Kümmell's disease: pathophysiology, diagnosis, treatment and the role of nuclear medicine. Rationale according to our experience.

Kümmell's disease (KD) is a rare clinical entity and includes patients, who after a trivial trauma and an asymptomatic period, develop a progressive vertebral body collapse and a painful kyphosis. The main pathologic eliciting event still remains unclear. Vertebral body collapse can be the result of infection, malignant neoplasia or trauma. It may be difficult to distinguish among them, particularly in osteoporosis. To explain the time lag between initial trauma and vertebral collapse, the hypothesis of ischemic necrosis was suggested. Many authors considering KD as a case of mere vertebral osteonecrosis have wrongly reported cases of osteonecrosis without a spinal trauma, as KD. The fact that intravertebral vacuum cleft often coexists with vertebral osteonecrosis further added to confusion. Various imaging modalities including bone scan support the diagnosis of KD. It is described that bone single photon emission tomography (SPET) or SPET/computed tomography scintigraphy using dynamic and static, acquisition can identify the chronicity of the lesions.

Kümmell' s disease: A rare spine entity in a young adult.

Over 100 years ago, Dr Hermann Kümmell described a rare clinical entity in which patients, after a trivial trauma and an asymptomatic period, developed a progressive vertebral body collapse and a painful kyphosis. We present the case of a 31years old heavy labourer, fitting Kümmell's criteria. The patient referred to us in an incapacitated state, due to persistent back pain. Radiographic examination revealed a body collapse of L1 vertebra. The patient had no previous medical record, other than a prolonged history of transient back pain episodes, related to heavy-weight lifting. Last attack was 1 year before presentation. Through course of time, he had undergone several clinical and radiological evaluations, by different orthopaedists, on different occasions, including the last episode, with no major findings. After an extensive workup, a percutaneous kyphoplasty of the affected vertebra was performed and a biopsy was obtained. The histologic examination of the specimen revealed vertebral osteonecrosis. A triggering pattern of repetitive spinal loading in hyperflexion is, for the first time, being recognized. We conclude that Kümmell's disease, although a rare condition, should be considered in any patient with refractory back pain symptoms. In such patients, vigorous follow-up turns to be of the essence.

Erdheim-Chester disease: a rare syndrome with a characteristic bone scintigraphy pattern.

Erdheim-Chester disease is a rare noninherited, non-Langerhans' cell histiocytosis, with multiorgan involvement. The skeleton is frequently involved in as many as 70-80% of all cases. In nearly half of the cases, there is an involvement of other organs such as the cardiovascular system, lung, kidneys, brain, and orbits. Extra-skeletal involvement is correlated with increased morbidity and mortality. In recent years, the disease is being described with increasing frequency although fewer than 200 cases have been identified worldwide. Besides its rarity, the disease has a characteristic almost pathognomonic bone scan appearance, which in some cases facilitates diagnosis of the syndrome. Bone scans also contribute to the qualitative assessment of skeletal involvement.

Is mucociliary transport velocity related to symptoms in chronic rhinosinusitis patients?

Mucociliary transport velocity (MTV) measured by rhinoscintigraphy is considered a reliable measure of mucociliary clearance, one of the mechanisms that are distorted in chronic rhinosinusitis (CRS). The aim of this study was to investigate possible correlation of MTV with the severity of patients' symptoms. We have studied thirty-seven CRS patients who completed the 20-item sinonasal outcome test (SNOT-20) form, a reliable measure of health related quality of life and were also examined by rhinoscintigraphy with technetium-99m macroaggregated albumin. Our findings showed that the MTV of our patients ranged from nil to 4.17mm/min with a mean value of 1.74+/-1.055 mm/min. The SNOT-20 scores varied from 0.3 to 3.7 with a mean of 1.6+/-0.922. The correlation between SNOT-20 score and MTV was not statistically significant (Spearman's r=-0.191). In conclusion, although rhinoscintigraphy is widely accepted as a reliable test of mucociliary velocity and clearance, it did not correlate with subjective measures of the severity of CRS.

Comparison between 180 degrees and 360 degrees acquisition arcs with and without correction by CT-based attenuation maps in normal hearts at rest.

OBJECTIVE: To investigate the effect of acquisition arc (180 degrees or 360 degrees ) and attenuation correction (AC), in artifact occurrence and image uniformity of myocardial perfusion SPECT studies in normal hearts. METHODS: Twenty male and 44 female patients with primary hyperparathyroidism and low probability of resting perfusion abnormalities were analysed. Tc-sestamibi myocardial perfusion studies were performed at rest with a hybrid SPECT/CT system. An anthropomorphic phantom was also imaged. RESULTS: Without AC, a 360 degrees orbit resulted in significantly lower artifact rates compared to the standard 180 degrees in both gender groups. Differences persisted (P<0.001) even after adjusting reconstruction filter settings to compensate for disproportionate count statistics between the two arcs. However, gender-related variation was not considerably decreased and sub-diaphragmatic activity was augmented with a 360 degrees arc. After AC with either arc, substantially lower defect scores and minimal gender-related differences were obtained compared to the standard technique. A 360 degrees arc yielded lower defect rates and count variability than did the 180 degrees arc (P<0.05). These differences were small and were eliminated after weighting for dissimilar count statistics. Sub-diaphragmatic signal was amplified, particularly with 360 degrees ; severe bowel-myocardial activity overlap complicated image interpretation in 14% of cases with 360 degrees versus 8% with 180 degrees . In certain aspects, phantom imaging findings diverged from patient studies. CONCLUSION: Without AC there is significant disparity between 180 degrees and 360 degrees concerning artifact occurrence. After CT-based AC differences between arcs in defect rate and image uniformity seem less critical. However, 180 degrees is favoured by less intensification of intestinal activity.

Two cases of synovitis, acne, pustulosis, osteitis--SAPHO syndrome.

Synovitis, acne, pustulosis, osteitis (SAPHO) syndrome is rare with yet unknown prevalence. The difficulty in recognizing the syndrome is due to the very wide diversity of its signs and symptoms, the lack of skin manifestations in many cases and to confusion in medical terminology in describing this syndrome. In this paper, we present two cases with characteristic bone lesions in bone scan and in radiology images that are considered to be SAPHO syndrome. In the first case the characteristic bone single photon emission tomography scan findings in a patient with spine involvement supposed by bone biopsy but were not followed by characteristic skin manifestations. The point of interest of this case lies on the significant improvement of both symptoms and scintigraphic findings after treatment with biphosphonates. In the second case the diagnosis was also based on the characteristic bone scan findings, although the patient referred to us for staging of prostate cancer. Detailed history and clinical examination revealed skin manifestations of the syndrome.