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Radiol Oncol 2021; 55(3): 268-273. doi: 10.2478/raon-2021-0018
268
research article
MRI of the Morel-Lavallée lesion – a case series
Tajda Srot Volavc1, Mitja Rupreht1,2
1 Radiology Department, University Medical Center Maribor, Maribor, Slovenia
2 Medical Faculty, University of Maribor, Maribor, Slovenia
Radiol Oncol 2021; 55(3): 268-273.
Received 29 December 2020 
Accepted 16 February 2021
Correspondence to: Assist. Prof. Mitja Rupreht, M.D., Ph.D., Radiology Department, UMC Maribor, Ljubljanska 5, 2000 Maribor, Slovenia. 
E-mail: mitja.rupreht@ukc-mb.si
Disclosure: No potential conflicts of interest were disclosed.
This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Introduction. The aim of the study was to review the appearances of Morel-Lavallée (ML) lesions on magnetic 
resonance imaging (MRI).
Patients and methods. 14 patients diagnosed with the ML lesion on MRI were analysed retrospectively (mean age 
= 35 years). Mechanism of injury, time frame from injury to MRI, location, shape, T1 and proton-density fat-suppression 
(PDFS) signal intensity (SI), presence of a (pseudo)capsule, septations or nodules within the collection, mass effect and 
fluid-fluid levels were analyzed. The Mellado and Bencardino classification was utilized to classify the lesions.
Results. In most cases, mechanism of injury was distortion. Mean time frame between the injury and MRI was 17 days. 
Lesions were located around the knee in 9 patients and in the peritrochanteric region in 5 patients. Collections were 
fusiform in 12 patients and oval in 2 patients. 9 collections were T1 hypointense and PDFS hyperintense. 4 collections 
had intermediate T1 and high PDFS SI. 1 collection had intermediate T1 and PDFS SI. (Pseudo)capsule was noted in 3 
cases. Septations or nodules were found in 4 cases. According to the Mellado and Bencardino, collections were clas-
sified as seroma (type 1) in 9, subacute hematoma (type 2) in 1 and chronic organizing hematoma (type 3) in 4 cases.
Conclusions. Characteristic features of ML lesion include a fusiform fluid collection between the subcutaneous fat 
and the underlying fascia after shearing injury. Six types can be differentiated on MRI, with the seroma, the subacute 
hematoma and the chronic organizing hematoma being the commonest.
Key words: Morel-Lavallée; soft-tissue injury; hematoma; magnetic resonance imaging
Introduction
Morel-Lavallée (ML) lesion has initially been 
presented by a French surgeon Victor Auguste 
Francois Morel-Lavallée in 1863, who described it 
as fluid collection which dissects the subcutaneous 
fat tissue.1
In most cases, it is a post-traumatic, closed, de-
gloving soft-tissue injury caused by direct trauma 
or shearing forces, resulting in abrupt separation 
of skin and subcutaneous tissue from the underly-
ing fascia.2-4 Consequently, a dead space is formed, 
which can potentially fill with haemolymph, debris 
and fat, resulting in a formation of heterogeneous 
collection.2-3,5-6,7-9
Peritrochanteric region is particularly sensitive 
to this injury because of the increased mobility of 
the soft tissue in this area, the superficially located 
bone, strong underlying fascia lata attaching to the 
iliotibial band and a rich vascular plexus piercing 
the fascia lata.5,7,8
Clinically it usually presents as an enlarging pain-
ful swelling.2 Clinical presentation and the imaging 
techniques are keys to a diagnosis. Ultrasound (US) 
is an excellent imaging modality for the evaluation 
of superficial soft tissues and collections. However, 
owing to both high contrast resolution and demon-
stration of deep tissues, magnetic resonance (MRI) 
is a gold standard for the identification and evalua-
tion of the ML lesion.2-4,6-8,10,11
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ML lesion can present with various shapes and 
signal intensities in standard MRI sequences due 
to the different stages and contents of the lesions. 
This can lead to underrecognition and misinterpre-
tation of the ML lesions by the radiologists. In or-
der to prevent complications such as infections or 
extensive tissue necrosis it is essential to diagnose 
and manage the lesion in a timely manner.2-4,7,10
In the literature, several forms of ML lesions 
have been described. In 2005, an extensive six-stage 
imaging-based classification on the shape of lesion, 
signal intensity (SI) on T1 and T2-weighted images, 
presence of the fibrous capsule, contrast enhance-
ment and sinus tract formation capsule was pro-
posed by Melado and Bencardino (Table 1).11
A type 1 ML lesion is a seroma, exhibiting fluid-
like characteristics. It is seen as homogeneously 
hypointense on T1 and hyperintense on T2 MRI 
(Figure 1).5,12 It can be acute or chronic and is most-
ly noncapsulated.5,11
A type 2 ML lesion is a subacute hematoma, 
which appears homogenously hyperintense on 
both, T1 and T2 MRI.5,9,12 The cause of high T1 SI 
is the presence of methaemoglobin. In the early 
subacute hematoma, the methaemoglobin is first 
observed in the periphery. With time it becomes 
more homogeneously distributed.5,11,13  These le-
sions mostly have a hemosiderin-rich capsule on 
T1- and T2-WI. From time to time internal inhomo-
geneity can be seen, due to the fluid-fluid levels, 
internal septations and entrapped fat globules.5,13
Occasionally, patchy internal enhancement af-
ter intravenous contrast administration can be ob-
served due to the presence of capillaries, which can 
lead to false interpretation of the lesion as a soft-
tissue tumour. The subacute hematomas can be 
further divided in early and late subacute hemato-
mas. The early ones are more homogeneous, while 
the late ones often present with a fibrous capsule 
and are seen as heterogeneous.5,14
A type 3 ML lesion is a chronic organizing he-
matoma, with hypo- or intermediate SI on T1 and 
as heterogeneous intermediate on T2 sequences. 
The heterogeneous signal is seen due to the con-
tent of the lesion: hemosiderin granulation tissue, 
necrotic debris, fibrin and blood clots (Figure 2).11 
Because of neovascularization and granulation tis-
sue, patchy internal and peripheral enhancement 
can be seen on post-contrast MRI.5,12 These types of 
lesions may be surrounded by a hemosiderin-rich 
fibrous capsule.5,14
Type 4-6 ML lesions are the chronic ones, of-
ten presenting atypically. A type 4 ML lesion is 
a closed fatty tissue laceration with a perifascial 
dissection. It can be associated with or without a 
serous/haemorrhagic collection.5,11 The collection 
is seen with low T1 SI and high T2 SI. It is not sur-
rounded by a capsule and it enhances variably.5,14
A type 5 ML lesion is located perifascially and 
has a pseudonodular appearance. Occasionally, 
a peripheral enhancement and skin retraction are 
seen.5,11
A type 6 ML lesion is an infected lesion, it often 
presents with a thick capsule, internal septations, 
peripheral fluid leakage, inflammation of the adja-
cent fat tissue and fascia and sometimes even with 
an associated sinus tract.5,11 The aim of our study 
was to retrospectively analyse the series of patients 
with ML lesions based on the Mellado-Bencardino 
classification and evaluate its presentations on 
MRI.
FIGURE 1. Morel-Lavallee lesion type 1. A 33-years-old professional skier 2 weeks after 
a fall. A large fusiform collection (arrows) between the subcutaneous fat and fascia 
lata demonstrating low signal intensity (SI) on T1 WI (A) and high SI on proton density 
fat-saturated image (PDFS) (B) in coronal plane indicating clear fluid i.e. seroma.
FIGURE 2. ML lesion type 3. A 34-year-old male after a distortion. On axial proton-
density fat-suppression (PDFS) MRI (A) a fusiform fluid collection with hypointense 
debris is demonstrated between the deep subcutaneous fat and layers of medial 
patelofemoral ligament (arrows). On T1 weighted sagital image (B), in moderately 
hypointense collection several fat globules are visible (thin arrow).
A B
A B
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Srot Volavc T and Rupreht M / MRI of the Morel-Lavallée lesion270
Patients and methods
The study design was a single-center retrospective 
review, performed accordingly to the Declaration 
of Helsinki and approved by the local ethics com-
mittee. The search identified fourteen patients; ten 
male and four female. Their age ranged between 
11–67 years with the mean age 34.8 years. The 
examinations were performed with various MRI 
scanners. MRI protocol consisted of T1 sequence 
in at least one plane and proton density fat-sup-
pressed sequences (PDFS) in several planes. In ad-
dition, T2 sequence without fat suppression was 
utilized several times. Intravenous (I.V.) contrast 
was not administered in any case.
The mechanism of injury as well the time frame 
between injury and MRI were recorded, when 
provided. Additionally, the imaging reports and 
MRI images were reviewed. Also, the possible ad-
ditional imaging modalities were identified. The 
following characteristics of the MR-images were 
evaluated by the radiology resident (first author) 
and musculoskeletal (MSK) radiologist with 14 
years of experience (second author) in consensus: 
location, shape, signal intensity (SI), presence of a 
(pseudo) capsule, septations or nodules within the 
collection, mass effect and fluid-fluid levels.
Results
Mechanism of injury and time frame 
between the injury and MRI
In five patients out of fourteen (30.1%) the mecha-
nism was distortion, in 3/14 patients (21.4%) fall, 
2/14 (14.3%) were athletes without acute injury, 
1/14 (7.1%) patient kneeled and one (7.1%) was in-
jured in a motor vehicle accident. In 2/14 patients 
(14.3%), the mechanism of injury was unknown. 
For 11/14 patients (78.6%) the time frame be-
tween the injury and MRI was 4 days to 4 months, 
with mean time of 17 days. For 3/14 patients (21.4%) 
the time frame was unknown.
Additional ultrasound 
Only one patient (7.1%) had an ultrasound before 
the MRI. One patient (7.1%) had a follow-up ultra-
sound.
MRI characteristics
Location and shape
The collections were located around the knee in 
9/14 patients (64.3%) and in the peritrochanteric 
region in 5/14 (35.7%) patients.
The majority (12/14, 85.7%) of collections was 
fusiform and only 2/14 (14.3%) had oval shape.
MRI signal intensity and lesion classification
Most collections (9/14, 64.3%) were T1 hypointense 
and PDFS hyperintense (Figure 1). 4/14 (28.5%) 
collections had intermediate T1 and high PDFS SI 
(Figure 2). 1/14 (7.1%) collection had intermediate 
T1 and PDFS SI. (Pseudo)capsule was noted in 3/14 
cases (21.4%). Septations or nodules were found 
in 4/14 (28.5%) cases. No cases with mass effect or 
fluid-fluid levels were observed. Additionally, in 
5/14 (35.7%) cases fat globules were found. Also, in 
10/14 (71.4%) cases the oedema of subcutaneous fat 
was noted without lacerations.
The collections were classified according to the 
Mellado-Bencardino classification as seroma – type 
1 in 9/14 (64.3%), subacute hematoma – type 2 in 
1/14 (7.1%) and chronic organizing hematoma – 
type 3 in 4/14 (28.5%).
TABLE 1. MRI classification of Morel-Lavallee lesions according to Mellado-Bencardino12
Lesion type T1W T2W Morphology Other
Type 1 - Seroma Homogenously hypointense seroma
Hyperintense 
collection Laminar
No evidence of outer capsule 
formation
Type 2 – Subacute hematoma Homogenously hyperintense
Homogenously 
hyperintense Oval
Presence of methaemoglobin
Thin capsule formation
Type 3 – Chronic organizing 
hematoma Hypointense
Heterogeneous 
hypointense/
isointense
Oval
Thick capsule formation
Capsular and internal enhacement 
on postcontrast sequences
Type 4-Closed laceration Hypointense Hyperintense Linear No capsule formation
Type 5-Small, rounded 
pseudonodular appearance Variable Variable Round Variable capsule formation
Type 6-Superimposed infection Variable Variable Variable sinus tract Thick enhancing capsule
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Discussion
To our knowledge, the presented study is one of 
larger cohorts in the published literature, in par-
ticular with the focus on the MRI. ML lesions most 
commonly occur around the greater trochanter, al-
though they can be found around the knee, trunk, 
peri-scapular etc.2-3,5-7,10,11,15 Sometimes the collec-
tions may extend through thin sinus tract far from 
the original location (Figure 3). The location of the 
ML lesion around the knee was more frequent in 
our cohort than previously reported. Frequently, 
small fluid collections in the deep subcutaneous 
tissues around the knee joint are interpreted as 
simple seroma or hematoma whereas they could 
be also described as ML lesion. Alternatively, in 
the clinical practice, prepatellar fluid collections 
are commonly interpreted as a bursitis, which may 
represent the differential diagnosis. Prepatellar 
ML lesions often extend medially or laterally and 
proximally to the mid-thigh whereas a prepatellar 
bursitis does not extend beyond the mid-coronal 
plane and the boundaries of normal and slightly 
swollen bursa.16,17 The exact definition of loca-
tion might represent a challenge in the definition 
and classification of the ML lesions in the future. 
However, the distinction may not be clinically rele-
vant as treatment is often the same. A chronic hem-
orrhagic prepatellar bursitis may mimic a type 3 
ML lesion.14,18 The shapes of the lesions were in line 
with the previous reports.5 Septations and nod-
ules, as well as fat globules, were less frequent in 
the presented group than in a published literature5, 
probably owing to a small patient group. The pres-
ence of intralesional fat globules (Figure 4) is not 
pathognomonic, although they may be found in 
some subacute hematomas.19 However, their find-
ing may contribute to the characterization of the 
collection as the ML lesion.20,21 On the other hand, 
they are not among criteria of Mellado-Bencardino 
classification.
Most collections in the study group were clas-
sified as the Type 1 lesions. This could possibly be 
explained with the relative short time frame be-
tween the injury and the MRI. We could not find 
the time frame data in previous published reports. 
The results of less frequent type 2 and type 3 le-
sions are in line with other reports.5
We did not encounter type 3–6 lesions according 
to Mellado-Bencardino classification, possibly ow-
ing to their rarity, variable presentations on MRI, 
short time-frame between the injury and MRI, and 
a small patient group. Similar results were found 
in other small series.5
In the presented cohort, routine PDFS sequences 
were utilized as fluid-sensitive fat-suppressed se-
quences. The Mellado-Bencardino classification is 
based on T1/T2 MRI protocol, as it was most prob-
ably derived from MRI of soft tissue tumours as 
well as from other MSK protocols in mid-2000s, 
when it was introduced. The PDFS sequence was 
FIGURE 4. Fat globule and concomitant injury. In this 14-year-old boy with unknown time and mechanism of injury, a small fusiform fluid collection is 
visible at the right side between deep subcutaneous fat and fascia lata with low T1 (A) and high proton-density fat-suppression (PDFS) (B) SI (thin arrows) 
on coronal images. Note also a large fat globule in the lesion (short thick arrows). In addition, on the left side (C), an small avulsion of the sartorious 
tendon off the anterior superior iliac spine is visible (long thick arrow).
FIGURE 3. Extension of the Morel-Lavallée (ML)  lesion. Same patient as in the Figure 1. 
On axial proton-density fat-suppression (PDFS) images, a thin communication (thin 
arrows) between gluteus maximus muscle and the deep gluteal fat connects the 
primary lesion (thick short arrow) and another collection posteriorly (thick arrow). 
Note also the mild oedema signal of the gluteus maximus muscle and gluteal fat 
indicating contusions.
A B C
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mostly not utilized routinely in the MSK MRI at the 
time, however owing to its robustness it has been a 
MSK workhorse since 2010, when the routine role 
of non-fat-suppressed T2 sequence was reduced. 
Therefore, to be strict, the classification in the pre-
sented series could be characterized as »Mellado-
Bencardino related«. Furthermore, as in routine 
MSK MRI trauma settings, no contrast had been 
administered in the presented series. However, 
owing to other typical findings, follow-up exami-
nation with contrast was not indicated in any case. 
Modified MRI protocols, as well as not encounter-
ing types 3–6 lesions, might both imply the possi-
ble opportunity for an update and simplification of 
the Mellado-Bencardino classification to the three 
stages in the future. This should be verified in stud-
ies with larger patient cohorts and clinical correla-
tion.
The specific location between the subcutaneous 
tissue and the fascia, the imaging signs and knowl-
edge of the classification system may all be helpful 
in the differential diagnosis with other fluid-filled 
collections in the soft tissues.5 In addition to bursi-
tis, described above, other differential possibilities 
include soft tissue masses and other posttraumatic 
collections. Among soft tissue masses, sarcomas 
represent the most dangerous possibility which 
can mimic type 1 or 3 ML lesion. In short, sarco-
mas, as vascularized tumours, mostly demonstrate 
contrast enhancement, whereas collections do not. 
However, in most cases, particularly in trauma set-
ting, I.V. contrast is not administered, as it was not 
in the presented cohort, as mentioned. Therefore, 
caution is warranted and low threshold to follow-
up MRI with contrast or US Doppler examination 
(the role of US contrast in these settings is yet to 
be evaluated) should be set, particular in growing 
masses.
Other possible differential diagnoses include fat 
necrosis, where MRI signal depends on timing af-
ter trauma. It may appear spiculated or more lami-
nar22 and may sometimes mimic a type 4 ML le-
sion.11 Another possibility is pseudolipoma, which 
can develop after blunt trauma as well as iatrogenic 
after surgery and hematoma.11 On MRI, it usually 
presents as subcutaneous lipomatous mass with-
out capsule or contrast enhancement.23
Owing to their superficial location, most of 
ML lesions can be detected with ultrasound (US). 
Interestingly, only one patient in the presented 
cohort had had US examination performed before 
the MRI. This could be explained with the lack of 
data of possible US examinations performed out-
side our institution. Mostly, similar as on MRI, the 
US appearance depends on their age, often with 
heterogenous echogenicity. The latter depends on 
the degradation stage of the blood products; acute 
and subacute (up to a month) lesions will appear 
heterogeneous with irregular margins and lobular 
shape. Over the time, the blood products will liq-
uefy and become more hypoechoic. Chronic lesions 
(more than 18 months) are more often homogenous 
with smooth margins.7,20,21,24 MRI, however, enables 
more detailed analysis of deeper tissues and dem-
onstration of possible concomitant muscle, nerve 
and bone injuries (Figures 4, 5). In our opinion, 
it is therefore preferred imaging modality at least 
before possible invasive therapeutic procedures or 
clinical suspicion of possible extension in different 
compartments, larger collections, superinfections 
or unclear differential diagnosis.5 Nevertheless, US 
could be an excellent method for the follow-up of 
the lesion, particularly in conservatively managed 
cases, as well as in suspected complications after 
invasive treatment.
Computed tomography (CT) has minor role in 
the evaluation of the ML lesions. They may, how-
ever, incidentally show-up in the examinations, 
performed for the evaluation of possible bone inju-
ries. On CT, they may demonstrate with fluid-fluid 
FIGURE 5. Concomitant injuries. Same patient as in Figure 1 
and 3. In proton-density fat-suppression (PDFS) coronal image, 
a mild hyperintensity of adductor muscles is visible (thick arrow) 
indicating mild distension without fibre disruption. In addition, 
note secondary cleft sign (thin arrow) at the lower right 
edge of the pubic symphysis indicating possible injury of the 
rectus/adductor aponeurosis. In such case, a dedicated MRI 
examination might be warranted.
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Srot Volavc T and Rupreht M / MRI of the Morel-Lavallée lesion 273
levels and lower densities than simple hematomas 
owing to mixing of low-density lymphatic fluid.4 
Therefore, they may be easily overlooked, especial-
ly in the bone window.
Treatment of the ML lesion depends on the sta-
dium. It varies from compression banding, aspira-
tion or incision and evacuation, with or without 
injection of sclerosing agents.14,25
The lack of US data in the presented cohort rep-
resents a limitation of the presented study. Another 
limitation could be the lack of the data of further 
clinical and imaging management because most 
patients were outpatients who were lost to follow-
up. However, both were not primary purposes of 
the study.
Conclusions
Morel-Lavallée lesion results from the traumatic 
separation of the skin and subcutaneous fat from 
the underlying fascia where a fusiform fluid col-
lection is demonstrated on imaging. On MRI, six 
types of ML lesion can be differentiated, with the 
seroma, the subacute hematoma and the chronic 
organizing hematoma being the most frequent 
presentations. Knowledge of the most common 
locations, imaging signs and classification system 
may be helpful in the differential diagnosis. The re-
sults of the presented study, as well as the modified 
MRI protocols in the last decade, might suggest the 
opportunity for the possible update and simplifica-
tion of the Mellado-Bencardino classification.
References 
1. Morel-Lavalle M. Decollements traumatiques de la peaue et de couches. 
Arch Gen Med 1863; 1: 20-38, 172-200, 300-332.
2. Husein K, White B, Sampson M, Gupta S. Pictorial review of Morel-Lavallee 
lesions. J Med Imaging Radiat Oncol 2019; 63: 212-15. doi: 10.1111/1754-
9485.12854
3. Myrick KM, Davis S. Morel-Lavalee injury - a case study. Clin Case Rep 2018; 
6: 1033-9. doi: 10.1002/ccr3.1518
4. Diviti S, Gupta N, Hooda K, Sharma K, Lo L. Morel-Lavallee lesions review of 
patophysiology, clinical findings, imaging findings and management. J Clin 
Diagn Res 2017; 11: TE01-04. doi: 10.7860/jcdr/2017/25479.9689
5. De Coninck T, Vanhoenacker F, Verstaete K. Imaging features of Morel-
Lavallee lesions. J Belg Soc Radiol 2017; 101: 15. doi: 10.5334/jbr-btr.1401
6. Christian D, Leland HA, Osias W, Eberlin S, Howell L. Delayed presentation 
of a chronic Morel-Lavallee lesion. J Radiol Case Rep 2016; 10: 30-9. doi: 
10.3941/jrcr.v10i7.2698
7. McLean K, Popovic S. Morel-Lavallee lesion: AIRP best cases in radiologic-
pathologic correlation. Radiographics 2017; 37: 190-96. doi: 10.1148/
rg.2017160169
8. Riemer K, Haukenes O, Kozak A. Morel-Lavallee lesion. Tidsskr Nor 
Laegeforen 2019; 139. doi: 10.4045/tidsskr.18.0351
9. Gilbert BC, Bui-Mansfield LT, Schyuler D. MRI of a Morel-Lavellee lesion. Am 
J Roentgeol 2004; 182: 1347-8. doi: 10.2214/ajr.182.5.1821347 
10. Nair AV, Nazar PK, Sehkar R, Ramachandran PV, Moorthy S. Morel-Lavallee 
lesion: a closed degloving injury that requires real attention. Indian J Radiol 
Imaging 2014; 24: 288-90. doi: 10.4103/0971-3026.137053
11. Mellado JM, Bencardino JT. Morel-Lavallee lesion: review with emphasis 
on MR imaging. Magn Reson Imaging Clin N Am 2005; 13: 775-82. doi: 
10.1016/j.mric.2005.08.006
12. Mellado JM, del Palomar LP, Diaz L, Ramos A, Sauri A. Long-standing 
Morel-Lavallee lesions of the trochanteric region and proximal thigh: MRI 
features in five patients. Am J Roentgenol 2004; 182: 1289-94. doi: 10.2214/
ajr.182.5.1821289
13. Bush CH. The magnetic resonance imaging of musculoskeletal hemorrhage. 
Skeletal Radiol 2000; 29: 1-9. doi: 10.1007/s002560050001
14. Bonilla-Yoon I, Masih S, Patel DB, White EA, Levine BD, Chow K, et al. The 
Morel-Lavallee lesion: pathophysiology, clinical presentation, imaging fea-
tures and treatment options. Emerg Radiol 2014; 21: 35-43. doi: 10.1007/
s10140-013-1151-7
15.  Parra JA, Fernandez MA, Encinas B, Rico M. Morel-Lavallee effusions in the 
thigh. Skeletal Radiol 1997; 26: 239-41. doi: 10.1007/s002560050228
16.  Dye SF, Campagna-Pinto D, Dye CC, Shifflet S, Eiman T. Soft-tissue anatomy 
anterior to the human patella. J Bone Joint Surg Am 2003; 85: 1012-17. doi: 
10.2106/00004623-200306000-00005
17.  Yahyavi-Firouz-Abadi N, Demertzis JL. Prepatellar Morel-Lavallée effusion. 
Skeletal Radiol 2013; 42: 151-2. doi: 10.1007/s00256-012-1398-1
18.  Borrero CG, Maxwell N, Kavanagh E. MRI findings of prepatellar Morel-
Lavallée effusions. Skeletal Radiol 2008;  37: 451-55. doi: 10.1007/s00256-
008-0450-7
19.  Yu SJ. Magnetic resonance imaging of posttraumatic soft tissue disorders. 
Emerg Radiol 1996; 3: 181-94. doi: 10.1007/BF01507739
20.  Mukherjee K, Perrin SM, Hughes PM. Morel-Lavallee lesion in an adolescent 
with ultrasound and MRI correlation. Skelet Radiolog 2007; 36: 43-5. doi: 
10.1007/s00256-006-0122-4
21.  Neal C, Jacobson JA, Brandon C, Kalume-Brigido M, Morag Y, Girish G. 
Sonography of Morel-Lavallee lesions. J Ultrasound Med 2008; 27: 1077-81. 
doi: 10.7863/jum.2008.27.7.1077
22.  Chan LP, Gee R, Keogh C, Munk PL. Imaging features of fat necrosis. Am J 
Roentgenol 2003; 181: 955-9. doi: 10.2214/ajr.181.4.1810955.
23.  Theumann N, Abdelmoumene A, Wintermark M, Schynder P, Gailloud M-C, 
Resnick D. Posttraumatic pseudolipoma: MRI appearances. Eur Radiol 2005, 
15: 1876-80. doi: 10.1007/s00330-005-2757-2 
24.  Choudhary AK, Methratta S. Morel-Lavallée lesion of the thigh: character-
istic findings on US. Pediatr Radiol 2010; 40: 49. doi: 10.1007/s00247-010-
1587-9 
25.  Dawre S, Shashank L, Gupta S, Sreekar H, Gupta AK. The Morel-Lavallee 
lesion: a review and proposed algorithmic approach. Eur J Plast Surg 2010; 
35: 489-94. doi: 10.1007/s00238-012-0725-z