Because of the dense innervation of arteries and subendothelial venous muscular bolsters we conclude that the swelling mechanism of human nasal mucosa is mainly regulated by these structures. A dual (endothelial and neuronal) control exists in arterioles whereas the control in the subendothelial muscular swellings of the cushion veins appears to be mainly neuronal. The swelling of the nasal mucosa is achieved by an simultaneous relaxation of all smooth muscle cells, which leads to dilatation of arteries as well as venous sinuses. The drainage of the vascular bed is reduced by the venous muscular bolsters protruding into the lumen of the venous sinuses. Vice versa, a contraction of all smooth muscle cells leads to a contraction of the arteries and, consecutively, to a reduction of blood supply. Simultaneously the muscular bolsters are torn out of the lumen of venous sinusoids allowing blood drainage to be increased: nasal concha decongests.

After implantation of resorbable materials for internal fixation, foreign body reactions are described in 0-47% of cases. Copolymers of poly-l-lactic acid (PLLA) and polyglycolic acid (PGA) seem to offer better biocompatibility than other materials. One of our patients had a midfacial fracture, which we fixed using a resorbable system based on PLLA-PGA (82%-18%); a foreign body reaction developed after 22 months. When resorbable materials are used it is essential to be aware specifically of the risk of foreign body reactions, especially when the facial area is involved. This risk must be discussed with the patient in some detail during the preoperative period.

During the period 1992-1998,we diagnosed orbital tumors in 23 cases at the MLU Halle-Wittenberg. In the intraconal compartment we mostly saw cavernous hemangiomas and neurogenic tumors. Lymphomas and a primary meningioma were located in the extraconal space. Beneath the periosteum, bony processes, tumors of the sinuses, dermoid-and epidermoid-cysts normally occur, but we only observed metastases and hematomas. Furthermore,tumors of the lacrimal gland and inflammatory lesions were diagnosed. Orbital tumors are uncommon lesions, whose location in the orbit gives an important hint to differential diagnosis, because a high percentage of various pathologies is located in special compartments of the orbit. According to our results,the MRI-scan is usually sufficient for differentiation and for preoperative planning in order to reduce the X-ray dose of the lens. CT-scans with contrast are sometimes necessary for examining bone destroying processes and for planning the surgical approach to removing the tumor. X-rays of the skull widely lost their importance in the exact diagnostic of orbital tumors. B-scan ultrasonic imaging is reserved for screening and follow-up examination. Despite the use of MRI and CT scanning, the histological examination remains necessary.

Seromucous glands are among the main components of human nasal mucosa. To control the different physiological functions of these glands, a dense nerval network is necessary. The aim of this study was to demonstrate the general innervation of the seromucous glands in nasal mucosa. Tissue samples of inferior human turbinates were fixed and embedded in paraffin wax or frozen. Serial sections were performed and incubated with antibodies either to neuron-specific enolase (NSE) or S-100 protein. The ABC method was employed to demonstrate the immunacomplexes. The sections were counterstained with haemotoxylin. Either NSE and S-100 protein-immunoreactive nerve fibres were found around the acini, ducts and in the connective tissue of the glands. Furthermore, a dense network of fine nerve fibres was detected in the submucosal region. The localisation of neurons in nasal glands confirms the direct nerval control of the diverse glandular functions. Additionally, the sensitive subepithelial network of fine nerve fibres might be involved in the regulation of glandular secretion.

In the edematous nasal mucosa an infiltration with different inflammatory cells was found. Using electron microscopical techniques nerve structures near the submucosal glands could be demonstrated. Immunoreactions to the neuropeptides CGRP and SP were detected in the periglandular nerves and in neuroglandular synapses. These findings demonstrate the direct nerve control of glandular functions in allergic rhinitis. CGRP is generally known to have a vasodilatatory effect and to stimulate the secretion of nasal seromucous glands. In addition, SP as a short-acting vasodilatator may induce vascular permeability and glandular secretion. These immunoelectron microscopical findings further elucidate pathomorphological mechanisms in allergic rhinitis.