Tamotsu Kamishima

Donor Site Evaluation after Autologous Osteochondral Mosaicplasty for Cartilaginous Lesions of the Elbow Joint

Background One significant disadvantage of autologous osteochondral mosaicplasty (mosaicplasty) is the harvesting of osteochondral grafts from the normal articular area of the knee joint. However, the effect of harvesting grafts on knee function remains unclear. Purpose To clarify the functional effects on the donor knee of harvesting osteochondral grafts and to perform magnetic resonance imaging evaluation of donor site repair after mosaicplasty for capitellar osteochondritis dissecans in young athletes. Study Design Case series; Level of evidence, 4. Methods Eleven male competitive athletes with advanced lesions of capitellar osteochondritis dissecans underwent mosaicplasties. The surgical technique involves obtaining small-sized cylindrical osteochondral grafts from the lateral periphery of the femoral condyle at the level of the patellofemoral joint and transplanting them to osteochondral defects in the capitellum. Assessment at a mean follow-up of 26 months included local findings of the donor knees, a Lysholm knee scoring scale, International Knee Documentation Committee standard evaluation form, and magnetic resonance imaging evaluation. Results All patients returned to a competitive level of their previous sports without any donor site disturbances. Based on the Lysholm knee score and International Knee Documentation Committee evaluation form, all knees were graded as excellent and normal, respectively. The magnetic resonance imaging showed 50% to 100% defect fill in 6 of 9 patients and normal or nearly normal signals in 4 patients at the donor sites. Conclusion No adverse effects of osteochondral graft harvest on donor knee function were found after mosaicplasty for capitellar osteochondritis dissecans in young athletes. However, magnetic resonance imaging indicates that the donor site is resurfaced with fibrous tissue.

Change of synovial vascularity in a single finger joint assessed by power doppler sonography correlated with radiographic change in rheumatoid arthritis: comparative study of a novel quantitative score with a semiquantitative score.

To investigate the relationship between synovial vascularity assessed by quantitative power Doppler sonography (PDS) and progression of structural bone damage in a single finger joint in patients with rheumatoid arthritis (RA).

Radiographic prognosis of finger joint damage predicted by early alteration in synovial vascularity in patients with rheumatoid arthritis: Potential utility of power doppler sonography in clinical practice.

To investigate the relationship between synovial vascularity and progression of structural bone damage in each finger joint in patients with rheumatoid arthritis (RA) and to demonstrate synovial vascularity as a potential therapeutic marker.

The incidence and mechanism of sunitinib-induced thyroid atrophy in patients with metastatic renal cell carcinoma.

Background:To elucidate the incidence and mechanisms of sunitinib-induced thyroid atrophy, we investigated serial volumetric and functional changes, and evaluated histological changes of the thyroid gland in metastatic renal cell carcinoma patients who received sunitinib.Methods:Thyroid volume (by computed tomography volumetry) and thyroid function were measured at baseline, during the treatment, and at post-treatment periods. Histological evaluation of the thyroid gland was performed in four autopsied patients.Results:The median reduction rate in thyroid volume at last evaluation during sunitinib treatment was 30% in all 17 patients. The incidence of hypothyroidism during sunitinib treatment was significantly higher in the high reduction rate group (n=8; more than 50% reduction in volume) than in the low reduction rate group (n=9; less than 50% reduction in volume). Half of the patients in the high reduction rate group exhibited a transient thyroid-stimulating hormone suppression, suggesting thyrotoxicosis during sunitinib treatment. Histological evaluation demonstrated atrophy of thyroid follicles and degeneration of follicular epithelial cells without critical diminution of vascular volume in the thyroid gland.Conclusion:Thyroid atrophy is frequently observed following sunitinib treatment and may be brought about by sunitinib-induced thyrotoxicosis or the direct effects of sunitinib that lead to degeneration of thyroid follicular cells.

Rapid estimation of split renal function in kidney donors using software developed for computed tomographic renal volumetry

PURPOSE To evaluate the speed and precision of split renal volume (SRV) measurement, which is the ratio of unilateral renal volume to bilateral renal volume, using a newly developed software for computed tomographic (CT) volumetry and to investigate the usefulness of SRV for the estimation of split renal function (SRF) in kidney donors. METHOD Both dynamic CT and renal scintigraphy in 28 adult potential living renal donors were the subjects of this study. We calculated SRV using the newly developed volumetric software built into a PACS viewer (n-SRV), and compared it with SRV calculated using a conventional workstation, ZIOSOFT (z-SRV). The correlation with split renal function (SRF) using (99m)Tc-DMSA scintigraphy was also investigated. RESULTS The time required for volumetry of bilateral kidneys with the newly developed software (16.7±3.9s) was significantly shorter than that of the workstation (102.6±38.9s, p<0.0001). The results of n-SRV (49.7±4.0%) were highly consistent with those of z-SRV (49.9±3.6%), with a mean discrepancy of 0.12±0.84%. The SRF also agreed well with the n-SRV, with a mean discrepancy of 0.25±1.65%. The dominant side determined by SRF and n-SRV showed agreement in 26 of 28 cases (92.9%). CONCLUSION The newly developed software for CT volumetry was more rapid than the conventional workstation volumetry and just as accurate, and was suggested to be useful for the estimation of SRF and thus the dominant side in kidney donors.

Splenic volume measurements on computed tomography utilizing automatically contouring software and its relationship with age, gender, and anthropometric parameters.

OBJECTIVE The present research was conducted to establish the normal splenic volume in adults using a novel and fast technique. The relationship between splenic volume and age, gender, and anthropometric parameters was also examined. MATERIALS AND METHODS The splenic volume was measured in 230 consecutive patients who underwent computed tomography (CT) scans for various indications. Patients with conditions that have known effect on the spleen size were not included in this study. A new technique using volumetric software to automatically contour the spleen in each CT slice and quickly calculate splenic volume was employed. Inter- and intra-observer variability were also examined. RESULTS The average splenic volume of all the subjects was 127.4+/-62.9 cm(3), ranging from 22 to 417 cm(3). The splenic volume (S) correlated with age (A) (r=-0.33, p<0.0001), body weight (W) (r=0.35, p<0.0001), body mass index (r=0.24, p<0.0001) and body surface area (BSA) (r=0.31, p<0.0001). The age-adjusted splenic volume index correlated with gender (p=0.0089). The formulae S=W[6.47A(-0.31)] and S=BSA[278A(-0.36)] were derived and can be used to estimate the splenic volume. Inter- and intra-observer variability were 6.4+/-9.8% and 2.8+/-3.5% respectively. CONCLUSION Of the anthropometric parameters, the splenic volume was most closely linked to body weight. The automatically contouring software as well as formulae can be used to obtain the volume of the spleen in regular practice.

Renal cortical volume measured using automatic contouring software for computed tomography and its relationship with BMI, age and renal function

PURPOSE To evaluate the relationship between renal cortical volume, measured by an automatic contouring software, with body mass index (BMI), age and renal function. MATERIALS AND METHODS The study was performed in accordance to the institutional guidelines at our hospital. Sixty-four patients (34 men, 30 women), aged 19 to 79 years had their CT scans for diagnosis or follow-up of hepatocellular carcinoma retrospectively examined by a computer workstation using a software that automatically contours the renal cortex and the renal parenchyma. Body mass index and estimated glomerular filtration rate (eGFR) were calculated based on data collected. Statistical analysis was done using the Student t-test, multiple regression analysis, and intraclass correlation coefficient (ICC). RESULTS The ICC for total renal and renal cortical volumes were 0.98 and 0.99, respectively. Renal volume measurements yielded a mean cortical volume of 105.8cm(3)±28.4SD, mean total volume of 153cm(3)±39SD and mean medullary volume of 47.8cm(3)±19.5SD. The correlation between body weight/height/BMI and both total renal and cortical volumes presented r=0.6, 0.6 and 0.4, respectively, p<0.05, while the correlation between renal cortex and age was r=-0.3, p<0.05. eGFR showed correlation with renal cortical volume r=0.6, p<0.05. CONCLUSION This study demonstrated that renal cortical volume had a moderate positive relationship with BMI, moderate negative relationship with age, and a strong positive relationship with the renal function, and provided a new method to routinely produce volumetric assessment of the kidney.

In Vivo Visualization of Vascular Patterns of Rotator Cuff Tears Using Contrast-Enhanced Ultrasound

Background Hypoxia and decreased blood supply have been proposed as risks for tendon rupture. Visualization of the vascularity of intact and torn rotator cuffs would be useful for improving treatments for rotator cuff tear. Purpose To assess vascularity inside a tendon or an adjacent rotator cuff insertion point in patients differing in age and extent of damage to the tendon. Study Design Cross-sectional study; Level of evidence, 3. Methods Ten volunteers (all men) and 15 patients (10 men, 5 women) consented to participate in the study. Contrast agent for enhanced ultrasound was injected intravenously. Enhanced ultrasound images of the torn cuff and the contralateral shoulder were recorded for 1 minute. Four small regions of interest, the articular and bursal sides of the tendon and the medial and lateral sides of the bursa, were studied in all shoulders. Results There was a significant decrease in blood flow in the intratendinous region in elderly subjects compared with young subjects, but age had no effect on blood flow in bursal tissue. Blood flow in ruptured rotator cuffs did not differ from that in intact rotator cuffs. The intraclass correlation coefficient for intraobserver reproducibility was 0.82 (95% confidence interval: 0.77-0.86). Conclusions The findings of this investigation were the hypovascular pattern in intratendinous tissue compared with the subacromial bursa, the age-related decrease in intratendinous vascularity, and the hypovascular pattern in the tendon, regardless of rupture of the tendon. Clarification of vascular patterns inside or around the torn ends of a rotator cuff will assist in the development of successful treatments for torn rotator cuffs.

Power Doppler ultrasound of rheumatoid synovitis: quantification of vascular signal and analysis of interobserver variability

ObjectiveThe objective of this study was to assess interobserver uncertainties in power Doppler (PD) examination of the fingers of patients with rheumatoid arthritis (RA), by separating the source of the discrepancy into (1) acquisition of the images and (2) criteria for assessment of the images.Materials and methodsTwenty patients who had been diagnosed with RA were enrolled in this study. Ultrasound examinations were performed by one inexperienced and two experienced sonographers. Interobserver variation was measured using a conventional semiquantitative image grading scale. Interobserver variation of the quantitative PD (QPD) index (the summation of the colored pixels in a region of interest) was also assessed.ResultsThe agreement was higher between the two experienced sonographers (kappa value of 0.8) than between experienced and inexperienced sonographers (kappa value, 0.6–0.7) in the semiquantitative image grading scale. Results suggest that the difference in the assessment on the image grading scale was due more to the difference in the acquisition of the images than to variations in the grading criteria between sonographers. An excellent relationship was noted between the image grading scale and the QPD index for Doppler signal with a Spearman’s coefficient of rank correlation of 0.83 (P < 0.0001).ConclusionsInterobserver discrepancies in the image grading and QPD index methods were due more to the difference in the acquisition of the image than to the grading criteria used. The QPD index seems to be as reliable as the image grading scale with reasonable interobserver agreement between experienced sonographers.

A Retrospective Evaluation of Magnetic Resonance Imaging Effectiveness on Capitellar Osteochondritis Dissecans Among Overhead Athletes

Background: Magnetic resonance imaging (MRI) has been widely used to characterize osteochondritis dissecans (OCD) lesions. However, the usefulness of MRI for predicting fragment stability in OCD of the humeral capitellum (capitellar OCD) remains unclear. Hypothesis: Preoperative MRI cannot accurately diagnose fragment instability of capitellar OCD in overhead athletes. Study Design: Cohort study (diagnosis); Level of evidence, 1. Methods: Twenty-seven male overhead athletes who had undergone surgery for capitellar OCD were included in the study. A single senior musculoskeletal radiologist blindly reviewed preoperative MRI of these OCD lesions. The radiologist reported the presence or absence of each of the 4 MRI signs indicating fragment instability as described by De Smet et al. The lesions were also classified according to the MRI staging system of Dipaola et al for characterizing the lesions. Intraoperative assessment of fragment stability was used as the gold standard. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were determined for fragment instability as assessed by MRI. Results: According to the MRI criteria by De Smet et al and the Dipaola et al staging system, 21 (78%) and 20 (74%) lesions were defined as unstable, respectively. The obtained results yielded a sensitivity of 89% and a specificity of 44% for diagnosing fragment instability using the De Smet et al MRI criteria and a sensitivity of 83% and a specificity of 44% using the Dipaola et al MRI staging system. The PPV and NPV for fragment instability were 76% and 67% using the De Smet et al criteria and 75% and 57% according to the Dipaola et al staging system, respectively. The overall correlation rate of Dipaola et al MRI and intraoperative stages was 41%. Conclusion: Preoperative MRI cannot precisely diagnose fragment instability of capitellar OCD that requires operative treatments in overhead athletes. Especially, MRI indicating stable lesions is considered not to be useful in predicting intraoperative instability of capitellar OCD in this study population.