828 kHz retinal imaging with an 840 nm Fourier domain mode locked laser

This paper presents a Fourier domain mode locked (FDML) laser centered around 840 nm. It features a bidirectional sweep repetition rate of 828 kHz and a spectral bandwidth of 40 nm. An axial resolution of ∼9.9 µm in water and a 1.4 cm sensitivity roll-off are achieved. Utilizing a complex master-slave (CMS) recalibration method and due to a sufficiently high sensitivity of 84.6 dB, retinal layers of the human eye in-vivo can be resolved during optical coherence tomography (OCT) examination. The developed FDML laser enables acquisition rates of 3D-volumes with a size of 200 × 100 × 256 voxels in under 100 milliseconds. Detailed information on the FDML implementation, its challenging design tasks, and OCT images obtained with the laser are presented in this paper.

Postoperative radiotherapy delay in head and neck cancer patients undergoing major resection and free flap reconstruction

BACKGROUND

Delays to postoperative radiotherapy (PORT) are frequent and associated with poorer oncologic outcomes in head and neck cancer (HNC) patients. Free flap patients have been suggested as the most at-risk group. Thus, PORT delivery experienced by HNC patients who required a free flap reconstruction was analysed, identifying reasons for the delays if any.

METHODS

A retrospective analysis of a single tertiary unit's PORT delivery to HNC patients undergoing major resection followed by free flap reconstruction between 2017 and 2020.

RESULTS

Eighty-seven patients were identified. Thirty-two patients received PORT within 6 weeks of their surgery date. Reasons for the delays could be categorised into surgery-derived, system-derived and patient-derived reasons. Five patients (5.74%) received PORT >6 weeks after their surgery due to surgical complications. No patients experienced surgical complications during their PORT.

CONCLUSION

In our experience, surgical aspects of free flap reconstructions do not appear to overtly delay or interrupt PORT.

Knowledge, attitudes, and perceptions related to telemedicine among young doctors and nursing staff at the King Abdul-Aziz University Hospital Jeddah, KSA

Objective

To investigate the knowledge, perceptions, and attitude of young doctors and nurses at Kind Abdulaziz University Hospital (KAUH) Jeddah, KSA, regarding the effectiveness of telemedicine in dealing with the patients for either follow-up or continuous monitoring of chronic diseases.

Material and Methods

This prospective cross-sectional study was carried out on the young doctors and nursing staff at KAUH. An online questionnaire addressing all the required fields, i.e., background essential demography, perceptions, acceptance, and knowledge regarding telemedicine's utility, was sent to the targeted population of health care workers. Completed responses were analyzed statistically as per study objectives.

Results

The response rate in our study was 85%. A total of 335 participants responded to our questionnaire. One hundred seventy-one (51.1%) were doctors, whereas one hundred sixty-four (48.9%) were the nursing staff. Among doctors, 50 (29.4%) were recent graduates, whereas, in the nursing side, 77 (46.7%) were the senior nursing students. The knowledge and attitude of the young nursing staff were relatively better than the senior staff taking part in the study and the trends were found statistically significant.

Conclusion

Our study participants, being young, were enthusiastic, had good knowledge regarding the advantages and limitations of telemedicine in managing the selected groups of patients. Their perception and attitude were quite positive. This is an encouraging trend in the promotion of telemedicine as an established way of managing patients with special requirements in an effective way. The ongoing COVID-19 pandemic has highlighted the importance of telemedicine in emergencies to protect both patients and health care workers by reducing chronic patients' avoidable hospital visits.

Determination of a safe INR for joint injections in patients taking warfarin

INTRODUCTION

With an increase in life expectancy in 'developed' countries, the number of elderly patients receiving joint injections for arthritis is increasing. There are legitimate concerns about an increased risk of thromboembolism if anticoagulation is stopped or reversed for such an injection. Despite being a common dilemma, the literature on this issue is scarce.

METHODS

We undertook 2,084 joint injections of the knee and shoulder in 1,714 patients between August 2008 and December 2013. Within this cohort, we noted 41 patients who were taking warfarin and followed them immediately after joint injection in the clinic or radiology department, looking carefully for complications. Then, we sought clinical follow-up, correspondence, and imaging evidence for 4 weeks, looking for complications from these joint injections. We recorded International Normalised Ratio (INR) values before injection.

RESULTS

No complications were associated with the procedure after any joint injection. The radiologists who undertook ultrasound-guided injections to shoulders re-scanned the joints looking for haemarthroses: they found none. A similar outcome was noted clinically after injections in the outpatient setting.

CONCLUSION

With a mean INR of 2.77 (range, 1.7-5.5) and a maximum INR within this group of 5.5, joint injections to the shoulder and knee can be undertaken safely in primary or secondary care settings despite the patient taking warfarin.

Deferral patterns of voluntary blood donors at the National Blood Transfusion Service, North East Zonal Centre, Maiduguri

Appropriate donor selection in an important step in ensuring safe supply of blood and blood products. In this study deferral patterns of voluntary non-renumerated blood donors were determined at the North-Eastern Zonal Centre of the National Blood Transfusion service. The study was conducted between April 2007 and April 2009, and it involved the administration of a structured questionnaire. A total of 4032 voluntary blood donors were recruited, seven hundred and thirteen (17.7%) were temporarily deferred. The commonest reasons for deferral were low haemoglobin, self-deferral, high blood pressure, low weight and high risk behaviour. Other reasons are use of certain medications, low blood pressure and failed venopuncture. Gender analysis showed that more females were deferred for low haemoglobin and more males were self-deferred. Following donor recall, 146 of the 173 donors temporarily deferred came back to donate. These consisted of 113 deferral due to low haemoglobin, 30 self-deferred and 3 induced in risky behaviour. Effective education or counseling, the old tradition of giving haematinics and good dietary advice to those with low haemaglobin values, improved the safety and availability of blood and blood products. Donors who are self-deferred and those involved in high risk bahviour should never be persuaded to donate blood. There is also the need for a review of operational guidelines with regards the uniform acceptable cutoff point of 12.5g/dl haemoglobin value for males and females.

22q11 Deletion in children with cleft lip and palate--is routine screening justified?

OBJECTIVE

To ascertain the prevalence of 22q11 deletion in children with a diagnosis of cleft lip and/or palate that had been referred to the Cleft Lip & Palate Service, Newcastle-upon-Tyne.

DESIGN

Retrospective analysis of results of 22q11 FISH testing performed in all such referrals.

PARTICIPANTS

191 children, of whom 13 had a bilateral cleft lip and palate, two had a median cleft, 77 had a cleft palate only, 44 had a unilateral cleft lip, 47 had a unilateral cleft lip and palate and eight had a submucous cleft palate.

RESULTS

nine patients had a positive 22q11 FISH test.

CONCLUSION

This represents a higher percentage than has been previously reported. All children with cleft lip and/or palate should routinely have a 22q11 FISH test in view of the implications of a diagnosis of velocardiofacial syndrome.

Increased dietary oxalate does not increase urinary calcium oxalate saturation in hypercalciuric rats

BACKGROUND

Human calcium oxalate (CaOx) nephrolithiasis may occur if urine is supersaturated with respect to the solid-phase CaOx. In these patients, dietary oxalate is often restricted to reduce its absorption and subsequent excretion in an effort to lower supersaturation and to decrease stone formation. However, dietary oxalate also binds intestinal calcium which lowers calcium absorption and excretion. The effect of increasing dietary oxalate on urinary CaOx supersaturation is difficult to predict.

METHODS

To determine the effect of dietary oxalate intake on urinary supersaturation with respect to CaOx and brushite (CaHPO4), we fed 36th and 37th generation genetic hypercalciuric rats a normal Ca diet (1.2% Ca) alone or with sodium oxalate added at 0.5%, 1.0%, or 2.0% for a total of 18 weeks. We measured urinary ion excretion and calculated supersaturation with respect to the CaOx and CaHPO4 solid phases and determined the type of stones formed.

RESULTS

Increasing dietary oxalate from 0% to 2.0% significantly increased urinary oxalate and decreased urinary calcium excretion, the latter presumably due to increased dietary oxalate-binding intestinal calcium. Increasing dietary oxalate from 0% to 2.0% decreased CaOx supersaturation due to the decrease in urinary calcium offsetting the increase in urinary oxalate and the decreased CaHPO4 supersaturation. Each rat in each group formed stones. Scanning electron microscopy revealed discrete stones and not nephrocalcinosis. X-ray and electron diffraction and x-ray microanalysis revealed that the stones were composed of calcium and phosphate; there were no CaOx stones.

CONCLUSION

Thus, increasing dietary oxalate led to a decrease in CaOx and CaHPO4 supersaturation and did not alter the universal stone formation found in these rats, nor the type of stones formed. These results suggest the necessity for human studies aimed at determining the role, if any, of limiting oxalate intake to prevent recurrence of CaOx nephrolithiasis.