technetium-tc-99m-medronate and Pseudomonas-Infections

Early diagnosis of necrotizing external otitis (NEO) includes the use of bone scintigraphy since clinical assessment alone cannot differentiate the necrotizing type of otitis from the severe type of external otitis in which there is no extension to the adjacent bone. Four-hour planar bone scintigraphy may reflect soft-tissue infection, and therefore may not be useful in distinguishing NEO from severe external otitis (SEO). Twenty-four-hour bone scintigraphy using planar or SPECT imaging may better reflect bone uptake and increase the accuracy of the test.. Twenty-six diabetic patients (12 diagnosed NEO; 14 SEO) and 10 nondiabetic (ND) patients were studied. Lesion-to-nonlesion (L/N) count ratios obtained from planar and SPECT imaging at 4 hr, 24 hr and 24 hr/4 hr (24/4) were assessed.. Count ratios obtained from the 4- and 24-hr planar and SPECT images were significantly higher in the NEO patients compared to SEO patients for both planar and SPECT studies (p < 0.001, 0.005). The 24/4 count ratio was also significantly higher in the NEO patients on the planar (p < 0.01) and the SPECT studies (p < 0.001). The ND patients were not different from SEO patients on 4-hr planar, 4- and 24-hr SPECT as well as 24/4-hr planar and SPECT studies. The L/N count ratio threshold yielding the best sensitivity for detecting NEO was 1.05 for the 24/4 SPECT study.. In diabetic patients, an early distinction between NEO and SEO patients can be reliably made by using L/N count ratios on 24/4 or 24-hr SPECT bone scintigraphy.

Topics: Diabetes Complications; Diagnosis, Differential; Female; Humans; Male; Middle Aged; Osteomyelitis; Otitis Externa; Prospective Studies; Pseudomonas Infections; Sensitivity and Specificity; Technetium Tc 99m Medronate; Temporal Bone; Tomography, Emission-Computed, Single-Photon

Qualitative technetium Tc 99m bone scintigraphy using phosphate compounds and gallium 67 scintigraphy were described as a helpful means in diagnosing necrotizing external otitis (NEO). They were, however, claimed to be nonspecific. Quantitative Tc 99m methylene diphosphonate bone scintigraphy and gallium 67 scintigraphy were performed in eight patients with NEO and in 20 patients with severe external otitis, in order to prove usefulness of scintigraphy in the diagnosis of NEO. Ratios of lesion to nonlesion for bone scintigraphy were 1.67 +/- 0.16 in patients with NEO and 1.08 +/- 0.09 in patients with severe external otitis, and for gallium 67 scintigraphy they were 1.35 +/- 0.24 in NEO patients and 1.05 +/- 0.03 in patients with severe external otitis. There was no difference in uptake between diabetic patients with severe external otitis and nondiabetic patients. The scintigraphic studies were also evaluated using a qualitative scoring method (scores 0 to +4), according to the intensity of the radiopharmaceutical uptake. This method was found to be inferior in the diagnosis of NEO compared with the quantitative method. We conclude that lesion-to-nonlesion ratios greater than 1.5 and 1.3 on bone and gallium 67 scintigraphy, respectively, are indicative of NEO. Quantitative bone scintigraphy, which is quicker to perform, may be used as a single imaging modality for the diagnosis of NEO.

Topics: Adult; Aged; Aged, 80 and over; Aminoglycosides; Anti-Bacterial Agents; Diabetes Mellitus; Diagnosis, Differential; Female; Gallium Radioisotopes; Granulation Tissue; Humans; Male; Middle Aged; Necrosis; Observer Variation; Otitis Externa; Prospective Studies; Pseudomonas Infections; Radionuclide Imaging; Sensitivity and Specificity; Technetium Tc 99m Medronate; Temporal Bone

Topics: Diabetes Mellitus, Type 1; Gallium Radioisotopes; Humans; Male; Middle Aged; Osteomyelitis; Otitis Externa; Pseudomonas Infections; Skull; Technetium Tc 99m Medronate; Tomography, Emission-Computed

Pseudomonas otitis externa in elderly diabetics may extend aggressively to adjacent bone, cranial nerves, meninges, and vessels, leading to a clinical diagnosis of "malignant" external otitis. Early diagnosis is necessary for successful treatment. This study compares the findings of initial radiographs, thin-section tomography of temporal bone, CT scans of head and neck, technetium-99m methylene diphosphonate (MDP) and gallium-67 citrate scintigraphy, and single-photon emission computed tomography (SPECT) for detection of temporal bone osteomyelitis in ten patients fulfilling the clinical diagnostic criteria of malignant external otitis. Skull radiographs were negative in all of the eight patients studied. Thin-section tomography was positive in one of the seven patients studied using this modality. CT scanning suggested osteomyelitis in three of nine patients. Both Tc-99m and Ga-67 citrate scintigraphy were positive in 10 of 10 patients. Three patients who were considered to be in clinical remission had positive Tc-99m scans and normal Ga-67 scans. These results suggest that technetium and gallium scintigraphy are more sensitive than radiographs and CT scans for early detection of malignant external otitis. Gallium scintigraphy appears to be more specific for follow-up evaluation of these patients.

Topics: Adult; Aged; Diphosphonates; Female; Gallium Radioisotopes; Humans; Male; Middle Aged; Otitis Externa; Pseudomonas Infections; Technetium; Technetium Tc 99m Medronate; Temporal Bone; Tomography, Emission-Computed; Tomography, X-Ray Computed

Topics: Adolescent; Diphosphonates; Female; Gallium Radioisotopes; Humans; Osteomyelitis; Pseudomonas Infections; Radionuclide Imaging; Sacroiliac Joint; Technetium; Technetium Tc 99m Medronate

The usefulness of radionuclear scanning in the treatment of 18 patients with necrotizing progressive "malignant" external otitis is discussed. A Tc 99-m bone scan, a valuable test since results are positive in early cases of osteomyelitis of the temporal bone and base of skull, showed increased uptake in all 18 patients. In 6 patients, Ga-67 citrate scans were obtained at the start of therapy and at 5-6 week intervals thereafter. The serial gallium scans were useful in evaluating the effectiveness of therapy since the uptake decrease with control of infection.

Topics: Aged; Diabetes Complications; Diphosphonates; Female; Gallium Radioisotopes; Humans; Male; Middle Aged; Necrosis; Osteomyelitis; Otitis Externa; Pseudomonas Infections; Radionuclide Imaging; Skull; Technetium; Technetium Tc 99m Medronate; Temporal Bone

Since Chandler's initial report in 1968 on "malignant external otitis" (MEO), this entity has been recognized in its earlier stages with increasing frequency. As a result of this, the availability of new antimicrobial agents, and the judicious use of surgery, there has been an improvement in the results of therapy. There remains, however, a subgroup of patients who continue to experience a significant mortality from this infection. A review and selected discussion of our experience with MEO from 1976 to 1979 is presented. Six patients have been diagnosed and successfully treated for MEO. They presented with problems ranging from severe otalgia to multiple cranial neuropathy. For the most part, therapy consisted of the now standard aminoglycoside and carbenicillin combination. Two of the patients were in the high mortality risk group. One of these patients developed an osteomyelitis which extended across the skull base resulting in bilateral cranial neuropathies. His therapy included surgery as well as long-term (months) outpatient treatment with tobramycin and carbenicillin with an excellent result. The second patient was treated similarly. The efficacy of this approach is discussed as well as the usefulness of radionuclide bone scanning in assessing the course and therapy of patients with MEO.

Topics: Aged; Anti-Bacterial Agents; Cranial Nerve Diseases; Diphosphonates; Drug Therapy, Combination; Follow-Up Studies; Humans; Male; Middle Aged; Otitis Externa; Pseudomonas aeruginosa; Pseudomonas Infections; Radionuclide Imaging; Skull; Technetium; Technetium Tc 99m Medronate