Epidural Patching For Lateral Dural Tears In Spontaneous Intracranial Hypotension

1. Patient Selection Confirmed or highly suspected lateral dural tear causing SIH

Imaging evidence of spinal longitudinal extradural CSF collection (SLEC)

Symptoms consistent with SIH: orthostatic headache, nausea, cognitive fog

Conservative management (hydration, caffeine) has failed

2. Preprocedural Imaging High-resolution spine MRI and/or dynamic CT myelography to localize the leak

Identify:

Exact spinal level

Laterality

Presence of herniated arachnoid pouch (important for prognosis)

3. Patient Positioning Prone position on CT table

Local anesthesia with sterile prep

Vital signs monitored throughout

4. CT-Guided Needle Placement Transforaminal or interlaminar approach, depending on location

Under real-time CT guidance, a spinal needle is advanced into the epidural space

For lateral tears, targeting the paraspinal portion of the epidural space adjacent to the leak

5. Injection of Patch Material Commonly used materials:

Autologous blood (standard)

Fibrin glue, dextran, or mixed agents in some centers

Volume varies, but typically 5–15 mL depending on patient size and tolerance

Some protocols aim for needle positioning adjacent to or into the herniated arachnoid pouch, though this did not affect outcomes in the study

6. Postprocedural Care Patient remains supine or in mild Trendelenburg for 1–2 hours

Monitor for:

Resolution of orthostatic symptoms

Neurologic complications (rare)

MRI follow-up in weeks to months to assess SLEC resolution

7. Considerations Presence of a herniated arachnoid pouch may predict lower success rate

Clinical improvement may occur despite persistent imaging abnormalities

Repatching or surgical repair may be required in refractory cases

In a multicenter retrospective cohort study, Callen et al. — from the University of Colorado Anschutz, Kaiser Permanente Santa Clara, University of Freiburg, Cambridge University Hospitals, Newcastle upon Tyne Hospitals, Guy’s & St Thomas’s / King’s College Hospitals, and King’s College London — published in the American Journal of Neuroradiology, evaluated the clinical and radiologic outcomes of CT-guided epidural patching in patients with lateral dural tear causing spontaneous intracranial hypotension (SIH). The study also aimed to determine whether anatomic factors (e.g., herniated arachnoid pouch) or procedural variables (e.g., patch volume, material, approach) predict treatment success.

CT-guided patching led to complete symptom resolution in approximately one-third of patients. The presence of a herniated arachnoid pouch was associated with lower radiologic resolution of CSF collections. Procedural variables — such as patch type, approach, and volume — were not associated with outcomes. Notably, some patients experienced clinical improvement despite persistent CSF collections, highlighting the need for long-term follow-up and cautious reliance on imaging alone.

¹⁾

CT-guided epidural patching for lateral dural tears in spontaneous intracranial hypotension offers limited success — with complete symptom resolution in only one-third of patients.

The presence of a herniated arachnoid pouch significantly reduces the likelihood of radiologic improvement, and procedural variables (volume, approach, material) do not reliably predict outcomes.

Clinical recovery does not always correlate with radiologic resolution, emphasizing the need for long-term follow-up and careful clinical judgment over imaging alone.

In refractory cases or those with anatomical barriers to patch efficacy, surgical exploration may be warranted.

📉 The Results (And the Letdown) Clinical resolution: 35.7% (i.e., two-thirds of patients did not improve)

Radiologic resolution (SLEC): 25%

No procedural variable — neither patch volume, approach, nor material — predicted success

Patients with herniated arachnoid pouches did worse — an unmodifiable anatomical detail

🧱 Cracks in the Foundation

1. Retrospective ≠ Evidence No control group, no randomization, no standardization across 8+ centers

Heterogeneous protocols lumped together as if they represented a coherent treatment pathway

2. Sample Size Embarrassment Only 56 patients in 12 years across major international centers?

That’s not a cohort, it’s a collection of anecdotes

3. Outcome Disconnect Nearly half of patients with clinical improvement had persistent CSF collections on MRI

Radiologic endpoints are decoupled from clinical status, yet form the basis for conclusions

Either the patch doesn’t work as intended — or the wrong metrics are being used to judge it

4. Anatomic Fatalism The only predictive factor (herniated arachnoid pouch) is not actionable

So the implicit message is: “Patch everyone, cross your fingers”

5. Unaddressed Variables

No stratification by patching experience, time from symptom onset, or leak size

No mention of functional outcomes, recurrence rates, or durability

No comparison with surgical repair or repeat patching outcomes

🧠 What Should a Neurosurgeon Do with This?

Probably not patch — at least not without a backup plan.

This paper offers no practical algorithm, no reliable predictors, and no improvement over the status quo. It reinforces what most already suspected: epidural patching in lateral dural tears is an unreliable fix for a structurally problematic leak.

In fact, this study might better serve as evidence against CT-guided patching in this subgroup — or, at minimum, a call to abandon radiologic resolution as a therapeutic endpoint.

🚫 Final Verdict This is not a breakthrough. It’s a long, methodologically diluted, and clinically unhelpful retrospective that confirms what was already known: Patching lateral dural tears is hit-or-miss — mostly miss.

Better to operate, than to hope.