Canal neuromast position prefigures developmental patterning of the suborbital bone series in Astyanax cave- and surface-dwelling fish.

Developmental patterning is a complex biological phenomenon, involving integrated cellular and molecular signaling across diverse tissues. In Astyanax cavefish, the lateral line sensory system is dramatically expanded in a region of the cranium marked by significant bone abnormalities. This system provides the opportunity to understand how facial bone patterning can become altered through sensory system changes. Here we investigate a classic postulation that mechanosensory receptor neuromasts seed intramembranous facial bones in aquatic vertebrates. Using an in vivo staining procedure across individual life history, we observed infraorbital canal neuromasts serving as sites of ossification for suborbital bones. The manner in which cavefish departed from the stereotypical and symmetrical canal neuromast patterns of closely-related surface-dwelling fish were associated with specific changes to the suborbital bone complex. For instance, bony fusion, rarely observed in surface fish, was associated with shorter distances between canal neuromasts in cavefish, suggesting that closer canal neuromasts result in bony fusions. Additionally, cavefish lacking the sixth suborbital bone (SO6) uniformly lacked the associated (sixth) canal neuromast. This study suggests that patterning of canal neuromasts may impact spatial position of suborbital bones across development. The absence of an eye and subsequent orbital collapse in cavefish appears to influence positional information normally inherent to the infraorbital canal. These alterations result in coordinated changes to adult neuromast and bone structures. This work highlights complex interactions between visual, sensory and bony tissues during development that explain certain abnormal craniofacial features in cavefish.

Determination of the gestational age through ultrasound measurements of some uterine and foetal parameters in Bulgarian local goats.

The aim of the current study was to determine the gestational age in goats through the measurement of some foetal and uterine structures. Twenty-four pregnant Bulgarian local goats were submitted to ultrasound foetometry by transrectal and transabdominal approaches. Ultrasound measurement of studied parameters was done at 7-day intervals during the first trimester of gestation (days 21-49) and at 14-day intervals between gestation days 49 and 133. Associations of foetometry data with foetal age were investigated by linear (y = a + bx), quadratic (y = ax2  + bx + c) and exponential (y = axn ) equations. According to the results, some biometric parameters (uterine lumen diameter, crown-rump length, trunk diameter, biparietal diameter, foetal aortic diameter) exhibited a stronger correlation to gestational age (R2  ≥ 0.90) and lower standard error of the estimate (SEE ≤ 8) as compared to foetal eye orbit diameter, and outer and inner placentome diameters (R2  ≤ 0.90; SEE ≥ 8). Each of these biometric parameters could be measured in different periods of gestation, thus allowing for monitoring and determination of foetal age at almost all stages of pregnancy.

Embryologic and Fetal Development of the Human Orbit.

PURPOSE: To review the recent data about orbital development and sort out the controversies from the very early stages during embryonic life till final maturation of the orbit late in fetal life, and to appreciate the morphogenesis of all the definitive structures in the orbit in a methodical and timely fashion. METHODS: The authors extensively review major studies detailing every aspect of human embryologic and fetal orbital morphogenesis including the development of extraocular muscles, orbital fat, vessels, nerves, and the supportive connective tissue framework as well as bone. These interdisciplinary studies span almost a century and a half, and include some significant controversial opposing points of view which the authors hopefully sort out. The authors also highlight a few of the most noteworthy molecular biologic studies regarding the multiple and interacting signaling pathways involved in regulating normal orbital morphogenesis. RESULTS: Orbital morphogenesis involves a successive series of subtle yet tightly regulated morphogenetic events that could only be explained through the chronological narrative used by the authors. The processes that trigger and contribute to the formation of the orbits are complex and seem to be intricately regulated by multifaceted interactions and bidirectional cross-talk between a multitude of cellular building raw materials including the developing optic vesicles, neuroectoderm, cranial neural crest cells and mesoderm. CONCLUSIONS: Development of the orbit is a collective enterprise necessitating interactions between, as well as contributions from different cell populations both within and beyond the realm of the orbit. A basic understanding of the processes underlying orbital ontogenesis is a crucial first step toward establishing a genetic basis or an embryologic link with orbital disease.

Dynamics of optic canal and orbital cavity development revealed by microCT.

PURPOSE: Numerous studies have attempted to clarify the exact anatomy and variations of the optic canal with non-conclusive results due to its close proximity to many vulnerable structures. We sought to determine the dynamics of growth and development of these structures on fetal skulls, which will help us to better understand of gender and age-dependent variations, as well as fatal malformations. METHODS: Fifteen previously macerated fetal frontal and sphenoid bones were analyzed and the diameters of optic canal, and distance of orbit from frontomaxillary suture to frontozygomatic suture were measured using 3D reconstruction images obtained by micro-CT. RESULTS: Average diameter of the optic canal in 300 mm fetus was measured to be 1,546 ± 36 µm, in 400 mm fetus 2,470 ± 123 µm and in 500 mm fetus 3,757 ± 203 µm. This trend indicates a linear enlargement of optic canal during the fetal period. During the same time period, diameter of the orbit enlarges from 12,319 ± 559 µm in 300 mm fetus to 19,788 ± 736 µm in 500 mm fetus. Growth curve is significantly lower in comparison with the same curve in optic canal data. We also calculated the ratio of orbit diameter and optic canal diameter between those groups which decreased from a value of 7.9 ± 0.4 for 300 mm fetus to 5.3 ± 0.2 for 500 mm fetus. CONCLUSION: Dynamics of optic canal and orbital cavity development is different in early and late fetal period. Diameters of those structures are in better correlation with the fetal length.

Fetal interlens distance: normal values during pregnancy.

OBJECTIVES: The aims of this study were to establish normal ranges of values for interlens distance (ILD) during gestation, and to assess the correlation between ILD and growth of the orbits and other fetal biometric parameters. METHODS: A cross-sectional study of morphologically normal, singleton fetuses was carried out in low-risk pregnant women. We measured the distance between the centers of the fetal lenses from 12 to 37 completed weeks of gestation. An oblique anterior coronal section was used to measure the ILD. The biorbital diameter (BOD) was measured in the same plane. We analyzed the correlation between the ILD and gestational age (GA), BOD, biparietal diameter (BPD), head circumference (HC), femur length (FL) and abdominal circumference (AC). Fetal gender was assessed to evaluate possible significant differences. RESULTS: Four hundred and fifty normal fetuses were recruited for the study. In 427 fetuses appropriate ILD measurements were obtained, and complete evaluation of all parameters was accomplished in 377 of these. ILD demonstrated a high positive correlation with GA (r(2) = 0.969), BPD (r(2) = 0.959), HC (r(2) = 0.962), AC (r(2) = 0.949) and FL (r(2) = 0.956) as pregnancy advanced. The mean BOD : ILD ratio was 1.50 +/- 0.08, remaining constant throughout pregnancy (linear regression r(2) = 0.006). No statistically significant differences were found between genders for mean ILD and GA of the study population (P = 0.604 and 0.595, respectively). CONCLUSIONS: The results of this study confirm previous hypotheses regarding the close relationship between eyeball growth and growth of the surrounding bony structures. Measurement of fetal ILD, which can be used interchangeably with BOD measurement in either the axial or coronal plane, can be taken to reflect the expected development of the fetal orbits whilst simultaneously providing valuable information on eyeball development. It is likely that ILD could be used as a complementary tool in the elaboration of various severe abnormalities, mainly related to craniofacial and nervous system malformations.

Examination of the Annular Tendon (Annulus of Zinn) as a Common Origin of the Extraocular Rectus Muscles: 2. Embryological Basis of Extraocular Muscles Anomalies.

Purpose: Many reports have described anomalous connections of the superior rectus (SR) with other extraocular rectus muscles, in which additional heads of the other three rectus muscles likely provided the connections. We examined how these connections are established during fetal development. Methods: We analyzed paraffin-embedded horizontal sections from 25 late-stage fetuses. Horizontal sections are best suited for understanding the mediolateral relationships of muscle origins. Results: We confirmed a common tendinous origin of the lateral rectus (LR), inferior rectus (IR) and medial rectus (MR) muscles that was separated from the SR origin. Notably, eight fetuses (32%) had tendinous or muscular connections between the SR and other rectus muscles that had one of four morphologies: (a) a thin tendon from the SR to the common tendon of the three rectus muscles (2 fetuses), (b) a thin tendon to the LR (one fetus), (c) a thin tendon to the inferior rectus muscle origin (two fetuses), and (d) SR muscle fibers arising from an additional head of the LR (three fetuses). Conclusions: The SR seemed to issue a thin tendon that passed along the inferior or lateral side of the oculomotor nerve. Conversely, the LR and inferior rectus muscle were likely to carry a supernumerary bundle that reached the SR. The accessory head of the medial rectus muscle showed a stable morphology in that it seemed to also provide an anomalous double head. However, the presence of an accessory head in the LR was rare. In contrast with our previously published diagram of the orbital apex, the accessory head of the medial rectus muscle passed along the lateral side of the superior oblique.

A biometric study of the fetal orbit and lens in normal pregnancies.

PURPOSE: To construct nomograms of the size of the fetal orbit and lens and to evaluate the relationships between the gestational age and the biometry of the fetal orbit and lens. METHOD: Six hundred two normal pregnant women were evaluated from 15 to 40 weeks of gestation. Fetal orbital and lens measurements were added to routine biometric measurements for normal fetuses. RESULTS: A total of 595 measurements were used for analyses. A strong linear correlation was observed between gestational age and orbital diameter, orbital circumference, and orbital surface. A linear correlation was also found between gestational age and lens diameter, lens circumference, and lens surface. A linear growth function was observed between biparietal diameter and both the orbital diameter and the lens diameter. CONCLUSION: Orbital and lens measurements provide data that correlate with fetal growth and development. These data may also help detect fetal ocular abnormalities.

Orbital asymmetry in development: an anatomical study.

The aim of this study was to analyze the human orbital asymmetry during development. One hundred twenty-seven identified human dry skulls, with sex, age, date and cause of death record, in good preservation state, were used. Bones that had evidence of trauma, malformations or other pathology were excluded. The sample was divided into 4 age groups: I--intra-uterine life (n=20), II--newborn up to 2 years old (n=43), III--three up to 20 years old (n=27) and IV--21 up to 76 years old (n=37). The skulls were photographed in normal frontalis and images were analyzed with the software AutoCAD 2002 in real scale. The obtained measurements were: greater horizontal diameter (HD), greater vertical diameter (VD), orbital perimeter and orbital base area. All skulls showed asymmetry in all measures, except 4 of them that showed symmetry in VD and perimeter. The asymmetry occurred in all ages, being calculated as a percent rate for VD--2.73%, HD--4.48%, area--4.77% and perimeter--2.47%. There was predominance in asymmetric rate in female skulls and only in the group II the difference between gender was statistically significant (p<0.05). The right orbit presented larger measures. The asymmetric rate was assumed as the normal anatomic pattern.

A regression model including fetal orbit measurements to predict parturition in Standardbred mares with normal pregnancy.

In the mare, foaling is a critical unpredictable event due to a wide range of gestational length and the absence of clear signs of impending parturition. To predict foaling, pH, inversion sodium potassium and increase of calcium concentration in mammary secretions are used. The aim of this study was to find how many days are left until parturition knowing mare's age (A) and parity (P) combined with ultrasonographic measurements of the fetal orbit in Standardbred mares with normal pregnancy. Eighty healthy Standardbred mares with normal pregnancy were hospitalized for attended delivery. Information about mare's age, parity and breeding date were recorded at admission. Transrectal ultrasonography were routinely performed at admission and every 10 days until parturition using a B-mode real time portable unit equipped with a 5-7.5 MHz linear transducer. The images of the fetal orbit were acquired when cornea, anterior and posterior chamber, vitreous body, lens and optic nerve were visible. Longitudinal diameter (LD) was considered as the distance between the two ocular poles, within the vitreous body; transverse diameter (TD), perpendicular to LD and bisecting the lens, was measured as the distance between cornea and retina. At delivery, length of pregnancy and gestational age at each exam were registered. For each ultrasound examination, days before parturition (DBP) were calculated. Seventy-eight Standardbred mares with normal pregnancies were included in the study. Mares' mean age was 9 ±â€¯5 years old (range 4-20 years) and mean gestation length was 341 ±â€¯7 days (range 327-366 days). Thirty-three mares were primiparous and 45 mares were multiparous. Data were analyzed using a regression tree: P, A, LD and TD were used as covariates. DBP was used as the variable of interest. Nine terminal nodes were identified based on the selected covariates. The first split is produced by the TD: fetuses with TD greater or equal than 2.97 cm are further split according to LD, with a threshold of 3.28 cm. The next split is dictated by A; after a further split on LD, the first terminal node is built, containing 34 fetuses with average DBP equal to 10 days. If the A is ≥ 9.5 years a further split is on P: when mares are multiparous, the TD built two different nodes. Since prediction of mare's foaling date is an important factor in stud farm management, the regression model developed may help the veterinarian to estimate the DBP in Standardbred mares with normal pregnancy.

Examination of the Topographical Anatomy and Fetal Development of the Tendinous Annulus of Zinn for a Common Origin of the Extraocular Recti.

Purpose: The aim was to clarify the topographical anatomy of the common tendinous ring for the four rectus muscles in both adults and fetuses. Methods: We histologically examined the annular ligament for a common origin of the extraocular rectus muscles using 10 specimens from elderly individuals and 31 embryonic and fetal specimens. Results: At 6 to 8 weeks, each rectus carried an independent long tendon, individually originating from the sphenoid. Notably, we found additional origins from the optic or oculomotor nerve sheath. At 12 to 15 weeks, the lateral, inferior, and medial recti muscles were united to provide a C-shaped musculofibrous mass that was separated from the superior rectus originating from the edge of the optic canal opening. Morphologic features at 31 to 38 weeks were almost the same as those at 12 to 15 weeks, but the long and thick common tendon of the three recti reached the sphenoid body in the parasellar area. In adults, a ring-like arrangement of the rectus muscles ended at a site 8.1 to 12.0 mm anterior to the optic canal opening and independent of the superior rectus origin, the lateral, inferior, and medial recti formed a C-shaped muscle mass. The united origins of the three recti changed to a fibrous band extending along the superomedial wall of the orbital fissure. Conclusions: Consequently, none of the specimens we examined exhibited an annular tendon representing a common origin of the four recti, suggesting that the common tendinous ring includes only medial, lateral, and inferior rectus muscles with the superior rectus taking its origin independently.

The caroticoclinoid foramen in fetal and infantile orbitosphenoid, presphenoid, and sphenoid bones: developmental and neurosurgical considerations.

OBJECTIVEThe presence of a caroticoclinoid foramen may increase the likelihood of adverse neurosurgical events. Despite the clinical importance of the caroticoclinoid foramen, its study has been mostly limited to adult populations. Therefore, the object of this study was to describe the prevalence, morphology, and development of the caroticoclinoid foramen among varied sexes and races in early life.METHODSThe study analyzed caroticoclinoid foramina in dry orbitosphenoid, presphenoid, and sphenoid bones from a population of 101 fetal and infantile crania of varied sex and race.RESULTSA caroticoclinoid foramen, whether complete, near complete, or partial, was found in 36 of 199 sides (18.1%). Of the 98 crania with bilaterally intact sides, 21 (21.4%) had the presence of at least one caroticoclinoid foramen. Caroticoclinoid foramina were found unilaterally and bilaterally, in both female and male crania (9/41, 22.0%; 12/57, 21.1%, respectively) and, likewise, in crania of both black and white races (9/54, 16.7%; 12/44, 27.3%, respectively). Caroticoclinoid foramina were formed from cornuate bony projections from the anterior clinoid process, middle clinoid process, or both anterior and middle clinoid processes. Caroticoclinoid foramina were also found in isolated orbitosphenoid bones from individuals as young as 4 months' fetal age.CONCLUSIONSThe caroticoclinoid foramen occurs in approximately one of every 5 sides and in one in every 5 individuals of perinatal age and should, therefore, be considered a common finding in both fetuses and infants. It is common in both females and males as well as in both black and white races, alike. Furthermore, the caroticoclinoid foramen can be found in individuals as young as 4 months of fetal age. Failure to anticipate the presence of a caroticoclinoid foramen will place important neurovascular structures, including the internal carotid artery, at risk of injury. Neurosurgeons should, therefore, anticipate the caroticoclinoid foramen even in their youngest patients.

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.

High frequency ultrasound imaging of the growth and development of the normal chick embryo.

The purpose of this study is to delineate with high frequency ultrasound imaging the normal growth and development of the chick embryo throughout its incubation period. White Leghorn chick embryos were imaged through an opening in the egg air cell from incubation day 0-19 (Hamburger & Hamilton stage 1-45) using a 13 MHz clinical high frequency linear small parts transducer. Multiple anatomic growth parameters were measured. Normal growth was confirmed with Hamburger and Hamilton staging. A timeline was constructed showing when each anatomic growth parameter could be visualized. Means and standard deviations of each parameter were plotted against incubation days studied to create nomograms and numerical tables of normal growth and development of the chick embryo. With this set of data, abnormal growth and development of the chick embryo can now be assessed.

Early and late onset fetal microphthalmia.

OBJECTIVE: The purpose of this study was to present sonographic and pathologic findings in early and late onset fetal microphthalmia. STUDY DESIGN: Fetal sonography was prospectively performed in 30,989 consecutive pregnancies at 14 to 24 weeks' gestation. In addition, we retrospectively reevaluated US recordings of 4 fetuses from other hospitals, in which normal eyes were observed in early and midgestation and microphthalmia was diagnosed only in the third trimester of pregnancy or after birth. RESULTS: Microphthalmia was detected in 13 fetuses in the prospective group. Twelve of 13 had additional structural and chromosomal anomalies. Termination of pregnancy was performed in 12 cases. In the retrospective group of late onset microphthalmia we confirmed the normal eye measurements performed in the early and midpregnancy. Severe vision impairment or blindness was noted in 3 of these children, while the fourth pregnancy was terminated. CONCLUSION: Normal measurements of the fetal eyes in early and midpregnancy do not exclude the possibility of subsequent development of microphthalmia.

The prenatal development of the human orbit.

During the 1970s, as part of his work for a doctor's thesis in which he described the development of the human orbit in great detail, the first author established the largest anatomical collection of embryonic and fetal orbits ever. Unfortunately, he died before the thesis could be finished. The thousands of sections have now been scanned at high resolution and made publicly available on the Internet at www.visible-orbit.org; 3-D reconstruction software is being developed. The Discussion and part of the 'Methods' section of this thesis are published in translation in this article. The conclusions of the first author at the time read as follows: (1) initially, the developing orbit is vaguely indicated by condensations in the mesenchymal connective tissue area; (2) in this connective tissue area, chondral, osseous and muscular structures develop and grow until, in the fully developed stage, the orbital content is surrounded by bony surfaces with a thin layer of connective tissue as periosteum, and by a muscle fragment; (3) the embryonic and early fetal phase, during which one can only speak of a 'regio orbitalis,' is followed by a period in which we can speak of a primordial orbit; (4) the phase of the primordial orbit extends until after birth; (5) the surface area of all orbital walls increases more or less linearly; (6) the 'musculus orbitalis Mülleri' occupies a special place in the orbital wall; (7) the so-called 'regio craniolateralis' is the primordium, which, in the fully developed stage, is occupied by the thick intersection of the frontolateral and the horizontal part of the frontal bone; (8) in the frontal plane, the shape of the primordial orbit, as well as that of the fully developed orbit, is more or less round; (9) the prenatal development of an eye socket is a complex event, characterized by changes in composition, shape and size of the orbital wall; and (10) the orbit can only be denoted by the term "eye socket" when it is fully developed. At the end of the thesis, he also presented the following postulates: (1) in the prenatal orbit, the development of the so-called 'periorbita' is at the forefront; (2) the mutual rotation of the orbital axes and the frontalization of the eyes from approx. 180 degrees in the early prenatal stages to approx. 50 degrees in adulthood do not seem to be caused by mechanical influences of the surrounding tissue; (3) the pterygopalatine fossa and the 'cavum cerebri' are not part of the orbit at any developmental stage; (4) in the prenatal skull, the inferior nasal concha, which forms part of the maxilla in the fully developed skull, is part of the 'capsula nasalis'; and (5) in order to achieve normal development of the eye socket in microphthalmus and anophthalmus, the normal orbital content should be restored.

Transabdominal and transrectal ultrasonography of fetuses in Württemberg ewes: Correlation with gestational age.

It is useful to determine the gestational age in sheep to provide essential information for effective flock management practices. The aims of this study were to evaluate the efficacy and practical aspects for using two ultrasound techniques, transabdominal and transrectal, in determining the gestational age in Württemberg ewes. Monitoring of embryo and fetus developmental stages during the ewes' gestation was carried out with real time ultrasound using a transabdominal convex probe, frequency 3.5 MHz, and a transrectal linear probe, frequency 7.5 MHz. The size of the embryonic vesicle during the period from the 23rd to the 38th day of gestation can be used as a confirmational indicator of gestational age when the transrectal probe is used. The occipital nasal diameter correlated with the gestational age with both transabdominal (P < 0.05) and transrectal probes (P < 0.01) from the 46th to the 63rd day of gestation. The biparietal diameter of the fetal head measured by transabdominal probe during the period from the 46th to the 63rd day of gestation correlates with gestation age (P < 0.05). The diameter of the fetal eye orbit monitored by transrectal probe from the 46th to the 63rd day of gestation also correlated well with gestational age (P < 0.05).

Expression of FGFR-2 and FGFR-3 in the normal human fetal orbit.

AIMS: To demonstrate the expression patterns of two fibroblast growth factor receptors (FGFR-2 and FGFR-3) in the normal human fetal orbit. METHODS: 6 microm orbital slide sections were prepared from 12 week old human fetal material obtained within established ethical guidelines. Radioactive in situ hybridisation techniques were used to demonstrate the expression patterns of FGFR-2 and FGFR-3 within these sections. Only one foetus had appropriate orbital sections taken. RESULTS: FGFR-2 was expressed within the extraocular muscles (EOMs) and the optic nerve sheath and to a lesser degree within the orbital periosteal margins and the cranial sutures. FGFR-3 was expressed a lot within the periosteal margins and cranial sutures but not within either the EOMs or the optic nerve sheath. CONCLUSIONS: FGFR-2 and FGFR-3 are differentially expressed within different orbital components. FGFR-2 gene mutations may be responsible for craniosynostotic syndromes such as Crouzon, Pfeiffer, and Apert, while those in the FGFR-3 gene may cause isolated unicoronal synostosis. EOMs may be histologically abnormal in cases of Apert, Pfeiffer, and Crouzon syndromes but not isolated unicoronal synostosis. The pattern of expression of FGFR-2 in the normal human fetal orbit may explain some of the EOM histological findings seen in some cases of Apert, Pfeiffer, and Crouzon syndromes.

A biometric study of the eye, orbit, and face in 205 normal human fetuses.

PURPOSE: To develop models for assessing the differential growth of the fetal face along its horizontal and vertical axes, as well as of the orbit and the eye. METHODS: Normal human fetuses (n = 205), whose gestational ages ranged from 15.5 to 41 weeks of amenorrhea, were examined. Orbitofacial parameters were as follows: outer canthal distance, inner canthal distance, palpebral fissure length, and oropalpebral distance. Ocular parameters were corneal diameter and axial length. Correlations were tested among all parameters. Linear and polynomial regression analyses of gestational age and the orbitofacial and ocular parameters were used to develop models of growth. Differential patterns of growth in the face were investigated. RESULTS: The best correlation was found between palpebral fissure length and oropalpebral distance. The increase of each of the parameters studied could be accurately described by a linear model. Sex had no detectable effect on these parameters. Compared with the skull, the face had a more rapid growth along the vertical axis. The palpebral fissure developed more rapidly than the eye. CONCLUSIONS: The parameters that were studied in the fetal face, orbit, and eye follow a roughly linear growth curve.

In vivo imaging of embryonic development in the mouse eye by ultrasound biomicroscopy.

PURPOSE: New imaging tools now provide an unprecedented opportunity to visualize anatomic and functional development of the mouse eye. In this study, normal embryonic development of the mouse eye was studied by ultrasound biomicroscopy (UBM), with a focus on the formation of the retina, lens, and cornea. METHODS: The growth of 65 embryonic eyes from timed-pregnant CD-1 mice was examined at various stages of development between embryonic day (E)11.5 and E18.5, using 40-MHz UBM. RESULTS: The morphogenesis of ocular tissues including the lens, retina, and orbit were revealed from the earliest stages of development. The major axis of the CD-1 lens grows at a rate of 68 micro m/d, whereas that of the globe grows at a rate of 122 microm/d, with a concomitant exponential increase in volume. CONCLUSIONS: UBM allows noninvasive assessment of ocular morphogenesis in vivo and can be used to calculate relative growth rates of ocular structures.

Congenital craniofacial anomalies of ophthalmic importance.

Congenital craniofacial abnormalities frequently require ophthalmic evaluation and surgical management. Called upon to perform as part of the craniofacial team managing the often severely deformed craniofacial patient, the ophthalmologist must bring a basic knowledge of craniofacial syndromes and developmental anatomy, as well as clinical acumen to help preserve or improve ocular and adnexal function. As an introduction to this area of ophthalmology, the clinical features, classification, appropriate facial embryology, assessment and surgical considerations of the various congenital craniofacial abnormalities are reviewed. The expanding availability of craniofacial surgeons and surgical teams along with improved surgical results will ultimately require an increasing involvement by many more ophthalmologists in the evaluation and management of these congenital abnormalities.