Can a CT scan detect the cause of my pelvic‑floor pain and loss of bladder‑filling sensation after a fistulotomy?

CT Scan for Post-Fistulotomy Pelvic Floor Pain and Bladder Sensation Loss

CT scan has very limited utility for evaluating pelvic floor pain and loss of bladder sensation after fistulotomy, as it cannot adequately visualize the soft tissue structures, nerves, and muscles responsible for these symptoms.

Why CT Is Not the Appropriate Imaging Modality

Poor Soft Tissue Resolution

• CT has inherently poor soft-tissue resolution that makes visualization of pelvic floor musculofascial structures extremely challenging 1
• The synthetic materials and native tissue changes along the anterior and posterior vaginal walls are not depicted well on CT 1
• CT cannot directly depict pelvic floor musculofascial structures that are critical for understanding voiding dysfunction 1

Lack of Evidence for Post-Surgical Complications

• There is no relevant literature supporting the use of CT for routine assessment or initial imaging of patients with subacute or chronic complications of pelvic floor surgery 1
• While CT may be used for acute post-operative complications, it is not indicated for the chronic symptoms you describe 1

Cannot Evaluate Functional Complications

• Your symptoms (pelvic floor pain and loss of bladder-filling sensation) suggest functional complications from devascularization and denervation, which CT cannot assess 1
• CT provides no functional assessment capability for voiding dysfunction 1

What CT Can Show (Limited Scenarios)

CT has minimal utility but can demonstrate:

• Calcified urethral bulking agents (if present) 1
• Bone anchors or retropubic arms of urethral slings (not applicable to fistulotomy) 1
• Acute complications like abscess or hematoma (but your symptoms are chronic) 1

Recommended Imaging Algorithm for Your Symptoms

First-Line: MRI Pelvis

MRI is the imaging modality of choice for evaluating post-surgical pelvic floor complications with pain and voiding dysfunction 1

• MRI provides superior soft-tissue contrast resolution for anatomic evaluation of pelvic organs and structural changes after surgery 1
• MRI accurately depicts pelvic floor muscular anatomy, integrity, and function 1
• MRI is particularly useful for assessing muscular hypertonicity in chronic pelvic pain syndromes, which may explain your symptoms 1
• MRI can visualize nerve injury, scarring, and devascularization that cause persistent pain and voiding dysfunction 1
• Gadolinium IV contrast enhances detection of complications such as fistulas or collections 1

Second-Line: Voiding Cystourethrography (VCUG)

• VCUG can assess for urinary dysfunction in the post-operative setting 1
• It may show indirect findings of voiding dysfunction such as trabeculated bladder and large post-void residual 1
• However, VCUG cannot directly depict the pelvic floor structures causing your symptoms 1

Complementary: Pelvic Floor Physical Therapy Evaluation

• Clinical assessment by a specialized pelvic floor physical therapist can identify pelvic floor spasm (hypertonicity), which commonly causes voiding dysfunction and pain 2
• This condition often requires video urodynamics and/or electromyography for definitive diagnosis 2

Critical Pitfalls to Avoid

• Do not pursue CT imaging for chronic pelvic floor pain and voiding dysfunction after pelvic surgery – it will not provide diagnostic information and exposes you to unnecessary radiation 1
• Do not assume imaging alone will diagnose the problem – functional disorders like pelvic floor spasm may not show structural abnormalities on any imaging 3, 2
• Ensure MRI is performed with gadolinium contrast for optimal evaluation of post-surgical complications 1

Clinical Context

Your symptoms of pelvic floor pain and loss of bladder-filling sensation after fistulotomy suggest:

• Possible nerve injury (pudendal or pelvic nerve damage) 1
• Pelvic floor muscle spasm or hypertonicity 1, 2
• Excessive scarring causing functional impairment 1
• Devascularization leading to chronic pain and voiding dysfunction 1

None of these conditions are adequately evaluated by CT scan 1.