How I approach trabeculectomy surgery

The purpose of this article is to describe an approach to the most commonly performed surgical treatment for open-angle glaucoma, trabeculectomy. It is important to recognise that the concept of trabeculectomy surgery can be difficult for patients to comprehend in the first place. Their disease is frequently ‘thrust upon them’ by doctors; in other words, they are frequently asymptomatic in the eye that the ophthalmologist is most concerned about. The therapy, at best, can only hope to maintain vision. Vision may well deteriorate as a result of the therapy. These concepts are vital in the consideration of any surgical intervention. Preventive therapy is always more difficult to introduce. This also means the surgeon is all the more challenged to produce the safest possible result. A well-rested surgeon and a calm surgical environment is the start, along with a confident surgical technique. The purpose of trabeculectomy surgery is to create a guarded fistula through which aqueous can drain from the anterior chamber, leading to a steady-state reduced intraocular pressure. If this intervention is appropriate for a patient, drainage surgery has been demonstrated to give long-term intraocular pressure control and visual field preservation. The main complication of this procedure is a failure of drainage due to a scarring response. Other complications include hypotony (low pressure in the eye), infection, and haemorrhage. This article describes each step and lists points for you as a surgeon to consider. It is based on the assumption that the decision to operate is appropriate. What matters is your results. Follow-up of your surgery is vital so you know how successful your surgery is and can take steps to remedy the deficiencies you identify

Pax7 lineage contributions to the mammalian neural crest.

BackgroundNeural crest cells are vertebrate-specific multipotent cells that contribute to a variety of tissues including the peripheral nervous system, melanocytes, and craniofacial bones and cartilage. Abnormal development of the neural crest is associated with several human maladies including cleft/lip palate, aggressive cancers such as melanoma and neuroblastoma, and rare syndromes, like Waardenburg syndrome, a complex disorder involving hearing loss and pigment defects. We previously identified the transcription factor Pax7 as an early marker, and required component for neural crest development in chick embryos. In mammals, Pax7 is also thought to play a role in neural crest development, yet the precise contribution of Pax7 progenitors to the neural crest lineage has not been determined.Methodology/principal findingsHere we use Cre/loxP technology in double transgenic mice to fate map the Pax7 lineage in neural crest derivates. We find that Pax7 descendants contribute to multiple tissues including the cranial, cardiac and trunk neural crest, which in the cranial cartilage form a distinct regional pattern. The Pax7 lineage, like the Pax3 lineage, is additionally detected in some non-neural crest tissues, including a subset of the epithelial cells in specific organs.Conclusions/significanceThese results demonstrate a previously unappreciated widespread distribution of Pax7 descendants within and beyond the neural crest. They shed light regarding the regionally distinct phenotypes observed in Pax3 and Pax7 mutants, and provide a unique perspective into the potential roles of Pax7 during disease and development

Glaucomas in Africans

It is with great pleasure I accept the task to produce a series of thought windows on a subject that challenges me daily ... the glaucomas! I thought a series of short pieces might be more digestible, so if, for example, you feel frustrated that I have not amplified on disc diagnosis for the glaucomas or classification of the glaucomas, etc., then either drop me a note with suggestions or wait a little and the subject may crop up anyway in fullness of time

Murdoch and the End of Ideology

Iris Murdoch had a lifelong interest in politics and she reflected upon the nature of ideology throughout her career. What she had to say on the subject developed during her career and relates to general academic discussions on the nature of ideology. At the outset of her career she was a committed socialist. She recognised that political ideology was in retreat after the Second World War but sought to contribute to socialist ideology. Later in her career she became sceptical of radical utopian ideologies, including socialism and developed a theory of politics that prioritised safeguarding individual liberty and security. However, she imagined that political thought would continue to develop and offer new possibilities and so she did not call for the end of ideology but continued to value political ideas

Corneal Intelligence

No Abstract

Initial experience in self-monitoring of intraocular pressure.

Background/aims: Diurnal variation in intraocular pressure (IOP) is a routine assessment in glaucoma management. Providing patients the opportunity to perform self-tonometry might empower them and free hospital resource. We previously demonstrated that 74% of patients can use the Icare® HOME tonometer. This study further explores Icare® HOME patient self-monitoring. Methods: Patients were trained by standard protocol to use the Icare® HOME rebound tonometer. Patient self-tonometry was compared to Goldmann applanation tonometry (GAT) over one clinical day. Following this, each patient was instructed to undertake further data collection that evening and over the subsequent two days. Results: Eighteen patients (35 eyes) participated. Good agreement was demonstrated between GAT and Icare® HOME for IOPs up to 15 mm Hg. Above this IOP the Icare® tended to over-read, largely explained by 2 patients with corneal thickness >600 um. The mean peak IOP during ‘clinic hours’ phasing was 16.7 mm Hg and 18.5 mm Hg (p = 0.24) over three days. An average range of 5.0, 7.0 and 9.8 mm Hg was shown during single day clinic, single day home and three day home phasing respectively (p =<0.001). The range of IOP was lower in eyes with prior trabeculectomy (6.1 mm Hg vs 12.2 mm Hg). All patients undertook one reading in the early morning at home with an average of 4.8 readings during, and 3.1 readings after office hours. Conclusions: This small study shows that self-tonometry is feasible. The findings from home phasing demonstrated higher peak and trough IOPs, providing additional clinical information. Home phasing is a viable alternative. The cost-effectiveness of this approach has yet to be addressed

Impact of supply problems of preservative-free glaucoma medications on patients and hospital staff

PURPOSE: Glaucoma is a chronic ocular disease, which is usually managed with long-term daily medical therapy, in the form of eye drops. Patients who are intolerant to preservatives in topical medicines require preservative-free versions. From early 2011 patients attending Moorfields Eye Hospital, London, UK, started to report recurring problems with the supply of the following preservative-free glaucoma medications: Timolol 0.25% (Timoptol 0.25%, MSD UK); Dorzolamide (Trusopt, MSD UK); Dorzolamide and Timolol 0.5% (Cosopt, MSD UK). This study investigates the impact of the supply problems of these medications at Moorfields Eye Hospital from a patient, administrative and clinical perspective. METHODS: Information was sought by interviewing both patients and hospital staff, and by a retrospective case note review between April 2010 and May 2013. RESULTS: Many hospital roles, both administrative and clinical, were involved in attempting to resolve the impact of the supply problems. All staff reported a considerable increase in their workload. At the peak of the problem, the glaucoma secretaries received about 150 enquiries per week. A review of 83 sets of patient notes, retrieved from a random sample of 125 patients, showed that 22% encountered a supply problem. Of these, more than one-third attended Moorfields Eye Hospital Accident & Emergency (A&E) for repeat supplies and 89% eventually had their medication changed. In telephone interviews with 39 of a random sample of 50 patients (a subset of the 83 notes retrieved), 59% of the interviewees reported a supply problem. Of these, one-third attended Moorfields Eye Hospital A&E for repeat supplies and half eventually required an alternative medication. Some patients reported going to considerable lengths to obtain ongoing supplies in the community. CONCLUSIONS: This study shows that medication supply problems can have a major impact on patients and hospital services. Supply problems occur across many fields of medicine and with increasing frequency. The findings of this study highlight the importance of early communication of impending shortages between manufacturers and the Department of Health, as recommended in the best practice guidelines. In order to minimise the impact of medicine shortages on patients, clinicians and administrative staff, hospitals need immediate notification of potential supply problems and clear updates on supply resolution. In addition, hospitals should consider nominating an individual as a contact point for patient enquiries regarding medicine supply problems

Evaluation of a new rebound tonometer for self-measurement of intraocular pressure

Background/aims To compare the accuracy of self-obtained, partner-obtained and trainer-obtained measurements using the handheld Icare Home rebound tonometer with Goldmann applanation tonometry (GAT), and to evaluate the acceptability to subjects of Icare Home measurement. Methods 76 subjects were trained to use Icare Home for self-measurement using a standardised protocol. A prespecified checklist was used to assess the ability of a subject to perform self-tonometry. Accuracy of Icare Home self-measurement was compared with GAT using one eye per subject, randomly selected. Bland-Altman difference analysis was used to compare Icare Home and GAT intraocular pressure (IOP) estimates. Acceptability of self-tonometry was evaluated using a questionnaire. Results 56 subjects (74%, 95% CI 64 to 84) were able to correctly perform self-tonometry. Mean bias (95% limits of agreement) was 0.3 mm Hg (−4.6 to 5.2), 1.1 mm Hg (−3.2 to 5.3) and 1.2 mm Hg (−3.9 to 6.3) for self-assessment, partner-assessment and trainer-assessment, respectively, suggesting underestimation of IOP by Icare Home tonometry. Differences between GAT and Icare Home IOP were greater for central corneal thickness below 500 µm and above 600 µm than data points within this range. Acceptability questionnaire responses showed high agreement that the self-pressure device was easy to use (84%), the reading was quick to obtain (88%) and the measurement was comfortable (95%). Conclusions Icare Home tonometry can be used for self-measurement by a majority of trained subjects. IOP measurements obtained using Icare Home tonometry by self-assessment and third party-assessment showed slight underestimation compared with GAT

Educating through Exemplars: Alternative Paths to Virtue

This paper confronts Zagzebski’s exemplarism with the intertwined debates over the conditions of exemplarity and the unity-disunity of the virtues, to show the advantages of a pluralistic exemplar-based approach to moral education (PEBAME). PEBAME is based on a prima facie disunitarist perspective in moral theory, which amounts to admitting both exemplarity in all respects and single-virtue exemplarity. First, we account for the advantages of PEBAME, and we show how two figures in recent Italian history (Giorgio Perlasca and Gino Bartali) satisfy Blum’s definitions of ‘moral hero’ and ‘moral saint’ (1988). Then, we offer a comparative analysis of the effectiveness of heroes and saints with respect to character education, according to four criteria derived from PEBAME: admirability, virtuousness, transparency, and imitability. Finally, we conclude that both unitarist and disunitarist exemplars are fundamental to character education; this is because of the hero's superiority to the saint with respect to imitability, a fundamental feature of the exemplar for character education