A n Inexpensive Z o o m Double Operating Microscope System M. J. Thompson, Christine M. Evans and R. W. Bl.amey
AN INEXPENSIVE ZOOM DOUBLE OPERATING MICROSCOPE SYSTEM M. J. T H O M P S O N , C H R I S T I N E M. E V A N S and R. W. B L A M E Y , N o t t i n g h a m Microvascular surgery on small animals is useful in research, but commercial operating microscopes are expensive. The cheaper system which is described here has been used successfully in N o t t i n g h a m for microvascular surgery in small animals (renal transplantation in the rat, for example). It could easily be adapted for similar procedures in man, such as the replantation of severed digits. MATERIALS The equipment (Figs. 1 and 2) consists of two Nikon I SMZ-6 stereoscopic zoom microscopes with 30 ~ inclined eyepiece tubes, a Vickers 2 light source, two zoom control units, and a table with two shelves. There are thre e ocular lenses and three auxiliary objectives available, giving a total magnification range of x 5.4 to x 112. Personal requirements determine which combination of these lenses provides the best total magnification range (Table 1). The main objective lens provides a continuously variable magnification within the range x 0.9 to x 4, and this lens combined with the x 10 ocular lens and the AL5 auxiliary objective lens is ideal for procedures such as micro vascular anastomoses (Fig. 3); this is a total magnification range of x 5.4 to x 24.
Fig. 1. General view of equipment. R. W. Blarney, F.R.C.S., General Hospital, Nottingham, NGI 6HA. From the Dept. of Surgery University of Nottingham. The H a n d ~ V o l . 9
No. 1
1977
67
An Inexpensive Zoom Double Operating Microscope System M. 1. Thompson, Christine M. Evans and R. W. BI,amey
[3
C,
I1( i ... h
\ Fig. 2.
Specification of table. TABLE 1 T O T A L M A G N I F I C A T I O N S A N D W O R K I N G DISTANCES O B T A I N A B L E
Working Distance (rarn) Auxiliary objectives Objective
Magnification Eyepieces 10 x 15 x 20 x
77.5
100 AL5 (0.6 x)
85 AL7 (0.8 x)
45 A L 15 (1.4 x)
0.9 - 4.0 x 0.9 - 4.0 x 0.9 - 4.0 x 0.9 - 4.0 x Total Field Total Field Total Field Total Field mag. (mm) mag. (ram) mag. (mm) mag. (ram) 9.0-40.0 x 25.3 5.7 5.4-24.0x 41.7-9.4 7.2-32.0x 31.5-7.1 12.6- 56,0 x 18.0-4.0 13.5-60.0 x 13.3-3.0 8.I-36.0x 22.2-5.0 10.8-48.0x 16.7-3.8 18.9- 84.0 x 9.3-2.1 18.0-80.0 x 12.0-2.7 10.8-48.0x 20.0-4.5 14.4-64.0x 15.1-3.5 25.2-112.0x 8.4-1.9
Small motors are attached to the magnification and focussing controls of each microscope and are operated by foot pedals. Each microscope has one pair of foot pedals for operating the focussing motor, and one pair for operating the zoom ring motor which adjusts the total magnification. A camera can be mounted
on a special attachment
w h i c h fits o n a n e y e p i e c e
tube.
1. Nikon (Projectina, Ayrshire, England). 2. Vickers (York, England). I l l u m i n a t i o n is p r o v i d e d v i a a d u a l s t r a n d f i b r e - o p t i c s y s t e m , f r o m a v a r i a b l e i n t e n s i t y l i g h t - b o x ( V i c k e r s ) w h i c h u s e s a 12 v o l t , 50 w a t t , t u n g s t e n - h a l o g e n l a m p . T h i s g i v e s t w o c i r c u l a r b e a m s of c o l d l i g h t w i t h u n i f o r m l y b r i g h t fields, e a c h o f w h i c h c a n b e m a n o e u v r e d i n t o t h e b e s t p o s i t i o n . T h e w o r k i n g d i s t a n c e is d e p e n 68
The Hand--Vol. 9
No. 1
1977
An Inexpensive Zoom Double Operating Microscope System M. J. Thompson, Christine M. Evans and R. W. Blamey
Fig. 3. Anastomosis of renal vein in thc rat--magnification x 5.4. R ----Renal vein. S = Scoville-Lewis microvascular clamp. The rat renal vein is comparable in size (l-l.5mm) with a human digital artery at the level of the metacarpophalangeal joint. The width of this field is equivalent to 1.5cm. dent upon which auxiliary objective is used; for the A L 5 auxiliary objective the working distance is 100 ram. The diameter of the working field is altered by the combinations of lenses used; as the total magnification is increased, the field of view is decreased. Using the x l0 ocular lens and the A L 5 auxiliary objective lens the field size varies f r o m 41.7 mm. at x 5.4 total magnification to 9.4 ram. at x 24 total magnification (Table 1). THE T A B L E A N D FITTINGS
The table consists of an alloy f r a m e with a laminated w o o d e n top and shelves. T h e microscope stands are p e r m a n e n t l y fastened to the table-top, and the fibrelight tubes are attached to a metal bar which is fixed between the two microscope stands. The illumination box and the two z o o m control boxes are m o u n t e d on the middle shelf which has recesses for the operators' legs, enabling him to sit close to the table. T h e b o t t o m shelf is for the foot pedals which operate the motorised The Hand--Vol. 9
No. 1
1977
69
A n Inexpensive Z o o m Double Operating Microscope System M. J. Thompson, Christine M. Evans and R, W, Bl,amey
zoom and focus. The table legs have adjustable feet to aid stability. The electricity supply to the zoom and focus controls is aided by a six socket extension set fastened to one end of the table. DISCUSSION
The whole system was assembled for approximately s (in May 1976). The price of a comparable commercial system is approximately s The system we use contains many features which are available on the more expensive commercial operating microscopes: vision for both surgeon and assistant, and foot-pedal operated motorised zoom magnification and focussing. Fibre-optic lighting gives cold light, which avoids damage to tissues from heat. An adaptor enables a camera to be attached for photography. The advantage of two separately operated miscroscopes is that surgeon and assistant can use different magnifications when necessary. Permanent mounting of the microscopes confers stability. The table is light enough to be easily moved, and only one lead is needed to connect the six socket extension set to a power point. Laminated wood makes the system easy to clean. The table top is covered with towels to provide the necessary sterile operating surface. The microscopes do not need to be sterile, as once they are set up for the operation any further alternation to either zoom or focus is carried out by the foot pedals. Figure 4 shows the use of the microscope in hand surgery.
Fig. 4. The microscope in use for hand surgery.
70
The H a n d - - V o l . 9
No. 1
1977
AN INEXPENSIVE ZOOM DOUBLE OPERATING MICROSCOPE SYSTEM M. J. T H O M P S O N , C H R I S T I N E M. E V A N S and R. W. B L A M E Y , N o t t i n g h a m Microvascular surgery on small animals is useful in research, but commercial operating microscopes are expensive. The cheaper system which is described here has been used successfully in N o t t i n g h a m for microvascular surgery in small animals (renal transplantation in the rat, for example). It could easily be adapted for similar procedures in man, such as the replantation of severed digits. MATERIALS The equipment (Figs. 1 and 2) consists of two Nikon I SMZ-6 stereoscopic zoom microscopes with 30 ~ inclined eyepiece tubes, a Vickers 2 light source, two zoom control units, and a table with two shelves. There are thre e ocular lenses and three auxiliary objectives available, giving a total magnification range of x 5.4 to x 112. Personal requirements determine which combination of these lenses provides the best total magnification range (Table 1). The main objective lens provides a continuously variable magnification within the range x 0.9 to x 4, and this lens combined with the x 10 ocular lens and the AL5 auxiliary objective lens is ideal for procedures such as micro vascular anastomoses (Fig. 3); this is a total magnification range of x 5.4 to x 24.
Fig. 1. General view of equipment. R. W. Blarney, F.R.C.S., General Hospital, Nottingham, NGI 6HA. From the Dept. of Surgery University of Nottingham. The H a n d ~ V o l . 9
No. 1
1977
67
An Inexpensive Zoom Double Operating Microscope System M. 1. Thompson, Christine M. Evans and R. W. BI,amey
[3
C,
I1( i ... h
\ Fig. 2.
Specification of table. TABLE 1 T O T A L M A G N I F I C A T I O N S A N D W O R K I N G DISTANCES O B T A I N A B L E
Working Distance (rarn) Auxiliary objectives Objective
Magnification Eyepieces 10 x 15 x 20 x
77.5
100 AL5 (0.6 x)
85 AL7 (0.8 x)
45 A L 15 (1.4 x)
0.9 - 4.0 x 0.9 - 4.0 x 0.9 - 4.0 x 0.9 - 4.0 x Total Field Total Field Total Field Total Field mag. (mm) mag. (ram) mag. (mm) mag. (ram) 9.0-40.0 x 25.3 5.7 5.4-24.0x 41.7-9.4 7.2-32.0x 31.5-7.1 12.6- 56,0 x 18.0-4.0 13.5-60.0 x 13.3-3.0 8.I-36.0x 22.2-5.0 10.8-48.0x 16.7-3.8 18.9- 84.0 x 9.3-2.1 18.0-80.0 x 12.0-2.7 10.8-48.0x 20.0-4.5 14.4-64.0x 15.1-3.5 25.2-112.0x 8.4-1.9
Small motors are attached to the magnification and focussing controls of each microscope and are operated by foot pedals. Each microscope has one pair of foot pedals for operating the focussing motor, and one pair for operating the zoom ring motor which adjusts the total magnification. A camera can be mounted
on a special attachment
w h i c h fits o n a n e y e p i e c e
tube.
1. Nikon (Projectina, Ayrshire, England). 2. Vickers (York, England). I l l u m i n a t i o n is p r o v i d e d v i a a d u a l s t r a n d f i b r e - o p t i c s y s t e m , f r o m a v a r i a b l e i n t e n s i t y l i g h t - b o x ( V i c k e r s ) w h i c h u s e s a 12 v o l t , 50 w a t t , t u n g s t e n - h a l o g e n l a m p . T h i s g i v e s t w o c i r c u l a r b e a m s of c o l d l i g h t w i t h u n i f o r m l y b r i g h t fields, e a c h o f w h i c h c a n b e m a n o e u v r e d i n t o t h e b e s t p o s i t i o n . T h e w o r k i n g d i s t a n c e is d e p e n 68
The Hand--Vol. 9
No. 1
1977
An Inexpensive Zoom Double Operating Microscope System M. J. Thompson, Christine M. Evans and R. W. Blamey
Fig. 3. Anastomosis of renal vein in thc rat--magnification x 5.4. R ----Renal vein. S = Scoville-Lewis microvascular clamp. The rat renal vein is comparable in size (l-l.5mm) with a human digital artery at the level of the metacarpophalangeal joint. The width of this field is equivalent to 1.5cm. dent upon which auxiliary objective is used; for the A L 5 auxiliary objective the working distance is 100 ram. The diameter of the working field is altered by the combinations of lenses used; as the total magnification is increased, the field of view is decreased. Using the x l0 ocular lens and the A L 5 auxiliary objective lens the field size varies f r o m 41.7 mm. at x 5.4 total magnification to 9.4 ram. at x 24 total magnification (Table 1). THE T A B L E A N D FITTINGS
The table consists of an alloy f r a m e with a laminated w o o d e n top and shelves. T h e microscope stands are p e r m a n e n t l y fastened to the table-top, and the fibrelight tubes are attached to a metal bar which is fixed between the two microscope stands. The illumination box and the two z o o m control boxes are m o u n t e d on the middle shelf which has recesses for the operators' legs, enabling him to sit close to the table. T h e b o t t o m shelf is for the foot pedals which operate the motorised The Hand--Vol. 9
No. 1
1977
69
A n Inexpensive Z o o m Double Operating Microscope System M. J. Thompson, Christine M. Evans and R, W, Bl,amey
zoom and focus. The table legs have adjustable feet to aid stability. The electricity supply to the zoom and focus controls is aided by a six socket extension set fastened to one end of the table. DISCUSSION
The whole system was assembled for approximately s (in May 1976). The price of a comparable commercial system is approximately s The system we use contains many features which are available on the more expensive commercial operating microscopes: vision for both surgeon and assistant, and foot-pedal operated motorised zoom magnification and focussing. Fibre-optic lighting gives cold light, which avoids damage to tissues from heat. An adaptor enables a camera to be attached for photography. The advantage of two separately operated miscroscopes is that surgeon and assistant can use different magnifications when necessary. Permanent mounting of the microscopes confers stability. The table is light enough to be easily moved, and only one lead is needed to connect the six socket extension set to a power point. Laminated wood makes the system easy to clean. The table top is covered with towels to provide the necessary sterile operating surface. The microscopes do not need to be sterile, as once they are set up for the operation any further alternation to either zoom or focus is carried out by the foot pedals. Figure 4 shows the use of the microscope in hand surgery.
Fig. 4. The microscope in use for hand surgery.
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The H a n d - - V o l . 9
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1977
