The pattern of the thoracic splanchnic nerves as they pass through the diaphragm.

The formation and structure of the greater, lesser, and least thoracic splanchnic nerves is highly variable in their intrathoracic as well as their subdiaphragmatic portion. Splanchnicectomies for pain control of otherwise intractable upper abdominal pain and other surgical procedures are dependent on the detailed knowledge of the anatomy of these nerves and their variations. Many commonly used anatomical illustrations depict the passage of the thoracic splanchnic nerves through the diaphragm uniformly as three nerves penetrating the crura in three separate locations along a rough superoinferior line. As this pattern does not correspond with our own sporadic observations, we performed a series of dissections to study the exact anatomy of this area. Dissections of 24 donors revealed that the most common pattern of diaphragmatic passage of these three nerves is through a single location in each crus. From this crural passageway, the three nerves then diverge to reach their targets, with the greater thoracic splanchnic nerve bending anteriorly at nearly 90 degrees to enter the posterolateral edge of the celiac ganglion. Modern anatomical illustrations should depict these most common patterns of the subdiaphragmatic portion of the thoracic splanchnic nerves and mention the great variability of their formation and structure.

Techniques and tools for digitizing analog video for use in CD-ROM-based health education programs.

This presentation is designed to familiarize medical educators with the techniques and tools for converting analog video into digital video for use in CD-ROM based multimedia programs. Recent advances in computer processing, CD-ROM storage, and digital video enable personal computers to be used for creating and presenting digital adaptations of videodisc and videotape based instructional programs. These digital multimedia programs are being used for training health care providers, for patient and family health education, and for health information kiosks. Repurposing existing analog video is a cost effective approach for creating high quality multimedia instructional programs. The presentation will cover the process of digitally capturing and manipulating video segments for playback from CD-ROM. Procedures from initial digital capture to transcoding will be discussed and illustrated. Strengths and limitations of alternative procedures will be discussed. Two CD-ROM development projects, the digital conversion of The Anatomy Project videodiscs and the creation of a patient education program on spinal cord injury, will be used as examples of techniques.

A multimedia guide to spinal cord injury: empowerment through self instruction.

The Spinal Cord Injury (SCI) Project is developing a series of instructional modules on SCI that will be distributed via CD-ROM for patient and family education. The modules are based on an instructional program and patient manual distributed by the Paralyzed Veterans of America. The program includes topics ranging from the anatomy and physiology of spinal cord injuries to legal rights established under the Americans With Disabilities Act. The SCI project expands on the instructional manual by combining digital multimedia techniques with motivational features such as games and personal guides. The user selects a personal guide from among a selection of individuals with spinal cord injuries to guide them through tutorials that include accounts of personal experiences. The guides appear in small video windows at various points throughout the tutorials and give personal insight into the topic at hand. The user can also query the other guides to hear their views on a topic. The user interface incorporates 'seamless access' features, which enable persons with a wide range of disabilities to use the program. Innovative features of these modules are the use of personal instructional guides, motivational games and activities, incorporation of alternative input or access strategies, and the use of high quality, low cost, multimedia production strategies.

Nasal capsule shape changes following septopremaxillary ligament resection in a chimpanzee animal model.

Recent human data suggest a relationship between the disruption of the septopremaxillary ligament (SPL) attachment and lack of anterior midfacial growth in cleft lip and palate (CLP) individuals. Early SPL resection in chimpanzees resulted in premaxillary growth deficits through 1200 days. Since the SPL is also continuous with the nasal bones, the present study was undertaken to investigate compensatory nasal capsule shape changes following SPL resection in a chimpanzee animal model. The study used 17 chimpanzees (Pan troglodytes): seven unoperated controls, five sham surgical controls, and five animals with early (average 144 days) SPL resection. Lateral head x-ray films and dental study models were collected quarterly and landmarks representing boundaries of the nasal capsule were identified. Mean nasal capsule polyhedrons were constructed from linear measurements at 200, 600, and 1000 days. In animals with SPL resection, the nasal capsule appeared truncated, shortened anteroposteriorly, and nasion was displaced posteriorly compared to controls by 600 days. Tensor biometric analysis of the growth/shape changes of the nasal capsule triangles revealed no significant differences across age in SPL resection animals while significant (p less than .05) age-related changes were noted in both control groups. Results showed that early SPL resection resulted in maintaining the neonatal nasal capsule morphology in the chimpanzee and suggested that such early growth mechanisms may be operating in complete CLP individuals as well. These data support the concept of early re-establishment of the SPL in primary nasolabial cleft repair to facilitate midfacial and nasal capsule growth.

Septopremaxillary ligament resection and midfacial growth in a chimpanzee animal model.

Data collected from human studies suggests a relationship between a disruption of the septopremaxillary ligament (SPL) attachment and midfacial hypoplasia in complete cleft individuals. The present study investigates the SPL-traction mechanism and midfacial growth in a chimpanzee animal model. Seventeen chimps (7 unoperated controls, 5 shams, and 5 animals with early SPL reaction) were used in the present study. Lateral head x-rays and dental study models were collected quarterly through 1200 days of age. Growth rates (slopes of the linear growth components) were statistically compared across groups. Premaxillary growth rates were significantly (p less than 0.001) reduced in SPL resected animals compared to the other groups. Maxillary growth rates were significantly reduced in both SPL and sham animals compared to unoperated controls. No significant differences were noted for midfacial height. We conclude that SPL resection produced a significant effect on anterior midfacial growth independent of surgical trauma. These data support the concept of early reestablishment of the SPL in primary nasolabial cleft repair.

The long bones of neonatal rats stressed by cold, heat, and noise exhibit increased fluctuating asymmetry.

In order to determine the effects of stress agents on the magnitude of fluctuating asymmetry in long bone measurements, data from litters of rats conceived and born in cold (10 degrees C), heat (33 degrees C), and noise (random protocol) were compared to data on control animals born at room temperature (22 degrees C). All animals were sacrificed at birth, and right and left femoral lengths were recorded. Correlation coefficients calculated for right and left femora were transformed to Hotelling's z* values which were then compared using the test of homogeneity of correlation coefficients. The magnitude of fluctuating asymmetry was found to be significantly (p less than .05) greater in the femora of animals in the three stressed groups.

Prenatal stress and increased fluctuating asymmetry in the parietal bones of neonatal rats.

Recent studies have reported increased fluctuating dental and long bone asymmetry in neonates as a function of prenatal stress. The present study was designed to assess the effects of prenatal stress on a third calcium-dependent system, membranous bone. Pregnant rats were exposed to cold, heat, or noise from conception through parturition. Bilateral parietal bone lengths were measured in the term neonates. Levels of fluctuating asymmetry were found to be significantly increased (p less than .001) in all three stressed groups compared to unstressed controls. Results support the concept of a generalized stress response, and suggestions are offered for human osteological application.

A comparison of craniofacial growth in normal and cleft palate rhesus monkeys.

In an attempt to better understand the etiology of middle ear disease in humans with cleft palate, a rhesus monkey model was developed. In this study, the model was extended to deal with the specific problem of otitis media in infants with cleft palate. Fifteen rhesus monkeys, Macaca mulatta, were utilized in the present investigation. Soft palate clefts were surgically produced in ten of the subjects, and five served as unoperated controls. Longitudinal data on middle ear status and craniofacial growth were collected until an approximate age of 2 years. Comparisons of linear regression coefficients representing size and rates of growth of craniofacial dimensions were made between operated and control group animals. No significant (p less than .05) differences were found between the groups. It is concluded that surgically produced clefts of the soft palate alter middle ear function and produce ear disease but do not change the rates of growth of the measured components of the craniofacial complex.

Traction, prenatal development, and the labioseptopremaxillary region.

Twenty-nine human fetuses ranging in age from 8 to 22 weeks were coronally sectioned for gross light microscope analysis of the labioseptopremaxillary region. In "normal" fetuses from 8 to 15 weeks, the septopremaxillary ligament was present. The horizontal and oblique fibers of the orbicularis oris muscle were poorly developed initially and increased in density with age. The anterior nasal spine and the alveolar process of the maxillae were present and in the same coronal plane. From 15 to 22 weeks, the horizontal and oblique fibers were well developed and inserted into the perichondrium of both alar and nasal cartilages. The septopremaxillary ligament was thus obliterated or more difficult to define, and the anterior nasal spine was located anterior to the alveolar process. In the cleft fetuses from 8 to 15 weeks, the nasal septum was absent or horizontally rotated. No septopremaxillary ligament or orbicularis oris fibers were noted, and the anterior nasal spine was not distinguishable. From weeks 15 to 20, the fibers of the orbicularis oris muscle were poorly differentiated, inserting asymmetrically into the perichondrium of the lateral alar cartilage on the noncleft side, the septopremaxillary ligament was absent, and the anterior nasal spine and the premaxillae were in the same coronal plane. These results suggest that the midfacial deficiencies seen in some cleft patients might have an origin in prenatal dysmorphology.

Morphology of the middle ear in the rhesus monkey (Macaca mulatta).

The purpose of this study was to provide a description of the morphology of the middle ear and related structures in the rhesus monkey, Macaca mulatta. From these descriptions, it can be seen that except for relative size differences, the middle ear system of the rhesus monkey bears close resemblance to that of man. The basic architecture is the same, thereby providing an anatomic foundation for the observed similarities in function [Cantekin et al,, 1981]. The few differences between the two systems can be summarized as follow: (1) The angle of inclination of the medial wall on the parasagittal plane is more acute in the rhesus monkey than in man. (2) The shape of the tympanic membrane in the monkey is almost circular compared to the irregular oval shape in man. (3) Differences in the shape of the ossicles as well as differences of relative measurements and angles between the parts of the ossicles were observed. (4) A major difference involves the pneumatic system and most prominently, the absence of a definite mastoid process in the monkey. However, the mastoid portion of the temporal bone is still very cellular in the majority of the specimens and communicates with the middle ear cavity through a well-defined mastoid antrum. The well-developed and extremely cellular petrous bulla in the monkey is absent in man.