Decompression of the endolymphatic sac for Ménière's disease gives unpredictable results. This may be because the sac is difficult to identify and decompress accurately without causing surgical trauma.

In order to test this idea, transmastoid decompression was simulated in 5 cadaver half heads and the anatomy of the endolymphatic sac was reviewed in a further 14 specimens.

The endolymphatic sac was found and confirmed by histology in all five simulated decompressions. A newly described feature, a trapezoid thickening of dura, was a useful guide. The review showed that the sac was constant proximally, but variable distally. The posterior semicircular canal, posterior fossa dura and sigmoid sinus are at risk during dissection.

The endolymphatic sac may be identified on inspection by an overlying patch of dura, thereby reducing exploratory dissection. It is best to decompress the sac as far proximally as possible, whilst protecting the posterior semicircular canal.

The adoption of evidence-based practice is fundamental to good medical care; it ensures that intervention is clinically effective and safe. In a world of limited healthcare resources, consideration of cost-effectiveness must, unfortunately, restrict clinicians' choice. The National Institute for Health and Clinical Excellence has, for over 10 years, developed guidance to achieve a national consensus on best practice.

This review describes the Institute's methodology, examines guidance relevant to otolaryngology and presents more recent research to update the evidence.

Tranexamic acid is a synthetic antifibrinolytic drug. It has been widely available for over 40 years, but only recently has it started to be used routinely in many surgical disciplines. For ENT surgeons, epistaxis and post-tonsillectomy bleeding contribute a significant proportion of the morbidity and emergency workload in a general ENT department. Published evidence indicates a potentially helpful role for tranexamic acid in managing epistaxis.

To date, the benefits of tranexamic acid as a prophylactic treatment to reduce the rate and severity of post-tonsillectomy bleeding are less certain. Two recently published pilot studies looking at primary haemorrhage in children and secondary haemorrhage in adults following tonsillectomy suggest that further large, randomised trials should explore the efficacy of tranexamic acid in routine ENT surgery. There are potential reductions in patient morbidity and cost savings if tranexamic acid is found to be efficacious in larger trials.

This second segment of the two-part review summarises several modern high-throughput methods in genomics, epigenetics and molecular biology. Many principles from nucleotide sequencing and transcriptomics can be applied to other high-throughput molecular biology techniques. Specifically, this manuscript reviews: array comparative genome hybridisation; single nucleotide polymorphism arrays; microarray technology, used to study epigenetics; and methodology applied in proteomics. Finally, the review describes current methods for the integration of multiple molecular biology platforms.

Progress in treating human disease in general will require close collaboration with experts in bioinformatics. Improved understanding, by clinicians and physician-scientists in our field, of the concepts presented in both parts of this review will advance diagnosis and therapy for diseases of the head and neck.

Advances in high-throughput molecular biology, genomics and epigenetics, coupled with exponential increases in computing power and data storage, have led to a new era in biological research and information. Bioinformatics, the discipline devoted to storing, analysing and interpreting large volumes of biological data, has become a crucial component of modern biomedical research. Research in otolaryngology has evolved along with these advances.

This review highlights several modern high-throughput research methods, and focuses on the bioinformatics principles necessary to carry out such studies. Several examples from recent literature pertinent to otolaryngology are provided. The review is divided into two parts; this first part discusses the bioinformatics approaches applied in nucleotide sequencing and gene expression analysis.

This paper demonstrates how high-throughput nucleotide sequencing and transcriptomics are changing biology and medicine, and describes how these changes are affecting otorhinolaryngology. Sound bioinformatics approaches are required to obtain useful information from the vast new sources of data.