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S Gherini

Publications and source records attributed to S Gherini.

15 recordsLinked to original sources

Impedance transfer: acoustic impedance of the annular ligament and stapedial tendon reconstruction in otosclerosis surgery.

The resistance rebuilt around the lower tip of the piston must be the same as that created by the annular ligament of the stapes footplate. Otherwise, the threshold at which an acoustic or barotrauma is able to damage the membranes and hair cells of the inner ear will be lowered. The elasticity reestablished around the lower tip of the piston plays a part in the quality and quantity of hearing for the low frequencies up to 3 kHz. To protect the ear against acoustic traumas, an attempt to rebuild the stapedial reflex is proposed.

Acoustic Impedance Tests

Delayed wound healing and nutritional deficiencies after total hip arthroplasty.

Ninety-two patients (103 hips) treated with total hip arthroplasty (THA) were assessed before and after operation to determine nutritional status and any correlation with delayed wound healing. Parameters indicative of nutritional status (serum albumin and serum transferrin) were assessed, along with immunologic and anthropometric parameters. Delayed wound healing complicated 34 of the 103 (33%) THAs. The preoperative serum transferrin levels were significantly lower for patients who subsequently developed wound-healing complications. Patients treated with single-stage, bilateral procedures had substantially lower postoperative serum transferrin and serum albumin levels and significantly higher incidences of delayed wound healing (64%) than patients who had single joint procedures (25%). Only preoperative serum transferrin levels showed significant value in predicting which patients would have delayed wound healing. None of the other serologic variables, including serum albumin and total lymphocyte count, proved to be a predictor of delayed wound healing. The preoperative assessment of three variables--serum transferrin value, bilateral procedure, and patient age--resulted in the correct prediction of wound healing outcome in 79% of the patients. This preoperative information, in combination with postoperative monitoring of serum transferrin and albumin levels, should alert the physician to the approach of a malnourished state. The malnourishment is attributable to heightened demands on the body's basal energy requirements after major orthopaedic surgery and can increase morbidity and prolong the hospital stay.

Age Factors

Surgical treatment of stapes fixation by fiberoptic argon laser stapedotomy with reconstruction of the annular ligament.

The goal of surgical treatment of stapes fixation is to restore the impedance transfer of the ossicular chain and the acoustic impedance of the annular ligament of the stapes footplate to achieve normal physiologic vibration of the inner ear fluids. Advances in instrumentation, particularly the introduction of fiberoptic laser handpieces and microdrills, have enabled surgeons to approach this goal in a more precise and delicate fashion. In this article, the authors review their surgical techniques, the biophysics involved, the physics of fiberoptic handpieces for the delivery of argon laser energy, and their results.

Argon

Fiberoptic argon laser stapedotomy: is it safe?

The history of otosclerosis surgery has been marked by major advances in both surgical technique and instrumentation. Fenestration, stapes mobilization, total stapedectomy, and stapedotomy were important advances in technique. Loupes, binocular microscopy, speculum holders, and microdrills similarly advanced instrumentation. What about fiberoptic argon laser handpieces for use in laser stapedotomy? Do they represent a significant advance in instrumentation, or are they merely another gimmick? Are fiberoptic argon laser handpieces safe? Experimentally, the thermal effects of argon laser, delivered via fiberoptic handpieces to a cadaver stapes and model vestibule, were studied. No significant temperature elevations within a model vestibule were observed during stapedotomy. There were significant temperature elevations within the laser plume at the level of the facial nerve. These findings are consistent with our experience in over 2200 primary and revision stapedotomies. To date, there have been no cases of significant hearing loss or permanent facial paralysis related to the use of these fiberoptic handpieces. We believe fiberoptic argon laser handpieces are as safe as conventional microsurgical instruments in stapes surgery.

Ear Diseases

Functional use of the Nucleus 22-channel cochlear implant in the elderly.

A questionnaire was sent to 101 Nucleus 22-channel cochlear implant recipients aged 65 years and older to investigate the perceived impact of cochlear implantation on their quality of life. The questionnaire was designed to gain insight into the patient's daily use of the Nucleus implant. Sixty-seven questionnaires were returned over a 3-month period. The results of the survey showed that elderly cochlear implant patients obtained similar benefits to younger adult patients who were implanted with the same device. We believe that the results of this study will aid other centers when counseling elderly patients on the expected daily functional benefits of this device.

Aged

Argon laser stapedectomy using an endo-otoprobe system.

In summary, we believe that the endo-otoprobe system offers several advantages to the otologist. The system is safe and relatively inexpensive. The probes are designed to provide tactile feedback similar to that of standard otologic instruments and avoid the use of a cumbersome micromanipulator. There are currently shapes that are similar to a Rosen needle, Shea pick, and bayonet. We hope most otologists will find that one of the endo-otoprobes fits their particular style of surgery.

Humans

[Subcophosis and otosclerosis. Medical and surgical treatment].

The spiral ligament of the stria vascularis is nearly always damaged by otosclerotic foci when the patient is nearly totally deaf because of otosclerosis. Vascular drugs are to be prescribed in such a case, besides the Sodium Fluoride treatment. The Sodium Fluoride is, according to us, the best treatment to arrest the progression of the otosclerotic disease. Sodium fluoride will destroy the proteolytic enzymes damaging the inner ear membranes and the hair of the Corti hair cells.

Audiometry

[Gherini-Causse endo otoprobe and HGM argon laser. Value in the surgery of ear abnormalities].

Performing a stapedectomy in a slightly fixed otosclerotic footplate may induce an excessive motion of the labyrinthine fluids, damaging inner ear membranes and Corti hair cells fragilized by proteolytic enzymes. The fluid motion in the cochlear canal is quantic size only. The replacement of a slightly fixed footplate by an ideal compliance and impedance transmitting device, may allow the surgeon to get a tremendous improvement of hearing (as a Meniere disease). The Gherini-Causse multi-use endo-otoprobe combined with a HGM Argon Laser, if associated with a Skeeter Oto-tool drill, looks to be an efficient and safe solution to this otologic surgical challenge.

Argon

Mechanical work on the lungs and work of breathing with positive end-expiratory pressure and continuous positive airway pressure.

The mechanical work on the lung required during spontaneous breathing with positive end-expiratory pressure (PEEP) was compared with different methods of continuous positive airway pressure (CPAP) in nine young healthy athletes (surfers) at levels of 5, 10, 15, and 20 cm H2O. At the level of 20 cm H2O, PEEP increased the mean total work per minute by 116 percent and the total work per liter by 121 percent. The percent increase rose linearly with the level of PEEP. In contrast, with methods of CPAP that maintained the airway pressure (Paw) constant, the total work per minute decreased by 45 per cent at a PEEP of 10 cm H2O and remained at this level with PEEP of 15 and 20 cm H2O. Use of PEEP did not increase the functional residual capacity (FRC) in these spontaneously breathing subjects. In contrast, CPAP resulted in a rise in FRC proportional to the level of CPAP. This suggests that CPAP must be applied in a manner that maintains Paw constant to provide optimal assistance to ventilation.

Adult