Ureteroscopy: Background and Current Controversies

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MINIMALLY INVASIVE STONE SURGERY (Ureteroscopy)

(Images of surgical equipment featured in this article are for patient education only. They are not intended for promotional use or a reflection of personal preference. We accept no fees or other benefits from vendors or their agents.)

Evolution of Technique

The fascinating history of urology with its captivating depictions, texts and stories rivals any other field in medicine. In particular, the ancient past of lithotomy (treatment and removal of urinary stones) dates back to Mesopotamia (3200 BC)and descriptions and treatments for urinary stone disease have been identified from ancient cultures including Hindu, Greek, and Egyptian. The treatment of stones, which at the time most commonly occurred in the bladder, was very dangerous, often lethal.  As such, it led to the development of one of the first medical subspecialists, the lithotomist, who opened the urinary tract and removed stones directly. Recognition of this unique set of skills earned a distinction in the Hippocratic oath, still recited by graduating students: “I will not cut for the stone, but will leave this to be done by practitioners of this work…”

Today, “cutting for stone,” otherwise known as open stone surgery, has been replaced by alternative minimally invasive techniques. Critical to this change has been the introduction of the endoscope. Whereas early pioneers such as Howard Kelly (depicted above in the early 1900’s using a wax tipped catheter in the ureter to detect a ureteral stone) relied heavily on intuition, feel, and clinical suspicion, advances in endoscopy have made it possible to inspect all parts of the urinary tract directly.Screen Shot 2016-01-19 at 1.56.38 PM

The particular endoscope that has revolutionized our ability to treat kidney stones in a minimally invasive fashion is the ureteroscope. Incorporation of its use into urologic practice has led to the development of a unique subspecialty, endourology, that focuses on minimally invasive and endoscopic surgical treatments.

Modern Ureteroscopy

A ureteroscope, as its name implies, is an endoscope designed to visualize and work within the ureter. Other scopes commonly used by urologists and endourologists include the cystoscope (used in the bladder) and the nephroscope (used in the kidney).

Although such scopes now enable modern surgical stone treatment, they have only been routinely utilized for the past several decades. Minimally invasive kidney stone treatment began in the mid-1980’s with shock wave lithotripsy and percutaneous nephrolithotomy. Ureteroscopy for treatment of ureteral stones was not performed routinely until then as well, and it was not until the late 1990’s and early 2000’s that ureteroscopes could routinely access and treat stones in the kidney. In the United States we often take such technologies and treatment options for granted, but open stone surgery is still practiced in many parts of the world where modern technology remains limited.

There are two types of ureteroscopes, rigid and flexible. Rigid ureteroscopes, as their name implies, are firm and preferred for treatment of stones lodged in the lower ureter which can usually be accessed in a straight path. When stones are located in the upper ureter and/or kidney, they often require Screen Shot 2016-01-19 at 2.09.57 PM
flexible ureteroscopes that accommodate to the shape of the ureter and renal collecting system (figure on right).  Though more difficult to maneuver, flexible scopes allow the urologist to inspect nearly the entirety of the inner kidney to find stones, treat them, and remove them using a variety of techniques. Innovation this area is brisk and modern digital ureteroscopes offer increasingly superior image quality, lighting and wide fields of view.

Fiberoptic vs. Digital URS

(Figure – Left ) Ureteroscopic image of the renal collecting system using older generation fiberoptic ureteroscope (left) and newer generation digital ureteroscope (right).  Note the superior image quality, increased light intensity and wider field of view.  Panels A and B feature small stones attached to a renal papilla.  Panels C and D feature the endoscopic appearance of Randall’s plaque.

 

Irrigation and Access Sheaths

In order visualize anything at all, fluid must run continuously through the scope and into the kidney to wash away blood, debris, and crystals that impair visualization. To accomplish this, the fluid (most commonly saline) is hung from a bag and run through tubing directly into the body of the scope where it comes out the tip and into the kidney.

This inflow is harmless, but excess filling of the kidney because of high pressure inflow or an inability of the fluid to freely exit around the scope can overstretch the kidney and cause fluid absorption, leakage, bleeding, and small tears within the kidney itself, a term we call extravasation.

To prevent this, many urologists use a device called a ureteral access sheath. This can be thought of as a temporary tunnel from the bladder to the kidney which allows any fluid that is irrigated into the kidney to quickly wash out around the scope, optimizing visualization and decreasing the likelihood of extravasation. The scope can be passed back and forth without rubbing against and potentially damaging the lining of the ureter, which is generally around the same small diameter as the scope itself. When used appropriately, temporary sheaths are safe and decrease postoperative infections and sepsis. While the majority of urologists routinely use them during ureteroscopy, debate does exist within the community as to whether or not they are required in every case.

Screen Shot 2016-01-20 at 11.41.49 PM(Figure on Left – Boston Scientific Navigator HD TM, Marlborough, MA)

The concern with routine use of a sheath is trauma and injury to the ureter when the sheath is passed. Larger diameter sheaths are preferable for procedures, but the ureter is quite narrow and often will not accommodate a large sheath and sometimes any sheath at all. In such cases, surgeons have several options.  If they deem a sheath necessary, they can place a temporary ureteral stent that lets the ureter passively dilate and facilitate sheath placement at a later time. Alternatively, they can dilate the ureter during the procedure using either balloon or serial dilators in order to get the sheath up.

Screen Shot 2016-01-29 at 10.07.22 AM

(The ureteral access sheath (white arrow) is passed under fluoroscopic guidance over a wire (black arrow) that is positioned from outside the body and extends through the ureter to the kidney.)

Because the ureter is delicate and easily torn and injured when overstretched, there is risk.  In a recent publication by Traxer et al. that describes 359 consecutive cases of ureteroscopy where a ureteral access sheath was used, nearly half (46.5%) of the patients had some degree of ureteral injury. Most injuries were superficial, but severe injuries were found in 13.3%. The main figure (below) from this paper often presented at society meetings, particularly by those who do not favor sheath use.

Screen Shot 2016-01-20 at 11.27.46 PM

While these images raise concerns, there is no evidence to date that when managed properly with placement of a temporary ureteral stent these injuries produce any long term consequence. For example, there is no published evidence of an association between ureteral access sheath use and ureteral stricture. Most studies have shown that intraoperative complication rates during flexible ureteroscopy are no different with or without an access sheath.

Alternatively, urologists have the option of performing ureteroscopy without using a sheath at all.  One advantage of this approach is that the ureteroscopes themselves are thinner than the sheaths and thus more likely to be able to be passed up the naturally thin ureter without trauma or need for dilation.  This approach does have limitations though including poorer visualization, higher potential for excess intrarenal pressure, and a limited ability to make multiple passes back and forth between the kidney and bladder to remove stones.

Lasers and Baskets

Many instruments, all are extremely thin, can be passed through the small working channel that runs from the back of the ureteroscope outside of the body, to the tip of the scope in the kidney. They are used to fragment and remove stones.

Stone retrieval baskets, pictured below, (Cook Medical, Bloomington, IN) are opened and closed by an assistant to ensnare stones and remove them from the kidney. They come in various shapes, sizes and configurations. When stones are roughly 2-4 mm the basket is able to remove them intact.  When stones are larger, they must be fragmented into smaller pieces in order to be removed or pass.

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The most commonly utilized method to fragment stones during ureteroscopy is laser lithotripsy.  Several lasers exist for the purpose but the most popular one by far is the Holmium laser. The Holmium laser can safely fragment any type of stone. The laser delivers short bursts of light energy through water that destroys the stone’s structure by creating a micro explosion of intense heat, pressure, and cavitation bubbles. Because the laser energy penetrates less than half of a millimeter deep it causes minimal damage to surrounding tissues.

Screen Shot 2016-01-21 at 12.59.51 PM

(Dornier Medtech, Friedrichshafen, Germany)

Ureteroscopic Stone Treatment Techniques

As ureteroscopic technology and familiarity with this approach to treat stones continues to grow, the relative number of stones being treated in this fashion has been growing rapidly as well. The latest estimates of surgical practice from the past decade show that ureteroscopy has replaced shock wave lithotripsy as the most commonly performed treatment of kidney stones, accounting for 54% of upper urinary tract stone procedures. Along with the widespread adoption of this procedure, two main techniques have evolved into practice, the optimal one of which remains unclear.

Active Extraction

Active extraction means to remove every piece of stone from the kidney so that at the end of the procedure there are no remaining stones and patients do not pass any stones postoperatively. Critics raise concerns that this technique requires a ureteral access sheath, an assistant to operate the basket, and potentially increases the operating time. A video description of this technique prepared for this article can be seen below.

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Stone Dusting

Stone dusting is conceptually different from active extraction because the goal of the procedure is not to remove all stones directly but rather fragment them into minute pieces (dust) that can then be passed after the procedure, painlessly and without consequence.

Because his technique needs no access sheath, being performed with single pass of the ureteroscope, it benefits patients with narrow ureters.  The surgeon can dust with only a laser and avoid a basket with its cost of disposable equipment and need for a skilled assistant. Here is a video of the procedure prepared by Lumenis Ltd, Israel.

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Which Technique is Best?

Urologists debate whether active extraction or dusting is the better treatment approach, and both sides have their staunch advocates. As is common, the intensity of debate reflects the paucity of studies that compare the two techniques.

Interim results from an ongoing study by the Endourology Disease Group for Excellence (EDGE) comparing dusting to active extraction (table) indicate that dusting is associated with a shorter operative time (40.5 vs. 59.8 min) despite being used to treat larger stones (113 mm2 vs 81mm2).

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On the other hand, a greater percentage of patients treated with a dusting had residual (leftover) stones after the procedure than those treated using active extraction (39.1% vs 11.1%).

These residual stones were not just dust; 44% of the stones were greater than 4 mm.

Despite the higher rate of residual fragments in the dusting group, only one patient in each arm suffered symptoms from a residual fragment at short term follow-up, raising the question of whether or not small residual stones are clinically significant.

But these clinically insignificant residual fragments (CIRFs)’ may not be clinically insignificant.

In one recent study, the EDGE working group found that 44% of 232 patients who had ureteroscopic stone treatment and were found to have residual fragments experienced a “stone event” (defined as a composite of stone growth (at least 1 mm), stone passage, re-intervention or postoperative complications) at mean follow-up of nearly 17 months. Of these 29% required a surgical intervention.

The likelihood of stone events and reintervention were depended on the size of the residual fragment. Among patients with fragments greater than 4mm, reintervention was required 38% of the time and complications related to the fragment occurred 59% of the time. Second surgical procedures occurred sooner in patients treated with a dusting technique compared to those treated with active extraction but the statistical significance of this difference was uncertain.

Portis et al. found that among 218 patients treated with ureteroscopy and active extraction residual stones predicted need for retreatment. At a median follow-up of 4.1 years, patients with residual fragments less than 2mm in size required retreatment 2.4% of the time, compared to 19% among patients with residual fragments 2 to 4 mm in size, and 46% among patients with residual fragment greater than 4mm. Rebuck et al. found a nearly 20% likelihood of retreatment for residual fragments less than 4 mm after ureteroscopy at a mean of 1.6 years.

All in all, both sides in the debate can find reasons for their position. Active extraction leaves behind fewer fragments, but so far in a head to head trial need for less secondary surgery has not been documented. Dusting avoids the cost and complexity of the basket and the sheath, but in the long term may condemn patients to more followup surgery. Time and trial will tell, ultimately.

Follow-Up After Ureteroscopy

Oftentimes urologists will leave a temporary ureteral stent to prevent swelling of the ureter as a result of the procedure. This use of stents is a source of controversy worthy of a future post.

All agree one needs follow-up imaging of the kidneys to tell whether or not stones have been fully removed and whether or not a ureteral stricture (scar) has caused obstruction and  kidney swelling (hydronephrosis), a complication that occurs 1-4% of the time.

Ultrasound Imaging

Ultrasound is relatively inexpensive, requires no radiation, and offers very detailed images of the kidney to determine whether or not there is hydronephrosis. But it is not very accurate at identifying residual stones, particularly small ones. It is also operator dependent and results can vary based upon the experience of the sonographer performing the examination.

KUB X-Rays

Ultrasounds are commonly combined with a kidney x-ray (commonly referred to as a KUB) which is also inexpensive and better at detecting stones with minimal radiation.The majority of published studies to date that have assessed stone free rate after ureterscopy have used KUB/US to determine the presence of residual fragments. Stone free rates using this imaging endpoint are commonly found to be in the mid 80-90%; even for large stones greater than 2 cm in size.  

CT Scans

CT scans are the best test to identify stones, but are more expensive and are associated with higher degrees of radiation. Those studies that have used postoperative CT scans to identify residual stones demonstrate much lower stone free rates, commonly in the range of 50%.  Interestingly the difference appears to be in the small stones <4 mm more likely to be seen on CT scan over KUB/US. If these stones are not taken into consideration, CT scan follow-up would otherwise be on par with that reported in the KUB/US series.

Although the question of whether KUB/US or CT is a better follow-up test is an important one, the more important question is whether or not routine imaging is being performed after the procedure at all. Despite recommendations by the American Urological Association that all patients should undergo at least a minimum of an ultrasound after ureteroscopy (see figure below) ,a recent study from the Cleveland Clinic found that fewer than half of all urologists routinely obtain any postoperative imaging whatsoever.

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Take Away Messages

The goal of ureteroscopy should be to render the patient stone free 

Regardless of the technique used, the ultimate goal of the procedure should be to leave the patient with no stones. Residual fragments are likely sources of future stone events. Therefore removing all stones should improve long term outcomes.

Urologists should be familiar with all ureteroscopic treatment techniques

Results of studies such as the EDGE group comparing dusting and extraction will determine the gold standard ureteroscopic treatment technique. In all likelihood though, we will come to realize that ureteral anatomy, width, and ability to pass an access sheath as well as the stone themselves will mandate one technique over another for any one patient.

Soft stones, for example, are more likely to fragment to true dust and thus may be more amenable to dusting. Harder stones are more likely to fragment into large pieces and thus benefit from active removal. Infection mandates complete stone removal, potentially harder to achieve with dusting. Alternatively dusting does not require an assistant and thus may be the only feasible option in instances where extra help is not available.

The ureteroscopy should not be the end of the story

Nephrolithiasis often manifests as an acute event ending in ureteroscopy; however, it is increasingly recognized as a chronic condition. As such, it is critical that surgery to remove the stone is not the end of the relationship with the patient.

Residual stones commonly lead to clinical events greater than one year from the time of the initial procedure including growth, passage, and need for retreatment.

Stone disease is chronic and recurrent, and the least desired outcome is formation of new stones after stones have been removed. As many as 50% of first time stone formers will recur within 10 years highlighting the significance and potential benefits to dietary counseling, metabolic testing, surveillance imaging, and other practices to prevent and detect stones over the long-run.

The main thrust of this entire site is toward prevention, before surgery is ever needed and with especial need after a successful surgery so that another need never be performed.

56 Responses to “Ureteroscopy: Background and Current Controversies”

  1. JPD

    I had a ureteroscopy with laser 12 days ago. Doctor said they had to blast the stone first ( 5mm x 4 mm) and remove the pieces. This was my 2nd ureteroscopy as my first was 6 years ago from which I had a quick recovery. This time I am having a MUCH tougher time. Stent was removed after two days which was the most painful and horrifying two minutes of my life and I have been through 40 stones in my life so I know pain well. Since then, I have periodic but brief sharp pain when sitting on hard surface or bending over. Also have pain every single night for last 10 days when the area of the surgery “wakes up and stretches out”. Any attempt at activity with my wife is also painful. My urologist last week just said “give it time” and I should be fine. Is such pain normal for some patients or should I see a new urolologist ? I’m fearful of this never healing if something happened during surgery.

    Reply
    • Fredric Coe, MD

      Hi, I suspect your urologist is right and things will gradually heal up. But 40 stones is so many, you should really push at prevention. If you have not seen it, here is a good plan. You should not need to make so many stones – even any is too much. Regards, Fred Coe

      Reply
  2. Raquel D

    Thank you, Dr. Coe. So what might that mean for my diet? Any specific plan I should adhere to at this point?

    Reply
    • Fredric Coe, MD

      Hi Raquel, As I remember your lab data results were normal and it seemed your stones might have formed in the past. I would have a new 24 hour urine when you are recovered from surgery and of course have the removed stones analysed. If results of the urine remain normal merely maintain a high fluid intake. But it is your physician who is in charge and what I say is from a great distance and merely commentary. Regards, Fred Coe

      Reply
  3. Nihal

    Dear Dr. Coe,

    So on the Feb 28 reply, you had recommended I do a 24 hour urine to check my pH (among other things). My urologist says he will order 24 hour urine, only after surgery. I would like to see if I can melt this before doing any surgery, because my average HU densities are 350 and 450 HU (see earlier post) and my home pH measurements are below 5.5. So I got my family Dr. to order the 24 hour urines. I have some doubts as to whether he ordered the right ones to get all the info that is needed for a full evaluation. Following are the tests he ordered. Can you confirm that this covers everything including pH, SS values, and any other data that is needed for a full evaluation for any kind of stone? If these are not the right ones what should he have ordered? I would appreciate if you can respond quickly since I would like to start the collection process as soon as possible. I am in Illinois USA.

    1. UR 24 hour Calcium
    2. UR, oxalate 24 hour, MAYO OXU
    3. UR 24 hour uric acid QUANT
    4. UR 24 hour creatinine

    Thanks
    Nihal

    Reply
    • Fredric Coe, MD

      Hi Nihal, No they are not related to uric acid stones as there is no pH. Likewise, most physicians order kidney stone panels – complete arrays of testing that bundle pricing so as to get the most from what you pay. Quest and LabCorp offer these. You do not know the stone type either, because HU are only approximate. More: I am far from your care as I know nothing except what you have sent, and I fear becoming an intruder. Might I recommend that before the surgery you seek a second opinion at a recognized university based kidney specialty program, just to be sure of everything. Regards, Fred Coe

      Reply
      • Nihal

        Dear Dr. Coe,

        Thanks for the response. Is the following the right test from Labcorp?
        http://www.labcorp.com/test-menu/30091/kidney-stone-urine-test-combination-with-saturation-calculations

        With regard to a recognized university based kidney specialty program, would you be able to recommend a Dr. in the Bloomington, IL, Decatur, IL, Peoria, IL, Champaign/Urbana, IL, Peoria, IL, Springfield IL. areas?

        Thanks
        Nihal

        Reply
        • Fredric Coe, MD

          Hi Nihal, If it is LabCorp you want their Litholink product. It is more polished and priced the same. I looked on the map and you live in an unfortunate place. You are about equal distance – and considerable – from our center in Chicago and the other center in Indianapolis – but the INDY one looks easier to get to. One or the other would be right for you. If it is INDY, let me know and I can help make an introduction. If Chicago is not too hard, the same. Regards, Fred Coe

          Reply
          • Nihal

            Dear Dr. Coe,

            Actually Chicago is closer to me. Whom do I contact to setup something? Do I get to see you or someone else? As you might understand, I would have to investigate the affordability, since I am pretty sure my insurance won’t cover the bulk of it, since you would be considered “out of network”.

            Thanks
            Nihal

            Reply
            • Fredric Coe, MD

              Hi Nihal, Kathleen Dineen can make all arrangements: 773 702 1475. She can also help with the financial issues. I would see you myself. Regards, Fred Coe

              Reply
  4. Raquel D

    Thank you for the response, Dr. Coe. So it turns out I had the procedure yesterday. Urologist was able to remove seven of the 10 stones in my left kidney. THREE remain imbedded deep in the kidney tissue. Can I expect these will cause problems there? Thanks again.

    Reply
    • Fredric Coe, MD

      Hi Raquel, The imbedded stones are probably either plaque or tubule plugs. Your urologist knows which. IN neither case will the material itself migrate. But if plaque new stones may form in it; likewise if plugs. Your surgeon could not have removed these without damaging kidney tissue. Regards, Fred Coe

      Reply
  5. Raquel

    Hi,

    I was just hoping to post numbers from recent 24-urine test and see if Dr. Coe sees anything that jumps out. I am scheduled to have a ureteroscopy on Thurs. to remove about 10 stones from my left kidney – several of which are in the 9 mm range. I’ve had these for at least four years. Tried lithotripsy four years ago – which didn’t work well. (biggest stone wsa 5 mm back then). Then decided to leave it alone until discomfort in recent weeks. We don’t know what kind of stones other than likely calcium (according to my urologist because they show up on the xray.) Does anything look odd here? The doctors I’m seeing don’t see anything obvious. I notice my ss caOx is LOW and Creatine slightly high but that’s all I see that raise questions. Any help you can offer is appreciated.
    Component Results
    Component Your Value Standard Range
    VOLUME, URINE 2.17 L/day 0.50 – 4.00 L/day
    SS CAOX, URINE 2.40 6.00 – 10.00
    CALCIUM, URINE 77 mg/day 0 – 199 mg/day
    OXALATE, URINE 27 mg/day 20 – 40 mg/day
    CITRATE, URINE 941 mg/day >=551 mg/day
    SS CAPHOS, URINE 0.20 0.50 – 2.00
    PH, URINE 5.895 5.800 – 6.200
    SS URIC ACID, URINE 0.69 0.00 – 1.00
    URIC ACID, URINE 0.598 gm/day 0.000 – 0.749 gm/day
    CREATININE, URINE 1445 mg/day mg/day
    SODIUM URINE 115 mmol/day 50 – 150 mmol/day
    POTASSIUM, URINE 64 mmol/day 20 – 100 mmol/day
    MAGNESIUM, URINE 49 mg/day 30 – 120 mg/day
    PHOSPHORUS, URINE 0.724 gm/day 0.600 – 1.200 gm/day
    WEIGHT 54.4 kg kg
    CREATININE/KG 26.6 mg/kg 15.0 – 20.0 mg/kg
    CALCIUM/KG 1.4 mg/kg 0.0 – 3.9 mg/kg
    CALCIUM/CREATININE 53 mg/g 0 – 139 mg/g
    AMMONIUM, URINE 31 mmol/day 15 – 60 mmol/day
    CHLORIDE, URINE 129 mEq/day 70 – 250 mEq/day
    SULFATE, URINE 30 mEq/day 20 – 80 mEq/day
    UREA NITROGEN, URINE 7.65 gm/day 6.00 – 14.00 gm/day
    PCR 1.1 gm/kg/day 0.8 – 1.4 gm/kg/day
    CYSTINE SCREENING, URINE Negative Negative

    Reply
    • Fredric Coe, MD

      Hi Raquel, These numbers and your story are consistent. The stones slated for removal have been present for 4 years or more and your lab data are all normal with low stone risk. I suspect your stones formed in the past when your urine chemistries were quite different. I am not sure why surgery is now being done, but be sure all material removed is analysed to find out what you are forming – or have formed. Possibly much of what is seen is in the kidney tissue. Regards, Fred Coe

      Reply
  6. Nihal

    I have been diagnosed with a 7mm stone in my Right kidney (CT scan showed between renal pelvis and lowest calyx). I am weighing my options as to whether to do a ureteroscopy or SWL. I know SWL lithotripsy is less invasive but I am a little worried about the damage it might do to my kidney and or other organs, especially pancreas. I read some article which said there could be some long term damage to organs. I have type II diabetes and even the notes handed out to me by the Dr’s office about SWL said there could be 30-40% increase in the risk for diabetes. I certainly don’t want my diabetes to get worse and or have any long term damage to my kidneys, pancreas or any other organ as a result of SWL. Then there is the question of the efficacy of SWL due to the location of the stone and well as the fact that they can’t seem to spot the stone in a Xray. Due to the above reasons I am leaning towards ureteroscopy. Can you comment on the effects of SWL in terms of long term damage to organs (especially pancreas and kidney)?

    Reply
    • Fredric Coe, MD

      Hi Nihal, A single stones that size can be disrupted by SWL or removed via URS. From a single treatment little evidence supports important disease in the pancreas. Overall, URS may be preferable if the stone is hard to see. This is an area where the surgeon doing the work is the best authority. Regards, Fred Coe

      Reply
      • Nihal

        Dear Dr. Coe.

        Thank you for the response. Like the concept of ureteroscopy, but dreading the stent aspect of it.

        1. Are there techniques to better visualize stone during ESWL? I’ve heard terms like intravenous pyelogram. Can this be used during the ESWL to target the stone?

        2. I took a closer look at CT. in the coronal view I see one bright spot (~7x7mm , 450 average HU) and in the adjacent plane, very close to the first one another bright spot (4x4mm, 350 average HU). In the axial view, it is one long, thin bright spot (11×2.5mm, 330 average HU) . So I am guessing one stone, long and thin in the axial view and much wider in the coronal view. Based on the above, how small do you think the average stone fragment sizes be after ESWL? 1mm, 2mm, 3mm or bigger or even smaller?

        3. Location of the stone is another concern, CT scan shows it is between renal pelvis and lowest calyx (more biased towards the latter). I feel that the stone fragments after ESWL will fall into the lowest calyx. Would they come out on their own or would I have to do a subsequent ureteroscopy anyway to get these stone fragments out?

        Thank you very much for the great service your are providing

        Nihal

        Reply
        • Fredric Coe, MD

          Hi Nihal, You are asking me things I cannot answer as I would have to see the images themselves. Even so, your surgeon is the key person, and I would bring these issues directly to him/her. With ESWL fragments do often lodge in the lower pole. I like ureteroscopy more because a stone free kidney is the usual outcome, but once again your surgeon wants a stone free kidney for you and may well have reasons to choose the modality, reasons I cannot know from so far away. Regards, Fred Coe

          Reply
          • Nihal

            Dear Dr. Coe,

            Thanks for the response. Based on the average HU density of the stone – 450 HU for part of the stone and 350 HU for other part of the stone (see more details above), can you say whether this is very likely to be an Uric Acid stone or not?

            Thanks

            Nihal

            Reply
            • Fredric Coe, MD

              Hi Nihal, Low density like this is likely to be uric acid, but when very small stone density can become uncertain. The issue does matter. If uric acid it can dissolve and that would make surgery unnecessary. Have you done 24 hour urines? If so, is your average urine pH below 5.5? This latter is crucial for it not below 5.5 uric acid is most unlikely. Regards, Fred Coe

              Reply
              • Nihal

                Dear Dr. Coe,
                Thanks for the response. I haven’t done a 24 hr urine yet, but will get one done soon. Urine pH seems to be below 5.5 from the spot checks I am doing at home, plus I am a type 2 diabetic.

                Let me introduce a twist. What about if there is blood in the urine? I have had visible blood in the urine in the recent past, but lately the urine has a yellow tinge (in spite of all the water I am drinking), so I am pretty sure there is some blood in the urine. Would this skew the urine pH? Do I need to subtract the pH effect from the blood (I am not sure if there is even a way to do this), or is it the composite urine pH with blood that I need to worry about? I would assume that the stone formed before it started bleeding, so if we were looking for a root cause we would have to subtract that effect. The confusion arises if the composite pH value were to come above 5.5. If the composite pH came below 5.5, then I would think the pure urine pH would be below 5.5 as well.

                If I need to compensate for the blood effect, is there some extra parameter I need to request in the 24 hr urine test in order to do some calculation to subtract that effect?

                Thanks
                Nihal

              • Fredric Coe, MD

                Hi Nihal, diabetes will lower urine pH and famously causes uric acid stones. Blood has so little buffer capacity in the amounts present in urine you can ignore it totally. Just do the urine and see what is there. Regards, Fred Coe

              • Fredric Coe, MD

                Hi Nihal, diabetes will lower urine pH and famously causes uric acid stones. Blood has so little buffer capacity in the amounts present in urine you can ignore it totally. Just do the urine and see what is there. Regards, Fred Coe

  7. Sheffield Bailey

    Dear Dr. Coe.
    First, thank you for your making such a wealth of information available to kidney formers like myself. I passed several small stones 18 months ago that were determined to be primarily Calcium Phosphate. Recently I passed a Calcium Oxalate stone and had a number of other stones removed that are being analyzed as I write this note. A CAT scan shows a remaining stone in my left kidney (approximately 4mm) that I would like removed via the flexible uteroscopy technique. It is not yet available in my rural area. I can travel to San Francisco or Los Angeles area with equal ease. Can you recommend surgeons capable of providing a flexible ureteroscopy procedure to remove the remaining stone? I have joined Jill’s Facebook group and will enroll in her next stone formers education class. Many Thanks for all you have done, and are doing, to help. Regards, William Bailey email: swbailey3@gmail.com

    Reply
    • Fredric Coe, MD

      Hi Shelfield, UCSF has a superb surgeon, his name is Marshall Stoller. I would advise you call him. Feel free to say I personally recommended him to you – he is not only superb surgically he is a friend and colleague of mine in kidney stone research. Regards, Fred Coe

      Reply
  8. Maria M.

    Hello Doctor,
    I recently had a ureteroscopy performed for a supposed kidney stone. It turned out to be a pelvic phlebolith and they stopped the procedure. I am a young and healthy female, yet ever since the procedure I have experienced numbing pain on my clitoris and labia. Is is medically possible for a procedure such as this to cause nerve damage or lasting damage of any kind in those areas?
    I greatly appreciate the help!

    Reply
    • Fredric Coe, MD

      Hi Maria, I am afraid I am not a surgeon and not properly trained to answer your question. Possibly, being so close to where the scope enters you may be having some local and hopefully short lived symptoms. If they persist the first person to discuss this with is your surgeon who is most likely to be helpful. Regards, Fred Coe

      Reply
  9. Nick S

    Hello. Great article. I am working on a research report and it involves the number of ureteroscopy procedures performed every year. Do you have any idea how many ureteroscopy procedures are done every year in the USA? Are there other types of procedures (besides kidney stone removal) that either treat the ureter/kidney that is done minimally invasively through the urethra?

    Reply
    • Fredric Coe, MD

      Hi Nick, For that kind of detail, I would contact the primary author who is a urologist – Mike Borofsky. He is now at U Minnesota in Urology.

      Reply
      • Nick S

        Thank you! I’ve reached out to him directly via email.

        Reply
      • Nick S

        Dr Coe – Also, the project I am working on is with a large hospital in Miami. Please let me know if you would be interested in a summary on our idea and I can reach out to you directly via email.

        Reply
  10. Robert Hill

    Dr. Coe. On Friday the 21 October, the stone was broken using ESWL. Been passing lots of little teeny pieces since then. I have 3 ultra sound images, taken at various times during the process. In those, the dark spot in the cross hairs is there in image 1, smaller in image 2, and gone in image 3. This ESWL was done through my abdomen instead of the side. And it appears to have worked well. My sister, who took me to the place, said my doctor was only in the surgery room about 20 minutes. I’m kind of amazed it took so short a time to break that large of a stone.

    Still have a stent in place, and don’t understand how the pieces are getting out, since the urine flow is entirely through the stent? How could pieces midway in the ureter be getting out with a stent still in place?

    Reply
    • Fredric Coe, MD

      Hi Robert, I am glad it worked. Usually the fragments are small and pass though the lumen of the stent. Regards, Fred Coe

      Reply
      • Robert Hill

        Yes, I’m am getting many many teeny pieces that you need a magnifying glass to see. Yet there are enough of them to make a stone about half the size of the one that was in me, so far. Some are whitish, some black or reddish.

        Question: I know we have crystals in our urine. Could some of these pieces I am seeing be those crystals? Or are the crystals too small to see, even with a magnifying glass?

        If my doctor is looking out for me, he should want me to get some “after” CT scans? Because the images I’m seeing on the three ultra sound shots he gave me, are really not convincing to me. But then, I’m no expert on reading ultra sound images either. 😉

        Reply
        • Fredric Coe, MD

          Hi Robert, BE sure and get the material sent for stone analysis. Modern instruments will identify the crystals easily and that is crucial for ongoing prevention. An after low radiation CT is a good approach, and invaluable for monitoring prevention. Regards, Fred Coe

          Reply
          • Robert Hill

            Stent was removed today after 8 weeks of having one in me. Hurt like hell when he pulled the strings and took it out. Anyhow, I’m experiencing some side pain, nothing too terrible, but I don’t want to feel this for two more days. Also passing larger stone fragments now that the stent is out of the way. I’m confident from that, the stone is gone and my right kidney must be functioning normally.

            Reply
  11. Robert Hill

    Well, went in for a second ureteroscopy yesterday. Once again, my doctor was unable to gain access to the stone with a laser to break it up. This is really hard on me. He is going to try ultrasonic lithotripsy through my belly, since he will not be able to get it from the side. Says it’s been done before, and is hit or miss if it will work.

    Told me my options if he cannot get it out, are pretty limited. I could just forget about it, let the kidney die, and go on with my life, it would cause no risk. Told me they could surgically remove the part of my ureter that the stone resides in, but it is a very tricky surgery repairing such a small internal organ such as a ureter. And told me the best option is to remove the kidney and go on with life.

    I’m torn. My left kidney has never had a stone, always my right. But, my urine has the ingredients for stones, obviously. So, remove my right kidney, the stone problem goes to my left kidney, and I have no further backup. Scary. The stone plugging my right kidney gave no really bad indications it was this bad. Thought it was just another stone that would pass. Ended up with Severe Hydronophrosis, and a really damaged kidney. It has, because of the stent, returned to normal size. And I believe, due to the urine color after the stent was installed, I believe it is functioning normally.

    I really hate to lose my kidney because my doctor is unable to get the stone out. I’ll give the Ultrasound a try, I’ve no other choice.

    Doctor Coe, will this work?

    Reply
    • Fredric Coe, MD

      Hi Robert, Given that stones fill form on both sides I would not readily accept loss of a kidney and would immediately seek another urological expert. Perhaps your urologist might know about possibilities in your part of the world. I do not know where you live of if you can travel, but perhaps you might want to email me directly – this kinds of matters are perhaps no longer ideal in a public space. Regards, Fred Coe

      Reply
      • Robert Hill

        My doctor has been doing this for many years. He came highly recommended. He said something about scar tissue from previous stone passage blocking his ability to get the laser on the stone. It is an almost 3/8 inch stone, and one has to wonder how that cannot be found.

        I cannot find your email address on the site. I would gladly do that.

        I’m in Midwest City Oklahoma, just east of Oklahoma City.

        Reply
        • Fredric Coe, MD

          Obviously your personal physician is excellent and I am too far from the situation to say anything more than the most general of statements. Regards, Fred Coe

          Reply
          • Robert Hill

            The Doctor you recommended called me last night, we spoke for about 10 minutes. He is going to try and obtain my CT scans and medical records from my physician here. I also have the CT scans available on two CD’s, one dated August 15 2016 and the other September 27 2016.

            Reply
            • Fredric Coe, MD

              Hi, THanks for writing. I know as he copied me on his email. Good luck with the kidney. I hope you can keep it in good shape. Regards, Fred Coe

              Reply
    • Michael Borofsky M.D.

      Dear Robert,

      It sounds like you are in a challenging situation. Situations such as the one you describe are quite complex and while I am unable to definitively comment on your current treatment without your medical records I would certainly not jump to have your kidney removed unless this is an absolute last option. Whereas removing kidneys for stones was once common, modern techniques both in stone removal and urinary reconstruction have made the need for this very rare anymore. I would strongly advise you to seek a variety of opinions from regional experts, specifically those at an academic teaching hospital or with subspecialty training in endourology prior to considering this approach.

      Sincerely,
      Mike Borofsky

      Reply
      • Robert Hill

        Doctor Coe has provided me with the email address of a Dr. Lingeman. I have sent him a pretty detailed email of my situation as it currently stands. Yes, I do not want to lose my kidney, not being the stonemaker I am. So, currently I am awaiting a reply from Dr. Lingeman. I’ll see what transpires after that.

        Anyhow, my doctor is Stanford Law. His practice is in Midwest City Oklahoma. He has many CT scans of my kidneys, dating back to July 2015.

        http://www.alliancehealthmidwest.com/physician/361186/G.%20Stanford+Law

        Thank you for your reply. I appreciate it greatly.

        Reply
  12. Robert Hill

    I underwent ureteroscopy for the first time September 8 2016. This after having done ultrasonic lithotripsy in August 2015. I have a 9mm stone plugging my right ureter, and severe hydronophrosis. The doc was unable to get to the stone the first time, and he put a stent in to allow my kidney to drain for three weeks. Going in for a second time on Sept. 29th. Not looking forward to it at all, the pain afterwards when you wake and need to pee is intense, to say the least. Feels like you’re peeing razor blades. Sucks. Hate having to do it a second time, dreading it to the NTH degree. And the stent has caused me to practically live in the bathroom the last three weeks, pissing my insides out. Occasionally, it still hurts, even after almost three weeks, and I still get bloody urine after almost three weeks. I hate this!

    I have a vial with a bunch of stones I passed in 2015, most are dark in color. Showed them to my urologist, and was surprised he did not want to take them from me to have them analyzed. You would think he would want to do that, so I can figure out what strategies to use to stop them in the future. Been making stones since 2001, when I had my first occurrence. Had none again until 2009, but had no insurance and had to live with them. When he gets this large one out of my ureter, I certainly hope he tries to determine what kind of stone it is. After the ultrasonic lithotripsy in 2015, wouldn’t they have had the ability to get some samples of the fragments since they had a catheter inside me throughout the procedure?

    I’m reaching the end of my rope here. At 55 years of age, I do not want to have to have this procedure done on me again, it’s a horrible experience. If I have to look forward to stone removal every year or so, I may not desire to go on for much longer. It’s painful, even after three weeks. Disrupts your life for the entire time the stent is in place. Looking at six weeks now, since he will probably stick another damn stent in me after the procedure on the 29th. And what if he still cannot get the stone the second time? I’m frightened even contemplating that!

    Reply
    • Fredric Coe, MD

      Hi Robert, You are right. Analysis of the stones is crucial as is an organized approach to stone prevention. I would have your personal physician get them analysed and help you through the steps in the link or refer you to someone who can. Urologists are busy surgeons and often do not have enough time to deal with the prevention problems. Given the numbers of stones and procedures you do need to insist on proper prevention efforts and stone analysis is essential. Regards, Fred Coe

      Reply
  13. Jim

    I had ureteroscopy done twice in a 4-week span and I am deeply regretting it. The first procedure was aborted when the doctor perforated my ureter…oops! butterfingers! The second procedure just shattered the stone and left me passing out huge chunks and in pain. The only way to be absolutely sure the whole stone is removed is to do the actual percutaneous surgery.

    Reply
    • Michael Borofsky M.D.

      Dear Jim,

      I am sorry to hear that your recent surgical experience did not go as planned. You are correct that in general a percutaneous approach does have a higher success rate in complete removal of large and complex stones; however, this approach is typically more complex as well and does carry with it higher potential for bleeding and other complications. As our experience with ureteroscopy evolves, both in technology and technique, we are hopeful that we may one day be able to achieve complete stone removal each time in the most minimally invasive of fashions. For the time being however, a unique strategy must be determined for each patient and each stone to balance the risks and benefits of each approach we have to offer (shock wave lithotripsy, ureteroscopy, and percutaneous nephrolithomy). Choosing the best approach depends on several factors including overall health, the size, shape and location of the stone, and the comfort level of the surgeon performing each technique. Perhaps this would be a good topic to discuss in a future article.

      Hopefully you are through the worst. Make sure you save a piece of stone for analysis if one has not already been performed and please wander through the rest of the website to learn how to best prevent a new stone from forming in the future.

      Sincerely,
      Mike Borofsky

      Reply
  14. M. McNeil

    A recent CT shows two “tiny” fragments remain from a recent dusting I the right kidney. And a 3 x 9 mm stone in the left which has moved since the CT done three months ago and is causing hydronephrosis. I am very concerned about the remaining fragments and what can be done to prevent another such painful procedure.
    But I also concerned about the shock wave lithotripsy scheduled in ten days. I have a lap band in place. I have asked if this is a problem and the answer is no. But considering the shock wave technique and the lap band position is there a reliable answer? Is damage a real possibility?

    Reply
    • Fredric Coe, MD

      Hi M, Dusting has the virtue of no sheath, but remnants are not rare. Perhaps URS could be an alternative for the left stone if you are concerned about SWl, but I know of no instances in which SWL has interacted badly with banding. To be sure, perhaps you should speak with the surgeon who did your banding, as that person should know if SWL is a risk. As for the fragments, very often they are small enough to pass, and will. Several of the trials have shown that potassium citrate can reduce fragment growth. Regards, Fred Coe

      Reply
  15. Trish McClain

    This is a very informative article and explains what sick people really need to know. I might add, Dr. Portis has a
    You Tube video showing a utererscopy
    I know he is one of the top endourologists in the US and is respected by his colleagues.

    Trish

    Reply
  16. Emil Donofrio

    I found your site very helpful. I just had a ureteroscopythis afternoon and am very interested in follow up care. With so much conflicting information on the Internet these days, I feel that your site contains solid, objective information which helps kidney stone sufferers learn more about their condition

    Reply

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