Mutation analysis in the long isoform of USH2A in American patients with Usher Syndrome type II.

Usher syndrome type II (USH2) is an autosomal recessive disorder characterized by moderate to severe hearing impairment and progressive visual loss due to retinitis pigmentosa (RP). To identify novel mutations and determine the frequency of USH2A mutations as a cause of USH2, we have carried out mutation screening of all 72 coding exons and exon-intron splice sites of the USH2A gene. A total of 20 USH2 American probands of European descent were analyzed using single strand conformational polymorphism (SSCP) and direct sequencing methods. Ten different USH2A mutations were identified in 55% of the probands, five of which were novel mutations. The detected mutations include three missense, three frameshifts and four nonsense mutations, with c.2299delG/p.E767fs mutation, accounting for 38.9% of the pathological alleles. Two cases were homozygotes, two cases were compound heterozygotes and one case had complex allele with three variants. In seven probands, only one USH2A mutation was detected and no pathological mutation was found in the remaining eight individuals. Altogether, our data support the fact that c.2299delG/p.E767fs is indeed the most common USH2A mutation found in USH2 patients of European Caucasian background. Thus, if screening for mutations in USH2A is considered, it is reasonable to screen for the c.2299delG mutation first.

Cochlear implantation in organ transplantation.

OBJECTIVES/HYPOTHESIS: Compared to immunocompetent patients, organ transplant recipients receiving immunosuppressant medications may experience higher rates of postoperative complications. This study was designed to retrospectively review the outcomes of cochlear implantation among organ transplant patients. STUDY DESIGN: Retrospective case series. METHODS: Five organ transplant patients received seven cochlear implantations at the University of Miami Ear Institute from January 1, 1992, until August 31, 2005. Inpatient and outpatient records were analyzed to identify healing problems, wound infections, and speech recognition after implantation. RESULTS: There were no healing problems, wound infections, or other complications noted among cochlear implant recipients who had also received organ transplantation. Open-set sentence discrimination as measured by the Hearing in Noise Test (HINT), City University of New York (CUNY) test, and/or Central Institute for the Deaf (CID) tests ranged from 46% to 89%. Open-set word recognition as measured by the Consonant Nucleus Consonant (CNC) or the Northwestern University number 6 (NU-6) test ranged from 26% to 64%. CONCLUSIONS: This series suggests that cochlear implantation can be safe and effective for solid organ transplant recipients on immunosuppressants, with discrimination performance within the expected ranges for cochlear implant patients

Safety of modified radical neck dissection for differentiated thyroid carcinoma.

OBJECTIVES/HYPOTHESIS: The management of cervical metastases from differentiated thyroid carcinoma (DTC) remains controversial. Most surgeons perform a neck dissection (ND) for clinically apparent disease. The extent of nodal dissection varies from regional to comprehensive. Morbidity from ND in the setting of DTC remains high, particularly when performed in the setting of a thyroidectomy (TT). To determine complications from ND for DTC, we retrospectively reviewed our surgical experience of modified radical neck dissection for nodal metastases. STUDY DESIGN: Retrospective chart review. METHODS: Between 1997 and 2002, 39 consecutive patients (31 females and 8 males) underwent 44 comprehensive NDs of levels II-V for DTC. Central compartment dissection (CCD) (levels VI and VII) was also performed during 23 of these procedures. Twenty (45.5%) patients had prior treatment elsewhere. Preoperative pathology revealed papillary carcinoma in 22 patients (56.4%), tall cell variant in 11 (28.2%), and follicular variant in 6 (15.4%). RESULTS: Ten patients (20%) underwent ND alone, whereas 6 (14%) underwent simultaneous ND and TT. Fifteen patients underwent simultaneous ND, TT, and CCD (30%). Temporary hypocalcemia occurred after 21% of NDs that were performed in the setting of either TT or CCD or both. There were no cases of permanent hypoparathyroidism. Transient regional lymph node (RLN) paresis occurred in two patients and was associated with a concomitant central compartment nodal dissection; there were no permanent RLN palsies. Transient spinal accessory nerve paresis developed after 27% of NDs performed. Two patients developed chyle leaks. CONCLUSIONS: When ND is necessary for the treatment of thyroid malignancies, the procedure can be performed safely with acceptable morbidity.