Multimodality Imaging Appearance of Intrapericardial Paragangliomas

Paragangliomas are neuroendocrine tumors of the sympathetic and parasympathetic nervous system that originate from neural crest cells. Less than 1% of paragangliomas are found in the heart, originating from intrinsic cardiac ganglia cells in the posterior wall the atria, atrioventricular groove, and along the root of the great vessels. A 10-year review of our institution's database identified nine patients who had documented intrapericardial paragangliomas. We describe the multimodality imaging appearance of these tumors. The most common findings include embedment and wrapping around the great vessels and atrioventricular groove within the confines of the pericardium, markedly avid heterogeneous enhancement, distinct engorged neovascularization, and in large lesions, central low attenuation areas compatible with hemorrhage, necrosis, or cystic degeneration.

Case 272: Decubital Ischemic Fasciitis

HistoryA 92-year-old bedridden woman presented to the emergency department from an assisted living facility with fever, cough, and swelling over the right lateral hip. She had baseline dementia and frailty and had been bedridden for 4 years. She did not have any recent falls or history of trauma at the site of swelling. She had a history of diffuse large B-cell lymphoma that had been diagnosed and treated 7 years ago, and thoracoabdominal CT at last follow-up 3 years ago did not show any recurrence. Physical examination findings were unremarkable except for a painful hard and fixed mass measuring approximately 5 × 5 × 10 cm (in the transverse, anteroposterior, and craniocaudal directions, respectively) located at the right lateral superior thigh. The overlying skin was intact, without any color changes. Pertinent blood test results showed an increased white blood cell count of 13,000/µL (13 × 109/L) (normal range, 3700-11,000/µL [3.7-11 × 109/L]). The remaining hematologic and biochemical test results were normal. Abdominal and pelvic CT performed at presentation did not show any abnormal lymph nodes. Because chest radiography showed consolidation in addition to typical clinical picture, the patient was diagnosed with pneumonia and underwent antibiotic treatment for 3 weeks. US and Doppler US of the mass were performed. MRI was not performed because the patient had a pacemaker; instead, CT of the lower extremity was performed.

Predictors of Radiographic Osteoarthritis 2 to 3 Years After Anterior Cruciate Ligament Reconstruction: Data From the MOON On-site Nested Cohort

Background:

Multiple studies have shown that patients are susceptible to posttraumatic osteoarthritis (PTOA) after an anterior cruciate ligament (ACL) injury, even with ACL reconstruction (ACLR). Prospective studies using multivariable analysis to identify risk factors for PTOA are lacking.

Purpose/Hypothesis:

This study aimed to identify baseline predictors of radiographic PTOA after ACLR at an early time point. We hypothesized that meniscal injuries and cartilage lesions would be associated with worse radiographic PTOA using the Osteoarthritis Research Society International (OARSI) atlas criteria.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

A total of 421 patients who underwent ACLR returned on-site for standardized posteroanterior semiflexed knee radiography at a minimum of 2 years after surgery. The mean age was 19.8 years, with 51.3% female patients. At baseline, data on demographics, graft type, meniscal status/treatment, and cartilage status were collected. OARSI atlas criteria were used to grade all knee radiographs. Multivariable ordinal regression models identified baseline predictors of radiographic OARSI grades at follow-up.

Results:

Older age (odds ratio [OR], 1.06) and higher body mass index (OR, 1.05) were statistically significantly associated with a higher OARSI grade in the medial compartment. Patients who underwent meniscal repair and partial meniscectomy had statistically significantly higher OARSI grades in the medial compartment (meniscal repair OR, 1.92; meniscectomy OR, 2.11) and in the lateral compartment (meniscal repair OR, 1.96; meniscectomy OR, 2.97). Graft type, cartilage lesions, sex, and Marx activity rating scale score had no significant association with the OARSI grade.

Conclusion:

Older patients with a higher body mass index who have an ACL tear with a concurrent meniscal tear requiring partial meniscectomy or meniscal repair should be advised of their increased risk of developing radiographic PTOA. Alternatively, patients with an ACL tear with an articular cartilage lesion can be reassured that they are not at an increased risk of developing early radiographic knee PTOA at 2 to 3 years after ACLR.

Case 272

History A 92-year-old bedridden woman presented to the emergency department from an assisted living facility with fever, cough, and swelling over the right lateral hip. She had baseline dementia and frailty and had been bedridden for 4 years. She did not have any recent falls or history of trauma at the site of swelling. She had a history of diffuse large B-cell lymphoma that had been diagnosed and treated 7 years ago, and thoracoabdominal CT at last follow-up 3 years ago did not show any recurrence. Physical examination findings were unremarkable except for a painful hard and fixed mass measuring approximately 5 × 5 × 10 cm (in the transverse, anteroposterior, and craniocaudal directions, respectively) located at the right lateral superior thigh. The overlying skin was intact, without any color changes. Pertinent blood test results showed an increased white blood cell count of 13 000/μL (13 ×10⁹/L) (normal range, 3700-11 000/μL [3.7-11 ×10⁹/L]). The remaining hematologic and biochemical test results were normal. Abdominal and pelvic CT performed at presentation did not show any abnormal lymph nodes. Because chest radiography showed consolidation in addition to typical clinical picture, the patient was diagnosed with pneumonia and underwent antibiotic treatment for 3 weeks. US ( Fig 1 ) and Doppler US ( Fig 2 ) of the mass were performed. MRI was not performed because the patient had a pacemaker; instead, CT of the lower extremity was performed ( Fig 3a , 3b ). Figure 1: US image of the mass at the level of the greater trochanter. Figure 2: Doppler US image of the caudal portion of the mass. Figure 3a: (a) Axial unenhanced CT image of the lesion at the level of the greater trochanter. (b) Coronal unenhanced CT image of the mass at the level of the greater trochanter. Figure 3b: (a) Axial unenhanced CT image of the lesion at the level of the greater trochanter. (b) Coronal unenhanced CT image of the mass at the level of the greater trochanter.

Quantification of fat content in lipid-rich myxoid liposarcomas with MRI: a single-center experience with survival analysis

OBJECTIVE

To determine the fat content of myxoid liposarcomas (MLS) on MRI and to identify any association between lipid content and survival.

MATERIALS AND METHODS

The fat percentage of MLS diagnosed between January 2006 and December 2016 at a single institution was assessed by two radiologists on preoperative MR images. A Cox proportional hazard model was used to determine any association between tumor fat percentage and survival time. Tumor fat percentage was the single predictor in the model. A significance level of 0.05 was used. The Kaplan-Meier estimator was also used to provide a nonparametric estimate of the survivor function within the entire sample and within two patient subgroups consists of lipid-rich and lipid-poor tumors. Lipid-rich tumors were defined as any tumors showing more than 20% of fat on MRI. A 20% cutoff was determined arbitrarily.

RESULTS

Of the 43 cases identified through retrospective review, 8 tumors demonstrated ≥10% fat on MRI, and 4 tumors demonstrated ≥20% fat (highest fat percentage, 38%). There was no significant survival difference between patients with high tumor fat, which was defined as ≥20% fat, compared with those with little to no tumor fat.

CONCLUSION

Myxoid liposarcomas may demonstrate a higher fat content on MRI than has previously been reported in the literature. Increased tumor fat percentage in lipid-rich tumors was not found to be associated with increased risk of death. Radiologists must be aware of the existence of MLS lesions with higher fat content.

Gastrodoudenal Embolization: Indications, Technical Pearls, and Outcomes

The gastroduodenal artery (GDA) is frequently embolized in cases of upper GI bleed that has failed endoscopic therapy. Additionally, it may be done for GDA pseudoaneurysms or as an adjunctive procedure prior to Yttrim-90 (Y90) treatment of hepatic tumors. This clinical review will summarize anatomy and embryology of the GDA, indications, outcomes and complications of GDA embolization.

Osteoid osteoma of the hand and foot in children successfully treated with radiofrequency neurotomy probes

Osteoid osteoma is a common benign tumor that is typically found in young adults and children, usually in the long bones of the lower extremity. Radiofrequency ablation (RFA) under computed tomography guidance is the standard of care for symptomatic osteoid osteomas. However, patients with osteoid osteoma of the hand or foot are often treated with open surgery because of the risk of injury to vascular and neural structures from RFA. This risk is more pronounced in pediatric patients because of the small lesion size and proximity of lesions to important neurovascular structures. Here, we present 2 pediatric patients, one with an osteoid osteoma in the hand and the other with an osteoid osteoma in the foot. In both patients, a 22-gauge, 2.5-mm active tip ablation probe was used. The smaller ablation volume achieved with this probe protected neighboring neurovascular structures while effectively ablating the osteoid osteoma nidus. Based on our success in these cases, we recommend the application of this method for cases in which neurovascular proximity to the osteoid osteoma lesion makes ablation challenging.

Imaging features of mammary-type myofibroblastoma of soft tissue: a case series with literature review

Mammary-type myofibroblastoma (MTM) is a rare, benign neoplasm that is histologically identical to myofibroblastoma of the breast, but occurring in an extramammary site. The masses have been reported in superficial and deep soft tissue sites and visceral locations with the inguinal area and lower extremities are the most common. Most previous reports of MTMs have concentrated on clinical and pathological findings, with very limited information regarding imaging characteristics. Here, we describe three cases of MTM diagnosed at our institution, with a focus on imaging findings. We compare our findings with previously reported cases. Although MTM is rare, radiologists should be aware of this benign diagnosis as imaging characteristics can mimic those of liposarcomas and atypical lipomatous tumor/well-differentiated liposarcoma. Unlike those tumor types, MTM virtually never recurs post-resection, even when there are positive margins. Biopsy is necessary for proper diagnosis and recommended as an initial step to avoid overly aggressive treatment.

Incomplete Circle of Willis: A risk factor for mesial temporal sclerosis?

OBJECTIVE

The aim of this study was to investigate whether there may be a correlation between the anatomical variants of Circle of Willis (CoW) and presence/laterality of mesial temporal sclerosis (MTS).

METHODS

We retrospectively identified the CoW variants on Wada angiograms in 71 patients with pathologically proven MTS. Angiograms were interpreted by two radiologists independently and blinded to clinical data. We divided the anterior and posterior components of the CoW into functionally complete and functionally incomplete groups. We then sought its correlation with the presence and laterality of MTS.

RESULTS

No statistically significant relationship was found between the functional status of the anterior circulation and the laterality of the MTS (p=0.657). Relationship of the posterior incomplete circle to MTS was statistically significant on both sides (p=0.023 for the left, p=0.04 for the right), with an effect size moderate to large for the left side and moderate for the right side. Although the fetal variant appeared to be related to the ipsilateral MTS, it did not reach to a level of statistical significance (p=0.15).

SIGNIFICANCE

The study demonstrates a statistically significant association of the incomplete posterior circulation of the CoW to the presence of ipsilateral MTS. Further studies in larger patient populations may be needed to seek whether an incomplete circulation may facilitate development of MTS, especially affecting the watershed zones.

Minimally invasive treatments for perforator vein insufficiency

Incompetent superficial veins are the most common cause of lower extremity superficial venous reflux and varicose veins; however, incompetent or insufficient perforator veins are the most common cause of recurrent varicose veins after treatment, often unrecognized. Perforator vein insufficiency can result in pain, skin changes, and skin ulcers, and often merit intervention. Minimally invasive treatments have replaced traditional surgical treatments for incompetent perforator veins. Current minimally invasive treatment options include ultrasound guided sclerotherapy (USGS) and endovascular thermal ablation (EVTA) with either laser or radiofrequency energy sources. Advantages and disadvantages of each modality and knowledge on these treatments are required to adequately address perforator venous disease.

Inferior vena cava filter retrievals, standard and novel techniques

The placement of an inferior vena cava (IVC) filter is a well-established management strategy for patients with venous thromboembolism (VTE) disease in whom anticoagulant therapy is either contraindicated or has failed. IVC filters may also be placed for VTE prophylaxis in certain circumstances. There has been a tremendous growth in placement of retrievable IVC filters in the past decade yet the majority of the devices are not removed. Unretrieved IVC filters have several well-known complications that increase in frequency as the filter dwell time increases. These complications include caval wall penetration, filter fracture or migration, caval thrombosis and an increased risk for lower extremity deep vein thrombosis (DVT). Difficulty is sometimes encountered when attempting to retrieve indwelling filters, mainly because of either abnormal filter positioning or endothelization of filter components that are in contact with the IVC wall, thereby causing the filter to become embedded. The length of time that a filter remains indwelling also impacts the retrieval rate, as increased dwell times are associated with more difficult retrievals. Several techniques for difficult retrievals have been described in the medical literature. These techniques range from modifications of standard retrieval techniques to much more complex interventions. Complications related to complex retrievals are more common than those associated with standard retrieval techniques. The risks of complex filter retrievals should be compared with those of life-long anticoagulation associated with an unretrieved filter, and should be individualized. This article summarizes current techniques for IVC filter retrieval from a clinical point of view, with an emphasis on advanced retrieval techniques.

Defining the Collateral Flow of Posterior Tibial Artery and Dorsalis Pedis Artery in Ischemic Foot Disease: Is It a Preventing Factor for Ischemia?

BACKGROUND

Critical limb ischemia, a worldwide prevalent morbidity cause, is mostly secondary to vascular insufficiency due to atherosclerosis. The disease presents with intermittent claudication, which can progress to critical limb ischemia requiring amputation. Research has emphasized that the quality or existence of the pedal arch have a direct effect on wound healing and, therefore, on limb salvage, through the mechanism of collateral vascularization to the ischemic regions.

OBJECTIVES

This study aimed to determine the existence and, if present, grade of retrograde blood flow from plantar arch to dorsal foot artery (dorsalis pedis artery, DPA). The correlation between clinical symptoms and presence of collateral flow were also investigated.

PATIENTS AND METHODS

Study group consisted of 34 cases, which included patient group (n = 17, all male, mean age: 68 years) and control group (n = 17, all male, mean age: 66 years). After physical examination and lower extremity Doppler examination, spectral morphology of DPA flow was recorded, before and during manual compression of posterior tibial artery (PTA), for a period of 5 seconds. At the end, findings of Doppler ultrasound, computed tomography angiography, magnetic resonance angiography and, physical examination finding and symptomatology were gathered and analyzed.

RESULTS

In the patient group, 31 lower limb arteries, of total of 17 cases, were included. After compression maneuver, DPA in 11 cases (six right, five left) showed retrograde filling from plantar arch. This retrograde flow support was triphasic in three cases, biphasic in five cases, and monophasic in three cases. In other DPAs of these 20 limbs, PTA based retrograde collateral flow was not determined. In nine of these 20 limbs, with no or diminished retrograde filling, symptoms were worse than in other cases. Contrarily, only two of 11 limbs, with retrograde collaterals, have claudication during walking.

CONCLUSION

In cases with critical atherosclerotic disease of anterior tibial artery, PTA-based biphasic or triphasic retrograde collateral flow prevents ischemia, whereas monophasic support or no retrograde flow remains incapable.

In Vivo Evaluation of the Biomechanical Properties of Optic Nerve and Peripapillary Structures by Ultrasonic Shear Wave Elastography in Glaucoma

Background

Primary open-angle glaucoma is a multifactorial serious disease characterized by progressive retinal ganglion cell death and loss of visual field.

Objectives

The purposes of this study were to investigate shear wave elastography (SWE) use in the evaluation of the optic nerve (ON) and peripapillary structures, and to compare the findings between glaucomatous and control eyes.

Patients and Methods

A case-controlled study, including 21 patients with primary open-angle glaucoma and 21 age-matched control subjects, was carried out. All of the participants had comprehensive ophthalmological exams that included corneal biomechanical measurements with ocular response analyzer. In vivo evaluation of the biomechanical properties of the ON and peripapillary structures were performed with SWE in all participants. The Kolmogorov–Smirnov test was used to analyze the normal distribution of data. Differences of parameters in ophthalmologic data and stiffness values of patients with and without glaucoma were evaluated using the Mann-Whitney U test.

Results

There were no statistically significant differences between the glaucoma and control groups in terms of age (P > 0.05) and gender (P > 0.05). Corneal hysteresis was lower in the glaucoma group (P < 0.05). Corneal compensated intraocular pressure and Goldmann correlated intraocular pressure were higher in the glaucoma group (P < 0.0001 for both). The mean stiffness of the ON and peripapillary structures were significantly higher in glaucoma patients for each measured region (P < 0.05).

Conclusion

The study evaluated the biomechanical properties of the ON and peripapillary structures in vivo with SWE in glaucoma. We observed stiffer ON and peripapillary tissue in glaucomatous eyes, indicating that SWE claims new perspectives in the evaluation of ON and peripapillary structures in glaucoma disease.