Introduction
Neurogenic bladder develops when the nerves and the urinary bladder do not work well together, causing medical issues like the frequent urgency to urinate often or accidents. If the patient suffers from this medical issue, the healthcare professional might suggest some radiological tests to diagnose this condition. X-rays and ultrasounds are usually used to detect the problem radiologically. These imaging tests help examine the urinary bladder, spine, and brain. However, these are only some of the tests that are needed. There are other tests, but these tests also give crucial information to help identify the condition.
Several articles have discussed the symptoms and causes of neurogenic bladder, but the related radiographic findings are not usually presented. Some of the common causes of neurogenic bladder include spinal cord injuries due to trauma, birth defects like spina bifida (a defect wherein the spinal cord of a developing baby fails to develop properly), multiple sclerosis (the immune system causes damage to the protective covering of the nerves), syphilis, diabetes, and malignant tumors. Clinical symptoms might vary depending on the severity and the extent of the damage caused. Some individuals might develop trouble emptying their urinary bladder fully. This may lead to an embarrassing situation, causing leakage. Other patients might lose their control over their bladder. This may lead to constant dribbling of urine or unexpected peeing.
The radiographic findings in the neurogenic bladder are often due to the direct effect of neuromuscular problems on the urinary bladder and sphincters and the indirect effects of resulting urinary obstructions. Additionally, secondary infections and the formation of urinary bladder stones can impact X-ray images. This article focuses on the radiographic findings in the neurogenic bladder to help the clinician identify the medical issue promptly and find an apt solution.
What Is a Neurogenic Bladder Dysfunction?
Neurogenic bladder refers to a medical condition where normal bladder function is disrupted and impaired due to nerve damage or other nervous system disorders. In the neurogenic bladder, the nerves that send messages between the urinary bladder, spinal cord, and brain do not function properly. Some of the common symptoms of neurogenic bladder dysfunction include:
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Urine leakage.
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Inability to feel when the bladder is full.
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Inability to control urination (urinary incontinence).
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Dribbling of urine.
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Pain and burning sensation due to urinary tract infection.
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Urinary retention.
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Increased urinary frequency.
What Are the Common Radiographic Findings Associated With Neurogenic Bladder?
Some of the common radiographic findings that are associated with neurogenic bladder include:
1. Changes in the Urinary Bladder Shape and Size:
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Bladder Trabeculation: The bladder wall is thickened due to chronic overactivity of the bladder muscles or urethral obstruction. The urethra is the tube that drains the urine from the urinary bladder.
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Bladder Diverticulum: A defect in the detrusor muscle fibers may cause herniation of the bladder muscles. In simple words, bladder wall outpouchings occur due to increased pressure or weakened bladder walls.
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Capacity and Compliance: Compliance refers to the change in the urinary bladder volume for each unit change in detrusor pressure (measured in mL/cm H2O). Changes in bladder size may be either small and spastic or large and atonic. These can be detected on the radiograph. The urinary bladder can hold up to 500 ml (0.132 gallons) of urine in women and 700 ml 90.184 gallons) in men. Changes in the bladder capacity may also be observed in the radiographic findings.
2. Changes in the Upper Urinary Tract:
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Hydronephrosis: It is a condition characterized by the buildup of excess fluid in a kidney due to urine backup. This may lead to kidney swelling and stretching due to urine outflow obstruction.
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Hydroureter: The ureter may become bigger than normal. Dilation of the ureter is often seen alongside hydronephrosis. There is an abnormal dilation of usually more than three millimeters (3 mm).
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Vesicoureteral Reflux (VUR): Vesicoureteral reflux (VUR) is a condition with a backward urine flow from the urinary bladder into one or both ureters. The urine may sometimes reach the kidneys. Vesicoureteral reflux (VUR) is accurately diagnosed using fluoroscopic voiding cystourethrography (VCUG). VCUG helps determine the presence and severity of the reflux and helps provide a detailed view of the bladder shape, bladder neck, and the anatomical dissection of the ureters and urethra.
3. Alterations in the Bladder Function and Filling Defects:
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Post-Void Residual (PVR) Urine Test: The post-void residual (PVR) test measures the amount of urine in the bladder after the patient's urination. High PVR levels indicate high urinary retention and incomplete bladder emptying.
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Filling Defects: They are tumors, stones, or clots that can be detected in radiological imaging studies during the bladder filling phases.
4. Specific Radiographic Signs:
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Christmas Tree Bladder: It is usually seen on VCUG and suggests severe trabeculation. A "Christmas tree bladder," or the "pine cone bladder," is a cystography appearance usually seen in severe neurogenic bladder cases with increased sphincter tone. This appearance is, however, not specific to the neurogenic bladder. It can also occur with bladder-neck obstruction from non-neurogenic causes.
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Cobra Head Sign: Also known as the spring onion sign. It refers to the dilatation of the distal end of the ureter. This sign indicates ureterocele on intravenous pyelogram (IVP).
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Fishhooking of the Ureter: It may occur due to benign prostatic hyperplasia. It develops due to kinking or high insertion of the ureter. It may occur secondary to chronic obstruction.
What Are the Radiological Imaging Modalities Used For Neurogenic Bladder?
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Ultrasonography: Ultrasound is a noninvasive imaging technique used to assess bladder wall thickness, the amount of residual urine, and any dilatation present in the upper urinary tract.
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X-ray and Fluoroscopy (Voiding Cystourethrography, VCUG): These imaging techniques visualize the urinary bladder and urethra during filling and voiding. VCUG is helpful for detecting VUR, anomalies, and defects in the bladder shape and bladder diverticulum.
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CT (Computed Tomography) and MRI (Magnetic Resonance Imaging): These radiographic techniques help provide detailed anatomical information about the neurogenic bladder. They are also useful for identifying complex cases or associated abnormalities.
What Is the Interpretation of the Radiographic Findings and Management of the Neurogenic Bladder?
To effectively manage the neurogenic bladder, the interpretation of the radiographic findings must be in conjunction with clinical symptoms and urodynamic studies. Therapeutic management often includes pharmacological treatment, intermittent catheterization, or surgical interventions to correct complications such as VUR or severe bladder trabeculation.
Conclusion
A neurogenic bladder is usually referred to as a dysfunctional urinary bladder. Radiographic imaging provides crucial insights into the structural and functional abnormalities in patients with neurogenic bladder. These findings help customize individualized treatment plans to prevent complications and improve patient health outcomes.
