45 David SuttonTHE SOFT TISSUES

DAVID SUTTON PICTURES

DR. Muhammad Bin Zulfiqar PGR-FCPS III SIMS/SHL

• Fig. 45.1 Accessory soleus muscle (a) on (A) sagittal T,-weighted SE and (B) transverse intermediate-weighted SE images. This accessory muscle is producing a soft-tissue mass anterior to the Achilles tendon (arrows) and was referred as a potential sarcoma. Symptoms of pain on exercise were due to claudication within the accessory muscle from poor vascular supply.

• Fig. 45.3 Inter and intramuscular lipoma between biceps brachii (superficial) and deeper brachialis muscles on sagittal (A) T,-weighted SE and (B) fat-suppressed proton density-weighted TSE images.

• Fig. 45.4 Postsurgical artefacts from an ACL reconstruction on coronal (A) spectral fat-suppressed proton density FSE and (B) STIR images. Note the more pronounced artefacts in A compared with B.

• Fig. 45.5 Soft-tissue infection with abscess formation (straight arrows) and osteomyelitis of the radius (small arrows) in a 23-year-old male on (A) coronal-oblique T2-weighted TSE, (B) coronal oblique, and (C) transverse post gadolinium-chelate T,-weighted SE image with fat suppression. There is extensive diffuse high signal throughout the flexor and extensor muscle compartments, subcutaneous tissues of the forearm and radius. Note the similar appearance of the T 2 - and, post contrast, Ti -weighted images.

Fig. 45.5 Soft-tissue infection with abscess formation (straight arrows) and osteomyelitis of the radius (small arrows) in a 23-year-old male on (A) coronal-oblique T2-weighted TSE, (B) coronal oblique, and (C) transverse post gadolinium-chelate T,-weighted SE image with fat suppression. There is extensive diffuse high signal throughout the flexor and extensor muscle compartments, subcutaneous tissues of the forearm and radius. Note the similar appearance of the T 2 - and, post contrast, Ti -weighted images.

• Fig. 45.6 SLAP tear (superior labral tear from anterior to posterior; open arrow) on contiguous coronal-oblique fat-suppressed T2 -weighted TSE images in a 40-year-old man who fell on an outstretched hand. There is also an associated and extensive partial tear on the bursal surface of supraspinatus tendon (small arrows) from bony impingement from a laterally down-sloping acromion (a). Note the excess fluid in the subacromial/subdeltoid bursa. h = humeral head; s = supraspinatus muscle.

• Fig. 45.7 Complete disruption of peroneus longus tendon (curved arrow) as it passes underneath the cuboid on parasagittal (A) T,-weighted SE and (B) T2 -weighted GE images. There is fluid signal from tenosynovitis surrounding the more proximal part of this tendon (small arrows). There is intermediate signal from the distal part of peroneus brevis tendon (open straight arrow) close to its insertion onto the base of the fifth metatarsal, which is a normal finding. Note that there is an associated osteochondral defect of the lateral talar dome (curved open arrow).

• Fig. 45.8 Focal increased signal (arrow) within the distal tendon of supraspinatus due to magic angle effect on a coronal-oblique proton density weighted TSE image. The T2-weighted image (not shown) confirmed a normal appearance to the tendon throughout its length.

• Fig. 45.9 Medially dislocated long head of biceps tendon (arrowhead) abutting onto the anterior glenoid labrum on a transverse fat suppressed T,-weighted post-arthrographic SE image. The intra-articular gadolinium-chelate returns a bright signal and highlights the torn and attenuated subscapularis tendon (short arrows). Note the empty bicipital groove (long arrow).

• Fig. 45.10A Diagram of tendon abnormalities: (A) normal; (B) thickened tendinopathy; (C) thinned tendinopathy; (D) intrasubstance longitudinal splitting-cleavage tears; (E) complete full thickness tear ((B) to (D) are partial tendon tears).

• Fig. 45.10B Cleavage tear (small arrows) in supraspinatus tendon on a coronal fat-suppressed T 2-weighted FSE image. There is fluid signal within the tendon extending into a large impingement cyst (C) on the lateral head of the humerus. Note the excess fluid within the glenohumeral joint and subacromial-subdeltoid bursa. Curved arrow = degenerative acromioclavicular joint.

• Fig. 45.11 Type I tendinopathy of tibialis posterior tendon (arrows) with intrasubstance cleavage tear (longitudinal splitting) and surrounding tenosynovitis on transverse (A) T,-weighted SE and (B) fat-suppressed proton density-weighted FSE images.

• Fig. 45.12 Type II tendinopathy of peroneus longus tendon (arrows) with surrounding tenosynovitis on sagittal fat suppressed proton-density TSE image. The peroneus brevis tendon with surrounding tenosynovitis is noted anterior to the peroneus longus tendon.

• Fig. 45.14 Pigmented villonodular synovitis (PVNS) on a sagittal GE image. There is a joint effusion with multiple areas of signal void from haemosiderin deposition and thickening of the synovium and plical fold within a distended suprapatellar bursa. Note the similar appearance as in Fig. 45.15.

• Fig. 45.15 Pigmented villonodular synovitis involving flexor hallucis longus tendon sheath (arrowheads) with involvement of the sinus tarsi (arrow) and subtalar joints on a sagittal T,-weighted image. Note the haemosiderin deposition. Similar appearance may be seen with chronic haemarthrosis (as in haemophilia), chronic rheumatoid arthritis, chronic TB arthritis, amyloidosis and gout.

• Fig. 45.16 Grade II tear of rectus femoris muscle (arrows) on transverse (A) intermediate-weighted SE, (B) T 2 -weighted SE, and (C) T 2 - weighted GRE images. Note that there is a perifascial rim of high signal together with diffuse signal within the rectus femoris muscle, best shown in C.

• Fig. 45.17 Muscle hernia of vastus lateralis (arrows) through a defect in the deep fascia of the right thigh demarcated by cod liver oil capsules on (A) coronal and (B) transverse T, weighted images.

• Fig. 45.18 Denervation atrophy of semimembranosus muscle (straight arrow) following removal of a lipoma on a transverse fat saturation T;-weighted spin echo (TSE 3000/100) image. The muscle is of high signal reduced in size. There is associated hypertrophy of gracilis muscle which accounted for the clinical referral as a possible tumor recurrence. There is incomplete fat saturation.

• Fig. 45.19 Large multiloculated early subacute haematoma (h) in the proximal thigh with high signal in (A) coronal T,-weighted SE and signal void in (B) transverse T2 -weighted TSE images due to intracellular methaemoglobin (short T, T2).

• Fig. 45.20 Late subacute haematoma within the thigh with a peripheral signal appearance due to extracellular methaemoglobin (short T, and long T2) on transverse (A) T2-weighted TSE and (B) fat-suppressed T,-weighted SE images.

• Fig. 45.21 Chronic haematoma, with heterogeneity in signal, involving the deep fascia of the medial calf indenting the medial gastrocnemius muscle on a coronal TI -weighted SE image. Note the peripheral signal void due to haemosiderin deposition.

• Fig. 45.22 Subacute myositis ossificans in the antecubital fossa in a 25 year old referred with a potential diagnosis of a dermoid/sarcoma (prior trucut biopsy was reported as being inconclusive) on (A) transverse Ti -weighted SE, (B) transverse T2 -weighted FSE, (C) sagittal post contrast T,-weighted SE images and (D) lateral radiograph of the elbow. The plain radiograph shows the characteristic peripheral ossification and multiple high-signal fluid-fluid levels from haemorrhage on the MR images.

• Fig. 45.22 Subacute myositis ossificans in the antecubital fossa in a 25 year old referred with a potential diagnosis of a dermoid/sarcoma (prior trucut biopsy was reported as being inconclusive) on (A) transverse Ti -weighted SE, (B) transverse T2 -weighted FSE, (C) sagittal post contrast T,-weighted SE images and (D) lateral radiograph of the elbow. The plain radiograph shows the characteristic peripheral ossification and multiple high-signal fluid-fluid levels from haemorrhage on the MR images.

• Fig. 45.23 Mature myositis ossificans (arrows) within gastrocnemius muscle in a 9-year-old girl on contiguous sagittal T 2 -weighted GE images. This mass was resected 2 years previously and referred as a possible osteosarcoma. Note the low-signal corticated rim with the central areas showing fatty marrow signal (same case as 45.85).

• Fig. 45.24 Exercise-induced compartment syndrome in the forearm musculature (arrows) involving the flexor and extensor compartments in a 43-year-old weight-lifter on (A) pre- and (B) post-exercise proton density weighted spoiled GE (FLASH) images.

• Fig. 45.25 Haemorrhagic pyomyositis (arrows) in brachialis muscle on transvers spin-echo (A) proton-density-weighted and (B) T 2 - weighted SE images. Note the more infiltrative pattern with little mass effect, as compared with the soft-tissue sarcoma in Fig. 45.32. The high signal from the lesion on the T2 -weighted image is not as intense as adjacent vessels, differentiating this from a haemangioma.

• Fig. 45.26 Large benign haemorrhagic popliteal cyst on sagittal (A) post contrast T,-weighted SE and (B) T2 -weighted TSE images demonstrating peripheral enhancement in (A) around the multiloculated cysts superiorly.

• Fig. 45.27 Synovial osteochondromatosis within the flexor tendon sheaths of the wrist on contiguous coronal T 2 -weighted GRE images. Note the multiple loose bodies of similar size within the fluid of the distended tendon sheaths.

• Fig. 45.29 Extrathoracic cystic hygroma wrapping around the right humerus (h) and involving the chest wall axilla in a 3-day-old neonate showing a multiloculated cystic lesion with fluid-fluid levels (arrows) due to haemorrhage on (A) transverse T,-weighted SE and (B) coronal T2 –weighted TSE images. This tumour was subsequently successfully removed.

• Fig. 45.30 Benign myxoma (m) within deltoid muscle mimicking a cyst (uniform low signal) on (A) coronal pre-contrast T,-weighted SE image but demonstrating in (B) heterogenous soft-tissue enhancement on postcontrast injection. Small myxoid liposarcoma within lateral abdominal wall musculature on (C) T,-weighted SE and (D) T 2 -weighted FSE images. The myxoid lesion is mimicking a cyst. Note it is not possible to differentiate between a benign or malignant tumour on MR characteristics, and although it was histologically a liposarcoma no fatty elements are demonstrated on MRI.

• Fig. 45.30 Benign myxoma (m) within deltoid muscle mimicking a cyst (uniform low signal) on (A) coronal pre-contrast T,-weighted SE image but demonstrating in (B) heterogenous soft-tissue enhancement on postcontrast injection. Small myxoid liposarcoma within lateral abdominal wall musculature on (C) T,-weighted SE and (D) T 2 -weighted FSE images. The myxoid lesion is mimicking a cyst. Note it is not possible to differentiate between a benign or malignant tumour on MR characteristics, and although it was histologically a liposarcoma no fatty elements are demonstrated on MRI.

• Fig. 45.31 Haemorrhagic malignant fibrous histiocytoma (MFH) on coronal (A) pre-contrast and (B) postcontrast T,-weighted SE images. Note a soft tissue tumour nodule (arrows) enhancing in (B) proximal to major haemorrhagic component.

• Fig. 45.32 Undifferentiated sarcoma in brachioradialis muscle in the proximal forearm on fat-suppressed transverse T1 -weighted SE (A) pre and (B) post contrast, and (C) T 2 -weighted TSE images showing a non-specific but malignant looking appearance.

• Fig. 45.33 Well-differentiated liposarcoma (atypical lipoma) in the medial thigh compartment on (A) coronal T,-weighted SE and (B) transverse T2 -weighted TSE images.

• Fig. 45.34 Morton's neuroma (arrows) in the web space between the third and fourth metatarsal heads on coronal (short-axis) (A) intermediate-and (B) T 2 - weighted dual echo images. This interdigital tumour is not a true neoplasm but a post-traumatic, degenerative fibrosing process around the plantar digital nerves. It is the most common entrapment syndrome in the foot and is frequently bilateral. The dense fibrous tissue making up this lesion is reflected in its low signal in (B).

45.35 Aggressive fibromatosis (desmoid) (t) in a 26-year-old male on (A) sagittal intermediate-weighted and (B) transverse T2 -weighted TSE images. Note the characteristic multiplicity and mixed composition of this tumour with an area of signal void from fibrosis together with more cellular soft-tissue components. There is a cod liver oil capsule (c) in place as a marker.

• Fig. 45.36 Soft-tissue cavernous haemangioma in an 11-year-old girl with 18-month history of a soft-tissue swelling exacerbated by exercise on transverse (A) T 1 -weighted SE and (B) fat-suppressed proton density weighted FSE images. Note the serpentine appearance of the vascular spaces infiltrating the muscles of the posterior and lateral compartments and subcutaneous tissues, together with some fat content typical of this lesion.

• Fig. 45.37 Malignant peripheral nerve sheath tumour (MPNST) in the posterior compartment of the thigh on a sagittal fat-suppressed T 2 - weighted TSE image showing the sciatic nerve (arrow) entering and exiting the heterogeneous mass

• Fig. 45.38 Ulnar nerve neuroma (arrows) within the medial triceps muscle on (A) coronal fat-suppressed proton density-weighted FSE and (B) transverse fat-suppressed T,-weighted SE postcontrast image. In A the neuroma demonstrates a thickened exiting ulnar nerve together with small ring-like areas with a higher periphery signal reflecting the fascicular bundles (termed the fascicular sign). The fascicular sign, optimally appreciated on proton density images, is usually seen in benign tumours, but if present in MPNST is only focal. In B the target sign is shown.

• Fig. 45.39 Two separate recurrent sarcoma masses (arrows) and a benign seroma (arrowhead) in the posterior compartment of the thigh on coronal (A) fat-suppressed T 2 -weighted TSE and (B) postcontrast T,-weighted SE. The patient had undergone prior surgery and post radiation treatment for a malignant fibrous histiocytoma. The post treatment change is producing the diffuse infiltrative abnormal signal with the tumour recurrences showing cystic nodular enhancing masses.

• Fig. 45.40 Soft-tissue abscess (arrow) with surrounding oedema and radiating linear strands (due to dilated lymphatics) on coronal spin-echo (A) proton density-weighted and (B) T 2 -weighted SE images. The absence of bone marrow involvement excludes osteomyelitis.

• Fig. 45.41 Soft-tissue infection within the posterior and adductor compartments of the left thigh in 37-year-old woman with no associated symptoms on a transverse postcontrast T 1 -weighted SE image. There is replacement of musculature with abscess formation and infiltrative oedematous signal, appearances different to that of a soft-tissue sarcoma.

• Fig. 45.48 Large welldefined lipoma of the thigh.

• Fig. 45.49 Peroneal muscular dystrophy. Atrophied muscle replaced by fat.

• Fig. 45.50 Lipohaemarthrosis of the shoulder. Fracture-dislocation of the humeral head. (Courtesy of Dr F. Starer.)

• Fig. 45.51 Cellulitis of the lower leg. Oedema and loss of tissue planes.

• Fig. 45.52 Calcified popliteal aneurysm..

• Fig. 45.53 Cavernous haemangioma of forearm with multiple phleboliths.

• Fig. 45.54 Chronic venous stasis with calcification.

• Fig. 45.55 Neural calcification in leprosy.

• Fig: 45.65. Pseudohypoparathyroidism causing nodular soft tissue calcification.

• Fig. 45.66 Calcification and ossification of the pinna in Addison's disease.

• Fig. 45.67 Calcified and ossified haematoma of the upper arm with an associated periosteal reaction.

• Fig. 45.70 (A,B) Dermatomyositis.

• Fig. 45.71 Tumoral calcinosis. A large soft-tissue swelling with calcification.

• Fig. 45.72 Myositis ossificans congenital. Note the plates of bone formed in the soft tissues of the back.

• Fig. 45.77 CT thorax. Atrophy of the right serratus anterior muscle is evident (arrow), secondary to previous lateral thoracic nerve damage.

• Fig. 45.78 Abdominal wall hernias. (A) Inguinal hernia (arrows). (B) Spigelian hernia (lateral to the rectus sheath) (*). (C) Lumbar hernia (arrows).

• Fig. 45.79 (A) Simple intramuscular lipoma with a central vascular structure. (B) Intramuscular lipoma interdigitating between the muscle fibres of gastrocnemius. (C) Atypical lipoma with irregular soft-tissue densities in the tumour, indistinguishable from a low-grade liposarcoma but histologically due to myxoid changes. (D) Intramuscular sarcoma (arrow).

• Fig : 45.81. Sural nerve neuroma

• Fig. 45.82 CT images of the hand. (A) Giant cell tumour encasing the flexor tendon of the little finger. (B) Lipoma of the palm, interdigitating between the flexor tendons and metacarpals. (C) Soft-tissue sarcoma arising in the hand.

• Fig. 45.84 Partial rupture of the right rectus femoris; note reduction in bulk of the right muscle and focal high- and low density areas centrally, representing fibrosis and fat infiltration (arrows).

• Fig. 45.86 Tumoral calcinosis, calcium-fluid levels (arrow) in a multiloculate collection around the shoulder in a patient in renal failure. (Courtesy of Professor J. E. Adams.)

• Fig. 45.87 Percutaneous biopsy of lung in right iliac fossa under MR control. Axial (A) and sagittal (B) views. Dotted lines represent computer-generated tracks of titanium biopsy needle. Histology-carcinoma of the colon.

• Fig. 45.88 (A) Sagittal gradient-echo scan post MnDPDP contrast showing a 3.5 cm-diameter lesion in upper part of the right lobe of the liver. (B) Real-time imaging with a virtual needle projected into the lesion from a chosen skin puncture site. (C) MR-compatible alloy needle being advanced into the lesion along the virtual needle path. The significant diameter of the apparent low signal of the needle represents metallic artefacts. (D) MR-compatible needle advanced directly into the metastatic lesion.

• Fig. 45.88 (A) Sagittal gradient-echo scan post MnDPDP contrast showing a 3.5 cm-diameter lesion in upper part of the right lobe of the liver. (B) Real-time imaging with a virtual needle projected into the lesion from a chosen skin puncture site. (C) MR-compatible alloy needle being advanced into the lesion along the virtual needle path. The significant diameter of the apparent low signal of the needle represents metallic artefacts. (D) MR-compatible needle advanced directly into the metastatic lesion.

• Fig. 45.89 (A) Fibroid pre-5-cm fibroid arising from the anterior lower uterine wall. Sagittal T2 -weighted image. (B) Fibroid with needles. T 2 - weighted image showing MR-compatible needles placed into the fibroid seen in Fig. 45.90 under MR guidance. Laser fibres are subsequently placed via these needles and heat is applied directly to the target fibroid using MR thermal mapping to control position and extent of healing. (C) Fibroid post. Same patient 4 months later showing marked subsequent reduction in fibroid size.

• Fig. 45.90 (A) Liver thermal ablation. Real-time MR thermal map produced by a subtraction process using T, signal loss. Red area indicates the extent of necrosis in this liver. Images are updated every 4 seconds providing an approximate in vivo thermometric read out which is used to control the (ablation). (B, C) Print outs at 4 second intervals.