Magnetic resonance imaging in glenohumeral instability

The glenohumeral joint is the most commonly dislocated joint of the body and anterior instability is the most common type of shoulder instability.Magnetic resonance (MR) imaging,and more recently,MR arthrography,have become the essential investigation modalities of glenohumeral instability,especially for pre-procedure evaluation before arthroscopic surgery.Injuries associated with glenohumeral instability are variable,and can involve the bones,the labor-ligamentous components,or the rotator cuff.Anterior instability is associated with injuries of the anterior labrum and the anterior band of the inferior glenohumeral ligament,in the form of Bankart lesion and its variants;whereas posterior instability is associated with reverse Bankart and reverse Hill-Sachs lesion.Multidirectional instability often has no labral pathology on imaging but shows specific osseous changes such as increased chondrolabral retroversion.This article reviews the relevant anatomy in brief,the MR imaging technique and the arthrographic technique,and describes the MR findings in each type of instability as well as common imaging pitfalls.

Endovascular management in abdominal visceral arterial aneurysms:A pictorial essay

Visceral artery aneurysms(VAAs) include aneurysms of the splanchnic circulation and those of the renal artery.Their diagnosis is clinically important because of the associated high mortality and potential complications.Splenic,superior mesenteric,gastroduodenal,hepatic and renal arteries are some of the common arteries affected by VAAs.Though surgical resection and anastomosis still remains the treatment of choice in some of the cases,especially cases involving the proximal arteries,increasingly endovascular treatment is being used for more distal vessels.We present a pictorial review of various intra-abdominal VAAs and their endovascular management.

Skeletal dysplasias: A radiographic approach and review of common non-lethal skeletal dysplasias

Skeletal dysplasias are not uncommon entities and a radiologist is likely to encounter a suspected case of dysplasia in his practice. The correct and early diagnosis of dysplasia is important for management of complications and for future genetic counselling. While there is an exhaustive classification system on dysplasias, it is important to be familiar with the radiological features of common dysplasias. In this article, we enumerate a radiographic approach to skeletal dysplasias, describe the essential as well as differentiating features of common non-lethal skeletal dysplasias and conclude by presenting working algorithms to either definitively diagnose a particular dysplasia or suggest the most likely differential diagnoses to the referring clinician and thus direct further workup of the patient.

Unusual presentation of Erdheim-Chester disease in a child with acute lymphoblastic leukemia

Erdheim-Chester disease(ECD) is an uncommon, nonfamilial, non-Langerhans cell histiocytosis, which involves skeletal system and soft tissue usually in middle aged and elderly patients. The characteristic radiologic features include bilateral, symmetric cortical osteosclerosis of the diaphyseal and metaphyseal parts of the long bones, or bilateral symmetrically abnormal intense 99 mTechnetium labelling of the metaphyseal-diaphyseal region of the long bones, and computed tomography scan findings of "coated aorta" or "hairy kidneys". ECD in childhood with osteolytic lesion is extremely rare. We describe an unusual case with an expansile lytic bone lesion at presentation in a case of acute lymphoblastic leukemia.

MR neurography in intraosseous median nerve entrapment

Intraosseous entrapment of the median nerve is an uncommon complication of elbow dislocation and fractures.The condition is seen to occur in adolescent age group with a remote history of trauma.We report two rare cases of type 2 intraosseous median nerve entrapment.Though the diagnosis of median neuropathy is made with clinical tests and neurophysiological studies,however exact site of entrapment and presurgical mapping of nerve is done accurately with MR neurography.Imaging thus plays a pivotal role in management of this condition.

Diagnosis of osteopetrosis in bilateral congenital aural atresia: Turning point in treatment strategy

Aural atresia is a rare congenital malformation of the external and middle ear. There are several syndromic associations of this anomaly with those involving the first and second branchial arches. Occurrence of aural atresia with sclerosing skeletal dysplasia is unknown and has never been reported. The coexistence of a sclerosing dysplasia can make the surgical treatment in aural atresia difficult and risky; and the auditory improvement may not be as expected. Moreover, internal auditory canal narrowing and hence sensorineural hearing loss in sclerosing dysplasia might add to the already existing conductive hearing loss in such patients. In this case report we have described an unknown association of bilateral microtia with sclerosing skeletal dysplasia(autosomal dominant osteopetrosis) and clinical implications of these two conditions occurring together leading to a change in the management plan.

Imaging of the pediatric thymus:Clinicoradiologic approach

The thymus is a lymphatic organ that undergoes dynamic changes with age and disease.It is important to be familiar with these physiological changes in the thymus gland to be able to identify pathology and make an accurate diagnosis.The thymus may be involved in multisystem disorders or show focal isolated lesions.The aim of this article is to review the radiological anatomy of the thymus,normal variants,and pathology including hyperplasia and benign/malignant lesions involving the thymus gland in the pediatric age group.We also propose an algorithmic approach for imaging evaluation of a suspected thymic mass on the basis of morphologic features.