The Laryngoscope
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Case Report
Central Auditory Processing Deficiency With Anatomic Deficit in Left Superior Temporal Lobe Christopher R. Grindle, MD; Robert C. O’Reilly, MD; Thierry Morlet, PhD; Stephen Finden, MD
Objectives/Hypothesis: Describe the clinical presentation and treatment of a patient with central auditory processing deficiency associated with an anatomic deficit in the left superior temporal lobe. Study Design: Case report. Methods: We report a case and the treatment of an 8-year-old boy with abnormal speech development and auditory processing disorder who was found to have a large cystic lesion of his left superior temporal lobe. Results: An otherwise healthy 8-year old male presented to our department with a history of abnormal speech development. He began acquiring speech at a normal rate until 18 months of age, when he stopped speaking and reverted to unintelligible babbling. At approximately 3 years of age, he began to re-acquire speech at a normal rate, beginning where he had stopped 18 months earlier. Upon work-up, it was discovered that he had a 2.7 2.9 4.5 cm cystic lesion in the left Sylvian fissure with no associated soft tissue component. Findings were most consistent with arachnoid cyst. Central auditory processing testing was abnormal, particularly regarding the patient’s ability to manage competing auditory information. Conclusions: Central auditory processing disorders are a diverse group of disorders. Regardless of etiology, management focuses on modifying those
From the Department of Otolaryngology Head and Neck Surgery (C.R.G.), Department of Neuroradiology (S.F.), Thomas Jefferson University, Philadelphia, Pennsylvania; the Department of Otolaryngology–Head and Neck Surgery, Alfred I. duPont Hospital for Children, Wilmington, Delaware (R.C.O.); and the Center for Pediatric Auditory and Speech Sciences, Nemours Biomedical Research, Alfred I. duPont Hospital for Children, Wilmington, Delaware (T.M.). Editor’s Note: This Manuscript was accepted for publication February 25, 2010. Presented at the Triological Society Eastern Section Meeting, Philadelphia, Pennsylvania, U.S.A., January 25–27, 2008. The authors have no funding, financial relationships, or conflicts of interest to disclose. Send correspondence to Robert C. O’Reilly, MD, Department of Otolaryngology–Head and Neck Surgery, Alfred I. duPont Hospital for Children, P.O. Box 269, Wilmington, DE 19899. E-mail:
[email protected] DOI: 10.1002/lary.20986
Laryngoscope 120: August 2010
factors that most affect the individual in an attempt to enhance the access to auditory information. Key Words: Central auditory processing deficiency, arachnoid cyst. Laryngoscope, 120:1671–1674, 2010
CASE REPORT An otherwise healthy 8-year-old male, with no history of seizure or ear abnormalities, presented to our department with a history of abnormal speech development. The child began acquiring speech at a normal rate until 18 months of age, when he stopped speaking in short sentences and reverted to unintelligible babbling. At approximately 3 years of age he began to reacquire speech at a normal rate, beginning where he had stopped 18 months previously. No specific intervention was undertaken at that time because his mother believed his symptoms were the result of emotional problems. The patient had no history of otitis media and did not present for medical evaluation until he entered school, when it was noted that he had difficulties with reading and writing. Initial evaluation at 8 years of age included normal physical, otologic, and neurologic examinations. Tympanogram, middle ear muscle reflex thresholds, otoacoustic emissions, and pure-tone audiogram were all normal. Imaging of the patient was notable for the following: computed tomography (CT) without contrast was remarkable for a large deficit in the left superior temporal lobe consisting of a 2.7 2.9 4.5 cm cystic lesion in the left Sylvian fissure with no associated soft tissue component. These findings were most consistent with arachnoid cyst. A magnetic resonance image of the brain (Fig. 1) confirmed the CT findings, showing a left middle cranial fossa cystic lesion of cerebrospinal fluid intensity on all sequences (Fig. 2). The lesion did not enhance with contrast. An awake electroencephalogram was within normal limits without focal seizure activity. Grindle et al.: CAPD and Temporal Lobe Anatomic Defect
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Fig. 1. Sagittal T2 magnetic resonance imaging of the brain showing large cystic lesion in left superior temporal lobe. The arrows outline Broca’s area in the inferior frontal lobe.
Central auditory processing testing was performed and was abnormal (Table I). Some tests could not be administered due to the patient’s attention span and motivation on the specific days of testing. The number of tests successfully administered, however, allowed a final conclusion to be drawn on areas of strength and weakness of that particular case, and subsequent testing was not deemed necessary. The patient had poor performance in the left ear on the Competing Sentences Test, during which meaningful speech is presented to one ear while the contralateral ear receives a different, more intense message. Katz Staggered Spondaic Word Test was also abnormal. In this test, two bisyllabic words are presented in partially overlapping fashion. This test is sensitive for assessing the ability of the central auditory nervous system to contend with competing messages. The Competing Environmental Sound Test, which presents two environmental sounds simultaneously, one
Fig. 2. Sagittal T2 magnetic resonance imaging of the onstrating compression and deformity of the pars (Brodmann’s area 45) (straight arrow), and the pars (Brodmann’s area 44) (curved arrow). The anterior ramus is identified with an asterisk.
brain demtriangularis opercularis ascending
to each ear, was also significantly abnormal in the right ear and mildly abnormal in the left ear. Follow-up testing at 9 years and 9 months of age continued to demonstrate normal audiometry with type A tympanograms, normal otoacoustic emission, and normal pure-tone audiogram and speech reception thresholds. The patient again displayed abnormalities in tests of central auditory processing with below average scores on the Katz Staggered Spondaic Word Test. Additionally, his scores on the Competing Sentences Test remained below average, suggesting the patient’s difficulty with background noise, especially when primary messages were directed to his left ear. At 13 years of age, he is in the appropriate grade for his age (7th grade). His speech has continued to improve, he is answering questions appropriately, and has clear speech without dysarthria.
TABLE I. Central Auditory Processing Testing Results. Age at Test
7 Years 10 Months
8 Years 3 Months
9 Years 9 Months
Willeford Central Auditory Test battery Filtered speech Binaural Fusion Test
AD 62%, AS 42% AD 25%, AS 30% (nl 80%)
AD 80%, AS 95%
Alternating Speech Test
AD 70%, AS 70% (nl 90%)
95%
95%
Competing Sentences Test Katz Staggered Spondaic Word Test
AD 90%, AS 30% AD significantly abnormal, AS mildly abnormal AD normal, AS slightly abnormal
AD 95%, AS 6% AD below normal range, AS below normal range
AD 100%, AS 30% AD below normal range, AS below normal range
Pitch pattern sequencing
AD 100%, AS 90%
AD 100%, AS 100%
Wepman Auditory Memory Test Selective Auditory Attention Test
Above average memory span 92% without noise, 68% with noise
Competing Environmental Sound Test
AD 95%, AS 90%
AD ¼ right ear; AS ¼ left ear; nl ¼ normal.
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Fig. 3. (A) Sagittal T2 magnetic resonance imaging of the brain outlining the left Broca’s area with color overlays. The purple overlay defines the region of the pars triangularis and the green overlay defines the region of the pars opercularis. Note the compression and deformity of the brain parenchyma in Broca’s area. (B) The same regions are identified on the contralateral (right) side. Again, the purple overlay defines the region of the pars triangularis and the green overlay defines the region of the pars opercularis. [Color figure can be viewed in the online issue, which is available at www.interscience.wiley.com.]
To aid in the management of his central auditory processing deficits, with particular attention to his difficulty with competing messages, an individualized educational program has been developed for the patient. He currently has preferential classroom seating and he uses a frequency modulation (FM) system.
DISCUSSION Central auditory processing disorders are a diverse group of disorders that impair the individual’s ability to cognitively interpret and perceptually recognize the acoustic information that is presented through the auditory pathways, despite normal pure-tone hearing sensitivity in quiet. This includes sound localization, lateralization, auditory discrimination, pattern recognition, temporal resolution, integration, ordering, and auditory performance with degraded or competing sounds.1 Children with auditory processing disorders typically appear to be uncertain about what they hear in the presence of competing speech or background noise. As in the case of our patient, symptoms often manifest in early school years but might present in later years as classroom environments change and academic demands increase. Complaints might include difficulty staying on task, responding to complex instructions, and poor performance on memory tasks and tasks that require verbal language understanding rather than being hands on. The diagnosis of auditory processing disorders relies upon a battery of tests that evaluate the function of the central auditory nervous system and determine the type of deficiency. Tests are both behavioral and electrophysiologic and incorporate variances in frequency, temporal presentation, and intensity. In a particular child, one or several of these processes can be affected. The diagnosis requires a multidisciplinary approach with attention to cognitive, memory, and linguistic parameters.2 In this Laryngoscope 120: August 2010
particular case, the auditory performance with degraded or competing sounds remains notably abnormally low over time. It is, however, almost impossible to identify precisely which brain mechanism is responsible for this decreased performance. In our patient, work-up revealed a left temporal lobe lesion consistent with an arachnoid cyst. These are rare, congenital intracranial space-occupying lesions with males affected in two thirds of cases. They are predominately asymptomatic, although they might occasionally enlarge and become symptomatic due to compression of adjacent neural structures. In some cases, there might be an underdevelopment of the surrounding cerebral cortex, particularly in the temporal lobe as seen in our case (Fig. 2).3 The lesion in our patient likely affected development of speech and language abilities, and compensation would depend on the plasticity of the developing brain. Thus, the language centers would have to undergo either interhemispheric or ipsilateral reorganization. Relevant to our case, as can be seen in the images in Figure 3, there is a rightward asymmetry to Broca’s area (including the pars triangularis and the pars opercularis). This might indicate that there has been shift in language centers, as it has been suggested that asymmetries in portions of Broca’s area might predict language dominance.4 Left hemispherectomy observed immediately after birth results in language development in the right hemisphere.5 Review of recent articles published on functional neuroimaging used in the recovery of patients with aphasia after stroke showed no definitive evidence of consistent left- or right-sided activation or reorganization. Rather, both hemispheres might be involved based on site of injury and duration and extent of recovery.6 Other studies, however, have shown limited evidence of laterality shift in patients recovering from aphasia7 and in patients with left hemispheric arachnoid cysts.8 In Grindle et al.: CAPD and Temporal Lobe Anatomic Defect
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one study, both the patient group and the control group showed left posterior temporal lobe activation on positron emission tomography testing with no significant activation of the right hemisphere.8 In our patient, it is unknown which hemisphere, if any, underwent reorganization; however, the clinical history suggests that he acquired language at a normal rate in his first 18 months until he reached the capacity of his hypoplastic left temporal area. The subsequent 18 months of no language development could have been the time used for reorganization of his language centers, allowing for reacquisition of language.
CONCLUSION Central auditory processing disorders are a diverse group of disorders that reduce an individual’s ability to interpret and organize the acoustic information that is presented through the auditory pathways. Our case illustrates the importance of searching for central nervous system structural lesions in patients presenting with atypical symptoms and history. Regardless of etiology, management of auditory processing disorders focuses on modifying those environmental and external factors that most affect the individual to enhance the access to auditory information. Such strategies include signal enhancement, such as FM systems, vocabulary building, and formal auditory training
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in compensatory strategies to overcome deficiencies and make maximum use of auditory information provided.
BIBLIOGRAPHY 1. Palfery TD, Duff D. Central auditory processing disorders: review and case study. Axone 2007;28:20–23. 2. Bamiou DE, Musiek FE, Luxon LM. Aetiology and clinical presentations of auditory processing disorders—a review. Arch Dis Child 2001;85:361–365. 3. Gosalakkal JA. Intracranial arachnoid cysts in children: a review of pathogenesis, clinical features, and management. Pediatr Neurol 2002;26:93–98. 4. Foundas AL, Eure KF, Luevano LF, Weinberger DR. MRI asymmetries of Broca’s area: the pars triangularis and pars opercularis. Brain Lang 1998;64:282–296. 5. Mariotti P, Iuvone L, Torrioli MG, Silveri MC. Linguistic and non-linguistic abilities in a patient with early left hemispherectomy. Neuropsychologia 1998;36:1303–1312. 6. Crinion JT, Leff AP. Recovery and treatment of aphasia after stroke: functional imaging studies. Curr Opin Neurol 2007;20:667–673. 7. Warburton E, Price CJ, Swinburn K, Wise RJ. Mechanisms of recovery from aphasia: evidence from positron emission tomography studies. J Neurol Neurosurg Psychiatry 1999; 66:155–161. 8. Stowe LA, Go KG, Pruim J, den Dunnen W, Meiners LC, Paans AM. Language localization in cases of left temporal lobe arachnoid cyst: evidence against interhemispheric reorganization. Brain Lang 2000;75:347– 358.
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