Gender disparities in patients undergoing extracorporeal cardiopulmonary resuscitation

Introduction

The use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) in extracorporeal cardiopulmonary resuscitation (eCPR) has emerged as a treatment option for selected patients who are experiencing refractory cardiac arrest (CA). In the light of increasing availability, the analyses of outcome-relevant predisposing characteristics are of growing importance. We evaluated the prognostic influence of gender in patients presenting with out-of-hospital cardiac arrest (OHCA) treated with eCPR.

Methods

We retrospectively analysed the data of 377 consecutive patients treated for OHCA using eCPR in our cardiac arrest centre from January 2016 to December 2022. The primary outcome was defined as the survival of patients until they were discharged from the hospital, with a favourable neurological outcome [cerebral performance category (CPC) score of ≤2]. Statistical analyses were performed using baseline comparison, survival analysis, and multivariable analyses.

Results

Out of the 377 patients included in the study, 69 (21%) were female. Female patients showed a lower prevalence rate of pre-existing coronary artery disease (48% vs. 75%, p < 0.001) and cardiomyopathy (17% vs. 34%, p = 0.01) compared with the male patients, while the mean age and prevalence rate of other cardiovascular risk factors were balanced. The primary reason for CA differed significantly (female: coronary event 45%, pulmonary embolism 23%, cardiogenic shock 17%; male: coronary event 70%, primary arrhythmia 10%, cardiogenic shock 10%; p = 0.001). The prevalence rate of witnessed collapse (97% vs. 86%; p = 0.016) and performance of bystander CPR (94% vs. 85%; p = 0.065) was higher in female patients. The mean time from collapse to the initiation of eCPR did not differ between the two groups (77 ± 39 min vs. 80 ± 37 min; p = 0.61). Overall, female patients showed a higher percentage of neurologically favourable survival (23% vs. 12%; p = 0.027) despite a higher prevalence of procedure-associated bleeding complications (33% vs. 16%, p = 0.002). The multivariable analysis identified a shorter total CPR duration (p = 0.001) and performance of bystander CPR (p = 0.03) to be associated with superior neurological outcomes. The bivariate analysis showed relevant interactions between gender and body mass index (BMI).

Conclusion

Our analysis suggests a significant survival benefit for female patients who obtain eCPR, possibly driven by a higher prevalence of witnessed collapse and bystander CPR. Interestingly, the impact of patient age and BMI on neurologically favourable outcome was higher in female patients than in male patients, warranting further investigation.

Prognostic influence of mechanical cardiopulmonary resuscitation on survival in patients with out-of-hospital cardiac arrest undergoing ECPR on VA-ECMO

Introduction

The use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) in extracorporeal cardiopulmonary resuscitation (ECPR) in selected patients after out-of-hospital cardiac arrest (OHCA) is an established method if return of spontaneous circulation cannot be achieved. Automated chest compression devices (ACCD) facilitate transportation of patients under ongoing CPR and might improve outcome. We thus sought to evaluate prognostic influence of mechanical CPR using ACCD in patients presenting with OHCA treated with ECPR including VA-ECMO.

Methods

We retrospectively analyzed data of 171 consecutive patients treated for OHCA using ECPR in our cardiac arrest center from the years 2016 to 2022. A Cox proportional hazards model was used to identify characteristics related with survival.

Results

Of the 171 analyzed patients (84% male, mean age 56 years), 12% survived the initial hospitalization with favorable neurological outcome. The primary reason for OHCA was an acute coronary event (72%) followed by primary arrhythmia (9%) and non-ischemic cardiogenic shock (6.7%). In most cases, the collapse was witnessed (83%) and bystander CPR was performed (83%). The median time from collapse to VA-ECMO was 81 min (Q1: 69 min, Q3: 98 min). No survival benefit was seen for patients resuscitated using ACCD. Patients in whom an ACCD was used presented with overall longer times from collapse to ECMO than those who were resuscitated manually [83 min (Q1: 70 min, Q3: 98 min) vs. 69 min (Q1: 57 min, Q3: 84 min), p = 0.004].

Conclusion

No overall survival benefit of the use of ACCD before ECPR is established was found, possibly due to longer overall CPR duration. This may arguably be because of the limited availability of ACCD in pre-clinical paramedic service at the time of observation. Increasing the availability of these devices might thus improve treatment of OHCA, presumably by providing efficient CPR during transportation and transfer.

Design and Calibration of Plane Mirror Setups for Mobile Robots with a 2D-Lidar

Lidar sensors are widely used for environmental perception on autonomous robot vehicles (ARV). The field of view (FOV) of Lidar sensors can be reshaped by positioning plane mirrors in their vicinity. Mirror setups can especially improve the FOV for ground detection of ARVs with 2D-Lidar sensors. This paper presents an overview of several geometric designs and their strengths for certain vehicle types. Additionally, a new and easy-to-implement calibration procedure for setups of 2D-Lidar sensors with mirrors is presented to determine precise mirror orientations and positions, using a single flat calibration object with a pre-aligned simple fiducial marker. Measurement data from a prototype vehicle with a 2D-Lidar with a 2 m range using this new calibration procedure are presented. We show that the calibrated mirror orientations are accurate to less than 0.6° in this short range, which is a significant improvement over the orientation angles taken directly from the CAD. The accuracy of the point cloud data improved, and no significant decrease in distance noise was introduced. We deduced general guidelines for successful calibration setups using our method. In conclusion, a 2D-Lidar sensor and two plane mirrors calibrated with this method are a cost-effective and accurate way for robot engineers to improve the environmental perception of ARVs.

Trigeminal endonasal perception - an outcome predictor for septoplasty

BACKGROUND

No adequate test exists to predict outcome after septoplasty. Despite adequate surgery, patients still might experience nasal breathing impairment. The aim of this study was to determine if pre-operative trigeminal sensitivity can predict satisfaction after septoplasty.

METHODS

Single centre prospective cohort study in tertiary referral centre with follow-up time of 6 weeks postoperatively. Patients scheduled for septoplasty or septorhinoplasty with turbinoplasty were consecutively selected the day before surgery. Standard preoperative examinations (acoustic rhinometry and Sniffin’ Sticks 12 test), the evaluation of nasal obstruction on a visual analogue scale (VAS) and the trigeminal lateralisation task were performed before and 6 weeks after surgery. Biopsies were taken during surgery and TRPV1 mRNA expression was measured by PCR.

RESULTS

Thirty patients were included with a median age of 29 years and equal gender distribution. Trigeminal perception and sensation of nasal obstruction showed a significant correlation: preoperative lateralisation test scores, representing endonasal trigeminal sensitivity, correlated significantly with the mean VAS change scores, which demonstrate subjective improvement. A lateralisation test score of 31.5 and more had a sensitivity of 88% to predict an improvement of more than 3 VAS points. Additionally, high TRPV1 mRNA expression was linked with good postoperative VAS scores.

CONCLUSION

The preoperative evaluation of the trigeminal sensitivity could improve patients’ selection for septoplasty with a higher rate of satisfaction. Endonasal trigeminal sensitivity is directly linked with subjective outcome. Therefore, patients with low trigeminal sensitivity should undergo septoplasty only after thorough counselling.

Outcome assessment in dermatology clinical trials and cochrane reviews: call for a dermatology-specific outcome taxonomy

BACKGROUND

Standardized outcome reporting is crucial for trial evidence synthesis and translation of findings into clinical decision-making. The OMERACT 2.0 Filter and COMET outcome domain taxonomy propose frameworks for consistent reporting of outcomes. There is an absence of a uniform dermatology-specific reporting strategy that uses precise and consistent outcome definitions.

OBJECTIVES

Our aim was to map efficacy/effectiveness outcomes assessed in dermatological trials to the OMERACT 2.0 Filter as a starting point for developing an outcome taxonomy in dermatology.

METHODS

We critically appraised 10 Cochrane Skin Reviews randomly selected from all 69 Cochrane Skin Reviews published until 01/2015 and the 220 trials included covering a broad spectrum of dermatological conditions and interventions. Efficacy/effectiveness outcomes were mapped to core areas and domains according to the OMERACT 2.0 Filter. The extracted trial outcomes were used for critical appraisal of outcome reporting in dermatology trials and for the preliminary development of a dermatology-specific outcome taxonomy.

RESULTS

The allocation of 1086 extracted efficacy/effectiveness outcomes to the OMERACT 2.0 Filter resulted in a hierarchically structured dermatology-specific outcome classification. In 506 outcomes (47%), the outcome concept to be measured was insufficiently described, hindering meaningful evidence synthesis. Although the core areas assessed in different dermatology trials of the same condition overlap considerably, quantitative evidence synthesis usually failed due to imprecise outcome definitions, non-comparable outcome measurement instruments, metrics and reporting.

CONCLUSIONS

We present an efficacy/effectiveness outcome classification as a starting point for a dermatology-specific taxonomy to provide trialists and reviewers with the opportunity to better synthesize and compare evidence.

The diagnostic test accuracy of rectal examination for prostate cancer diagnosis in symptomatic patients: a systematic review

Background

Prostate cancer is the most common cancer in men in the UK. NICE guidelines on recognition and referral of suspected cancer, recommend performing digital rectal examination (DRE) on patients with urinary symptoms and urgently referring if the prostate feels malignant. However, this is based on the results of one case control study, so it is not known if DRE performed in primary care is an accurate method of detecting prostate cancer.

Methods

The aim of this review is to ascertain the sensitivity, specificity, positive and negative predictive value of DRE for the detection of prostate cancer in symptomatic patients in primary care.

CENTRAL, MEDLINE, EMBASE and CINAHL databases were searched in august 2015 for studies in which a DRE was performed in primary care on symptomatic patients and compared against a reference diagnostic procedure.

Results

Four studies were included with a total of 3225 patients. The sensitivity and specificity for DRE as a predictor of prostate cancer in symptomatic patients was 28.6 and 90.7%, respectively. The positive and negative predictive values were 42.3 and 84.2%, respectively.

Conclusion

This review found that DRE performed in general practice is accurate, and supports the UK NICE guidelines that patients with a malignant prostate on examination are referred urgently for suspected prostate cancer. Abnormal DRE carried a 42.3% chance of malignancy, above the 3% risk threshold which NICE guidance suggests warrants an urgent referral. However this review questions the benefit of performing a DRE in primary care in the first instance, suggesting that a patient’s risk of prostate cancer based on symptoms alone would warrant urgent referral even if the DRE feels normal.

Differences in symptom expression between Vietnamese and German patients utilizing a psychiatric outpatient service using the PHQ

Objective

Despite a large body of work on somatic symptom presentation among people of Asian descent, research has shown heterogeneous results. Examining symptom presentation in clinically and ethnically well-characterized populations constitutes a first step towards better understanding differing patterns symptom of presentation. This is the first larger study aiming to compare Vietnamese and German psychiatric outpatients regarding symptom presentation.

Methods

110 Vietnamese and 109 German patients seeking psychiatric treatment at two outpatient clinic services in Berlin were asked to complete the patient health questionnaire (PHQ). Comparisons of Vietnamese and German patients were conducted using independent t-tests. The somatic symptom module (PHQ-15), the depression module (PHQ-9) and the original PHQ-modules examining anxiety and psychosocial stress levels were compared for both groups using multivariate analysis. Categorical variables were evaluated using Chi2 analysis. Crohnbach's alpha was calculated separately for both groups and all PHQ modules.

Results

Vietnamese patients endorsed significantly higher levels of somatic symptoms overall and on individual somatic items, such as pain-related disturbancies. Yet, German and Vietnamese patients did not differ in terms of depression severity. Vietnamese patients with fewer German language skills showed a significantly higher tendency for somatization. While German patients showed higher total scores on the anxiety- and stress-modules of the PHQ, this difference was not statistically significant. Vietnamese and German patients showed comparable Crohnbach's alpha for all subscales.

Conclusion

As data was collected from both groups upon the first visit to an outpatient clinic, the symptoms reported could be reflective of culture related symptom awareness when feeling discomfort in the context of mental illness.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

S2k guideline for treatment of cutaneous lupus erythematosus - guided by the European Dermatology Forum (EDF) in cooperation with the European Academy of Dermatology and Venereology (EADV)

Cutaneous lupus erythematosus (CLE) is a rare inflammatory autoimmune disease with heterogeneous clinical manifestations. To date, no therapeutic agents have been licensed specifically for patients with this disease entity, and topical and systemic drugs are mostly used 'off-label'. The aim of the present guideline was to achieve a broad consensus on treatment strategies for patients with CLE by a European subcommittee, guided by the European Dermatology Forum (EDF) and supported by the European Academy of Dermatology and Venereology (EADV). In total, 16 European participants were included in this project and agreed on all recommendations. Topical corticosteroids remain the mainstay of treatment for localized CLE, and further topical agents, such as calcineurin inhibitors, are listed as alternative first-line or second-line topical therapeutic option. Antimalarials are recommended as first-line and long-term systemic treatment in all CLE patients with severe and/or widespread skin lesions, particularly in patients with a high risk of scarring and/or the development of systemic disease. In addition to antimalarials, systemic corticosteroids are recommended as first-line treatment in highly active and/or severe CLE. Second- and third-line systemic treatments include methotrexate, retinoids, dapsone and mycophenolate mofetil or mycophenolate acid, respectively. Thalidomide should only be used in selected therapy-refractory CLE patients, preferably in addition to antimalarials. Several new therapeutic options, such as B-cell- or interferon α-targeted agents, need to be further evaluated in clinical trials to assess their efficacy and safety in the treatment of patients with CLE.

Evaluating the Impact of Performance Improvement Initiatives on Transplant Center Reporting Compliance and Patient Follow-Up After Living Kidney Donation

With the changing demographics of the living donor population and increased regulatory oversight, it is important that transplant centers report outcomes accurately. The aim of our retrospective cohort study of 312 living donors who underwent nephrectomy between 2008 and 2013 was to evaluate the impact of living donor program performance improvement initiatives on: (i) transplant center program reporting compliance; (ii) patient compliance with postdonation follow-up and its associated factors; and (iii) overall financial costs to the transplant center. The effect of the initiatives (donation eras 2008-2010 and 2011-2013) on compliance at key reporting points (6 months, 1 year, 2 years) was analyzed using correlation coefficients, χ(2) and Fisher's exact tests. Multivariable logistic regression models tested the initiatives' effect on the likelihood of patient follow-up. The initiatives were associated with significant improvement in form reporting compliance (r ≥ 0.862, p ≤ 0.027; 1 and 2 year Fisher's Exact p ≤ 0.002) and patient follow-up (χ(2) p ≤ 0.009) with acceptable transplant center costs. Multivariable analyses demonstrated that donation era was consistently and significantly (p < 0.001) associated with increased likelihood of postdonation patient follow-up. Institution of performance improvement initiatives with dedicated program resources is financially feasible and leads to more accurate and complete form reporting and improved patient follow-up after nephrectomy.

[Obstructive sleep apnea syndrome in children--status quo of diagnostics and treatment]

BACKGROUND AND METHODS

In the diagnostics and treatment of obstructive sleep apnea syndrome (OSAS), established standards for adults cannot be conferred on children. To get an overview concerning the code of practice, we questioned sleep laboratories performing polysomnographies in children about the used techniques, the interpretation of the results and the recommended therapy of OSAS in children.

RESULTS

17 sleep laboratories participated in the study. It became evident that the individual German sleep laboratories use different criteria in the diagnostics of OSAS in children. For treating OSAS in children, surgery by an ENT specialist is recommended in most cases (75%).

CONCLUSIONS

To enhance national and international comparability of diagnostic findings, adoption of the recommendations of the American Academy of Sleep Medicine (AASM) of 2007 for polysomnographic procedures and scoring is suggested.

[S1 guideline on the "diagnosis and treatment of snoring in adults"]

Due to the frequency of this phenomenon and the often considerable distress caused to the affected person, competent advice, diagnosis and treatment of snoring in adults is of particular importance. The aim of this guideline is to promote high-quality medical care for patients affected by this problem. According to the three-level concept of the AWMF, it corresponds to an S1 guideline. Prior to any therapeutic intervention, relevant sleep medical history, clinical examination, as well as a mandatory objective diagnostic measure are performed. Snoring is only treated if the patient asks for it. In general, invasive methods should be viewed critically and the patient should be advised correspondingly. In the case of surgical therapy, minimally invasive techniques are preferred. Reducing body weight (in the case of overweight snorers), abstinence from alcohol, nicotine and sleep medication, as well as maintaining a healthy sleep-wake cycle can be recommended from a sleep-medicine perspective, although convincing clinical studies are not yet available. Since evidence for the effectiveness of muscle stimulation or various methods for toning and training of the muscles of the floor of mouth is not available, these methods are not recommended. Snoring can be successfully treated with the use of an intraoral device; however, careful patient selection is important. Avoiding a supine position during sleep can be helpful in some cases. Only limited data is available on the success rates of the surgical approaches and long term data is often lacking, and not all techniques have been sufficiently evaluated from a scientific point of view. Nasal surgery is only indicated if the patient suffers from nasal obstruction. Extensive data supports the effectiveness of laser-assisted resection of excessive soft palate tissue (laser-assisted uvuloplasty, LAUP). In principle, however, such resections can be performed using other techniques. Placebo-controlled studies were able to prove the effectiveness of radiofrequency surgery of the soft palate. A reduction in snoring could also be achieved in many cases by means of soft palate implants with minimal post-operative morbidity. The indication for tonsillectomy and uvulopalatopharyngoplasty should be made cautiously due to the comparatively high morbidity associated with these procedures.

Rapid eye movement sleep deprivation decreases long-term potentiation stability and affects some glutamatergic signaling proteins during hippocampal development

Development of the mammalian CNS requires formation and stabilization of neuronal circuits and synaptic connections. Sensory stimulation provided by the environment orchestrates neuronal circuit formation in the waking state. Endogenous sources of activation are also implicated in these processes. Accordingly we hypothesized that sleep, especially rapid eye movement sleep (REMS), the stage characterized by high neuronal activity that is more prominent in development than adulthood, provides endogenous stimulation, which, like sensory input, helps to stabilize and refine neuronal circuits during CNS development. Young (Y: postnatal day (PN) 16) and adolescent (A: PN44) rats were rapid eye movement sleep-deprived (REMSD) by gentle cage-shaking for only 4 h on 3 consecutive days (total 12 h). The effect of REMS deprivation in Y and A rats was tested 3-7 days after the last deprivation session (Y, PN21-25; A, PN49-53) and was compared with younger (immature, I, PN9-12) untreated, age-matched, treated and normal control groups. REMS deprivation negatively affected the stability of long-term potentiation (LTP) in Y but not A animals. LTP instability in Y-REMSD animals was similar to the instability in even the more immature, untreated animals. Utilizing immunoblots, we identified changes in molecular components of glutamatergic synapses known to participate in mechanisms of synaptic refinement and plasticity. Overall, N-methyl-d-aspartate receptor subunit 2B (NR2B), N-methyl-d-aspartate receptor subunit 2A, AMPA receptor subunit 1 (GluR1), postsynaptic density protein 95 (PSD-95), and calcium/calmodulin kinase II tended to be lower in Y REMSD animals (NR2B, GluR1 and PSD-95 were significantly lower) compared with controls, an effect not present in the A animals. Taken together, these data indicate that early-life REMS deprivation reduces stability of hippocampal neuronal circuits, possibly by hindering expression of mature glutamatergic synaptic components. The findings support a role for REMS in the maturation of hippocampal neuronal circuits.

Einsatz der ösophagopharyngealen Druckmessung zur Topodiagnostik des Schnarchens

BACKGROUND

Depending on age and gender up to 60 % of the population snore regularly. As simple snoring is more a social than a medical problem, unlike OSAS, CPAP-therapy or multilevel surgery are not appropriate therapies for snoring. But alternative therapies, such as laser-assisted uvulopalatoplasty (LAUP) or uvulopalatopharyngoplasty (UPPP) address distinct sites of the pharynx. Therefore a correct identification of the snoring-source should optimise the selection of patients and improve the outcome of therapy. As there is no commonly recommended tool for identifying the snoring-source, the use of a new technique, based on pharyngeal pressure measurement, was tested.

METHODS

25 patients with suspected OSAS had standard polysomnography recordings during two nights with esophagopharyngeal pressure measurement on the second night. The pressure probe had 5 pharyngeal and 1 esophageal transducers. The curves of the pharyngeal pressure were examined for quick pressure changes superimposed on the slow pressure-changes caused by breathing. The appearance of these quick pressure changes was documented for each transducer throughout the whole night.

RESULTS

The average (+/- SD) Apnea-Hypopnea-Index in the patients was 28.3 +/- 24.8. 17 patients (68 %) had an AHI of more than 10. All patients showed heavy snoring. 23 patients (92 %) showed a high frequency, sawtooth-pattern, superimposed on the slow breathing rhythm in at least one channel and in association with snoring. 91 % of the patients showed a sawtooth pattern in more than one channel, but the pattern was always more pronounced in one channel compared to others. The sawtooth-pattern of the highest amplitude was seen in the pressure curves from the velum in 56 % of the patients, from the tonsils in 24 %, and from the tonguebase in 12 % of the patients.

CONCLUSIONS

Quick pressure changes from distinctive pharyngeal pressure transducers during snoring are common in OSAS patients and may indicate the source of snoring. Further investigations have to show whether this assumption is correct, and whether the quick pressure changes are also apparent in simple snorers.

[Snoring: therapeutic options]

Primary snoring is mainly the bed partner's problem and not that of the snorer. The request for treatment arises from how annoying the snoring is and how sensitive the bed partner is to noise. In addition to a thorough medical history and an ENT examination, a polysomnography should be always performed to differentiate between primary snoring, upper airway resistance and obstructive sleep apnoea syndromes. Primarily weight loss and avoidance of alcohol in the evening as well as devices and surgery are used in the treatment of snoring.

[Respiratory sleep disorders: benefit from laser-surgery]

Laser-assisted surgery is a valid option for the treatment of respiratory sleep disorders and complements established therapies. Laser-surgery of the inferior turbinates can improve nasal obstruction and amend or eliminate primary snoring. LAUP is as well an ambulant therapeutic method for snoring, but it is leading to strong post-operative pain and should exclusively be applied to patients with small tonsils or who already underwent tonsillectomy. OSAS can be worsened by LAUP and should therefore be excluded before the operation. In childhood OSAS laser tonsillotomy leads to a distinct improvement of sleep-disordered breathing with normalisation of the sleeping profile; it is less painful than tonsillectomy and a part of the tonsil is left to continue to exercise its function in the immune system.

Allergic rhinitis does not constitute a risk factor for obstructive sleep apnea syndrome

Obstructive sleep apnea syndrome (OSAS) is a condition characterized by recurrent episodes of obstruction of the upper airway. The aim of this study was to evaluate whether nasal obstruction due to allergic rhinitis constitutes a risk factor for OSAS. Patients (n = 119) presenting typical symptoms of sleep apnea were tested for OSAS using polysomnography. Additionally all patients were tested in vivo and in vitro (including nasal eosinophilic cationic protein) for allergic rhinitis. Examination for allergic rhinitis revealed that 88.3% of all patients had no allergic rhinitis, whereas only 11.7% were diagnosed as allergic. No significant differences in sleeping parameters were observed between allergic and non-allergic patients. Comparison of parameters indicative of relevant OSAS (apnea-hypopnea index [AHI] > 10) revealed that 60% of non-allergic patients had relevant OSAS, compared to only 50% of allergic patients. Investigation of allergic subgroups revealed similar results: no significant differences in sleeping parameters or elevated rates of relevant OSAS parameters were observed, especially in perennial allergic rhinitis due to house dust mites. No elevated rates of allergic rhinitis were observed in the studied cohort of patients suffering from sleep apnea or OSAS. Furthermore, no significant differences in sleeping behavior or polysomnography parameters were found on comparing allergic and non-allergic patients. In summary, our data rule out allergic rhinitis as a major risk factor for OSAS.

[Obstructive sleep apnea syndrome. Which therapy for which patients]

Obstructive sleep apnea syndrome is defined by the American Academy of Sleep Medicine as a combination of at least five obstructive events per hour of sleep and such other symptoms as daytime sleepiness, ischemic heart disease and stroke. In addition to weight reduction, the use of oral appliances, and continuous positive airway pressure (CPAP), a number of surgical interventions such as uvulopalatopharyngoplasty and maxillomandibular advancement are also available for the treatment of sleep apnea. Since no prolongation of life has yet been shown for most of the therapeutic options, treatment needs to be individualized on the basis of symptoms, clinical findings and compliance.

Analysis of the blind Drosophila mutant ninaB identifies the gene encoding the key enzyme for vitamin A formation invivo

Visual pigments (rhodopsins) are composed of a chromophore (vitamin A derivative) bound to a protein moiety embedded in the retinal membranes. Animals cannot synthesize the visual chromophore de novo but rely on the uptake of carotenoids, from which vitamin A is formed enzymatically by oxidative cleavage. Despite its importance, the enzyme catalyzing the key step in vitamin A formation resisted molecular analyses until recently, when the successful cloning of a cDNA encoding an enzyme with beta,beta-carotene-15,15'-dioxygenase activity from Drosophila was reported. To prove its identity with the key enzyme for vitamin A formation in vivo, we analyzed the blind Drosophila mutant ninaB. In two independent ninaB alleles, we found mutations in the gene encoding the beta,beta-carotene-15,15'-dioxygenase. These mutations lead to a defect in vitamin A formation and are responsible for blindness of these flies.

Relapsing polychondritis: a course over 20 years with cerebral involvement

Relapsing polychondritis is a chronic inflammatory disease associated with an autoimmune disorder in cartilaginous tissue, eyes, labyrinth, blood vessels, and central nervous system. We describe a 75-year-old woman who presented with a 20-year history of dyspnea, inspiratory stridor, and polyarthritis. She developed dysmorphism of both ears and a saddle nose approximately 10 years earlier. Subsequently, she suffered from hearing loss and a tremor. A T2-weighted magnetic resonance imaging scan of the brain revealed multiple, spotted signal intensities. Immunohistochemical analysis of a serum sample showed antibodies to cartilaginous tissue, which were further identified on immunoblotting as antibodies to type II collagen. The extremely prolonged course of disease (>20 years) until a correct diagnosis was made is remarkable. Also, cerebral involvement, which was most likely caused by cerebral angiitis, and which, to our knowledge, has never previously been reported in this form, was detected. Arch Otolaryngol Head Neck Surg. 2000;126:1495-1498

Multiply scattered light tomography and confocal imaging: detecting neovascularization in age-related macular degeneration

A novel technique, Multiply Scattered Light Tomography (MSLT), and confocal Infrared Imaging are used to provide diagnostic information using a comfortable, rapid, and noninvasive method. We investigated these techniques in detecting neovascularization in age-related macular degeneration. The MSLT used a Vertical Cavity Surface Emitting Laser (VCSEL) at 850 nm, while the confocal imaging technique used either the VCSEL or a 790 nm laser diode. Both were implemented into the topographical scanning system (TopSS, Laser Diagnostic Technologies, Inc.) Confocal imaging with both lasers provided different information about neovascularization as a function of focal plane, and different also from MSLT.

[Influence of nasal obstruction on sleep-associated breathing disorders]

BACKGROUND

The influence of nasal obstruction on sleep associated breathing disorders (SABD) and the controversial effects of surgical treatment are discussed.

RESULTS

Complete nasal obstruction caused by nasal packing increases SABD, but varies from patient to patient and depends on age and individual anatomy. Especially patients with preexisting obstructive sleep apnea syndrome (OSAS) can develop severe complications. Some authors found a higher frequency of SABD in patients with nasal obstruction due to anatomical alterations, i.e. septal deviation, while others denied this connection. Major causes for the development of SABD in nasal obstruction include certain reflex mechanisms, increased negative inspiration pressure with a tendency for pharyngeal collapse, and transition to transoral breathing. Intermittent dilatation of the nasal valve using stents or tapes will lead to a decrease of nasal airway resistance and might also result in an improvement of SABD according to some studies, while others did not find any improvement. The results of controversial operative treatment in nasal airway obstruction are also described and include complete healing of high degree OSAS, improvement of sleep quality, and elimination of snoring. On the other hand, surgery might also be completely unsuccessful or even induce OSAS.

CONCLUSION

As the effect of any kind of nasal operation on SABD is unpredictable from our present knowledge, the decision whether or not nasal surgery is indicated should depend on the individual situation of the patient. If OSAS is suspected, preoperative and post-operative polysomnography should be performed.

[Basal cell adenoma of Weber's glands]

INTRODUCTION

In 1967, Kleinsasser first reported about basal cell adenomas in salivary glands, which represent approximately 1-2% of all salivary gland tumors. About 70% of these tumors are found in the parotid gland. Less often the minor salivary glands are involved, particularly in the upper lip region. We would like to report on a case of occurrence in the upper pole of the palatine tonsil.

CASE REPORT

A 68-year-old woman was seen, who complained about a growth in her left tonsil. Other than a slow increase size, she had no symptoms. Examination revealed a solid tumor approximately 3 cm in diameter which displaced the upper part of the tonsil medially. In an MRI study, the neoplasia demonstrated a low signal intensity in the T1-weighted images and a high signal intensity in the T2-weighted images, which is relatively typical for a cystic structure. The tumor extended to the base of skull, and was completely resected by extended tonsillectomy. Histologic studies showed a cystic, regressive basal cell adenoma.

DISCUSSION

When compared to pleomorphic adenomas, basal cell adenomas are relatively rare in the region of the soft palate. This case is especially interesting because we assume the origin of the tumor to be in the supratonsillar salivary glands (Weber's glands) and also because of the unusually pronounced cystic regressive changes.

Lethal tuberculosis in interleukin-6-deficient mutant mice

Tuberculosis is a chronic infectious disease which causes major health problems globally. Acquired resistance is mediated by T lymphocytes and executed by activated macrophages. In vitro studies have emphasized the importance of macrophage activation for mycobacterial growth inhibition. In vivo, the protective host response is focused on granulomatous lesions in which Mycobacterium tuberculosis is contained. A cellular immune response of the T helper 1 (Th1) type is considered central for control of tuberculosis. Using interleukin-6 (IL-6)-deficient mice, we here demonstrate a crucial role of this pluripotent cytokine in protection against M. tuberculosis but not against Mycobacterium bovis BCG. Infection with M. tuberculosis was lethal for the IL-6-deficient mice at inocula that were still controlled by IL-6-competent mice. Spleen cells from M. tuberculosis-infected IL-6-/- mouse mutants produced elevated levels of IL-4 and reduced levels of gamma interferon compared to the control levels. Cytofluorometric analyses of spleen cells from M. tuberculosis-infected mice revealed more-profound alterations in T-cell ratios in IL-6-/- mice than in control mice. We assume that IL-6 contributes to host resistance by its proinflammatory activity and by its influence on cytokine secretion.

[Extracranial schwannoma of the ENT region. Review of the literature with a case report of benign schwannoma of the base of the tongue]

BACKGROUND

Schwannomas are benign, usually solitary, encapsulated neoplasms which arise from the Schwann cells of the nerve sheath. They often originate from the VIIIth cranial nerve. Extracranially, about 25% of all Schwannomas are located in the head and neck. The lateral cervical region and the mouth are the most common sites. Schwannomas arising from the base of the tongue are very rare, and only a few cases have been reported so far.

CASE REPORT

We add the case of a 31-year-old woman who had been suffering from slowly increasing dysphagia for about 4 years. Examination revealed a firm, smooth-shaped, nodular swelling about 3.0 cm in diameter arising from the base of the tongue.

SYMPTOMS AND DIAGNOSIS

The symptoms of Schwannomas are nonspecific, and depend on size and location. Sonography, CT or MRI may be helpful for estimation of the tumor margins and infiltration of surrounding structures. To confirm the diagnosis, however, microscopic examination is necessary. Characteristic histological signs are the palisading of the spindle-shaped Schwann cells around the central acellular area (so-called Verocay bodies).

THERAPY AND PROGNOSIS

The therapy of choice consists of surgical removal of the tumor; Schwannomas do not recur if they are completely removed. In contrast to multiple neurofibromas (von Recklingshausen's disease) Schwannomas almost never undergo malignant transformation.

[HIV-associated non-Hodgkin's lymphomas (HIV-NHL) in the area of the head-neck]

The life span of HIV-infected patients has increased because of anti-retroviral therapy and improved means for treating opportunistic infections. However, HIV infection and subsequent immunosuppression result in an increased risk of high-grade B-cell lymphomas. The purpose of this study was to determine the incidence, localization, clinical features, therapy and survival time of patients with HIV-related lymphomas of the head and neck. Between 1988 and 1995, 280 HIV-infected patients presented with otolaryngologic symptoms. Seventy-two (25.7%) were found to have a neoplastic disease. Fifty-six of these patients (20%) were diagnosed as having Kaposi's sarcoma and 12 (4.3%) had lymphomas. According to the Kiel classification, lymphomas were subdivided into Hodgkin's disease (2 cases) and B-cell lymphomas of high-grade malignancy (10 cases). These latter cases were centroblastic (n = 4), Burkitt's type (n = 4), anaplastic large cell (n = 1) and not classifiable (n = 1). All patients with HIV-related non-Hodgkin's lymphomas (NHL) were men and 8 were homosexuals. The mean age was 36.1 years. In addition to 7 nodal locations, high-grade B-cell lymphomas were found in the oropharynx (n = 2) and palate (n = 1). Four patients underwent chemotherapy, 1 patient underwent radiation therapy and 2 were treated with both methods. Two patients did not receive any treatment and 1 patient underwent laser therapy. The survival time depended on the previous diagnosis of AIDS, the patients' immune status and the karnofsky index. In 2 patients the lymphoma led to the diagnosis of HIV infection. Our findings show that any solitary or enlarging tumors or ulcerating lesions in the head and neck region of HIV patients must be examined histologically to exclude HIV-NHL. We also recommend that young patients with high-grade B-cell lymphomas should undergo HIV screening.

[Possibility for quantitative and frequency-specific assessment of auditory threshold with otoacoustic emissions]

BACKGROUND

Otoacoustic emissions can be used to study cochlear function in a non-invasive manner. They are an effective clinical tool for infant hearing screening. The purpose of this study was to determine their utility for a frequency-specific and quantitative estimation of the hearing threshold.

METHODS

Transiently evoked otoacoustic emissions (TEOAE) and distortion-product emissions (DPOAE) were recorded from 16 normal and 86 hearing impaired ears and correlated with their hearing threshold between 0.5 and 6.0 kHz.

RESULTS

The correlations of TEOAE and the hearing threshold ranged from 0.53 (0.5 kHz) to 0.69 (6.0 kHz), of the DPOAE from 0.51 (0.5 kHz) to 0.83 (6.0 kHz). Based on the optimal correlating OAE frequency we tried to predict the hearing threshold. We obtained 95% prediction intervals for TEOA between 19 dB (1.0 kHz) and 39 dB (4.0 and 6.0 kHz), for DPOAE between 21 dB (1.0) and 34 dB (3.0 and 4.0 kHz).

CONCLUSION

Despite their clinically irrelevant greater prediction intervals at the low frequencies, our results suggest that DPOAEs are generally more valuable for the frequency-specific estimation of the hearing threshold. Prediction intervals may improve the interpretation of OAEs.