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Derald E Brackmann

Publications and source records attributed to Derald E Brackmann.

17 recordsLinked to original sources
PubMed2006

Chondrosarcoma of the skull base: long-term follow-up.

OBJECTIVE: Chondrosarcoma of the skull base is an uncommon neoplasm comprising 0.15% of all intracranial tumors and 6% of skull base neoplasms. The outcome of treatment is difficult to assess because the slow growth rate means that there is a long interval before detecting the recurrence. We describe the use of lateral skull base techniques for these lesions and examine the long-term outcomes. The pathological features, radiological findings, and radiotherapy options are also discussed. STUDY DESIGN: Retrospective case review with current follow-up where possible. SETTING: Tertiary referral neurotologic private practice. PATIENTS: Eight patients with histologically confirmed skull base chondrosarcoma operated on since 1979. At the time of the surgery, the five women and three men ranged in age from 31 to 63 years, with a mean of 42.9 years. The follow-up ranged from 9 months to 25 years and 5 months. INTERVENTIONS: All patients underwent surgical removal; the earliest patient underwent surgical removal via transcochlear and retrosigmoid approaches, and seven via an infratemporal fossa approach, with or without exenteration of the otic capsule. MAIN OUTCOME MEASURES: Number of patients with residual and recurrent tumors. RESULTS: In the patient who underwent surgery via the transcochlear approach, recurrence was noted within 3 months, and new exploration using the retrosigmoid approach was performed for the removal of the recurrent lesion. This patient showed no signs of recurrence for 25 years since last surgery. Of the seven patients who underwent surgery via the infratemporal fossa approach, one had residual tumor found at 1 year, but remained alive and well for 21 years after the surgery. The other six had gross total resection and showed no signs of recurrence at the last known follow-up. One patient died as a result of an unrelated cause 18 years after surgery for the chondrosarcoma. CONCLUSION: The gross total resection of these lesions is possible because of the evolution of lateral skull base techniques and can be routinely accomplished with the infratemporal fossa approach. The improved exposure afforded by this approach seems to have resulted in more complete extirpation of the tumor and a decrease in the recurrence rate.

Adult↗
PubMed2006

Auditory brainstem implants: surgical aspects.

Patients with neurofibromatosis type 2 often develop bilateral life-threatening vestibular schwannoma necessitating tumor removal, which results in deafness. We developed the auditory brainstem implant (ABI) in order to be able to electrically stimulate the cochlear nucleus complex in patients with bilateral cochlear nerve injury from bilateral schwannoma. After tumor removal, the electrode array of the ABI is inserted into the lateral recess of the fourth ventricle and placed over the surface of the ventral and dorsal cochlear nuclei. The ABI is designed to stimulate auditory neural structures within the cochlear nucleus in order to convey salient cues about the frequency, amplitude, and temporal characteristics of sounds. To date, more than 200 patients have received an ABI device at our institution. Recently, penetrating ABIs were introduced, and preliminary results of penetrating ABIs are discussed in this paper. The surgical anatomy of the nucleus and surgical placement of the ABI in patients with neurofibromatosis type 2 are described, and surgical considerations in this group of challenging patients are detailed.

Auditory Brain Stem Implants↗
PubMed2005

Neurotologic skull base surgery in pediatric patients.

OBJECTIVE: Innovations in diagnosis, surgical techniques, and perioperative care have dramatically improved outcomes in lateral skull base procedures in recent years. There is a belief, however, that children with skull base tumors have yet to benefit from these technological and procedural advances. The purpose of this study is to provide a clinical review of neurotologic skull base surgery in the pediatric population. STUDY DESIGN: Retrospective case review. SETTING: Private practice tertiary referral center. PATIENTS: Eighty-nine pediatric patients undergoing 115 neurotologic procedures for lateral skull base tumors from July 1992 to September 2003. MAIN OUTCOME MEASURES: Initial clinical presentation, tumor type, pre- and postoperative hearing and facial nerve status, treatment course, complications, and functional outcomes. RESULTS: The majority of tumors in this series were vestibular schwannomas, and 65 patients were diagnosed with neurofibromatosis Type 2. Surgical approaches included 70 middle fossa, 40 translabyrinthine, 2 transcochlear, 2 infratemporal fossa, and 1 retrosigmoid craniotomy. Complete tumor removal was accomplished in the majority of cases (97%), with good preservation of facial nerve function (House-Brackmann Grade I or II) in 80% of patients. In patients undergoing middle fossa surgery for hearing preservation, measurable hearing was preserved in 61.4% of cases. The incidence of complications was low. CONCLUSION: With advances in diagnostic procedures and use of current neurotologic techniques, pediatric patients may undergo successful treatment of lateral skull base tumors, with good functional outcomes and minimal morbidity.

Adolescent↗
PubMed2005

Surgical salvage after failed irradiation for vestibular schwannoma.

OBJECTIVES/HYPOTHESIS: Compare vestibular schwannoma (VS) surgical outcome between patients with prior irradiation and those not previously treated. STUDY DESIGN: Retrospective review with matched control group. METHODS: Review of tumor adherence to the facial nerve, facial nerve grade, and complications in 38 patients with radiotherapy as a primary procedure before VS surgical removal and a matched random sample of 38 patients with primary surgery. The majority of the irradiated group had gamma knife radiation therapy. Mean time from irradiation to surgical salvage was 3.3 years (SD = 3.2), with a minimum of 5.2 months and a maximum of 15.8 years. Most (89.5%) patients in each group underwent a translabyrinthine approach. Mean tumor size at surgery was 2.6 cm in each group. RESULTS: The irradiated group had more moderate to severe adherence of tumor than the controls (89% vs. 63%, P < or = .01). They also had a lower rate of good facial function (House-Brackmann grade I/II) (37% vs. 70%) and a higher rate of poor function (grades V or VI) (50% vs. 18%) at follow-up (P < or = .019). Results were similar when including only those with good preoperative function (50% vs. 72% and 32% vs. 15%) but did not achieve statistical significance. Surgical time and complications did not differ. CONCLUSION: Patients who have undergone irradiation for VS and require surgical salvage may have a more difficult surgery and poorer outcomes than those not previously irradiated. When making their initial choice of treatment, patients should be counseled that surgery might be more difficult after failed stereotactic irradiation.

Adult↗
PubMed2004

Auditory brainstem implantation in 12- to 18-year-olds.

OBJECTIVE: To assess the effects of the side of implantation (first-side vs second-side vestibular schwannoma); the presence of nonauditory sensations; the general health, expectations, and motivation of the patients; and a support group on the use of a multichannel auditory brainstem implant (ABI) in 12- to 18-year-old patients with neurofibromatosis 2. DESIGN: Since 1992, 21 individuals (age range, 12-18 years) who were deafened by neurofibromatosis 2 have undergone implantation with a multichannel ABI at the House Ear Institute, Los Angeles, Calif. The patients were categorized regarding side of implantation, presence of remaining hearing (in first-side implant recipients), incidence of nonauditory sensations, and ABI use or nonuse. They were also rated on factors of general health, personal motivation, expectations, and family support. RESULTS: Nineteen (95%) of 20 teenagers tested received hearing sensations from their ABIs. Eleven teenagers used their ABIs regularly, but 8 did not. Of the nonusers, 2 had good remaining hearing on the side with the second vestibular schwannoma, 2 had persistent nonauditory sensations, and 4 became program dropouts. None of the dropouts had remaining hearing, significant nonauditory sensations, or poor health; however, they generally rated poorly in terms of personal motivation, expectations, and family support. One patient with good family support returned with excellent ABI results after 4 years' absence. CONCLUSIONS: The multichannel ABI is an effective means of providing hearing sensations to young patients deafened by neurofibromatosis 2. Preoperative counseling regarding the importance of such factors as expectations, personal motivation, and family support is invaluable and can promote successful adaptation to the device. With patience and support, even young nonusers (including program dropouts) can become successful device users.

Adolescent↗
PubMed2004

The evolution of surgical approaches for posterior fossa meningiomas.

OBJECTIVE: To evaluate surgical outcomes for the treatment of posterior fossa meningiomas at the House Ear Clinic from 1987 to 2001. We review our current treatment algorithm and present our postoperative outcomes with attention to facial and auditory neural preservation. STUDY DESIGN: Retrospective review. SETTING: Tertiary care center. PATIENTS: Medical records of 71 patients who underwent posterior fossa meningioma surgery at the House Ear Clinic were reviewed. INTERVENTION: All patients had surgical removal of their meningioma via translabyrinthine, transcochlear, retrosigmoid, extended middle fossa, or combined petrosal approaches by House Ear Clinic neurotologists and neurosurgeons. MAIN OUTCOME MEASURES: Preoperative and postoperative auditory and facial nerve function data were collected. Patient and tumor characteristics including presenting symptoms, completion of tumor resection, and complications secondary to surgery were also recorded. RESULTS: The most common presenting symptoms in this series were otologic, with hearing loss (61%), tinnitus (58%), and imbalance (58%) as the three most common. Gross total resection was achieved in 67 (94%) patients. Hearing-preservation surgery was attempted in 37 (52%) patients (68% via extended middle fossa or combined approach). Twenty-one patients with preoperative Class A hearing had follow-up audiometric data and 18 (86%) had serviceable hearing preserved. Excluding transcochlear craniotomies, 85% of patients had normal facial nerve function postoperatively. Cerebrospinal fluid leak (6%) was the most common complication. CONCLUSIONS: Advances in microsurgical techniques have greatly changed our management of patients with posterior fossa meningiomas. These changes have reduced postoperative morbidity. Specifically, use of the anterior and posterior petrosal approaches has facilitated facial and auditory neural preservation while not compromising the extent of tumor excision.

Algorithms↗
PubMed2004

The multichannel auditory brainstem implant: how many electrodes make sense?

OBJECT: Development of multichannel auditory brainstem implant (ABI) systems has been based in part on the assumption that audiological outcome can be optimized by increasing the number of available electrodes. In this paper the authors critically analyze this assumption on the basis of a retrospective clinical study performed using the Nucleus 22 ABI surface electrode array. METHODS: The perceptual performances of 61 patients with neurofibromatosis Type 2 were tested approximately 6 weeks after an eight-electrode ABI had been implanted. Of eight implanted electrodes 5.57 +/- 2.57 (mean +/- standard deviation [SD] provided auditory sensations when stimulated. Electrodes were deactivated when stimulation resulted in significant nonauditory side effects or no auditory sensation at all, and also when they failed to provide distinctive pitch sensations. The mean (+/- SD) scores for patients with ABIs were the following: sound-only consonant recognition, 20.4 +/- 14.3 (range 0-65%); vowel recognition, 28.8 +/- 18% (range 0-67%); Monosyllable Trochee Spondee (MTS) word recognition 41.1 +/- 25.3% (range 0-100%); and sentence recognition, 5.3 +/- 11.4% (range 0-64%). Performance in patients in whom between one and three electrodes provided auditory sensation was significantly poorer than that in patients with between four and eight functional electrodes in the vowel, MTS word, and City University of New York (CUNY) sentence recognition tests. The correlation between performance and electrode number did not reach the 0.05 level of significance with respect to the sound effect, consonant, and MTS stress-pattern recognition tests, probably because a satisfactory performance in these tests can be obtained only with temporal cues, that is, without any information about the frequency of the sounds. In the MTS word and the CUNY sentence recognition tests, performance was optimal in the patients with eight functional electrodes. Although all top performers had more than three functional auditory electrodes, no further improvement (asymptotic performance) was seen in those with five or more active electrodes in the consonant, vowel, and sound effect recognition tests. CONCLUSIONS: A minimum of three spectral channels, programmed in the appropriate individual tonotopic order seem to be required for satisfactory speech recognition in most patients with ABI. Due to the limited access to the tonotopic frequency gradient of the cochlear nucleus with surface stimulation, patients with ABI do not receive a wide range of spectral cues (frequency information) with multielectrode (> 5) surface arrays.

Acoustic Stimulation↗
PubMed2003

Long-term hearing preservation after middle fossa removal of vestibular schwannoma.

OBJECTIVE: We sought to determine long-term hearing preservation in vestibular schwannoma patients after undergoing middle fossa resection. STUDY DESIGN, SETTING, AND OUTCOME MEASURES: We conducted a retrospective chart review of patients undergoing middle fossa resection from 1990 to 1995 at a tertiary care center. Pure-tone thresholds, before resection and at least 5 years after resection, and speech discrimination scores are reported. RESULTS: Seventy percent of patients with immediate postoperative hearing maintained serviceable hearing at more than 5 years after surgery. Pure-tone average in the operative ear changed at the same rate as hearing in the unoperated ear during this follow-up period. CONCLUSIONS: More than two thirds of patients who underwent middle fossa resection of a vestibular schwannoma with some hearing postoperatively maintain that hearing at greater than 5 years of follow-up. Surgery alone does not have a negative impact on long-term hearing preservation.

Adult↗
PubMed2003

Transcranial contralateral cochlear stimulation in unilateral deafness.

OBJECTIVES: The purpose of this study is to evaluate the effectiveness of Bone Anchored Cochlear Stimulator (BAHA) in transcranial routing of signal by implanting the deaf ear. Study design and settings Eighteen patients with unilateral deafness were included in a multisite study. They had a 1-month pre-implantation trial with a contralateral routing of signal (CROS) hearing aid. Their performance with BAHA was compared with the CROS device using speech reception thresholds, speech recognition performance in noise, and the Abbreviated Profile Hearing Benefit and Single Sided Deafness questionnaires. RESULTS: Patients reported a significant improvement in speech intelligibility in noise and greater benefit from BAHA compared with CROS hearing aids. Patients were satisfied with the device and its impact on their quality of life. No major complications were reported. Conclusion and significance BAHA is effective in unilateral deafness. Auditory stimuli from the deaf side can be transmitted to the good ear, avoiding the limitations inherent in CROS amplification.

Acoustic Stimulation↗
PubMed2003

Use of a multichannel auditory brainstem implant for neurofibromatosis type 2.

Neurofibromatosis type 2 (NF 2) typically results in deafness due to disruption of the cochlear nerves, making peripheral devices such as cochlear implants ineffective. Auditory brainstem implants (ABIs), for direct electrical stimulation of the cochlear nucleus, have been used to provide auditory stimulation in this group of patients. Currently, 141 patients have been implanted in our institution, most recently using an advanced multichannel device. We report results of a recent series of 86 patients who received ABIs. Of this group, 60 had successful implantation, recovered from surgery, responded successfully to stimulation and underwent a full course of device programming and audiologic testing. This group had significant improvement in scores on several audiologic tests compared to baseline. When used to augment lip reading, improvement was also seen. The degree of improvement varied considerably among patients. ABI is a useful device for deaf patients with NF 2. As measured by audiologic testing, many patients receive substantial benefit with regard to sound and speech comprehension.

Brain Stem↗
PubMed2003

Lipochoristomas (lipomatous tumors) of the acoustic nerve.

CONTEXT: Lipochoristomas (lipomatous choristomas) are rare tumors of the acoustic nerve (cranial nerve VIII/vestibulocochlear nerve) within the internal acoustic canal and sometimes the cerebellopontine angle, and are histogenetically believed to be congenital malformations. Their clinically indolent behavior has recently prompted a more conservative management protocol in a quest for maximal nerve/hearing preservation. This approach contrasts sharply with that for the common internal acoustic canal/cerebellopontine angle tumors, the neuroepithelial neoplasms (acoustic schwannomas and meningiomas), which behave more aggressively and have more prominent clinical manifestations. Owing to their rarity, the clinicopathologic features of cranial nerve VIII lipochoristomas have been obtained mainly through case reports. OBJECTIVE: We present the clinicopathologic features of 11 cases of lipochoristomas of cranial nerve VIII. DESIGN: The 11 cases were documented between 1992 and 2003. We performed complete clinical reviews with histologic, histochemical, and immunohistochemical analyses of formalin-fixed, paraffin-embedded tumor samples. RESULTS: The patients were 8 men and 3 women with hearing loss of the right ear (5 patients) or the left ear (6 patients). No patient had bilateral tumors. All lipochoristomas histologically possessed mature adipose tissue admixed with varied amounts of mature fibrous tissue, tortuous thick-walled vessels, smooth muscle bundles, and skeletal muscle fibers, the latter verified with immunohistochemistry. CONCLUSIONS: The histomorphologic and immunophenotypic evidence showed that these tumors are better characterized as choristomas than as simple "lipomas," as they have been labeled in the past. Their overall nonaggressive clinical nature in addition to the characteristic radiologic and histomorphologic findings are important clinicopathologic features for the pathologist to recognize and differentiate, especially during frozen section evaluations, in order to direct the neurosurgeon to a more appropriate conservative therapeutic intervention.

Adult↗
PubMed2002

Surgical management of petrous apex cholesterol granulomas.

OBJECTIVES: To review surgical approaches for drainage of petrous apex cholesterol granulomas, define the criteria for the selection of each approach, and identify factors affecting surgical outcome. STUDY DESIGN: Retrospective chart review and follow-up survey questionnaire. SETTING: Tertiary neurotologic referral center. PATIENTS: Thirty-four patients who underwent surgical treatment for symptomatic cholesterol granulomas of the petrous apex, who had a minimum of 3 months of clinical follow-up care and, in some cases, postoperative radiologic follow-up studies. INTERVENTION: Drainage with or without removal of the cyst lining was achieved through the transcanal infracochlear, transmastoid infralabyrinthine, middle fossa, translabyrinthine, and transotic approaches. Silastic catheters were used to stent drainage sites in some cases. MAIN OUTCOME MEASURES: Relief of symptoms, postoperative cranial nerve function, clinical and radiologic recurrence, and need for further surgical intervention were evaluated. Imaging studies were reviewed to determine how anatomic information influenced surgical decisions and outcome. RESULTS: Clinical improvement of symptoms was observed in 28 patients (82%), and recovery of cranial nerve function was observed in 8 of 9 affected individuals. Serviceable hearing was preserved in all but 1 patient. Five patients required revision surgery for recurrent symptoms and lesions. All 5 patients had undergone drainage procedures without the use of stents. The size of the lesion did not influence the surgical outcome. CONCLUSIONS: Determination of the appropriate surgical approach to the petrous apex is based on hearing status in the affected ear and on the anatomic relationships between the lesion and the surrounding neurovascular structures. The translabyrinthine approach is useful in nonhearing ears. In hearing individuals, anatomy permitting, the transcanal infracochlear approach with stenting is the preferred approach for drainage of petrous apex cholesterol granulomas.

Adolescent↗
PubMed2002

Immortalization of normal adult human middle ear epithelial cells using a retrovirus containing the E6/E7 genes of human papillomavirus type 16.

A human middle ear epithelial cell line (HMEEC-1) was established using human papillomavirus E6/E7 genes. HMEEC-1 has remained morphologically and phenotypically stable, even after 50 passages. The cells are anchorage-dependent and nontumorigenic when injected into nude mice. This cell line thus provides a new tool for the study of normal cell biology and the pathological processes associated with the epithelial cells of the middle ear in otitis media. HMEEC-1 will also be useful in the search for new drugs and biological agents for the treatment of otitis media.

Adult↗
PubMed2002

Multichannel auditory brainstem implant: update on performance in 61 patients.

OBJECT: Neurofibromatosis Type 2 (NF2) has typically resulted in deafness after surgical removal of bilateral vestibular schwannomas (VSs). Cochlear implants are generally ineffective for this kind of deafness because of the loss of continuity in the auditory nerve after tumor removal. The first auditory brainstem implant (ABI) in such a patient was performed in 1979 at the House Ear Institute, and this individual continues to benefit from electrical stimulation of the cochlear nucleus complex. In 1992, an advanced multichannel ABI was developed and a series of patients with NF2 received this implant to study the safety and efficacy of the device. METHODS: At the time of first- or second-side VS removal, patients received an eight-electrode array applied to the surface of the cochlear nucleus within the confines of the lateral recess of the fourth ventricle. The device was activated approximately 6 weeks after implantation. and patients were tested every 3 months for the 1st year after the initial stimulation, and annually thereafter. The protocol included a comprehensive battery of psychophysical and speech perception tests. CONCLUSIONS: The multichannel ABI proved to be effective and safe in providing useful auditory sensations in most patients with NF2. The ABI improved patients' ability to communicate compared with the lipreading-only condition, it allowed the detection and recognition of many environmental sounds, and in some cases it provided significant ability to understand speech by using just the sound from the ABI (with no lipreading cues). Its performance in most patients has continued to improve for up to 8 years after implantation.

Adolescent↗
PubMedDate not supplied

Growth of postoperative remnants of unilateral vestibular nerve schwannoma: role of the vestibular ganglion.

Histopathological examination of seven temporal bones from patients who underwent a removal of vestibular nerve schwannomas by the translabyrithine or middle fossa approaches has demonstrated small tumor remnants that failed to grow as long as 25 years after surgery. In spite of the high incidence of residual tumors, the clinical recurrence rate of tumors operated at our institution by the translabyrinthine or middle fossa approaches is low (0.3%). Immunohistochemical labeling of dividing cells demonstrated that segments of tumor adjacent to the vestibular nerve and ganglion contained more dividing cells than were present in areas of the tumor at a distance from them.

Aged↗