Methylprednisolone applied directly to the round window reduces dizziness after cochlear implantation: a randomized clinical trial.

This prospective, double-blind controlled, randomized clinical trial of 43 adults showed that topical methylprednisolone applied to the round window during cochlear implantation was effective in protecting inner ear function. Postoperative vestibular disturbance was significantly lower in the steroid group (5%) than the control group (29%). Electrode impedances from the middle portion of the electrode array (electrodes 10-13) were significantly reduced in steroid-treated recipients compared to controls. Hearing and vestibular function analyses were under-powered to detect any drug changes due to limited participant data.

Scalar localisation of peri-modiolar electrodes and speech perception outcomes.

OBJECTIVE: To identify the intracochlear electrode position in cochlear implant recipients and determine the correlation to speech perception for two peri-modiolar electrode arrays. METHODS: Post-operative cone-beam computed tomography images of 92 adult recipients of the 'CI512' electrode and 18 adult recipients of the 'CI532' electrode were analysed. Phonemes scores were recorded pre-implantation, and at 3 and 12 months post-implantation. RESULTS: All CI532 electrodes were wholly within scala tympani. Of the 79 CI512 electrodes intended to be in scala tympani, 58 (73 per cent) were in scala tympani, 14 (17 per cent) were translocated and 7 (9 per cent) were wholly in scala vestibuli. Thirteen CI512 electrodes were deliberately inserted into scala vestibuli. Speech perception scores for post-lingual recipients were higher in the scala tympani group (69.1 per cent) compared with the scala vestibuli (54.2 per cent) and translocation (50 per cent) groups (p < 0.05). Electrode location outside of scala tympani independently resulted in a 10.5 per cent decrease in phoneme scores. CONCLUSION: Cone-beam computed tomography was valuable for demonstrating electrode position. The rate of scala tympani insertion was higher in CI532 than in CI512 electrodes. Scala vestibuli insertion and translocation were associated with poorer speech perception outcomes.

Co-registration of cone beam CT and preoperative MRI for improved accuracy of electrode localization following cochlear implantation.

OBJECTIVES: To investigate the clinical usefulness and practicality of co-registration of Cone Beam CT (CBCT) with preoperative Magnetic Resonance Imaging (MRI) for intracochlear localization of electrodes after cochlear implantation. METHODS: Images of 20 adult patients who underwent CBCT after implantation were co-registered with preoperative MRI scans. Time taken for co-registration was recorded. The images were analysed by clinicians of varying levels of expertise to determine electrode position and ease of interpretation. RESULTS: After a short learning curve, the average co-registration time was 10.78 minutes (StdDev 2.37). All clinicians found the co-registered images easier to interpret than CBCT alone. The mean concordance of CBCT vs. co-registered image analysis between consultant otologists was 60% (17-100%) and 86% (60-100%), respectively. The sensitivity and specificity for CBCT to identify Scala Vestibuli insertion or translocation was 100 and 75%, respectively. The negative predictive value was 100%. DISCUSSION: CBCT should be performed following adult cochlear implantation for audit and quality control of surgical technique. If SV insertion or translocation is suspected, co-registration with preoperative MRI should be performed to enable easier analysis. There will be a learning curve for this process in terms of both the co-registration and the interpretation of images by clinicians.

Serum elimination half-life of tamoxifen and its metabolites in patients with advanced breast cancer.

In breast cancer patients discontinuing chronic tamoxifen therapy, the serum elimination of metabolites X, Y and E paralleled that of tamoxifen, whereas that of metabolite Z did not. The serum elimination of tamoxifen and metabolites X and B was increased by amino-glutethimide treatment, whereas that of metabolites Z, Y, and E was not.

Serum and urine levels of tamoxifen and its metabolites in patients with advanced breast cancer after a loading dose and at steady-state levels.

PURPOSE: To compare serum and urine levels of tamoxifen and metabolites after a loading dose and at the steady state. METHODS: A loading dose of 160 mg of tamoxifen was given to 14 patients with advanced breast cancer. Thereafter a regular daily dose of 30 mg of tamoxifen was given. Serum and urine levels of tamoxifen and metabolites were measured by high-performance liquid chromatography and compared with levels determined in 31 patients with advanced breast cancer at the steady state at a daily dose of 30 mg of tamoxifen. RESULTS: Serum and urine levels (24-h values) of tamoxifen and metabolites were lower (P < 0.05) after a loading dose than at the steady state. The difference was most pronounced for the metabolites, whereas the tamoxifen loading-dose level was near the steady state. CONCLUSION: Tamoxifen steady state can be reached in 1-2 days by the administration of a loading dose of 160 mg of tamoxifen for 2 days. Tamoxifen metabolite steady-state levels are reached regularly after 4 or more weeks during application of a loading dose. Very little tamoxifen or metabolites are excreted into the urine.

Translabyrinthine removal of large acoustic neuromas.

Several surgical approaches to the cerebellopontine angle and internal auditory canal have been developed for the removal of acoustic neuromas. The choice of an approach may be influenced by hearing levels and tumor size. We reviewed the records of the primary translabyrinthine removal of 167 large (> or = 4 cm) acoustic neuromas performed between 1982 and 1990. Patients ranged in age from 15 to 83 years, with a mean of 43 years (male, 49%; female, 51%). Total removal was achieved in 95%. The facial nerve was preserved anatomically intact in 91%. At follow-up (mean, 2.1 yr), facial nerve function was acceptable (Grades I-IV) in 75% and good (Grades I-II) in 42%. Vascular complications occurred in 4.8%; however, there were no deaths. A cerebrospinal fluid leak occurred in 9.6% of cases, and meningitis occurred in 8.3%. In patients with large tumors where there is little chance to preserve preoperative hearing, we have successfully used the translabyrinthine approach for total tumor removal. The advantages and disadvantages of both the translabyrinthine and suboccipital approaches are discussed.

Comprehensive management of bilateral acoustic neuromas. Current perspectives.

Bilateral acoustic neuromas are pathognomonic for neurofibromatosis 2. Patients with neurofibromatosis 2 present complex and challenging management problems, because growth or surgical removal of the acoustic neuroma may result in total hearing loss. Early diagnosis with gadolinium-enhanced magnetic resonance imaging and refinements in hearing preservation surgery have improved our ability to prevent total hearing loss. For patients with larger tumors or no useful hearing, the auditory brain-stem implant allows restoration of some auditory function when the tumor is removed. We describe our management strategy for patients with bilateral acoustic neuromas, and present case reports to show their diversity. We also discuss the newly identified neurofibromatosis 2 tumor suppressor gene.

Nuclear morphometry for prediction of metastatic potential in early squamous cell carcinoma of the floor of the mouth.

Quantitative morphometric analyses of the nuclear shape have been successfully used with prostatic carcinoma to predict tumor metastatic potential and provide the most sensitive indicator of tumor aggressiveness in the individual case. We have studied the nuclear morphometric characteristics of 22 patients with T1 and T2 squamous cell carcinoma of the floor of the mouth to see if a correlation existed between lack of nuclear roundness and presence of cervical metastatic disease. A significant difference was identified between the morphology of cancer cell nuclei and normal squamous epithelium. Nuclear morphology could not be used to distinguish between patients with cervical node-negative and node-positive disease. Some patients both with and without cervical metastases who are long-term survivors had nuclear roundness scores in the highest range, reflecting greatest variation from normal.

Complications and early outcome of anterior craniofacial resection.

OBJECTIVE: To evaluate the complications of anterior craniofacial resection and correlate their impact with tumor control status. DESIGN: We conducted a retrospective review of 32 consecutive, operable patients' records seen over a 6-year period, requiring 35 procedures. SETTING: Academic tertiary referral medical center. PARTICIPANTS: Twenty-six patients (81%) had malignant lesions (esthesioneuroblastoma, squamous cell carcinoma, and a group of miscellaneous malignant tumors). Six patients had various benign neoplasms. INTERVENTION: The surgical approach involved bifrontal craniotomy coupled with lateral rhinotomy in 19 cases (61%), facial degloving in 10 cases (32%), a total rhinectomy in one case, and endoscopic sinusectomy without facial incision in two cases. OUTCOME MEASURE: Clinically noted complications and oncologic outcome. RESULTS: There was one avoidable perioperative death indirectly associated with the patient's procedure. Nine patients suffered significant intracranial neurological complications such as tension pneumocephalus and delayed epidural abscess. All of these complications were managed successfully. Of patients with malignant tumors, 13 (52%) are alive with no evidence of disease and one is alive with recurrence after a mean follow-up period of 28.9 months. The 10 patients who succumbed to disease had a mean postoperative survival of 22.9 months. CONCLUSIONS: In contrast to the perspective of only a decade ago, we conclude that craniofacial resection is a relatively safe, versatile, and effective procedure for surgical management of tumors involving the anterior skull base.

Management of hydrocephalus resulting from acoustic neuromas.

Patients with large acoustic neuromas may have secondary obstructive hydrocephalus and occasionally significant neurologic deficit develops. At the House Ear Clinic, we have managed patients with hydrocephalus by translabyrinthine tumor removal without preoperative ventriculoperitoneal shunting. Forty-three patients with documented hydrocephalus who underwent acoustic neuroma removal have been reviewed. Six patients had neurologic deficit resulting from raised intracranial pressure before surgery. In each of these six cases, the deficit resolved after tumor removed without requiring shunting. Two patients had had ventriculoperitoneal shunts inserted because of neurologic deficit before referral for tumor removal. Two other patients underwent postoperative shunting for neurologic deficit --one at 2 weeks and one at 2 years. Cerebral or cerebellar herniation was not noted in any case. Cerebrospinal fluid leak occurred in five patients (11.6%) and culture-positive meningitis in two patients (4.6%). We conclude that decompression by translabyrinthine tumor removal is a safe method of management for patients with hydrocephalus resulting from large acoustic tumors.

The contour electrode array: safety study and initial patient trials of a new perimodiolar design.

OBJECTIVE: The aim of these studies was to investigate the insertion properties and safety of a new intracochlear perimodiolar electrode array design (Contour). BACKGROUND: An electrode array positioned close to the neural elements could be expected to reduce stimulation thresholds and might potentially reduce channel interaction. METHODS: Two sequential studies were conducted. In study 1, the Contour electrode array was inserted in 12 human temporal bones. After cochlear surface preparation, the position of the array was noted and the basilar membrane was examined for insertion damage. On the basis of the outcome of this temporal bone study, study 2 investigated the Contour array, mounted on a Nucleus CI-24 M device and implanted in three adult patients. RESULTS: Study I showed that in 10 temporal bones, the Contour array was positioned close to the modiolus, and the basilar membrane was intact. In the two remaining bones, the arrays had pierced the basilar membrane and were positioned in the scala vestibuli apical to the penetration. Statistical analysis showed an equivalent probability of insertion-induced damage of the two array designs. In study 2, image analysis indicated that the Contour electrodes were positioned closer to the modiolus than the standard Nucleus straight array. Lower T and C levels, but higher impedance values, were recorded from electrodes close to the modiolus. Initial speech perception data showed that all patients gained useful open-set speech perception, two patients achieving scores of 100% on sentence material 3 months postoperatively. CONCLUSIONS: The temporal bone studies showed the Contour electrode array to be generally positioned closer to the modiolus than the standard Nucleus straight array, and to have an equivalent probability of causing insertion-induced damage.

Correction of conductive hearing loss in children.

The focus of this article is the diagnosis and surgical correction of conductive hearing loss in children without aural atresia, cholesteatoma, or otitis media with effusion. An overview of the incidence of congenital conductive hearing loss and the types of middle ear anomalies are provided. Techniques of surgical correction are described with respect to the types of ossicular and middle ear abnormalities encountered for both congenital and acquired conductive hearing loss, including otosclerosis.

Endoscopic transnasal intradural repair of anterior skull base cerebrospinal fluid fistulae.

UNLABELLED: This study presents the techniques and results of endoscopic diagnosis and repair of cerebrospinal fluid (CSF) fistulae involving the anterior skull base and paranasal sinuses. DESIGN: A retrospective cohort study of all consecutive patients undergoing endoscopic repair of anterior skull base CSF fistulae. SETTING: Tertiary referral institutions. MATERIALS AND METHODS: Fifty-two patients underwent endoscopic repair of CSF fistula. Thirteen cases were traumatic in origin, 11 spontaneous not associated with meningoencephalocele and 12 with meningoencephalocele. Eleven were iatrogenic and five associated with transphenoidal pituitary surgery, two acute and three delayed following radiotherapy. The average age of patients was 43 and the male to female ratio was 2:1. A variety of techniques were used to repair the dural defect. In the majority of cases placement of a fat plug on the intracranial surface of the dura was performed. RESULTS: Forty-seven of the 52 patients had successful primary endoscopic repair of the CSF fistula and skull base defect. Five patients required a repeat procedure due to early failure of the repair. After an average follow-up of 27 months no patient has had any recurrence of leak giving a primary closure success rate of 90% and secondary closure rate of 100%. CONCLUSIONS: The endoscopic transnasal approach for repair of anterior skull base CSF fistula is a reliable technique and is now the procedure of choice for patients presenting with this problem.

Current management of acoustic neuromas: review of surgical approaches and outcomes.

The management options for patients with acoustic neuromas is discussed with a review of 164 patients assessed and treated between 1994 and 1998. Twenty-one patients have neurofibromatosis type II. In 33 cases initial observation was undertaken with repeated imaging. Surgical removal of 122 tumours was performed in 121 patients. Eleven of these patients have NF2, of whom three underwent Auditory Brainstem Implantation. Hearing preservation tumour removal was attempted in 37 and was successful in 20 (54%). The middle cranial fossa approach was used in ten cases with 100% successful hearing preservation. The retrosigmoid approach was used in 27 cases with 36% successful hearing preservation. Non-hearing preservation tumour removal was performed in 85 cases where hearing was poor or the tumour measured more than 2 cm within the cerebellopontine angle. The translabyrinthine approach was used in 80 of these patients. Postoperative facial nerve outcome was dependent on tumour size. All 38 patients with tumours

A case of pneumocephalus secondary to VP shunt in a patient with acoustic neuroma.

Pneumocephalus is an uncommon complication of ventriculo-peritoneal (VP) shunts. We present a case of pneumocephalus secondary to a VP shunt in a patient with an acoustic neuroma. The site of the cerebrospinal fluid fistula was found to be into an extensive petrous apex air cell system due to tumour erosion of the internal auditory canal.

The bioavailability of Tamoplex (tamoxifen). Part 2. A single dose cross-over study in healthy male volunteers.

Tamoxifen and N-desmethyltamoxifen plasma concentrations were determined in a single dose cross-over study with Tamoplex and Nolvadex at the dose height of 40 mg in 18 healthy male volunteers with a wash-out period of at least 140 days. ANOVA, power analysis and novel bioequivalence tests on AUC, Cmax and tcmax, including a non-parametric one, demonstrated bioequivalence of Tamoplex and Nolvadex 10 mg tablets. The mean AUC ( +/- SD) values of tamoxifen after administration of Tamoplex or Nolvadex tablets were 1076 +/- 265 and 1131 +/- 301 h ng ml-1, respectively. ANOVA on the AUC values gave a p value of 0.450 with a power of 0.85 and a 95% confidence interval of 81.8-108.5% was obtained. The 0.8 power test showed a determined difference of 18.9%, whereas the actual difference was 4.9%. Interindividual and intraindividual variation was assessed. The pharmacokinetic data, well established for 34 hr, constitute a basis for further studies on tamoxifen distribution, elimination and metabolism.

The bioavailability of Tamoplex (tamoxifen). Part 1. A pilot study.

Tamoxifen and N-desmethyltamoxifen plasma concentrations were found to be similar after a first single dose and during two months therapy with Tamoplex or Nolvadex in groups of 6 and 8 patients, respectively. Single dose absorption results in 10 healthy male volunteers demonstrated bioequivalence of Tamoplex and Nolvadex 10 mg tablets. A large interindividual variation in tamoxifen absorption data was observed, probably related to the dominating metabolic clearance of tamoxifen.

MR imaging features of an intracochlear acoustic schwannoma.

We present a very unusual case of an acoustic neuroma involving the left cochlea and internal auditory canal of a 24-year-old man. Clinical suspicion was aroused when the patient presented with a left total sensorineural hearing loss and continuing vertigo. The diagnosis was made pre-operatively with MRI after initial CT scanning was normal. The tumour was removed via a transotic approach. This case report demonstrates the MRI features of an intracochlear schwannoma and emphasizes the importance of MRI in patients with significant auditory and clinical abnormalities with normal CT scans of the relevant region.

Laryngeal imaging by computerized tomography and magnetic resonance following radiation therapy: a need for caution.

For patients with laryngeal tumours, the use of computerized tomography (CT) or magnetic resonance imaging (MR) may facilitate accurate staging by the demonstration of cartilage invasion or tumour extension to areas such as the pre-epiglottic space. The role of imaging in the follow-up of patients after radiotherapy, however, has not been examined. A prospective study of 18 patients undergoing laryngectomy was performed. The results of pre-operative CT and MR imaging were correlated with the pathological findings from whole organ axial sections of the laryngeal specimens. In five patients (28 per cent) both CT and MR images were significantly impaired by movement artefact. In the eight patients without previous radiotherapy, seven had adequate quality imaging and both CT and MR accurately demonstrated the site, size and extent of laryngeal tumour. In eight of the ten patients following radiation therapy the presence of tumour was correctly identified, however there was a poor correlation between the imaging and pathological findings. Two patients had radionecrosis alone. Neither CT nor MR imaging could differentiate between radionecrosis and recurrent tumour.

The Guildford trace elements external quality assessment scheme.

An international external quality assessment scheme for trace elements in biological fluids is described. Programmes for aluminium, copper, zinc, selenium, gold, lead, cadmium and mercury in serum, blood, urine, dialysis fluids and water are included with others under development. Preparation of reports is described and assessments of performance based on proximity to assigned values, differences in results between duplicate measurements and recovery of added analyte are given. Performance standards have been introduced to stimulate improvements in the quality of results.