomaly: a case report.

A congenital anomaly of the nasolacrimal system not previously described is reported. The apposition of the distal end of the nasolacrimal duct was not with the nasal cavity as normally occurs prior to birth but to the external skin. As a result the child presented with difficulty with tear drainage and consequent infection--"neonatal conjunctivitis" followed by a facial abscess at the left lower border of the nose. Recent embryological studies suggest that this anomaly is due to failure of complete separation and migration of the epithelial rod most distal from the surface ectoderm to the inferior meatus of the nasal cavity. This distal remnant of the nasolacrimal duct thus remains juxtaposed to the surface ectoderm of the face on the lateral aspect of the alar nares. The modern concept of the embryological development of the nasolacrimal system is reviewed.

Incontinentia pigmenti associated with nasolacrimal duct obstruction.

A case is reported of a five-month-old female with incontinentia pigmenti associated with nasolacrimal duct obstruction. Ocular manifestations of incontinentia pigmenti have previously been described to include persistent hyperplastic primary vitreous, retinal dysplasia, retrolental fibroplasia, corneal opacities, cataract, optic atrophy, and strabismus. This case is believed to be the first reported instance of incontinentia pigmenti associated with nasolacrimal duct obstruction. The management of this patient is also discussed.

[Embryologic study of the lacrimal ducts in man. Apropos of 10 cases]. / Etude embryologique des voies lacrymales chez l'homme. A propos de dix cas.

The embryology of the human lacrimal system is not clearly defined in the literature and two hypotheses exist: the first suggests that the origin of the lacrimal system is from an ectodermal fold forming a sulcus of the naso-optic fissure. The second, with few defenders, describes the first rod of cells as meeting a second one which appears to emerge from the primitive nasal cavity. A study of ten human embryos, aged from 14 to 25 weeks and with a length of 12 to 33 cm, examined by histologic sections of 10 microns, revealed no lacrimal origin in the primitive nasal cavity near the inferior meatus. A further interesting point was that in three of the four embryos aged four months the lacrimal point was opened. Most authors, however, found the lacrimal sac and the nasolacrimal duct to be dilated, especially in one case where the inferior part of the nasolacrimal duct at the ostium below the inferior turbinate and meatus was widely dilated. In all the cases, the lower end of the duct was separated from the nasal cavity by a fine membrane in opposition with the nasal mucosa.

Development and congenital abnormalities of the nasolacrimal apparatus.

The development of the nasolacrimal apparatus was reassessed based on the examination of serial sections done in 27 (54 orbits) embryos and fetuses ranging in size from 13.6 mm to term. In addition two adult specimens were examined. The entire nasolacrimal apparatus viz. canaliculi, lacrimal sac, and nasolacrimal duct develop contemporaneously. Canalization thereafter occurs throughout its length at the same time. The epithelium which lines the nasolacrimal apparatus abuts against the conjunctival epithelium superiorly in relationship to the puncta and the nasal mucosa at the opening of the nasolacrimal duct. These gossamer-like membranes perforate at term or soon thereafter. With the development of the face, the maxillary process grows medially to abut against, and then to override, the paraxial mesoderm of the nasolacrimal process. The nasooptic fissure is thus formed between these two mesodermal complexes. The surface ectoderm within the fissure thickens in a cord-like fashion and this is the analaga of the nasolacrimal apparatus. There is divergence of opinion as to the subsequent development of tear drainage system. A cord of epithelial cells forms from the nasal cavity and grows cephalad to become continuous with the main cord of buried surface ectoderm (Figure 1). It has been contended by Duke-Elder that the main epithelial cord then sends extensions laterally to form the superior and the inferior canaliculi. The inferior canaliculus extends more laterally than the superior canaliculus. At 3 months' development, canalization of the nasolacrimal apparatus is purported to occur in a segmental manner. These cavities then coalesce in a haphazard manner, finally forming a continuous tube. It is also suggested that the main core of buried epithelium canalizes from cephal caudalwards and that the epithelium arising from the nasal cavity canalizes in a reverse direction. The lacrimal sac then expands: the canaliculi canalize and the final section of the nasolacrimal duct to become patent is the opening into the inferior meatus of the nose below the inferior meatus of the nose below the inferior turbinate.U

[Differentiation in vitro of the nasolacrymal canal of Discoglossus pictus Otth (anuran amphibian)]. / Différenciation in vitro du canal nasolacrymal de Discoglossus pictus Otth (Amphibien Anoure)

The nasolacrymal duct of Discoglossus pictus is able to differentiate in vitro from prometamorphosis, without thyroxine added to the culture medium if it is taken off late or with thyroxine added to the culture medium if it is taken off earlier (presumptive anlage).