Ergonomic problems of surgical lighting systems have been indicated by surgeons. However, the underlying causes are not clear. The aim of this study is to assess the problems in detail. Luminaire use during 46 h of surgery was observed and quantified. Furthermore, a questionnaire on perceived illumination of and usability problems with surgical luminaires was issued among OR-staff in 13 hospitals. The results showed that every 7.5 min a luminaire action (LA) takes place, intended to reposition the luminaire. Of these LAs, 74% was performed by surgeons and residents. For 64% of these LAs the surgical tasks of OR-staff were interrupted. The amount of LAs to obtain a well-lit wound, illumination level, shadows, and illumination of deep wounds were most frequently indicated lighting aspects needing improvement. Different kinematic aspects of the pendant system of the lights that influence usability were also mentioned: high forces for repositioning, ease of focusing and aiming, ease of moving, collisions of the luminaire, entangling of pendant arms, and maneuverability. Based on these results, conclusions regarding to improvement of surgical lighting systems are formulated. Focus for improvements should be on minimizing the need for repositioning the luminaire, and on minimizing the effort for repositioning.

Ergonomic problems of surgical lighting systems have been indicated by surgeons; however, the underlying causes are not clear. The aim of this study is to assess the problems in detail. Luminaire use during 46 hours of surgery was observed and quantified. Furthermore, a questionnaire on perceived illumination of and usability problems with surgical luminaires was issued among OR-staff in 13 hospitals. The results showed that every 7.5 minutes a luminaire action (LA) takes place, intended to reposition the luminaire. Of these LAs, 74% were performed by surgeons and residents. For 64% of these LAs the surgical tasks of the OR-staff were interrupted. The amount of LAs to obtain a well-lit wound, the illumination level, shadows, and the illumination of deep wounds were most frequently indicated lighting aspects needing improvement. Different kinematic aspects of the pendant system of the lights that influence usability were also mentioned: High forces for repositioning, ease of focusing and aiming, ease of moving, collisions of the luminaire, entangling of pendant arms, and maneuverability. Based on these results conclusions regarding the improvement of surgical lighting systems are formulated. Focus for improvements should be on minimizing the need for repositioning the luminaire, and on minimizing the effort for repositioning.

Objective illuminance measurements show a wide variation between lights and a superiority of main over auxiliary lights. Uneven light distributions and colored shadows indicate that LED lights still need to converge to an optimal design.

During eye surgery translocating a graft of retinal tissue without damaging the vulnerable top layer is highly problematic using the currently available instruments. This study presents indirect Heat Induced Attachment and Detachment (HIAD) as a new concept for single side attachment of tissue to, and detachment from a heated metal wire. A small-scale prototype was built, having a 50 mum molybdenum wire that could be heated via an electric current. Tests (n = 60) were performed on submerged chicken meat to study the attachment and detachment properties of the prototype at different electric signal lengths. A 9V signal was applied to the prototype, with amplifier input signal lengths varying from 0.6-1.5 ms. Voltages and currents were sampled at 250 kHz to obtain energies. Both attachment and detachment occurred with 98% and 90% certainty, respectively, supplying 41 and 110 mJ of energy to the prototype in 0.7 and 1.5 ms. The attachment strength was estimated at 0.2 mN. Visible damage appeared to be approximately 0.005 mm(2). The concept of indirect heating of the instrument-tissue interface proved to be effective as the prototype could induce attachment and detachment of tissue. Indirect HIAD may be applicable in many different surgical applications.

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