Macular pigment and macular volume in eyes of patients with cystic fibrosis.

BACKGROUND: Because patients with cystic fibrosis (CF) are living longer, chronic malabsorption of carotenoids associated with CF resulting in decreased macular pigment (MP) may affect macular long-term health in later-life pathology. This study compared the macular pigment optical density (MPOD) and corresponding central macular volume (MV) of adult CF subjects and age-matched normal controls subjects to determine whether chronic malabsorption associated with CF could adversely affect macular photoreceptor anatomy. OBJECTIVE: Our aim was to compare MPOD with measurements of central MV in CF patients with age-matched controls. Design. In nine adult CF patients (ages: 29-46) without a history of carotenoid supplementation or known retinal or optic nerve disease MPOD and MV were measured by heterochromatic flicker photometry (HFP) and optical coherence tomography (OCT), respectively, and compared to results obtained from 14 age-matched controls. RESULTS: MPOD was significantly reduced at 15' and 30' eccentricities in CF subjects compared to normal subjects (mean difference -0.21 at 15', -0.25 at 30', p < 0.005). No significant difference, in MV noted at any of the eccentricities tested between CF and normal subjects (CF: normal MV ratios ranged from 0.94 to 1.1 for all eccentricities with p > 0.1 at all eccentricities). Best corrected vision acuity and fundus examination were normal in all subjects. CONCLUSIONS: Unsupplemented CF patients have markedly lower levels of macular carotenoids (e.g., lutein and zeaxanthin), but well-maintained visual function and no significant reductions in central MV primarily composed of macular photoreceptors. Future studies are needed to determine whether the lifelong decrease in protective central retinal carotenoids predisposes CF patients to later-life retinal pathology.

Are T1 weighted images helpful in MRI of cervical radiculopathy?

MRI in patients with cervical myelopathy or radiculopathy usually includes T(1) weighted (T(1)W) and T(2) weighted (T(2)W) images. We prospectively examined a hypothesis that T(2)W alone is sufficient to diagnose the cause of cervical myelopathy and radiculopathy and that the T(1)W sagittal images do not provide additional useful information. 30 patients presenting with a history of cervical radiculopathy with or without myelopathy were prospectively assessed by MRI. Those with a history suggestive of intrinsic primary cord disease or who had previously had surgery were excluded. Two neuroradiologists, blinded to the clinical information, separately viewed the sagittal and axial T(2)W images alone, and at a later time, the full set of T(1)W and T(2)W images. Image quality, location and severity of disease and confidence of diagnosis at each level were scored on 4- or 5-point scales. The T(1) sequences did not demonstrate any significant lesions not already seen on the T(2)W images alone. The T(1)W sequence may safely be omitted in patients with radiculopathy.

Triploidy: antenatal sonographic features with post-mortem correlation.

A retrospective study was performed comparing the antenatal ultrasound (US) scan features with post-mortem findings in 20 triploid fetuses surviving beyond the first trimester. US scans showed a range of abnormalities including oligohydramnios (60 per cent of cases), intra-uterine growth retardation (IUGR, 55 per cent), central nervous system (CNS) abnormalities (45 per cent), and placental abnormalities (55 per cent). There were obstetric complications in 30 per cent of cases. Post-mortem examinations confirmed these findings but also demonstrated additional anomalies including facial dysmorphism, limb abnormalities (syndactyly, talips equinovarus and thigh muscle hypertrophy), and anomalies of cardio-vascular, respiratory and genito-urinary system. The placenta was normal in 16 per cent of cases, enlarged with cystic change in 47 per cent, small in 32 per cent and infarcted in 5 per cent of cases. Various factors including oligohydramnios, abnormal fetal position, less sophisticated equipment in mid-1980s and relative inexperience of early observers contributed to the reduced sensitivity of US scans in diagnosis of various defects. However, triploidy should be considered in all cases showing early second-trimester IUGR with or without oligohydramnios, a major CNS abnormality and/or an enlarged placenta with or without changes of partial hydatidiform mole. As triploidy is associated with increased obstetric complications, fetal karyotyping should be offered to confirm the diagnosis so that appropriate obstetric intervention can be instituted.

The right inferior lung margin: anatomy and clinical implication.

Medical students and clinicians have, for generations, based their knowledge and application of anatomy on the study of cadavers which have been fixed in formalin. Assumptions are made that structures maintain the same relationship in the living as in the dead. Such a belief is untrue in respect of the inferior extent of the lung and pleura into the posterior diaphragmatic sulcus. This study of the plain abdominal radiographs of 100 adult patients demonstrates a clear difference between the classical anatomical teaching, which describes a potential space containing only pleura in the recess, and our finding that in the living patient lung extends deep into the sulcus. In 80% of patients, lung is seen to lie at or below the level of the 12th rib, while in 18% lung reaches the level of the body of L1. Medical students should be made aware of this and clinicians should approach the liver, adrenal gland and kidney posteriorly with caution in order to avoid traversing lung and pleura.

Gas-containing ganglia of the hip.

Three cases of ganglia related to the hip containing gas are presented. Gas may be shown by conventional radiography, linear tomography or computed tomography. All three cases had advanced degenerative disease of the joint. In degenerative disease, ganglia form through a pathway which allows the transfer of intra-articular gas into the ganglion. It is important to differentiate this phenomenon from overlying bowel gas and other causes of gas within soft tissues. It is the most specific radiological feature of ganglia around the hip.