Persistant dysphonia following endotracheal intubation

Voice production is a complex process that involves more than one system, yet most causes of dysphonia are attributed to disturbances in the laryngeal structures and little attention is paid to extralaryngeal factors. Persistent dysphonia after general anesthesia is a challenge to both anesthesiologists and otolaryngologists. The etiology is often multivariable and necessitates a team approach for proper diagnosis. Laryngeal symptoms are subdivided into phonatory disturbances and airway related complaints. When they become persistent for more than 72 hours or are coupled with airway symptoms such as hemoptysis, stridor, dyspnea or aspiration, the anesthesiologist should suspect injury to the vocal folds or cricoarytenoid joints. Here-below, the laryngeal manifestations of endotracheal intubation and the pathophysiology of vocal fold scarring are discussed.     

A metabolomic approach to ionotropic glutamate receptor subtype function: a nuclear magnetic resonance in vitro investigation.

A range of behaviours are elucidated via ionotropic glutamate receptors (iGluR). In this work, we examined the acute activation of iGluRs by a range of receptor ligands and effectors to see whether distinguishable metabolic sequelae were elucidated by the activity. We used a guinea-pig brain cortical tissue slice model using targeted receptor ligands ((RS)-(tetrazol-5-yl)glycine (TZG), (5S,10R)-(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate (MK-801, dizocilpine), cis-4-[phosphomethyl]-piperidine-2-carboxylic acid (CGS 19755), (RS)-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid, (2S, 3S, 4S)-2-carboxy-4-(1-methylethenyl)-3-pyrrolidineacetic acid (kainate) and D-serine (D-Ser), as well as compounds (quinolinic acid and kynurenic acid (KynA)) involved in some neuroinflammatory responses. The data were derived using 13C and 1H NMR spectroscopy, and analysed by metabolomic approaches and multivariate statistics. The metabolic effects of agonists at the three major classes of iGluR were easily separated from each other using this method. The classical N-methyl-D-aspartate receptor agonist TZG and the antagonist CGS 19755 produced excitatory and inhibitory metabolic responses, respectively, while the blocker MK-801 resulted in a significant decrease in net metabolism and produced the largest decrease in all metabolite pool sizes seen by any glutamatergic ligand we have studied. Quinolinic acid and KynA produced similar acute metabolic responses, which were unlike those to TZG or CGS 19755, but similar to that of D-Ser. D-Ser was highly stimulatory of net flux into the Krebs cycle. These data show that the metabolic response to iGluR perturbation in vitro is a sensitive discriminator of function.     

Analysis of glutathione <Emphasis Type="Italic">S</Emphasis>-transferase Pi isoform (GSTP1) single-nucleotide polymorphisms and macular telangiectasia type 2

Recent imaging studies have suggested that macular pigment is decreased centrally in macular telangiectasia type 2 (MT2). The uptake of xanthophyll pigment into the macula is thought to be facilitated by a xanthophyll-binding protein (XBP). The Pi isoform of glutathione S-transferase (GSTP1) represents one such XBP with high binding affinity. This case–control study aimed to determine whether two common single-nucleotide polymorphisms (SNPs) of GSTP1 were associated with MT2. DNA samples from 39 cases and 21 controls were collected. Two polymorphic sites of Ile105Val and Ala114Val in exons 5 and 6 respectively, of the GSTP1 gene were analysed. Comparison of alleles and genotypes between cases and controls indicated that there were no statistically significant differences for either the Ile105Val SNP (P = 0.43) or the Ala114Val SNP (P = 0.85), or for any combinations; however, the homozygous at-risk genotype (GG) of the Ile105Val SNP was present in 8% of cases but absent in controls. This study found no statistically significant association between two common GSTP1 SNPs and MT2; however, a trend towards a greater frequency of the GG genotype of the Ile105Val SNP in cases is of great interest. The biological plausibility of disturbed macular pigment uptake in MT2 makes GSTP1 an excellent candidate gene. Further investigation is warranted in future studies of MT2.     

Two-wavelength fundus autofluorescence and macular pigment optical density imaging in diabetic macular oedema

Purpose

To evaluate the application of 488 and 514 nm fundus autofluorescence (FAF) and macular pigment optical density (MPOD) imaging in diabetic macular oedema (DMO) and to demonstrate the typical imaging features.

Patients and Methods

A hundred and twenty-five eyes of 71 consecutive patients with diabetic retinopathy who underwent examination at a specialist university clinic employing a modified Heidelberg Retina Angiograph, using two different light sources of 488 and 514 nm wavelength, were retrospectively reviewed. MPOD images were calculated using modified Heidelberg Eye Explorer software. All images were evaluated by two independent masked graders. Features from FAF and MPOD images were correlated with optical coherence tomography (OCT) imaging findings and inter-grader variability, sensitivity and specificity were calculated using OCT as reference.

Results

Sixty-seven eyes had DMO on OCT. The inter-grader variability was 0.84 for 488 nm FAF, 0.63 for 514 nm FAF and 0.79 for MPOD imaging. Sensitivity and specificity for detection of DMO were 80.6 and 89.7% for 488 nm FAF; 55.2 and 94.8% for 514 nm FAF; and 80.6 and 91.4% for MPOD imaging. In 488 nm FAF and MPOD imaging, DMO was better visualised in comparison with 514 nm FAF imaging, P<0.01. MPOD revealed displacement of macular pigment by intraretinal cysts.

Conclusion

MPOD imaging, and particularly its combination with 488 nm and 514 nm FAF, provides a valuable addition to OCT in the evaluation of DMO and is clinically useful in rapid en-face assessment of the central macula.     

Gentherapie bei Netzhautdystrophien

Genetic mutations are the cause of inherited retinal dystrophies. The underlying genetic basis of these diseases suggests that a gene therapy approach is logical either to replace or reduce the expression of defective genes. The first proof-of-concept clinical studies in patients with Leber's congenital amaurosis have suggested that retinal gene therapy is safe and potentially effective, at least for specific disease entities. In contrast to pharmacological treatment gene therapy has the advantage of being able to express a protein within specific cell populations and is a potentially definitive therapy. Besides replacing deficient genes in inherited diseases, additional strategies that might broaden the application of retinal gene therapy are also being developed. These include the permanent expression of neuroprotective substances or photosensitive molecules (so-called optogenetics). This overview discusses the current clinical strategies and potential problems of retinal gene therapy.     

Free tensor fasciae latae flap for abdominal wall reconstruction: overview and new innovation

Extensive abdominal wall defects may result from tumor extirpation, traumatic injury, or soft tissue infections. Extensive traumatic injuries can often disrupt the soft tissue content of the abdomen as well as the bony support provided by the pelvis. Reconstruction of the lower abdomen should aim to recreate dynamic stability. Five patients with extensive lower abdominal wall disruption following traumatic injuries or infection were treated using a novel flap for functional reconstruction. We devised a free neurotized osteomyocutaneous tensor fasciae latae (TFL) flap that would restore bony continuity by providing a vascularized bone graft and simultaneously maintain the integrity of the attachment of the tensor fascia latae muscle to the iliac crest, reestablishing musculofascial continuity. A branch of the superior gluteal nerve was harvested with this composite flap and coapted to an intercostal nerve for reinnervation, thereby creating a dynamic muscle in these patients. All patients underwent successful free tissue reconstruction with 100% flap survival. The lower abdominal wall and bony integrity of the pelvis were successfully reconstructed. Reinnervation has shown clinical signs of maintained dynamic stability. The innervated TFL osteomyocutaneous flap is an ideal option for lower abdominal reconstruction in patients with complex abdominoperineal defects with loss of bony integrity.