Early detection of ischemic brain injuries by diffusion-weighted imaging after radiofrequency ablation for fetal reduction in monochorionic pregnancies.

BACKGROUND: This study aimed to investigate the additional advantages of magnetic resonance imaging (MRI), particularly diffusion-weighted imaging (DWI) over fetal ultrasound in the detection of acute ischemic cerebral injuries in complicated monochorionic (MC) pregnancies that underwent selective reduction by radiofrequency ablation (RFA). METHODS: This prospective cohort study was conducted on 40 women with complicated MC pregnancies who were treated by RFA. Fetal brain imaging by DWI and conventional MRI was performed either in the early (within 10 days after RFA) or late phase (after 3-6 weeks) in the surviving fetuses to detect both acute and chronic ischemic injuries. The presence of anemia after RFA was also evaluated by Doppler ultrasound. RESULTS: Overall, 13 of the total 43 fetuses (30.23%) demonstrated MRI abnormalities with normal brain ultrasound results including germinal matrix hemorrhage (GMH), extensive cerebral ischemia, and mild ventriculomegaly. Although seven fetuses with GMH eventually survived, fetuses that demonstrated ischemic lesions and ventriculomegaly on MRI died in the uterus. CONCLUSION: The absence of abnormal cerebral lesions or anemia on ultrasound and Doppler exams does not necessarily rule out fetal brain ischemia. Performing early MRI, particularly DWI seems to be a reasonable option for detection of early intracranial ischemic changes and better management of complicated multiple pregnancies which were treated by RFA.

Incidence of testicular microlithiasis in patients with ß-thalassemia major.

We assessed the prevalence of testicular microlithiasis by scrotal ultrasonography in ß-thalassemia major patients older than 10 years and evaluated the association with serum ferritin levels, calcium (Ca), phosphate (Ph), and parathyroid hormone levels (PTH). In this cross-sectional study, 132 male ß-thalassemia major patients from 300 male patients older than 10 years old were randomly evaluated by scrotal ultrasonography. Parathyroid hormone, calcium, phosphate, and serum ferritin levels were also evaluated. All of the patients were urologically asymptomatic. One hundred healthy age-matched subjects were selected as control group. Testicular microlithiasis was found in 16 patients and 1 individual in control group (12.1 vs 1 %; p = 0.003). Testicular microlithiasis was associated with age and high serum ferritin levels, but there was no association between Ca, Ph, and PTH levels; blood transfusion; and oral or subcutaneous iron chelation therapy. Also, there was no significant correlation between hyperparathyroidism, history of viral hepatitis, and splenectomy with testicular microlithiasis. The frequency of testicular microlithiasis in ß-thalassemia major patients was higher than previously reported. A correlation was found between testicular microlithiasis with age and serum ferritin levels, so regular and adequate iron chelator therapy (at least 10-12 h per day for 5-6 days a week) is recommended. We suggest a close observation and treatment with iron-chelating agents of these patients. Since testicular microlithiasis is occasionally associated with germ cell tumors, clinical and sonographic follow-up is recommended.

Microstructural white matter alterations associated with migraine headaches: a systematic review of diffusion tensor imaging studies.

The pathophysiology of migraine as a headache disorder is still undetermined. Diffusion tensor imaging (DTI) has significantly improved our knowledge about brain microstructure in this disease. Here, we aimed to systematically review DTI studies in migraine and survey the sources of heterogeneity by investigating diffusion parameter changes associated with clinical characteristics and migraine subtypes. Microstructural changes, as revealed by widespread alteration of diffusion metrics in white matter (WM) tracts, subcortical and cortical regions, were reported by several migraine DTI studies. Specifically, we reported changes in the corpus callosum, thalamic radiations, corona radiata, and brain stem. These alterations showed high variability across migraine cycle phases. Additionally, migraine associated with depressive/anxiety symptoms revealed significant changes in the corpus callosum, internal capsule, and superior longitudinal fasciculus. No significant WM microstructural differences were observed between migraine patients with and without aura. Overall, differences between chronic and episodic migraine showed inconsistency across studies. Migraine is associated with microstructural changes in widespread regions including thalamic radiations, corpus callosum, and brain stem. These alterations can highlight neuronal damage and neuronal plasticity mechanisms either following pain stimulations occurring in migraine cycle or as a compensatory response to pain in chronic migraine. Longitudinal studies applying advanced modalities may shed new light on the underlying microstructural changes in migraine subtypes.

The frequency of hypothyroidism and its relationship with HCV positivity in patients with thalassemia major in southern Iran.

INTRODUCTION: Hypothyroidism is one the most complication due to iron overload in patients with ß-thalassemia major (TM). On the other hand these patients are prone to Hepatitis C virus (HCV) infection that can cause  thyroid dysfunction by itself or as the side effect of treatment with interferon (INF) or IFN plus ribavirin. The aim of this study is to evaluate the association of hypothyroidism with HCV positivity and serum ferritin levels in patients with TM. METHODS: In this cross-sectional study, 201 randomly selected patients with TM who were registered at the Thalassemia Clinic of a tertiary hospital in Shiraz, southern Iran were investigated. Thyroid function tests and serologic screening assays for HCV seropositivity (HCV Ab and HCV-RNA) were conducted for all patients. RESULTS: Frequency of hypothyroidism was 22.9% including 19.9% subclinical hypothyroidism, 2% primary overt hypothyroidism and 1% central hypothyroidism. Eighty six patients (42.8%) were HCV Ab positive and 60 patients (29.9%) were HCV RNA positive. No significant relationship was found between hypothyroidism and HCV positivity or receiving IFN-α (P>0.05). Hypothyroidism showed a borderline significant association with high serum ferritin levels in TM patients (P=0.055). CONCLUSION: Our results showed no significant association between hypothyroidism and HCV infection in TM patients. It seems that the main mechanism of hypothyroidism in our patients is iron overload; however, for better evaluation a larger multicenter study is recommended.  Also due to the importance of consequences of HCV infection, more careful pre-transfusional screening of blood should be considered in TM patients.