Search

Purpose: To investigate different factors which may play a role in the safety of eye surgery. Method: A survey questionnaire with 22 questions was sent to the members of the UK & Eire Glaucoma Society (UKEGS ) and Midlands Ophthalmic Society (MOS). Results: 73 responses were received within 2 weeks of the survey being sent. 77.78% were consultant ophthalmologists. 96% agreed with seniority being linked to safety of surgery and 89% felt higher volume of surgery performed may reduce complications. Although 89% were right-handed, 7% left-handed and 4% ambidextrous; all the consultants felt that ambidextrous surgeons are the safest. One clinician was colour-blind, but the majority felt that there was no significant evidence linking colour-blindness with poor surgical outcomes. Although almost everyone felt the importance of visual and stereo acuity for eye surgeons, the majority did not have a formal assessment for these for doing their job. 79% respondents felt the need for checking various visual parameters at varying intervals. Hunger, anger, stress & limited time, tiredness and alcohol were deemed to be the greatest risks to safe surgery. Conclusion: Visual parameters are regarded as important for the safety of eye surgeries. However, there is no requirement for formal assessment for these in the NHS; although most surgeons would be happy for these assessments at varying intervals.

This work presents the design and implementation of a firmware prototype that allows multiple Internet Of Things (IoT) protocols to coexist such that they share a single radio. 6LoWPAN over Time Slotted Channel Hopping (TSCH) and Bluetooth Low Energy (BLE) are the two network protocols that are explored in this work. 6LoWPAN over TSCH forms a mesh network of low power embedded devices so that they are globally accessible through their IPv6 addresses. BLE is suitable for the direct connectivity between devices in short radio ranges. Sharing a single radio between diverse protocols is challenging since protocols access the radio in different modes and with different time patterns. The proposed architecture uses radio abstraction layer for dynamically sharing the radio based on the priority of the requests. Furthermore, concurrent operation of protocols is achieved with the help of priority based multitasking of Micrium operating system. Finally, the time critical operations of the TSCH and the radio abstraction module are handled with nested interrupts. The implementation of the firmware is evaluated with mainly two types of experiments. Overall, it is observed from the experiments that both protocols can coexist concurrently and can maintain their connections. In one set of experiments, periodic data is sent over both protocols every 5 seconds (with small random jitter). Basically these experiments involve small data traffic on both protocols. It is observed that the protocol with lower radio priority degrades in performance. Approximately 10% of the packets need re-transmissions, and thus have more latency for the protocol with lower radio priority. The second set of experiments involve file transfers over 3 hops using 6LoWPAN, while one of the middle nodes (acting as a router for the file transfer) also carries BLE session comprising of 17 BLE activities. It is observed that the mean file transfer time with BLE session is delayed compared to the no BLE case. The delay is less than the duration of the two active TSCH slots. This architecture is suitable for sharing a single radio where the network traffic is sparse. This architecture allows small embedded devices with a single radio to be accessible across many protocols without any modifications to the protocol standards. Although the performance degrades in the simultaneous operations, the protocols still keep their respective connections and complete their operations.