1
|
Hellström Schmidt S, Smedenmark J, Jeremiasen I, Sigurdsson B, Eklund EA, Pronk CJ. Overuse of EEG and ECG in children with breath-holding spells and its implication for the management of the spells. Acta Paediatr 2024; 113:317-326. [PMID: 37905418 DOI: 10.1111/apa.17020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 10/15/2023] [Accepted: 10/19/2023] [Indexed: 11/02/2023]
Abstract
AIM Breath-holding spells (BHS) are common in children, but evidence-based clinical guidelines are lacking. We investigated a large population-based cohort of BHS patients, to propose a refined description of typical BHS and guidelines for its management. METHODS In a cross-sectional retrospective study, patients diagnosed with BHS in Southern Sweden 2004-2018 were recruited. Disease characteristics and diagnostic data were collected from patient medical records. RESULTS In total, 519 patients, mean age at diagnosis 19.8 ± 13.8 months with equal gender distribution, were included. In 48.3%, BHS had already been diagnosed after one spell. During spells, 78.0% of patients were unresponsive. For 71.5%, atonic, tonic, tonic-clonic or myoclonic seizures were reported, and 78.0% of patients had a spell lasting less than 1 min. Electroencephalography was conducted in 30.4% and Electrocardiography in 45.1%. Six children (3.8%) had a pathological electroencephalogram, four of which had concomitant epilepsy and only 0.9% of children had electrocardiogram findings suggesting pathology, none showing long QT syndrome. CONCLUSION Children with BHS were frequently subjected to unnecessary diagnostic interventions. We characterise a typical presentation of BHS and propose a management-algorithm, which is expected to reduce unnecessary usage of electroencephalography and electrocardiography.
Collapse
Affiliation(s)
- Sanna Hellström Schmidt
- Department of Paediatrics, Clinical Sciences Lund, Lund University, Lund, Sweden
- Chilhood Cancer Center, Skåne University Hospital, Lund, Sweden
| | - Julia Smedenmark
- Department of Paediatrics, Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Ida Jeremiasen
- The Paediatric Heart Center, Skåne University Hospital, Lund, Sweden
| | - Björn Sigurdsson
- Department of Paediatrics, Clinical Sciences Lund, Lund University, Lund, Sweden
- Department of Paediatric Neurology, Skåne University Hospital, Lund, Sweden
| | - Erik A Eklund
- Department of Paediatrics, Clinical Sciences Lund, Lund University, Lund, Sweden
- Department of Paediatric Neurology, Skåne University Hospital, Lund, Sweden
| | - Cornelis Jan Pronk
- Department of Paediatrics, Clinical Sciences Lund, Lund University, Lund, Sweden
- Chilhood Cancer Center, Skåne University Hospital, Lund, Sweden
- Wallenberg Centre Molecular Medicine and Division Molecular Haematology, Lund University, Lund, Sweden
| |
Collapse
|
2
|
Hellström Schmidt S, Tedgård U, Pronk CJ. Breath-holding spells occur disproportionately more often in children with transient erythroblastopenia. Acta Paediatr 2016; 105:1088-93. [PMID: 27060698 DOI: 10.1111/apa.13428] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2016] [Revised: 03/06/2016] [Accepted: 04/05/2016] [Indexed: 11/30/2022]
Abstract
AIM This study aimed to evaluate the concomitant occurrence and possible association of breath-holding spells (BHS) and transient erythroblastopenia of childhood (TEC). METHODS This population-based cohort study, carried out in Southern Sweden from 2004 to 2014, included patients with BHS and/or anaemia, including TEC. The subjects were evaluated for the presence of all three conditions and the diagnostic workups, disease characteristics and outcome were analysed. RESULTS We studied 443 470 children under the age of 10 years during 2004-2014. The total cohort included 321 patients (0.07%) with BHS and 366 patients with a selection of anaemia diagnoses, including 41 with TEC. We found that nine (2.5%) of the 366 patients with anaemia diagnoses also had BHS and that five (12.2%) of the 41 patients with TEC also had BHS. Treatment for anaemia resolved BHS in a number of patients. CONCLUSION Our population-based analysis revealed an overrepresentation of BHS among children with TEC, and we identified five patients with concomitant TEC and BHS. We found that correcting anaemia was an effective means of ameliorating potentially debilitating BHS and that the presence of concomitant BHS and TEC was more common than previously assumed.
Collapse
Affiliation(s)
| | - Ulf Tedgård
- Department of Paediatric Oncology/Hematology; Skane University Hospital; Lund Sweden
| | - Cornelis J.H. Pronk
- Department of Paediatric Oncology/Hematology; Skane University Hospital; Lund Sweden
- Medical Faculty; Division of Molecular Hematology; Institution for Laboratory Medicine; Lund University; Lund Sweden
| |
Collapse
|
3
|
Hermans HJE, Schmidt SH. [A blind bicycle repair man at the Stedelijk Museum: the exhibition and congress 'labour for the disabled' of 1928]. Gewina 2003; 25:226-40. [PMID: 12683366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
In the 1920's concern about the rising number of disabled unemployed urban poor led to the founding of the AVO (Dutch organization for labour care for the disabled) in 1927. The AVO presented the problem of the vulnerability of the physically and mentally disabled in the labour market as a matter of collective responsibility. At the Amsterdam AVO congress of 1928 expert contributors discussed the economic, social and medical aspects of disability and work. Simultaneously, a museum exhibition aimed at arousing the interest of the general public and at promoting a more understanding attitude towards the disabled. Though the twofold AVO manifestation raised an immediate favourable general response and the subject was put on the political agenda, the subsequent economic recession and war forestalled concrete measures. Essentially it was the first public debate on disability in the Netherlands.
Collapse
Affiliation(s)
- H J E Hermans
- AMC, Afdeling Sociale Geneeskunde, Universiteit van Amsterdam
| | | |
Collapse
|
4
|
Schmidt SH. Comparison of tympanic membranes. Arch Otolaryngol Head Neck Surg 2001; 127:468-9. [PMID: 11296066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
|
5
|
Schmidt SH, Oort-Marburger D, Meijman TF. Employment after rehabilitation for musculoskeletal impairments: the impact of vocational rehabilitation and working on a trial basis. Arch Phys Med Rehabil 1995; 76:950-4. [PMID: 7487437 DOI: 10.1016/s0003-9993(95)80073-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
OBJECTIVE To investigate to what extent vocational rehabilitation and working on a trial basis have an impact on employment after rehabilitation. DESIGN Follow-up survey, conducted in 1991, among all patients, aged 14 to 64, who were treated between 1984 and 1987. SETTING An out-clinic department of a rehabilitation center in the west of The Netherlands. SUBJECTS 395 patients (59% of the original sample) participated in the study. They suffer from musculoskeletal impairments due to back pain (41%), brain injury (20%), neurological disorder (12%), trauma to the upper and/or lower extremities (8%), rheumatoid arthritis (7%), or other disorders (12%). No differences were found between those who did and those who did not respond with regard to age, gender, marital status, disorder, work experience, and participation in vocational rehabilitation. MAIN OUTCOME MEASURE Odds ratio of having a paid job after rehabilitation. RESULTS Participation in vocational rehabilitation and working on a trial basis depends on age, gender, work experience, and disorder. When statistically controlled for these variables vocational rehabilitation (odds ratio 1.96; 95% confidence interval 1.12 to 3.42) and working on a trial basis (odds ratio 3.26; 95% confidence interval 1.74 to 6.11) proved to have a significant impact on employment after rehabilitation. CONCLUSIONS The findings suggest that rehabilitation programs that aim specifically at promoting employment for people with disabilities are effective, in particular when they take place in both a laboratory and a natural setting. The validity of this suggestion must be further tested by means of an experimental design.
Collapse
Affiliation(s)
- S H Schmidt
- Institute of Social Medicine/Institute for Work and Health, University of Amsterdam, The Netherlands
| | | | | |
Collapse
|
6
|
|
7
|
Abstract
The etiology of cholesteatoma is still enigmatic. Of the current theories, none has been confirmed with adequately convincing evidence. A completely suitable animal model has not hitherto been available and there is still a need for further experimental studies of this entity. As a possible experimental model we suggest dimethyl-benzanthracene induced cholesteatoma in the rat.
Collapse
MESH Headings
- 9,10-Dimethyl-1,2-benzanthracene/adverse effects
- Animals
- Cholesteatoma, Middle Ear/chemically induced
- Cholesteatoma, Middle Ear/pathology
- Disease Models, Animal
- Ear Canal/drug effects
- Ear Canal/pathology
- Ear, Middle/drug effects
- Ear, Middle/pathology
- Epithelium/drug effects
- Epithelium/pathology
- Eustachian Tube/drug effects
- Eustachian Tube/pathology
- Keratins/drug effects
- Otitis Media, Suppurative/chemically induced
- Otitis Media, Suppurative/pathology
- Rats
- Rats, Sprague-Dawley
- Tympanic Membrane/drug effects
- Tympanic Membrane/pathology
Collapse
Affiliation(s)
- S H Schmidt
- Department of Otorhinolaryngology, University of Umeå, Sweden
| | | |
Collapse
|
8
|
Schmidt SH, Meijman TF, Scholten A, van Oel CJ, Oort-Marburger D. Factors contributing to job satisfaction following rehabilitation for musculoskeletal impairments. J Occup Rehabil 1993; 3:213-222. [PMID: 24243436 DOI: 10.1007/bf01097431] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The study investigates whether changing jobs is related to work-related well-being of people with musculoskeletal impairments. In order to assess this relationship subjects who began new jobs after rehabilitation (N=52) were compared with subjects who returned to their former employment (N=63). Work-related well-being was measured by means of the scales "job satisfaction" and "need to recover after work." After controlling for individual characteristics (gender, age, working hours per week, and pain complaints) and job characteristics (job demands and decision latitude), job satisfaction could be predicted by job change. Recovery need after work was predicted by pain complaints, job demands, and decision latitude, but not by job change.
Collapse
Affiliation(s)
- S H Schmidt
- Institute of Social Medicine/Research Centre "Work and Health," Faculty of Medicine, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands
| | | | | | | | | |
Collapse
|
9
|
Schmidt SH, Hellström S. Phenol anesthesia of the tympanic membrane in purulent otitis media: a structural analysis in the rat. Eur Arch Otorhinolaryngol 1993; 249:470-2. [PMID: 8442942 DOI: 10.1007/bf00168857] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
In the present study, local anesthetics were applied to the tympanic membrane (TM) of rats following experimentally evoked purulent otitis media (POM). The structure of the TM was evaluated 24 h, 2 weeks and 3 months after application of phenol to a discrete are of the right TM. The left ear was used as a control. POM induced swelling of all tissue layers of the pears tensa. The tissues were invaded by inflammatory cells and disintegrated. The fibrous layer also dissolved, leaving spontaneous perforations. However, phenol on inflamed TMs did not further alter the TM structure. These findings infer that the injurious effect of topical anesthesia on the intact TM is more or less negligible when applied to diseased TMs.
Collapse
Affiliation(s)
- S H Schmidt
- Department of Otorhinolaryngology & Head and Neck Surgery, University of Umeå, Sweden
| | | |
Collapse
|
10
|
Abstract
In recent years, the rat has attracted increasing interest as an experimental animal in otological research. In the present study, the structure of the rat tympanic membrane (TM) is compared with that of a traditional experimental animal, the guinea pig, and with the human TM. The normal guinea pig TM consists mainly of a single layer of coarse fiber bundles, in contrast to the more solid layers of radial and circular fibers in man and rat. The investigation reveals similar architectural features in the rat and human TM, whereas the guinea pig TM differs structurally.
Collapse
Affiliation(s)
- S H Schmidt
- Department of Otorhinolaryngology, Head and Neck Surgery, University of Umeå, Sweden
| | | |
Collapse
|
11
|
Schmidt SH, Anniko M, Hellström S. Electrophysiological effects of the clinically used local anesthetics lidocaine, lidocaine-prilocaine and phenol on the rat's inner ear. Eur Arch Otorhinolaryngol 1990; 248:87-94. [PMID: 2282220 DOI: 10.1007/bf00240226] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Local anesthetics, even if applied to the outer ear canal, may still enter the middle ear, running the risk of penetrating the round window. To elucidate the effect of certain topical anesthetics on the inner ear, the round window niche in the laboratory rat's middle ear was exposed separately to lidocaine, lidocaine-prilocaine and phenol. Auditory brain-stem responses (ABR) were recorded at 2, 4, 6, 8, 12, 16, 20, and 31.5 kHz before the application, and 24 h, 3 weeks, 2 months and 6 months after exposure. After terminating the 6-month ABR measurements, the animal were sacrificed and the temporal bones fixed and decalcified for light microscopic analysis. All three drugs affected the ABR thresholds and the cochlear morphology with a pattern characteristic for each drug. At 24 h, all three substances caused severe impairment of ABR thresholds, followed by a period of restitution lasting up to 2 months. Even 6 months after exposure, the ABR thresholds at and above 12 kHz were impaired, as compared with the pretreatment level, for all substances tested. In the lower frequencies the original ABR threshold was reached in the order: (1) lidocaine, (2) lidocaine-prilocaine, (3) phenol. The cochlear structures were unaffected by lidocaine, whereas lidocaine-prilocaine and phenol caused morphological damage which was most pronounced after exposure to phenol. The heterogeneity of the changes in the ABR thresholds suggests differences in the mechanism of action of each type of local anesthetic investigated. The effects following lidocaine were transient. However, clinicians must be aware of the ototoxic potential of both lidocaine and phenol.
Collapse
Affiliation(s)
- S H Schmidt
- Department of Oto-Rhino-Laryngology, University of Umeå, Sweden
| | | | | |
Collapse
|
12
|
Abstract
The effects of topically applied hydrocortisone on experimental tympanic membrane (TM) perforations in rats were evaluated by otomicroscopy and light microscopy. Standardized TM perforations, occupying the whole upper rear quadrant, were performed, and a 2% hydrocortisone suspension (CORT) was applied once daily for 10 consecutive days. Application of CORT caused a delayed healing pattern, and even at 1 month only 2 of 12 perforations had healed. The keratinizing squamous epithelial cells of the TM appeared hypertrophic, whereas hyperplasia, characterizing a nontreated healing TM perforation, was less prominent. The connective tissue layer of the CORT-treated TM was invaded by abundant inflammatory cells, mainly polymorphonuclear leukocytes. Also, when applied to an intact TM, CORT caused hypertrophy of the epidermal cells and an inflammatory reaction within the TM.
Collapse
Affiliation(s)
- O Spandow
- Department of Otorhinolaryngology & Head and Neck Surgery, University Hospital, Umeå, Sweden
| | | | | |
Collapse
|
13
|
Carlsöö B, Franzén L, Henriksson R, Löfroth PO, Schmidt SH. Bilateral squamous cell carcinoma of the middle ear. Int J Radiat Oncol Biol Phys 1990; 19:506-7. [PMID: 2394631 DOI: 10.1016/0360-3016(90)90571-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
14
|
Schmidt SH, Hellström S, Anniko M. Structural effects of the topical lidocaine-prilocaine anesthetic Emla on the tympanic membrane. Arch Otorhinolaryngol 1988; 245:136-41. [PMID: 3178560 DOI: 10.1007/bf00464014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A eutectic mixture of two anesthetic solutions is that of lidocaine and prilocaine, which is available commercially as Emla (eutectic mixture of local anesthetics). This solution is commonly used in clinics in superficial skin surgery and when inserting intravenous catheters, and we also wanted to determine its surface effects when applied onto the tympanic membranes (TM) of rats and guinea pigs as animal models. The animals were observed by otomicroscopy for 2 weeks up to 5 months after administrations of the anesthetic solution. Tissue specimens were then obtained for light microscopy and fine structural analysis. The application of Emla caused minor structural changes to the rat TM, but hardly any alterations to that of the guinea pig. The changes displayed were an overall increased thickness, with typical submucosal edema but only slight epithelial reaction. In comparison with previous results with lidocaine, phenol and Bonain's solution, Emla seemed to be harmless to the structure of the TM. However, the efficacy of Emla as a topical TM anesthetic remains to be proved in future clinical trials.
Collapse
Affiliation(s)
- S H Schmidt
- Department of Otorhinolaryngology and Head and Neck Surgery, University of Umeå, Sweden
| | | | | |
Collapse
|
15
|
Abstract
Instillation of EMLA, a new local anesthetic, into the middle ear of the guinea pig caused severe morphological damage to the organ of Corti in the first 4 mm from the round window. Further up the cochlea, only derangements of the stereocilia were found. The extent of morphological damage was the same, whether the agent was administered once or several times. The ototoxic potential of EMLA was obvious and is probably due to direct damage in areas where present in high concentrations. Over a short distance of approximately 0.1 mm there is a transition from a total destruction of the organ of Corti to a completely normal morphology.
Collapse
Affiliation(s)
- M Anniko
- Department of Oto-Rhino-Laryngology-Head and Neck Surgery, Umeå University Hospital, Sweden
| | | |
Collapse
|
16
|
Anniko M, Hellström S, Schmidt SH, Spandow O. Toxic effects on inner ear of noxious agents passing through the round window membrane. Acta Otolaryngol Suppl 1988; 457:49-56. [PMID: 2648756 DOI: 10.3109/00016488809138884] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The effects on inner ear of Xylocain, EMLA, phenol, endotoxin and hydrocortisone were analysed before treatment and 24 h-6 months after instillation of each drug into the round window (RW) niche, where the substance was left. Inner ear function was determined by repeated auditory brainstem recordings (ABR). All cochleae were analysed morphologically at the light microscopic level. Hydrocortisone, Xylocain and endotoxin caused functional changes without morphological correlates, even at long-term follow-up. In contrast, phenol and EMLA caused both functional impairment and graded morphological damage to the organ of Corti in the basal coil. Outer hair cells (OHC) were more vulnerable than inner hair cells (IHC).
Collapse
Affiliation(s)
- M Anniko
- Department of Oto-Rhino-Laryngology and Head and Neck Surgery, University Hospital, Umeå, Sweden
| | | | | | | |
Collapse
|
17
|
Schmidt SH, Spithoven AH. [The aged and job perspectives. An exploration]. Tijdschr Gerontol Geriatr 1986; 17:183-9. [PMID: 2947352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The expulsion of older people from the labour market is observed with some resignation by policy-makers. One of the consequences is the lack of opportunities for older people to participate in social life. This process of expulsion started as far back as the mid-sixties. Initially the Disablement Acts, and more recently the Unemployment Acts and Early Retirement measures were used to this end. After describing these processes, attention is paid to the rehabilitation activities for the older people who are entitled to payments according to the Disablement Acts. Some empirical data are presented. It is shown that hardly any activities have been undertaken that result in the rehabilitation of older disabled people. This situation has contributed to create an atmosphere in which the opinion prevails that older people are superfluous in the labour market. Taking into account the development of employment in agriculture, manufacturing and services, there are perspectives for older people to work in the service sector.
Collapse
|
18
|
Abstract
With the rat tympanic membrane used as a model, various topical anesthetics in current clinical use (phenol, Bonain's liquid, and Xylocaine spray) were tested. Structural changes were observed for up to five months from the time of anesthetic application. The most protracted changes affect the lamina propria, which exhibits a pronounced thickening. The extent of the changes, however, differs according to the agent used; for example, phenol applied to discrete areas exhibited the least widespread changes. In the tympanic portion of the lamina propria, the connective tissue was loosely packed with less regularly arranged collagen fibers, while a tightly packed fiber bundle existed on the meatal side. It is inferred that the submucosal connective tissue layer is the portion of the connective tissue layer where the remodeling and reconstruction of the fibrous layer occur.
Collapse
|
19
|
Abstract
The tympanic membrane of the rat was studied ultrastructurally after application of a local anaesthetic--lidocaine spray. Already after 10 min, degenerative changes--or even necrosis--were observed on both epithelial surfaces of the eardrum. Later on, a marked hyperplasia of the epidermal layer was most characteristic, as was a proliferation of the fibroblasts of the subepithelial connective tissue. After 3 weeks the eardrum had not regained its normal appearance. No perforations were encountered and only minute substructural changes could be detected within the fibrous layer.
Collapse
|
20
|
Abstract
Topical agents used in office procedures for tympanic membrane anaesthesia have been considered to cause damage to the membrane. Four different anaesthetic agents have been compared as regards their histopathological effects for a period of up to 2 weeks after application. An etching effect is obvious when using these clinically potent agents, but it seems reversible and does not leave remaining structural changes.
Collapse
|
21
|
Schmidt SH, Hellström S, Carlsöö B. Short-term effects of local anaesthetic agents on the structure of the rat tympanic membrane. Arch Otorhinolaryngol 1984; 240:159-66. [PMID: 6477294 DOI: 10.1007/bf00453474] [Citation(s) in RCA: 2] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Four different local anaesthetic agents were tested on the tympanic membrane of the rat in order to detect any structural changes. Specimens were obtained for examination under the light microscope 10 min, 24 h, 1 week, and 2 weeks after exposure to each anaesthetic. The histological changes observed were, in general, rather similar for all agents tested, although certain differences were noted. The initial change observed was damage of the outer epithelial layers, later also accompanied by changes in the corresponding endothelial cover. No perforations were observed macroscopically. The healing process was characterized by hyperplasia of the connective tissue layers of the drum. However, the most prominent feature of this process was the hyperplastic epithelium, ingrowing from the periphery of the membrane to cover denuded areas. During certain stages of the healing process the thickness of the membrane amounted to 40 times that of the normal drum. The initial changes appeared severe both with the clinically more potent and effective anaesthetics (phenol and Bonain's liquid), and with Xylocaine spray.
Collapse
|