Virtual endoscopy of the middle and inner ear with spiral computed tomography.

OBJECTIVE: To evaluate the inner anatomy of the auditory apparatus by means of virtual endoscopy of spiral computed tomography (CT) data sets. BACKGROUND: Virtual endoscopy permits simulation of the fiberoptic endoscopy perspective by processing CT or magnetic resonance images. METHODS: Seven formalin-fixed specimens of human mastoid were scanned with spiral CT with the following protocol: beam collimation 1 mm, pitch ratio 1, reconstruction spacing 0.2 to 0.5 mm, field of view 90 mm. For the generation of endoscopic views of the auditory spaces, the axial images were processed with Navigator software 2.0 running on UltraSparc I workstation. RESULTS: Virtual endoscopy allowed the demonstration of the external auditory canal, the head and handle of the malleus, the stapes and incudostapedial articulation, the corpus, the long process of the incus with its lenticular process and the short limb, the malleoincudal articulation, the rounded promontory, the round and oval windows, and Prussak's space. From inside the basal turn of the cochlea, virtual endoscopy showed the orifices of the fenestrae cochlea and vestibuli, the origin of the lateral and the anterior semicircular canals, and the basal turn of cochlea. The optimal perspectives that allowed demonstration of the anatomical details of the middle and inner ear are described. CONCLUSION: Virtual endoscopy allows the generation of inner views of the auditory spaces. This new method of image processing can be proposed as an integrative tool of spiral CT imaging.

An unusual neck mass: the Warthin tumor.

The cystoadenolymphoma or Warthin's tumor is a benign lesion of the salivary glands and principally of the parotid gland. We report a case of a 62 year old white male seen at our Institute for evaluation of an asymptomatic right neck mass located 2 cm below the mandible at the anterior margin of the sternocleidomastoid muscle. The echography showed a lymphoid structure simulating a lymphoproliferative process. Histologic examination of the surgical specimen revealed a Warthin's tumor. We discuss the importance of considering Warthin's tumor in the differential diagnosis of an isolated neck mass, and report our experience over a ten year period in the surgical management of neck masses. Additionally, the literature concerning extraparotid Warthin's tumors is reviewed.

[Progressive sensorineural hearing loss from infectious agents]. / Ipoacusie neurosensoriali progressive da agenti infettivi.

The progressive sensorineural hearing loss due to infectious causes can involve different etiological agents like bacteria, viruses, protozoons or mycetes. These infectious agents can act in various ways: directly through a labyrinthitis that may destroy the neuroepithelium; through an ischaemic process secondary to a septic embolus; or through a thrombus. In some cases the damage can occur in a meningitis context, because of the passage of the germ in the inner through the nerves, the vases or the labyrinthine liquids. Bacterial meningitis is one of the causes of progressive sensorinueral hearing loss. Among bacteria, the Mycobacterium Tuberculosis has nowadays acquired a remarkable importance which is also due to its considerable diffusion, despite modern therapy, and to its association with HIV infection. Bacteria can also cause a labyrinthitis acting directly on the inner ear: among these, Treponemas Pallidum, a spirochaete which causes syphilis and Borrelia Burgdorferi, a spirochaete that causes Lyme Disease, must be mentioned. The viruses that are certainly involved in the etiology of progressive sensorineural hearing loss are Cytomegalovirus and Rubella virus. The virus usually causes a labyrinthitis after the viraemia, wich may be due to the passage of the virus from the blood to the endolymph, through the stria vascularis with the consequent infection of the sensorial cells of the organ of Corti. Less frequently the viral damage to the inner ear can occur after a vasculitis, a meningitis or an alteration of the cell-mediated immunity. Progressive sensorineural hearing loss can also occur because of some congenital viral infections such as those caused by Cytomegalovirus and Rubella virus. More recently even the Human Parvovirus B19 seems to have been involved. This virus seems to act through autoimmune and/or immunologic processes, like that causing sudden hearing loss in Lassa fever. Another viral infection which can nowadays more frequently be considered among the cause of progressive hearing loss is HIV. In the HIV infection the neurological toxic lesions due to the administered ototoxic drugs are added up to the damages caused by the opportunistic infectious agents (virus, bacterium, protozoon mycete). However, in these patients HIV itself could be the cause of the auditory and vestibular lesions. More rarely, a progressive hearing loss may be due to the action of a protozoon or mycete only.

[HIV infection and nosocomial risk: experience at the ORL Clinic of Pisa]. / L'infezione da HIV e il rischio nosocomiale: esperienza della clinica ORL di Pisa.

The risk of nosocomial risk of HIV infection and the problem of preventative measures to adopt has been modifying how workers in the health field deal with patients. In fact, the increased spreading of HIV infections within our population has led to the establishment of a national protocol of preventative measures by which no patient can be considered "safe". Consequently, the likelihood that contact with any patient can lead to infection causes the health care worker to look upon the patient as a potentially dangerous enemy, thus leading to a decline in the quality of health care. On the other had, although the risk of a health care worker being infected by HIV during routine work is low, preventative measures must be taken both during examination and during surgery. Unanimous agreement exists in regard to what measures are to be taken to prevent cutaneous and mucosa exposure of workers whenever the risk of accidentally coming into contact with the blood and/or other biological fluids exists. On the other hand, the use of an anti-HIV screening for all patients in order to distinguish between infected and non infected subjects is still subject to debate. Some feel such screening is unacceptable because it would deny sero-positive patients adequate care and could give rise to both false positives and false negatives while others propose routine screening feeling it to be helpful both to those who are sero-positive and to health care workers.(ABSTRACT TRUNCATED AT 250 WORDS)