Passive Transcutaneous Bone Conduction Hearing Implants: A Systematic Review.

OBJECTIVE: To systematically review the literature on currently available passive transcutaneous bone conduction hearing implants (pTCBI) with regard to complications, audiological outcomes, and quality-of-life scores. DATA SOURCES: MEDLINE, EMBASE, Scopus, and Cochrane Library. STUDY SELECTION: All identified English-language articles reporting on the implantation of currently available pTCBI's and their complications. Both pediatric and adult patients were included. No limitation was placed on study design or level of evidence. DATA EXTRACTION: Complications, audiological outcomes including mean pure-tone average gain and mean speech reception threshold gain, and quality-of-life outcomes. DATA SYNTHESIS: Twenty-six articles were included in the review. Four hundred eighty-two pTCBIs have been reported in the literature. Major complications including skin breakdown, wound dehiscence, hematoma, seroma, and inability to use the device occurred in 5.2% of patients. Minor complications including pain and self-resolving erythema at the implant site occurred in 13.1% of the patients. The weighted mean pure-tone average gain of the two included devices was 28.4 ±â€Š2.1 dB and the mean speech reception threshold gain was 32.9 ±â€Š3.9 dB. Favorable quality-of-life scores have been demonstrated with pTCBIs. CONCLUSION: pTCBIs are a viable alternative to percutaneous devices in a carefully selected group of patients. These devices have demonstrated good audiological outcomes, low morbidity, and high patient satisfaction.

The Role of Ultrasound Compared to Biopsy of Temporal Arteries in the Diagnosis and Treatment of Giant Cell Arteritis (TABUL): a diagnostic accuracy and cost-effectiveness study.

BACKGROUND: Giant cell arteritis (GCA) is a relatively common form of primary systemic vasculitis, which, if left untreated, can lead to permanent sight loss. We compared ultrasound as an alternative diagnostic test with temporal artery biopsy, which may be negative in 9-61% of true cases. OBJECTIVE: To compare the clinical effectiveness and cost-effectiveness of ultrasound with biopsy in diagnosing patients with suspected GCA. DESIGN: Prospective multicentre cohort study. SETTING: Secondary care. PARTICIPANTS: A total of 381 patients referred with newly suspected GCA. MAIN OUTCOME MEASURES: Sensitivity, specificity and cost-effectiveness of ultrasound compared with biopsy or ultrasound combined with biopsy for diagnosing GCA and interobserver reliability in interpreting scan or biopsy findings. RESULTS: We developed and implemented an ultrasound training programme for diagnosing suspected GCA. We recruited 430 patients with suspected GCA. We analysed 381 patients who underwent both ultrasound and biopsy within 10 days of starting treatment for suspected GCA and who attended a follow-up assessment (median age 71.1 years; 72% female). The sensitivity of biopsy was 39% [95% confidence interval (CI) 33% to 46%], which was significantly lower than previously reported and inferior to ultrasound (54%, 95% CI 48% to 60%); the specificity of biopsy (100%, 95% CI 97% to 100%) was superior to ultrasound (81%, 95% CI 73% to 88%). If we scanned all suspected patients and performed biopsies only on negative cases, sensitivity increased to 65% and specificity was maintained at 81%, reducing the need for biopsies by 43%. Strategies combining clinical judgement (clinician's assessment at 2 weeks) with the tests showed sensitivity and specificity of 91% and 81%, respectively, for biopsy and 93% and 77%, respectively, for ultrasound; cost-effectiveness (incremental net monetary benefit) was £485 per patient in favour of ultrasound with both cost savings and a small health gain. Inter-rater analysis revealed moderate agreement among sonographers (intraclass correlation coefficient 0.61, 95% CI 0.48 to 0.75), similar to pathologists (0.62, 95% CI 0.49 to 0.76). LIMITATIONS: There is no independent gold standard diagnosis for GCA. The reference diagnosis used to determine accuracy was based on classification criteria for GCA that include clinical features at presentation and biopsy results. CONCLUSION: We have demonstrated the feasibility of providing training in ultrasound for the diagnosis of GCA. Our results indicate better sensitivity but poorer specificity of ultrasound compared with biopsy and suggest some scope for reducing the role of biopsy. The moderate interobserver agreement for both ultrasound and biopsy indicates scope for improving assessment and reporting of test results and challenges the assumption that a positive biopsy always represents GCA. FUTURE WORK: Further research should address the issue of an independent reference diagnosis, standards for interpreting and reporting test results and the evaluation of ultrasound training, and should also explore the acceptability of these new diagnostic strategies in GCA. FUNDING: The National Institute for Health Research Health Technology Assessment programme.

Calcification of hydrophilic acrylic intraocular lenses in combined phacovitrectomy surgery.

UNLABELLED: Two cases of postoperative intraocular lens (IOL) calcification in patients implanted with the Akreos Adapt IOL at the time of combined phacovitrectomy are described, along with clinical review of all patients implanted with this IOL type at our institution between November 2006 and September 2008. The IOLs explanted from the 2 cases were examined using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The SEM of the explanted IOLs showed crystalline anterior surface and subsurface deposits; by EDX, the deposits showed high concentrations of calcium and phosphorous, consistent with calcium apatite. Twenty patients (20 eyes) attended for cohort review, and none showed IOL opacification. The reason calcification occurred in the 2 cases remains unknown, but clinicians should be aware of this potential complication. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Ultrastructural evaluation of explanted opacified Hydroview (H60M) intraocular lenses.

AIM: To describe the ultrastructural appearance of explanted opacified Hydroview H60M intraocular lenses. METHODS: 14 explanted lenses were examined by scanning electron microscopy, and their appearance compared with a non-implanted H60M lens from the same time period. Wavelength-dispersive x ray spectroscopy (WDX) was performed on two opacified lenses. RESULTS: Subsurface deposits were seen in all explanted opacified lenses. These deposits broke only onto the surface of more densely opacified lenses. WDX confirmed that the deposits contained both calcium and phosphorous, consistent with their being calcium apatite. CONCLUSION: These findings challenge the widely accepted opinion that H60M intraocular lens opacification begins on the surface of the optic.

Estimated neuronal populations and volumes of the hippocampus and its subfields in schizophrenia.

OBJECTIVE: It has been suggested that the primary focus of the pathological process in schizophrenia is on the limbic system, and there have been several postmortem reports of changes in the histological structure or volume of the hippocampus, as well as a larger number of MRI reports of volume reductions. There are conflicting findings, however, with both techniques. METHOD: The authors conducted a study of the gross and subfield structure and cellular composition of the hippocampus in postmortem brains from 30 patients with DSM-IV-diagnosed schizophrenia (13 women, 17 men) and 29 comparison subjects with no psychopathology (14 women, 15 men). Stereological sampling procedures were applied to 25-microm-thick coronal paraffin sections taken at 5-mm intervals throughout the formalin-fixed hippocampus. Subfields were defined as the dentate fascia, the hilus (CA4), an amalgamation of the CA2 and CA3 subfields, the CA1 subfield, and the subiculum. Volumes, cell densities, and cell numbers of the subfields were assessed microscopically, and the volume of the hippocampus was estimated from both photographs and histological slides of the coronal slices. RESULTS: As assessed from histologically stained slides, the volumes of the hippocampus and its subfields did not differ between patients and comparison subjects. Left-sided reduction in hippocampal volumes estimated from photographs, which may have included parahippocampal tissue, was not confirmed on histological examination. No significant differences were observed between patients and comparison subjects in the cellular composition of the hippocampus. CONCLUSIONS: These findings do not support a primary alteration of the hippocampus in schizophrenia.