Pott’s puffy tumor (PPT) is a rare but clinically significant complication of frontal sinusitis, characterized by frontal bone osteomyelitis and a subperiosteal abscess.^{Reference Koltsidopoulos, Papageorgiou and Skoulakis1,Reference Sideris, Davoutis, Panagoulis, Maragkoudakis, Nikolopoulos and Delides2} Although venous sinus involvement is an important driver of adverse outcomes, distinguishing true cerebral venous sinus thrombosis (CVST) from extrinsic venous sinus compression can be challenging on first-line imaging. The management ramifications are substantial: premature anticoagulation may complicate urgent surgery without improving outcomes if the venous pathology is purely compressive.^{Reference Salomão, Cervante and Bellas3,Reference Ketenci, Unlü, Tucer and Vural4}

We present a previously healthy 14-year-old boy with progressive forehead swelling and headache following an upper respiratory infection. Initial non-contrast CT was non-diagnostic. Subsequent contrast-enhanced imaging identified frontal osteomyelitis with midline extension and an adjacent epidural collection. Magnetic resonance venography (MRV) demonstrated loss of flow signal in the anterior superior sagittal sinus (SSS), interpreted as possible acute CVST (Figure 1).

Figure 1.

Contrast-enhanced MRI (A), MRV (B) and CT (C) examinations, respectively. MRV, magnetic resonance venography.

Given the clinical trajectory and proximity of the collection to the SSS, urgent surgery was undertaken. A bicoronal approach allowed drainage of subgaleal and epidural pus (Figure 2A). A limited frontal craniotomy facilitated debridement of infected bone and sinus mucosa. On raising the bone flap, a visible impression over the SSS suggested direct extrinsic compression (Figure 2B). Broad-spectrum intravenous antibiotics were initiated and tailored to cultures.

Figure 2.

Pressurized pus flow from burr holes (A), a depression developed due to pressure on the sagittal sinus (B) and 48-hour postoperative MRV with restored flow and no filling defect (C). MRV, magnetic resonance venography.

The neurological examination remained intact throughout. A repeat MRV at 48 hours showed restoration of antegrade flow in the previously interrupted SSS segment, without filling defects (Figure 2C). The patient completed a prolonged intravenous antibiotic regimen and remained well at 1- and 2-year follow-up without recurrence.

Interpretation and implications. In adolescents with PPT and midline epidural disease, an MRV “flow gap” at the anterior SSS may represent reversible compression rather than thrombosis. This distinction is not merely semantic. First, it supports prioritizing source control – decompression and debridement – before considering anticoagulation. Second, a systematic early postoperative MRV (24–72 h) offers a low-risk means to reclassify the venous pathology. Third, avoiding empirical anticoagulation when the sinus rapidly re-expands may reduce hemorrhagic risk and simplify perioperative management.

Practice points:

1. 1. Obtain MRV preoperatively when PPT abuts the SSS or midline.

2. 2. Decompress early; treat infection aggressively with culture-guided antibiotics.

3. 3. Repeat MRV within 24–72 hours; if flow is restored and no thrombus is seen, anticoagulation can reasonably be withheld.

4. 4. Maintain long-term follow-up to ensure structural and infectious resolution.