Arrangement for removal of concretions from urinary tract

Claim 1

AN INSTRUMENT FOR THE REMOVAL OF CONCRETIONS FROM THE URINARY TRACT INCLUDING MEANS FOR INTRODUCTION INTO THE BLADDER AND THE URETER, A FLEXIBLE SONDE OPERABLY ASSOCIATED WITH SAID MEANS, SAID SONDE HAVING A DISCHARGE HEAD ADAPTED TO BE POSITIONED ADJACENT A CONCRETION, SAID DISCHARGE HEAD BEING DEFINED BY CONCENTRIC INNER AND OUTER ELECTRODE, SAID OUTER ELECTRODE HAVING AN ANNULAR END PORTION SURROUNDING THE INNER ELECTRODE WITH SAID ANNULAR END PORTION AND THE END OF THE INNER ELECTRODE BEING LOCATED AT THE SAME LEVEL, A FLEXIBLE CURRENT CONDUCTING ENVELOPE ENCASING SAID INNER ELECTRODE OPERABLY CONNECTED WITH THE OUTER ELECTRODE, A LAYER OF INSULATING MATERIAL BETWEEN THE CONDUCTING ENVELOPE AND THE INNER ELECTRODE, FLUID DELIVERY MEANS EXTENDING AXIALLY OF SAID SONDE AND HAVING AN OUTLET OPENING ADJACENT SAID DISCHARGE HEAD THROUGH WHICH FLUID IS DELIVERED INTO THE ZONE OF THE CONCRETION, MEANS OPERABLY CONNECTED WITH SAID INNER ELECTRODE AND ENVELOPE CONNECTED WITH SAID INCHARGES HAVING A VOLTAGE OF 5-30 KW. AND 700-1100 UA. CURRENT THEREBETWEEN WHICH IN CONJUNCTION WITH THE FLUID DELIVERED THROUGH SAID OUTLET OPENING DEVELOP AN ELECTRO-HYDRAULIC IMPACT FOR CRUSHING THE CONCRETION, AND MEANS FOR DELIVERING FLUID INTO THE ZONE OF THE CONCRETION.