Persistent trigeminal artery as a rare cause of vertebrobasilar insufficiency.

The persistent trigeminal artery (PTA) is the most common foetal carotid-basilar anastomosis which may persist into adult life. In the literature there are numerous papers referring to the anatomical characteristics of this anomalous vessel. In the majority of cases PTA is an incidental finding and its clinical significance has been debated. Some authors describe the coincidence of PTA with various clinical syndromes. However, there are few reports linking PTA with the symptoms of vertebrobasilar insufficiency. We present a patient with a 3-year history of recurrent dizziness and impaired vision, precipitated by physical activity, in whom neuroimaging techniques revealed a left PTA. In our case the occurrence of PTA might have been related to the clinical manifestation and the potential mechanism will be discussed.

The analysis of renal artery cross-section area and kidney volume in computed tomography angiography.

BACKGROUND: The purpose of this study was to assess the relationship between renal artery cross-section area and kidney volume with consideration of anatomical variants of renal arteries, sexual dimorphism and lateralisation. MATERIALS AND METHODS: Two hundred and two patients, 104 women and 98 men, aged 57.3 ± 16 years were examined using computed tomography angiography (CTA) of abdominal aorta for various reasons. The cross-section areas of renal arteries were measured automatically with a vessel tracking programme and summed up on each side in case of the presence of additional renal arteries. The kidneys were measured manually. RESULTS: Additional renal arteries (ARA) were found in 68 (33.7%) patients. Fifty-three (77.9%) of them had one, 11 (16.2%) two and 4 (5.9%) three ARAs. Bilateral ARAs occurred in 10 cases (14.7% patients with ARA). Proximal branching of renal artery occurred in 36 (8.4%) renal arteries. The cross-section area of the largest renal artery depended on the number of ipsilateral renal arteries. Mean cross-section area of the main left renal artery was larger than on the right side (28.52 mm2 vs. 25.36 mm2, p < 0.01) in the whole analysed group. Strong sexual dimorphism in renal artery cross-section area was observed (p < 0.01) in favour of men (31.3 mm2 in men and 22.9 mm2 in women). Mean total renal artery cross-section area has positively correlated with kidney volume (p < 10-13) in both sexes with Pearson correlation value of 0.5. CONCLUSIONS: The cross-section area of renal arteries correlated positively with kidney volume in both sexes. Presence of ARAs does not influence the sum of cross-section areas of renal arteries. In case of a difference between left and right renal artery cross-section area with symmetrical kidneys, it is necessary to look for ARA.

Preoperative Computed Tomography Parameters and Deterioration of Remaining Kidney Function in Living Donors.

INTRODUCTION: After living kidney donation, a decrease of kidney function (described as estimated glomerular filtration rate [eGFR]) is observed in majority of donors. However, the loss is more significant in some patients without an explicable reason. The aim of this study was to identify quantitative parameters in computed tomography (CT) of the abdomen that would predict greater eGFR reduction after kidney removal. MATERIAL AND METHODS: One hundred and ten preoperative multiphase CT examinations of the abdomen of kidney donors were analyzed for the following renal parameters: cortex, parenchyma and pyramids volume, scarring thickness (low grade: <1 cm, high grade: >1 cm), cortical gaps, vascularisation, and cortex-to-aorta enhancement index (CAEI). The radiologic and biometric (eg, donor weight) parameters were correlated with eGFR (CKD-EPI formula) change between baseline and at discharge. RESULTS: Donor weight was correlated with a loss of eGFR (P < .001). Kidney volumetric parameters including renal cortex and parenchyma volume, as well as renal artery cross-section area were associated with donor weight (r = 0.50 P < .001 and r = 0.39 P < .001). CAEI was correlated with a loss of eGFR (P = .003) and was related to the donor's sex in favor of men. Forty-one (37%) donors had an additional renal artery, which did not influence kidney function. No influence of cortical gaps or scarring on eGFR was observed. CONCLUSIONS: CAEI may be a helpful tool in predicting greater short-term kidney function decrease after living kidney donation. Male sex is the strongest risk factor of greater eGFR loss after kidney donation.

Computed tomographic angiography criteria in the diagnosis of brain death-comparison of sensitivity and interobserver reliability of different evaluation scales.

INTRODUCTION: The standardized diagnostic criteria for computed tomographic angiography (CTA) in diagnosis of brain death (BD) are not yet established. The aim of the study was to compare the sensitivity and interobserver agreement of the three previously used scales of CTA for the diagnosis of BD. METHODS: Eighty-two clinically brain-dead patients underwent CTA with a delay of 40 s after contrast injection. Catheter angiography was used as the reference standard. CTA results were assessed by two radiologists, and the diagnosis of BD was established according to 10-, 7-, and 4-point scales. RESULTS: Catheter angiography confirmed the diagnosis of BD in all cases. Opacification of certain cerebral vessels as indicator of BD was highly sensitive: cortical segments of the middle cerebral artery (96.3 %), the internal cerebral vein (98.8 %), and the great cerebral vein (98.8 %). Other vessels were less sensitive: the pericallosal artery (74.4 %), cortical segments of the posterior cerebral artery (79.3 %), and the basilar artery (82.9 %). The sensitivities of the 10-, 7-, and 4-point scales were 67.1, 74.4, and 96.3 %, respectively (p<0.001). Percentage interobserver agreement in diagnosis of BD reached 93 % for the 10-point scale, 89 % for the 7-point scale, and 95 % for the 4-point scale (p=0.37). CONCLUSIONS: In the application of CTA to the diagnosis of BD, reducing the assessment of vascular opacification scale from a 10- to a 4-point scale significantly increases the sensitivity and maintains high interobserver reliability.

Congenital bipartite atlas with hypodactyly in a dog: clinical, radiographic and CT findings.

A three-year-old Border collie was diagnosed with a bipartite atlas and bilateral forelimb hypodactyly. The dog showed signs of acute, non-progressive neck pain, general stiffness and right thoracic limb non-weight-bearing lameness. Computed tomography imaging revealed a bipartite atlas with abaxial vertical bone proliferation, which was the cause of the clinical signs. In addition, bilateral hypodactyly of the second and fifth digits was incidentally found. This report suggests that hypodactyly may be associated with atlas malformations.

Bidirectional modulation of isoflurane potency by intrathecal tetrodotoxin and veratridine in rats.

BACKGROUND AND PURPOSE: Results from several studies point to voltage-gated Na(+) channels as potential mediators of the immobility produced by inhaled anaesthetics. We hypothesized that the intrathecal administration of tetrodotoxin, a drug that blocks Na(+) channels, should enhance anaesthetic potency, and that concurrent administration of veratridine, a drug that augments Na(+) channel opening, should reverse the increase in potency. EXPERIMENTAL APPROACH: We measured the change in isoflurane potency for reducing movement in response to a painful stimulus as defined by MAC (minimum alveolar concentration of anaesthetic required to abolish movement in 50% of subjects) caused by intrathecal infusion of various concentrations of tetrodotoxin into the lumbothoracic subarachnoid space of rats, and the change in MAC caused by the administration of a fixed dose of tetrodotoxin plus various doses of intrathecal veratridine. KEY RESULTS: Intrathecal infusion of tetrodotoxin (0.078-0.63 microM) produced a reversible dose-related decrease in MAC, of more than 50% at the highest concentration. Intrathecal co-administration of veratridine (1.6-6.4 microM) reversed this decrease in a dose-related manner, with nearly complete reversal at the highest veratridine dose tested. CONCLUSIONS AND IMPLICATIONS: Intrathecal administration of tetrodotoxin increases isoflurane potency (decreases isoflurane MAC), and intrathecal administration of veratridine counteracts this effect in vivo. These findings are consistent with a role for voltage-gated Na(+) channel blockade in the immobility produced by inhaled anaesthetics.

Coil embolization of two flow-related aneurysms in p1 segment of the posterior cerebral artery in a patient with occlusion of the ipsilateral internal carotid artery.

Aneurysms of the posterior cerebral artery (PCA) are uncommon (about 1% of all intracranial aneurysms) and their neurosurgical treatment is associated with high operative risk. We report on two saccular aneurysms of the P1 segment of the right PCA, combined with occlusion of the C1 segment of the internal carotid artery (ICA) detected during routine diagnostic studies in a 58-year-old patient with slight sensory loss in the left extremities. The aneurysms were embolized during two consecutive sessions, without subsequent complications. Endovascular intervention is an efficient method in the treatment of multiple aneurysms in the P1 segment of the PCA.

The European Intra-Inter Theater Aeromedical Evacuation System:--our mission--our attempt.

The logistics of aeromedical evacuation are discussed. The order of magnitude of the problem and detailed analyses are presented. Examples are presented for patient transfer from point of injury in areas remote from hospitalization through successive installations to the hospital for extended treatment and convalescence.