Fractional change in apparent diffusion coefficient as an imaging biomarker for predicting treatment response in head and neck cancer treated with chemoradiotherapy.

BACKGROUND AND PURPOSE: ADC provides a measure of water molecule diffusion in tissue. The aim of this study was to evaluate whether the fractional change in ADC during therapy can be used as a valid predictive indicator of treatment response in head and neck squamous cell carcinoma treated with chemoradiotherapy. MATERIALS AND METHODS: Forty patients underwent DWI at pretreatment and 3 weeks after the start of treatment. The pretreatment ADC, fractional change in ADC, tumor regression rate, and other clinical variables were compared with locoregional control and locoregional failure and were analyzed by using logistic regression analysis and receiver operating characteristic analysis. Furthermore, progression-free survival curves divided by the corresponding threshold value were compared by means of the log-rank test. RESULTS: The fractional change in ADCprimary, the fractional change in ADCnode, primary tumor volume, nodal volume, tumor regression ratenode, N stage, and tumor location revealed significant differences between locoregional failure and locoregional control (P < .05). In univariate analysis, the fractional change in ADCprimary, fractional change in ADCnode, tumor regression ratenode, N stage, and tumor location showed significant association with locoregional control (P < .05). In multivariate analysis, however, only the fractional change in ADCprimary was identified as a significant and independent predictor of locoregional control (P = .04). A threshold fractional change in ADCprimary of 0.24 revealed a sensitivity of 100%, specificity of 78.7%, and overall accuracy of 84.8% for the prediction of locoregional control. Progression-free survival of the 2 groups divided by the fractional change in ADCprimary at 0.24 showed a significant difference (P < .05). CONCLUSIONS: The results suggest that the fractional change in ADCprimary is a valid imaging biomarker for predicting treatment response in head and neck squamous cell carcinoma treated with chemoradiotherapy.

Transient elevation of serum bilirubin (a heme oxygenase-1 metabolite) level in hemorrhagic stroke: bilirubin is a marker of oxidant stress.

Bilirubin (Bil) is the end product of heme catabolism. The production of Bil reflects heme oxygenase-1 expression in response to oxidative stress in various diseases. To assess the role of Bil as a marker of oxidative stress in cases of brain damage, we measured serum Bil concentrations in patients with hemorrhagic stroke. Serum levels of total Bil were measured in 20 subarachnoid hemorrhage patients with symptomatic vasospasms and in 23 patients with intracerebral hemorrhage; concentrations were measured every day for 14 consecutive days. Serum Bil levels were significantly elevated in the early phases in both groups. Moreover, transient elevation was observed on the day prior to the observation of clinical manifestations of symptomatic vasospasm after SAH. Bil, known to be a powerful antioxidant, was induced after hemorrhagic stroke, reflecting the intensity of oxidative stress. Plasma Bil concentrations might serve as a useful marker of oxidative stress in hemorrhagic stroke patients.

Estimation and comparison of rates of change in repeated-measures studies with planned dropout.

Many repeated-measures studies are designed to compare rates of change over time in responses among treatment groups. In such studies, some responses are often censored because some individuals drop out before completing the study. The Vitamin D(3) Trial was a repeated-measures, randomized clinical trial for secondary hyperparathyroidism in hemodialysis patients in which the efficacy of vitamin D(3) infusions for suppressing the secretion of parathyroid hormone (PTH) was compared among four dose groups during dialysis over 12 weeks. In this trial some patients dropped out because the protocol stated that any individual should have been off protocol if his or her serum calcium (Ca) level exceeded 11.5 mg/dL. While the dropout mechanism for the Ca level (secondary response) corresponded to the missing at random (MAR) assumption (because whether patients dropped out or not depended only on their previously recorded Ca level), the MAR assumption for the PTH level (primary response) was not justifiable without taking into account the effect of the Ca level. We consider estimation and comparison of several estimators of mean rate of change in the presence of dropout due to the selection process inherent in a study design like the Vitamin D(3) Trial. Simulation experiments are used to compare the bias and efficiency of several estimators of mean rate of change. The estimators based on a bivariate mixed-effects model outperform all other estimators in the primary response as well as in the secondary response. These estimators are applied to the Vitamin D(3) Trial data.

Neurons projecting to the retrocerebral complex of the adult blow fly, Protophormia terraenovae.

Anatomical study of neurons projecting to the retrocerebral complex of the adult blow fly, Protophormia terraenovae, was done by NiCl2 filling and immunocytochemistry. Retrograde filling through the cardiac-recurrent nerve labeled three groups of neurons in the brain/subesophageal ganglion: (1) paramedial clusters of the pars intercerebralis, (2) neurons in each pars lateralis, and (3) neurons in the subesophageal ganglion. The pars intercerebralis neurons send prominent axons into the median bundle and exit from the brain via the contralateral nervus corporis cardiaci. Based on the projection pattern, two types of the pars lateralis neurons can be distinguished: the most lateral pairs of neurons contralaterally extend through the posterior lateral tract and the remainder ipsilaterally extend through the posterior lateral tract. The neurons in the subesophageal ganglion run through the contralateral nervus corporis cardiaci. The dendritic arborization of the pars intercerebralis and pars lateralis neurons is restricted to the superior protocerebral neuropil and to the anterior neuropil of the subesophageal ganglion where the neurons in the subesophageal ganglion also project. Retrograde filling from the corpus allatum indicated that the pars lateralis neurons and a few pars intercerebralis neurons project to the corpus allatum, but that the neurons in the subesophageal ganglion do not. Orthograde filling from the pars intercerebralis and staining by paraldehyde-thionin/paraldehyde-fuchsin indicated that the pars intercerebralis neurons project primarily to the corpus cardiacum/hypocerebral ganglion complex. Immunostaining with a polyclonal antiserum against diapause hormone, a member of the FXPRLamide family, suggests that some of the subesophageal ganglion neurons contain FXPRLamide-like peptides.

Headache associated with pituitary adenomas.

The objectives of this study were to analyze the characteristics of headache in patients with pituitary adenoma and to investigate the mechanisms involved. Fifty-one patients (27 females and 24 males) with pituitary adenoma were examined. Nineteen (37.3%) of these patients (13 females and 6 males) had headache preoperatively. Most commonly, the headache was generalized (42.1%); overall headache was more frequent in the anterior half of the head (84.2%). Seventeen (89.5%) patients had bilateral headache. Headache was usually described as head heaviness (57.9%) and continuous (57.9%). Pulsating headache and dull pain were only reported by the female patients and were mostly intermittent. The mean age of patients with headache was younger than that of those without headache. Headache was more prevalent in patients with a prolactin-secreting adenoma (57.1%). There were no correlations between visual disturbances, hypopituitarism, tumor size, or cavernous sinus invasion and headache. Hemorrhagic pituitary adenoma in 4 (57.1%) of 7 patients did not always contribute to headache. The headache was improved after surgery in 14 (73.6%) of the 19 patients. In the male patients who survived postoperatively (5 of 6), headache was improved.

Occult intrasacral meningocele with tethered cord--case report.

A 32-year-old female presented with a history of intermittent, severe lower back pain, exacerbated by pregnancy and persisting for several years. Magnetic resonance (MR) imaging showed a sacral mass as a low signal intensity area on the T1-weighted image and a high signal intensity area on the T2-weighted image, consistent with a cystic structure containing cerebrospinal fluid. A tethered cord attached to the thecal sac was also confirmed. Sacral laminectomy revealed thinned sacral vertebral laminae, but no neuronal elements existed within the cyst. The cyst was attached to the distal thecal sac by a small fistula. The thecal sac was explored, revealing a thick filum terminale, which was transected. The severe pain resolved postoperatively. This type of meningeal cyst, often called "occult intrasacral meningocele," is best diagnosed by MR imaging. Surgery to obliterate the fistulous tract is the optimum treatment. Total removal of the cyst is unnecessary, but evaluation of other associated congenial abnormalities is important.

[Posterolateral extradural approach for total excision of spinal meningeal cyst (type Ia): case report].

Lateral thoracic meningocele is an uncommon disorder known to occur with high frequency in patients with neurofibromatosis. We report a case not accompanied by neurofibromatosis and describe the operative technique utilizing a posterolateral extradural approach. A 41-year-old man was referred to our cardiologic clinic for severe anterior chest pain. Plain chest X-ray demonstrated an oval mass lesion in the right 9th to 10th thoracic paravertebral region. Magnetic resonance imaging revealed a cystic mass at the 10th thoracic intervetebral foramen without distortion of the spinal cord. Signal intensity of the cystic mass was the same as the cerebrospinal fluid around the spinal cord. In the prone position, laminotomy of the 10th vertebral only was carried out. A pulsatile round mass in continuity with the dura mater was exposed. The wall of the sac, which was thickened with CSF, was identified. The neck of the menigocele was ligated with the help of an aneurysm needle. The patient's severe chest pain disappeared postoperatively.