When should an adult with autosomal dominant polycystic kidney disease be screened for intracranial saccular (berry) aneurysms, which imaging modality is preferred, and how should detected aneurysms be managed?

Screening and Management of Intracranial Aneurysms in ADPKD

Adults with ADPKD should be screened for intracranial aneurysms if they have a personal history of subarachnoid hemorrhage OR a family history of intracranial aneurysm, subarachnoid hemorrhage, or unexplained sudden death, using time-of-flight MRA without contrast as the preferred imaging modality. 1

Who Should Be Screened

Definite Indications for Screening

• Personal history of subarachnoid hemorrhage - These patients require screening regardless of other factors 1
• Positive family history of intracranial aneurysm, subarachnoid hemorrhage, or unexplained sudden death in first-degree relatives 1
  • Risk increases from 10-11.5% in ADPKD patients without family history to 16-23% with positive family history 1

Additional Screening Considerations

• Pre-transplant evaluation - Screening should be discussed before kidney or liver transplantation 1
• Before major elective surgery - Consider screening in this clinical context 1
• Women planning pregnancy - If screening is indicated for other reasons, perform before conception 1
• Patient preference - After comprehensive education about risks and benefits, patients who prefer screening should have access to it 1

Who Should NOT Be Screened

• Children with ADPKD - Screening is not recommended as aneurysm rupture is exceedingly rare in childhood 1
• Patients without reasonable life expectancy or who would not be eligible for treatment 1

Preferred Imaging Modality

First-Line: Time-of-Flight MRA Without Contrast

• Time-of-flight MRA without gadolinium enhancement is the recommended screening method 1, 2
• Sensitivity of 86% and specificity of 84% for detecting aneurysms 1
• Noninvasive with no radiation exposure or contrast requirements 1

Alternative: High-Resolution CT Angiography

• CTA can be used as an alternative when MRA is contraindicated or unavailable 1, 2
• Sensitivity >90% for aneurysm detection 1
• Important limitation: Sensitivity decreases significantly for aneurysms <3mm and those adjacent to bone 1

NOT Recommended for Screening

• Catheter angiography - The invasive nature and procedural risks are not justified for screening 1

Rescreening Intervals

• If initial screening is negative in high-risk patients: Individualized rescreening every 5-10 years based on risk factors, age, and life expectancy 1
• If aneurysm detected: Follow surveillance protocols determined by multidisciplinary team 1

Management of Detected Aneurysms

Multidisciplinary Evaluation Required

• All detected aneurysms require assessment at high-volume centers of expertise with multidisciplinary teams including neurosurgery and interventional neuroradiology 1
• Treatment options include:
  • Conservative management with surveillance
  • Microvascular (surgical) repair
  • Endovascular repair 1

Key Management Principles

• Most aneurysms detected by screening are small (median 3.5mm) and located in anterior circulation (77-84%) 3, 4
• Growth and rupture risk in ADPKD patients is NOT higher than general population with similar-sized aneurysms 3, 4
• During 243 years of cumulative follow-up in one study, no screened aneurysms ruptured 3
• Poor outcomes occur almost exclusively with ruptured presentation, not elective treatment 5

Critical Risk Factor Modification

Mandatory Interventions

• Smoking cessation is essential - Smoking is the strongest modifiable risk factor for aneurysm development and rupture 1, 2

  • Provide behavioral interventions and pharmacotherapy for cessation 1

• Aggressive blood pressure control - Uncontrolled hypertension significantly increases risk of aneurysm formation and rupture 1, 2

  • Diagnose and treat hypertension early and adequately 1

Patient Education Requirements

Symptoms Requiring Immediate Medical Attention

• Thunderclap headache - Sudden onset severe headache reaching maximum intensity within seconds to one minute 1, 2
• This is the hallmark symptom of aneurysmal rupture requiring emergency evaluation 1

Counseling Points

• Inform all ADPKD patients about increased aneurysm risk even if not screened 1
• Discuss implications of positive screening (e.g., life insurance eligibility, anxiety) 1
• Explain that most detected aneurysms are small and do not rupture 3, 4

Common Pitfalls to Avoid

• Do not screen universally - Despite some cost-effectiveness data 6, current guidelines recommend selective screening based on risk factors 1
• Do not use catheter angiography for screening - Procedural risks outweigh benefits 1
• Do not assume ADPKD aneurysms have higher rupture risk - Evidence shows similar rupture rates to general population for comparable aneurysms 1, 3, 4
• Do not neglect risk factor modification - Even without screening, all ADPKD patients need smoking cessation and blood pressure control 1

Controversial Areas

While the 2025 KDIGO guidelines recommend selective screening 1, one cost-effectiveness study suggested universal screening may be justified given that 64% of ADPKD patients presenting with subarachnoid hemorrhage had no prior family history 5, 6. However, the most recent and authoritative KDIGO 2025 guidelines support selective screening, which should guide clinical practice 1.