Bone SPECT in management of mandibular condyle hyperplasia. Report of a case and review of literature.

In the present paper we report the case of a 14-year-old girl suffering from condylar hyperplasia and enlargement of ipsilateral jaw body, stressing the importance of bone SPECT in the clinical management of this temporomandibular joint (TMJ) disorder. Condylar hyperplasia is an uncommon idiopathic monolateral disorder of jaw growth consistent with exuberant or persistent activity of the condyle nucleus finally involving sociopsychological aspects due to facial dysmorphism. Besides facial asymmetry our patient showed prognathism, malocclusion, worsening otalgia and headache. Conventional X-rays examinations and multislice spiral CT gave us important morphostructural information also thanks to 3D volume-rendered and virtual reconstructions, while bone SPECT by detecting an intense well focused (99m)Tc-MDP uptake allowed to achieve uninvasively the final diagnosis of primary condyle hyperplasia. In spite of the full imaging characterization of TMJ disorders, consensus on best timing and therapeutic approaches on condylar hyperplasia is yet to be reached. In the present case patient was first treated orthodontically, planning a "high" condylectomy intervention after at least 6 months.

[Radionuclide imaging in oral implantations. Personal experience in maxillary sinus elevation]. / La diagnostica per immagini con radionuclidi nell'implantologia orale. Esperienza personale negli interventi di sollevamento del pavimento del seno mascellare.

PURPOSE: Presently nuclear medicine techniques are not very popular in oral implantology, but they can play an interesting role in this surgical field too. In particular bone scan with 99mTc-MDP allows to evaluate the function of oral implants and the survival of bone grafts. We report our experience with skull bone scan in maxillary sinus lifting. MATERIAL AND METHODS: We performed a three-year follow-up on 13 patients treated with inlay-one stage uni- or bilateral sinus lifting with a mixture composed of 90% bovine bone powder and of 10% small bone splinters and autogenous fibrin glue. We performed imaging studies and quantitated implant MDP uptake from the mean values at the surgical site to the 5th neck vertebral ratio (M/V index). The M/V index was also statistically compared with the one measured in 13 patients with severe resorption of distal upper dental arches (bone height less than 0.5 cm) and in 63 patients with normal dental status. Scintigraphic data were interpreted in the light of clinical, radiological and histologic findings. RESULTS: All oral implants appeared to be fixed and radiographs showed good positioning and bone adhesion; bone height exceeded 1 cm. Peri implant biopsy material was formed by normal mature bone tissue without bovine bone granules, necrotic areas and inflammatory cells. The highest bone activity (M/V index: 1.54-2.57) was observed 1-4 months after sinus lifting. Then MDP uptake decreases and 18 months after surgery radionuclide uptake in maxillary arches is homogeneous, with M/V values of 0.81-0.88. The average M/V value in the 18 surgical sites was clearly higher than in the resorbed (1.44 vs 0.64; Kruskall-Wallis ANOVA test; Dunn's method; p < 0.05) and normal (1.44 vs 0.73; p < 0.05) maxillary arches. DISCUSSION AND CONCLUSIONS: 99mTc-MDP can show the transformation of newformed into mature bone and then allows in vivo visualization of implant osteointegration. The importance of our work lies in the use of radionuclide imaging to assess both the function of oral implants inserted by a complex surgical technique and the expected bioactive properties of the filling mixture. Nevertheless the strong active autogenous compounds do not permit to detect the real agent of local bone induction. An interesting finding is that implant stability is biologically gained 18 months after intervention and that the uptake index facilitates comparison of sequential scans and confirmation of local bone growth. Therefore high MDP uptake by the implant 2-3 years after surgery can suggest mechanical or septic bone injury which can lead to implant failure if not treated promptly. In conclusion we believe that quantitative bone scan is a valid diagnostic tool in the follow-up of oral implants inserted with sinus lifting, though our experience needs confirmation on larger series and new research is warranted to understand the real mechanisms of assisted bone regeneration.

Comparison of the cost-effectiveness of three approaches to screening for and treating sight-threatening diabetic retinopathy.

The purpose of this study was to analyse and compare the costs involved in screening for and treating sight-threatening diabetic retinopathy in three different clinical settings. In the first setting, diabetologists screened using ophthalmoscopy and color photography, according to the St. Vincent Declaration guidelines, and selected patients for further assessment by a visiting ophthalmologist and for treatment in another hospital. In the second setting, all patients were regularly referred to ophthalmologists, either in the same hospital or elsewhere, for all aspects of eye care. In the third setting, screening was done again with ophthalmoscopy alone by diabetologists who followed the St. Vincent Declaration guidelines; however, further assessment and treatment were carried out in the eye department of the same hospital. Costs to the Italian National Health Service and to patients were calculated per screening performed and per patient subjected to laser treatment as a result of screening. A sensitivity analysis was then performed to simulate the costs of standardised patient populations going through the three different settings. It is concluded that absolute costs would be lower, both for the Italian National Health Service and for patients, if screening, assessment and treatment were all carried out in the same hospital. Equipping a diabetic clinic specially for screening would not be more expensive than delegating eye care to external parties, even for a hospital without an eye department. Moreover, delegating eye care more than doubles costs for patients. Screening for, assessing and treating sight-threatening diabetic retinopathy may be a cost-effective procedure for society as a whole in Italy.