CT and MR imaging features of adnexal torsion.

In adnexal torsion, the ovary, ipsilateral fallopian tube, or both twist with the vascular pedicle, resulting in vascular compromise. Unrelieved torsion is likely to cause hemorrhagic infarction as the degree of arterial occlusion increases. Therefore, early diagnosis is important to preserve the affected ovary. Adnexal torsion commonly accompanies an ipsilateral ovarian neoplasm or cyst but can also occur in normal ovaries, usually in children. Although ultrasonography is typically the initial emergent examination, computed tomography (CT) and magnetic resonance (MR) imaging may also be useful diagnostic tools. Common CT and MR imaging features of adnexal torsion include fallopian tube thickening, smooth wall thickening of the twisted adnexal cystic mass, ascites, and uterine deviation to the twisted side. Uncommon imaging findings in adnexal torsion that are specific to hemorrhagic infarction include hemorrhage in the thickened fallopian tube, hemorrhage within the twisted ovarian mass, and hemoperitoneum. Additional imaging findings that can suggest hemorrhagic infarction include eccentric smooth wall thickening exceeding 10 mm in a cystic ovarian mass converging on the thickened fallopian tube and lack of contrast enhancement of the internal solid component or thickened wall of the twisted ovarian mass. Early diagnosis can help prevent irreversible structural damage and may allow conservative, ovary-sparing treatment.     

Testicular torsion: Evaluation and management

Testicular torsion is described as the twisting of the spermatic cord resulting in acute pain and ischemia. This has a tendency to occur more frequently during adolescence and its cause is unknown. The most common signs and symptoms include red, swollen scrotum and acutely painful testicle, often in the absence of trauma. Nausea and vomiting are common. The most common conditions in the differential diagnosis include epididymitis, strangulated inguinal hernia, traumatic hematoma, testicular tumor, or testicular fracture. Physical examination techniques such as scrotal elevation can be helpful in differentiating between epididymitis and testicular torsion, but emergent imaging with Doppler ultrasound seems to be the most helpful in confirming the diagnosis. Radionuclide testicular scintigraphy with ^99mTc is helpful when past the acute phase (the first 12 hours) and vascular compromise has prolonged. The clinician may attempt to manually reduce the torsion, but many need to be immediately referred to a urologist for a surgical exploration. Long-term prognosis for a functional, nonatrophied testicle is improved the sooner the torsion is diagnosed and treated.     

Extralobar Pulmonary Sequestration with Hemorrhagic Infarction in a Child: Preoperative Imaging Diagnosis and Pathological Correlation

We describe a rare case of extralobar pulmonary sequestration with hemorrhagic infarction in a 10-year-old boy who presented with acute abdominal pain and fever. In our case, internal branching linear architecture, lack of enhancement in the peripheral portion of the lesion with internal hemorrhage, and vascular pedicle were well visualized on preoperative magnetic resonance imaging that led to successful preoperative diagnosis of extralobar pulmonary sequestration with hemorrhagic infarction probably due to torsion.     

Clinical and imaging features in lung torsion and description of a novel imaging sign

Purpose

We set out to identify the clinical and imaging features seen in lung torsion, a rare but emergent diagnosis leading to vascular compromise of a lobe or entire lung.

Methods

We retrospectively identified 10 patients with torsion who underwent chest CT. We evaluated each case for the presence of bronchial obstruction and abnormal fissure orientation. In seven patients who underwent contrast-enhanced CTs, we assessed for the presence of the antler sign, a novel sign seen on axial images demonstrating abnormal curvature of the artery and branches originating on one side.

Results

Five patients had right middle lobe (RML) torsion after right upper lobectomy, and the remaining occurred following thoracentesis, aortic surgery, or spontaneously. Chest CTs demonstrated bronchial obstruction in eight cases and presence of abnormal fissure orientation in four patients. The antler sign was present in three patients with whole-lung torsion and one patient with lobar torsion; vascular swirling was seen on 3-D images in all seven patients with contrast-enhanced CTs.

Conclusions

Lung parenchymal imaging findings in lung torsion may be non-specific. Identification of the antler sign on contrast-enhanced chest CT, in combination with other signs such as bronchial obstruction and abnormal fissure orientation, indicates rotation of the bronchovascular pedicle. The presence of this sign should prompt further evaluation with 3-dimensional reconstructions.

     

Ovarian and tubal torsion: imaging findings on US,CT, and MRI

Accurate diagnosis of adnexal torsion is often challenging, as clinical presentation is nonspecific and the differential for pelvic pain is broad. However, prompt diagnosis and treatment is critical to good clinical outcomes and preservation of the ovary and/or fallopian tube. Ultrasound (US) imaging is most frequently used to assess torsion. However, as computed tomography (CT) utilization in the emergency setting has increased, there are times when CT is the initial imaging test. Additionally, the nonspecific clinical presentation may initially be interpreted as gastrointestinal in etiology, where CT is the preferred exam. For these reasons, it is imperative to know the findings of adnexal torsion on CT as well as US. Magnetic resonance imaging (MRI) is helpful in cases where the diagnosis remains unclear and is particularly helpful in the young or pregnant patient with equivocal sonographic findings, as it provides excellent soft tissue contrast without ionizing radiation. This article will illustrate the findings of surgically confirmed ovarian and fallopian tube torsion on US, CT, and MRI, including those in the pregnant patient. Ovarian enlargement, adnexal mass, twisting of the vascular pedicle, edematous and heterogeneous appearance of the ovary, peripheral ovarian follicles, free fluid, uterine deviation towards the side of torsion, adnexal fat stranding, tubal dilatation, and decreased adnexal enhancement will be reviewed. Familiarity with the range of imaging findings across multiple modalities is key to improving the likelihood of timely diagnosis and therefore improved clinical outcomes.     

Plexiform nerve sheath tumor or vascular malformation—role of advanced MR neurography and diffusion tensor imaging

The authors report a vascular malformation mimicking a plexiform peripheral nerve sheath tumor. Three Tesla magnetic resonance neurography with high-resolution anatomic and advanced functional diffusion tensor imaging was helpful in evaluating full extent of the lesion and characterizing its internal architecture.     

Isolated tubal torsion: specific signs on preoperative computed tomography and magnetic resonance imaging

Isolated torsion of the fallopian tube is a rare cause of lower abdominal pain and commonly occurs after menarche. Prompt identification of this entity can prevent irreversible vascular damage, but the diagnosis is rarely made before surgery due to nonspecific clinical and imaging features. We report a case of isolated tubal torsion with specific imaging features on preoperative computed tomography and magnetic resonance imaging.     

Sonographic evaluation of peripheral nerve pathology in the emergency setting

High-resolution sonography has a growing role in both the diagnosis and management of traumatic and atraumatic peripheral nerve pathology. Sonography not only affords a cost-effective and time-efficient approach to interrogating long segments of peripheral nerves but also possesses unique advantages in terms of its dynamic, real-time nature with few clinical contraindications and limitations. In this review, we will initially discuss imaging techniques and characteristics of normal neural sonohistology, then address specific features and pitfalls pertaining to the spectrum of post-traumatic peripheral nerve injury. Additionally, we will highlight the more common sonographic applications in the clinical work-up of patients presenting with symptoms of dynamic neural impingement and entrapment. Finally, illustrative and clinical features of the more frequently encountered peripheral neural neoplastic pathologies will be addressed.     

Scintigraphic pattern in missed testicular torsion

The testicular scintigraphic findings of nine patients with surgically and pathologically proved torsion of the testis of over 24 hours duration are reviewed. In the delayed blood-pool images each showed the classical avascular twisted testicle with a variable peripheral rim of hyperemia. In the dynamic blood-flow phase, eight revealed a perceptible increase of vascular perfusion in the scrotal region on the affected side, in addition to the testicular radionuclide angiogram peculiarities previously described for missed testicular torsion. This pattern of perfusion was seen only in torsion of over one day duration. A low salvage probability is expected in these cases.     

Bilateral Vagus Nerve Neurolymphomatosis Diagnosed Using PET/CT and Diffusion-Weighted MRI

ABSTRACT: In neurolymphomatosis, malignant lymphocytes infiltrate the peripheral nervous system in the presence of a known or unknown hematological malignancy. This report describes the findings of diffusion-weighted MRI and F-FDG PET/CT in a 65-year-old man with hoarseness. Results revealed a mass with restricted diffusion on diffusion-weighted imaging in the right visceral vascular space, increased uptake of F-FDG, and other masses at distant peripheral nerves. Restaging PET/CT showed involvement of the right brachial plexus and right sciatic nerve. Biopsy and immunohistochemistry of the right vagus nerve and cervical lymphadenopathy revealed a diffuse large B-cell non-Hodgkin lymphoma.     

High-resolution MR neurography of diffuse peripheral nerve lesions

High-resolution MR imaging of peripheral nerves is becoming more common and practical with the increasing availability of 3T magnets. There are multiple reports of MR imaging of peripheral nerves in compression and entrapment neuropathies. However, there is a relative paucity of literature on MRN appearance of diffuse peripheral nerve lesions. We attempted to highlight the salient imaging features of myriad diffuse peripheral nerve disorders and imaging techniques for MRN. Using clinical and pathologically proved relevant examples, we present the MRN appearance of various types of diffuse peripheral nerve lesions, such as traumatic, inflammatory, infectious, hereditary, radiation-induced, neoplastic, and tumor variants.     

Combined PCL-ACL lateral and medial side injuries: treatment and results

The multiple ligament-injured knee is a complex problem in orthopedic surgery. These injuries may or may not present as acute knee dislocations, and careful assessment of the extremity vascular and neurologic status is essential because of the possibility of arterial and/or venous compromise, and nerve injury. These complex injuries require a systematic approach to evaluation and treatment. Physical examination and imaging studies enable the surgeon to make a correct diagnosis and formulate a treatment plan. Knee stability is improved postoperatively when evaluated with knee ligament rating scales, arthrometer testing, and stress radiographic analysis. Surgical timing depends on the injured ligaments, vascular status of the extremity, reduction stability, and the overall health of the patient. The use of allograft tissue is preferred because of the strength of these large grafts, and the absence of donor site morbidity.     

Evaluation of testicular viability by power Doppler ultrasonography in experimentally induced acute testicular torsion

RATIONALE AND OBJECTIVE: We sought to determine whether torsed testis viability can be evaluated by ultrasonography (US) including power Doppler US in an experimental model of acute testicular torsion. METHOD: Eighteen rats underwent unilateral 540 degrees testicular torsion and contralateral orchiopexy. Gray-scale and power Doppler US were performed 24 hours later. We evaluated echogenicity, intratesticular vascular flow, and testis size. Echogenicity and intratesticular vascular flow were quantitatively analyzed by using a visual scale and computer-based analysis. After US, detorsion was performed in torsed testes, and 6 days after detorsion testes were excised to determine testicular viability, which was determined using gross and microscopic findings. US findings before detorsion were correlated with testicular viability. RESULTS: At US performed 24 hours after testicular torsion, all viable testes (n = 7) were homogeneous and isoechoic versus contralateral testes. In nonviable testes (n = 11), lower (82%) and heterogeneous (73%) echogenicities were seen on gray-scale US. Intratesticular vascular flow was preserved in 86% of viable testes. In nonviable testes, no intratesticular vascularity was observed in 82%, and intermittent, peripheral blood flow was detected in the remaining 18%. Intratesticular focal lesions were observed in 45% of nonviable testis. Quantitative analysis showed a statistically significant difference between viable and nonviable testes in terms of testicular echogenicity and intratesticular vascular flow. CONCLUSION: Preoperative US including power Doppler examination can predict testicular viability in testicular torsion. Echogenicity of nonviable testes was found to be hypoechoic and inhomogeneous. Power Doppler examination showed no or intermittent peripheral blood flow in nonviable testes.     

Three-phase radionuclide bone scanning in evaluation of local radiation injury. A case report

The management of local radiation injuries is influenced by the degree of vascular compromise within the skin and underlying tissues. Other authors have used thermography and angiography in assessing the blood flow to radiation damaged tissues. This report describes the use of radionuclide imaging in the evaluation of a patient who developed necrosis of his distal digits following a radiation accident. In addition to determining the vascular status of the hands, imaging helped indicate an appropriate level for amputation.     

Peripheral nerve imaging: Not only cross-sectional area

Peripheral nerve imaging is recognized as a complement to clinical and neurophysiological assessment in the evaluation of peripheral nerves with the ability to impact patient management, even for small and difficult nerves. The European Society of Musculoskeletal Radiology, suggest to use ultrasound (US) for nerve evaluation due to the fact that, in sever anatomical area, magnetic resonance imaging is not able to give additional informations. US could be considered the first-choice approach for the assessment of peripheral nerves. The relative drawback of peripheral nerve US is the long learning curve and the deep anatomic competence to evaluate even small nerves. In the recent years, the role of US in peripheral nerve evaluation has been widened. In the past, nerve US was mainly used to assess nerve-cross sectional area, but now more advanced measurements and considerations are desirable and can boost the role of peripheral nerve US. Nerve echotexture evaluation was defined in 2010: The ratio between the hypoechoic and hyperechoic areas of peripheral nerves on US was called “nerve density”. For evaluation of patients who have peripheral neuropathies, the role of peripheral nerve is US wider than simple cross-sectional area evaluation. Quantitative measurements describing the internal fascicular echotexture of peripheral nerves introduce the concept of considering US as a possible quantitative imaging biomarker technique. The potential of nerve US has started to be uncovered. It seems clear that only cross-sectional area measurement is no more sufficient for a comprehensive US evaluation of peripheral nerves.     

Aortic dissection and malperfusion syndrome: a when, what and how-to guide

Malperfusion syndrome is a complication of aortic dissection caused by branch-vessel involvement and resulting in end-organ ischaemic dysfunction. Clinical diagnosis is mandatory, and imaging plays a critical role in confirmation and treatment planning. Radiologists must focus on detecting complications (findings of aortic dilation, rupture, organ ischaemia, etc.) and defining vascular compromise and associated malperfusion mechanisms. All these factors guide the multidisciplinary discussion concerning patient management and the suitability of endovascular treatment. Application of dedicated imaging protocols is mandatory in order to answer clinical and anatomical questions. Endovascular therapy has taken a predominant role in the therapeutic management of malperfusion syndrome with aortic fenestration, peripheral stenting and stent-grafting, all of which are procedures within the domain of expertise of current interventional radiologists. The purpose of this editorial is to present a when, what and how-to guide for all radiologists who encounter complicated aortic dissection.     

Normal brachial plexus: MR imaging

Magnetic resonance (MR) imaging of the brachial plexus was performed in the axial, coronal, and sagittal planes in seven volunteers. Normal structures were delineated by comparison with axial and sagittal cadaver sections and with gross dissection. Differentiation of soft tissues with MR imaging enabled the brachial plexus to be defined from surrounding muscle and vascular structures. Multiplanar imaging demonstrated anatomic detail not previously demonstrated with other radiologic modalities and provided excellent delineation of the components of the brachial plexus from the ventral rami to the peripheral nerve branches.     

Examination of postoperative peripheral nerve lesions with high-resolution sonography.

OBJECTIVE: Peripheral nerve lesions after surgery are common and are related either to direct compromise of the nerve by the surgical procedure (iatrogenic lesions) or to postoperative events such as scar formation. Despite a high sensitivity, electrodiagnosis may not reveal the exact location and cause of a nerve lesion. We hypothesized that high-resolution sonography could be helpful in diagnosing postoperative peripheral nerve lesions by direct visualization of the nerve and surrounding tissues. SUBJECTS AND METHODS: Eighteen patients with postoperative peripheral nerve lesions that were confirmed with clinical examination and electrodiagnosis were examined on sonography. Eight patients had lesions caused by direct nerve surgery, and 10 patients had undergone a previous orthopedic operation or open biopsy. Sonographic diagnoses were correlated with neurologic examinations and surgical findings. RESULTS: Reliable visualization of injured nerves on sonography was feasible in all patients. Axonal swelling of a nerve was diagnosed in three patients, direct compromise of a nerve by surrounding scar tissue or surgical implants was diagnosed in 10 patients, a neuroma was diagnosed in three, and insufficient surgical repair, in two. Sonographic findings were confirmed during surgery in all except one patient. CONCLUSION: In contrast to electrophysiologic tests, high-resolution sonography can show the exact location, extent, and type of a postoperative peripheral nerve lesion and the concurrent disease of surrounding tissues. Because the latter can often be the causative agent for the development of a lesion or the lack of improvement with conservative treatment, sonography yields important information that may not be obtained with other diagnostic modalities.     

F-18 FDG PET/CT findings of a case of sacral nerve root neurolymphomatosis that occurred during chemotherapy

Neurolymphomatosis (NL) is a rare, unique subtype of lymphomatous infiltration of peripheral nerves. Clinical/radiologic diagnosis of NL is challenging. We report F-18 FDG PET/CT findings of a case of breast diffuse large B-cell lymphoma, in which NL developed regardless of regression of systemic lesions during induction chemotherapy. FDG PET/CT showed characteristic findings of well-demarcated, linear abnormal FDG uptake along a sacral vertebral foramen, leading to diagnosis of NL, with the finding of thickened nerve roots on magnetic resonance imaging. Altered chemotherapeutic regimen resulted in disappearance of these abnormal FDG uptake, with recovery of neurologic symptoms. Peripheral nerve NL may occur during chemotherapy, and FDG PET/CT can be a useful imaging modality in diagnosis and monitoring of therapeutic response of this disease.     

Imaging of Soft Tissue Neoplasms in the Adult: Malignant Tumors

This review discusses the spectrum of malignant soft tissue tumors usually found in adults. Lesions most commonly identified in the pediatric population, as well as tumorlike masses, are not covered. Rather than presenting a complete review, the focus of this discussion is on common lesions and those lesions in which the diagnosis may be suggested on the basis of imaging. Diagnoses covered include malignant fibrous histiocytoma, fibrosarcoma, dermatofibrosarcoma protuberans, liposarcoma, synovial sarcoma, malignant peripheral nerve sheath tumor, leiomyosarcoma, aggressive vascular tumors, extraskeletal chondrosarcoma and osteosarcoma, lymphoma, and metastatic carcinoma.