Long-term status of middle-ear aeration post canal wall down mastoidectomy.

BACKGROUND: Retraction pocket theory is the most acceptable theory for cholesteatoma formation. Canal wall down mastoidectomy is widely performed for cholesteatoma removal. Post-operatively, each patient with canal wall down mastoidectomy has an exteriorised mastoid cavity, exteriorised attic, neo-tympanic membrane and shallow neo-middle ear. OBJECTIVE: This study aimed to clinically assess the status of the neo-tympanic membrane and the exteriorised attic following canal wall down mastoidectomy. METHODS: All post canal wall down mastoidectomy patients were recruited and otoendoscopy was performed to assess the neo-tympanic membrane. A clinical classification of the overall status of middle-ear aeration following canal wall down mastoidectomy was formulated. RESULTS: Twenty-five ears were included in the study. Ninety-two per cent of cases showed some degree of neo-tympanic membrane retraction, ranging from mild to very severe. CONCLUSION: After more than six months following canal wall down mastoidectomy, the degree of retracted neo-tympanic membranes and exteriorised attics was significant. Eustachian tube dysfunction leading to negative middle-ear aeration was present even after the canal wall down procedure. However, there was no development of cholesteatoma, despite persistent retraction.

Surgical outcome of bone anchored hearing aid (baha) implant surgery: a 10 years experience.

Bone anchored hearing aid (Baha) implant is an option for patient with canal atresia, single sided deafness(SSD) and chronically discharging ears despite treatments. This retrospective study was conducted from 2001 to 2011 to evaluate the surgical outcome of Baha implant surgery. Thirty-three patients were identified during this study period. Their age at implantation ranged from 5 to 40 years. Of 33 patients, 29 (87.9 %) patients had bilateral microtia and canal atresia, 3 (9.1 %) patients had unilateral microtia and canal atresia and 1 (3.0 %) patients have SSD following labyrinthitis. One patient (3.2 %) had major complication which is lost of implant due to failure of osseointegration. Soft tissue reactions were seen 7 patients (21.1 %). Of these 7 patients, 4 patients required 3-4 procedures as day care operation for excision of the skin overgrowth surrounding the abutment. Recurrent antibiotic treatment was required in 3 patients (9.7 %). None of our patient had history of intraoperative or peri-operative complication following Baha surgery. The commonest complications are local infection and inflammation at the implant site. None of our patient had history of intraoperative or peri-operative complication following Baha implant surgery.

The association between GJB2 mutation and GJB6 gene in non syndromic hearing loss school children.

Recently, molecular testing for GJB2 mutations has become the standard of care for the diagnosis of patients with non syndromic hearing impairment of unknown cause. The aims of this study are to determine the association between GJB2 mutation and GJB6 and to report the variation of mutations in deaf students who have heterozygous GJB2. This retrospective study was conducted at Universiti Kebangsaan Malaysia Medical Center (UKMMC). Data was collected from previous files and records from Tissue Engineering and Human Genetic Research Group Laboratory. Approval from Ethical Committee was obtained prior to the study. A total of 138 students have been screened in previous studies in UKMMC for the presence of GJB2 mutations as a cause for hearing loss. Thirty four of the 138 subjects have GJB2 mutations; 2 showed homozygous mutations whereas another 32 were heterozygous for GJB2 gene mutation. Only 31 DNA samples of students presented with sensorineural hearing loss with heterozygous mutation in GJB2 gene were included in this study. The sequencing results obtained were analyzed. The degree of hearing loss of those students with association between GJB2 mutation and GJB6 mutation will be discussed. Five out of 31 subjects (16.2%) have mutations in their GJB6 gene, suggesting a digenic inheritance of GJB2/GJB6 mutation. In total, four novel mutations were identified; E137D (n=1), R32Q (n=1), E101K (n=1) and Y156H (n=1) and one mutation deletion; 366delT (n=1). All students with association GJB2 mutation and GJB6 showed severe to profound hearing loss in both ears. Interestingly this study not detected the large deletion of 342 kb in GJB6 gene suggesting that the mutation is very rare in this region compared to certain parts of the world.

Cholesteatoma in patients with congenital external auditory canal anomalies: retrospective review.

OBJECTIVE: To review cases of congenital external auditory canal anomaly with cholesteatoma, documenting clinical presentation, cholesteatoma site and extent, complications, and surgery. METHOD: Retrospective review of all cases of congenital canal anomaly with cholesteatoma treated between 1998 and 2009. RESULTS: Of 41 cases with canal anomalies, 17 (43.9 per cent) had associated cholesteatoma. Medical records were unretrievable for four cases. Of the remaining 13 patients (five females and eight males, age range four to 73 years, mean 21 years), 10 presented chiefly with recurrent otorrhoea, two with postauricular discharge from mastoid abscess, and one with otalgia, postauricular tenderness and neck stiffness. Hearing loss was conductive in 10 patients (76.9 per cent) and sensorineural (severe to profound) in three. No facial nerve palsy was documented. Cholesteatoma was seen in all cases on high resolution computed tomography, and confirmed intra-operatively. Six patients underwent canalplasty with split skin grafting, and seven modified radical mastoidectomy. Six patients recovered well, two needed repeated canalplasty for soft tissue restenosis, and five needed cautery and split skin grafting for mastoid cavity granulation tissue. CONCLUSION: Congenital canal anomaly is uncommon. Canal cholesteatoma should be suspected in all cases, and high resolution temporal bone computed tomography undertaken in all patients aged four years or more. In patients with otorrhoea, the risk of cholesteatoma is greater. Treatment is generally surgery; the type depends on the disease extent.

Stem cell genes are poorly expressed in chondrocytes from microtic cartilage.

OBJECTIVES: This study was aimed to see the difference between chondrocytes from normal cartilage compared to chondrocytes from microtic cartilage. Specific attentions were to characterize the growth of chondrocytes in terms of cell morphology, growth profile and RT-PCR analysis. STUDY DESIGN: Laboratory experiment using auricular chondrocytes. METHODS: Chondrocytes were isolated from normal and microtic human auricular cartilage after ear reconstructive surgeries carried out at the Universiti Kebangsaan Malaysia Medical Centre. Chondrocytes were cultured in vitro and subcultured until passage 4. Upon confluency, cultured chondrocytes at each passage (P1, P2, P3 and P4) were harvested and subjected to growth profile and gene expression analyses. Comparison was made between the microtic and normal chondrocytes. RESULTS: For growth profile analysis cell viability did not show significant differences between both samples. There are no significance differences between both samples in terms of its growth rate, except in passage 1 where microtic chondrocytes were significant lower in their growth rate. Population doubling time and total number of cell doubling of all samples also did not show any significant differences. Gene expression is measured using Real Time-Reverse Transcriptase Polymerase Chain Reaction (RT-PCR). There is no significant differences in the expression of collagen type I, collagen type II, collagen type X, aggrecan core protein, elastin and sox9 genes in both samples. There are significant lower in the expression of sox2, nestin, BST-1 and OCT-4 gene in microtic chondrocytes compared to the normal chondrocytes. Stem cells markers are included in this study as stemness in cells may imply a greater proliferative potential and plasticity in vitro. CONCLUSION: Chondrocytes from microtic samples have the same properties as chondrocytes from normal samples and hold promises to be used as a starting material in the reconstruction of the external ear in future clinical application. The reduction in sox2, nestin, BST-1 and OCT-4 gene expression in microtic samples could be the possible cause of the arrested development of the external ear.

Congenital cholesteatoma: delayed diagnosis and its consequences.

This is a retrospective review of congenital cholesteatoma cases that were managed surgically. There were 5 cases. The age of presentation ranged from 5 to 18 year old. Three patients presented with complication of the disease. Three patients had intact tympanic membrane, two had perforation at the anterior superior quadrant. All patients had cholesteatoma medial to tympanic membrane. Four cases had extensive ossicular erosion with preoperative hearing worse than 40 dB. Four cases underwent canal wall down mastoid surgery and one underwent canal wall up surgery. One patient had recurrence which required revision surgery. In conclusion, congenital cholesteatoma presented late due to the silent nature of disease in its early stage. Extensive disease, ossicular destruction with risk of complication at presentation were marked in our study. Hence, more aggressive surgical intervention is recommended in the management of congenital cholesteatoma.

Otosclerosis and the role of second ear surgery.

Hearing loss and tinnitus are the main symptoms of otosclerosis. Little is known about the cause of tinnitus in otosclerosis and the factors influencing the effect of surgery on tinnitus. Though by surgery, we are able to inform patient about probable hearing gain and even benefit concerning bilateral hearing, it is however difficult to predict the course of tinnitus. The principle aim of stapes surgery is to restore hearing but some patients also report reduction in the severity of tinnitus and even complete cessation of it. We describe a case report of a 37 year old male who underwent a second stapes surgery. We wish to illustrate that for our patient, tinnitus represents a major disturbance and the patient is as much concerned with the improvement of hearing as with the improvement of tinnitus.

Hearing rehabilitation in congenital canal atresia.

INTRODUCTION: The purpose of this study was to review the results of our patients with congenital canal atresia after implantation of bone-anchored hearing aids (BAHA). The occurrence of complications was also reviewed. METHODS: This was a retrospective analysis of the first 16 patients who had BAHA implantation at Universiti Kebangsaan Malaysia Medical Centre, Malaysia. Audiometric assessment was done preoperatively and postoperatively for each patient using the standard procedure. The surgical procedure was described and its complications discussed. RESULTS: The 16 patients consisted of 11 male and five female patients. Their mean age was 8.9 years at the time of the surgery. The main indication was bilateral canal atresia. 11 patients had implantation of BAHA performed in two stages, while the other five patients had it as a single-staged procedure. The complications that occurred were failure of osseointegration (one patient), granulation tissue overgrowth into the abutment (two patients) and cellulitis surrounding the abutment (three patients). The average preoperative unaided air conduction threshold was 64.9 dB and the average postoperative aided hearing threshold was 29.7 dB. The overall mean functional gain was 35.2 dB. CONCLUSION: BAHA has many advantages over the conventional hearing aid in the form of cosmesis, discomfort and hearing gain. It is a reliable hearing rehabilitation tool with good predictable hearing outcome in patients with bilateral canal atresia, especially those unsuitable for canalplasty. Despite its higher cost and the need for surgical implantation, its use is justifiable in properly selected patients.

Metachronous inflammatory myofibroblastic tumour in the temporal bone: case report.

OBJECTIVE: We report an extremely rare case of metachronous inflammatory myofibroblastic tumour in the temporal bone. METHOD: Case report and review of the world literature on metachronous inflammatory myofibroblastic tumour. RESULTS: Inflammatory myofibroblastic tumour in the temporal bone is rare, and metachronous inflammatory myofibroblastic tumour in the temporal bone has never been reported in the English medical literature. We report a case of inflammatory myofibroblastic tumour in the right temporal bone in a 27-year-old woman presenting with right-sided otalgia and progressive hearing loss. A metachronous lesion was discovered in the left temporal bone one year later. The patient underwent surgical excision of the tumour via canal wall down mastoidectomy for both lesions. Long term steroids were prescribed after both surgical procedures. At follow up three years after the last procedure, the patient remained free of disease. CONCLUSION: To the best of our knowledge, this is the first reported case of metachronous inflammatory myofibroblastic tumour in the temporal bone.

Iatrogenic facial nerve palsy: lessons to learn.

INTRODUCTION: This study aims to review the management and discuss the outcome of patients with iatrogenic facial nerve palsy. METHODS: 11 patients with iatrogenic facial nerve palsy (FNP) were evaluated retrospectively in a tertiary centre between June 1995 and September 2008. All the cases were referred from other centres. RESULTS: Ten patients had iatrogenic immediate FNP secondary to mastoidectomy and one had FNP secondary to superficial parotidectomy. Of the ten cases, three had concomitant profound sensorineural hearing loss and one had concomitant labyrinthine fistula. Ten patients underwent facial nerve exploration and one patient was managed conservatively. The second genu was the commonest site of injury (60 percent). Facial nerve recoveries were achieved to Grade I House Brackmann classification in five cases, Grade II in two cases and Grade III in two cases postoperatively. One case defaulted follow-up. One patient, managed conservatively, recovered to FNP Grade II after five months post-injury. CONCLUSION: Mistakes that most likely occurred during mastoid surgery are drilling towards the antrum, causing injury to the facial nerve at the second genu. Early facial nerve exploration and neurolysis resulted in good facial nerve recovery.

Living bilayered human skin equivalent: promising potentials for wound healing.

The angiogenic potential of native skin (NS), keratinocytes single skin equivalent (SSE-K), fibroblasts single skin equivalent (SSE-F) and bilayered skin equivalent secreting angiogenic growth factors such as transforming growth factor beta1 (TGF-beta1), vascular endothelial growth factor (VEGF), keratinocyte growth factor (KGF) and basic fibroblast growth factor (bFGF) in the in vitro systems at 24, 48, 72 hours and 7 days was compared using Enzyme-Linked Immunosorbent Assay (ELISA). Bilayered skin equivalent exhibit highest release of growth factors within 24 hours to 7 days of culture compared to NS, SSE-K and SSE-F. This proved the potential of bilayered skin equivalent in producing and sustaining growth factors release to enhance angiogenesis, fibroblasts proliferation, matrix deposition, migration and growth of keratinocytes.

Benefit and pitfalls of newborn hearing screening.

The importance of universal newborn hearing screening (UNHS) in identifying hearing-impaired infants as early as possible is already well recognized. Transient evoked otoacoustic emissions (TEOAE) have been established as a reliable method for UNHS in full term infants. This is a cross sectional study between April 2003--December 2005. Thirteen thousand five hundred and ninety eight (13,598) newborns were screened for hearing loss with portable otoacoustic emission (OAE) before discharge. The initial coverage rate during the 3 years study period was 85.9% (13,598) with 89.2% (3762), 79.0% (4480) and 90.3% (5356) for 2003, 2004 and 2005 respectively. The mean age when hearing loss was diagnosed using ABR were 3.56 months old, 3.08 months old, and 2.25 months old and 3.01 months old for 2003, 2004, 2005 respectively and it was statistically significant. The defaulter rate at the third stage during the 3 years study period was 35% (21), 15.2% (7) and 18.2% (2) for 2003, 2004 and 2005 respectively. This study showed significant improvement in initial referral rate, coverage rate and age of diagnosis. However, we need to improve on high defaulter rates.

Living bilayered human skin equivalent: promising potentials for wound healing

The angiogenic potential of native skin (NS), keratinocytes single skin equivalent (SSE-K), fibroblasts single skin equivalent (SSE-F) and bilayered skin equivalent secreting angiogenic growth factors such as transforming growth factor beta1 (TGF-beta1), vascular endothelial growth factor (VEGF), keratinocyte growth factor (KGF) and basic fibroblast growth factor (bFGF) in the in vitro systems at 24, 48, 72 hours and 7 days was compared using Enzyme-Linked Immunosorbent Assay (ELISA). Bilayered skin equivalent exhibit highest release of growth factors within 24 hours to 7 days of culture compared to NS, SSE-K and SSE-F. This proved the potential of bilayered skin equivalent in producing and sustaining growth factors release to enhance angiogenesis, fibroblasts proliferation, matrix deposition, migration and growth of keratinocytes.

Reconstruction of living bilayer human skin equivalent utilizing human fibrin as a scaffold.

Our aim of this study was to develop a new methodology for constructing a bilayer human skin equivalent to create a more clinical compliance skin graft composite for the treatment of various skin defects. We utilized human plasma derived fibrin as the scaffold for the development of a living bilayer human skin equivalent: fibrin-fibroblast and fibrin-keratinocyte (B-FF/FK SE). Skin cells from six consented patients were culture-expanded to passage 1. For B-FF/FK SE formation, human fibroblasts were embedded in human fibrin matrix and subsequently another layer of human keratinocytes in human fibrin matrix was stacked on top. The B-FF/FK SE was then transplanted to athymic mice model for 4 weeks to evaluate its regeneration and clinical performance. The in vivo B-FF/FK SE has similar properties as native human skin by histological analysis and expression of basal Keratin 14 gene in the epidermal layer and Collagen type I gene in the dermal layer. Electron microscopy analysis of in vivo B-FF/FK SE showed well-formed and continuous epidermal-dermal junction. We have successfully developed a technique to engineer living bilayer human skin equivalent using human fibrin matrix. The utilization of culture-expanded human skin cells and fibrin matrix from human blood will allow a fully autologous human skin equivalent construction.

Lateral sinus thrombosis.

We describe four cases of lateral sinus thrombosis secondary to otitis media. They presented with low-grade fever, headache, nausea, vomiting and ear discharge. One patient had facial nerve palsy. CT scan was helpful in managing these patients. They were treated with antibiotics followed by surgery. Two patients had intracranial abscesses and were treated accordingly.

Internal auditory canal stenosis in congenital sensorineural hearing loss.

OBJECTIVE: Sensorineural hearing loss (SNHL) due to internal auditory canal (IAC) stenosis with hypoplasia of the cochleovestibular nerve is a rare disorder. The diagnosis of the IAC stenosis requires both high resolution computed tomography scan (HRCT) and magnetic resonance imaging (MRI). METHODS: A retrospective review over 6 years in an academic tertiary referral center was performed. RESULTS: Six patients with congenital SNHL were diagnosed with congenital IAC stenosis. Four had unilateral and two had bilateral IAC stenosis after imaging. MRI showed hypoplastic vestibulocochlear nerve in all cases. CONCLUSIONS: This paper highlights the importance of imaging in diagnosing IAC stenosis and detecting the presence of cochleovestibular nerve in cases of congenital SNHL.

Massive epistaxis secondary to pseudoaneurysm of internal carotid artery.

Post-traumatic pseudoaneurysms of internal carotid arteries are uncommon. The patients may present with massive epistaxis due to rupture of the aneurysm into the sphenoid sinus. Early diagnosis and treatment is mandatory as the likelihood of exsanguinations increases with each subsequent episode of epistaxis. The clinical features of unilateral blindness and massive epistaxis after head injury should indicate the diagnosis. The high mortality of this entity underlines the importance of early angiography in these patients to confirm this diagnosis. We present 3 cases of post-traumatic aneurysm of the ICA.

Rare bone disorder affecting the temporal bone.

Fibrous dysplasia is an uncommon benign disorder of unknown etiology. Rarely, it presents isolated in the temporal bone. We present three cases of monostotic fibrous dysplasia that involved the entire temporal bone.

Newborn hearing screening: experience in a Malaysian hospital.

INTRODUCTION: This study aims to determine the prevalence of hearing loss among newborns delivered at Hospital Universiti Kebangsaan Malaysia and to evaluate the usefulness of our hearing screening protocol. METHODS: All infants born in the hospital over a nine-month period, between April to December 2003, were screened for hearing loss with a portable otoacoustic emission (OAE) before discharge. At the age of two months, a second OAE test was repeated on newborns who failed the initial test. Those who failed the second test were re-tested at three months of age. When these infants failed the third OAE test, a brainstem evoked response (BSER) test was performed. RESULTS: During the study period, 4,219 infants were born in the hospital, and 3,762 (89.2 percent) underwent OAE screening. 620 (19.7 percent) of them failed the first screening test, and 506 (81.6 percent) of them came for a second stage-screening test. In the third stage screening at three months of age, only 39 (65 percent) patients turned up. Of these, ten infants passed the OAE test and 29 failed. However, when these infants underwent BSER, 13 had normal BSER and 16 have abnormal BSER. The prevalence of hearing loss in this study was 0.42 percent (16/3,762). CONCLUSION: The large number of defaulters and false-positive results in this study suggest that this pilot hearing-screen programme requires fine-tuning to minimise these problems.

Congenital deafness: high prevalence of a V37I mutation in the GJB2 gene among deaf school children in Alor Setar.

Twenty percent of all childhood deafness is due to mutations in the GJB2 gene (Connexin 26). The aim of our study was to determine the prevalence and spectrum of GJB2 mutations in childhood deafness in Malaysia. We analyzed the GJB2 gene in 51 deaf students from Sekolah Pendidikan Khas Alor Setar, Kedah. Bidirectional sequencing indicates that 25% of our childhood deafness has mutation in their GJB2 gene. Sixty two percent of these children demonstrate V37I missense mutation. Interestingly, V37I mutation in the GJB2 gene have been reported as polymorphism in Western countries, however in our country it behaved as a potentially disease-causing missense mutation, causing childhood deafness as it was not found in the normal control.