Fusion

The unique 3D plan­ning soft­ware EndoSize¹ supports Prof. Dr. Kaladji in his routine to this day. It enables the digital plan­ning of mini­mally inva­sive vascular sur­geries on a desk­top computer or lap­top. The plans are then stored in the hospi­tal’s imag­ing and com­mu­ni­ca­tion sys­tem or on a USB stick for later use in the OR. In addi­tion to deter­mining the appro­priate stents and C-arm angles for rele­vant imag­ing dur­ing sur­gery, the CT image acquired for diag­nostic pur­poses can also be pro­cessed by the soft­ware. For example, the areas that need repair in the ves­sels, such as aneu­rysms, ste­noses, and block­ages can be marked.

Adja­cent ves­sel out­lets can also be regis­tered so that they are not blocked with stents dur­ing surrgery. These mark­ings sup­port the sur­geon dur­ing the oper­a­tion because the pro­cessed image, including the markings, can be super­imposed on the live image taken by the C-arm with the aid of the EndoNaut² of the mobile Therenva sys­tem. It shows the physi­cian where in the vessel the inter­vention is to take place. According to Prof. Dr. Kaladji, this pro­cedure has advan­tages above all for the patient: “You have planned the inter­vention in advance. This helps especially with FEVAR and EVAR inter­ventions. Without this option, we had to use more con­trast agent and needed more images, which also led to a higher dose. At that time, for example, we didn’t know which per­spec­tive would produce the best view of the problem area. We had to improvise a lot more.”

Today, Prof. Dr. Kaladji heads the Depart­ment of Thoracic, Cardiac and Vascular Surgery at the Center for Cardi­ol­ogy and Pneu­mol­ogy at the Univer­sity Hospital in Rennes with his col­leagues. More than 2,000 vascular sur­geries are per­formed there each year. Prof. Dr. Kaladji is an inter­nationally-­recognized expert in his field. The vascular surgeon operates as precisely and care­fully as pos­sible during each oper­ation. And intra­operative imaging helps him.

For this, he uses the Ziehm Vision RFD Hybrid Edition³ CMOSline⁴ – its images impressed him from the begin­ning. Prof. Dr. Kaladji sees the signif­i­cantly lower invest­ment costs com­pared to a fixed sys­tem, and in the ease of oper­a­tion as addi­tional meaning­ful advan­tages of the mobile C‑arm. The sys­tem just needs to be con­nected to the power sup­ply in the OR and is imme­di­ately ready to use. In addi­tion, its mobility allows the OR set­up to be changed dur­ing the pro­ce­dure, if neces­sary, thereby enabling more flexi­bility in the OR work­flow than a per­ma­nently installed sys­tem. He uses the C‑arm with Therenva’s EndoSize and EndoNaut sys­tems. This enables the trans­feral of the pre-planned sur­gical data to the live image acquired with the C‑arm. In addi­tion, real-time visual­iza­tion of the instru­ments can be over­laid on the cur­rent patient images. The deci­sive fac­tor is always the image qual­ity of the fluo­ro­scopic images of the C‑arm. The sharper the images and the more clearly the con­tours are dis­played, the better the results deliv­ered by the image fusion of the C‑arm 2D images with the EndoSize 3D images.

Today, Prof. Dr. Kaladji and his team are sched­uled to revas­cu­lar­ize a side branch of an aorta. The open­ing of such vas­cu­lar occlu­sions is one of the stan­dard pro­ce­dures that Prof. Dr. Kaladji has been per­form­ing at the Univer­sity Hospital in Rennes for more than ten years. After enter­ing the oper­ating room, the first thing Prof. Dr. Kaladji does is con­nect his USB stick to the EndoNaut. This is how he accesses and dis­plays the EndoSize plan­ning data on the screens of the Therenva sys­tem. In the next step, he uses the Ziehm Vision RFD Hybrid Edition CMOSline to see the loca­tions of the ves­sel occlu­sions that he already saw on the CT image. He then starts the regis­tra­tion process, in which the CT image auto­mat­ically adapts to the sec­tion of the live image. As soon as Prof. Dr. Kaladji con­firms the image fusion on the EndoNaut touch panel, a blue ves­sel over­lay including the points marked in EndoSize is dis­played on the live image. To ensure that the vessel over­lay is dis­played in the cor­rect loca­tion, Prof. Dr. Kaladji per­forms a con­trol angi­og­raphy with a small amount of con­trast agent using the C‑arm. Once he is sat­is­fied with the posi­tion of the over­lay, he can place the stents at the marked loca­tions. He uses the Ziehm Vision RFD Hybrid Edition CMOSline to moni­tor pro­gress. Once the stents are placed, Prof. Dr. Kaladji checks the result at the end of the pro­ce­dure with the C‑arm.

The com­bi­na­tion of pre-planned sur­gi­cal data and its fusion with live images dur­ing sur­gery is a tremen­dous advance in medi­cal imag­ing for the vascu­lar sur­geon. “Before the com­bi­na­tion of Ziehm Imaging and Therenva sys­tems, we were well-acquainted with the really good imag­ing and intu­i­tive han­dling of Ziehm’s mobile C‑arm for sur­geons. Now we are reap­ing the bene­fits of being able to com­bine world-class 2D imag­ing with a 3D imag­ing envi­ron­ment. We have used many dif­fer­ent C‑arms, but Ziehm Imaging’s mobile C‑arm was the best even before we started using it with Therenva’s EndoNaut. And EndoNaut is very help­ful for sur­geons. The systems com­ple­ment each other per­fectly.”

Prof. Dr. Kaladji sees the advan­tages of image fusion for other fields as well: “In the future, image fusion will also be impor­tant for car­di­ol­o­gists, especially for TAVI inter­ven­tions, for example,” says Prof. Dr. Kaladji. TAVI stands for ‘trans­catheter aortic valve implan­ta­tion.’ In this proce­dure, the biolog­i­cal heart valve pros­thesis is implan­ted using a mini­mally inva­sive method. Prof. Dr. Kaladji is con­vinced “that image fusion will be as use­ful to sur­geons in car­di­ol­ogy as it is to me in vascular surgery.”