Amar Udare, MBBS

A 7-year-old male presented with pain after falling on an outstretched hand.
 


Radiograph of the forearm shows subtle buckling involving the lateral cortex of the radius in its metaphysis (arrow in Figure 2).

Torus fracture is a type of incomplete fracture

 Commonly seen in long bones of pediatric patients.

 Most common mechanism of injury is indirect trauma, like fall on an outstretched hand (FOOSH).

 Axial load causes trabecular compression resulting in cortical buckling without an obvious fracture line.

 Elasticity of the developing bones in children causes buckling of the cortex rather than a fracture along a single plane as in adults.

• Seen as a curved disruption of the cortex and periosteum along the convex aspect of the bone along the metaphysis of long bones, most commonly distal radius.

Best seen when bone is imaged in profile as opposed to en face.

• Can be associated with mild overlying soft tissue.

• Rest and immobilization in the form a splint suffices in most cases.

• If the angulation is significant, manipulation may be needed.

• Occur when the force applied to a bone is sufficient to overcome the integrity of the cortex resulting in fracture of the convex surface and bucking of the concave surface.

• Needs active management and can take a long time to heal as they tend to occur in the diaphysis which are relatively slowly growing portions of the bone.

1. Solan MC, Rees R, Daly K. Current management of torus fractures of the distal radius. 

2. Uzelac A, Davis R. Blueprints Radiology. LWW. ISBN:1405104600.

3. Trauma X-ray - Upper limb gallery 1 - Greenstick and Torus fractures [Internet]. Radiologymasterclass.co.uk. 2017 [cited 6 August 2017]. Available from: http://www.radiologymasterclass.co.uk/gallery/trauma/x-ray_arm_1/fractures_11

4. Weerakkody Y. Torus fracture | Radiology Reference Article | Radiopaedia.org [Internet]. Radiopaedia.org. 2017 [cited 6 August 2017]. Available from: https://radiopaedia.org/articles/torus-fracture-1

5. The Radiology Assistant : Wrist - Fractures [Internet]. Radiologyassistant.nl. 2017 [cited 6 August 2017]. Available from: http://www.radiologyassistant.nl/en/p476a23436683b/wrist-fractures.html

Poll

A 7-year-old male presented with pain after falling on an outstretched hand.

Image IQ: 7-year-old with Pain after Fall

A 32-year old male presents with abdominal discomfort.

Plain and post-contrast CT at the level of the abdomen reveals multiple well-defined homogeneously enhancing lymph nodes in the peritoneum and retroperitoneal compartment. The vessels are seen coursing through this nodal mass with mild narrowing of caliber without invasion (sandwich sign).

Lymphomas are defined as the clonal malignant proliferation of a mature lymphocyte from a secondary lymphoid structure, a lymph node, or an extranodal structure. They are further classified into Hodgkin’s (HD) and Non-Hodgkin’s lymphoma (NHL).

• HD has a bimodal age distribution: First peak occurs in the middle to late 20s and the second peak after the age 50. Males are affected as commonly as females

• Prevalence of NHLs increases steadily with age throughout life. M:F 2:1

• Initial evaluation and follow-up of involvement of superficial lymph nodes, and for testicular involvement.

• Involved nodes are seen as well-defined, rounded homogenous lesions with loss of fatty hilum.

• However, US examination may be affected by the patient’s obesity or bowel meteorism, hence cross section imaging is necessary.

• Allows detailed evaluation of the mediastinum, chest wall, pulmonary parenchyma, and pleura or pericardium.

• Enlarged nodes with moderate homogeneous enhancement typically seen.

â Refers to the characteristic appearance of enlarged mesenteric lymphadenopathy enveloping fat and tubular structures at cross-sectional imaging resembling a sandwich or a hamburger.

â Sign is specific to mesenteric lymphomas as they can grow to a large size and can envelop fat, bowel, and vessels without causing clinical symptoms.

â Carcinomas, sarcomas, and carcinoid tumors originate within the small bowel and then spread to the mesenteric nodes and can quickly invade the bowel wall, causing perforation, hemorrhage, and widespread disease

• Particularly useful for evaluating the CNS disease.

• Owing to their cellular content, lymphoma deposits show restricted diffusion and have homogeneous post contrast enhancement.

• Provides comprehensive staging of the disease process and is also useful for monitoring response to therapy


Causes of mesenteric lymphadenopathy include lymphoma, carcinoma, sarcoma, carcinoid tumor, tuberculosis, Whipple disease, lymphadenopathy syndrome associated with acquired immunodeficiency syndrome (AIDS), and inflammatory bowel disease.
 

Image IQ: 32-year-old Male with Abdominal Discomfort

A 24-year-old male presented with history of pain in the knee following trauma. Radiograph and MRI images have been provided.


Plain radiograph shows a well-defined lytic lesion involving the distal metaphysis of the femur with a narrow zone of transition. The lesion reaches into the epiphyses; however, it does not reach up to the cortical surface. There is no periosteal reaction or cortical break. MRI reveals a well-defined multiloculated cystic lesion with fluid-fluid levels in the distal femur. The lesion does not reach up to the subarticular surface and there is no periosteal reaction/cortical break.


Aneurysmal bone cyst (ABC) is a non-neoplastic solitary lesion of bone consisting of a cystic cavity filled with blood. It is a misnomer as it is neither an aneurysm nor a true cyst but is made of blood filled channels. It occurs in patients between 5 and 20 years. The common symptom is pain. It affects the long tubular bones and spine. Lesions are located in the epiphyses and are eccentric.

• It is seen as an expanding, rapidly growing, saccular lytic, sharply demarcated by a thin subperiosteal shell

• It has multiple fine septae internally and sharply demarcated  bulging, scalloped borders

• Most lesions are metaphyseal; however, they extend to the epiphyseal end of the bone after the growth plate has closed

• It is associated with ballooning and thinning of the cortex (known as the "blown-out" appearance)

• Fluid-fluid levels in multicystic lesions are characteristic for ABC and are probably owing to settling of degraded blood products. Although this is classic for an ABC, these can also be seen in osteosarcoma, giant cell tumor, and chondroblastoma

• Individual chambers are separated by septae surrounded by a thin peripheral rim of low signal intensity on T1- and T2-weighted images. The septae may show enhancement on postcontrast scans; however, the lesion itself does not enhance

• Bone scan may show increased update peripherally with a photopenic center (doughnut sign)

1. Yochum T, Rowe L. Yochum and Rowe's essentials of skeletal radiology. Philadelphia, PA: Lippincott WIlliams & Wilkins; 2005.

2. Gailard F. Aneurysmal bone cust. Radiopaedia.org. Available from http://radiopaedia.org/articles/aneurysmal-bone-cyst. Accessed July 31, 2015

24-year-old male with history of pain in the knee following trauma.

Image IQ: 24 y/o, History of Knee Pain Following Trauma

 A 45-year-old female presented with vague pain in the abdomen. A USG was ordered, which revealed that both kidneys were enlarged and had innumerable cysts with minimal intervening parenchyma (Figure 1A and 1B). An ill-defined hyperechoic area with posterior acoustic shadowing was seen in the left kidney. The ureters and bladder were normal. A few similar cysts were also seen in the liver (Figure 2). The findings were confirmed on a plain CT scan which revealed bilateral nephromegaly and cysts in both kidneys and the liver. Multiple calculi were also seen in the in the left kidney (Figures 3-5). No cysts were identified in the pancreas and spleen. Features were suggestive of autosomal dominant polycystic kidney disease.

 Ultrasound image shows that the right and left kidney are enlarged in size and have innumerable cysts. No definite renal parenchyma is identified. Ill-defined shadowing is seen in the left kidney.

 Ultrasound of the liver shows cysts in the liver.

 Non-contrast CT scan axial sections reveal multiple cysts in the liver and kidney. Multiple calculi are also noted at the lower pole of the left kidney.

 Autosomal dominant polycystic kidney disease

Presents late in life: 30-50 years (as compared to ARPKD which presents in early childhood)

Autosomal dominant (90 percent); spontaneous mutations (10 percent)

Intracranial dolichoectasia: hypertension: up to 80 percent adults

Increased renal size with curvillinear wall calcification

"Swiss cheese" pattern: smoothly marginated radiolucencies in cortex and medulla seen on nephrographic phase

Shows increased renal size, innumerable cysts in both kidneys

Simple cysts will have anechoic walls with posterior acoustic enhancement

Hemorrhagic cysts show echogenic material devoid of blood flow

CT will also confirm the presence of cysts in other organs.

Post contrast: no contrast enhancement in simple cysts

No family history of renal cystic disease

Multiple renal and pancreatic cysts, pheochromocytomas, and frequently multiple and bilateral RCCs

Associated lesions include retinal angiomas and cerebellar hemangioblastomas

Multiple renal cysts and multiple fat containing angiomyolipoma

Cutaneous, retinal and cerebral hamartomas are associated

Development of multiple cysts in the native kidneys of patients on long-term hemodialysis

Affected kidneys are usually small, reflecting the chronic renal disease

Cysts are predominantly cortical and rarely exceed 2cm


1. Weerakkody Y, Gilliard. Autosomal dominant polycystic kidney disease.

http://radiopaedia.org/articles/autosomal-dominant-polycystic-kidney-disease-1

. Accessed November 25, 2013.
2. Federle M, Jeffrey R, Desser T, Anne V, Eraso A, et al. Diagnostic Imaging: Abdomen, 1st edition. Salt Lake City, UT: Amirsys; 2004.
3. Brant W, Helms C. Fundamentals of Diagnostic Radiology. 3rd Edition. Philadelphia: Lippincott Williams and Wilkins; 2005. Chapter 33, Adrenal Glands and Kidneys.

Articles

Case History: 45-year-old female with vague pain in the abdomen.

Autosomal Dominant Polycystic Kidney Disease

A 26-year old presented to the outpatient department with the chief complaints of headache and vomiting for the past six months.

 Axial sequences depicting a heterogeneous midline cystic mass is in the infratentorial region with its epicenter in the cerebellar parenchyma. Multiple intensely enhancing mural nodules are seen within the lesion. Some of the nodules showed a few irregular cystic/necrotic regions within.

 Axial image taken at a lower section shows a well defined cystic cavity with clear fluid appearing hyperintese on T2W sequence.

 Diffusion weighted images show that the lesion largely shows faciliated diffusion with few foci of restricred diffusion.

Spectroscopy shows elevate Ch/NAA ratio in the solid enhancing component of the lesion, especially in voxels 2 and 9.

 Perfusion sequences show that the lesion is hyperperfused as compared to the normal parenchyma.

  The patient underwent an MRI examination which showed a midline cystic mass is in the infratentorial region with its epicenter in the cerebellar parenchyma. The lesion was associated with multiple intensely enhancing mural nodules within it and a single similar nodule in the left cerebellar hemisphere adjacent to the lesion.

These lesions showed foci of bleeding within and around the lesion with multiple associated abnormal vessels. No peritumoral edema was seen. Some of the nodules showed a few irregular cystic/necrotic regions within it. The solid enhancing lesions were hyperperfused and showed restricted diffusion with elevated choline, reduced creatine and NAA with max choline/creatine ratio.

Features were suggestive of a hemangioblastoma. Orbits were unremarkable. Spine screening was shown which showed no additional lesions. Family history was abnormal. Patient underwent surgery for the solitary cerebellar lesion.

 Cerebellar hemangioblastoma is a benign neoplasm of uncertain origin that comprises approximately 7 percent of posterior fossa tumors in adults. It is the second most common neoplasm in the posterior fossa in adults second only to metastases.  It is associated with the autosomal dominant tumor-suppressor disorder von Hippel-Lindau (VHL).

Approximately 44 percent to 72 percent patients with VHL have a cerebellar hemangiobalstoma while 30 percent of hemangioblastomas can be attributed to VHL. The age at presentation is the fifth and sixth decades; however in VHL patients frequently at as young adults. Multiple hemangioblastomas are characteristic of VHL and constitute a major diagnostic criterion for the same.

MR is the imaging modality of choice. Characteristic MR criteria include cystic nature of the lesion, a peripheral pial-based mural nodule of solid tissue that enhances markedly with intravenous contrast, and large vessels within and/or at the periphery of the mass. On T1W images lesions appear isointense, while on T2W sequences the lesions appear hyperintense in keeping with their cystic nature. Flow voids are frequently noted either within or in the periphery of the lesion representing large feeding/draining vessels. The closest differential for hemangioblastoma is metastases, however high cerebral blood flow is characteristic of hemangioblastoma. Also perilesional edema is unusual in the former.                                    

Treatment primarily consists of surgical resection of symptomatic tumors.

Amar Udare, MD
Radiodiagnosis, Tata Memorial Hospital
Mumbai, India

Russell DS, Rubinstein LJ. Pathology of tumors of the nervous system, 5th ed. Baltimore: Williams & Wilkins, 1989

Leung RS, Biswas SV, Duncan M, et al. Imaging features of von Hippel-Lindau disease. RadioGraphics 2008;28:65-79

Atlas S. Magnetic Resonance Imaging of the Brain and Spine. 4th edition. Lippincott Williams & Wilkins. 2008

Cerebellar Hemangioblastoma

A 72-year-old female presented with chief complaints of acute pain in abdomen for the past few days. The patient had been diagnosed of a periampullary carcinoma for which she had undergone ERCP and stent placement to relieve the obstructive jaundice.
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  A CT scan was performed which showed ill-defined circumferential wall thickening in the periampullary region with grossly dilated CBD (measuring 2.0cm in diameter), dilated pancreatic duct (measuring 5mm) and a few periportal and paraaortic lymph nodes. There was mild intrahepatic biliary radical dilatation with the CBD stent in situ. The pancreatic head and uncinate process appeared bulky and mildly hypodense with evidence of a rim of fluid surrounding it and shaggy margins. Soft tissue stranding was seen surrounding these structures and extending into root of mesentery. The features were suggestive of acute edematous pancreatitis in the region of pancreatic head and uncinate process.

Periampullary carcinoma with ERCP-induced pancreatitis

 Endoscopic retrograde cholangiopancreatography (ERCP) is being widely used not only for diagnostic but also a therapeutic tool for the management of various benign and malignant conditions affecting the hepatobilliary tract. The common complications are pancreatitis, hemorrhage, cholangitis and duodenal perforation. Pancreatitis is seen in 5 percent of the diagnostic and 10 percent of therapeutic cases. The diagnostic criteria for pancreatitis include two out of the following three:

1. Abdominal pain for more than 24 hours after the procedure
2. Elevated levels of serum pancreatic enzymes three times the normal value.
3. Imaging study supporting the diagnosis (CT or MRI)

CT is the primary modality used for the diagnosis of the condition. The salient features include focal enlargement of the gland with heterogeneous post contrast enhancement, hypoattenuation in areas of necrosis and peri-pancreatic fat stranding.  Air bubbles are noted in the necrotic pancreatic tissue if the area gets infected. Complications like pseudocyst, pseudoaneurysms, ascites and pleural effusion. The management protocol is same as that of any other cause of pancreatitis. Owing to the lack of specificity of pain and biochemical studies (serum amylase/lipase) in patients who have undergone ERCP, imaging plays a crucial role in diagnosis which can aid early management and avoid unfavorable consequences.

Radiodiagnosis, Tata Memorial Hospital
Mumbai, India

Pannu HK, Fishman EK. Complications of endoscopic retrograde cholangiopancreatography: spectrum of abnormalities demonstrated with CT. RadioGraphics2001; 21: 1441–1453

Badalov N, Tenner S, Baillie J:  The Prevention, Recognition and Treatment of Post-ERCP Pancreatitis. JOP. J Pancreas (Online) 2009, 10(2):88-97.

Smith G, Lieberman G. An Atlas of Complications of ERCP [Internet]. Gillian Lieberman, MD ;March 2012 [cited 2012 Sep 19].Available from 

http://eradiology.bidmc.harvard.edu/LearningLab/gastro/Smith.pdf

Cohen SA, Siegel JH, Kasmin FE. Complications of diagnostic and therapeutic ERCP. Abdom Imaging 1996; 21:385–394.

Banks PA, Freeman ML; Practice Parameters Committee of the American College of Gastroenterology. Practice Guidelines in Acute Pancreatitis.  Am J Gastroenterol 2006; 101:2379-2400.

Periampullary Carcinoma with ERCP-induced Pancreatitis

 A 34-year-old male presented to the outpatient department with the chief complaints of gradual enlargement of the hands and feet. On examination there was enlargement of hands and feet, and coarse features with broad nose, frontal bossing and protruding jaw line.

 Radiograph of the hand showing generalised increased soft tissue, broadened phalangeal tufts, minimal widening of the metacarpal spaces and few carpal cysts. The base of the terminal phalnges appears more broad giving the appearance of a spade like deformity.The laboratory results showed an increase in the growth hormone.

A skeletal survey was hence ordered. Radiograph of the foot showed increased in the heel pad thickness.

 Radiograph of the foot, lateral view, shows increase in the heel pad thickness.

Radiograph of the skull (lateral and frontal views) shows thickening of the cranial vault, enlarged frontal sinus, prominence of the occipital protuberance, prominent supra-orbital ridge, widened space between the upper incisors and an enlarged mandible.

 Lateral radiograph of the skull depicting the increased size of the sella turcica.

A provisional diagnosis of a pituitary adenoma causing acromegaly was made which was further confirmed on MRI examination. The tumor was later resected via the transphenoidal route.

 Acromegaly is a disorder caused due to the overproduction of growth hormone after fusion of the epiphyses, i.e. after skeletal maturity. It is most commonly due to a GH-secreting adenoma in the anterior pituitary gland. Owing to the increased production of growth hormone there is marked connective tissue hyperplasia resulting in soft tissue swelling leading to increased heel pad thickness, increased shoe or glove size, ring tightening, characteristic coarse facial features, and a large fleshy nose. The onset is insidious and on examination there is frontal bossing, increased hand and foot size, mandibular enlargement with prognathism due to acral bony overgrowth.

The earliest manifestations include enlargement of hands and feet and coarsened facial features. On a plain radiograph the features include thickening of the cranial vault, widening of the sella turcica, increased n the size of the paranasal sinuses and hyperpneumatisation of the mastoid and overgrowth of the mandible. In the hand the changes include enlargement of the base of the distal phalanges and spur like projections from the tuft leading to a spade like appearance. Also due to cartilage overgrowth there is widening of the joint spaces on the metacarpophalangeal joints. The heel pad thickness which is the distance from the posteroinferior surface of the calcaneum to the nearest skin surface serves an important aid for diagnosis. The criteria used for an increased heel pad thickness includes: For a 150-pound subject, the heel-pad thickness should not exceed 22 mm and for every 25 pounds add 1mm to the cut-off limit.

Once the diagnosis is confirmed by laboratory results and MRI examination, surgical resection is the primary modality of treatment. Somatisation analogues can be used for preoperative shrinkage of the tumor. The morbidity and mortality is attributed to cardiorespiratory and cerebrovascular disease.

Amar Udare, MD
Radiodiagnosis, Tata Memorial Hospital
Mumbai, India 

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