Prognostic factors in intraoperative facial nerve monitoring for acoustic neuroma

OBJECTIVES

To determine the predictive value of intraoperative threshold stimulus for facial nerve outcome and the prevalence and prognostic value of persistent trains of activity and frequent spontaneous or mechanically induced contractions during acoustic neuroma surgery.

STUDY DESIGN

Prospective recording and subsequent review of facial nerve activity.

SETTING

Tertiary referral centre.

PATIENTS AND METHODS

Consecutive patients undergoing acoustic neuroma surgery. Intraoperative facial nerve activity was digitised and stored on a personal computer for future analysis. Operative events were flagged. Recordings were available in 27 patients.

MAIN OUTCOME MEASURES

Frequent mechanically induced contractions (< 20), prolonged trains of facial nerve activity (total time > 199 seconds), and facial nerve brainstem stimulus threshold were correlated with facial nerve outcome.

RESULTS

A brainstem stimulus threshold > 0.1 mA was significantly associated with intermediate or poor facial nerve function (House-Brackmann grade > 2) on the sixth postoperative day, at 1 month and 6 months. Patients with normal or near-normal facial function on the first day and a threshold of > 0.1 mA were significantly more likely to develop a delayed facial nerve palsy. Frequent contractions were noted in 74% of patients and persistent train activity in 59%. Neither was predictive of facial nerve outcome.

CONCLUSIONS

An elevated brainstem threshold is helpful in predicting delayed facial nerve palsy and suboptimal facial nerve outcome. Persistent train activity and frequent contractions, do not have major prognostic significance.

HIV-1 dynamics after transient antiretroviral therapy: implications for pathogenesis and clinical management

Simple models of CD4 lymphocyte interactions with human immunodeficiency virus (HIV) lead to the hypothesis that progression of HIV infection involves an increase in viral replicative capacity, due either to changes in the virus or in the host environment, or both. In order to consider how changes in plasma virus load after transient, potent antiretroviral therapy can be used to test the above hypothesis--a simple mathematical model that encompasses the processes of (1) arrival of new CD4 lymphocytes, (2) death/removal of these cells by HIV-independent mechanisms, (3) infection of susceptible CD4 lymphocytes by HIV, and (4) death/removal of infected cells was investigated. This showed that the in vivo rate of increase in plasma virus load immediately after transient therapy provides a measure of the viral replicative capacity. Thus, the hypothesis that progression of HIV infection involves an increase in viral replicative capacity can be tested by measuring this viral growth rate in patients with high CD4 counts and in patients with low CD4 counts. Studies should thus investigate dynamics of changes in virus levels after stopping antiretroviral therapy and, in particular, measure rates of increase in virus in patients at high and low CD4 counts. In practice, such data may assist in therapeutic management of patients with HIV infection.

Comparative efficacy and potency of ipratropium via Turbuhaler and pressurized metered-dose inhaler in reversible airflow obstruction

Ipratropium bromide (IB), typically delivered by pressurized metered dose inhaler (pMDI), is used to treat patients with reversible airways obstruction. Use of the pMDI, unlike the Turbuhaler (TH), demands co-ordination of actuation with inspiration for efficient use. Two studies were carried out to compare the relative efficacy and potency of IB delivered by TH or pMDI. Both studies were of a randomized, double-blind and cross-over design. For the efficacy study, 15 patients received a cumulative dose of 160 microg IB via TH or pMDI as doses of 20, 20, 40 and 80 microg at 45 min intervals on two days. Forced expiratory volume in one second (FEV1) was measured prior to and 40 min after dosing. For the potency study, 33 patients received 10, 20 or 40 microg of IB via TH, 20 microg IB via pMDI, or placebo, on five days. FEV1 was recorded prior to and 15-360 min after dosing. For the efficacy study, there was no difference in FEV1 response to a cumulative dose of IB via pMDI and TH. More than 80% of the maximum effect was seen at the lowest dose (20 microg of IB). Regarding the potency study, the FEV1 response to 20 microg IB administered via pMDI was similar to that of 10 microg via TH; 20 microg via TH was significantly more effective than 20 microg via pMDI (p<0.05). In conclusion, the efficacy study showed that maximum FEV1 occurred at low doses of IB, negating any opportunity to identify differences between devices. The potency study indicated that the 10 microg dose via TH was of similar efficacy to the 20 microg dose via pMDI, confirming an efficacy ratio of 1.5-2.0:1 for the TH device.

Systemic corticosteriod rapidly reverses bronchodilator subsensitivity induced by formoterol in asthmatic patients

There is evidence that downregulation and desensitization of airway beta 2-adrenoceptors (beta 2-AR) develops after continuous exposure to long-acting beta 2-agonists such as formoterol and salmeterol. To investigate the facilitatory effects of acute administration of systemic corticosteroid on bronchodilator subsensitivity, as might occur in the setting of acute asthma, 12 subjects with moderately severe asthma, with a mean FEV1 of 66% predicted, of whom were all receiving inhaled corticosteriod, were randomized to receive either inhaled placebo (PL) or inhaled formoterol (FM) 24 micrograms twice daily for 4 wk in a double-blind crossover study. Subjects were also genotyped in terms of beta 2-Ar polymorphism at loci 16 and 27. A dose-response curve (DRC) and duration-time profile for FM (12 to 108 micrograms) was produced 1 h after administration of placebo tablets and after injection at 3 wk, and 1 h after administration of oral prednisolone, 50 mg, and intravenous hydrocortisone, 200 mg, at 4 wk. Comparisons between treatments were made with area-under-curve (AUC) measurements as the change from baseline. There was a significant rightward shift in the DRC after FM as opposed to placebo for delta FEV1 (as AUC, L.h): 2.51 versus 4.22 (95% CI: 0.54 to 2.89; p = 0.01) and delta FEF25-75 (as AUC, L x 10(3)): 11.30 versus 19.94 (95% CI: 2.12 to 15.12; p = 0.01). This was significantly reversed by steroid (S) for FEV1 (FM versus FM+5): 2.51 versus 3.57 (95% CI: 0.11 to 2.27; p = 0.03) and for FEF25-75: 11.30 versus 18.47 (95% CI: 2.52 to 11.70; p = 0.005). Lymphocyte beta 2-AR density (log Bmax; fmol/10(6) cells) showed significant upregulation 3 h after steroid (FM+5 versus FM): 0.34 versus 0.24 (95% CI: 0.02 to 0.18; p = 0.01). For heart-rate response (as AUC, beats), there was subsensitivity with FM versus PL: 2,700 versus 5,200 (95% CI: 40 to 5,000; p < 0.001), and this was reversed by steroid (FM+5 versus FM): 9,600 versus 2,700 (95% CI: 4,900 to 8,800; p < 0.001). This reversal by systemic corticosteroid appears to be generally independent of beta 2-AR polymorphism at loci 16 and 27. In conclusion, we have demonstrated that bronchodilator subsensitivity occurs after regular inhaled FM in asthmatic patients, and is rapidly reversed by systemic corticosteroid. Thus, in acute asthma, systemic corticosteroid should be administered a soon as possible, in order to restore normal airway beta 2-AR sensitivity, particularly in patients who are receiving regular long-acting beta 2-agonists.

Computed tomography in chronic inflammatory bowel disease

In children with complicated inflammatory bowel disease, conventional ultrasound imaging may not define the extent of extraluminal disease and the involvement of other viscera. Three children with chronic inflammatory bowel disease are presented, where computed tomography was well tolerated and provided valuable information on extraluminal disease, involvement of other organs, and the state of the bowel wall and mesentery. In children in whom ultrasound examination is inconclusive or limited by gas or tenderness, computed tomography can provide important information that may determine clinical management.

Correlation of peak systolic velocity and angiographic measurement of carotid stenosis revisited

BACKGROUND AND PURPOSE

Recent observations from the North American Symptomatic Carotid Endarterectomy Trial (NASCET) questioned the reliability of peak systolic velocity (PSV) criteria for grading carotid stenosis. We compared PSV and angiographic measurements at our center together with known physiological relationships to investigate the accuracy of ultrasound.

METHODS

Consecutive patients who underwent both color-coded duplex ultrasound and intra-arterial digital subtraction angiography were studied. PSV was determined with angle correction at the site of the tightest internal carotid artery narrowing. Carotid stenosis was measured on angiograms with the North American (N) and common carotid (C) methods. Variables for the stepwise multiple linear regression analysis were selected from an axisymmetrical flow model.

RESULTS

Eighty bifurcations were imaged in 40 patients. PSV did not exceed 140 cm/s in normal vessels. In diseased arteries, PSV increased proportionally with increasing stenosis and decreased to 0 cm/s at occlusion. In stepwise selection of polynomial terms, the linear, quadratic, and cubic correlations of .38, .17, and .22 for N and .45, .24, and .03 for C were found to be significant (P < .02). When only stenosed vessels were evaluated, PSV increase was found with greater scatter for the N measurement: r2 = .73 for N and r2 = .85 for C (n = 50; P = .03 for the difference between two correlated correlation coefficients).

CONCLUSIONS

At our laboratory PSV consistently correlates well with N and C angiographic measurements, as determined with a simple flow model. The complex nature of these correlations and greater variability of the N measurement should be taken into account when data from different centers are compared.

Comparative psychophysical evaluation in cochlear implantation: electrical and magnetic stimulation

Transtympanic electrical stimulation, either in the form of round window or promontory placement of electrode prior to cochlear implantation is an accepted and commonly used psychophysical tool. Certain response parameters have been identified as predictors of outcome. This study compared the subjective auditory responses generated by promontory electrical stimulation (PES) with those from two noninvasive modalities, namely peritympanic electrical stimulation (PTES) and transcranial magnetic stimulation (TMS). Ten postlingually deafened adult cochlear implant candidates were studied. Standard psychophysical parameters were obtained from patients undergoing PES and PTES. A more subjective form of evaluation was conducted for TMS. Subsequently, nine patients received the multichannel Nucleus (Cochlear Corp., Denver, CO, U.S.A.) implant and one patient a Clarion (Advanced Bionics, Sylmar, CA, U.S.A.) implant. Compared with PES. PTES elicited increased threshold responses with similar dynamic ranges between 50 and 400 Hz of stimulation. The differences were, by and large, insignificant. PTES appeared to be a useful alternative in selected individuals owing to its noninvasiveness. TMS, on the other hand, was incapable of clearly inducing auditory percepts. It also produced concomitant facial and trigeminal stimulation, limiting its potential use as a prognostic tool.

A locus for bipolar affective disorder on chromosome 4p

The main clinical feature of bipolar affective disorder is a change of mood to depression or elation. Unipolar disorder, also termed major depressive disorder, describes the occurrence of depression alone without episodes of elevated mood. Little is understood about the underlying causes of these common and severe illnesses which have estimated lifetime prevalences in the region of 0.8% for bipolar and 6% for unipolar disorder. Strong support for a genetic aetiology is found in the familial nature of the condition, the increased concordance of monozygotic over dizygotic twins and adoption studies showing increased rates of illness in children of affected parents. However, linkage studies have met with mixed success. An initial report of linkage on the short arm of chromosome 11 (ref. 4) was revised and remains unreplicated. Reports proposing cosegregation of genes found on the X chromosome with bipolar illness have not been supported by others. More recently bipolar disorder has been reported to be linked with markers on chromosomes 18, 21, 16 and a region on the X chromosome different from those previously suggested. We have carried out a linkage study in twelve bipolar families. In a single family a genome search employing 193 markers indicated linkage on chromosome 4p where the marker D4S394 generated a two-point lod score of 4.1 under a dominant model of inheritance. Three point analyses with neighbouring markers gave a maximum lod score of 4.8. Eleven other bipolar families were typed using D4S394 and in all families combined there was evidence of linkage with heterogeneity with a maximum two-point lod score of 4.1 (theta = 0, alpha = 0.35).

Peak inspiratory flow through Turbuhaler in acute asthma

Efficient use of dry powder inhalers, such as Turbuhaler, is dependent on the generation of adequate inspiratory flow. It is not clear whether patients with acute asthma are able to generate adequate flow. Peak inspiratory flow (PIF) was measured through an empty Turbuhaler, and without this device, in 99 adults presenting to hospital with acute exacerbations of asthma. Where possible, patients were studied prior to nebulized bronchodilator therapy. Mean (SD) forced expiratory volume in one second (FEV1) was 1.2 (0.7) L, forced vital capacity (FVC) 2.1(1.0) L and peak expiratory flow (PEF) 199 (92) L.min-1. PIF without Turbuhaler was 152 (77) L.min-1 and correlated with PEF (r = 0.69). PIF through Turbuhaler was 60 (20) L.min-1 and weakly correlated with PEF (r = 0.35), and with PIF without Turbuhaler (r = 0.43). Two patients failed to generate the minimum inspiratory flow (30 L.min) required for efficient use of Turbuhaler; both recorded 26 L.min-1. Acute asthma is associated with considerable inspiratory, as well as expiratory airflow limitation. The relationship between inspiratory and expiratory airflow is not strong enough to predict whether patients with severe acute asthma will have difficulty using dry powder inhalers efficiently. Despite this, 98% of patients in this study generated inspiratory flow through Turbuhaler which would allow a therapeutically active amount of bronchodilator drug to be delivered to the airways.

The evolution of the clinician-scientist model of neurological rehabilitation

Over the past three or four decades two treatment technologies have been evolving in parallel, recently to some extent merging. The first of these technologies is behaviour analysis, with its emphasis on identification and manipulation of variables external to the individual as controlling agents. The second is neurological rehabilitation, with a characteristic focus of resources on recovery of function following neurological damage. The histories of both of these technologies are similar in that they emerged from basic laboratory research with non-human subjects, followed by extension of findings to research with humans, culminating in widespread formal application of results. The past 5 years have seen a convergence of behaviour analytic and neurological rehabilitation techniques resulting in major shifts in treatment service delivery systems. We briefly chronicle the emergence of these two technologies from their basic underpinnings through world-wide use. Further, discussion is provided describing our and others' experience with the combining of behaviour and neurological rehabilitation. Finally, we give an account of an innovative neurological rehabilitation service delivery system designed to deliver effective cost-efficient treatment in the patient's natural environment. Implicit in the design and implementation of this real-world model of rehabilitation is the combination of behavioural technology and neurological rehabilitation towards the achievement of functional outcomes which endure. Our purpose in the above is to provide an introduction to present use and future potential of behaviour analytic methodologies and technologies in rehabilitation.

Clinical audit of a specialist symptomatic breast clinic

The efficient delivery of health care requires vigilant quality assurance. We describe the audit of our symptomatic breast clinic, which includes the option of a one-stop diagnostic service. A total of 134 new and 386 follow-up patients attended over four consecutive clinics. The majority of new referrals (68%) were seen by a consultant surgeon. Urgent referrals were seen significantly sooner than routine referrals (P < 0.001, chi 2-test), and the mean wait from designated appointment to seeing the surgeon was 37.6 (range-68 to 171) min. One-stop investigations were offered to 50 patients; of these, 36 women (72%) had a total wait of less than 2 h. For those not investigated at the same clinic, the mean time until investigations was 6.1 (range 0-36) days and mean recall was 2.7 (range 1-8) weeks. Patients undergoing definitive surgery for cancer (n = 5) were operated on average 14.2 (range 7-27) days after the decision was made in outpatients, while the mean waiting time for non-cancer operations was 49.7 (range 15-98) days. Objective audit on outpatient services is possible and can lead to improvement of services.

Tuberculous pancreatitis: a diagnostic problem. Case report and review of literature

A 22-year-old Pakistani man presented with a 1-year history of recurrent attacks of pancreatitis of unknown etiology that had required hospitalization and extensive investigation in Pakistan. He was admitted with abdominal pain, fever, and weight loss. An ultrasound and computed tomographic scan of the abdomen revealed abdominal lymphadenopathy, bulky and inhomogeneous pancreas, and a large fluid collection anterior to the right lobe of the liver. The collection was aspirated but Gram-stain, Ziehl-Neelsen stain for acid-fast bacilli, and DNA analysis by a highly specific polymerase chain reaction-based assay were negative. Because of a strong clinical suspicion of tuberculosis, the patient was started on antituberculous chemotherapy; 4 weeks later the aspirate grew Mycobacterium tuberculosis (hominis). The patient improved rapidly and has remained well after 18 months follow-up. A high index of clinical suspicion and appropriate microbiological investigation is required for the diagnosis of this rare, but potentially curable cause of pancreatitis.

Empowerment and the psychiatric consumer/ex-patient movement in the United States: contradictions, crisis and change

A political movement in the United States by consumers and ex-patients of psychiatry has challenged the assumptions and negative consequences of traditional mental health practice and its control by professionals. In recent years, the movement has succeeded in gaining support to produce alternative programs based on a philosophy of 'consumer empowerment' and run entirely by consumers and ex-patients. In this article, I present results from an ethnographic study of one such alternative and I attempt to explain the discrepancy between the center's philosophy of empowerment and its actual practices. Utilizing this data, the consumer literature, and interviews with consumer leaders nationwide, I explain this situation in terms of conceptual problems with the terms 'empowerment' and 'consumer empowerment', local structural conditions under which the center operated, and the larger situation of the psychiatric consumer/ex-patient movement in the United States today. The case study represents a crisis in the consumer movement today, in which rapid growth of alternatives has been accompanied by a social amnesia of the emancipatory vision that originally spawned the movement.

Post-operative serial prostate-specific antigen and transrectal ultrasound for staging incidental carcinoma of the prostate

OBJECTIVES

To examine the value of post-operative serum prostate-specific antigen (PSA), PSA density, incremental change in serial serum PSA (PSA slope) and transrectal ultrasound (TRUS) in the assessment of residual malignancy after the diagnosis of clinically unsuspected prostatic adenocarcinoma at transurethral resection of the prostate (TURP).

PATIENTS AND METHODS

Forty-eight untreated patients with incidental carcinoma of the prostate, demonstrated at TURP for a clinically benign gland, were evaluated post-operatively with serum PSA and TRUS with multiple systematic prostatic biopsies. Prostatic volume was determined from TRUS measurements and PSA density was defined as serum PSA divided by gland volume. Those patients who did not undergo further treatment were monitored with serial PSA levels, and PSA slope was calculated as the overall annual percentage increase in serum PSA.

RESULTS

Among 36 patients staged T1A (A1), 11 (31%) had histologically proven residual carcinoma, and five of the 12 patients (42%) with T1B (A2) disease had no residual disease on biopsy. Serum PSA levels following TURP were greater in those patients with residual disease than those without (P = 0.001), but at a cut-off of 4.0 ng/mL--providing a sensitivity of 89%--the specificity of PSA alone was 57%. PSA density had an 83% sensitivity and a 67% specificity with a cut-off of 0.15 ng/mL/cm3. TRUS had a sensitivity of 63% and a specificity of 52%. An incremental rise in PSA exceeding 20% per year in untreated patients gave a sensitivity of 90% and specificity of 79% for biopsy proven residual malignancy.

CONCLUSION

This study demonstrates the inaccuracy of staging incidental prostatic malignancy by TURP. Although the performance of PSA density is better than that of PSA alone, the reliability of both are limited by the lack of specificity, and TRUS imaging lacks both sensitivity and specificity. The PSA slope has sufficient sensitivity and specificity to distinguish reliably most patients with biopsy proven residual malignancy. Although ultrasound-guided systematic biopsies provide a means for confirming residual malignancy, they may not be indicated in all patients with incidental carcinoma: for such patients, PSA progression may provide a rational basis for subsequent treatment.

One-stop diagnosis for symptomatic breast disease

A consultant-led one-stop diagnostic service has been available at a busy symptomatic breast clinic each week at St Bartholomew's Hospital for 18 months. Women can be investigated appropriately using mammography, ultrasonography and cytology with immediate reporting. The aim is to achieve a diagnosis and management plan for each patient at the initial outpatient visit. A prospective audit of four consecutive clinics was undertaken to assess the impact of this service on clinical practice. Fifty patients out of 134 new and 386 follow-up clinic attenders had one-stop investigations. As a result of immediate reporting, 48 (96%) patients had a management decision made at the first outpatient visit, 9 (18%) were offered surgery, and 18 (36%) were discharged with a benign diagnosis and no dominant mass. Four symptomatic cancers were detected and evaluated on a one-stop basis, constituting 8% of the workload of this clinic. The mean wait from designated appointment until surgical consultation was 37.7 min (range -68-171 min) and that for investigation until subsequent clinical review was 56.9 min (range -4-191 min). Thirty-six (72%) one-stop patients had a total wait of less than 2 h and 95% were seen in under 3 h. It is felt that the one-stop clinic allows optimum patient management, minimises anxiety associated with symptomatic breast disease, and maximises utilisation of hospital outpatient resources.

Effect of energy conservation and joint protection education in rheumatoid arthritis

As there is relatively little information about the effectiveness of occupational therapy (OT) in RA a questionnaire was devised to assess whether patient knowledge and performance of joint protection manoeuvres improved following OT intervention and, if improved, whether this was sustained over 6 months. A photographic multiple choice questionnaire was devised covering major categories of activities of daily living. The study population consisted of 55 patients with RA attending a rheumatology clinic who had not previously had OT treatment. Patients had a single instruction/treatment session with an occupational therapist of 1-h duration. Prior to treatment the questionnaire was administered by an independent assessor who re-administered the questionnaire 1 month and 6 months after the OT session. Following treatment there was a significant increase in scores at 1 month compared with pre-treatment (P < 0.001). There was no significant change in score at 6 months compared with 1 month. Qualitative analysis of age and sex showed no significant effects. OT leads to sustained improvement in patient knowledge and probably performance of joint protection manoeuvres in RA.

High altitude dives in the Nepali Himalaya

British divers undertook no-stop decompression dives at altitudes of 15,700 and 16,000 ft (4,785 and 5,33 m) in the Everest region of the Nepali Himalaya. They performed 23 dives on oxygen and two on nitrox (60% N2:50% O2. The dives took place under ice in two lakes, Gokyo Tsho and Donag Tsho. The maximum depth achieved was 98 feet fresh water (29.32 msw), maximum duration was 39 min in water, 44 min on gas.

Oral physostigmine and impaired memory in adults with brain injury

The purpose of this study was to examine the effects of physostigmine, a cholinergic agonist, on memory loss after traumatic brain injury (TBI), as compared to placebo or scopolamine, a cholinergic antagonist, using a double-blind, placebo-controlled design. Each subject received each active drug and placebo. Neuropsychological measures (Wechsler Memory Scale I and II, Selective Reminding Test, Trail-Making Test, Parts A and B, Digit Symbol, and Memory Questionnaire) and measures of clinical balance were completed at baseline, after each drug phase, and at 1 month follow-up. Thirty-six subjects completed the study with results showing an improvement in memory scores in 44% of subjects (responders) while taking oral physostigmine. The most sensitive measure was the Selective Reminding Test, specifically Long-term Storage. The impact of drugs on standing balance as compared to placebo was improved standing time in the responders: (1) with physostigmine when standing tandem with eyes closed (p < 0.05), and (2) with scopolamine when standing on one foot with eyes closed (p < 0.05). Results support the potential benefit of cholinergic agonists on memory after TBI and the need for further research of possible clinical markers for the drug.