Foreign body neonatal otitis media in infants

HYPOTHESIS

An influx of amniotic fluid cellular content (AFCC) into the middle ears during birth may lead to the development of a chronic inflammatory process in the form of varying amounts of granulation tissue even if signs of otitis media are absent. This foreign body neonatal otitis media may predispose the child to recurrent otitis media.

BACKGROUND

Foreign body neonatal otitis media caused by AFCC was described by Aschoff and elaborated by Wittmaack 100 years ago. Recent studies have shown how AFCC spreads to various middle ear compartments and causes histologic changes, the severity of which is related to the amount of AFCC. Specific elements become phagocytized after the first months of life but have caused the formation of inflammatory polyps and granulation tissue with round cell secretions in the meantime.

METHODS

Ten temporal bones from the Temporal Bone Foundation, derived from infants aged 5 months to 1 year 11 months, were serially sectioned at 20 microm, saved at 0.2-mm intervals, numbered, and stained with hematoxylin and eosin. Every slide was studied for the presence, nature, and stage of pathologic tissue changes of the middle ear and the mastoid antrum.

RESULTS

Pseudocystic granulation tissue was massive in the temporal bone of the 8-month-old child born through thick meconium. Severe changes were present in the temporal bones of two infants aged 5 months, one of which showed traces of AFCC. In the temporal bones of two older children, long-standing changes were minor, one of them still showed traces of AFCC. Fresh acute changes and long-standing histologic changes occurred side by side.

CONCLUSIONS

Neonatal otitis media caused by AFCC can give rise to extensive granulation tissue and round cell secretion, which is likely to make the ear susceptible to infectious otitis media. Cumulative development of granulation tissue as a result of infection may lead to blockage of attic aeration and drainage pathways, causing irreversible adhesive otitis media. A data base should be formed of all neonates born through meconium-stained amniotic fluid to allow a comparison with those born through clear fluids. Surgery with the creation of auxiliary aeration pathways becomes advisable in the treatment of ears with massive development of granulation tissue.

Selective inner hair cell loss in premature infants and cochlea pathological patterns from neonatal intensive care unit autopsies

BACKGROUND

Deafness and handicapping sensorineural hearing impairment occur frequently in neonatal intensive care unit survivors for unknown reasons.

PATIENTS AND METHODS

Hearing was tested early and repeatedly in neonatal intensive care unit patients with an auditory brainstem response (ABR) screener. The temporal bones of 15 nonsurvivors (30 ears) were fixed promptly (average, 5 hours) after death for histological evaluation.

RESULTS

Among these patients, 12 failed the ABR screen bilaterally, 1 passed unilaterally, and 2 passed bilaterally. Cochlear histopathologic conditions that could contribute to hearing loss included bilateral selective outer hair cell loss in 2 patients, bilateral selective inner hair cell loss in 3 (all premature), and a combination of both outer and inner hair cell loss in 2. Other hair cell abnormalities were noted; the 2 infants who had passed the ABR screen demonstrated normal histological features. Neuronal counts were normal.

CONCLUSIONS

Auditory brainstem response failure among these neonatal intensive care unit infants who died was extremely common in part owing to an unexpected histological alteration, selective inner hair cell loss among premature newborns, that should be detectable uniquely by the ABR testing method. Additional histological patterns suggest more than one cause for neonatal intensive care unit hearing loss. Hair cell loss patterns seem frequently compatible with in utero damage.

Spread and fate of amniotic fluid cellular content in the middle ear

In this study, 24 temporal bones with an age range from neonates to 23-month-old infants were serially sectioned and studied for the spread and fate of amniotic fluid cellular content (AFCC) in the middle ear and mastoid. Most children had had either a moderate or massive contamination. AFCC clusters were found to spread to all compartments, with the sites of predilection being the stapes region, the lower lateral attic and the tympanic isthmus. AFCC created an intensive foreign body giant cell reaction and the foreign material practically dissolved in 5 months as a result of the organization process. Tiny remnants of AFCC appeared as late as 15 months after birth. It seems likely that AFCC contamination predisposes the ears to recurring otitis media. The sequalae of the massive granulation tissue development involves obliteration of Prussak's space and its aeration routes, as well as blockage of the tympanic isthmus, leading to extensive disease in the major attic compartments.

Aeration and drainage pathways of Prussak's space

OBJECTIVE

the purpose of this study was to document the aeration and drainage pathways of Prussak's space.

METHODS

55 temporal bones with an age range from neonate to 11 years of age were serially sectioned to 20 microns, every 10th section was saved and stained by Hematoxylin eosin. Each consecutive section was studied as to the connections of Prussak's space to adjacent compartments and measurements of the dimensions were made for both Prussak's space and its aeration pathways.

RESULTS

the classic aeration pathway via the posterior pouch, as described by Prussak in 1867, was found in 34 ears (62%). In 19 (36%), aeration occurred superior to the posterior pouch in the region of the lower lateral attic and the upper mesotympanum. In these ears the posterior pouch had formed, but its superior limit ended blindly in the tympanic membrane. In two temporal bones the aeration pathway was from the anterior pouch and in these cases also a blind posterior pouch had developed. In one temporal bone an auxiliary pathway in addition to the route via the posterior pouch was through the roof (the lateral malleal ligamental fold) of Prussak's space to the overlying lateral malleal space. The height of the posterior pouch varied with a range from 0.5 to 2.4 mm, and the greatest width, which was towards the posterior tympanic spine, varied from 1.6 to 3.2 mm. The superiorly blind posterior pouch was shorter, ranging from 0.4 to 1.2 mm in height. The most frequent route of the chorda tympani nerve was running from 0.5 to 1 mm medial to the posterior malleal ligament in the anterior half of the pouch, joining it posteriorly, or it was connected to it by a short fold, 37 ears (67%). In 18 cases (33%) the chorda was surrounded by its own fold, thus entirely separate from the posterior malleal ligamental fold during its entire course across the tympanum.

CONCLUSIONS

we have made a detailed documentation of the aeration and drainage pathways of Prussak's space and the findings concur, with important modifications, with Prussak's original description. There is no evidence for contemporary claims that Prussak's space would be aerated superiorly between the lateral incudal and malleal folds. Prussak's space and its aeration pathway is an unit of its own, entirely separate of the major epitympanic compartments which are aerated via the tympanic isthmus. Due to frequent disease processes in the lower lateral attic and posterior mesotympanum, Prussak's space and its aeration pathway are likely to become blocked. This may lead to obliteration of Prussak's space and to the development of retraction pocket or papillary ingrowth cholesteatoma.

Effect of amniotic fluid cellular content on attic aeration pathways: histologic observations of infants aged 2 to 4 months

HYPOTHESIS

The tissue-fixed amniotic fluid cellular content (AFCC) in the middle ear and mastoid antrum causes foreign body type reactions that may later severely restrict the aeration pathways to the main attic and to Prussak's space.

BACKGROUND

It was shown by Aschoff 100 years ago that AFCC remained in the neonate ears and caused sterile otitis media. Recent data show that children born through thick meconium are at risk for large quantities of AFCC entering the middle ear cleft, the ensuing inflammatory reaction being related to the amount of AFCC. Spread of AFCC in the neonate occurred along the aeration pathways with corresponding tissue fixation but further systematic data in young infants are lacking.

METHODS

Five temporal bones of three infants aged 2 to 4 months were embedded in celloidin, serially sectioned at 20 microns, and every 10th section stained with Hematoxylin and eosin and mounted on slides. All slides were studied and relevant details of aeration pathways and all compartments photographed.

RESULTS

The histologic changes were characterized by the development of masses of pseudocystic granulation tissue, with some remnants of the original AFCC, mainly in the form of fragments of hair. The tympanic isthmus was involved to varying extent, maximally to half of its size. Posterior tympanum and the stapes region had masses of fresh granulation tissue, the maturing of which might cause marked indrawing of the posterior pars tensa and further reduction of the tympanic isthmus. Aeration of Prussak's space was severely involved in two bones, favored by the narrow pathway through the posterior pouch. Features of recent acute or secretory otitis media were associated with the early changes caused by AFCC.

CONCLUSIONS

The granulation tissue in this age group is immature and its final fate is decided by the nature of the future ear disease. If the AFCC contamination is slight, the granulation tissue after maturing may appear only in the form of thin cords and sheets, a frequent chance finding in ear surgery. Large amount of AFCC may lead to chronic inflammation, which may predispose the child to recurring middle ear infections during infancy. Further histologic and clinical studies in older infants and young children are needed to find out the final outcome after a massive AFCC contamination of the new-born middle ear.

Supratubal recess in neonates and infants

OBJECTIVE

The fetal development of the supratubal recess and of the tensor fold was described by Hammar in 1902. Recent studies claim that neither structure is regularly present in neonates and controversial views have been presented of the separation of the anterior attic and supratubal recess. The objective of this study is to clarify these issues.

METHODS

Twenty temporal bones, 13 neonate and seven infant, were studied either by microdissection of fresh (five bones) or formalin stored (two) specimens, or by serial sectioning after formalin fixation and decalcification (13 bones). The serial sections were cut to 20 microm, every tenth section saved and stained by hematoxylin eosin.

RESULTS

In all specimens the separating structure between the anterior attic and supratubal recess was the tensor fold. It was intact in 15 bones while five showed a membrane defect. In vertically oriented folds the recess was deep and in horizontally oriented folds shallow. In 19 bones the tensor fold inserted superiorly to a soft tissue insertion ring of varying thickness and only once directly to a shallow transverse crest. The breadth of the tensor fold near the tensor tendon showed only little variation, whereas its height, and the distance from the tensor tendon to the supratubal tegmen varied in larger limits.

CONCLUSIONS

The tensor fold and the supratubal recess are present already in the neonate and thus develop during the fetal period. The shape of the recess is determined by the fold direction and its size grows in conjunction with the other middle ear spaces. The transverse crest has no apparent influence on the position of the tensor fold. The easiest method to study the integrated whole of the anterior attic and supratubal recess is to view them alternatively from the anterior and superior microdissection approaches. Clinically, removal of the tensor fold creates an efficient additional aeration route from the supratubal recess to the anterior attic.

Spread of amniotic fluid cellular content within the neonate middle ear

Six full-term neonatal temporal bones, with meconium contaminated amniotic fluid aspiration of varying degrees, were serially sectioned at 20 microm and every tenth section was stained by hematoxylin eosin and mounted on slides. All stained sections were studied, the data recorded and relevant details of all compartments photographed. In addition, four normal neonate temporal bones were studied, one by serial sectioning and three by microdissection. The lateral incudomalleal and tensor folds were present in all, membrane defects in the tensor fold were seen in two normal ears. Three ears in the aspiration group had much fetal tissue present rendering Prussak's space small. Four ears with aspiration had remnants of incus intercrural (medial) folds. The amniotic fluid cellular content (AFCC) was sparse or nonexistent in the supratubal recess, Prussak's space and hypotympanum. It concentrated to the areas around the stapes, to sinus tympani and round window niche, to lower lateral attic and posterior pouch, medial attic and in lesser amounts to superior attic, mastoid antrum and air cells. Massive amounts of AFCC in tympanic isthmus and posterior pouch may lead to formation of granulation tissue and blockage of the aeration pathways to attic proper and to Prussak's space. These changes may initiate the development of chronic secretory otitis media in infants.

Embryonic middle ear mesenchyme disappears by redistribution

OBJECTIVE

The fate of embryonic middle ear mesenchyme from a postgestational infant ear has been speculative. Recently a volume analysis of human neonatal temporal bones demonstrated that embryonic mesenchyme disappeared by redistribution and thinning to surface a growing middle ear space. If this model is accurate, interaction with amniotic fluid and the gestational environment should not influence mesenchymal behavior. Therefore an opossum marsupial model was compared with human data.

METHODS

The temporal bones of opossum pups (20 to 36 days of age) were sectioned for histologic analysis. Computations were made for the volume of the middle ear air cavity (VAC), volume of the bone cavity (VBC), volume of mesenchyme (VM), and percentage of the middle ear occupied by mesenchyme (%M), which were plotted against height using regression statistics. These data were compared with human neonatal (0 to 30 days of age) temporal bones.

RESULTS

In both the opossum and the human the VAC and the VBC increased in parallel with growth of the body. In the opossum the VAC and VBC both grew at 0.148 mm3/mm of body length. In humans, both the VAC and VBC grew 6.1 mm3/cm of body length. The VM in the opossum remained constant at 0.98 mm3, regardless of body length. In humans the VM remained constant at 71.7 mm3, regardless of body length. Therefore the %M proportionately decreased inversely with increasing ear size in both the opossum and the human neonate.

CONCLUSION

This study supports a simple and credible explanation for the illusion of mesenchymal disappearance in the neonatal middle ear. The mesenchymal connective tissue redistributes to cover a larger surface area in a persistently enlarging cavity. These findings occur in different species, whether gestation is completed in an intrauterine or an extrauterine environment.

The origin of congenital cholesteatoma

OBJECTIVE

This study aimed to document histologically the origin of congenital cholesteatoma in neonatal temporal bones.

STUDY DESIGN

The study design was a systematic analysis of pediatric temporal bones.

SETTING

The study was performed at the temporal bone laboratory, Tufts University School of Medicine and New England Medical Center, Boston, Massachusetts.

RESULTS

We describe histologic findings of a congenital cholesteatoma and a squamous epithelial rest in two postpartum patients. In both patients, the masses were asymptomatic and occurred in the anterosuperior quadrant of the middle ear cleft. This is the first histologic documentation of postpartum congenital cholesteatoma.

CONCLUSIONS

We believe that these cases represent the first clear histologic documentation of the origin of congenital cholesteatoma.

Juvenile keratin inoculation induces chronic ear pathology

OBJECTIVE

Human neonatal temporal bones frequently show the formation of granulation tissue provoked by amniotic fluid keratin contents, desquamated keratinized epithelial cells and lanugo hair. Similar histopathologic findings have been produced previously in a short-term animal model. To test the hypothesis that those short-term pathologic observations could have theoretical relevance for ear disease in older patients, a longer term animal model study was necessary.

METHODS

Into the right bulla of 10 chinchilla pups was placed an aliquot of autogenous, nonviable epidermal scrapings and hair. Into the left bulla was placed 1 mm2 viable autogenous epidermal tissue. Animals were killed at intervals up to 11 months and then studied by light microscopy.

RESULTS

Chronic ear histopathologic changes such as granulation tissue, osteoneogenesis, adhesions, and cholesteatoma were present. Over time, these secondary pathologic changes became more obvious than the initial keratin implant.

CONCLUSIONS

The authors conclude that chronic pathologic changes resembling human ear disorders persist and that this model further extends the hypothesis that prenatally acquired keratin eventually could account for some cases of human ear disease.

What High School Students Think of a Nursing Career: A Survey of Dade County Senior High Schools

Using a cross-sectional design, we surveyed 700 10th and 11th-grade students in Dade County, Florida, to examine high school students' opinions of a nursing career and the relationships among students' opinions and several variables. Of a possible range of opinion scores from 14 to 56, the mean opinion score for the sample was 40.92 (SD = 7.8). While age had no significant correlation with nursing opinion scores, they were influenced significantly by gender, the students' desired occupation, and the opinions of parents, friends, and guidance counselors. Although only 28 (7%) of the students selected nursing as their desired occupation, 119 (24.5%) considered nursing one of their alternatives prior to making a decision. These findings have important implications for the recruitment of high school graduates into nursing.

Evaluation of mannitol, lactulose and 51Cr-labelled ethylenediaminetetra-acetate as markers of intestinal permeability in man

1. Factors affecting the intestinal uptake and urinary excretion of mannitol, lactulose and 51Cr-labelled ethylenediaminetetra-acetate (51Cr-EDTA), have been investigated in normal subjects and three patients with ileostomy. 2. The distribution volume of markers within the body, the rate of disappearance from plasma and renal clearance were assessed after an intravenous injection of a mixture of mannitol (2 g), [14C]mannitol (10 microCi), lactulose (0.1 g) and 51Cr-EDTA (5 microCi). 3. The urinary recovery of all the intravenously administered markers was close to 100%. Distribution volumes and patterns of excretion were virtually identical. Oxidation of intravenously administered mannitol accounted for only about 1% of the dose. 4. The passage of an orally administered mixture of markers was traced through the intestine and into urine. Transit time through the gastrointestinal tract was measured by the breath hydrogen method and by radionuclide scanning. 5. The passage of markers from mouth to the large bowel was essentially complete by 3.5 h. In some subjects the marker appeared in the large bowel as early as 30-40 min but in others it took three times as long. 6. After an oral dose the urinary excretion of mannitol fell progressively from 2 to 6 h, whereas the excretion of lactulose and 51Cr-EDTA increased slightly. As a consequence the lactulose/mannitol and 51Cr-EDTA/mannitol ratios in urine collected between 0 and 2 h were more than twofold higher than in urine collected between 4 and 6 h (P less than 0.001). After 6 h, the urinary excretion

Radionuclide tests for the assessment of intestinal permeability

14C labelled-D-mannitol and aquo (ethylene-diaminetriacetoacetic acid) 51chromium (III) (51Cr EDTA) have been evaluated as markers of intestinal permeability in twenty-four healthy control subjects, sixteen patients with recently diagnosed coeliac disease and twenty subjects with coeliac disease in remission on a gluten-free diet. The percentage excretion of 14C mannitol in urine collected for 6 h was significantly less in patients with coeliac disease (mean 6.7%) than controls (mean 13.5%). Conversely the excretion of 51Cr EDTA was significantly greater in patients with coeliac disease (mean 1.23%) compared with controls (mean 0.28%). The mean ratio of the percentage excretion of 51Cr to the percentage excretion of 14C was 0.29 in patients with untreated coeliac disease compared with 0.023 for healthy control subjects (P less than 0.001). Patients with untreated coeliac disease were clearly separated from control subjects by use of the 51Cr EDTA: 14C mannitol ratio but not by the excretion of independent markers.

Histological observations of amniotic fluid cellular content in the ear of neonates and infants

Amniotic fluid cellular content (AFCC), especially keratinized, non-nucleated squamous epithelial cells and lanugo hair, have been detected in the fetal and neonatal ear. We wished to evaluate the incidence, amount and histological findings of AFCC in the neonatal and early infant period. Temporal bones (n = 63) from children aged 10 min to 70 days were examined. AFCC was discovered in 39 of 43 bones in neonates. In children of 31-70 days of age, AFCC was present in 11 of 20 bones. A measurement of the amount of AFCC was performed; the maximum was 11.47 mm3 with a mean of 2.40 mm3. Histological findings varied from the mere presence of AFCC to the formation of epithelialized granulation tissue. This granulation tissue was found in 19 of the bones. Theoretical clinical implications are considered for middle ear adhesions, otitis media and cholesteatoma.

Traumatic bronchial rupture

Traumatic injury to the tracheobronchial tree requires prompt, accurate diagnosis for optimum surgical treatment. The radiologist is in a pivotal position either to suggest this diagnosis or to initiate further investigation to establish it. Three cases of traumatic bronchial rupture illustrate the spectrum of radiologic findings and document the value of tomography in confirming this diagnosis.