Graeme Clark Collection
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ItemA review of the structural support of the nose( 1969)An understanding of the structural support of the nose is important in the management of septal and nasal deformities and of fractures of the nose. Therefore, it is considered pertinent to trace the development of our knowledge of these supporting mechanisms.
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ItemA technique for a wide approach to the medulla and bullae of the cat( 1969)Ready access to the bullae and auditory pathways in the medulla can only be achieved by the ventral approach. A wider exposure is required than for approaches to other structures in the medulla, such as the trigeminal nuclei and pyramidal tracts. In our neurophysiological experiments it was frequently necessary to use three electrodes to stimulate and record from the auditory pathways in the medulla. To accommodate these electrodes in the medulla and operative field at the one time, wider access was needed than provided by the standard approach described by Boudrequ and Rohwer (1964). In their approach the tissues were dissected lateral to the larynx so that it could be retracted to one side, but we were able to obtain a wider approach by mobilization of the larynx and pharynx, division of their supporting structures, ligation of one common carotid artery, and incision of the larynx and pharynx. The anatomical terminology used in the description of this method is from Reighard and Jennings, 1966.
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ItemResponse patterns in the superior olivary complex of the cat [Abstract]( 1969)Poststimulus-time histograms were recorded from 200 cells in the superior olivary complex of the cat in response to tone pulses. The sites of the phase reversal of field potentials enabled the cells to be placed in one of the three main subdivisions of this complex and their firing patterns to be compared.
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ItemPoststimulus-time response patterns in the nuclei of the cat superior olivary complex( 1969)In this study, the poststimulus-time response patterns from 200 cells in the superior olivary complex have been analyzed. There were 82 from the trapezoid body, 73 from the medial superior olive and 45 from the S-shaped lateral superior olive. On-and off-responses were most commonly observed in the medial superior olive. They were frequency and rise-time-dependent. and binaural stimulation produced different degrees of inhibition for each response. A variety of inhibitory patterns were seen, and these were classified into five categories called burst, onset, repetitive, bilateral, and background inhibition. With the exception of burst inhibition, they were all found most commonly in the medial superior olive, and a neuronal model was constructed to explain these patterns and the binaural interaction that occurred with on-and off responses. Background activity was greater in the trapezoid body and practically absent from the recordings in the S-shaped lateral superior olive. No differences were observed ill the response patterns to different frequencies, intensities, or stimulus durations in the three main subdivisions of the superior olivary complex.
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ItemVesicle shape versus type of synapse in the nerve endings of the cat medial superior olive( 1969)Synapses have been classified into type I and type II synapses by Gray, and in a review by Eccles it was suggested that the type I synapse could be excitatory, and the type II inhibitory in function. Another possible relation between morphology and function has been demonstrated by Uchizono and Bodian. They have shown that some boutons contain spheroidal (S-type) and other flat (F-type) vesicles, and that S-type boutons make synaptic contact at sites known to receive an excitatory input. and F-type boutons at sites receiving an inhibitory input.
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ItemThe ultrastructure of nerve endings in the medial superior olive of the cat( 1969)The medial superior olive (MSO) is an important nucleus for the coding of sound localization and this requires a binaural interplay between excitation and inhibition. A variety of inhibitory effects have been demonstrated in the MS02 and post-stimulus time response patterns show that they can be quite complex. The present study has been undertaken to examine the nerve endings in the MSO to see whether a morphological basis for inhibition and excitation can be found, as this has been demonstrated in other areas of the brain.
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ItemSpecially processed heterogenous bone and cartilage transplants in nasal surgery(Cambridge University Press, 1969)In nasal surgery, cartilage or bone transplants are required for support or correction of cosmetic deformities. When autogenous material is readily available, it should be used in preference to homogenous or heterogenous material. Sometimes this means, however, an iliac bone or rib cartilage graft. These procedures have a certain morbidity and the grafts are not always readily accepted by the patient. For this reason, there is a place for heterografts, especially when their antigenicity is reduced. Embryo calf bone and cartilage can be specially treated by lyophilisation and surface active agents to reduce its antigenicity (Dingwall and Millonig, 1964) and this material has been used in the present clinical study. This is a publisher’s version of an article published in The Journal of Laryngology & Otology © 1969 Cambridge University Press. www.cambridge.org/
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ItemResponses of cells in the superior olivary complex of the cat to electrical stimulation of the auditory nerve( 1969)This study has shown that electrical stimulation of the auditory nerve in the cat at a certain rate will not reproduce the same firing patterns in the cells of the superior olivary complex as a tone of the same frequency. This occurred because the electrical stimulus probably produced synchronous firing of all the auditory nerve fibers, and the inhibitory mechanisms of the cochlear nucleus prevented activation of the auditory cells for all stimulus rates greater than 200/sec. On the other hand, a few cells were recorded in the medial superior olive which gave on-and off-responses to a tone and this firing pattern was reproduced with an electrical stimulus. Although electrical stimulation could not cause sustained excitation of cells, inhibition of spontaneous activity occurred for the duration of the stimulus in a number of cases. This was considered to be due to the effect of efferent stimulation of the olivocochlear bundle on spontaneous activity arising from the cochlea. Bipolar electrical stimulation of the cochlea was also carried out and this excited some cells in the superior olivary complex with characteristic frequencies in the middle to high frequency range. It was not possible to be certain, however, whether this was due to electromechanical stimulation or direct excitation of auditory nerve endings.
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ItemNasal splints and nose guards( 1969)Nasal fractures are common, and although their surgical treatment is standardized, there is disagreement about their splintage and postoperative management. A variety of nasal splints are at present in use. Small splints of aluminium or dental impression compound, which can be moulded to the nose, are available. More commonly a plaster splint is applied, and this is fixed in place with adhesive strapping or tapes around the head. The plaster may be cut so that it has a broad area for attachment to the forehead or broad flanges for resting on the maxillae to provide further support. In the latter case, the plaster is usually fixed in place by connecting it to tapes which are tied behind the head. In no case should a splint be applied in the hope that it can exert pressure on and compensate for an incompletely reduced fracture. Satisfactory postoperative results will be obtained only if reduction is complete at the time of the operation. Therefore the main function of splints for nasal fractures without loss of support is to prevent further injuries displacing the bones during healing.
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ItemHearing due to electrical stimulation of the auditory system( 1969)One of the major problems facing otologists today is the treatment of perceptive deafness. The results of treating patients with deafness due to middle-ear disease are now good, but this is not the case when there is damage to the inner ear or central auditory pathways. A hearing aid will assist a great many people, but there are a number of patients with very severe or total deafness who cannot be helped in this way. Consequently, a different approach to the problem must be made, and for this reason, electrical stimulation of the cochlea or auditory pathways to reproduce the natural stimulus may provide a solution.