Electrocochleography triggered intervention successfully preserves residual hearing during cochlear implantation: Results of a randomised clinical trial

BACKGROUND

Preservation of natural hearing during cochlear implantation is associated with improved speech outcomes, however more than half of implant recipients lose this hearing. Real-time electrophysiological monitoring of cochlear output during implantation, made possible by recording electrocochleography using the electrodes on the cochlear implant, has shown promise in predicting hearing preservation. Sudden drops in the amplitude of the cochlear microphonic (CM) have been shown to predict more severe hearing losses. Here, we report on a randomized clinical trial investigating whether immediate surgical intervention triggered by these drops can save residual hearing.

METHODS

A single-blinded placebo-controlled trial of surgical intervention triggered when CM amplitude dropped by at least 30% of a prior maximum amplitude during cochlear implantation. Intraoperative electrocochleography was recorded in 60 adults implanted with Cochlear Ltd's Thin Straight Electrode, half randomly assigned to a control group and half to an interventional group. The surgical intervention was to withdraw the electrode in ½-mm steps to recover CM amplitude. The primary outcome was hearing preservation 3 months following implantation, with secondary outcomes of speech-in-noise reception thresholds by group or CM outcome, and depth of implantation.

RESULTS

Sixty patients were recruited; neither pre-operative audiometry nor speech reception thresholds were significantly different between groups. Post-operatively, hearing preservation was significantly better in the interventional group. This was the case in absolute difference (median of 30 dB for control, 20 dB for interventional, χ² = 6.2, p = .013), as well as for relative difference (medians of 66% for the control, 31% for the interventional, χ² = 5.9, p = .015). Speech-in-noise reception thresholds were significantly better in patients with no CM drop at any point during insertion compared with patients with a CM drop; however, those with successfully recovered CMs after an initial drop were not significantly different (median gain required for speech reception score of 50% above noise of 6.9 dB for no drop, 8.6 for recovered CM, and 9.8 for CM drop, χ² = 6.8, p = .032). Angular insertion depth was not significantly different between control and interventional groups.

CONCLUSIONS

This is the first demonstration that surgical intervention in response to intraoperative hearing monitoring can save residual hearing during cochlear implantation.

Unilateral Cochlear Implants for Severe, Profound, or Moderate Sloping to Profound Bilateral Sensorineural Hearing Loss: A Systematic Review and Consensus Statements

Importance

Cochlear implants are a treatment option for individuals with severe, profound, or moderate sloping to profound bilateral sensorineural hearing loss (SNHL) who receive little or no benefit from hearing aids; however, cochlear implantation in adults is still not routine.

Objective

To develop consensus statements regarding the use of unilateral cochlear implants in adults with severe, profound, or moderate sloping to profound bilateral SNHL.

Design, Setting, and Participants

This study was a modified Delphi consensus process that was informed by a systematic review of the literature and clinical expertise. Searches were conducted in the following databases: (1) MEDLINE In-Process & Other Non-Indexed Citations and Ovid MEDLINE, (2) Embase, and (3) the Cochrane Library. Consensus statements on cochlear implantation were developed using the evidence identified. This consensus process was relevant for the use of unilateral cochlear implantation in adults with severe, profound, or moderate sloping to profound bilateral SNHL. The literature searches were conducted on July 18, 2018, and the 3-step Delphi consensus method took place over the subsequent 9-month period up to March 30, 2019.

Main Outcomes and Measures

A Delphi consensus panel of 30 international specialists voted on consensus statements about cochlear implantation, informed by an SR of the literature and clinical expertise. This vote resulted in 20 evidence-based consensus statements that are in line with clinical experience. A modified 3-step Delphi consensus method was used to vote on and refine the consensus statements. This method consisted of 2 rounds of email questionnaires and a face-to-face meeting of panel members at the final round. All consensus statements were reviewed, discussed, and finalized at the face-to-face meeting.

Results

In total, 6492 articles were identified in the searches of the electronic databases. After removal of duplicate articles, 74 articles fulfilled all of the inclusion criteria and were used to create the 20 evidence-based consensus statements. These 20 consensus statements on the use of unilateral cochlear implantation in adults with SNHL were relevant to the following 7 key areas of interest: level of awareness of cochlear implantation (1 consensus statement); best practice clinical pathway from diagnosis to surgery (3 consensus statements); best practice guidelines for surgery (2 consensus statements); clinical effectiveness of cochlear implantation (4 consensus statements); factors associated with postimplantation outcomes (4 consensus statements); association between hearing loss and depression, cognition, and dementia (5 consensus statements); and cost implications of cochlear implantation (1 consensus statement).

Conclusions and Relevance

These consensus statements represent the first step toward the development of international guidelines on best practices for cochlear implantation in adults with SNHL. Further research to develop consensus statements for unilateral cochlear implantation in children, bilateral cochlear implantation, combined electric-acoustic stimulation, unilateral cochlear implantation for single-sided deafness, and asymmetrical hearing loss in children and adults may be beneficial for optimizing hearing and quality of life for these patients.

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.

First-in-human trial of a novel suprachoroidal retinal prosthesis

Retinal visual prostheses (“bionic eyes”) have the potential to restore vision to blind or profoundly vision-impaired patients. The medical bionic technology used to design, manufacture and implant such prostheses is still in its relative infancy, with various technologies and surgical approaches being evaluated. We hypothesised that a suprachoroidal implant location (between the sclera and choroid of the eye) would provide significant surgical and safety benefits for patients, allowing them to maintain preoperative residual vision as well as gaining prosthetic vision input from the device. This report details the first-in-human Phase 1 trial to investigate the use of retinal implants in the suprachoroidal space in three human subjects with end-stage retinitis pigmentosa. The success of the suprachoroidal surgical approach and its associated safety benefits, coupled with twelve-month post-operative efficacy data, holds promise for the field of vision restoration.

Trial Registration

Clinicaltrials.gov NCT01603576

Method transfer, partial validation, and cross validation: recommendations for best practices and harmonization from the global bioanalysis consortium harmonization team

This paper presents the recommendations of the Global Bioanalytical Consortium Harmonization Team on method transfer, partial validation, and cross validation. These aspects of bioanalytical method validation, while important, have received little detailed attention in recent years. The team has attempted to define, separate, and describe these related activities, and present practical guidance in how to apply these techniques.

Surgical implications of perimodiolar cochlear implant electrode design: avoiding intracochlear damage and scala vestibuli insertion

OBJECTIVE

To review the mechanisms and nature of intracochlear damage associated with cochlear implant electrode array insertion, in particular, the various perimodiolar electrode designs. Make recommendations regarding surgical techniques for the Nucleus Contour electrode to ensure correct position and minimal insertion trauma.

BACKGROUND

The potential advantages of increased modiolar proximity of intracochlear multichannel electrode arrays are a reduction in stimulation thresholds, an increase in dynamic range and more localized neural excitation. This may improve speech perception and reduce power consumption. These advantages may be negated if increased intracochlear damage results from the method used to position the electrodes close to the modiolus.

METHOD

A review of the University of Melbourne Department of Otolaryngology experience with temporal bone safety studies using the Nucleus standard straight electrode array and a variety of perimodiolar electrode array designs; comparison with temporal bone insertion studies from other centres and postmortem histopathology studies reported in the literature. Review of our initial clinical experience using the Nucleus Contour electrode array.

RESULTS

The nature of intracochlear damage resulting from electrode insertion trauma ranges from minor, localized, spiral ligament tear to diffuse organ of Corti disruption and osseous spiral lamina fracture. The type of damage depends on the mechanical characteristics of the electrode array, the stiffness, curvature and size of the electrode in relation to the scala, and the surgical technique. The narrow, flexible, straight arrays are the least traumatic. Pre-curved or stiffer arrays are associated with an incidence of basilar membrane perforation. The cochleostomy must be correctly sited in relation to the round window to ensure scala tympani insertion. A cochleostomy anterior to the round window rather than inferior may lead to scala media or scala vestibuli insertion.

CONCLUSION

Proximity of electrodes to the modiolus can be achieved without intracochlear damage provided the electrode array is a free fit within the scala, of appropriate size and shape, and accurate scala tympani insertion is performed.

12-Month Post-Operative Results for Older Children Using Sequential Bilateral Implants

Within a long-term project investigating the perceptual benefits of bilateral implants, six children aged 5 to 15 yr received a second implant. Parent reports of functional performance were collected, and localization and spondee discrimination in noise was assessed. Outcomes varied from no benefit to significant benefit, although no improvement in localization was demonstrated. A major proportion of the benefit was likely due to headshadow effect. Success did not correlate with hearing aid use, age, time between implants, or second implant experience.

Multichannel auditory brainstem implantation: the Australian experience

The multichannel auditory brainstem implant (ABI) provides the potential for hearing restoration in patients with neurofibromatosis type 2 (NF2). Programmes for auditory brainstem implantation have been established in two Australian centres. Eight patients have been implanted under the protocol of an international multi-centre clinical trial. Three patients had ABI insertion at the time of first side tumour removal, four at second side tumour removal and one after previous bilateral surgery where there was some residual tumour. The translabyrinthine approach was used in all cases. Successful positioning of the electrode array was achieved in seven of eight patients, all of whom achieved auditory perception with electrical stimulation. Intra-operative electrically evoked auditory brainstem response testing was successful in four patients and was useful in confirming correct electrode position. In six cases post-operative psychophysical and auditory perception testing demonstrated that useful auditory sensations were achieved. Five of these patients regularly used the implant. In one patient electrode placement was unsuccessful and only non-auditory sensations occurred on stimulation. In the remaining patients non-auditory sensations were minimal and avoidable by selective electrode programming. Auditory brainstem implantation should be considered in patients with NF2. The greatest benefit is seen in patients without debilitating disease who have non-aidable hearing in the contralateral ear.

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.

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 </= 1.5 cm have normal (Grade 1) facial function. For all sized tumours, 90% of patients have good facial function (82% Grade 1, 8% Grade 2), 7% of patients have moderate function (6% Grade 3 and 1% Grade 4) and only 3% of patients have poor function (2% Grade 5, 1% Grade 6). Lasting complications were minimal with no operative mortality and eight patients (6.4%) suffering CSF fistulae. Seven patients in this series have had stereotactic radiation with variable outcome. The radiobiology of both single dose and fractionated stereotactic radiation is described and the current role of stereotactic radiation in the management of acoustic neuromas is discussed. Surgical tumour removal by an experienced multi-disciplinary team remains the primary treatment modality for acoustic neuromas. The middle cranial fossa approach is recommended for management of intracanalicular tumours. The translabyrinthine approach facilitates facial nerve preservation, particularly in patients with large tumours.

Susac syndrome: microangiopathy of the retina, cochlea and brain

BACKGROUND

Susac syndrome is characterized by the triad of branch retinal arterial occlusions, encephalopathy and cochlear microangiopathy. The underlying process is believed to be a small vessel vasculitis causing microinfarcts in the retina, brain and cochlea.

METHODS

Analysis of two male and two female cases of Susac syndrome recognized in Australia.

RESULTS

In this series the epidemiology, mode of presentation, ophthalmologic features, neurologic and cochleo-vestibular features, radiologic characteristics, cerebrospinal fluid findings, therapeutic interventions, clinical course and outcome of Susac syndrome is examined. Key ophthalmologic differential diagnoses include systemic lupus erythematosis (SLE), Behçet's syndrome and other vasculitides such as sarcoidosis, tuberculosis, syphilis and lymphoma. Neuro-otologic features are most frequently misdiagnosed as multiple sclerosis.

CONCLUSION

Susac syndrome, first described in 1979, is becoming an increasingly recognized condition. Early recognition of the syndrome is important because treatment with systemic immunosuppression may minimize permanent cognitive, audiologic and visual sequelae.

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.

Fourth branchial sinus causing recurrent cervical abscess

BACKGROUND

Three patients who presented with recurrent cervical abscesses were found to have a branchial sinus arising in the piriform fossa. Each patient had previously had cervical abscess drainage procedures.

METHODS

A retrospective review of patients with recurrent cervical abscess and associated fourth branchial sinus was carried out.

RESULTS

In each case, imaging and endoscopy identified a sinus tract from the left piriform fossa. Neck exploration with hemithyroidectomy and excision of the sinus tract was performed without further recurrence of abscess.

CONCLUSIONS

We believe these cases to represent a fourth branchial sinus. The relevant embryology and anatomy of the branchial apparatus is discussed and the pathways for the sinus and fistulous tracts of branchial sinus origin are reviewed. Branchial sinuses are uncommon, but should be considered as the underlying aetiology in patients who present with recurrent cervical abscesses.

Skull osteomyelitis due to Salmonella species: two case reports and review

Osteomyelitis of the skull is a rare disease. We describe two cases due to Salmonella typhimurium and review 10 previously reported cases of salmonella osteomyelitis of the skull. This infection is frequently complicated by extradural abscess, which may be asymptomatic. Diagnostic imaging by means of computed tomographic scanning with contrast or gadolinium-enhanced magnetic resonance imaging should be performed to detect this complication. A good outcome can be expected with a combination of surgery and antibiotic therapy.

Otitis externa. Presentation and management

Otitis externa is a common condition presenting in both general and hospital practice. Diagnosis and treatment are usually straightforward; however appropriate management requires recognition of predisposing and precipitating factors, effective cleaning of the external auditory canal and administration of suitable topical or systemic medication or both. The aim of this article is to provide an overview of the clinical features and management of otitis externa with a discussion of the differential diagnosis.

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.

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.

Findings of an external quality assessment scheme for determining aluminum in dialysis fluids and water

The analytical performance of laboratories participating in the dialysis fluids and water aluminum program of the Guildford External Quality Assessment Scheme over the period 1986-1993 has been reviewed. For aluminum concentrations > 3.33 mumol/L in dialysis fluids, the between-laboratory CV has fallen from approximately 36% to 23%, whereas for specimens of water the reduction was from 36% to approximately 18%. Improvements at lower concentrations were less impressive. Performance of individual participants varied; only a few consistently provided accurate results. Many of the participants are able to measure serum aluminum well, so lack of expertise is not responsible for poor results. We suggest that matrix effects associated with different specimen types have a significant influence on performance and that due account is not always taken of these factors. Resolution of these problems would be aided by appropriate reference materials.

Findings of an external quality assessment scheme for determining aluminum in dialysis fluids and water

The analytical performance of laboratories participating in the dialysis fluids and water aluminum program of the Guildford External Quality Assessment Scheme over the period 1986-1993 has been reviewed. For aluminum concentrations &gt; 3.33 mumol/L in dialysis fluids, the between-laboratory CV has fallen from approximately 36% to 23%, whereas for specimens of water the reduction was from 36% to approximately 18%. Improvements at lower concentrations were less impressive. Performance of individual participants varied; only a few consistently provided accurate results. Many of the participants are able to measure serum aluminum well, so lack of expertise is not responsible for poor results. We suggest that matrix effects associated with different specimen types have a significant influence on performance and that due account is not always taken of these factors. Resolution of these problems would be aided by appropriate reference materials.

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.

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.

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.

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.

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.

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.

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.

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.