{
 "serie": "s401_T1_TSE",
 "n_imgs": 24,
 "s": 33.2,
 "respuesta": "**Series / technique:** Axial T1 TSE, right ankle, ordered from plantar (heel/calcaneus) to proximal (distal tibia/fibula, syndesmotic level). T1 only – no fluid‑sensitive sequence available, so oedema/fluid assessment is limited.\n\n**Findings**\n\n1. **Talar dome – medial (images ~15–17)**\n   Focal ill‑defined area of reduced/heterogeneous T1 marrow signal in the medial aspect of the talar body/dome, subchondral in location, with slight irregularity of the overlying articular margin. In a patient with remote inversion sprain and chronic pain this is most consistent with an osteochondral lesion of the medial talar dome (subchondral marrow change ± cyst). Confidence: **medium** (needs correlation with PD/T2 FS and sagittal/coronal planes).\n\n2. **Anterior talofibular ligament (images ~17–19, lateral malleolar level)**\n   The ATFL region between the anterior fibular tip and lateral talar neck appears thickened with intermediate signal and irregular contour rather than a thin, taut, uniformly low‑signal band – suggests chronic ATFL scarring/attenuation (chronic lateral ligament injury). Confidence: **low–medium** (axial T1 alone is limited).\n\n3. **Tibiotalar joint (images ~18–20)**\n   Small amount of intermediate‑signal material distending the anterior tibiotalar recess, likely a small effusion and/or anterior synovitis/capsular thickening (anterolateral impingement type change is possible given the history). Confidence: **low**.\n\n4. **Sinus tarsi / subtalar region (images ~11–13)**\n   Sinus tarsi fat largely preserved; a small focus of low T1 signal adjacent to the lateral calcaneal/talar process could represent a small subchondral cyst or sclerotic focus – indeterminate on T1 alone. Confidence: **low**.\n\n**Structures appearing normal (on this sequence)**\n- Achilles tendon: uniformly low signal, normal calibre, flat anterior margin; Kager fat pad preserved.\n- Peroneus longus and brevis: normal position posterolateral to the fibula, normal calibre, no split or subluxation seen.\n- Tibialis posterior, FDL, FHL: normal size and signal, no tenosynovitis appreciable on T1.\n- Anterior compartment tendons (tibialis anterior, EHL, EDL) and neurovascular bundles: unremarkable.\n- Distal tibia, fibula and calcaneus: no fracture line, no obvious marrow replacing lesion; syndesmosis alignment normal.\n- Plantar fascia and heel fat pad: normal.\n- Deltoid ligament: grossly intact low‑signal fibres medially (limited assessment).\n- No significant soft‑tissue mass.\n\n**Impression**\nProbable osteochondral lesion of the medial talar dome with chronic thickening/scarring of the ATFL and a small anterior tibiotalar effusion/synovitis – a pattern consistent with sequelae of previous inversion sprain. Tendons appear intact. Recommend correlation with fluid‑sensitive (PD/T2 FS) sequences and coronal/sagittal planes to confirm and stage the talar lesion."
}