Ossification of Posterior Longitudinal Ligament (OPLL)

 

Above lateral cervical radiograph and the T2, T1 weighted MR images show thickening and ossification of the Posterior Longitudinal Ligament (OPLL) posterior to C2 and C3 vertebral bodies. The PLL ossification would be seen as hypointense signal intense thickening of the PLL in both T1 and T2 images. Narrowing of the spinal canal with compression of the thecal sac and the cord is present at C2/C3 levels.

Sclerotic Skeletal Secondaries

T1 and T2 hypointense multiple lesions are noted in the dorsolumbar and sacral vertebrae, in the above MR images. These lesions are  hyperintense in STIR images. T1 and T2 hypointense signal intensity is suspicious for sclerotic nature of the lesions. Mild expansion of L3 vertebral body is also noted. No associated paraspinal soft tissue components were seen. Contrast MRI taken showed moderate enhancement in all lesions (not shown). 

Few similar signal intensity lesions are also seen in C6, D1 and D6 vertebral bodies.

CT images are confirmatory. L3 vertebral body lesion is extending to involve both pedicles and extending further into the posterior elements.

The most common cause for sclerotic bone metastases are prostate carcinoma in males and breast carcinoma in females. Occasionally transitional cell carcinoma of urinary bladder, gastric carcinoma, colonic carcinoma, neuroblastoma, testicular carcinoma and lymphoma can produce sclerotic metastasis. Carcinoid tumor of lung also usually result in sclerotic metastatic lesions.

Reference:

Chapman, 6th edition. 

Straight back syndrome

The whole spine T2 sagittal image shows straightening of the normal kyphotic angulation of the dorsal spine. Reduced antero-posterior dimension of the thorax is also noted. Features are favoring Straight Back Syndrome. (The patient had come for symptoms of low backache with radiation to right leg). 

The above image shows T2 weighted MRI of the dorsal spine. Image on the left shows a yellow line drawn along the anterior surface of D4 to D12 vertebral bodies. In straight back syndrome the distance between the yellow line and anterior surface of midportion of the D8 vertebral body should be < 1.2 cm. (This is the Davies modification (1980) of the DeLeon (1956) criteria, and is actually mentioned in the lateral chest x-ray, and not in MRI). In the above image this distance measured only ~2mm. 

The right side images shows AP dimension of thorax from the posterior surface of the sternum to the anterior surface of the D8 vertebral body, which should be < 10-11 cm. Here it measured exactly 10 cm.

Straight back syndrome is considered as a benign skeletal abnormality of the thorax, narrowed AP dimension of the thoracic cavity, resulting in cardiovascular and bronchial compression, but with most of the patients being asymptomatic. If symptomatic, patients usually present with symptoms of chest pain and palpitations, mimicking a primary cardiac condition. An ejection systolic murmur may be heard in the pulmonary area on auscultation. 

Mitral Valve prolapse (MVP) may be seen as an association in up to two third of patients. Prominence of the pulmonary arteries, deviation of the heart to left and cardiomegaly are also described in association.

References: 

1. Davies, M. K., Mackintosh, P., Cayton, R. M., Page, A. J., Shiu, M. F., & Littler, W. A. (1980). The straight back syndrome. The Quarterly journal of medicine, 49(196), 443–460.

2. Gold PM, Albright B, Anani S, Toner H. Straight Back Syndrome: positive response to spinal manipulation and adjunctive therapy - A case report. J Can Chiropr Assoc. 2013;57(2):143-149.

Solitary metastatic lesion of the spine

 70Y old female patient present with low back ache. MRI of the lumbo-sacral spine was performed. 

The whole spine T2 sagittal image is showing an isolated lesion involving the S2 vertebra and superior part of the S3. Lesion is appearing slightly hyperintense in T2, iso to slightly hypointense in T1 and markedly hyperintense in STIR. It is expansile, causing anterior and posterior contour bulge of the involved vertebrae and also the destruction of anterior cortex. 

Lesion is shown in the axial T2 and STIR coronal images here. T2 Axial images is showing near total obliteration of the the sacral spinal canal at the level, with marked compression of the remaining nerve roots. 

Moderate enhancement of the lesion is present with associated restricted diffusion. Features are in favor of an aggressive lesion. Signal intensity is not consistent with chordoma or Giant Cell Tumor.

Biopsy of the lesion was performed, was found out to be metastatic lesion from adenocarcinoma.  

Diffuse Idiopathic Skeletal Hyperostosis (DISH)

 

DISH or Diffuse Idiopathic Skeletal Hyperostosis, aka Forestier disease, is a common disorder of unknown etiology, characterized by intermittent pain and stiffness in the involved spine segments. Spinal involvement of DISH characteristically produces flowing type ossifications in the anterolateral margins of the at least 4 contiguous vertebrae. This ossification can be of variable thickness, can measure up to 2cm. 

The above images shows prominent ossifications in relation to the anterior aspects of C3 to C7 levels, with C4 to C7 appearing continuous. This is also causing mass effect on the hypopharyngeal soft tissue / pharyngo-esophageal junction.