Caudal Septum Research Articles

Correction of the crooked nose.

Correcting the crooked nose remains one of the most challenging problems in rhinoplasty. When faced with a twisted nose, rhinoplasty surgeons tend to be divided into those who perform an anatomic reconstruction and those who prefer camouflage techniques. Regardless of the approach used, the revision rate remains fairly high. An anatomic correction of the twisted nose through an open approach was performed. The septum was freed from the extrinsic forces of the deformed nasal bones and upper and lower lateral cartilages. The residual true septal injury was then evaluated. The septal deformity was addressed through quadrangular cartilage resection, repositioning of the caudal septum in the anatomic midline, and correction of the dorsal septal deformity with horizontal control sutures. The skeletal support was then reconstructed with the use of a spreader-extension graft on the concave side and a batten graft on the opposite side. The nasal tip was set relative to the dorsum by fixation to the extension grafts. Residual lateral crus deformities were corrected by a combination of lateral crural spanning sutures or alar spreader grafts. With this approach, straightening the crooked nose without compromising skeletal support or nasal aesthetics was successful.

Identification of alpha1B adrenergic receptor protein in gonadotropin releasing hormone neurones of the female rat.

Noradrenaline is an important neurotransmitter which regulates GnRH release from the median eminence in the female rat during both basal GnRH secretion and the preovulatory or steroid hormone-induced GnRH-mediated LH surge. However, it is not clear at which sites in the brain this predominantly stimulatory influence is exerted nor is it known which adrenergic receptor subtype(s) mediate(s) the effects of noradrenaline. In order to determine if the GnRH neurones in the septum-diagonal band-preoptic area and/or their axon terminals in the median eminence are direct targets for noradrenaline, immunohistochemical triple-labelling studies were conducted to localize simultaneously GnRH peptide, dopamine-beta-hydroxylase and alpha1B adrenergic receptor protein. The results show that about 80% of all GnRH neurones examined contained patches of immunoreactive alpha1B adrenergic receptor protein at or near the plasma membrane and that some of these alpha1B adrenergic receptors were adjacent to dopamine-beta-hydroxylase containing axons. The GnRH neurones which did not contain alpha1B adrenergic receptors were preferentially located in the rostral portion of the septum and diagonal band while all GnRH neurones in the caudal septum, diagonal band and in the preoptic area expressed alpha1B adrenergic receptors. In the median eminence, a few alpha1B adrenergic receptor patches were seen in the external layer and these receptors were only rarely observed to be associated with GnRH containing axon terminals. The results suggest that the effects of noradrenaline on GnRH release are, at least in part, mediated by the activation of alpha1B adrenergic receptors which are located on most GnRH perikarya while the median eminence is not a likely site at which GnRH release is regulated by alpha1B adrenergic receptors.

Feeding behavior of the poecilostomatoid copepods Oncaea spp. on chaetognaths

Feeding behaviors of the poecilostomatoid copepods Oncaea venusta, O. mediterranea and O. conifera were examined in the coastal area of Cheju Island, south of the Korean Peninsula, from April 1993 to November 1995. Late copepodid stages (CV, adult female and male) showed a high frequency of association with larger zooplankton such as Sagitta spp. (Chaetognatha), Oikopleura spp. (Appendicularia), and Salpa spp. (Thaliacea) in a coastal upwelling zone and around the small Munsum Island. Attack behaviors on Sagitta observed under the microscope and in the field showed that Oncaea approached Sagitta using their swimming legs, and then crawled chiefly to the neck regions and caudal septum (around the tail) of Sagitta spp. using their second antennae. They pierced the body of Sagitta with their sharp maxillipeds, and moved their maxillae and mandibles repeatedly. Midgut contents of Oncaea spp. consisted mainly of unidentified fine particles, and the greater part of the gut was empty. Their mouthpart structure is remarkably different from other pelagic copepods. Such differences of the mouthpart structures and the feeding habits in the genus Oncaea around Cheju Island are discussed in terms of feeding behavior and ecology in this coastal upwelling area.

Septoplasty: A Comparison of Septocolumellar and High Septal Hemitransfixion Approaches to the Nasal Septum

<i>Objectives:</i> To compare the classical septocolumellar approach with the high septal hemitransf&#205;xion incision for deformities of the nasal septum. <i>Patients and Methods:</i> A prospective randomised controlled trial of 56 patients undergoing primary septoplasty over a 6-month period was carried out. Pre-operatively, symptoms and signs were assessed. A high septal approach was used in 32 patients and a septocolumellar approach in 24 patients. Postoperative evaluation at 6 months included alteration of symptoms, clinical appearance of the septum and complications. <i>Results:</i> Overall subjective symptoms improved in 75% of the septocolumellar group and 87.5% of the high septal group (p &#62; 0.2). The septum was noted to be straight postoperatively in 66.6% of the septocolumellar group and 93.8% of the high septal group (p = 0.01). There was no significant difference in the pattern of symptom scores between the two groups (p = 0.6503). There was a statistically significant difference in the alteration of sign scores between the two groups (p = 0.0162). Assessment of complications showed temporary numbness over the columella and tip in 8 cases (33.3%) in the septocolumellar group in contrast with no cases in the high septal group (p &#60; 0.001) and 5 cases of recurrent dislocation of the caudal septum and 2 cases of columellar retraction in the septocolumellar group compared to no similar complications in the high septal group (p &#60; 0.01). <i>Conclusions:</i> The high septal hemitransfixion incisions provides more improved, although non-significant, results for alteration of symptoms but a significant improvement on objective assessment and a lower incidence of complications, particularly postoperative numbness, than the septocolumellar incision.

A Septum-Derived Chemorepulsive Factor for Migrating Olfactory Interneuron Precursors

During mammalian brain development, immature neurons often migrate considerable distances. A dramatic example is the rostral migration of olfactory interneuron precursors from near the septum to the olfactory bulb via a subventricular pathway. Heterotopic transplantations establish that this migration is unidirectional and that guidance cues operate over a considerable distance. The guidance cues for this translocation have not been identified, and the present studies provide evidence that a diffusible chemorepulsive factor, secreted by caudal septum but not by other tissue regions surrounding the pathway, may be involved. This activity is functionally distinct from that produced by factors that influence vertebrate axon outgrowth, such as netrin-1, netrin-2, and collapsin-1/semaphorin-III. The presence of this activity in the floor plate/ventral spinal cord as well as the septum suggests that it may influence other types of cell migration.

Dynamics of Rhinoplasty

Nasal dynamics were studied on 87 patients undergoing rhinoplasty of one zone or two distant nasal zones. Statistical analysis of the result revealed that reduction of the nasion area, besides setting the soft tissue back, gave the appearance of increased intercanthal distance and lengthened the nose. Reduction of the nasal bridge resulted in a wider appearance on front view and a cephalically rotated tip on profile. Augmentation of the bridge affected the nose reversely. Tip cephalad rotation was achieved by resecting one of the three areas: the cephalad portion of the lower lateral cartilages (affecting the rims more), the caudal septum (affecting the central portion more), and the caudal portion of the medial crura of the lower lateral cartilages (affecting the central portion only). Resection of the alar base not only narrowed the nostrils but also moved the alar rim caudally. Furthermore, it reduced tip projection when a large alar base reduction was done. Reduction of the nasal spine increased the upper lip length on profile and reduced tip projection when a large reduction took place. Significant reduction in caudal nose projection resulted in widening of the alar base.

Nasal Tip Projection: Quantitative Changes Following Rhinoplasty

Fifty-one patients were enrolled in a study and underwent primary rhinoplasty. Serial nasal tip projection measurements were made preoperatively, intraoperatively, and 6 months postoperatively. Actual changes in measured nasal tip projection were evaluated with respect to preoperative goals and specific procedures used to accomplish these goals in the nasal tip. Several useful observations are made from these data: (1) The most important components of nasal tip projection in the postsurgical nasal tip are the medial crura, their attachment to the caudal septum, and the presence of additional cartilaginous grafts placed between the medial crura or beneath the crural feet. (2) Actual nasal tip projection will decrease postoperatively, unless measures to increase the length and strength of the medial crural segment are taken (ie, McCollough-modified Goldman tip procedure, cartilage struts, plumping grafts, etc), regardless of the preoperative goal. (3) The double-dome unit procedure is effective in narrowing the wide or bulbous lobule but alone does not permanently increase nasal tip projection. (4) Conservative tip procedures, such as a complete strip, result in decreased nasal tip projection and should therefore be used in patients in whom retrodisplacement of the nasal tip is the intended result.

Aberrant phosphorylation of neurofilaments accompanies transmitter-related changes in rat septal neurons following transection of the fimbria-fornix

Lesions of the fimbria-fornix (FF) have been reported to cause retrograde changes in neurons of the medial septal nucleus (MSN). To analyze the nature and time course of these events, we investigated changes in cytoskeletal elements (phosphorylated and nonphosphorylated neurofilament (NF) proteins) and transmitter-related enzymes (choline acetyltransferase (ChAT) in MSN neurons following FF transection. During the first week postlesion, ChAT immunoreactivity and size of many perikarya were reduced. Irregular, swollen cholinergic fibers appeared first at postlesion day 2 in caudal septum and soon spread rostrally, reaching rostral septum by day 7. A few perikarya developed abnormal accumulations of phosphorylated NFs. At postlesion days 7–10, many neurons did not stain for ChAT. Phosphorylated NFs were present in many perikarya. At this time, cell loss was apparent in Nissl-stained material. Cholinergic cell loss continued through postlesion week 6–8 but at a much slower rate than during the first week. Phosphorylated NF accumulations in MSN perikarya persisted until postlesion week 6, disappearing thereafter. Double-immunostaining procedures showed that MSN neurons expressed both ChAT and phosphorylated NF immunoreactivity at postlesion day 3; however, at days 7 and 14, cells that accumulated phosphorylated NFs did not stain for ChAT. The results of this study indicate that FF transection leads to perikaryal shrinkage with loss of ChAT immunoreactivity, perikaryal phosphorylation of NFs, cholinergic fiber abnormalities, and cell loss. Recent evidence suggests that reduction of transmitter markers and aberrant phosphorylation of NFs may be involved in the pathogenesis of several neurodegenerative disorders, including Alzheimer's disease. Therefore, FF transection provides a useful animal model for further investigations of complex disorders of the central nervous system that involve degeneration of transmitter-specific pathways.

The Expert Teaching System

We have developed software that employs interactive computer graphics to simulate the surgical experience of rhinoplasty by allowing the surgeon to experiment within a model of nasal behavior. For any of three preoperative noses, the surgeon can choose and see the effects of dorsal resection, modification of nasal spine or caudal septum, alar cartilage resection, osteotomy, alar wedge resection, and a variety of nasal grafts. The available choices and views total nearly 3000 images, or approximately 200 different surgical solutions. The surgeon can get textual analysis at any time or see accelerated healing to the projected nasal appearance at 1 year. We believe that the ability to experiment without risk, to safely learn the biological laws governing nasal behavior, should augment the development of surgical judgement in rhinoplasty.

Auricular Sandwich Graft for Caudal Septal Augmentation

Retraction of columella and collapse of nasal tip may be a primary phenomenon or secondary to poor results of rhinoplasty. This may be due to excessive resection of dorsocaudal septum or inappropriate removal of the nasal spine. Reconstruction of the columella is a difficult surgical procedure and many techniques have been described. This report describes a technique of interposition of a composite skin-conchal cartilage graft between the caudal septum and columella. The graft will restore the projection of the nasal tip and correct a retracted columella by increasing its base. The newly positioned columella forms an aesthetically acceptable obtuse angle with the lip and is 2–3 mm lower than the alar rims. The cartilage from the concha of the ear is an excellent grafting material for nasal reconstruction. It has been used for augmentation of the nasal dorsum, tip grafting, and correction of vestibular atresia. The graft is harvested utilizing a technique that allows for minimal postoperative auricular deformity at the donor site. Aesthetic results have been satisfactory, with very low morbidity following this method.

Stable isotopic variation in pteropods and atlantids from North Pacific sediment traps

To determine their usefulness in paleoenvironmental studies and to better understand isotopic equilibrium in biogenic aragonite, carbon and oxygen isotopic analyses were performed on six species of pteropod and two species of atlantid collected with free drifting sediment traps from the North Pacific Ocean. Where the depth habitat of a species is constrained enough to permit estimation of the ambient temperature and water δ 18O, the isotopic compositions of the shells are close to aragonite-water 18O equilibrium with the ambient water. None of the fauna are in 13C equilibrium with the dissolved bicarbonate. Assuming aragonite-water equilibrium fractionation, the δ 18O values of the shells provide reasonable average depths of shell growth. The distribution is as follows: (1) “shallow-water” species (< 75 m) — Diacria quadridentata, Cuvierina columnella (32°N), and Atlanta (100 m trap); (2) “intermediate-water” species (75–125 m) — Diacria trispinosa, Styliola subula, Limacina bulimoides, C. columnella (26°N), Peraclis reticulata, and Atlanta (400 m trap); and (3) “deep-water” species (> 125 m) — L. bulimoides (small). The 18O variation within specimens of C. columnella, a large, easily sectioned species, is complex with no clear record of seasonality. However, some minor seasonal effects are observed. The δ 13 C values within specimens consistently show a 1–2‰ decrease from the caudal septum to the aperture, perhaps reflecting increased incorporation of metabolic CO 2 with age.

The subicular cortex of the cat: An anatomical and electrophysiological study

The anatomic organization of the hippocampal formation in the cat was studied by means of (a) horseradish peroxidase histochemistry, (b) [ 3H]leucine radioautography, and (c) electrophysiological identification of antidromically activated single units. The data indicate that the CA 1 field, prosubiculum, and adjacent subiculum are the source of origin of fibers terminating in the caudal septum. The subiculum and adjacent presubiculum are the only sources of hippocampal efferent fibers which project to the medial mammillary nucleus. The cells of the presubiculum and retrosplenial cortex give rise to the axons which project to the anterior thalamus. Efferent fibers project through the fornix and are topographically distributed to the mammillary bodies and septal area. Specifically, axons arising near the septal pole of the hippocampal formation project to the dorsal aspect of the medial mammillary nucleus or the dorsomedial part the lateral septal nucleus. Axons arising from cells situated progressively more proximal to the temporal pole of the hippocampal formation project to progressively more ventral levels of the medial mammillary nucleus or more lateral parts of the lateral septal nucleus. It was also noted that subicular fibers have slow conduction velocities and that evidence of possible axonal branching of fornix fibers was not obtained.

Evidence of an incerto-hypothalamic dopamine neurone system in the rat

With the recently introduced glyoxylic acid histochemical fluorescence method, a previously unknown catecholamine-containing fibre system has been revealed in the zona incerta, hypothalamus and the caudal septum. These fibres, designated the incerto-hypothalamic system, have a characteristic, very delicate, finely varicose appearance, and they have a weak fluorescence, indicating an unusually low intraneuronal amine content. On the basis of their distribution a caudal and a rostral part can be discriminated: the caudal part extends from the area of the dopamine-containing cell bodies in the caudal thalamus, the posterior hypothalamic area and the medial zona incerta (the A11 and A13 cell groups) into the dorsal part of the dorsomedial nucleus and the dorsal and anterior hypothalamic areas; the rostral part extends from the area of the rostral periventricular dopaminergic cell system (the A14 cell group) into the medial preoptic area and the periventricular and suprachiasmatic preoptic nuclei. The system probably extends also into the most caudal portion of the lateral septal nucleus. From a series of lesions and in vitro uptake studies, evidence has been obtained that the incerto-hypothalamic fibres are the projections of short, intradiencephalic dopaminergic neurones whose cell bodies are located in the A11, A13 and A14 cell groups. The projection areas of these neurones signify an involvement of the system in the control of secretion of pituitary hormones.

Studies on the support of the nasal tip

Anatomical studies on the nasal tip indicate four major areas of tip support: (1) the fibrous connection between upper and lower lateral cartilages; (2) the sesamoid complex extending the support of the lateral crus to the pyriform opening; (3) the ligamentous sling spanning between the paired domes of the lower lateral cartilages; and (4) the attachment of the feet of the medial crura to the posterior caudal septum. Routine rhinoplasty procedures compromise tip support predisposing to postoperative tip sagging (Pollybeak); however, tip rhinoplasty procedures can be modified to maintain tip support and projection by: high transfixion through the caudal cartilaginous septum confirming septal shortening to the anterior caudal septum, embricating the membranous septum over the anterior caudal septum, utilizing a cartilaginous strut, between and below the medial crura, or reestablishing the medial cruraposterior caudal septum anchorage.

Studies on the support of the nasal tip.

Anatomical studies on the nasal tip indicate four major areas of tip support: (1) the fibrous connection between upper and lower lateral cartilages; (2) the sesamoid complex extending the support of the lateral crus to the pyriform opening; (3) the ligamentous sling spanning between the paired domes of the lower lateral cartilages; and (4) the attachment of the feet of the medial crura to the posterior caudal septum. Routine rhinoplasty procedures compromise tip support predisposing to postoperative tip sagging (Pollybeak); however, tip rhinoplasty procedures can be modified to maintain tip support and projection by: high transfixion through the caudal cartilaginous septum confirming septal shortening to the anterior caudal septum, embricating the membranous septum over the anterior caudal septum, utilizing a cartilaginous strut, between and below the medial crura, or reestablishing the medial cruraposterior caudal septum anchorage.

Correction of deviated nose. Interim septal surgery vs combined approach.

Management of commonly encountered septal deviations is related to the timed performance of rhinoplasty for the correction of the deviated nose. Deviations of the septum, limited to the vomerine perpendicular plate in the area of the floor of the nose, can generally be corrected simultaneously with a rhinoplasty, as well as deviations of the caudal septum. However, if shortening of the septum is to be avoided, and if the supportive capabilities of the caudal septum have been compromised, postponement of the rhinoplasty is recommended. Deviations of the ventral-caudal septurn can occasionally be performed simultaneously with a rhinoplasty especially in patients with long noses and prominent bony cartilaginous humps. Frequently, it is advantageous to perform the septal surgery as a preliminary procedure followed, after an interval of time, by a rhinoplasty. In patients with extensive deviations involving the entire septum, simultaneous rhinoplasty is not recommended.