Histopathological features in fatal COVID-19 acute respiratory distress syndrome

Background

COVID-19 acute respiratory distress syndrome (ARDS) shares the common histological hallmarks with other forms of ARDS. However, the chronology of the histological lesions has not been well established.

Objective

To describe the chronological histopathological alterations in the lungs of patients with COVID-19 related ARDS.

Design

A prospective cohort study was carried out.

Setting

Intensive Care Unit of a tertiary hospital.

Patients

The first 22 consecutive COVID-19 deaths.

Measurements

Lung biopsies and histopathological analyses were performed in deceased patients with COVID-19 related ARDS. Clinical data and patient course were evaluated.

Results

The median patient age was 66 [63–74] years; 73% were males. The median duration of mechanical ventilation was 17 [8–24] days. COVID-19 induced pulmonary injury was characterized by an exudative phase in the first week of the disease, followed by a proliferative/organizing phase in the second and third weeks, and finally an end-stage fibrosis phase after the third week. Viral RNA and proteins were detected in pneumocytes and macrophages in a very early stage of the disease, and were no longer detected after the second week.

Limitation

Limited sample size.

Conclusions

The chronological evolution of COVID-19 lung histopathological lesions seems to be similar to that seen in other forms of ARDS. In particular, lung lesions consistent with potentially corticosteroid-sensitive lesions are seen.

Histopathological features in fatal COVID-19 acute respiratory distress syndrome

Background

COVID-19 acute respiratory distress syndrome (ARDS) shares the common histological hallmarks with other forms of ARDS. However, the chronology of the histological lesions has not been well established.

Objective

To describe the chronological histopathological alterations in the lungs of patients with COVID-19 related ARDS.

Design

A prospective cohort study was carried out.

Setting

Intensive Care Unit of a tertiary hospital.

Patients

The first 22 consecutive COVID-19 deaths.

Measurements

Lung biopsies and histopathological analyses were performed in deceased patients with COVID-19 related ARDS. Clinical data and patient course were evaluated.

Results

The median patient age was 66 [63–74] years; 73% were males. The median duration of mechanical ventilation was 17 [8–24] days. COVID-19 induced pulmonary injury was characterized by an exudative phase in the first week of the disease, followed by a proliferative/organizing phase in the second and third weeks, and finally an end-stage fibrosis phase after the third week. Viral RNA and proteins were detected in pneumocytes and macrophages in a very early stage of the disease, and were no longer detected after the second week.

Limitation

Limited sample size.

Conclusions

The chronological evolution of COVID-19 lung histopathological lesions seems to be similar to that seen in other forms of ARDS. In particular, lung lesions consistent with potentially corticosteroid-sensitive lesions are seen.

Acoustic neuromas presenting with symptoms of morbus Menière

If a patient with Menière's disease or a sudden deafness does not respond to adequate therapy, an acoustic neuroma should be excluded. This is achieved by a positive contrast cisternography using multidirectional tomography. The examples might have shown that sometimes acoustic neuromas present with atypical symptoms, with sudden deafness or even with the typical symptoms of morbus menière.

[T-cartilage tympanoplasty for an open oval window]

A T shaped cartilage, placed into the open oval window, functions as a stapes. The transvers part of the T prevents a too deep insertion into the vestibule. If necessary small stripes of connective tissue seal the vestibule.

[Short and long term results of endolymphatic sac surgery: a patient-questionnaire based study]

INTRODUCTION

The endolymphatic sac surgery for the treatment of Meniere's disease has been described since the 1920s. The success rate of this technique in terms of vertigo control has been reported to be 50-80%. However, the value of this treatment method remained controversial. Furthermore, the reliable identification of the endolymphatic sac intraoperatively can be challenging in some cases. This study examines the short-, middle- and long-term results in a larger cohort of patients.

MATERIALS AND METHODS

In 74 patients, vertigo control, tinnitus and degree of satisfaction was evaluated by means of a questionnaire retrospectively. Additionally, the diagnostic value of the electrocochleography (EcochG) was determined.

RESULTS

The overall vertigo control rate was more than 70% in patients followed up for two years and has reached 81% in patients followed up for more than two years. Hearing preservation rate was 61%. Tinnitus has disappeared in 11% and improved in 23% of the patients. In 47% of the patients it was unchanged and in 19% worsened. The difference in EcochG results pre- versus postoperative was highly significant.

CONCLUSIONS

ELSS is a useful tool in the management of Ménière's disease, in particular in patients that do not benefit sufficiently from conservative therapy.

[Results in otosurgically treated patients with acoustic neuroma. Part 1: Facial nerve function after translabyrinthine and middle fossa resection]

BACKGROUND

Regardless of all efforts to preserve a residual hearing, facial nerve function is still the primary issue for patients with acoustic neuromas. Since alternative methods like the gamma-knife treatment are of increasing importance, results after surgery have to be compared and discussed critically.

PATIENTS

The results of 538 patients operated at the Dept. of Otolaryngology, Head and Neck Surgery, University of Wuerzburg between 1989 and 2004 are presented. 392 had surgery via a middle fossa, 146 via a translabyrinthine approach.

RESULTS

Shortly after surgery 82.2 % of patients showed no facial palsy. 74 patients had an incomplete, 7 a complete paresis. After 12 months 144 of the patients operated on via middle fossa approach showed no palsy, 13 had an incomplete and one a complete paresis. Out of 76 patients operated on translabyrinthine approach 75 had no paresis, one had an incomplete, and no patient had a complete paresis. There was no difference between intrameatal tumors and tumors extending beyond the porus. Regular facial nerve function was seen in 93 %, postoperatively. Permanent paresis was seen in 0.4 % of cases.

CONCLUSION

Acoustic neuroma confined to the internal meatus or with minor extension into the cerebello-pontine angle (i. e. no contact to structures of the brain stem or vessels of the posterior fossa) are feasible for resection via a middle fossa or translabyrinthine approach. The possibility of hearing preservation combined with low morbidity and good results of facial nerve function makes these approaches the treatment of choice for this group of tumors.

Klinische und audiologische Befunde von Kindern mit auditorischer Neuropathie und ihre Versorgung mit einem Cochlea-Implantat

BACKGROUND

Auditory neuropathy is a disorder characterised by preservation of outer hair cells function with normal otoacoustic emissions (OAEs), but with absent auditory brainstem responses (ABR). Perisynaptic synchronisation disorder is one of the possible pathogenesis underlying auditory neuropathy. In this paper we describe the clinical presentation and audiological findings in pediatric auditory neuropathy and its management.

PATIENTS AND METHODS

9 children with auditory neuropathy could be included in the study. An audiological evaluation was performed in all children including behavioural audiometry, measurement of the OAEs as well as electrocochleography (ECoG) and ABR recordings. Children who failed to get any benefit from conventional amplification received a cochlear implant. Prior to implantation the responses to electrical stimuli were examined with the promontory test and with the electrically evoked ABR.

RESULTS

One child showed auditory neuropathy only on one side with normal hearing thresholds on the contralateral ear. Another child had normal hearing thresholds after the follow up period. Four children received a hearing aid. But variable hearing reactions were observed. Thus in three cases a CI is planned. In three children cochlea implantation was done. Following implantation a remarkable improvement in hearing/speech capabilities with the CI compared to conventional hearing aids were observed in all three cases. Beside, these three children developed open set speech discrimination and are using now oral language for communication.

CONCLUSIONS

Auditory neuropathy is a disorder which presents with different clinical and audiological findings. Thus the management of this disorder must be an individual one. In light of our findings we support the use of cochlear implants as an option for children with auditory neuropathy in cases where conventional amplification does not work sufficiently.

Analyzing the cellular contribution of bone marrow to fracture healing using bone marrow transplantation in mice

The bone marrow is believed to play important roles during fracture healing such as providing progenitor cells for inflammation, matrix remodeling, and cartilage and bone formation. Given the complex nature of bone repair, it remains difficult to distinguish the contributions of various cell types. Here we describe a mouse model based on bone marrow transplantation and genetic labeling to track cells originating from bone marrow during fracture healing. Following lethal irradiation and engraftment of bone marrow expressing the LacZ transgene constitutively, wild type mice underwent tibial fracture. Donor bone marrow-derived cells, which originated from the hematopoietic compartment, did not participate in the chondrogenic and osteogenic lineages during fracture healing. Instead, the donor bone marrow contributed to inflammatory and bone resorbing cells. This model can be exploited in the future to investigate the role of inflammation and matrix remodeling during bone repair, independent from osteogenesis and chondrogenesis.

[Development of a new test for speech audiometry in children and results in CI children]

BACKGROUND

Speech audiometry plays an important role for hearing evaluation in children. Hearing impaired children, such as those with cochlear implant (CI) who frequently undergo testing, learn the test words by heart. Furthermore, the standard tests use words of former time.

PATIENTS AND METHODS

Using the most frequently words of modern children's literature a speech assessment test was developed for children between 1 to 8 years. The material was first evaluated on normal hearing children. In a second step the phoneme and word perception scores of 35 CI children were measured using 60 - 100 dB SPL according to the most comfortable level (MCL) in free sound field.

RESULTS

The performance-intensity function for the single words were highly comparable with those of the Freiburger or Göttinger speech perception test. The average speech reception threshold in CI children was 44 % (test I), 36 % (test II), 63 % (test III) and 69 % (test IV), respectively. Compared to the Mainzer and Göttinger speech perception test the new words were more difficult to understand than those of the known tests. However, a statistically significant difference could be noted only for test II.

CONCLUSIONS

The new developed "Würzburger speech perception test" appears to be a useful additional tool for the evaluation of hearing impaired children in addition to the standard test procedures.

Sound localization and sensitivity to interaural cues in bilateral users of the Med-El Combi 40/40+cochlear implant system

OBJECTIVE

The purpose of this study was to investigate sound localization in subjects bilaterally implanted with MED-EL COMBI 40/40+ cochlear implants. In addition, the sensitivity to interaural cues was assessed.

METHODS

In the localization test (11 subjects), CCITT noise (500 ms, original and HRTF-filtered, 70/75/80 dB sound pressure level) was presented from one of seven loudspeakers between -90 degrees and 90 degrees azimuth. The subject had to indicate which loudspeaker the noise was presented from. Sensitivity to interaural level differences (ILD) was assessed by performing localization tests (4 subjects) with the loudness of the two speech processors unbalanced to various degrees. To investigate the subjects' sensitivity to interaural time differences (ITD), lateralization was measured (7 subjects) as a function of the time difference between two Gaussian-like pulses, each directed to one of the subject's speech processor microphones by way of headphones.

RESULTS

The judgments of all subjects significantly correlated with the positions of the loudspeakers. The scatter in the judged azimuth measured by the standard deviation of the responses was on average 27.5 degrees . Unbalanced loudness of the speech processors produced a bias in azimuth toward the speech processor with the louder volume setting. The mean rate of shift was 1.4 degrees per unit on the Wuerzburg loudness scale. Six of seven subjects showed a significant sensitivity to ITDs with the approximate time difference required for complete lateralization being 1,200 micros on an average. The one subject not showing a sensitivity to ITDs performed worst in the localization test.

CONCLUSIONS

Bilateral cochlear implantation can restore spatial hearing in cochlear implant users. Both ILDs and ITDs are used by bilateral cochlear implant users in sound localization with ILDs appearing to be the dominant cue.

Bilateral cochlear implants: a way to optimize auditory perception abilities in deaf children?

OBJECTIVES

The Würzburg bilateral cochlear implant (CI) program was started with the aim to improve the patients' communicative abilities in complex listening situations. In this study, the auditory skills of children using bilateral cochlear implants were evaluated.

STUDY DESIGN AND SETTINGS

Qualitative data based on free observations in the rehabilitation setup were collected in 39 bilaterally implanted children. A speech discrimination in noise test was performed in 18 of these children; lists of bisyllabic words were presented in noise at a signal to noise ratio (SNR) of +15 dB.

RESULTS

Qualitative and quantitative data show clearly that bilateral CI improves the children's communicative behaviour, especially in complex listening situations. Children examined with the speech in noise test scored significantly better under the bilateral condition compared to the unilateral condition. Integration of the second implanted side and use of binaural information was observed to be easier and faster in children with a short time lag between both implants.

CONCLUSIONS

To be able to obtain optimal benefit from bilateral cochlear implants, an intensive rehabilitation program is necessary. The important aspects of such a program are creating realistic expectations in older children before implantation; performing the first processor fitting of the second side with the first side switched on; and separate intensive training with the new system in order to balance out the hearing competence of the second CI with that of the first.

Cochlea-Implantation: Ergebnisse und Kosten, eine Übersicht

The cochlear implantation, especially after bilateral operation provides a reliable and outstanding compensation in bilateral complete deafness or severe hearing impairment. Directional hearing can be restored with bilateral implantation so that warning signals are localized correctly and speech in noise is easier understood. Thus, rehabilitation is restored to a high degree. The involved expenses are severe, but are lower for the society when compared to the amount of money necessary to substitute a completely deaf patient lifelong.

Frequent detection of Mycoplasma pneumoniae in Bell?s palsy

The cause of Bell's palsy (BP) remains unknown despite various hints to an infectious etiology. Mycoplasma pneumoniae is a common pathogen of the respiratory tract causing pharyngitis, tracheobronchitis or pneumonia. Neurological complications are the most frequent extrapulmonary manifestation. So far, only a few case reports suggested an association between cranial nerve palsy and M. pneumoniae infection. Patients with a BP who were admitted to the Department of Otorhinolaryngology or Neurology of the University of Wuerzburg between 2000 and 2002 were tested serologically for the presence of antibodies against Borrelia burgdorferi, herpes viruses (HSV-1/2, VZV) and M. pneumoniae. The diagnosis of mycoplasmal infection was made when at least one of the following criteria was met: a threefold rise or more in the titer of antibody of M. pneumoniae in paired sample or a microparticle agglutination assay (MAG) of > or =1:40 and the detection of IgA and/or IgM antibodies in the acute phase serum. Ninety-one consecutive patients could be included. Fifteen patients showed a reactivation of a VZV ( n=12) or of a HSV-1 ( n=3) infection. In six cases the immunoblot revealed specific antibody bands for B. burgdorferi. In 24 patients (26.4%) a seroconversion of M. pneumoniae could be detected. Only two patients complained of mild respiratory symptoms. According to our results, M. pneumoniae is frequently associated with Bell's palsy. Thus, a routine screening for this pathogen, even in the absence of respiratory symptoms, is necessary.

[Long term results after cochlear implantation in elderly patients]

BACKGROUND

Cochlear implantation has become the method of choice for the treatment of deaf patients. A better technology of stimulation opened a wider field of patients suitable for cochlear implantation. Aim of the present study was to evaluate to which extent senior patients benefit by cochlear implantation.

PATIENTS AND METHODS

36 patients between 65 and 85 years were tested by the Freiburger speech test for monosyllabic words and by the HSM sentence test with and without noise. The results were compared to those of younger implanted patients (16 - 64 years, n = 101).

RESULTS

The speech perception for monosyllabic words did not differ significantly between both groups. A maximum plateau in speech perception for monosyllabic words was reached after 2 years at 55 %. The HSM sentence test revealed significant differences in the increase of speech perception between senior and younger patients in the first post surgical year. After one year elderly patients reached the same perception score as younger patients with a maximum of approximately 80 % after 3 years. At a signal to noise ratio of 15 % younger patients achieved a maximal perception of 55 % after 1 year whereas senior patients needed 4 years to reach this level.

CONCLUSIONS

Senior patients benefited by cochlear implantation to the same extent as younger patients did. Senior patients gained a similar speech perception level as younger implanted patients although the elderly needed more time to reach the same scores. Nevertheless, cochlear implantation should not be denied due to age alone.

[Experimental investigations of CO2 laser application in middle ear ossicles]

BACKGROUND

During the last few years, several laser systems have been applied for procedures in middle ear surgery. In this study, we determined the technical parameters for the dissection of the middle ear ossicles with the CO(2) laser and analyzed the histological findings.

METHODS

The malleus necks of 16 human temporal bones were dissected under standardized conditions using a CO(2) laser with a power output between 35 and 55 kW/cm(2). The specimens were fixed and histological probes of 50- micro m thickness were prepared.

RESULTS

The laser outputs led to crater diameters from 0.14 to 0.55 mm. As an analogy between laser energy and thermal tissue destruction, three zones of thermal damage were differentiated: a cinder zone, a carbonization zone, and a zone of dehydration. The metrical dimensions of these zones did not show any correlation to the applied laser energy.

CONCLUSIONS

The data of this study show that commercially available CO(2) lasers are sufficient for a safe and effective partial resection of middle ear ossicles using a power output of 35 kW/cm(2).

Meningitis following cochlear implantation: pathomechanisms, clinical symptoms, conservative and surgical treatments

Pneumococcal otogenic meningitis is a rare postsurgical complication that can develop following stapedectomy or after cochlear implantation. The bacterial infection can be fatal in some instances. A recent increase in the incidence of otogenic meningitis among cochlear implant wearers is of concern. The majority of meningitis cases are associated with a 2-component electrode manufactured by one cochlear implant company. The device with the added 'positioner' component has been withdrawn from the market (FDA Public Health Web Notification: Cochlear Implant Recipients may be at Greater Risk for Meningitis, Updated: August 29, 2002, www.fda.gov/cdrh/safety/cochlear.html). Not all cases have been subsequent to otitis media and symptoms have developed from less than 24 h up to a few years after implantation. The purpose of this paper is to review and discuss the pathogenesis, pathology/bacteriology and to elaborate on some clinical features of otogenic meningitis in implanted children and adults. Essential aspects of surgery, electrode design, and cochleostomy seal are discussed. Conclusions are drawn from the available data and recommendations are made for good practice in cochlear implantation and follow-up.

Speech understanding in quiet and noise in bilateral users of the MED-EL COMBI 40/40+ cochlear implant system

OBJECTIVE

The purpose of the study was to investigate speech understanding in quiet and noise in subjects bilaterally implanted with multi-channel cochlear implants.

DESIGN

Nine adults bilaterally implanted with MED-EL implants were included in the study. The subjects were tested in three conditions: with both implants, with the right implant only, and with the left implant only. Speech tests included monosyllables in quiet and sentences in noise (10 dB signal to noise ratio). Speech was presented from the front, and noise was presented from either 90 degrees or 270 degrees azimuth.

RESULTS

All subjects reported benefit from bilateral stimulation. Speech scores for all subjects were higher with bilateral than with unilateral stimulation. The average score across subjects for sentence understanding was 31.1 percentage points higher with both cochlear implants compared with the cochlear implant ipsilateral to the noise, and 10.7 percentage points higher with both cochlear implants compared with the cochlear implant contralateral to the noise. The average score for recognition of monosyllabic words was 18.7 percentage points higher with both cochlear implants than with one cochlear implant. All of these differences in average scores were significant at the 5% level.

CONCLUSIONS

Bilateral cochlear implantation provides a significant benefit in speech understanding in both quiet and noise.