✅ Knee MRI Mastery/Chap 1. Meniscus103 (Fig 1-E.02) Expected appearance of Low-grade partial meniscectomy. https://youtu.be/ryeg6TwVUbI https://youtu.be/SXRAadVysHc Low-grade partial meniscectomy For a low-grade partial meniscectomy, where less than 25% of the meniscus is removed, the postoperative evaluation uses the same criteria as the preoperative assessment, achieving up to 90% accuracy. To identify a tear in both preoperative and postoperative scenarios, the criteria include: A linear intrasubs.. 2024. 2. 9. (Fig 1-E.01) Preferential resection of the inner margin of the inferior leaf https://youtu.be/wTcKg69j5DU https://youtu.be/SXRAadVysHc ★ Normal signal intensity after partial meniscectomy ★ 1️⃣ Normal Meniscal Morphology After Partial Meniscectomy Following a partial resection, the meniscal morphology undergoes notable changes. There is a diminution of meniscal tissue, characterized by a smooth, regular appearance. Often, the free edge appears slightly blunted. It's not .. 2024. 2. 9. (Fig 1-D.03) Accessory iliotibial band–meniscal ligament https://youtu.be/Oxdr6hY3lB4 https://youtu.be/VHbQLFiofuc Accessory Iliotibial Band–Meniscal Ligament (AIML) ✅ Definition: The anatomic variation of the anterolateral fixation of the lateral meniscus to the ITB, which we have termed the “accessory iliotibial band–meniscal ligament” or “AIML.” ✅ Prevalence: An AIML was present in 13.3% of all patients (136/1019). ✅ Clinical Significance: The pres.. 2024. 2. 9. (Fig 1-D.02) Healed meniscal tears, Healed vs. Unhealed Meniscal Tears. https://youtu.be/WTx7BoVFTlc https://youtu.be/VHbQLFiofuc ★ Healed vs. Unhealed Meniscal Tears ★ 📌 Distinguishing Factors Tear location is a significant indicator for differentiating between healed and unhealed tears 1️⃣ Healed Tears Display low-signal-intensity strands bridging the tear on T2-weighted imaging. Characterized by a tear width of less than 2 mm. Visible only on intermediate-weighte.. 2024. 2. 9. (Fig 1-D.01) Progression of grade 2 signal intensity to meniscal tear https://youtu.be/qdUkDkT6gFk https://youtu.be/VHbQLFiofuc ★ MR Grade 2 Signal Intensity ★ 1️⃣ General Description Horizontal, linear intrasubstance signal increases from the meniscus's capsular periphery without reaching an articular surface. Lacks a distinct cleavage plane or tear. Typically asymptomatic in patients. Not a prognostic indicator for advancing to grade 3 signal intensity. ✅ Grade .. 2024. 2. 9. (Fig 1-C.18) Meniscal Ossicle https://youtu.be/SwMALyTRvHg https://youtu.be/VHbQLFiofuc ★ Meniscal Ossicle ★ Meniscal ossicles are indicators of potential meniscal tears, loss of articular cartilage, ACL injuries, or meniscal extrusion. Research using MRI has confirmed that meniscal ossicles, which can form in adults, are closely linked with posterior root tears of the meniscus, meniscus extrusion, and worsening osteoarthrit.. 2024. 2. 9. (Fig 1-C.17) Meniscal Flounce with meniscocapsular tear https://youtu.be/4TlrLMIVjm4 https://youtu.be/VHbQLFiofuc ✅ Meniscal Flounce and Its Associations: The most significant factor linked to meniscal flounce is a tear at the posterior horn of the medial meniscus (PHMM), followed by a tear at the meniscocapsular junction. When meniscal flounce is observed on knee MRI, it's essential to perform a thorough evaluation to check for potential coexisting .. 2024. 2. 8. (Fig 1-C.16) Meniscal Flounce and flounce-like fold https://youtu.be/k5lJ2yLaoZs https://youtu.be/VHbQLFiofuc ✅ Meniscal Flounce Summary: Meniscal flounce refers to a wave-like appearance of meniscus edges in sagittal MRI images. It occurs in about 0.2% to 0.3% of patients, mainly when the knee is flexed, and the free edge shows redundancy. While discussed in the context of the medial meniscus, it can also affect the lateral meniscus. The wave-li.. 2024. 2. 8. (Fig 1-C.15) Lateral Meniscal Extrusion https://youtu.be/uSt9VQdK9qA https://youtu.be/VHbQLFiofuc ✅ Meniscal Extrusion Summary: Medial meniscal extrusion is defined as meniscal tissue extending 3 mm or more beyond the tibial plateau edge (excluding osteophytes). For lateral meniscal body extrusion, a threshold of 2 mm is suggested. Medial meniscal extrusion alone should not be the sole diagnostic criterion. ✅ Lateral Meniscal Extrusio.. 2024. 2. 8. (Fig 1-C.14) Medial Meniscal Extrusion https://youtu.be/Bnw0ePs9EAo https://youtu.be/VHbQLFiofuc ✅ Meniscal Extrusion Overview: Meniscal extrusion occurs when the meniscus extends 3 mm or more beyond the tibial plateau edge. Substantial medial meniscus extrusion (> 3 mm) indicates severe meniscal issues like degeneration, extensive tears, and root involvement. Extrusion is commonly associated with posterior root tears but can also be.. 2024. 2. 8. (Fig 1-C.13) Parameniscal cyst versus ganglion cysts https://youtu.be/20PlDX-cB4A https://youtu.be/VHbQLFiofuc ★ Ganglia vs. Parameniscal Cysts ★ 1️⃣ Parameniscal Cyst Can appear similar to a ganglion but is usually smaller. Typically associated with an underlying meniscal tear. Diagnosis confirmed by showing a connection with an adjacent meniscal tear on MRI, regardless of the pulse sequence used. 2️⃣ Infrapatellar Ganglion ✅ Characteristics Well.. 2024. 2. 8. (Fig 1-C.12) Meniscal Cysts of lateral meniscus https://youtu.be/ydLLDKqICBs https://youtu.be/VHbQLFiofuc ★ Meniscal Cysts Overview ★ Meniscal cysts can sometimes show the same signal intensity as skeletal muscles on T1-weighted MRI images. This similarity can be attributed to the presence of hemorrhage or high protein content within the cysts. On T2-weighted images, these cysts may appear with low signal intensity, which could be due to the .. 2024. 2. 8. (Fig 1-C.11) Meniscal Cysts of medial meniscus https://youtu.be/ddzGp0w96S4 https://youtu.be/VHbQLFiofuc ★ Meniscal Cyst Overview: ★ 1️⃣ Intrameniscal Cysts: Appear as an increased signal within an enlarged meniscus. 2️⃣ Parameniscal Cysts: Appearance: Lobulated lesions with increased signal adjacent to the meniscus. Location: May extend along tissue planes. ✅ Medial Cysts: Can extend anteriorly to lie superficial to the Medial Collateral Li.. 2024. 2. 8. (Fig 1-C.10) Peripheral Meniscal Instability https://youtu.be/B9YVEff_c7E https://youtu.be/VHbQLFiofuc ✅ Hypermobile Lateral Meniscus: It is thought to result from the congenital absence of posterior capsular attachments (similar to Wrisberg-type discoid meniscus, but without discoid morphology) or from tears in the posterior capsular attachment, especially the popliteomeniscal fascicles. ✅ Unstable Discoid Meniscus (DM): Symptoms: In unst.. 2024. 2. 8. (Fig 1-C.08) Degenerated and torn lateral discoid meniscus https://youtu.be/4CET49Sx6XU https://youtu.be/VHbQLFiofuc 1️⃣ Discoid Menisci and Surgical Considerations: Detection & Treatment: Discoid menisci are usually found incidentally. Treatment is for those with symptoms and suspected tears, which are common in the complete discoid meniscus, often showing horizontal or longitudinal patterns. Surgical Recommendation: Meniscectomy is often recommended f.. 2024. 2. 8. (Fig 1-C.07) Meniscal shape deformation and torn lateral discoid meniscus https://youtu.be/z-ElsrteYGw https://youtu.be/VHbQLFiofuc Meniscal and Shape Deformation in Discoid Lateral Meniscus: Meniscal Deformation: Indicates peripheral detachment through abnormal infolding, buckling, and shifting. Shape Deformation: Signals early instability with surface changes, meniscal shifts, and development of meniscal megahorns. Important imaging signs include: Additional Key Fea.. 2024. 2. 8. (Fig 1-C.06) Ring-shaped meniscus versus bucket handle tear https://youtu.be/rZr3HY-aTYU https://youtu.be/VHbQLFiofuc 🧐The Watanabe classification outlines three types of discoid meniscus: 1️⃣Complete Variant: Characterized by a block-shaped meniscus covering the entire tibial plateau. 2️⃣Partial Variant: The meniscus covers 80% or less of the tibial plateau. 3️⃣Wrisberg Variant: Features a thickened posterior horn without the usual posterior attachments.. 2024. 2. 8. (Fig 1-C.05) Type III Wrisberg-type discoid meniscus https://youtu.be/FFrhoaLTkIA https://youtu.be/VHbQLFiofuc The Type III Wrisberg-type discoid lateral meniscus is characterized by: - Lack of popliteomeniscal fascicles and meniscotibial coronary ligament attachments. - Sole stabilization by the Wrisberg meniscofemoral ligament for the posterior horn. - Arthroscopically proven prevalence of less than 0.2%. - Generally normal or slightly thickened.. 2024. 2. 8. (Fig 1-C.04) Type II Incomplete discoid meniscus https://youtu.be/9PoZmZDe91s https://youtu.be/VHbQLFiofuc Type II: partial or incomplete discoid lateral meniscus A partial or incomplete discoid lateral meniscus that has a semi-lunar morphology, covering up to 80% of the surface of the lateral tibial plateau, with a normal posterior capsular attachment 1. MRI diagnostic criteria of Discoid meniscus Discoid meniscus is diagnosed when the body o.. 2024. 2. 8. (Fig 1-C.03) Type I Complete discoid meniscus https://youtu.be/HvfRIfFryPs https://youtu.be/VHbQLFiofuc 🤔Discoid Meniscus Overview: The discoid meniscus of the knee is a congenital or developmental variant with a thick, disc-like shape and central hypertrophy, leading to an increased width of the meniscal body. It typically lacks standard posterior meniscocapsular and ligamentous attachments, with the ‘discoid meniscus’ term covering a broa.. 2024. 2. 8. (Fig 1-B.51) Medial and Lateral Meniscocapsular Separations https://youtu.be/lsVTPU6e7p8 https://youtu.be/nKQsItyKAtM 🔴 Meniscocapsular Separation 🔹Disruption of capsular attachment of meniscus, in trauma, with irregularity, and increased signal intensity within meniscofemoral or coronary ligament on T2WI. 🔹Tear of the supporting meniscotibial (coronary) or meniscofemoral ligaments typically at the attachment to the meniscus 🔹In comparison to the medial .. 2024. 2. 8. 이전 1 2 3 4 5 다음
