Fat-fluid Level Research Articles

Is It Air or Fat? Chyluria as the Lesser Known Cause of Dark Fluid Levels within the Urinary System

Chyluria is caused by the development of the reno-lymphatic fistula leading to reflux of chyle in urine. The most common cause of chyluria is a parasitic infection, especially lymphatic filariasis; however, rarely chronic renal infections like tuberculosis can also cause chyluria. The presence of fat fluid level in the pelvicalyceal system, perinephric, retroperitoneal collections and in the urinary bladder on CT scan in a case of chronic pyelonephritis is an important indicator of the presence of the reno-lymphatic fistula. We describe clinical picture and CT images of a patient with chyluria showing fat fluid in abdominal collections.

The utility of standing knee radiographs for detection of lipohemarthrosis: comparison with supine horizontal beam radiographs.

Lipohemarthrosis is a key finding in acute trauma patients and indicates an intra-articular fracture. The horizontal beam lateral radiography with supine position is known to be the best technique to demonstrate knee lipohemarthrosis. Our main purpose was to compare the sensitivity of supine and standing lateral knee radiographs to detect lipohemarthrosis. In our retrospective study, consecutive patients with lipohemarthrosis on computed tomography of the knee between October 2019 and September 2021 were included. Fractured bone, the presence of lipohemarthrosis, and image quality in both standing and supine anteroposterior and lateral knee radiographs were evaluated. Interobserver reliability of the three observers was calculated. Fisher exact chi-square and z-proportion tests were used to compare lateral and anteroposterior knee radiographs. Krippendorff's Alpha and Kappa coefficients were used for inter-observer agreement. A total of 61 patients (38 men [62.3%], 23 women [37.7%]; mean age, 43years ± 17 [standard deviation]) were included. The most common type of fracture was isolated tibial fractures (n = 32; 52.5%). The sensitivity of showing lipohemarthrosis of standing lateral knee radiographs (95.5%) was higher than supine lateral radiographs (38.5%) (p < 0.001). While non-optimal image quality did not affect lipohemarthrosis detection on lateral radiographs (p > 0.99), it caused a significant decrease in the diagnosis of lipohemarthrosis on anteroposterior radiographs (p = 0.036). We found a good-excellent interobserver agreement in lipohemarthrosis detection. Standing lateral radiographs have higher sensitivity than supine lateral radiographs in detecting lipohemarthrosis and are beneficial for detecting lipohemarthrosis which indicates the presence of occult-evident intraarticular fracture in patients with knee trauma. Standing lateral knee radiographs offer a useful method for reducing the misdiagnosis of the occult intra-articular fractures by showing the fat-fluid leveling more clearly. Its advantages may be more prominent when the advanced imaging modalities are limited. • Fat-fluid level (lipohemarthrosis) is an important radiographic sign to assess patients with acute trauma. It almost always indicates an intra-articular fracture. • Our retrospective study results support that lipohemarthrosis sign could be observed more frequently in standing lateral knee radiographs than in supine lateral radiographs. • Knee trauma patients, when available, should be evaluated with standing lateral radiographs for the diagnosis of lipohemarthrosis.

Extra-capsular floating fat at the extremity: a review.

Extra-capsular floating fat may present in a variety of non-articular locations at the extremity. Manifestation of floating fat or fat-fluid level(s) outside of a joint is a marker of trauma or infection. Recognizing radiologic sign(s) of extra-capsular floating fat can aid radiologists to provide an informed differential diagnosis and facilitate clinical care. This review discusses the etiology, mechanisms, and imaging appearance of extracapsular floating fat in specific anatomic and non-anatomic locations at the extremity.

Rare Case Report of Mature Mesenteric Teratoma in a 35-Year-Old Female

Teratomas are germ cell tumors that usually occur in the gonads, and present in early age group. Mesenteric teratoma is rare. Patients with mesenteric teratoma may remain asymptomatic or may present with compressive symptoms. Teratomas contain derivatives of all three germ layers, hence may contain diverse tissues. Computed tomography (CT) scan is ideal to establish the diagnosis of mesenteric teratoma, and reveal fluid, fat, calcifications, fat-fluid level. This is a case of 35-year-old female, who presented with upper abdominal pain for 2 months. She underwent Computed Tomography (CT) scan which revealed large well circumscribed mass in left upper abdomen, containing fluid, fat, and globular calcifications. Size of the lesion was: craniocaudal dimension= 12 centimeter, transverse diameter = 10 centimeter, anteroposterior diameter = 10 centimeter. Patient was managed by complete surgical resection. Histopathological examination confirmed the diagnosis of mature teratoma of mesentery.

An Unusual Case of Bilateral Ovarian Dermoid Cyst in an Infertile Woman - A Case Report

Dermoid ovarian cysts or benign cystic teratomas are benign germ cell tumours which make up to 10 to 25 % of all ovarian tumours. These are usually found in women of reproductive age group with peak age between 25 and 45 years. Of all cystic tumours of the ovary, 5 to 10 % are dermoid cysts. These are bilateral in 12 to 15 % of cases.&#x0D; Mature cystic teratomas account for 10–20 % of all ovarian neoplasms and are the most common neoplasms in patients younger than 20 years of age. Mature teratomas are usually benign, but in 0.1-0.2 % of cases, they may undergo malignant transformation.[1]&#x0D; The word “teratoma,” initially coined by Virchow in 1863, originates from the Greek word teraton, meaning monster. The term “dermoid cyst” used much earlier for the same entity was coined by Leblanc, in 1831.[2] These are initially asymptomatic but can become symptomatic and present with symptoms like pain in the abdomen, anorexia, bloating, and an increase in size. Other complications are torsion, rupture, and infection. They are usually unilocular with smooth surfaces containing sebaceous material with hair, lined by squamous epithelium. Tissues like cartilage, bone, teeth, bronchial mucosa and thyroid tissue can be found in the wall. They have tissues from all three germ layers but ectodermal structures predominate. Diagnosis is usually made by ultrasound scan. Dermoid cysts have a characteristic appearance on ultrasound. Ultrasound findings include the presence of a Rokitansky nodule, fat fluid levels, dermoid mesh, and the “tip of the iceberg sign”.[3] CT scan and MRI can also be used. Management includes surgical excision by laparotomy or laparoscopy.

Persistent chyluria following renal cryoablation: A case report

Chyluria is a rare complication following renal intervention including partial nephrectomy and percutaneous ablation. To date, there are no reported cases of chyluria following renal cryoablation. An 82-year-old female patient at our institution underwent CT-guided percutaneous cryoablation for a renal cell carcinoma and presented with macroscopic fat in the urine 5 months after cryoablation. Presenting symptoms were polyuria, dysuria, and cloudy white urine. CT showed a fat-urine level in the ureter and bladder most consistent with chyluria. The patient experienced several episodes of presumptive lower urinary tract infection following diagnosis for which she was treated medically. Follow-up CT imaging 5 months post-diagnosis revealed persistent fat-fluid level in the collecting system and bladder. Operators performing renal cryoablation should be aware of the clinical and imaging manifestations of this complication.

Minimally invasive approach for a large, 25cm complex adnexal cyst at 17 weeks gestation

This video demonstrates a minimally invasive approach to the management of a large, complex adnexal cyst in pregnancy. A healthy 19-year-old G1P0 at 17 weeks gestation with a known 25.7 cm right adnexal cyst with fat fluid levels on MRI, consistent with dermoid cyst diagnosed in the first trimester, presented to the emergency room for acute onset right lower quadrant pain. She underwent a laparoscopic right ovarian detorsion and cystectomy and did well postoperatively. Fetal heart tones were confirmed prior to the start of the procedure. Entry into the peritoneal cavity was performed using the Hasson technique through a 3cm umbilical incision. Upon entry, the cyst was immediately visible due to its size and an Alexis retractor was inserted. A 12mm Hasson balloon trocar was advanced through the ovarian capsule and one liter of sebaceous contents was drained. An Endoloop was used to tie the base of the trocar to prevent spillage, and the trocar was removed. Now that the cyst was decompressed, a GelSeal Cap was attached to the Alexis retractor and the abdomen was insufflated. Using two additional 5mm trocar sites, we first detorsed the right ovary which was torsed three times around the utero-ovarian ligament. Afterwards, we performed a right ovarian cystectomy and the complex cyst was extracted through the GelPOINT. The ovary was preserved and replaced back into the abdomen. We copiously irrigated the abdomen to remove all the sebaceous contents. The 3cm umbilical fascial incision was closed and all three skin incisions were closed. Total operative time was two hours and one minute. Patient’s postoperative course was complicated by an adynamic ileus which was managed conservatively. Patient discharged in stable condition on postoperative day five. This video demonstrates that a minimally invasive approach is safe in the management of a large, complex adnexal cyst in pregnancy.

Tibial Plateau Fractures.

Tibial plateau fractures can result from direct trauma or indirect compressive forces. These injuries often result in significant soft tissue disruption, ligamentous disturbance in addition to bone fractures. Diagnostic imaging findings in plain radiographs include fat-fluid level in the suprapatellar bursa, malalignment of the femoral condyles and tibial edges, and increased trabecular density in the lateral epicondyle. Patients in whom a tibial plateau fracture is suspected with negative radiographs should have computerized tomography imaging performed. Most patients will require surgical intervention for fracture fixations. Primary long-term complication includes posttraumatic osteoarthritis because of the traumatic stress forces across the joint.

Long-term Results for Expectant Management of Ultrasonographically Diagnosed Benign Ovarian Teratomas.

To assess the natural history of ultrasonographically diagnosed benign ovarian teratomas in asymptomatic women. We conducted a retrospective observational cohort study of 408 women (mean age 36.6 years, range 14-81 years) diagnosed as having an ovarian teratoma by transvaginal ultrasonography (except eight who only had a transabdominal study done) between January 2003 and December 2013 at a single tertiary care institution. Six hundred thirteen women were diagnosed with ovarian teratoma of whom 205 were promptly treated surgically, leaving 408 patients followed conservatively with follow-up scans at 3 and 6 months from diagnosis and then yearly. The ultrasonographic diagnosis of a benign ovarian teratoma required at least one of the following features: a cystic mass with mixed echogenicity, thick band-like echoes, a fat-fluid level, or echogenic tubercle with posterior shadowing. Clinical, ultrasonographic, and histologic data (in case of surgery) were retrieved for analysis. During follow-up, 130 of 408 (31.8%) women underwent surgery. The main reason for surgery was the physician's recommendation according to our protocol (n=115). One patient had adnexal torsion. Most surgeries (112/130 [86.2%]) were performed within the first 5 years after diagnosis. The remainder (278/408) is still being followed (median time 45.6 months, range 6-147 months). The vast majority of these lesions had no change and women remain asymptomatic. Histologic diagnosis of tumors removed surgically revealed a benign ovarian teratoma in 103 of 130 (79.2%) of the women. There were two borderline tumors, four endometriomas, three fibromas, seven serous cysts, two mucinous cysts, two stroma ovarii, seven other benign, and no case of malignant tumor. Our results demonstrate that expectant management might be a reasonable option for managing asymptomatic women who receive a ultrasonographic diagnosis of a benign ovarian teratoma. The risk of undergoing surgery for this lesion decreases significantly after 5 years to follow-up. With careful observation, the risk of missing a diagnosis of malignancy is low.

What Does Fatty Mesenteric Lymphadenopathy Mean?

Question: A 56-year-old man with celiac disease presented to the emergency room with intermittent fever for the last month. There was no history of cough, urinary symptoms, or abdominal pain. He had a recent right colectomy for adenocarcinoma. His physical examination was unremarkable. Laboratory investigation showed anemia, and negative blood and urine cultures. Initial investigation with a postcontrast computed tomography scan of the abdomen showed multiple, coalescent, rim-enhancing, round cystic lesions with low-attenuation in the root of the small bowel mesentery (Figure A, arrows); some of them showed fat attenuation (Figure A, arrowheads). To better evaluate the findings, magnetic resonance imaging was performed. Axial T2-weighted magnetic resonance imaging demonstrated several cystic masses in root of mesentery with marked hyperintense signal (Figure B, arrows), some with fat–fluid levels (Figure B, arrowheads). Axial fat-suppressed T1-weighted image shows signal intensity consistent with fat inside the cystic lesions (Figure C, arrows), with fat–fluid levels (Figure C, arrowheads). What are the differential diagnoses? Look on page 16 for the answer and see the Gastroenterology website (www.gastrojournal.org) for more information on submitting your favorite image to Clinical Challenges and images in GI. As the patient had a history of colonic adenocarcinoma and celiac patients are at risk for lymphoma, the differential diagnoses included metastatic lymph nodes and lymphoma with necrosis.1Lucey B.C. Stuhlfaut J.W. Soto J.A. Mesenteric lymph nodes seen at imaging: causes and significance.Radiographics. 2005; 25: 351-365Crossref PubMed Scopus (111) Google Scholar Tuberculosis and Whipple’s disease were also possibilities, because they may present with hypoattenuating nodal disease owing to necrosis.1Lucey B.C. Stuhlfaut J.W. Soto J.A. Mesenteric lymph nodes seen at imaging: causes and significance.Radiographics. 2005; 25: 351-365Crossref PubMed Scopus (111) Google Scholar However, some of these lesions contained fat and a fat–fluid level, which increased the suspicion for cavitating mesenteric lymph node syndrome and decreased the probability of lymphoma, metastatic lymph nodes, and infection.2Huppert B.J. Farrell M.A. Kawashima A. et al.Diagnosis of cavitating mesenteric lymph node syndrome in celiac disease using MRI.AJR Am J Roentgenol. 2004; 183: 1375-1377Crossref PubMed Scopus (22) Google Scholar Cavitating mesenteric lymph node syndrome is a rare complication of celiac disease with <40 cases reported in the literature.2Huppert B.J. Farrell M.A. Kawashima A. et al.Diagnosis of cavitating mesenteric lymph node syndrome in celiac disease using MRI.AJR Am J Roentgenol. 2004; 183: 1375-1377Crossref PubMed Scopus (22) Google Scholar, 3Scholz F.J. Afnan J. Behr S.C. CT findings in adult celiac disease.Radiographics. 2011; 31: 977-992Crossref PubMed Scopus (36) Google Scholar Many of these cases also underwent surgery owing to the rarity of this syndrome and possibility of neoplasia.1Lucey B.C. Stuhlfaut J.W. Soto J.A. Mesenteric lymph nodes seen at imaging: causes and significance.Radiographics. 2005; 25: 351-365Crossref PubMed Scopus (111) Google Scholar In our case, because lymphoma could also be a diagnosis, the patient underwent surgery. Intraoperative view shows fluid with characteristic cream-like appearance in the peritoneal cavity that originated from the mesenteric cysts (Figure D). Histopathology revealed residual lymph node tissue on the cystic wall. A fibrous capsule and residual lymph node tissue were noted (Figure E, arrows). Atrophic cavitated lymph node was also observed (Figure F, arrow). Fat necrosis was compatible with the diagnosis of cavitating mesenteric lymph node syndrome. The patient was discharged with immunosuppression, but evolved with pancytopenia, was readmitted for pulmonary sepsis, and died.

Systematic evaluation of concomitant extensor tendon sheath injury in patients with distal intra-articular radial fractures in MDCT using the floating fat sign.

We aimed to evaluate the involvement of extensor tendon sheaths in a large MDCT study group of patients with distal intra-articular radial fractures using the floating fat sign. 603 MDCT scans of patients with acute intra-articular distal radial fractures (Frykman III-VIII) acquired between January 2005 and October 2011 were analysed in consensus by two radiologists. The extensor tendon sheath involvement was assessed for each extensor tendon compartment and visually graded from 0 to 2 based on the amount of fat-fluid levels. Extensor tendon sheath involvement with fat-fluid levels was observed in 71.0% of the distal radial fractures, mainly in the second or third compartment. The frequency and degree of tendon sheath involvement was not related to the fracture severity. There was no statistically significant difference in the frequency of tendon effusion between the CT scans acquired before or after closed reduction. Traumatic rupture of the extensor tendon sheaths with concomitant fatty effusion is a common finding in patients with distal intra-articular radial fractures. • Fat effusions in tendon sheaths are frequent in distal intra-articular radial fractures. • Fat effusions in tendon sheaths are caused by traumatic bone marrow spilling. • Effusions typically involve the second and third compartment simultaneously.

Ruptured intracranial dermoid cyst

A man in his late 60s presented with a sudden-onset headache, left-sided weakness and seizures. An unenhanced CT of the head showed a large low-attenuation lesion in his right frontal...

Fat-fluid level appearance of pseudochylothorax on CT

Fat-fluid level appearance of pseudochylothorax on CT

Extraosseous fat-fluid level on computed tomography and magnetic resonance imaging: A specific sign of hematogenous osteomyelitis

Extraosseous fat-fluid level is a rare but specific sign of hematogenous osteomyelitis. It results due to marrow necrosis due to infection with the release of fat globules and pus which extends into periosseous tissues through bony erosions. To form a fat-fluid level, the marrow necrosis has to be extensive which is not always present. However, when present and in appropriate clinical settings, it is fairly specific for hematogenous osteomyelitis. We describe radiographic, computed tomography, and magnetic resonance imaging findings in a case of osteomyelitis with extraosseous fat globules and fat-fluid level.

Primary cystic peritoneal masses and mimickers: spectrum of diseases with pathologic correlation.

Cystic lesions within the peritoneum have been classified classically according to their lining on histology into four categories-endothelial, epithelial, mesothelial, and others (germ cell tumors, sex cord gonadal stromal tumors, cystic mesenchymal tumors, fibrous wall tumors, and infectious cystic peritoneal lesions). In this article, we will proceed to classify cystic peritoneal lesions focusing on the degree of radiological complexity into three categories-simple cystic, mildly complex, and cystic with solid component lesions. Many intra-abdominal collections within the peritoneal cavity such as abscess, seroma, biloma, urinoma, or lymphocele may mimic primary peritoneal cystic masses and need to be differentiated. Clinical history and imaging features may help differentiate intra-abdominal collections from primary peritoneal masses. Lymphangiomas are benign multilocular cystic masses that can virtually occur in any location within the abdomen and insinuate between structures. Ultrasound may help differentiate enteric duplication cysts from other mesenteric and omental cysts in the abdomen. Double-layered wall along the mesenteric side of bowel may suggest its diagnosis in the proper clinical setting. Characteristic imaging features of hydatid cysts are internal daughter cysts, floating membranes and matrix, peripheral calcifications, and collagenous pericyst. Non-pancreatic psuedocysts usually have a fibrotic thick wall and chylous content may lead to a fat-fluid level. Pseudomyxoma peritonei appears as loculated fluid collections in the peritoneal cavity, omentum, and mesentery and may scallop visceral surfaces. Many of the primary cystic peritoneal masses have specific imaging features which can help in accurate diagnosis and management of these entities. Knowledge of the imaging spectrum of cystic peritoneal masses is necessary to distinguish from other potential cystic abdominal mimicker masses.

Presacral Retroperitoneal Teratoma in a 24-Year-Old Woman

Background: Teratomas are uncommon neoplasms made up of mixed dermal elements derived from the three germ cell layers, and characterized by the presence of any tissue type, often assuming bizarre morphology. Primary retroperitoneal teratomas account for 1%–11% of retroperitoneal neoplasms, and are most commonly found in neonates and young adults. Case: A case of large sacrococcygeal teratoma, in a woman operated on during the 1st year of life and again in early adulthood, is presented. Results: The patient's postoperative course was uneventful. In her case, histologic findings included epidermoid, respiratory, mucinous epithelial, and leiomuscular stromal components. Conclusions: the diagnosis of teratoma can be suggested by computed tomography (CT) findings demonstrating a complex mass with a well-circumscribed fluid volume, fat-fluid level, and calcifications. Transrectal ultrasound may be helpful in the diagnosis of the retroperitoneal location and the relationship with other pelvic structures. Complete surgical resection and careful histologic evaluation are mandatory, and have a prognostic value, because complete surgical resection of a benign teratoma has an excellent prognosis. (J GYNECOL SURG 30:158)

Non-displaced distal radius fracture with fat-fluid levels in the adjacent extensor tendon sheaths on MRI

We report a rare case of fat-fluid levels in the extensor tendon sheaths of the wrist on MRI. An 18-year-old female sustained a direct injury to her left hand while playing soccer. Plain radiographs showed soft tissue swelling with no definite fracture plane appreciated on the initial review of the images. The pain and swelling were severe and an MRI was obtained to evaluate for fracture and soft tissue injury. The MRI demonstrated a cortical defect near Lister's tubercle and multiple fat-fluid levels within the extensor tendon sheaths. This is the first reported case of fat-fluid levels within the extensor tendon sheaths on MRI, with only one previous case report of this entity on CT.

Part II - Dorsal wrist pain and swelling post trauma 2

DiagnosisTraumatic lipohaematoma of the extensor tendon sheaths(compartments 2–4) post distal radial fracture.DiscussionIn the same way that identification of a lipohaemarthrosisalerts the reading radiologist to the presence of an intra-articular fracture, the visualisation of a lipohaematoma ofthe tendon sheath after trauma may herald the presence offracture extending into an osseous groove for a tendon. Italso indicates injury to the tendon sheath, and raises thepossibility of associated tendon injury, which may warrantfurther assessment of the affected tendon with magneticresonance imaging.A 29-year-old man presented post cyclist vs car accident.CTshowed a comminuted distal radial fracture. As shown inFig. 3 of the case presentation, a fracture line cleavedcompletely through the base of Lister’s tubercle (largerarrow) with disruption of the floor of the fourth compart-ment by an acute angled sharp fracture fragment (smallerarrow). Fracture lines extended into the grooves for extensorpollicis longus (3rd extensor compartment) and extensordigitorum (4th extensor compartment). A separate fracturepassed into the grooves for extensor carpi radialis longusand brevis (2nd extensor compartment). The edges of thefracture fragments were sharply angulated and disrupted theosseous grooves for the 3rd and 4th compartment tendons.The medullary cavity of the distal radius appeared open tothe tendon sheaths of both the 3rd and 4th extensor compart-ments. An oblique sagittal fracture line was also seenextending from the volar surface of the radius through thearticular surface. A small lipohaemarthrosis of the radio-carpal joint was present. Further distally, within the tendonsheaths of the second, third and fourth extensor compart-ments prominent fat–fluid levels within the tendon sheathswere seen, accounting for the gross soft tissue swelling seenon the radiograph. The lipohaematoma was most volumi-nous within the distal third and fourth compartment sheaths,and comparatively small in the second compartmentsheaths. The average Hounsfield Unit density of the upper(and, by volume, larger) layer within the tendon sheaths wasapproximately −90, consistent with the presence of fat.Magnetic resonance imaging obtained 4 days after theinjury showed fat-fluid layers within the non-dependentaspect of the sheaths of the second, third and fourth com-partments. A layer of high T1 signal within the non-dependent aspect of the sheaths (part 1 figure 2 - arrow),which completely saturated on T2 fat suppression and cor-responded to the position of the −90 HU density materialseen on the CT, was present, confirming the presence of fat.The distal radial fracture is also evident on this image. Therewas focal irregular high T2 signal seen along the deep radialside surface of tendons of the extensor digitorum and exten-sor pollicis longus adjacent to the sharp fracture edges,consistent with tendon abrasion, but no frank split or rupturewas seen. The dependent portion of the lipohaematomashowed signal characteristics consistent with a mixture offluid and blood. Figure 4 of this article shows a fracture lineevident in the distal radius, which appears to have disruptedthe tendon sheath and is opening into the floor of the fourth

Massive ovarian cystic teratomas diagnosed at a rural Nepal camp

This case report presents the findings of significantly large sized (> 8 cm) symptomatic unilateral cystic teratomas in two perimenopausal patients in remote Nepal.Ovarian dermoid cysts consist of cystic, solid and fat tissue. Traditionally, cells differentiate along the various germ lines, essentially recapitulating various body tissues. The characteristic sonographic features include a dermoid plug, dermoid mesh, a fat‐fluid level and the “tip of the iceberg” sign.The presence of two or more of these typical features confidently supports an ultrasound‐based diagnosis of ovarian dermoid cyst.The presence of intratumoral hair, teeth, fat, and skin tissue revealed at surgery confirmed the initial ultrasound based diagnosis.

Diagnosis and triage of a patient with an extra-osseous fat fluid level

Extra-osseous fat fluid level is rarely seen in osteomyelitis, with only three magnetic resonance imaging (MRI) cases previously reported in the literature. The rarity of this finding is probably secondary to the extensive necrosis of bone marrow that needs to occur at a rapid phase for the fat to accumulate. However, an extra-osseous fat fluid level is a specific diagnostic sign of osteomyelitis in cases with otherwise equivocal imaging findings and should be reported as such, especially when associated with medullary bone destruction and in the absence of trauma.