PREPARATION OF RESIN CAST (KIDNEY, LUNGS & LIVER)

Question 1

Preparation of kidney casts
Day 1
What is used to ensure satisfactory casts?

Answer 1

FOR SATISFACTORY CASTS FRESHLY HARVESTED KIDNEY ARE USED.

Question 2

Dissection and washing procedure

Steps 1 & 2:

Answer 2

 REMOVED THE KIDNEYS WITH AS MUCH OF THE ABDOMINAL AORTA & INFERIOR VENA CAVA AS POSSIBLE. DISSECT THE LUMBAR ARTERIES CAREFULLY TO AVOID DAMAGE TO THE AORTA

 THE EN-BLOC IS WASHED THOROUGHLY WITH LUKE WARM TAP WATER

Question 3

Preparation of kidney casts

Step 3:

Answer 3

LIGATE THE LUMBER ARTERIES, CELIAC TRUNK, SUPERIOR MESENTERIC ARTERY AND OTHER LEAKAGES WHICH MIGHT HAVE OCCURRED DURING ITS REMOVAL

Question 4

Preparation of kidney casts

Step 4:

Answer 4

WATER IS INTRODUCED SEVERAL TIMES INTO MAJOR VESSELS AND URETERS TO REACH THE CORE OF THE KIDNEY AND THE KIDNEYS ARE GENTLY SQUEEZED TO REMOVE BLOOD REMAINS. THIS IS REPEATED ON SEVERAL OCCASIONS UNTIL THE EMERGING WATER IS FREE FROM TRACES OF BLOOD

Question 5

Preparation of kidney casts

Step 5:

Answer 5

HEREAFTER, THE KIDNEYS ARE SUBMERGED OVERNIGHT IN 3% FORMALIN. FORMALIN IS ALSO INJECTED INTO THE AORTA AND THE VENA CAVA

Question 6

Preparation of kidney casts
Day 2
Steps 1 & 2:

Answer 6

 THE EN-BLOC IS WARMED TO ABOUT 30°C

 THE EN-BLOC IS MOUNTED INTO A FRAME TO ASSUME ANATOMICAL POSITION

Question 7

Preparation of kidney casts
Day 2
Step 3:

Answer 7

 RESIN IS INJECTED:
 200 ml blue resin injected into inferior vena cava (set and hardens after 20 min)

 100 ml red resin is injected into aorta (set and harden after 30 min)

 50ml yellow resin is injected in each ureter (set and hardens after 24-48 hrs)

Question 8

PREPARATION OF KIDNEY CASTS
 ONCE THE SPECIMEN HARDENS:
Steps 1 & 2:

Answer 8

 SUBMERGE AND LEAVE IN CONCENTRATED HYDROCHLORIC ACID FOR A PERIOD OF 3 - 5 DAYS FOR MACERATION

 THE CAST THUS FORMED IS MOUNTED ON THE TRIPOD STAND AND IS SUBJECT TO STRONG JETS OF COLD TAP WATER

Question 9

ONCE THE SPECIMEN HARDENS:

Step 3:

Answer 9

EXCESS TISSUE AND CAST IS WASHED OFF AND CAST ALLOWED TO DRY

Question 10

ONCE THE SPECIMEN HARDENS

Step 4:

Answer 10

WHEN THOROUGHLY DRY, A GENTLE SPRAY OF CLEAR LACQUER MAY BE USED TO ENHANCE COLOUR AND GET RID OF RESIDUAL DEPOSITS WHICH MAY APPEAR DURING MACERATION

Question 11

PREPARATION OF BRONCHIAL TREE CAST
 DAY 1
How are satisfactory casts achieved?

Answer 11

FOR SATISFACTORY CASTS FRESHLY HARVESTED PAIR OF LUNGS ARE USED

Question 12

PREPARATION OF BRONCHIAL TREE CAST
 DAY 1 :
Steps 1 & 2:

Answer 12

 THE TRACHEA IS CANNULATED AND LUKE WARM, DE-AERATED WATER IS INTRODUCED INTO THE TRACHEA AND GENTLY MASSAGED OUT SEVERAL TIMES

 5% SODIUM BICARBONATE MAY BE INJECTED AS WELL IF THERE IS SUSPECT OF ABUNDANT MUCUS ACCUMULATION WHICH ALSO IS SQUEEZED OUT

Question 13

PREPARATION OF BRONCHIAL TREE CAST
 DAY 1 :
Steps 3 & 4:

Answer 13

 LUNGS ARE EXPANDED SEVERAL TIMES WITH CARBON DIOXIDE GAS FROM A CYLINDER

 THE LUNGS ARE PLACED IN A DEEP SINK AND 70% ALCOHOL IS INTRODUCED THROUGH THE TRACHEA AND LEFT THERE OVERNIGHT

Question 14

PREPARATION OF BRONCHIAL TREE CAST
 DAY 2
Step 1:

Answer 14

USING A TRIPOD STAND THE LUNGS ARE REMOVED FROM ALCOHOL AND IMMERSED IN WARM DE-AERATED WATER UNTIL THERE ARE NO TRACES OF ALCOHOL

Question 15

PREPARATION OF BRONCHIAL TREE CAST
 DAY 2
Steps 1 & 2:

Answer 15

 12% GALATIN IS PREPARED IN WARM WATER AND LUNGS ARE FILLED WITH
THIS SOLUTION ASCERTAING PROPER EXPANSION OF THE LUNGS
 THE LUNGS A SET TO ASSUME ANATOMIC POSITION

Question 16

PREPARATION OF BRONCHIAL TREE CAST
 DAY 2
Step 4:

Answer 16

6 LITERS OF WARM (26°C) GREEN RESIN IS INJECTED INTO THE TRACHEA.
EVIDENCE OF INJECTION MAY BE SEEN AS THE GELATIN OOZES OUT OF THE PLEURA AND A GREEN TINGE APPEARS ON THE SURFACE OF THE LUNGS

Question 17

PREPARATION OF BRONCHIAL TREE CAST
 DAY 2
Step 5:

Answer 17

LEAVE FOR 36-48hrs TO SET AND HARDEN

Question 18

PREPARATION OF BRONCHIAL TREE CAST
 ONCE THE SPECIMEN HAS HARDEN:
Steps 1 & 2:

Answer 18

 THE LUNGS ARE MACERATED IN HYDROCHLORIC ACID (HCl) FOR 8-10 days

 THE BROCHIAL TREE CAST FORMED IS REMOVED FROM THE HCl AND SUBJECTED TO STRONG JETS OF TAP WATER AND LEFT TO DRY

Question 19

PREPARATION OF BRONCHIAL TREE CAST
 ONCE THE SPECIMEN HAS HARDEN
Steps 3 & 4:

Answer 19

 A CLEAR LACQUER IS SPRAYED TO ENHANCE COLOUR

 LUNGS ARE READY FOR MUSEUM MOUNTING

Question 20

PRERATION OF LIVER CAST
DAY 1
How to achieve satisfactory casts?

Answer 20

FOR SATISFACTORY CASTS FRESHLY HARVESTED LIVER IS USED

Question 21

PRERATION OF LIVER CAST
DAY 1
Steps 1 & 2:

Answer 21

 LIVER IS HARVESTED WITH AS MUCH OF THE INFERIOR VENA CAVA AS POSSIBLE

 LIVER IS WASHED SEVERAL TIMES WITH LUKE WARM WATER INTO IVC, PORTAL VEIN, COMMON BILE AND HEPATIC ARTERY

Question 22

PRERATION OF LIVER CAST
DAY 1
Steps 3 - 5:

Answer 22

 THE GALLBLADDER IS FILLED WITH WATER AND GENTLE SQUEEZED OUT

 CANNULATE ALL VESSELS FOLLOWING WASHING PROCESS

 3% FORMALIN IS INJECTED IN ALL VESSELS AND LIVER LEFT OVERNIGHT IN 3% FORMALIN SOLUTION

Question 23

PRERATION OF LIVER CAST
 DAY 2
Step 1:

Answer 23

THE LIVER IS POSITIONED IN AN ANATOMICAL POSITION

Question 24

PRERATION OF LIVER CAST
 DAY 2
Step 2:

Answer 24

 RESIN INJECTION :
 Yellow resin solution is injected in the gallbladder
 Red resin solution is injected into the arteries
 Blue resin solution is injected into hepatic vein
 Purple resin solution is injected into portal vein
 The resin set and hardens after 36 hrs

Question 25

PRERATION OF LIVER CAST
 DAY 2
Step 3:

Answer 25

 LIVER IS SUBMERGED IN HCl FOR MACERATION, 7-9 days

Question 26

PRERATION OF LIVER CAST
 DAY 2
Steps 4 & 5:

Answer 26

 THE PREPARED CAST IS CLAMPED ON A TRIPOD LABORATORY STAND AND IS SUBJECTED TO STRONG JETS OF WATER. THIS IS CONTINUED UNTIL ALL MACERATED TISSUE, SOFT TISSUE AND RESIN REMAINS ARE REMOVED

 LEAVE FOR DRYING