Periodontoid calcium pyrophosphate dihydrate deposition disease: “pseudogout” mass lesions of the craniocervical junction

Abstract

Between 1984 and 1996, seven patients with symptomatic masses located posterior to the odontoid process and containing calcium pyrophosphate dihydrate crystals were evaluated by the senior author (A.H.M). All patients presented with distal paresthesias and myelopathy and underwent transoral-transpharyngeal resection of the anterior arch of C-I, the odontoid process, and the compressing mass. Histological examination revealed the characteristic changes of calcium pyrophosphate dihydrate (CPPD) deposition disease, with nodular deposits of birefringent rhomboid crystals. On magnetic resonance imaging, the masses appeared predominantly isointense with neural tissue on T1-weighted images and iso-to hyperintense on T2-weighted images. On computerized tomography scans, small area of calcifications within the masses were apparent in all cases. All patients improved postoperatively, with six of seven patients requiring posterior fixation for instability as a second procedure. Calcium pyrophosphate dihydrate deposition causing periodontoid mass lesions is a distinct clinical disease entity that probably is underdiagnosed. In the authors' l opinion, the diagnosis can often be established preoperatively by the distinctive neuroradiological appearance of the masses. Therefore, CPPD deposition disease should be considered in the differential diagnosis of masses of the craniocervical junction, because it is amenable to early surgical intervention. The consulting neuropathologist should be made aware of this diagnostic possibility at the time of surgery.

Pseudogout Showing Meningoencephalitic Symptoms: Crowned Dens Syndrome

“…In those cases which did not recover, the patients underwent transoral-transpharyngeal resection of the anterior arch of C-1, the odontoid process and the compressing mass (6). In the present case, however, medication of NSAID(Lornoxicam) was found to be insufficient to reduce the abnormalities.…”

“…It is not fully clear why the depositions of these crystals cause a variety of different manifestations. Nevertheless, it seems reasonable to assume that HA and CPPD crystal depositions in joints and bursa disrupt the anatomical confines of the respective joint and then form masses in the periarticular tissue (6).…”

The crowned dens syndrome as a cause of neck pain: Report of two new cases and review of the literature

“…There are several reports of compressive cervical myelopathy caused most commonly by CPPD deposition of the ligamentum flavum (10,18 -20). Additionally, several groups have reported case series of CPPD crystal deposition of the periodontoid region, most commonly of the transverse ligament of the atlas (17,(21)(22)(23)(24)(25)(26)(27). Periodontoid CPPD crystal deposition was demonstrated by Dirheimer et al (22) in a study in which 27 neurologically asymptomatic patients with articular chondrocalcinosis were imaged by cranial-cervical junction X-ray polytomography.…”

Primary amyloidoma of the axis and acute spinal cord compression: a case report

“…Calcified tissue surrounding the odontoid process (crowned dens) indicates pyrophosphate dehydrated deposition (PPDD) disease [29], whereas inflammatory mass intensively enhanced by gadolinium injection is suggestive of rheumatoid arthritis (pannus) [20]. Spinal location of tophaceous gout is rare and appears dense on a CT scan [10].…”