ABSTRACT
BACKGROUND AND PURPOSE: To date, no pathophysiological model has sufficiently accounted for all the findings encountered in patients with idiopathic intracranial hypertension (IIH). Intracranial elastance is an index of volume-buffering capacity known to play a role in certain disorders of cerebrospinal fluid (CSF) dynamics, which has not been previously investigated in relation to IIH patients. METHODS: This was a single-center retrospective cohort study from 1 July 2011 to 1 July 2016. Values for opening pressure (PO ), closing pressure (PC ) and volume (V) of CSF removed were collected, as well as demographic and clinical covariates. Intracranial elastance (E) and pressure-volume index (PVI) were calculated according to established equations: E = (PO -PC )/V and PVI = V/log10 (PO /PC ), respectively. Those with an alternative central nervous system pathology, including meningitis, encephalitis and normal pressure hydrocephalus were excluded. Eligible patients were subdivided into two groups based on final diagnosis: a control group and an IIH group. RESULTS: In our cohort (n = 49), a significant association of both E (P < 0.0001) and PVI (P = 0.005) with a diagnosis of IIH was observed. Median E was 0.45 [interquartile range (IQR) 0.29-0.63] in the control group and 1 (IQR 0.59-1.29) in the IIH group, and median PVI was 98.07 (IQR 59.92-135.86) in the control group and 64.1 (IQR 42.4-91.7) in the IIH group. Neither E nor PVI were significantly associated with age, gender or body mass index. PVI was independent of opening pressure. CONCLUSIONS: As calculated by clinically accessible indices, our study provides evidence that intracranial elastance is increased in IIH, reflecting a novel insight into disease pathogenesis.
Subject(s)
Pseudotumor Cerebri/physiopathology , Adult , Elasticity , Female , Humans , Male , Middle Aged , Pseudotumor Cerebri/cerebrospinal fluid , Retrospective Studies , Young AdultABSTRACT
Magnetic reasonance (MR) enterography enables high contrast resolution depiction of the location and cause of bowel obstruction through a combination of predictable luminal distension and multiplanar imaging capabilities. Furthermore, because the patient is not exposed to ionizing radiation, sequential "dynamic" MR imaging can be performed repeatedly over time further facilitating depiction of the site and/or the cause of obstruction. With increasing availability of MR imaging and standardization of the oral contrast medium regimens, it is likely that this technique will assume an ever-increasing role in the evaluation of small bowel dilation in the coming years. We illustrate the utility of MR enterography in the evaluation of small bowel dilation, whether it be mechanical, functional (e.g., ileus), or related to infiltrative mural disease.
Subject(s)
Intestinal Diseases/diagnosis , Intestine, Small/pathology , Magnetic Resonance Imaging, Cine/methods , Adult , Aged , Contrast Media , Dilatation, Pathologic/diagnosis , Enteritis/diagnosis , Female , Hernia/diagnosis , Humans , Ileus/diagnosis , Image Processing, Computer-Assisted/methods , Intestinal Neoplasms/diagnosis , Intestinal Obstruction/diagnosis , Intestinal Volvulus/diagnosis , Male , Middle AgedABSTRACT
Patients who present during pregnancy with acute abdominal symptoms often present a significant diagnostic challenge. Although ultrasound is often the first mode of abdominal imaging, in complex cases further imaging is often necessary. MRI of the small bowel has been made possible with the development of rapid scanning techniques. This has increased the attractiveness of a modality whose benefits include multiplanar imaging, excellent soft tissue contrast and the avoidance of ionizing radiation. With these capabilities MRI has been shown to be a useful adjunct when imaging the small bowel in pregnancy. Although MRI has been employed to investigate small bowel obstruction in the obstetric setting, to date there have been no reports of MR identifying small bowel obstruction secondary to extrinsic compression from a gravid uterus. During pregnancy, small bowel obstruction is most commonly attributed to adhesions. However, there are also antenatal occurrences of small bowel obstruction secondary to uterine compression. We present the MRI findings of an unusual case of small bowel obstruction occurring secondary to compression from a 32-week gravid uterus, in a patient with an end ileostomy. Furthermore, while clinical history and examination are fundamental to diagnosis of intestinal obstruction, the following case highlights the value of MRI in pregnancy as a confirmatory test.
