A critical approach to gamma variate fit of radionuclide-angiography pulmonary histograms

Radionuclide-angiography (RNA_ left-to-right intracardiac-shunt quantification algorithms, based on the part-by-part fit technique and the use of a so-called gamma variate model function (GVF), were tested via simulation analysis using data obtained from normal subjects. A good bolus of radioindicator was obtained by administering it directly into the vena subclavia. Normal subjects were defined as those having pulmonary histograms (PH) with no visible distortion caused by a shunt. Pure, non-superimposed data on the downslope of the PH curves, which are lost in presence of a shunt, proved to be appropriate reference values for testing the accuracy of results of standard shunt quantification algorithms. A generalized four-parameter GVF was introduced in order to extend the flexibility of the model function. The use of the three-parametric GVF to reconstruct the downslope of the PH curve out of the upslope data proved to be inadequate. This reveals an evident source of error in algorithms that calculate the shunt contribution by fitting GVF parameters to so-called difference-curve data. It is concluded that the inherent restricted statistical weight of RNA data prevents accurate results being obtained from standard RNA-shunt-assessment algorithms.     

选择性动脉造影在不明原因的下消化道出血诊断中的价值探讨

目的 探讨选择性动脉造影和造影时机选择在不时原因下消化道出血诊断中的价值。方法 运用Seldinger技术对32例患者进行选择性肠系膜上、下动脉及其分支造影,其中少量出血患者17例,中至大量15例。首次出血3例,2次以上反复出血29例。结果 32例中28例发现病变（87.5%）,其中肿瘤性病变（n=15）非肿瘤性病变（n=13）,少理出血未见造影剂外溢征,中至大量出血中造影剂外溢征占33％。结论 选择性动脉造影检查下消化道出血是一种安全、有效的方法,在少量出血和出血间歇期仍有很大价值;造影显示病变部位更重要于显示出血征象。     

Multimodal management of ruptured cerebral micro-arteriovenous malformations: A retrospective series of 19 cases and a review of the literature

BackgroundMicro-arteriovenous malformations (micro-AVMs) are defined as AVMs just visible on angiography with a nidus size between 0.5 and 1 cm. Their principal manifestation is intracranial hemorrhage and their diagnosis and therapeutic management are still unclear.MethodsThe aim of our work was to show the clinical presentation, treatment and outcome of ruptured cerebral micro-AVMs in a retrospective cohort study of 19 patients and a systematic review of the literature.ResultsWe obtained a total of 20 micro-AVMs in 19 patients. The mean age was 47.3 years. Clinical presentation was acute bleeding. The mean volume of hematoma was 12.9 mm³ (0 - 60.4), with topographic distribution as follows: 64% cortical with supratentorial bleeding, 26% deep, and 10% in the posterior fossa. Among the 20 micro-AVMs of the series, 11 (55%) had endovascular management, 6 (30%) had surgical treatment and 3 (15%) had GK radiosurgery alone. All of our patients have been cured at the end of the follow up without re-permeabilization. In our series, clinical outcome showed good recovery with a mean score of 4.6 on Glasgow Outcome Scale (GOS). In the literature, 88% of patients had a GOS of 4 or 5.DiscussionIntracerebral hematoma (ICH) was the main clinical manifestation. In the case of negative initial angiographic assessment, patients must have supraselective angiographic exploration. In the case of conservative treatment of hematoma, endovascular obliteration and microsurgical exclusion seems to be reasonable therapeutic options, according to our observations.     

Treatment of Recurrent Hemarthrosis Following Total Knee Arthroplasty Using Surgical Interventions

BackgroudRecurrent hemarthrosis following total knee arthroplasty (TKA) is a rare complication. Its pathophysiology and standard treatments have not yet been established. In this study, we report 7 cases of recurrent hemarthrosis after TKA in which failure of the initial conservative treatment was followed by angiographic embolization; in 1 of the 7 cases, arthroscopic electrocauterization was also performed after treatment failure with selective embolization.MethodsFrom January 2015 to May 2018, 7 patients visited our hospital due to recurrent hemarthrosis after TKA. Their medical records and serologic test results were reviewed to check for the presence of any bleeding disorder and history of anticoagulant use. Implant malalignment and instability were checked using X-ray. In all cases, the conservative treatment failed, so interventional angiography with selective embolization was performed, which was also followed by arthroscopic electrocauterization if the outcome was unsatisfactory.ResultsThe interval between TKA and the onset of hemarthrosis ranged from 3 to 76 months (average, 34.1 months). There was no coagulopathy and instability. All patients underwent conservative treatment at an interval of 4.3 months and the rate of relapse was 3.1 on average. On the interventional angiography, 6 cases showed vascular blush, and 1 case had pulsatile bleeding. The average duration for interventional angiography was 90.9 minutes. The average length of follow-up was 38.8 months. Embolization was successfully performed in 4 cases. In 2 of 3 failed cases, the symptoms improved without further treatment. In the remaining 1 failed case, the patient had a relapse of hemarthrosis, so an arthroscopic procedure was performed, which led to identification of the suspicious bleeding point by using preoperative angiographic findings. Electrocauterization was performed and active bleeding was stopped. All cases with recurrent hemarthrosis achieved improvement.ConclusionsInterventional angiography was used to aid in the diagnosis of recurrent hemarthrosis, and therapeutic selective embolization provided satisfactory clinical results. Even if selective embolization fails, interventional angiography may be helpful for further surgical procedures because it reveals vascular blush of a bleeding site. Therefore, interventional angiography and selective embolization should be considered to be a useful treatment for recurrent hemarthrosis after TKA.     

The arterial blood supply of the pancreas: a review III. The inferior pancreaticoduodenal artery

Summary This article is the third part of a comprehensive review on the pancreatic arterial blood supply and deals with the inferior pancreaticoducdenal a. The aim of this review is to summarise the anatomical studies, starting from Haller's reports, and to supply as far as possible, with original material, angiographic evidences for the classic anatomical notions. For this purpose, the overall research was carried out by picking out and studying 1015 selective angiographies (celiac trunk and its branches, superior mesenteric a.) taken from the angiographic archives of the Institutes of Radiology of Siena, Rome (Catholic University), and Perugia. Angiographically, the authors observed the inferior pancreaticoduodenal a., present in most instances, as arising from the superior mesenteric a., from the right accessory hepatic a., or from a common trunk with the first or the first two jejunal aa. Some variations of the course have been shown. The authors underline and discuss the discordant opinions still existing regarding the incidence of the different ways the inferior pancreaticoduodenal a. arises and the surgical importance of the variation of origin of this artery.

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La vascularisation artérielle du pancréas : une mise au point. III. L'artère pancréatico-duodénale inférieure

Résumé Cet article est la troisième partie d'une étude détaillée de la vascularisation artérielle du pancréas et traite de l'a. pancréatico-duodénale inférieure. Le but de ce travail est de résumer les études anatomiques, depuis la publication de Haller, et de fournir autant qu'il est possible, avec un matériel original, les preuves angiographiques des notions anatomiques classiques. Pour cela, la recherche complète a été menée sur le choix et l'ðude de 1015 angiographies sélectives (tronc coeliaque et ses branches, a. mésentérique supérieure) tirées des archives angiographiques des instituts de radiologie de Sienne, Rome (université catholique) et Pérouse. Sur les angiographies les auteurs ont observé l'a. pancréatico-duodénale inférieure, présente dans la plupart des cas, naissant de l'a. mésentérique supérieure, de l'a. hépatique droite accessoire, ou d'un tronc commun avec la première ou les deux premières aa. jéjunales. Quelques variantes ont été montrées dans son trajet. Les auteurs soulignent et discutent les opinions encore divergentes sur la fréquence des différentes origines de l'a. pancréatico-duodénale inférieure et sur leur importance chirurgicale.

     

Post-mortem cast angiography in the diagnostics of graft complications in patients with fatal outcome following coronary artery bypass grafting (CABG)

The advantages and limitations of a novel post-mortem angiographic method using solidifying silicone rubber and lead oxide as a contrast medium in detecting coronary artery graft complications on a routine basis were evaluated in a series of 223 consecutive patients with fatal outcome within 30 days following coronary artery bypass grafting (CABG). Of these patients, 166 (74.4%) were male and 57 (25.6%) female (mean age 61.9 ± 9). Coronary grafts totalled 660 (3.0 per patient) with 517 aortic and 838 coronary anastomoses. At autopsy, the rubber cast model of the grafts and coronary arterial tree was exposed by a bend scalpel and sites of possible complications were examined. Post-mortem angiographs were re-evaluated and compared with preoperative angiographs and dissection findings. By combining the findings of angiography and heart dissection, 122 (54.7%) of the 223 patients were found to have some type of complication of the graft or the anastomosis. The diagnostic sensitivity and specificity of postmortem angiography was 100% in assessing narrowing or twisting of the graft as well as narrowing of the aortal anastomosis, whereas these findings were revealed with difficulty by autopsy dissection only. In cases with correct x-ray projection, narrowing and occlusion of the proximal aortal and distal coronary anastomosis were also reliably revealed by angiography. In contrast, graft thrombosis was clearly overdiagnosed by angiography, leading to a lower specificity (84%) but high sensitivity (100%) in detecting this complication. Post-mortem angiography also failed to detect dissection of the wall of the graft or anastomosis. Technical problems with this angiographic method were due to too low perfusion pressure, too rapid polymerizing of the silicone rubber, leakage of contrast medium into the ventricles, or faulty x-ray projections. These results suggest that our post-mortem angiographic technique, yielding a permanent rubber- cast model of the graft and anastomosis site, improves the accuracy of diagnostics of postoperative CABG complications and eases postoperative autopsy dissection, which can now be directed to confirm suspected complications. Received: 27 October 1997 / Received in revised form: 2 July 1998     

Cerebral reperfusion in brain death of a newborn. Case report

A case of sudden infant death after 15 minutes of successful resusciation of cardiovascular function is presented. While apnoic cranial nerve areflexia and electrocerebral silence persisted, angiography and transcranial Doppler sonography demonstrated nearly normal cerebral perfusion, which even increased day by day inspite of the persistence of other signs of brain death. The phenomenon cerebral reperfusion is concluded to be compatible with the diagnosis of brain death.     

Hyperdense middle cerebral artery CT sign

Summary The early CT finding of an hyperdensity of a portion of the middle cerebral artery Hyperdense Middle Cerebral Artery Sign (HMCAS), in patients with supratentorial stroke, is often indicative of an embolic occlusion. Aim of this study was to verify the incidence and reliability of the HMCAS and its possible correlation with early CT findings and with the extent of late brain damage. We studied 36 patients presenting with symptoms of stroke in the MCA territory, by means of CT and angiography performed respectively within 4 and 6 hours. Follow-up CT scans were then obtained after one week and three months from the ischemic event. The HMCAS was present in 50% of our patients and in this group it always correlated positively with the angiographic finding of occlusion. The same group presented a high incidence of erly CT hypodensity (88%). Finally the presence of HMCAS might be considered a negative prognostic sign for the development of extensive brain damage.     

A ruptured dissecting aneurysm of the anterior radiculomedullary artery caused by vertebral angiography

We report here a 54-year-old man with an aneurysm arising on a cervical anterior radiculomedullary artery. The aneurysm ruptured just after vertebral angiography for a vascular anomaly of the brain, and it appeared to be fusiform, with thrombosis following angiography. Considering the sequential radiological studies and clinical course, it was assumed to be a dissecting aneurysm caused by the angiography. MRI showed severe swelling of the cervical spinal cord and an infarct in the territory of the anterior spinal artery. The mechanism of this rare complication is discussed. Received: 29 March 1999 Accepted: 18 August 1999     

冠状动脉MSCT成像技术探讨

目的探讨回顾性心电门控技术在MSCT冠状动脉成像中的应用。方法15例患者做MSCT冠状动脉成像检查,采用回顾性心电门控和心脏分段重建算法,选择0.5s螺旋扫描。在9个R-Rinterval上进行冠状动脉CT图像重建。结果15例患者的230个冠状动脉节段(内径>2mm)中,213个节段(91%)在70%R-Rinterval上显示最好,15(6.4)、9(3.8%)和3(1.3%)个节段分别在80%、40%和50%R-Rinterval上显示最好。结论冠状动脉通常在心动周期R波后70%R-Rinterval上显示最好。