The tympanic membrane displacement analyser for monitoring intracranial pressure in children

Abstract

PurposeRaised intracranial pressure (ICP) is a potentially treatable cause of morbidity and mortality but tools for monitoring are invasive. We sought to investigate the utility of the tympanic membrane displacement (TMD) analyser for non-invasive measurement of ICP in children.MethodsWe made TMD observations on normal and acutely comatose children presenting to Kilifi District Hospital (KDH) at the rural coast of Kenya and on children on follow-up for idiopathic intracranial hypertension at Evelina Children’s Hospital (ECH), in London, UK.ResultsWe recruited 63 patients (median age 3.3 (inter-quartile range (IQR) 2.0–4.3) years) at KDH and 14 children (median age 10 (IQR 5–11) years) at ECH. We observed significantly higher (more negative) TMD measurements in KDH children presenting with coma compared to normal children seen at the hospital’s outpatient department, in both semi-recumbent [mean −61.3 (95 % confidence interval (95 % CI) −93.5 to 29.1) nl versus mean −7.1 (95 % CI −54.0 to 68.3) nl, respectively; P = 0.03] and recumbent postures [mean −61.4 (95 % CI −93.4 to −29.3) nl, n = 59) versus mean −25.9 (95 % CI −71.4 to 123.2) nl, respectively; P = 0.03]. We also observed higher TMD measurements in ECH children with raised ICP measurements, as indicated by lumbar puncture manometry, compared to those with normal ICP, in both semi-recumbent [mean −259.3 (95 % CI −363.8 to −154.8) nl versus mean 26.7 (95 % CI −52.3 to 105.7) nl, respectively; P < 0.01] and recumbent postures [mean −137.5 (95 % CI −260.6 to −14.4) nl versus mean 96.6 (95 % CI 6.5 to 186.6) nl, respectively; P < 0.01].ConclusionThe TMD analyser has a potential utility in monitoring ICP in a variety of clinical circumstances.

Unexpected Relationship Between Tympanometry and Mortality in Children With Nontraumatic Coma

“…9 Thirty-eight (53%) had cerebral malaria (CM), 8 (11%) acute bacterial meningitis (ABM), 4 (6%) sepsis, and 22 (30%) encephalopathy of unknown etiology. Twenty (28%) children died during hospital stay, at a median time of 33 hours (IQR: 13-51 hours) from the time of admission.…”

“…10 In this brief report, we present our findings on the relationship between tympanometry and mortality among children with acute nontraumatic encephalopathy in a study whose primary objective was to explore the utility of the TMD analyzer for monitoring ICP. 9 …”

“…Thus, we have been interested in exploring the utility of tympanic membrane displacement (TMD) as a tool for noninvasive ICP monitoring. 9 The reliability of TMD analyzer measurements is dependent on normal middle ear function, which can be assessed by tympanometry.…”

“…9 The BCS is a simple score of coma status based on assessment of motor, verbal, and eyeopening ability, similar to the modified Glasgow and Adelaide coma scales but preferred in Africa because of its simplicity, specificity, and better interobserver agreement among health workers in this setting (Table 1). 11,12 After initial assessment at admission, the BCS was assessed every 4 hours by the attending clinicians.…”

Evaluation of a novel noninvasive ICP monitoring device in patients undergoing invasive ICP monitoring: preliminary results

“…24 When considering the disadvantages of I-ICP monitoring, it is understandable that efforts have been made to introduce an alternative measure that would allow for noninvasive ICP (NI-ICP) monitoring performed using surrogate parameters that correspond to the ICP but can be recorded from the outside of the skull. Of these techniques, transcranial Doppler ultrasonography, 32 tympanic membrane displacement, 12 and optic nerve sheath diameter (ONSD) 19 have been investigated. However, all methods have distinctive limitations that have prevented them from being used as replacements for invasive monitoring.…”