The next time you use a GPS to mark a favorite fishing hole, you are using the same electromagnetic principles that power the inReach ™ System (superDimension, Inc.) of guided bronchoscopy, used for guided navigation to peripheral lung lesions beyond the reach of traditional scopes, as well as for locating and staging suspect lymph nodes in the surrounding mediastinum.

 

Dr. Gary Guidry, pulmonologist, explains, “Visual examination of the bronchial tree can be done to only the fourth  or fifth larger bronchial divisions and then gets increasingly smaller, and the bronchoscope can no longer advance. At the periphery of the lungs, biopsy forceps are not steerable and you may not even get near the lesion. But the inReach continues past that point and we can actually steer the device, turn it, angle it and go down different bronchii to reach smaller, distant locations.” 

 

It has also changed the safety of lung lesion biopsies, going from as high as a 50 percent possibility of pneumothorax during more a conventional transthoracic CT needle biopsy going thru the patient’s back or chest wall, to almost zero incidence with the minimally-invasive inReach.

 

“The occurrence of pneumothorax drops to about 2 percent using the inReach during lung procedures, and since Lafayette General Medical Center acquired it in October 2009, it hasn’t happened once,” added Guidry.

 

And this new technology is useful in situations of ‘watchful waiting.’ In the past, after multiple CT scans over time showed growth of lesions, they were resected and often turned out to be benign. “You’re glad that they’re benign, yet the patient has undergone a major surgery they didn’t have to have. This will help to eliminate that practice and get an earlier diagnosis,” he said.

 

 Guidry is one of the first three physicians to use the inReach in Louisiana, doing ten cases by the end of 2009 at Lafayette General, and they have another physician in training on the device. 

 

“The huge advantage of this InReach system as regards its utility in our everyday practice is that now it allows us to more than double our diagnostic capability in small peripheral lung lesions, and done much safer as compared to CT needle biopsy,” Guidry added.

 

This technology is like ‘a miniature GPS’ where the entire route to the lung lesion is planned three-dimensionally by the software from prior CT scans allowing the physician to get to the lesion via a real-time procedure.

 

The patient is sedated and placed on a table topped with a plate creating a low-frequency, electromagnetic field with the inReach equipment and its viewing screen positioned alongside. No beepers or cell phones are allowed in the room. “Pacemakers and implants are not supposed to affect it, but the manufacturer’s representative needs to be there, and I would proceed with caution,” stated Guidry.

 

After registration of the ‘roadmap’ to the patient’s anatomy, a set of two catheters, a small one inside the other, equipped with a sensor is inserted in the bronchoscopy tube. When the main catheter can go no further in the lung, the small catheter set continues on through the bronchial tree, tracked electromagnetically to the sensor. The final target is reached with the physician externally manipulating, guiding and fine-tuning it in different directions 360°, and as far out as the pleura.

 

When the destination is reached, the navigation catheter is removed and the guide catheter is locked and becomes a channel through which biopsy and other endobronchial instruments are threaded to and from the site.

 

Enlarged lymph nodes lying on the opposite, unseen, side of the bronchial walls are automatically marked with a small dent as the catheter/sensor moves thru the lung. A needle positioned at the ‘dent’ goes through the wall and aspirates material from the node, which is brought up for exam.

 

A pathologist is standing by for immediate tissue and frozen section reading, which will guide the physician on what may possibly happen next: fiducial marker placement for radiation therapy, or dye marking of the lesion for easier viewing for video-assisted thoracoscopic surgery (VATS).

 

If it is determined by diagnosis at biopsy that conventional radiation therapy or stereotactic radiosurgery will be done, the pulmonologist places tiny gold markers or fiducials around the lesion or within it, for subsequent tracking purposes. In the past, the marker placement was sometimes a second procedure done at a different time, but now it can be combined with the inReach procedure all in the same session.

 

“I had an older male patient who told me that if during biopsy he had lung cancer, he didn’t want surgery. We did a navigated inReach and got a biopsy of the lesion; the pathologist said it was malignant, and I placed fiducials for radiosurgery – all in a matter of 40 minutes,” said Guidry. 

 

Dr. Brent Mahoney, radiation oncologist at CyberKnife Center at Lafayette General, “There is a long history of fiducial use in radiation oncology in different areas of the body, and is generally the preferred way of localizing lung tumors: they can always be seen on x-ray and they move with the tumor. If Dr. Guidry thinks at the time of his procedure that the patient has the potential for radiation, he drops the fiducials at that time; I’m just the benefactor of his work. 

“Hopefully, the inReach will improve the rate of false-negatives because of the difficulty of reaching peripheral lung tumors and getting correct tissue samples in the past. However, the safety of this procedure with no pneumothorax is the big thing,” he continued.

 

The inReach system is used in five locations in Louisiana: Lafayette General Medical Center, Opelousas General Hospital, St Tammany Parish Hospital-Covington, East Jefferson General Hospital-Metairie, and Tulane University Hospital and Clinic-New Orleans.