Sonographic Examination of Renal Function in Individuals With Long-term Spinal Cord Injury

Study Overview
=================
Brief Summary
-----------------
Patients with long-term lower urinary tract dysfunction due to spinal cord injury presenting for a routine urodynamic control will be screened for inclusion and exclusion criteria. Suitable individuals providing written informed consent will undergo renal Doppler sonography and renal scintigraphy in addition to the routine examinations. Conclusions regarding renal function based on the clearance rate determined by scintigraphy (gold standard) will be compared with the conclusions based on Doppler sonography and Cystatin C clearance.

Official Title
-----------------
Comparison of Sonographic Examination of Renal Function With Gold-standard Examination in Individuals With Long-term Spinal Cord Injury

Conditions
-----------------
Spinal Cord Injuries, Renal Insufficiency

Intervention / Treatment
-----------------
* Diagnostic Test: renal scintigraphy
* Diagnostic Test: renal doppler sonography


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: long-term spinal cord injury (≥10 years) age ≥30 years written informed consent Exclusion Criteria: dementia or severe intellectual impairment serious internal illness previous or current tumor disease known allergy to the radioactive marker (Technetium) pregnancy or breastfeeding withdrawal of informed consent

Ages Eligible for Study
-----------------
Minimum Age: 30 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| normal renal function<br>individuals with renal clearance >89 ml/min/1.73m² | Diagnostic Test: renal scintigraphy<br>* Technetium-99m-dimercaptosuccinic acid scintigraphy of both kidneys<br>Diagnostic Test: renal doppler sonography<br>* doppler ultrasound of both kidneys<br>|
| mild renal insufficiency<br>individuals with renal clearance 60-89 ml/min/1.73m² | Diagnostic Test: renal scintigraphy<br>* Technetium-99m-dimercaptosuccinic acid scintigraphy of both kidneys<br>Diagnostic Test: renal doppler sonography<br>* doppler ultrasound of both kidneys<br>|
| moderate renal insufficiency<br>individuals with renal clearance 30-59 ml/min/1.73m² | Diagnostic Test: renal scintigraphy<br>* Technetium-99m-dimercaptosuccinic acid scintigraphy of both kidneys<br>Diagnostic Test: renal doppler sonography<br>* doppler ultrasound of both kidneys<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| renal clearance | renal clearance of Technetium-99m-dimercaptosuccinic acid determined by scintigraphy | at the time of inclusion into study | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cystatin C concentration | blood serum concentration of Cystatin C (mg/L) | at the time of inclusion into study | 
| Cystatin C clearance | renal clearance of Cystatin C (ml/min) according to the Grubb formula | at the time of inclusion into study | 
| renal peak systolic velocity | Doppler sonography evaluation of renal blood flow during systolic heart phase (m/s) | at the time of inclusion into study | 
| renal peak enddiastolic velocity | Doppler sonography evaluation of renal blood flow during enddiastolic heart phase (m/s) | at the time of inclusion into study | 
| renal resistive index | (systolic velocity - enddiastolic velocity) / systolic velocity | at the time of inclusion into study |