Safety and Effectiveness of Ureteral DJ Stent With Magnet (Blackstar, Urotech) Removal Under Ultrasound Control
Condition: Urolithiasis
MeSH terms: Urolithiasis
Study type: Interventional

Summary: 
      Evaluation of safety and effectiveness of ureteral DJ stent with magnet (Blackstar, Urotech),
      severity of stent-association symptoms and pain level syndrome after stent extraction
      compared with stent extraction by flexible cystoscope
    

Detailed description: 
      Inclusion Criteria:

        -  age from 18 to 70 years

        -  males

        -  Indications for rigid or flexible URS

        -  ASA score: 1-3

      Exclusion Criteria:

        -  Active urinary tract infection

        -  taking alpha-1 adreno and M-cholinoblockers

      All patients will be randomized into 2 groups:

        -  group A - male patients who will undergo ureteral stent placement by conventional
           polyurethane DJ stent, Fr 6.5. N=30

        -  group B - male patients who will undergo ureteral stent placement by polyurethane DJ
           stent with magnet (Blackstar, Urotech ), Fr 7. N=30 Patients are to be assigned a
           randomization number that will match their treatment. Block randomization using 10
           blocks is to be performed by a central randomization organization (www.randomize.net)
           using a computerized algorithm.

      Using the Visual Analog Scale of Pain (VASP) and Ureteric Stent Symptom Questionnaire (USSQ)
      we are going to assess the pain syndrome and the severity of stent-associated symptoms. The
      USSQ will be filled twice: 3 days after stent placement and on the day of stent removal, just
      before the procedure. All stents will be removed 30 days after placement. Also, immediately
      after stent removal, patients will complete the VASP questionnaire. In the control group, the
      stent will be removed using flexible cystoscopy. In the experimental group under ultrasound
      control using a magnetic retriever, with a bladder capacity of at least 150 ml.

      Primary assessed outcomes:

        1. Age

        2. Body mass index

        3. Operation side

        4. The density of the stone

        5. Type of the operation

        6. Applying of the ureteral accessing sheath

        7. Type of the ureteral stent

        8. Troubles with stent placement

        9. USSQ (Ureteral stent symptom questionnaire) 3 days after surgery

       10. USSQ before stent extraction

       11. VASP (Visual Analog Scale Pain) immediately after stent extraction

       12. Duration of stent extractiom by magnetic retrieval device

       13. Duration of stent extraction by cystoscopy

       14. Stent removal success (yes/no)

      Secondary assessed outcomes:

        1. Assessment of Stone-free status after surgery by performing computed tomography of
           kidneys and urinary tract without intravenous contrasting 1 month after surgery

        2. Stent encrustation
    

Intervention name(s): stent extraction
Intervention type(s): Device
Intervention description(s): stent extraction using magnetic retriever or flexible cystoscope
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: group A - male patients who will undergo ureteral stent placement by conventional polyurethane DJ stent, Fr 6.5. N=30
group B - male patients who will undergo ureteral stent placement by polyurethane DJ stent with magnet (Blackstar, Urotech ), Fr 7. N=30
Masking: Single (Investigator)
Primary purpose: Treatment