Extra-oral implants: surgical procedures

The different extra-oral implant systems (screw and plate fixation) are not compatible. Rigorous surgical procedure (detailed and illustrated here) is mandatory to obtain the best implant osseointegration and epithesis loading 3 months later. Besides surgical procedure, careful bone and peri-abutment suture are required for success.     

Extra-oral implants: indications and contraindications

Osseointegrated facial prostheses are an interesting solution for maxillofacial rehabilitation when reconstructive surgery cannot be proposed. Progress in epithesis materials and in implantation techniques have renewed interest in maxillofacial prostheses. The best indications are for rehabilitation of nasal, auricular and orbitopalpebral defects. Another indication is complex loss of facial tissue. Endo-osseous epitheses are recommended mainly when there is no possibility of reasonable and satisfactory surgical reconstruction, when local carcinologic prognosis is uncertain, and to respond to the patient's demands. We detail here the precautions necessary when irradiation has been performed previously and finally present the contraindications against epitheses on osseointegrated implants.     

Extra-oral implants: principal areas of implantation

The success of extra-oral implants raises a certain number of technical and medical problems. Among these, the anatomy of the implant zone and bone quality are determining factors for osteointegration of the implants. We describe the principal zones of implantation detailing the risks involved in each area.     

Auditory brainstem implants: current neurosurgical experiences and perspective

The objective of this study was to present aspects of the current treatment protocol, such as patient evaluation and selection for therapy, multimodality monitoring for optimal auditory brainstem implant (ABI) positioning and radiological evaluation, that might have an impact on the functional results of ABI. Out of a series of 145 patients with bilateral vestibular schwannomas 10 patients received an ABI, eight of which are reported here. Patient selection was based on disease course, clinical and radiological criteria (according to the Hannover evaluation and prognosis scaling of neurofibromatosis type 2 (NF2)), extensive otological test battery and psycho-social factors. ABI placement was controlled by multimodality electrophysiological monitoring in order to activate the auditory pathway and to prevent false stimulation of the cranial nerve nuclei or long sensory or motor tracts. Results of hearing function were correlated with patients' ages, duration of deafness, tumour extension, tumour-induced compression or deformation of the brainstem, and numbers of activated electrodes without any side-effects. Out of 59 patients with pre-operative deafness eight patients received an ABI of the Nucleus 22 type. All these patients became continuous users without any side effects and experienced improved quality of life. Speech reception in combination with lip-reading was markedly improved, with further improvement over a long period. A short duration of deafness may be favourable for achieving good results, while age was not a relevant factor. Lateral recess obstruction may necessitate a more meticulous dissection, but did not prevent good placement of the ABI in the lateral recess. Pre-existing brainstem compression did not prevent good results, but brainstem deformation and ipsi- and contralateral distortion were followed by a less favourable outcome. Among the factors that can be influenced by the therapy management are the selection of patients with a slow progressing NF2 disease, a short duration of deafness, a careful analysis of brainstem deformation and consideration of either side for implantation. Long-standing brainstem deformation might not lead to recovery, but instead lead to a low number of active electrodes and possibly only moderate results. ABI treatment is a safe procedure that can increase a patient's quality of life considerably. ABI placement along with neurophysiological control helps to prevent side effects and to improve acoustic activation. Further studies on structural and functional changes of the brainstem after previous tumour compression and distortion should increase our understanding and facilitate a decision on the best side for ABI implantation.     

Tracheostomy in preterm infants: current trends

OBJECTIVE: To study the indications for and outcomes of tracheostomy in a population of preterm infants. DESIGN: Retrospective analysis of case records. SETTING: Two university-affiliated tertiary care children's hospitals.Patients We identified premature infants who required tracheostomies from January 1, 1997, through January 31, 2001. Information on weight, gestational age, comorbid conditions, indication for tracheostomy, and outcomes was collected. Infants were divided by birth weight into group 1 (<1000 g; n = 19 [very low birth weight]) and group 2 (> or =1000 g; n = 14). Comorbid conditions were scored and a total score was calculated for each patient. RESULTS: Group 1 had a higher incidence of patent ductus arteriosus, bronchopulmonary dysplasia, intraventricular hemorrhage, and retinopathy of prematurity. The incidence of congenital or genetic defects was equal in groups 1 and 2 (11 infants [58%] and 8 infants [57%], respectively). Group 1 had a higher average number of failed extubations (5.17 vs 3.18) and a higher oxygen requirement (48.7% vs 30.3%) compared with group 2. Weight at tracheostomy was essentially equal in groups 1 and 2 (3.6 vs 3.7 kg). Subglottic stenosis and laryngotracheomalacia were equally common findings in groups 1 and 2. The average comorbidity score for group 1 was higher than that for group 2 (6.7 vs 2.8). The most common indication for tracheostomy was ventilatory dependence (n = 24 [73%]), compared with airway obstruction (n = 6 [18%]) and pulmonary toilet (n = 3 [9%]). Overall, 6 patients (18%) had a complication related to the tracheostomy. CONCLUSIONS: Severity of pulmonary disease was the most significant factor associated with the need for tracheostomy in preterm infants. A tracheostomy can safely be performed in these infants with minimal morbidity.     

Reconstruction of the hypopharynx: current trends

PURPOSE OF REVIEW: Reconstruction of the hypopharynx continues to present a clinical challenge for the reconstructive surgeon. Trends continue to evolve as many viable options exist, depending on individual patient characteristics and institutional preferences. The article reviews the most current literature available on the subject. RECENT FINDINGS: Surgical resections resulting in pharyngoesophageal defects require timely reconstruction to minimize patient morbidity while optimizing quality of life, specifically in regards to speech and swallowing. Contemporary reconstructive options include various gastrointestinal flaps, pedicled myocutaneous flaps, and fasciocutaneous free flaps. Institutional trends often depend on the availability, training, and expertise of the reconstructive surgeon. The current options available differ in their complication rate and overall morbidity, and must take into account each patient's general medical health. Increased availability of surgeons trained in microvascular reconstruction and the continued high published success rates have made free flaps an attractive option for hypopharyngeal reconstruction. Functional outcome regarding swallowing and speech rehabilitation after free flap reconstruction is promising. SUMMARY: With continued publication of overall high success rates coupled with superior functional outcome and increased availability of surgeons trained in microvascular reconstruction, fasciocutaneous free flap reconstruction of the hypopharynx will probably surpass intestinal flaps in reliability and popularity.     

The current status of cochlear implants

In the University of Sydney cochlear implant programmes, 109 adults and teenagers have received a 22 electrode cochlear implant (Cochlear™ implant) since 1984; and 127 children have received a Cochlear™ implant since 1987. The results were analysed when all patients were still using the MSP speech processors rather than the newer SPEAK processors. Seventy five percent of adults and teenagers deafened after learning speech for a period of less than 15 years were able to recognise some words by audition alone. Only 30 percent of adults and teenagers deafened for over 15 years regaining hearing were able to recognise any words by audition alone but most found the device very helpful in aiding lipreading. None of adults and teenagers who were born deaf who received a cochlear implant found they could recognise any sounds and half of them abandoned using the device. Children who were deafened after learning speech usually did extremely well with a cochlear implant and could remain in their regular school situation. Children who had done well with hearing aids were also very likely to succeed with a cochlear implant. Children who had learnt to communicate by gestures or signs who had reached an age of over 6 years did poorly with the cochlear implant with 73 percent unable to recognise speech by listening alone and unable to improve their speech production to an intelligible level.     

Experimental and clinical audiology: current status and trends of development

The article presents results of experimental and clinical trials obtained in the National Research Center for Audiology and Hearing Rehabilitation and other leading research centers which studied mechanisms of primary auditory perception including cellular and membrane levels; nature of hair cell motor and electromotility, otoacoustic emission generation, effects of efferent system; nature and mechanisms underlying hereditary hypoacusis and deafness; regeneration of hair cells. Rehabilitation of deaf patients by means of cochlear implantation and optimization of universal audiological screening programs are described.     

Surgery of the facial nerve: current trends]

Recent operative variations in the surgery of the facial nerve are discussed through data from the literature and the author's personal experience. The analysis relates to two different situations: on the one hand the approach and preservation of an intact facial nerve in pathologies requiring the baring or freeing of the nerve; on the other hand, the operative attitude with respect to facial palsies requiring a decompression or repair of the nerve. The techniques are studied according to the intracranial, intrapetrosal or extracranial topography of the lesion. Extralabyrinthine transmastoid decompression is increasingly adopted in cases of intrapetrosal palsy. The different types of derouting and suture are discussed in the case of the solution of continuity of the nerve trajectory.     

Cochlear implants in young children: informed consent as a process and current practices

PURPOSE: This study examined the types of information that pediatric cochlear implant (PCI) centers and teams provide to parents of deaf children and the extent to which the informed consent process extends beyond medical issues to include social and cultural aspects. A second purpose was to determine the extent to which centers are applying selected new practices in cochlear implantation: younger age at implantation and bilateral implantation. METHOD: A 23-question survey was sent to 445 cochlear implant centers in the United States. Of the 445 centers contacted, 188 (42%) were excluded as ineligible (nonpediatric), 257 (58%) were determined eligible, and 121 (47%) of these completed the survey. Survey topics included characteristics of PCI centers and teams; the role and importance of professionals/consultants; types of medical, educational, Deaf culture, and identity information and perspectives provided to parents; and current practices regarding age of implantation and bilateral implantation. RESULTS: All of the PCI teams completing the survey presented medical/surgical risks, audiologic information, and variability of communication/educational options; fewer than half (45%) presented Deaf culture and emerging autonomy/identity issues to parents. Most PCI centers felt the optimal age to implant a child was 10-15 months. The majority of PCI centers, regardless of affiliation with a teaching hospital, responded that they rarely or never implanted bilaterally, and few discussed bilateral implants with parents. CONCLUSIONS: Audiologists are the only nonsurgical professionals always represented on the cochlear implant team. In order to best prepare audiologists for this role, graduate audiology programs need to address more extensively the Deaf culture and perspective, as well as genetics of hearing loss. Increased attention to educational audiology and evidence-based research regarding best age to implant and bilateral implantation needs to be included in the discussion with parents. Audiologists play a crucial role in informing parents and coordinating care, and should therefore carefully consider their role in the informed consent process.     

Dynamic current focusing for loudness encoding in cochlear implants: a take-home trial

Objective: This study aimed to evaluate a more energy-efficient dynamic current focussing (DCF) speech-processing strategy after long-term listening experience. In DCF, tripolar stimulation is used near the threshold and loudness is controlled by the compensation coefficient σ. A recent acute pilot study showed improved spectral-temporally modulated ripple test (SMRT) scores at low loudness levels, but battery life was reduced to 1.5–4?hours.

Design: Within-subject comparisons were made for the clinical versus. DCF strategy after 5?weeks of at-home usage. Speech intelligibility in noise, spectral ripple discrimination, temporal modulation detection, loudness growth, and subjective ratings were assessed.

Study sample: Twenty HiRes90K (Advanced Bionics, Valencia, USA) cochlear implant (CI) users.

Results: Average battery life was 9?hours with the newly implemented DCF compared to 13.4?hours with the clinical strategy. Compared with measurements made at the beginning of the study, SMRT-scores and speech intelligibility in noise were significantly improved with DCF. However, both measures suffered from unexpected learning effects over time. The improvement disappeared and speech intelligibility in noise declined significantly relative to the final control measurement with the clinical strategy.

Conclusion: Most CI users can adapt to the DCF strategy in a take-home setting. Although DCF has the potential to improve performance on the SMRT test, learning effects complicate the interpretation of the current results.     

Langerhans' cell histiocytosis: current trends and the role of the head and neck surgeon

Langerhans' cell histiocytosis (LCH)--once called histiocytosis X--is a complex reticuloendothelial disease that often involves the head and neck. We discuss the current nomenclature of this disease and review its pathologic and clinical characteristics, with particular emphasis on the role of the head and neck surgeon. LCH can be challenging to diagnose, and the otolaryngologist must be familiar with its varied presentations. Because LCH usually responds well to medical therapy and extensive resection can easily cause more morbidity than the disease itself, a minimalist approach to treatment usually provides the best outcome. We also discuss the case of a 9-month-old girl with LCH who presented with aggressive head and neck disease.     

Perspectives of adults with cochlear implants on current CI services and daily life

This paper reports on a survey and interviews carried out with adults who have gone through the cochlear implantation pathway. It explores their experiences of current services, the assessment process for implantation, and the impact on their daily lives, including views and experiences on communication, independence and confidence. It also explores, in today's financially challenging climate, their awareness of current funding issues and the value of their implant to them.     

Current steering and current focusing in cochlear implants: comparison of monopolar, tripolar, and virtual channel electrode configurations

OBJECTIVES: To compare the effects of Monopole (Mono), Tripole (Tri), and "Virtual channel" (Vchan) electrode configurations on spectral resolution and speech perception in a crossover design. DESIGN: Nine experienced adults who received an Advanced Bionics CII/90K cochlear implant participated in a crossover design using three experimental strategies for 2 wk each. Three strategies were compared: (1) Mono; (2) Tri with current partly returning to adjacent electrodes and partly (25 or 75%) to the extracochlear reference; and (3) a monopolar "Vchan" strategy creating seven intermediate channels between two contacts. Each strategy was a variant of the standard "HiRes" processing strategy using 14 channels and 1105 pulses/sec/ channel, and a pulse duration of 32 microsec/phase. Spectral resolution was measured using broadband noise with a sinusoidally rippled spectral envelope with peaks evenly spaced on a logarithmic frequency scale. Speech perception was measured for monosyllables in quiet and in steady-state and fluctuating noises. Subjective comments on music experience and preferences in everyday use were assessed through questionnaires. RESULTS: Thresholds and most comfortable levels with Mono and Vchan were both significantly lower than levels with Tri. Spectral resolution was significantly higher with Tri than with Mono; spectral resolution with Vchan did not differ significantly from the other configurations. Moderate but significant correlations between word recognition and spectral resolution were found in speech in quiet and fluctuating noise. For speech in quiet, word recognition was best with Mono and worst with Vchan; Tri did not significantly differ from the other configurations. Pooled across the noise conditions, word recognition was best with Tri and worst with Vchan (Mono did not significantly differ from the other configurations). These differences were small and insufficient to result in a clear increase in performance across subjects if the result from the best configuration per subject was compared with the result from Mono. Across all subjects, music appreciation and satisfaction in everyday use did not clearly differ between configurations. CONCLUSIONS: (1) Although spectral resolution was improved with the tripolar configuration, differences in speech performance were too small in this limited group of subjects to justify clinical introduction. (2) Overall spectral resolution remained extremely poor compared with normal hearing; it remains to be seen whether further manipulations of the electrical field will be more effective.     

Skeletal volume enhancement: implants and osteotomies

PURPOSE OF REVIEW: Facial plastic surgeons are concerned with improving or restoring function and form. Most surgeons perform primarily soft tissue procedures, which alone are often sufficient. However, deficiencies in the underlying craniomaxillofacial skeleton must also be addressed. Facial skeletal augmentation remains an essential aspect of cosmetic and reconstructive surgery. This article reviews the basic alloplastic biomaterials available for facial volume enhancement, discusses the zygomatic sandwich osteotomy for malar augmentation, and describes recent applications of distraction osteogenesis in the craniomaxillofacial region. An update in tissue engineering and computer modeling is also provided. RECENT FINDINGS: High-porosity expanded polytetrafluoroethylene has been developed to provide a softer feel with less shrinkage and migration because of better biointegration and cellular ingrowth. Long-term results with porous polyethylene have demonstrated superior biocompatibility and minimal complications. Hydroxyapatite cement has been associated with an immunoguided delayed inflammatory reaction that leads to thinning of the overlying skin and exposure of the implant.Applications of distraction osteogenesis are rapidly expanding and include deformities of the mandible, midface, and cranium. There has been a trend toward the use of internal hardware, and internal devices are being developed to deliver a greater degree of vector control. Biodegradable devices have been developed to eliminate the second surgical procedure necessary for hardware removal. In the future, successful tissue engineering could eliminate many of the drawbacks associated with implants and osteotomies. The ability to stimulate stem cells to generate autogenous bone has been demonstrated in the laboratory. A novel application of computer technology that integrates laser surface scanning and digitizing with computer-aided design and manufacturing to produce facial prostheses has been described. SUMMARY: An abundance of alternatives exist for skeletal volume enhancement including alloplastic implants, standard osteotomies, and distraction osteogenesis. The surgeon must evaluate the pros and cons of each technique in the context of each individual patient to determine the most appropriate option. Technologic advances in biomaterials, distraction hardware, computer modeling, and tissue engineering will continue to supply the surgeon's repertoire with improved methods to augment and restore the craniomaxillofacial skeleton.     

A critical analysis of current trends in the management of Bell's palsy.

The treatment of Bell's palsy has been a controversial subject for many years. During the past 10 years 152 papers pertaining to this affection of the facial nerve have apperaed in the American literature. Ninety-seven of these were general discussions of the etiology, pathology, prognosis and treatment of this condition: 20 were concerned with ascertaining the status of the facial nerve by electrical tests and four with the activity of the chorda tympani nerve in patients with Bell's palsy. The remaining 31 articles specifically discussed the treatment of Bell's palsy. As a result of this obvious interest in Bell's palsy, one would expect that the treatment of this affection of the facial nerve would be more or less uniform at this time. This is not the case, however, for the literature demonstrates it to be in a state of flux. Although steroid therapy has replaced other regimens of medical therapy to a large extent, surgical intervention still has its proponents. It is interesting to note that at the time of this review of the literature, no report of a controlled, double-blind study of the efficacy of steroid therapy for Bell's palsy has appeared in the American literature.