Otology & Neurotology 35:1742Y1745 Ó 2014, Otology & Neurotology, Inc.
Case Report: Cochlear Implantation in a Patient With Superficial Siderosis *Michelle Ryan, *Doris Piplica, and *†‡Ming Zhang *Department of Audiology, Alberta Health ServicesYGlenrose Rehabilitation Hospital; ÞDepartment of Speech Pathology and Audiology, University of AlbertaYFaculty of Rehabilitation Medicine; and þDepartment of SurgeryYOtolaryngology, University of AlbertaYFaculty of Medicine and Dentistry, Edmonton, Canada
Objective: This is a retrospective case review study. Current understanding of cochlear implantation in patients with superficial siderosis is limited, with roughly 15 reported cases worldwide. The purpose of this study is to report an additional case of cochlear implantation in a patient with superficial siderosis and to contribute to the current literature available on outcomes of implantation in these individuals. Patients: One cochlear implant user with superficial siderosis in a tertiary referral center. Intervention(s): Therapeutic and rehabilitative. Main Outcome and Results: Open set speech perception word scores increased from 0% preimplantation with bilateral hearing aids to 8% postimplantation in the bimodal condition (cochlear implant in the left ear and hearing aid in the right ear). Phoneme scores increased from 16% preimplantation to 36% postimplantation. The patient also demonstrated improvement from 38% preimplantation to 83% postimplantation on a closed set word test. Performance on open set recorded sentences did not
improve; however, open set sentences administered live voice revealed an increase in performance from 4% preimplantation to 25% postimplantation in the auditory only condition and from 59% to 86% in the auditory-visual condition. Conclusion: For this patient with superficial siderosis, only marginal improvements in test scores at 11 months postimplantation were seen. Minimally, the use of a cochlear implant did prevent further deterioration of auditory performance. Therefore, patients with superficial siderosis who choose to proceed with cochlear implantation may still report perceived benefit from the maintenance of speech perception abilities even in the presence of minimal improvement. Rapid deterioration in hearing thresholds and speech discrimination before implantation may be an indicator of an actively progressing case of superficial siderosis, which may suggest possible limited benefit from cochlear implantation. Key Words: Cochlear implantationVHearing lossVSuperficial siderosis. Otol Neurotol 35:1742Y1745, 2014.
Superfical siderosis is a rare, progressive disease of the central nervous system. Superficial siderosis is understood to be a result of chronic bleeding in the subarachnoid space (1). There is an accumulation of hemosiderin and, subsequently, a buildup of excessive free iron in the leptomeninges, subpial tissue, spinal cord, and cranial nerves (2Y5). Hemorrhaging in the subarachnoid space may be a result of trauma or neurosurgery but remains unidentified in roughly 50% of cases of superficial siderosis (2,6). The disproportionate free iron results in demyelination and cell loss (5,7,8).
Hearing loss is often an early symptom of superfical siderosis, with progressive sensorineural hearing loss seen in 95% of patients (1,2). In addition, many patients (88%) will also present with ataxia and, to a lesser degree, may demonstrate additional complications including pyramidal signs, dementia, and other sensory signs (1,9). Individuals with hearing impairment require audiologic service to maintain and improve communication and speech perception. The principal treatment for bilateral sensorineural hearing loss is traditional amplification (hearing aids) or cochlear implantation (CI) if more severe. There are at least 15 cases reported in the literature of patients with superfical siderosis who have undergone CI, the outcomes of which have been quite variable (5). Some cases have shown very little or no benefit from the CI, and in some cases, there has been discontinuation or limited use of the device (5,6). For other patients (47%), there is evidence that CI can provide significant benefit (5,8,10).
Address correspondence and reprint requests to Ming Zhang, M.D., Ph.D., University of Alberta (Faculty of Rehabilitation Medicine), Department of Speech Pathology and Audiology, 8205 114th Street (2-70 Corbett Hall), Edmonton, AB T6G 2G4, Canada; E-mail: ming.zhang@ ualberta.ca The authors disclose no conflicts of interest. Supplemental digital content is available in the text.
1742
Copyright © 2014 Otology & Neurotology, Inc. Unauthorized reproduction of this article is prohibited.
COCHLEAR IMPLANTATION AND SUPERFICIAL SIDEROSIS
1743
From a clinical perspective, CI benefit is typically measured by comparing preimplantation audiometric hearing thresholds and speech perception test scores to postimplantation performance on these same tests. In cases where a patient shows no improvement in speech perception performance postimplantation, the clinician and patient may be able to define benefit in more subjective terms. Recent publications have suggested that more evidence is needed to illustrate the range of possible outcomes in CI for patients with superficial siderosis and to address the clinical issues when considering CI as a treatment option for hearing loss in these patients (5,11). We report here on a clinical case of a patient with superficial siderosis who underwent CI as a treatment for severe-toprofound sensorineural hearing loss.
CASE REPORT This section is posted online (Supplemental Digital Content, http://links.lww.com/MAO/A244).
DISCUSSION
FIG. 1. Preimplantation audiometric hearing sensitivity. Progression of hearing sensitivity over time from March 2008 to February 2012 in the left (A) ear and right (B) ear.
As superficial siderosis can be destructive both peripherally and centrally, the decision to proceed with CI in this population requires careful consideration during the assessment process, and comprehensive counseling is vital to preparing the patient for possible limited benefit or deterioration of benefit over time (5,6,10). The variability in patient benefit from CI in cases of superficial siderosis may depend on the site of lesion, the cochlear nerve function, and/or how active the neural degeneration process is within an individual patient (5). TABLE 1. Speech perception test CNC Words CNC Phonemes AZ Bio Sentences CID Sentences Yauditory only CID Sentences Yauditory+visual
This case report provides supporting evidence that patients who demonstrate active progression of their hearing sensitivity or progression in other symptoms as a result of superficial siderosis may show limited benefit from CI (5). The patient reported here clearly demonstrated active progression of the disease, given the rapid deterioration of hearing thresholds before surgery (Fig. 1), as well as postsurgery in the nonimplanted ear. Development and worsening of other neurologic symptoms was also evidenced over a 4-year period. The patient was able to maintain the speech perception ability that was present preimplant (Table 1). The nonimplant (right) ear showed further deterioration in speech perception ability and hearing thresholds over time. This suggests that without implantation, the left ear would have likely demonstrated further deterioration as well, rather than the maintenance observed. In the case of the closed set word tests, the patient’s performance did suggest some improvement based on the scores obtained on the spondee identification and monosyllabic identification tasks at 11 months postimplantation
Open set speech perception test results before and after implantation
Preimplant Preimplant Preimplant bilateral 6 months after 11 months after left HA (%) right HA (%) amplification (%) left CI (%) left CI (%) 4 20
0 16
0 16 5 4
4 19 0 17
0 33 0 25
59
64
86
11 months after right HA (%)
11 months after left CI + right HA (%)
0 0
8 36 0
HA indicates hearing aid; CI, cochlear implant. Otology & Neurotology, Vol. 35, No. 10, 2014
Copyright © 2014 Otology & Neurotology, Inc. Unauthorized reproduction of this article is prohibited.
1744
M. RYAN ET AL. TABLE 2.
Speech perception test ESPYpattern perception ESPYspondee identification ESPYmonosyllabic identification
Closed set speech perception test results before and after implantation
Preimplant left HA (%)
Preimplant right HA (%)
3 months after left CI (%)
6 months after left CI (%)
11 months after left CI (%)
100 38 38
71 21 21
92 96 54
92 67 46
100 83 83
HA indicates hearing aid; CI, cochlear implant.
(Table 2). Although benefit was marginal, this evidence supports the decision to proceed with CI in this individual. This case suggests that implantation may potentially affect multiple neural components in parallel across a tonotopical range of frequencies. When one considers the patient’s ability to purely perceive the presence of sound, there is an improvement seen postimplantation (Fig. 2). As progression in hearing thresholds was noted postimplantation in the nonimplant (right) ear, it is likely that progression of hearing thresholds will continue for this patient; however, the CI maintains the ability to detect these sounds in the left ear, at least for the time being. The programming of the device proved challenging in this case. Our case is consistent with other superficial siderosis cases where, because of substantial damage of the neural components, conventional objective assessments may not be successful. For example, neural response imaging and electrically evoked stapedius reflex threshold measures were unsuccessful at eliciting a neural response. The neurologic degenerative nature of the patient’s disorder likely predicted and accounts for the inability to use electrophysiologic measures that are dependent on neural integrity to assist in cochlear implant programming. As such, subjective responses were determined to be most valuable in programming this patient. Multiple changes to the program settings of the CI were made in an attempt to enhance the patient’s speech perception ability and to improve sound quality. A more simple processing strategy was shown to be preferred by the patient, and likely results in less demand on the compromised neural system. The limited benefit that has been shown on the speech perception tests postimplantation could possibly be a result of some minor amount of plasticity in the auditory system, which has allowed the patient to adapt to the CI signal. Whether this benefit can be maintained, or whether the patient experiences adverse effects from electrical stimulation in the future, similar to that described by Wood et al. (6) in their report, remains to be seen. This report also supports the principle previously discussed by several authors that a thorough assessment and counseling process is imperative when considering CI in patients with superficial siderosis (5,6,10). By counseling and preparing a patient for what could be a disappointing result, the patient can make an informed decision of whether to proceed. Even in the presence of contraindications such as a probable compromised central auditory system, there may still be measureable benefit
(5). In addition, there may still be perceived benefit from the patient’s perspective, even when there is no measureable benefit. For example, the ability to maintain function or prevent further deterioration for a period may in fact be a benefit of CI in these patients. When seen in the clinic for follow-up, the patient reported that he was grateful to have received the implant. He reported that his ability to have a one-on-one casual conversation had slightly improved, as well as his understanding of both men and women’s voices and his awareness of environmental sounds. However, he noted that his speech understanding in noise had remained unchanged, and he was unable to use the telephone and enjoy music. When asked directly, the patient reported ‘‘no regrets’’ in his choice to proceed with CI. Although careful assessment and counseling was critical in this case, generalizing this approach to cases of all patients presenting with other known neurologic diseases is suggested. When working with a patient who has a compromised neurologic system, regardless of the underlying diagnosis, it is likely best for the clinician to proceed with caution and counsel appropriately. A qualitative benefit measure, such as a quality-of-life scale, may be beneficial clinically in cases where it is expected that traditional testing methods, such as speech perception testing, may demonstrate limited or no benefit. The patient’s report of benefit in this case has supported the continued use of the device when only minimal measureable benefit has been seen. Finally, it is still worth emphasizing the rapid progressive nature of superficial siderosis in this case. Similar to those circumstances described by Tyler et al (5),
FIG. 2. Hearing detection after initial CI stimulation. Hearing detection in soundfield with left cochlear implant after initial stimulation (3Y11 mo postoperatively).
Otology & Neurotology, Vol. 35, No. 10, 2014
Copyright © 2014 Otology & Neurotology, Inc. Unauthorized reproduction of this article is prohibited.
COCHLEAR IMPLANTATION AND SUPERFICIAL SIDEROSIS our patient demonstrated rapid deterioration of both balance function and hearing sensitivity before implantation, which was likely an indicator that the patient’s superficial siderosis was in an active state. The results of this study suggest that, although active deterioration of function due to superficial siderosis is an indicator of limited benefit of implantation, this does not preclude attempting CI if the patient is fully informed and prepared for the range of possible outcomes. Success of implantation in this population may not be demonstrated by speech perception scores but by the perceived benefit from the patient’s perspective. Some cases have shown that benefit can be maintained for up to 7 years postimplantation (11). Conversely, it has also been shown that deterioration in benefit can occur quite rapidly and can result in the discontinuation of device use (6). This patient was satisfied with his CI and continues to wear the device all waking hours. He has considered maintaining his limited speech perception to be a successful outcome, although how long he will experience this preservation of speech perception function is unknown. Acknowledgment: The authors thank the participants of this study who consented to the publishing of their findings for the purposes of contributing to the body of knowledge regarding cochlear implantation in patients with superficial siderosis.
1745
REFERENCES 1. Fearnley J, Stevens J, Rudge P. Superficial siderosis of the central nervous system. Brain 1995;118:1051Y66. 2. Sugimoto H, Ito M, Hatano M, Yoshizaki T. Cochlear implantation in a patient with superficial siderosis. Auris Nasus Larynx 2012;39:623Y6. 3. Dhooge I, De Vel E, Urgell H, Gallego S, Vinck B. Cochlear implantation in a patient with superficial siderosis of the central nervous system. Otol Neurotol 2002;23:468Y72. 4. Irving R, Graham J. Cochlear implantation in superficial siderosis. J Laryngol Otol 1996;110:1151Y3. 5. Tyler G, Martin T, Baguley D. Systematic review of outcome of cochlear implantation in superficial siderosis. Otol Neurotol 2012; 33:976Y82. 6. Wood V, Bird P, Giles E, Baber W. Unsuccessful cochlear implantation in two patients with superficial siderosis of the central nervous system. Otol Neurotol 2008;29:622Y5. 7. Sydlowski S, Cevette M, Shallop J, Barrs D. Cochlear implant patients with superficial siderosis. J Am Acad Audiol 2009;20: 348Y52. 8. Hathaway B, Hirsch B, Branstetter B. Successful cochlear implantation in a patient with superficial siderosis. Am J Otolaryngol Head Neck Med Surg 2006;27:255Y8. 9. Nadol J, Adams J, O’Malley J. Temporal bone histopathology in a case of sensorineural hearing loss caused by superficial siderosis of the central nervous system and treated by cochlear implantation. Otol Neurotol 2011;32:748Y55. 10. Nogueira C, Meehan T. Successful outcome of cochlear implantation in a patient with superficial siderosis. B-Ent 2012;8:57Y9. 11. Grover N, Whiteside O, Ramsden J. Cochlear implantation in superficial siderosis-a viable option? Cochlear Implants Int 2011; 12:241Y3.
Otology & Neurotology, Vol. 35, No. 10, 2014
Copyright © 2014 Otology & Neurotology, Inc. Unauthorized reproduction of this article is prohibited.
Case Report: Cochlear Implantation in a Patient With Superficial Siderosis *Michelle Ryan, *Doris Piplica, and *†‡Ming Zhang *Department of Audiology, Alberta Health ServicesYGlenrose Rehabilitation Hospital; ÞDepartment of Speech Pathology and Audiology, University of AlbertaYFaculty of Rehabilitation Medicine; and þDepartment of SurgeryYOtolaryngology, University of AlbertaYFaculty of Medicine and Dentistry, Edmonton, Canada
Objective: This is a retrospective case review study. Current understanding of cochlear implantation in patients with superficial siderosis is limited, with roughly 15 reported cases worldwide. The purpose of this study is to report an additional case of cochlear implantation in a patient with superficial siderosis and to contribute to the current literature available on outcomes of implantation in these individuals. Patients: One cochlear implant user with superficial siderosis in a tertiary referral center. Intervention(s): Therapeutic and rehabilitative. Main Outcome and Results: Open set speech perception word scores increased from 0% preimplantation with bilateral hearing aids to 8% postimplantation in the bimodal condition (cochlear implant in the left ear and hearing aid in the right ear). Phoneme scores increased from 16% preimplantation to 36% postimplantation. The patient also demonstrated improvement from 38% preimplantation to 83% postimplantation on a closed set word test. Performance on open set recorded sentences did not
improve; however, open set sentences administered live voice revealed an increase in performance from 4% preimplantation to 25% postimplantation in the auditory only condition and from 59% to 86% in the auditory-visual condition. Conclusion: For this patient with superficial siderosis, only marginal improvements in test scores at 11 months postimplantation were seen. Minimally, the use of a cochlear implant did prevent further deterioration of auditory performance. Therefore, patients with superficial siderosis who choose to proceed with cochlear implantation may still report perceived benefit from the maintenance of speech perception abilities even in the presence of minimal improvement. Rapid deterioration in hearing thresholds and speech discrimination before implantation may be an indicator of an actively progressing case of superficial siderosis, which may suggest possible limited benefit from cochlear implantation. Key Words: Cochlear implantationVHearing lossVSuperficial siderosis. Otol Neurotol 35:1742Y1745, 2014.
Superfical siderosis is a rare, progressive disease of the central nervous system. Superficial siderosis is understood to be a result of chronic bleeding in the subarachnoid space (1). There is an accumulation of hemosiderin and, subsequently, a buildup of excessive free iron in the leptomeninges, subpial tissue, spinal cord, and cranial nerves (2Y5). Hemorrhaging in the subarachnoid space may be a result of trauma or neurosurgery but remains unidentified in roughly 50% of cases of superficial siderosis (2,6). The disproportionate free iron results in demyelination and cell loss (5,7,8).
Hearing loss is often an early symptom of superfical siderosis, with progressive sensorineural hearing loss seen in 95% of patients (1,2). In addition, many patients (88%) will also present with ataxia and, to a lesser degree, may demonstrate additional complications including pyramidal signs, dementia, and other sensory signs (1,9). Individuals with hearing impairment require audiologic service to maintain and improve communication and speech perception. The principal treatment for bilateral sensorineural hearing loss is traditional amplification (hearing aids) or cochlear implantation (CI) if more severe. There are at least 15 cases reported in the literature of patients with superfical siderosis who have undergone CI, the outcomes of which have been quite variable (5). Some cases have shown very little or no benefit from the CI, and in some cases, there has been discontinuation or limited use of the device (5,6). For other patients (47%), there is evidence that CI can provide significant benefit (5,8,10).
Address correspondence and reprint requests to Ming Zhang, M.D., Ph.D., University of Alberta (Faculty of Rehabilitation Medicine), Department of Speech Pathology and Audiology, 8205 114th Street (2-70 Corbett Hall), Edmonton, AB T6G 2G4, Canada; E-mail: ming.zhang@ ualberta.ca The authors disclose no conflicts of interest. Supplemental digital content is available in the text.
1742
Copyright © 2014 Otology & Neurotology, Inc. Unauthorized reproduction of this article is prohibited.
COCHLEAR IMPLANTATION AND SUPERFICIAL SIDEROSIS
1743
From a clinical perspective, CI benefit is typically measured by comparing preimplantation audiometric hearing thresholds and speech perception test scores to postimplantation performance on these same tests. In cases where a patient shows no improvement in speech perception performance postimplantation, the clinician and patient may be able to define benefit in more subjective terms. Recent publications have suggested that more evidence is needed to illustrate the range of possible outcomes in CI for patients with superficial siderosis and to address the clinical issues when considering CI as a treatment option for hearing loss in these patients (5,11). We report here on a clinical case of a patient with superficial siderosis who underwent CI as a treatment for severe-toprofound sensorineural hearing loss.
CASE REPORT This section is posted online (Supplemental Digital Content, http://links.lww.com/MAO/A244).
DISCUSSION
FIG. 1. Preimplantation audiometric hearing sensitivity. Progression of hearing sensitivity over time from March 2008 to February 2012 in the left (A) ear and right (B) ear.
As superficial siderosis can be destructive both peripherally and centrally, the decision to proceed with CI in this population requires careful consideration during the assessment process, and comprehensive counseling is vital to preparing the patient for possible limited benefit or deterioration of benefit over time (5,6,10). The variability in patient benefit from CI in cases of superficial siderosis may depend on the site of lesion, the cochlear nerve function, and/or how active the neural degeneration process is within an individual patient (5). TABLE 1. Speech perception test CNC Words CNC Phonemes AZ Bio Sentences CID Sentences Yauditory only CID Sentences Yauditory+visual
This case report provides supporting evidence that patients who demonstrate active progression of their hearing sensitivity or progression in other symptoms as a result of superficial siderosis may show limited benefit from CI (5). The patient reported here clearly demonstrated active progression of the disease, given the rapid deterioration of hearing thresholds before surgery (Fig. 1), as well as postsurgery in the nonimplanted ear. Development and worsening of other neurologic symptoms was also evidenced over a 4-year period. The patient was able to maintain the speech perception ability that was present preimplant (Table 1). The nonimplant (right) ear showed further deterioration in speech perception ability and hearing thresholds over time. This suggests that without implantation, the left ear would have likely demonstrated further deterioration as well, rather than the maintenance observed. In the case of the closed set word tests, the patient’s performance did suggest some improvement based on the scores obtained on the spondee identification and monosyllabic identification tasks at 11 months postimplantation
Open set speech perception test results before and after implantation
Preimplant Preimplant Preimplant bilateral 6 months after 11 months after left HA (%) right HA (%) amplification (%) left CI (%) left CI (%) 4 20
0 16
0 16 5 4
4 19 0 17
0 33 0 25
59
64
86
11 months after right HA (%)
11 months after left CI + right HA (%)
0 0
8 36 0
HA indicates hearing aid; CI, cochlear implant. Otology & Neurotology, Vol. 35, No. 10, 2014
Copyright © 2014 Otology & Neurotology, Inc. Unauthorized reproduction of this article is prohibited.
1744
M. RYAN ET AL. TABLE 2.
Speech perception test ESPYpattern perception ESPYspondee identification ESPYmonosyllabic identification
Closed set speech perception test results before and after implantation
Preimplant left HA (%)
Preimplant right HA (%)
3 months after left CI (%)
6 months after left CI (%)
11 months after left CI (%)
100 38 38
71 21 21
92 96 54
92 67 46
100 83 83
HA indicates hearing aid; CI, cochlear implant.
(Table 2). Although benefit was marginal, this evidence supports the decision to proceed with CI in this individual. This case suggests that implantation may potentially affect multiple neural components in parallel across a tonotopical range of frequencies. When one considers the patient’s ability to purely perceive the presence of sound, there is an improvement seen postimplantation (Fig. 2). As progression in hearing thresholds was noted postimplantation in the nonimplant (right) ear, it is likely that progression of hearing thresholds will continue for this patient; however, the CI maintains the ability to detect these sounds in the left ear, at least for the time being. The programming of the device proved challenging in this case. Our case is consistent with other superficial siderosis cases where, because of substantial damage of the neural components, conventional objective assessments may not be successful. For example, neural response imaging and electrically evoked stapedius reflex threshold measures were unsuccessful at eliciting a neural response. The neurologic degenerative nature of the patient’s disorder likely predicted and accounts for the inability to use electrophysiologic measures that are dependent on neural integrity to assist in cochlear implant programming. As such, subjective responses were determined to be most valuable in programming this patient. Multiple changes to the program settings of the CI were made in an attempt to enhance the patient’s speech perception ability and to improve sound quality. A more simple processing strategy was shown to be preferred by the patient, and likely results in less demand on the compromised neural system. The limited benefit that has been shown on the speech perception tests postimplantation could possibly be a result of some minor amount of plasticity in the auditory system, which has allowed the patient to adapt to the CI signal. Whether this benefit can be maintained, or whether the patient experiences adverse effects from electrical stimulation in the future, similar to that described by Wood et al. (6) in their report, remains to be seen. This report also supports the principle previously discussed by several authors that a thorough assessment and counseling process is imperative when considering CI in patients with superficial siderosis (5,6,10). By counseling and preparing a patient for what could be a disappointing result, the patient can make an informed decision of whether to proceed. Even in the presence of contraindications such as a probable compromised central auditory system, there may still be measureable benefit
(5). In addition, there may still be perceived benefit from the patient’s perspective, even when there is no measureable benefit. For example, the ability to maintain function or prevent further deterioration for a period may in fact be a benefit of CI in these patients. When seen in the clinic for follow-up, the patient reported that he was grateful to have received the implant. He reported that his ability to have a one-on-one casual conversation had slightly improved, as well as his understanding of both men and women’s voices and his awareness of environmental sounds. However, he noted that his speech understanding in noise had remained unchanged, and he was unable to use the telephone and enjoy music. When asked directly, the patient reported ‘‘no regrets’’ in his choice to proceed with CI. Although careful assessment and counseling was critical in this case, generalizing this approach to cases of all patients presenting with other known neurologic diseases is suggested. When working with a patient who has a compromised neurologic system, regardless of the underlying diagnosis, it is likely best for the clinician to proceed with caution and counsel appropriately. A qualitative benefit measure, such as a quality-of-life scale, may be beneficial clinically in cases where it is expected that traditional testing methods, such as speech perception testing, may demonstrate limited or no benefit. The patient’s report of benefit in this case has supported the continued use of the device when only minimal measureable benefit has been seen. Finally, it is still worth emphasizing the rapid progressive nature of superficial siderosis in this case. Similar to those circumstances described by Tyler et al (5),
FIG. 2. Hearing detection after initial CI stimulation. Hearing detection in soundfield with left cochlear implant after initial stimulation (3Y11 mo postoperatively).
Otology & Neurotology, Vol. 35, No. 10, 2014
Copyright © 2014 Otology & Neurotology, Inc. Unauthorized reproduction of this article is prohibited.
COCHLEAR IMPLANTATION AND SUPERFICIAL SIDEROSIS our patient demonstrated rapid deterioration of both balance function and hearing sensitivity before implantation, which was likely an indicator that the patient’s superficial siderosis was in an active state. The results of this study suggest that, although active deterioration of function due to superficial siderosis is an indicator of limited benefit of implantation, this does not preclude attempting CI if the patient is fully informed and prepared for the range of possible outcomes. Success of implantation in this population may not be demonstrated by speech perception scores but by the perceived benefit from the patient’s perspective. Some cases have shown that benefit can be maintained for up to 7 years postimplantation (11). Conversely, it has also been shown that deterioration in benefit can occur quite rapidly and can result in the discontinuation of device use (6). This patient was satisfied with his CI and continues to wear the device all waking hours. He has considered maintaining his limited speech perception to be a successful outcome, although how long he will experience this preservation of speech perception function is unknown. Acknowledgment: The authors thank the participants of this study who consented to the publishing of their findings for the purposes of contributing to the body of knowledge regarding cochlear implantation in patients with superficial siderosis.
1745
REFERENCES 1. Fearnley J, Stevens J, Rudge P. Superficial siderosis of the central nervous system. Brain 1995;118:1051Y66. 2. Sugimoto H, Ito M, Hatano M, Yoshizaki T. Cochlear implantation in a patient with superficial siderosis. Auris Nasus Larynx 2012;39:623Y6. 3. Dhooge I, De Vel E, Urgell H, Gallego S, Vinck B. Cochlear implantation in a patient with superficial siderosis of the central nervous system. Otol Neurotol 2002;23:468Y72. 4. Irving R, Graham J. Cochlear implantation in superficial siderosis. J Laryngol Otol 1996;110:1151Y3. 5. Tyler G, Martin T, Baguley D. Systematic review of outcome of cochlear implantation in superficial siderosis. Otol Neurotol 2012; 33:976Y82. 6. Wood V, Bird P, Giles E, Baber W. Unsuccessful cochlear implantation in two patients with superficial siderosis of the central nervous system. Otol Neurotol 2008;29:622Y5. 7. Sydlowski S, Cevette M, Shallop J, Barrs D. Cochlear implant patients with superficial siderosis. J Am Acad Audiol 2009;20: 348Y52. 8. Hathaway B, Hirsch B, Branstetter B. Successful cochlear implantation in a patient with superficial siderosis. Am J Otolaryngol Head Neck Med Surg 2006;27:255Y8. 9. Nadol J, Adams J, O’Malley J. Temporal bone histopathology in a case of sensorineural hearing loss caused by superficial siderosis of the central nervous system and treated by cochlear implantation. Otol Neurotol 2011;32:748Y55. 10. Nogueira C, Meehan T. Successful outcome of cochlear implantation in a patient with superficial siderosis. B-Ent 2012;8:57Y9. 11. Grover N, Whiteside O, Ramsden J. Cochlear implantation in superficial siderosis-a viable option? Cochlear Implants Int 2011; 12:241Y3.
Otology & Neurotology, Vol. 35, No. 10, 2014
Copyright © 2014 Otology & Neurotology, Inc. Unauthorized reproduction of this article is prohibited.
