Motor responses of the esophagus and lower esophageal sphincter (LES) to vestibular stimulation in man.

Pressure recordings in the esophageal body, LES and stomach were performed in 10 healthy subjects before and after caloric stimulation of the labyrinth. While esophageal and stomach responses varied or were absent, all subjects showed variations at the LES level. Duration of LES relaxation was increased and both time and amplitude of LES augmentation were significantly reduced. The physiological mechanism of labyrinthine-digestive connections and the possibility of clinical applications are discussed.

Transnasal sinusectomy with combined microscopic and endoscopic technique.

Severe, diffuse polyposis can be adequately treated through a transnasal approach which combines microscopic and endoscopic surgery. The operating microscope is used to perform ethmoidectomy, usually from the front to the back, and to open the sphenoid sinus and the antral window. The telescopes allow the sphenoid and maxillary sinuses to be cleaned under direct view control as well as enabling good drainage to be performed from the frontal sinuses. The results from 22 consecutive patients were good, with a very low rate of minor post-operative complications.

Vestibular projections to hypothalamic supraoptic and paraventricular nuclei.

The effects of electrical stimulation of the eighth nerve and caloric stimulation of the labyrinth were tested on the spontaneous or evoked electrical activity of single neurons located in the hypothalamic supraoptic (SON) and paraventricular (PVN) nuclei. It was found that these neurons responded to both kinds of stimulation. In particular, the neurons of the SON showed a predominant response pattern characterized by a sequence of excitation-inhibition, whereas the neurons of the PVN showed different patterns of response with various combinations of inhibition and excitation sequences. The latencies of these neuronal responses to the electrically induced eight nerve volleys were compatible only with a polysynaptic connection. The possible pathways involved in this vestibulo-hypothalamic relation as well as their functional role are discussed.

The vestibular cortical projection during spinal decompensation.

The removal of spinal afferents in rabbits submitted to unilateral lesion of the labyrinth and fully compensated greatly modified the field potentials as well as the single unit responses recorded from the cortical vestibular area during stimulation of the intact eighth nerve. In particular, an increase of contralateral and a decrease of ipsilateral potentials were observed. These asymmetrical responses indicate that the influence of the spinal cord in compensating the effects of unilateral lesion of the labyrinth is directed to balance not only the electrical activity of the brain-stem structures, but also that of the cerebral cortex. It appears, therefore, that spinal signals intervene not only in the compensation of vestibulospinal and vestibulo-oculomotor functions but also of cortical functions, such as that related to vestibular sensation.

[Post-operative recurrence of naso-sinus polyposis]. / Il problema delle recidive post-chirurgiche nella poliposi naso-sinusale.

Maxipolyposis, i.e. severe, diffuse nasosinusal polyposis, is generally treated with an onerous surgery. Therefore, recurrence, roughly rangling from 15% to 25%, are quite a disagreable outcome which is to be minimized. To this purpose, it may be useful to differentiate the residual from the recurrent polyposis, as is usually done in cases of cholesteatoma. Residual polyposis can be reduced by a thorough surgical resection. The authors detail their present technique, which joins microsurgery, used to perform ethmoidectomy, with endoscopic surgery, employed to manoeuvre within the sphenoid and maxillary sinus, as well as to drain the frontal sinus, i.e. to treat areas out of the direct view. Moreover, patients are warned of the need for close postoperative controls which should always be performed through telescopes in order to secure a sound inspection of the surgical cavities. Any slight, incipient recurrence should be immediately resected in the office by means of endoscopic technique. Recurrent polyposis must be treated with the drug therapies now in use, a waiting complete elucidation of the pathogenic mechanism. Association with systemic diseases, such as asthma, may contraindicate major surgery, as it increases the recurrence expectancy. Simple polypectomy often attains the same result in these cases, that is temporary ventilation of the nasal fossae.

[The problem of the mandible in surgery of tonsillar tumors: proposal of a technique]. / Il problema della mandibola nella chirurgia dei tumori tonsillari: proposta di una tecnica.

The Authors report a technique of a conservative transmandibular approach for the surgical treatment of tonsillar region malignancies. The procedure is based upon the preparation of a vascular mandibular flap through two osteotomies, which are performed, the first above the mandibular foramen and the second below the mental foramen. The main advantages of present technique are: lip-chin-splitting is avoided and, due to the preservation of mandibular vascular and nervous supply, it is possible to accomplish, without risk, postoperative radiotherapy. Moreover, if dictated by oncologic reasons, this conservative procedure may easily be transformed into a radical surgery (commando or neck-jaw operation).

Multiplanar reconstructions in the study of ethmoid anatomy.

Multiplanar and surface reconstructions are useful tools in anatomical studies. Details of ethmoid architecture which are hard to image in axial and coronal scans are well displayed by means of oblique sections. This paper addresses reformatted images of a) the nasal lateral wall; b) the middle meatus lateral wall; c) the lamina basilaris of the middle turbinate and d) the frontonasal duct.

Hematoporphyrin uptake by experimentally induced cholesteatomas in an animal model.

Photodynamic therapy is based on the production of a cytotoxic factor by porphyrins, particularly hematoporphyrin (HP), when exposed to light of a suitable wavelength and intensity. The uptake of HP is notably large in tissues with a high mitotic index. Although cholesteatomas are not malignant tumors, our working hypothesis was that their high lipid content might result in their exhibiting a remarkable affinity to HP, which is normally carried in the blood by lipoproteins. Cholesteatomas were induced in rabbits using the Tübingen procedure (closure of the auditory canal by sutures). Animals were killed 30-40 days later at intervals of 1, 3, 6, 12, and 24 h following intravenous HP administration (5 mg/kg). Specimens were divided into two portions, one for histological examination and the other for biochemical study. The latter revealed that HP accumulates in experimental cholesteatomas, with a maximum uptake after 3 h. The level then gradually decreases, although at a lower rate than in the liver, but remains considerably high even after 24 h. These results suggest that the photodynamic treatment of cholesteatomas should be feasible in our animal model, although such treatment is still speculative in man.

Anatomic variations of surgical importance in ethmoid labyrinth and sphenoid sinus. A study of radiological anatomy.

The present study was performed on axial and coronal CT scans of 100 patients, most of whom were affected by nasal polyposis. Five observers had to analyse the radiograms and answer a questionnaire including the following items: presence of a supraorbital recess; identification of anterior and posterior ethmoidal canals; dehiscences in the lamina papyracea; pneumatized middle turbinate; presence of a sphenomaxillary plate; presence of Haller's cells; presence of Onodi's cells; relationships of the optic canal; relationships of the internal carotid artery; relationships of the maxillary nerve; relationships of the vidian nerve; level difference between the ethmoid roof and nasal vault; depth of the sphenoethmoidal recess. The data obtained were compared with those drawn from anatomical studies. The fair agreement between them proves the value of CT as an alternative method for studying paranasal sinuses anatomy.

Volume receptors in guinea pig labyrinth: relevance with respect to ADH and Na control.

We tested the hypothesis that changes in extracellular fluid volume are reflected by pressure changes within structures of the inner ear and that through neural pathways, a control mechanism exerts an influence on antidiuretic hormone (ADH) release and Na excretion. The study was performed on 35 guinea pigs. In protocol 1, 13 animals were studied before and after decompression of the inner ear by bilateral fluid withdrawal in an experimental setting of sustained isotonic expansion that kept the osmoreceptor partially activated and the intrathoracic volume receptors suppressed. A group of six sham-operated animals served as control. In protocol 2, nine animals were studied before and after a unilateral rise in their inner ear pressure during slightly hypertonic low-rate infusions that kept the osmoreceptor and thoracic volume receptors stimulated. A group of seven sham-operated guinea pigs served as controls. Decompression of the inner ear was attended by a rise in plasma ADH from 11.9 +/- 2.4 to 29.1 +/- 6.9 pg/ml, in urine osmolality (Uosmol) from 470 +/- 48 to 712 +/- 46 mosmol/kg (P less than 0.001), and a fall in urine flow rate (V) from 184 +/- 47 to 71 +/- 11 microliters/min (P less than 0.01), whereas plasma Na (PNa) and osmolality (Posmol) did not change. During inner ear hypertension, plasma ADH fell from 25.6 +/- 3.9 to 18.4 +/- 3.1, Uosmol from 829 +/- 58 to 627 +/- 43 (P less than 0.001), and V rose from 51 +/- 11 to 130 +/- 23 (P less than 0.001), whereas glomerular filtration rate, PNa, and Posmol did not change.(ABSTRACT TRUNCATED AT 250 WORDS)