Atlantoaxial Subluxation

Twenty-nine patients with atlantoaxial subluxation (18 with rheumatoid arthritis, 2 due to trauma, 4 with os odontoideum, and one each with polyarteritis nodosa, rheumatic fever, Klippel-Feil syndrome, achondroplasia, and cause unknown) were evaluated using a 0.22 tesla resistive MRI unit. Cord compression was classified into four grades according to the degree on magnetic resonance imaging. There were 7 patients with no thecal sac compression (grade 0), 10 with a minimal degree of subarachnoid space compression without cord compression (grade 1), 7 with mild cord compression (grade 2), and 5 with severe cord compression or cord atrophy (grade 3). Although the severity of myelopathy showed poor correlation with the atlantodental interval on conventional radiography, high correlation was observed between MR grading and the degree of myelopathy. The high signal intensity foci were observed in 7 of 12 patients with cord compression (grades 2 and 3) on T2 weighted images. Other frequently observed findings in rheumatoid arthritis included soft tissue masses of low to intermediate signal intensity in the paraodontoid space, erosions of the odontoid processes, and atlantoaxial impaction on T1 and T2 weighted images.

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Retro-Odontoid Pseudotumor Associated with Rheumatoid Arthritis

Austin Journal of Radiology ◽

10.26420/austinjradiol.2021.1144 ◽

2021 ◽

Vol 8 (6) ◽

Author(s):

Hajar A ◽

◽

Laila J ◽

Laamrani FZ ◽

◽

...

Keyword(s):

Rheumatoid Arthritis ◽

Signal Intensity ◽

Soft Tissue Mass ◽

Bone Erosion ◽

Imaging Modality ◽

Odontoid Process ◽

Cord Compression ◽

Tissue Mass ◽

Intermediate Signal Intensity ◽

T2 Weighted Images

Retro-Odontoid Pseudotumor (ROP) commonly labeled as “pannus” is a non-neoplastic soft tissue mass adjacent to the odontoid process of C2 that is frequently associated with rheumatoid arthritis. It is due to inflammation and thickening of the synovium surrounding the dens and may lead to ligament laxity, and bone erosion resulting in C1-C2 joint laxity and subluxation with possible spinal cord compression. MRI is the imaging modality of choice to assess ROP and evaluate its extent. Three patterns of ROP are described following histological features; distinguish inflammatory hyper vascular pannus (hyperintense on T2-weighted images and enhancing) (Figure 1 and 2), combined pannus (intermediate signal intensity on T2- weighted images and intermediately enhancing), and fibrous pannus (low signal intensity on all sequences and non-enhancing).

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Unusual Presentation of Popliteal Cyst on Magnetic Resonance Imaging

Case Reports in Orthopedics ◽

10.1155/2016/1214030 ◽

2016 ◽

Vol 2016 ◽

pp. 1-4 ◽

Cited By ~ 1

Author(s):

Tsuyoshi Ohishi ◽

Masaaki Takahashi ◽

Daisuke Suzuki ◽

Yukihiro Matsuyama

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Signal Intensity ◽

Final Diagnosis ◽

Magnetic Resonance Images ◽

Popliteal Cyst ◽

High Signal ◽

Resonance Imaging ◽

Intermediate Signal Intensity ◽

T2 Weighted Images

Popliteal cyst commonly presents as an ellipsoid mass with uniform low signal intensity on T1-weighted magnetic resonance images and high signal intensity on T2-weighted images. Here, we describe a popliteal cyst with unusual appearance on magnetic resonance imaging, including heterogeneous intermediate signal intensity on T2-weighted images. Arthroscopic cyst decompression revealed that the cyst was filled with necrotic synovial villi, indicative of rheumatoid arthritis. Arthroscopic enlargement of unidirectional valvular slits with synovectomy was useful for the final diagnosis and treatment.

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Case 13.6

Mayo Clinic Body MRI Case Review ◽

10.1093/med/9780199915705.003.0330 ◽

2014 ◽

pp. 625-625

Author(s):

Christine U. Lee ◽

James F. Glockner

Keyword(s):

Chest Wall ◽

Signal Intensity ◽

High Signal Intensity ◽

High Signal ◽

Multiple Regions ◽

Lateral Chest ◽

Wall Mass ◽

Chest Wall Mass ◽

T2 Weighted Images

3-year-old girl with a chest wall mass that her mother noticed Axial (Figure 13.6.1) and coronal (Figure 13.6.2) FSE T2-weighted images demonstrate a large heterogeneous mass that has multiple regions of high signal intensity and occupies much of the left hemothorax. Note involvement of the lateral chest wall and a lower rib best seen on the coronal images....

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Case 11.16

Mayo Clinic Body MRI Case Review ◽

10.1093/med/9780199915705.003.0294 ◽

2014 ◽

pp. 556-556

Author(s):

Christine U. Lee ◽

James F. Glockner

Keyword(s):

Signal Intensity ◽

Pelvic Mass ◽

Intermediate Signal Intensity ◽

Heterogeneous Enhancement ◽

T2 Weighted Images

57-year-old woman with a pelvic mass Axial fat-suppressed FSE T2-weighted images (Figure 11.16.1) demonstrate a large heterogeneous mass in the central and right pelvis with regions of high and intermediate signal intensity. Axial postgadolinium 3D SPGR images (Figure 11.16.2) reveal heterogeneous enhancement of the lesion with anterior and inferior cystic or necrotic regions....

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Case 4.5

Mayo Clinic Body MRI Case Review ◽

10.1093/med/9780199915705.003.0103 ◽

2014 ◽

pp. 196-196

Author(s):

Christine U. Lee ◽

James F. Glockner

Keyword(s):

Prostate Cancer ◽

Contrast Agent ◽

Signal Intensity ◽

Pancreatic Mass ◽

Pancreatic Tail ◽

Intermediate Signal Intensity ◽

History Of ◽

T2 Weighted Images

58-year-old man with a history of prostate cancer and a possible pancreatic mass on CT Axial fat-suppressed FSE T2-weighted images obtained before (Figure 4.5.1) and after (Figure 4.5.2) administration of an SPIO contrast agent demonstrate an ovoid mass in the pancreatic tail with intermediate signal intensity that becomes significantly hypointense after SPIO administration and matches the signal intensity of the spleen....

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Atlantoaxial stabilization in rheumatoid arthritis

Journal of Neurosurgery ◽

10.3171/jns.1991.74.1.0001 ◽

1991 ◽

Vol 74 (1) ◽

pp. 1-7 ◽

Cited By ~ 48

Author(s):

Stephen M. Papadopoulos ◽

Curtis A. Dickman ◽

Volker K. H. Sonntag

Keyword(s):

Rheumatoid Arthritis ◽

Spinal Cord ◽

Spinal Cord Compression ◽

Cord Compression ◽

Atlantoaxial Subluxation ◽

High Rate ◽

Content Type ◽

Operative Stabilization ◽

Asymptomatic Patients ◽

Fine Print

✓ Atlantoaxial subluxation in patients with rheumatoid arthritis is common. Operative stabilization is clearly indicated when signs and symptoms of spinal cord compression occur. However, many recommend early operative fusion before evidence of appreciable neural compression occurs because 1) the myelopathy in these patients may be irreversible; 2) the overall prognosis is poor once symptoms of cord compression are present; and 3) the risk of sudden death associated with atlantoaxial subluxation is increased even in asymptomatic patients. The authors believe that rheumatoid arthritis patients in relatively good health without advanced multisystem disease and less than 65 years of age should be considered for operative stabilization if mobile atlantoaxial subluxation is greater than 6 mm. Seventeen patients with severe rheumatoid arthritis and atlantoaxial subluxation treated with a posterior arthrodesis are presented. A new method of fusion, devised by the senior author (V.K.H.S.), was utilized in all cases. Indications for operative therapy in these patients included evidence of spinal cord compression in 11 patients (65%) and mobile atlantoaxial subluxation greater than 6 mm but no signs or symptoms of cord compression in six patients (35%). Thirteen patients developed a stable osseous fusion, two patients a well-aligned fibrous union, one patient a malaligned fibrous union, and one patient died prior to evaluation of fusion stability. The details of the operative technique and management strategies are presented. Several technical advantages of this method of fusion make this approach particularly useful in patients with rheumatoid arthritis. Because of multisystem involvement of this disease, a high rate of osseous fusion is often difficult to achieve.

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Frontoethmoidal Mucoceles: CT and MRI Evaluation

The Neuroradiology Journal ◽

10.1177/197140090702000519 ◽

2007 ◽

Vol 20 (5) ◽

pp. 586-596 ◽

Cited By ~ 5

Author(s):

I. Tsitouridis ◽

M. Michaelides ◽

A. Bintoudi ◽

V. Kyriakou

Keyword(s):

Signal Intensity ◽

Treatment Plan ◽

Correct Diagnosis ◽

Brain Parenchyma ◽

High Signal ◽

Intermediate Signal Intensity ◽

Multiplanar Imaging ◽

Previous Trauma ◽

Peripheral Enhancement ◽

Ct And Mri

Paranasal sinus mucocele is an expanded, airless, mucus-filled sinus caused by obstruction of the sinus ostium. It is a benign slow growing epithelial lined lesion, bulging against adjacent anatomical structures, without infiltrating them. The purpose of our study is to describe the CT and MR findings in 19 patients (ten women, nine men, 18–72 years, mean age: 48.1) with surgically confirmed frontoethmoidal mucoceles between 1999–2005. CT scans displayed mucoceles as non enhancing soft tissue density lesions, generally isodense to the brain parenchyma, expanding the sinuses in most cases, eroding adjacent bones and extending intraorbitally or intracranially. Signal intensity in T2WI and T1WI MR images varied, but generally lesions had high signal intensity in T2WI and low to intermediate signal intensity in T1WI. Some of the lesions demonstrated regular linear peripheral enhancement after administration of contrast medium. The causes of mucoceles included mucosal thickening from chronic sinusitis, adhesions from previous operation in the nasal cavity, previous trauma, small nasal polyps and a small osteoma, while in six patients (31.5%) the cause of the mucocele remained unrecognized even after surgery. No underlying malignant tumor was found in any of the cases as the cause of obstruction. CT and MRI established the correct diagnosis in all patients. CT was more sensitive in determining bone erosions, while MRI had the advantage of multiplanar imaging and was much more sensitive for differentiating mucocele from a tumor on the basis of MR signal intensity characteristics. In conclusion, CT and MRI are the methods of choice for diagnosing mucoceles of the paranasal sinuses and are of major importance for the treatment plan. Each method seems to have its own advantages and should be used as complementary investigations of sinonasal pathology. Enhanced CT scan should only be performed in the absence or contraindication for enhanced MR imaging.

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MR Findings of Ejaculatory Duct Cysts

Acta Radiologica ◽

10.1177/028418519403500513 ◽

1994 ◽

Vol 35 (5) ◽

pp. 459-462 ◽

Cited By ~ 3

Author(s):

Y. Robert ◽

J.-M. Rigot ◽

N. Rocourt ◽

L. Lemaitre ◽

J. Biserte ◽

...

Keyword(s):

Mr Imaging ◽

Signal Intensity ◽

Ejaculatory Duct ◽

High Signal Intensity ◽

Cyst Fluid ◽

High Signal ◽

Rare Type ◽

T1 And T2 ◽

Prostatic Gland ◽

T2 Weighted Images

Ejaculatory duct cysts are a rare type of prostatic cysts. We report 3 cases of symptomatic ejaculatory duct cysts which have been explored by MR imaging. The MR findings were round or oval masses, medial or paramedial in the prostatic gland above the level of the verumontanum, extending into the prostatic base. They displayed a low signal intensity on T1-weighted images and high signal intensity on T2-weighted images (2 cases) or high signal intensity on both T1- and T2-weighted images (1 case). The diagnosis was confirmed by an ultrasonographically guided transperineal aspiration demonstrating spermatozoa in the cyst fluid.

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Polyorquidism: case report comparing ultrasonography and magnetic resonance imaging

Revista Brasileira de Saúde Materno Infantil ◽

10.1590/1806-93042020000300013 ◽

2020 ◽

Vol 20 (3) ◽

pp. 899-903

Author(s):

Lucas Ribeiro dos Santos ◽

Márcio Luís Duarte ◽

Élcio Roberto Duarte ◽

Felipe Nunes Figueiras

Keyword(s):

Magnetic Resonance Imaging ◽

Case Report ◽

Magnetic Resonance ◽

Signal Intensity ◽

World Literature ◽

High Signal ◽

Resonance Imaging ◽

Intermediate Signal Intensity ◽

Imaging Characteristics ◽

Initial Clinical Evaluation

Abstract Introduction: polyorchidism is an unusual pathology, about 200 cases in the world literature. Case report: we reported a case of polyorchidism in a 16-year-old male patient diagnosed by ultrasound and confirmed by magnetic resonance imaging. Discussion: most of the cases presented, there is a supernumerary testis, but there are reports on more than three, up to five testicles with supranumerical gonads on both sides of the scrotum. The diagnosis is usually performed in late puberty, incidentally, with a painless scrotal mass or at the emergency room, presenting a testicular torsion of the whole hemiscrotum or supernumerary testisalone, and the differential diagnosis should be made with epididymal cyst and spermatocele, besides other extra-testicular masses (hydroceles, varicoceles, lipomas, tumors.) and para-testicular masses (hernias, scrotal calculi). After the initial clinical evaluation, ultrasound is the first line subsidiary exam. Magnetic Resonance Imaging is very helpful, just in case the ultrasound diagnosis is uncertain. The supernumerary testishave the same Magnetic Resonance Imaging characteristics as the normal testes (intermediate signal intensity on T1- weighted images and high signal intensity on T2-weighted images).

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