Pretreatment differentiation of renal cell carcinoma subtypes by CT: the influence of different tumor enhancement measurement approaches.

PURPOSE: We conducted a retrospective study to evaluate the influence of different tumor enhancement measurement approaches on the ability of computed tomography (CT) to differentiate between solid forms of clear cell renal cell carcinoma (RCC), other RCC histologic subtypes and oncocytomas. Different RCC subtypes have a diverse range of malignant potential; consequently, the information about RCC subtype obtained using minimally invasive imaging method before the treatment could allow the more accurate therapy planning. Differentiation of ccRCCs from oncocytomas is important because oncocytomas are usually benign tumors which could be treated conservatively. METHODS: CT images of 113 patients with 118 solid renal tumors were evaluated. The imaging protocol consisted pre-contrast and post-contrast images during the arterial and nephrographic phases. Renal tumor attenuation values were measured using region of interest covering as much of the solid enhancing tumor tissue as possible. Tumor attenuation values and tumor enhancement ratios were correlated with histologic subtype. One hundred of tumors were diagnosed as clear cell RCC, nine as non-clear cell RCC and nine as oncocytoma. RESULTS: Tumor attenuation values of >74 HU on the arterial phase scans significantly correlated with clear cell RCC (Az 0.73). The tumor-to-aorta enhancement ratios calculated on tumor attenuation values measured on the arterial phase scans had a cutoff value of >0.29, which significantly correlated with clear cell RCC (Az 0.79). All ROC curves for differentiating the clear cell RCC from oncocytomas have area under the curve too small (0.5 or less) to have chose cutoff value with sensitivity and specificity that could be applied in clinical work. CONCLUSION: Enhancement measurements of renal carcinomas on CT images in the arterial phase can be used as an auxiliary method in the pretreatment differentiation of solid forms of the most frequent RCC subtypes in patients not suitable for core biopsy but who are suitable for minimally invasive treatment methods and/or targeted therapy.

Radiographic validation of manual functional analysis of temporomandibular joint osteoarthritis.

The finding of osteoarthritis of temporomandibular joint (TMJ) obtained by clinical diagnosis, i.e. manual functional analysis (MFA) and the finding obtained by magnetic resonance imaging (MRI) as the gold standard were compared in 30 patients (mean age 52.6) diagnosed with osteoarthritis, selected out of 140 consecutive patients diagnosed with a TMJ disorder by MRI. The clinical parameters were symptoms of pain in the TMJ region, crepitations, and absence of clicking, which was confirmed by manual examinations as part of MFA. A positive MRI finding included flattening, subchondral degenerative changes with or without intact cortical bone, osteophytes and subchondral degenerative cysts of joint surfaces. The validity of MFA for osteoarthritis was as follows: sensitivity 0.38, specificity 0.91, positive predictive value (PPV) 0.77 and negative predictive value (NPV) 0.65. MRI examination revealed disk displacement (DD) without reduction in 12 (40.00%) patients and DD with reduction in one (3.33%) patient. The finding of passive compressions for the osteoarthritis diagnosis depending on DD showed sensitivity of 0.29, specificity of 0.95, PPV 0.67 and NPV 0.78. Although MFA significantly improves validity of clinical diagnosis when differentiating a myogenic from TMJ disorder, clinical determination of osteoarthritis is not satisfactory. Nonspecific clinical signs and symptoms accompanied by predominant pain in the TMJ on dynamic but not on passive manual examinations cannot help differentiate DD from osteoarthritis.

Temporomandibular disorders and occlusion.

Occlusion has an important place within the multifactorial concept of the temporomandibular disorder (TMD) etiopathogenesis as well as in every form of dental treatment. The modern concept of treatment of these disorders differentiates initial and definitive forms of treatment. The aim of this paper is to analyze recent viewpoints on the role of occlusion in the etiopathogenesis and treatment ofTMDs. Masticatory muscles and temporomandibular joints are directly connected with occlusal relations and TMDs are traditionally linked with occlusal disorders. The initial occlusal treatment can be applied to all TMD patients, regardless of their having intact teeth with respect to physiological occlusal relations and in patients in need of orthodontic or prosthodontic treatment or an oral surgical procedure. On managing TMD patients, there are doubts about the indications for definitive treatment and whether there has been a possibility of treating a painful TMD by reversible treatment modalities, that is, by initial treatment. Other types of orofacial pain such as trigeminal neuralgia can be comorbid with TMDs but also result in unnecessary procedures on the teeth and prosthodontic work if they are not recognized. Although dental profession mainly recognizes the importance of occlusal treatment of TMD problems, their relationship is controversial because it is not strictly demonstrated in numerous scientific studies. Occlusion is not the dominant cause of TMD problems.

Multiphase computed tomography of malignant kidney tumors: radiologic-pathologic comparison.

The aim of this retrospective study was to evaluate diagnostic test parameters of multiphase spiral computed tomography (CT) of the kidneys in the assessment of malignant renal tumors. Fifty-one patient records were reviewed. The imaging protocol included unenhanced and postcontrast scans during arterial and nephrographic phase. CT findings were compared with pathology findings to assess the value of spiral CT (sensitivity, specificity, negative predictive value, positive predictive value and accuracy) in the detection and characterization of tumors, and in the evaluation of local extension of malignant renal tumors. Spiral CT had a 96.08% sensitivity and accuracy in the detection of tumors. Characterization of renal tumors with CT had a sensitivity of 94.12% and accuracy of 96.08%. In the detection of fibrous capsule penetration, CT reached a sensitivity of 91.97% and specificity of 51.28%. In the evaluation of canal system propagation, the sensitivity was 100% and specificity 90.70%. CT had a sensitivity of 75%, specificity of 95.75% and positive predictive value of 60% in the evaluation of regional lymph node involvement. In the detection of the main renal vein invasion, CT showed 60% sensitivity and 100% specificity. Spearman's rank correlation coefficient between the mean tumor size on CT images and renal specimen was 0.916. In conclusion, multiphase spiral CT has satisfactory diagnostic parameters in the detection, characterization and evaluation of local extension of renal tumors except for detection of the main renal vein invasion.

Study of temporomandibular joint disorder in older patients by magnetic resonance imaging.

OBJECTIVES: To compare characteristics in older patients in a sample of the general population of those with temporomandibular joint disorder (TMJD). MATERIALS AND METHODS: A prospective study was carried out between 2001 and 2008 in patients with TMJD. The whole sample consisted of 141 patients divided in two groups: 31 patients aged over 60 (median age 67.9, ranging from 60 to 82) and the remaining 110 patients (median age 36.3, ranging from 12 to 59) who were seeking treatment. Clinical diagnostics was confirmed by MRI. Pain intensity was rated on a visual analogue scale (VAS 0-10). RESULTS: There was no statistical difference between average pain in older patients (6.2) and patients aged up to 59 (5.7) evaluated by VAS. There was a statistically significant difference (p = 0.002) in pain duration: older patients reported shorter duration of experienced pain (7.8 months) than patients aged up to 59 (12.2 months). CONCLUSION: In this study, it was found that 22% were older patients with TMJD. A higher level of anxiety was shown in both patients' groups, regardless of shorter pain experience in the older patients.

Temporomandibular joint development and functional disorders related to clinical otologic symptomatology.

Temporomandibular disorders (TMDs) are a form of musculoskeletal pain of the temporomandibular joint (TMJ) and/or masticatory muscles of nonspecific etiology. In this study, the relationship between embryonic and anatomic-topographic similarities of the TMJ and the ear was analyzed, i.e. secondary otologic symptoms that can be closely connected to TMJ disorder. Nonspecific otologic symptoms are not primary diagnostic symptoms of TMD, but may cause diagnostic confusion due to patients' inability to correctly locate the origin of pain. The most common otologic symptoms that can be related to TMDs are otalgia, tinnitus and vertigo. Otorhinolaryngologists have to differentiate between primary otologic symptoms and those caused by TMJ disorders. In TMD diagnosis, manual techniques are used to determine the arthrogenic or myogenic form, whereas in the diagnosis of arthrogenic disorders magnetic resonance imaging is indicated as the highly specific imaging method ofjoint disk and osteoarthritic changes. Symptomatic treatments for TMD as well as the etiologic diagnosis of the pain require multidisciplinary cooperation between dentists and medical specialists.

Superoxide dismutase and cytochrome P450 isoenzymes might be associated with higher risk of renal cell carcinoma in male patients.

Literature data support the hypothesis that oxidative stress and the accompanying antioxidant defense might play an important role in renal cell carcinoma (RCC) growth and progression. It is also known that the incidence of renal tumors is two times higher in men than in women. Thus, the aim of this study was to determine whether the oxidant/antioxidant profile of renal cell carcinoma tissue, adjacent to tumor tissue and nontumor tissue was different in male and female patients. Significantly higher lipid peroxidation (LPO) in renal cell carcinoma tissue compared to nontumor tissue was demonstrated only in male patients. Besides, gender-related difference in copper zinc superoxide dismutase (CuZnSOD) and manganese superoxide dismutase (MnSOD) in nontumor and renal cell carcinoma tissue was obtained at the level of transcription, translation and activity of these antioxidant isoenzymes. Morever, we demonstrated that the gene expression of 3 CYPs out of 7 was altered; CYP2D6 mRNA was decreased in both sexes while gender-related suppression of mRNA for CYP2E1 (women) and CYP2C19 (men) was observed. Taken together, these parameters might be potentially responsible for higher risk of renal cell carcinoma in men than in women.

Correlation between magnetic resonance imaging and histopathology in differentiation of pancreatic diseases.

In the last four decades, the incidence of pancreatic cancer has tripled in Western countries. More than 90% of all pancreatic cancers are detected in the advanced stage of the disease when surgical treatment is no longer possible and survival after initial diagnosis is usually very short. The aim of this study was to correlate magnetic resonance imaging (MRI) established diagnosis of chronic pancreatitis, benign lesion and malignant neoplasm with final histopathology. The study included 29 patients in whom the nature of pancreatic pathology could not be determined clinically and by other imaging modalities including abdominal ultrasonography, endoscopic retrograde cholangiopancreatography and multislice computed tomography. MRI examination was performed and radiological report was compared with histopathology assessment of the pancreatic lesion detected. The data obtained indicated systematic conformity between radiological and histopathology findings, confirmed high diagnostic accuracy of MRI for selected pancreatic pathology, and demonstrated the role of MRI as a problem solving diagnostic imaging modality in undetermined pancreatic changes.

Preoperative staging of renal cell carcinoma using magnetic resonance imaging: comparison with pathological staging.

We have retrospectively assessed the accuracy of our MRI protocol on 1.0-T MRI system for preoperative staging of renal cell carcinoma using the 2002 TNM staging system and pathological staging as the gold standard. Medical records of 48 patients (mean age, 56.28 years) with 57 renal tumors were reviewed: 52 malignant renal tumors were found; most of the patients were staged T1N0M0. In our study, κ test revealed excellent agreement between all three classes of the TNM staging system.

Magnetic resonance imaging in the diagnosis of malignant tumors of the maxillofacial region.

Magnetic resonance imaging (MRI) is a radiological imaging method that has not yet found routine application in the detection and assessment of malignant tumors of the maxillofacial region. The aim of this study was to evaluate MRI in the detection, diagnosis and differential diagnosis of malignant tumors of the maxillofacial region. This prospective study included 42 patients with clinically confirmed malignant tumors of the maxillofacial region. All patients were examined by MRI. This imaging method was evaluated for the ability to detect tumor location and to analyze dimensions and structure of the tumor, bone involvement, effect on neurovascular structures and extension to soft tissues. MRI results were compared with histopathologic and intraoperative findings as the 'gold standard' methods. MRI identified all of the clinically confirmed tumors. The sensitivity for tumor location was 94.4%, tumor necrosis 93%, hemorrhage 93.3% and bone involvement 91.4%. The specificity for tumor location was 84%, tumor necrosis 92.8%, hemorrhage 92.8% and bone involvement 85.7%. In the evaluation of soft tissue tumor extension to bone structures, MRI sensitivity and specificity was 94.4% and 88.2%, respectively. The sensitivity for perineural infiltration and tumor involvement of vascular structures was 91% and 91.6%, respectively. The specificity for perineural infiltration was 96.7% and for tumor involvement of vascular structures 88%. MRI sensitivity and specificity for intracranial extension, intraorbital propagation, extension to pterygopalatine fossa and other surrounding anatomic spaces was 93.5% and 90.9%, respectively. MRI proved advantageous for the ability to distinguish neurovascular structures from adjacent soft tissues without the use of intravenous contrast media. Study results demonstrated MRI to provide valuable information in the analysis of tumor structure, bone involvement and extension to soft tissues of malignant tumors of the maxillofacial region.

Magnetic resonance imaging study on temporomandibular joint morphology.

Magnetic resonance imaging (MRI) has enabled the accomplishment of a more effective diagnostics of temporomandibular disorders (TMD). The sample included 40 patients with clinical symptoms of disc displacement (DD) of temporomandibular joint (TMJ) and 25 subjects included in our study were asymptomatic. DD were diagnosed by clinical examinations which were subsequently confirmed by MRI. DD was found in 18% of the TMJs of the asymptomatic patients. The highest prevalence of total DD without reduction was found in 44.1% of the patients' joints subsequently followed by total DD with reduction comprising 34.9% of the TMJs and by partial DD with reduction comprising 21% of the TMJs. This study may help us clarify the complicated relationship which exists between the radiographic and clinical findings of TMJ disorders.

A quantitative analysis of splint therapy of displaced temporomandibular joint disc.

OBJECTIVES: The effects of the Michigan splint on the change in disc displacement (DD) as well as the position of the condyles were determined by metrical analysis using magnetic resonance imaging (MRI). METHODS: Twenty-five patients with clinical DD symptoms were treated by means of the Michigan splint, and an assessment of the effects of the splint was conducted or verified by MRI before and during the period of therapy, 5 months follow-up. The positions of the condyles and the disc were calculated from the MRI in the parasagittal plane. RESULTS: There were no changes in the positions of the disc and condyles in the physiological joints of the patients (n=23) prior to and during the time the splint was in place (p>0.05). The splint achieved a DD decrease (p<0.05), and pain was eliminated in 69.2% of the DD joints with reduction (n=13). As far as the DD joints without reduction (n=13) are concerned, pain was eliminated in 74.9% of the joints, that is, without any change in the positions of the disc and condyles (p>0.05). CONCLUSIONS: The evaluation of the Michigan splint therapy showed that it has no influence in the repositioning of the DD joints without reduction, but the DD joints with reduction have a limited positive effect. In both forms of these displacements, conditions for the elimination of the clinical symptoms are created.

Occlusion in patients with temporomandibular joint anterior disk displacement.

The aim of this study was to determine the correlation between the static and dynamic occlusal factors in patients with anterior disk displacement (DD) and to compare it with occlusion in asymptomatic individuals. The study included a group of 40 patients with DD (median age 35.5) and a control group of 25 students of dental medicine (median age 23.4). In all subjects, the position, i.e. DD was determined by magnetic resonance imaging of temporomandibular joints. The study was focused on data gathered by direct analysis of occlusion: relationship between the molars (Angle class), horizontal and vertical overlap, preservation of occlusal contacts between the molars (Eichner classification), difference between contact points in maximal intercuspidation and centric position, and contact points on the laterotrusive and mediotrusive side. There was a statistically significant difference in tooth contact in maximal intercuspidation and centric positions between patients and asymptomatic subjects (p < 0.0001). There was also a difference between occlusal contact points on the mediotrusive side (p < 0.05) since the hyperbalanced contacts were only determined in asymptomatic subjects. Study results support the fact that a number of occlusal factors are related to DD. The fact that hyperbalanced contacts were only determined in asymptomatic subjects suggests that their mutual etiopathogenetic correlation is not quite clear.

MR assessment of bile duct size in healthy individuals: comparison with US measurements.

The purpose of the study was to determine the difference in extrahepatic bile duct (EBD) size measured by magnetic resonance (MR) compared with those measured by ultrasound (US). Changes of EBD size related to aging were analyzed too. Size of EBD was measured in 76 randomly selected healthy individuals. Three radiologists blinded to the result of other study preformed measurements by US and three different T2 weighted MR sequences. Correlation and linear regression analysis of obtained data were performed. The mean diameter of EBD measured by US was 3.17 mm and by MR was 3.14 mm on thick slab rapid acquisition with relaxation enhancement (TSE), 3.26 mm on thin section single-shot TSE (HASTE) and 3.30 mm on coronal fully rewound gradient echo (True FISP). There was no statistical difference between US and different MR sequences (p < 0.05). A trend of increase of EBD with age (0.0155 mm per year, p = 0.0954) was observed. Size of EBD highly correlated for each MR sequence with US measurement validating use of MR as a reliable method for evaluation of EBD size. This conclusion is stressed by increase of EBD size with age demonstrated by all measuring methods.

The risk of sports activities--the injuries of the Achilles tendon in sportsmen.

The aim of this study was to determine whether professional sports activities and intensive training practice affect pathological changes of the Achilles tendon. We also aimed to investigate whether these injuries primarily occur earlier or later in life. This was a cross sectional study of 214 athletes and non-athletes between the ages of 17-66. Participants were divided into four groups: 63 active young athletes, 64 young persons not involved in sports, 6 elderly athletes and 58 elderly people who did not participate in intensive athletic activities during their lifetimes. Ultrasound measurements of the Achilles tendon were performed on all participants. All participants also completed a self-administered survey to collect demographic information and data on athletic participation. Data were analyzed using the chi-square test and Fisher's exact test. Overall, those who were active athletes sought medical care more often than those who did not participate regularly in sports. Twenty-seven (33%) of young athletes had some Achilles tendon pathology, compared to 9 (14%) younger non-athletes. A total of 36 (64%) of elderly athletes were diagnosed with Achilles tendon disorders, compared to 15 (26%) of elderly people who were not active in sports. Microtears, acute tendonitis and peritendonitis were associated with younger age. By contrast, calcifications, scar tissue, and partial or complete rupture were only seen in the elderly

Using magnetic resonance imaging to identify the lumbosacral segment in children.

Identification of the lumbosacral (L-S) segment on magnetic resonance (MR) images is important for appropriate treatment of disease in the lumbosacral (L-S) area. In the study, data obtained from plain A-P radiographs of the L-S spine and sagittal MR imaging scans (sagittal T1- and T2-weighted sequences) of the L-S spine and sacrum with the coccygeal bone, are analyzed. Twenty-six children aged 10 to 14 years were examined for back pain. On the standard A-P radiographs of the L-S spine, a L-S transitional vertebra as classified according to the method of Castellvi et al. was found in 17 subjects. The problem arose as to whether this was lumbalisation or sacralisation, and how to determine which vertebra was L5 wich S1. On the sagittal MR imaging studies the same question applied. A need emerged for a simple method which would identify the L-S segment on the sagittal MR imaging studies of the L-S spine in children so that in case of a tumor, inflammation, spondilolystesis, or protrusion of a disc, the level in the L-S spine where the problem is localized can be accurately identified. To this objective we selected the method using detection of the S1 vertebra. This involved that, in addition to the sagittal MR imaging scans of the L-S spine, sagittal images of the sacrum and coccygeal bone be also obtained. on the T2-weighted sequence, the sacrum can be clearly distinquished from the coccygeal bone. By counting from the S5 up, the S1 vertebra can be accurately identified. Determination of the S1 vertebra enables detection of the L5 vertebra and, in turn, of all other lumbar vertebrae. In patients in whom a T2-weighted MR studies were done S1 could be precisely determined and so could the L5 vertebra. In this process, whether the patient had a transitional vertebra or whether there was lumbarisation or sacralisation was irrelevant.

[Initial treatment of temporomandibular joint osteoarthritis]. / Inicijalna terapija osteoartritisa celjusnoga zgloba.

The diagnostic procedure and the initial treatment of a female patient suffering from temporomandibular disorder is described. Osteoarthritis and the discopathy of the temporomandibular joint were diagnosed both clinically and by magnetic resonance imaging. Anxiety was confirmed by measuring instrument State-Trait Anxiety Inventory. Pains in temporomandibular joints were removed after the initial treatment in which the occlusion splint had been used so that conditions for carrying out the definite occlusal treatment were fulfilled.

[Spiral CT angiography in practice]. / Spiralna CT angiografija u praksi.

Incidence of vascular diseases and development of new radiologic techniques in the last three decades has given strong impuls for introduction of non-invasive vascular diagnostic methods. Thanks to the introduction of Doppler ultrasound, new types of computed tomography (CT) and magnetic resonance (MR) scanners, non-invasive vascular diagnostic methods are replacing conventional invasive (catheter) angiographic methods. Computed tomographic angiography (CTA) is a noninvasive vascular diagnostic method based on continuous scanning with CT scanner during intravenous application of contrast material. Performing of CTA is possible after introduction of spiral CT technique whose characteristics are short imaging time and volumetric data acquisition. The main goal of this article, based on our experiences, is to review the role of CTA, performed on single-slice CT scanner, in managment of patients with vascular pathology.

Retained surgical textilomas occur more often during war.

Retained surgical textile foreign bodies are a problem despite precautions taken by surgeons. Computed tomography (CT) is a method of choice in diagnosing the cases of retained textilomas. Over 12 years, we diagnosed 11 acute textilomas in 10 patients in the early postoperative period within 3 months after abdominal surgery. The presence of considerable amount of air bubbles within textile fibers was the most representative sign. A 3-10 mm wide peripheral rim was present in all textilomas. In additional 3 cases, chronic, encapsulated foreign body granulomas were found, two were mimicking renal neoplasms. All granulomas contained discrete or coarse calcifications. The period between surgery and CT diagnosis was from 6 months to 14 years in chronic lesions. It is important to emphasize that 9 textilloma in 8 patients were associated with the years of war in Croatia (1991 and 1992), in hospitals on battle fronts, where surgeons worked under extremely strenuous conditions and with great inflow of wounded soldiers and civilians.