Assessment of t2-weighted coronal magnetic resonance images in the investigation of pituitary lesions.

Magnetic resonance imaging is the most important diagnostic method in the investigation of the pituitary lesions. Our aim is to determine whether T2-weighted coronal images may be helpful in the evaluation of the pituitary gland with suspected pituitary adenomas. One hundred and sixty-seven patients were examined prospectively with T2-weighted coronal and T1-weighted coronal images enhanced with intravenous contrast material. The images were evaluated for the presence, the size, the location, and the ancillary signs including sellar floor erosion or ballooning, infindibulary deviation, convexity of the superior border of the gland, diffuse enlargement of the gland, and the invasion of the cavenous sinuses on both images. In forty-six (28%) patients lesions were revealed on both sequences. In twenty-one (12%) patients the lesions that were revealed on the T1-weighted images were not detected on the T2-weighted images. Positive predictive value, negative predictive value, sensitivity, specificity, and diagnostic accuracy rates of T2-weighted coronal images on the detection of the presence of lesions were 100%, 17.4%, 68.7%, 100%, and 87.4%, respectively. Both T2-weighted coronal and T1-weighted coronal images enhanced with intravenous gadolinium-based contrast material are important in the diagnosis of pituitary adenomas. T2-weighted coronal images could be used as a screening tool for the primary evaluation of the pituitary gland.

Staging of hip avascular necrosis: is there a need for DWI?

BACKGROUND: No comprehensive study has been performed to stage avascular necrosis of the hip using diffusion-weighted imaging (DWI). PURPOSE: To determine apparent diffusion co-efficient (ADC) alterations in hip avascular necrosis (AVN) and to determine variations of ADC values according to stages of disease. MATERIAL AND METHODS: The study is approved by our institutional review board and local ethical committee. Written informed consent was present for each subject. Thirty-five femoral heads of 21 cases affected by AVN were included in the study. Control group consisted of both femoral heads of 10 healthy volunteers. The hips affected by AVN were staged according to Ficat and Arlet classification system from I to IV. All cases underwent to routine hip magnetic resonance imaging (MRI) and DWI performed with a single-shot fast spin echo sequence at a b value of 600 s/mm(2). The ADC values were calculated automatically by placing ROIs on AVN lesions in affected patients and both femoral heads of control group. The median ADC value obtained from femoral heads of control group and that from AVN lesions were compared by Mann-Whitney U test. The median ADC values of AVN lesions at different stages were compared by Kruskal-Wallis test. RESULTS: The median ADC value of normal bone measured in control group was 185.5 ± 133.2 x 10(-6) mm(2)/s. The median ADC value measured in hip avascular necrosis lesions was 988.0 ± 332.7 x 10(-6) mm(2)/s. ADC values in hip AVN lesions were statistically significantly higher than normal bone marrow (P<0.01). The median ADC values of hips with avascular necrosis at stage I, II, III, IV were 817.5 ± 172.1 x 10(-6) mm(2)/s, 902.0 ± 181.0 x 10(-6) mm(2)/s, 1200.0 ± 363.2 x 10(-6) mm(2)/s and 1024.0 ± 324.0 x 10(-6) mm(2)/s, respectively. There was no statistically significant difference among AVN lesions at stages I, II, III and IV (P>0.05). CONCLUSION: Although DWI is a promising imaging tool that provides valuable diagnostic information in hip AVN, it fails to distinguish between different stages, and therefore is of limited value.

Recurrent respiratory papillomatosis with lung involvement.

The case of a 27-year-old male with recurrent respiratory papillomatosis including lung involvement is presented. Laryngotracheal papillomatosis with lung involvement is a rare entity associated with human papillomavirus infection. Computed tomography (CT) was essential in guiding diagnostic and therapeutic approaches. Knowledge about the findings of this disease is needed for correct diagnosis, since findings are nonspecific. Lesions may show malignant transformation; regular follow-up with CT is essential.

The value of diffusion-weighted imaging in the diagnosis of Marchiafava-Bignami disease: apropos of a case.

Marchiafava-Bignami disease (MBD) is characterized by demyelination and necrosis of corpus callosum encountered in chronic alcoholic patients. Etiology is the deficiency of vitamin B complex. Magnetic resonance imaging (MRI) in MBD typically reveals focal lesions of high T2 and FLAIR signal intensity in the corpus callosum. We here present a 42-year-old male alcoholic diagnosed as MBD on the basis of MRI and diffusion-weighted imaging (DWI) features. The patient totally recovered following appropriate vitamin B complex replacement therapy, despite reduced diffusion in the initial setting. This case report emphasizes on the important role played by MRI and DWI in the early diagnosis and follow-up of this potentially fatal disease.

Diffusion-weighted imaging of the appendicular skeleton with a non-Carr-Purcell-Meiboom-Gill single-shot fast spin-echo sequence.

OBJECTIVE: The objective of our study was to prospectively evaluate the signal-to-noise ratio (SNR) improvement in diffusion-weighted imaging (DWI) of the appendicular skeleton with the use of a newly developed non-Carr-Purcell-Meiboom-Gill (non-CPMG) single-shot fast spin-echo (SSFSE) sequence and to evaluate its effect on apparent diffusion coefficient (ADC) measurements. SUBJECTS AND METHODS: DWI of the bone was performed in 32 patients with an echo-planar imaging (EPI)-based sequence followed by a non-CPMG SSFSE technique. SNR and ADC values were measured over a lesion-free right femoral head. A score was assigned for each set of images to assess image quality. When a bone lesion was present, contrast-to-noise ratio (CNR) and ADC were also measured. Paired Student's t tests were used for statistical analysis. RESULTS: The mean (+/- SD) SNR values were 9.89 +/- 2.20 and 81.68 +/- 4.87 for EPI and non-CPMG SSFSE DWI, respectively. SNR values associated with the non-CPMG SSFSE technique were found to be significantly higher than those measured with the EPI-based DWI technique (p < 0.01). Mean ADCs of the bone were 0.57 +/- 0.20 and 0.29 +/- 0.15 x 10(-3) mm2/s, respectively, for EPI and non-CPMG SSFSE DWI. Image quality scores were higher for the non-CPMG SSFSE DWI technique (p < 0.05) than for the EPI-based DWI technique. Overall lesion CNR was found to be higher in DWI performed with the non-CPMG SSFSE technique. CONCLUSION: The non-CPMG SSFSE technique provides a significant improvement over the currently used EPI-based DWI technique and has the potential to be a powerful tool in imaging the appendicular skeleton.

Leontiasis ossea in a patient with hyperparathyroidism secondary to chronic renal failure.

Osteitis fibrosa describes the bone changes seen in renal osteodystrophy secondary to longstanding hyperparathyroidism. We report a 19-year-old man with longstanding chronic renal failure with a severe form of osteitis fibrosa affecting the jaws and other maxillofacial bones causing bizarre facial and dental deformity in a patient-uraemic leontiasis ossea.