Negative Digital Subtraction Research Articles

Abstract 240: Diagnostic Value of Catheter Angiography and Magnetic Resonance Imaging in Perimesencephalic and Non‐Perimesencephalic Subarachnoid Hemorrhage: A Retrospective Analysis

Introduction/Purpose Spontaneous subarachnoid hemorrhage (SAH) without a structural source can be seen in up to 15% of all spontaneous SAH, which includes diffuse non‐aneurysmal SAH, sulcal SAH and perimesencephalic (PM) SAH. Although catheter angiography is considered the gold standard to exclude a vascular etiology, multiple studies suggest that computed tomography angiography (CTA) is adequate in PMSAH and magnetic resonance imaging (MRI) does not produce additional benefit. Without clear recommendations, practice patterns regarding the diagnostic management of these patients remain variable throughout the country. The aim of this study was to evaluate the diagnostic value of MRI and catheter angiography in perimesencephalic (PM) and nonperimesencephalic (non‐PM) subarachnoid hemorrhage (SAH) of unknown origin. Materials and Methods: We conducted a retrospective study of all patients with spontaneous SAH between January 2021 and July 2023. Included in the study were cases of spontaneous SAH diagnosed with CT with an initial negative digital subtraction angiogram (DSA). Additionally, patients who had a positive finding for a vascular source of hemorrhage such as an aneurysm, arteriovenous malformation (AVM) or dural arteriovenous fistula (dAVF) on DSA with a negative CTA or a CT with a PMSAH bleeding pattern were included for comparison. The number and types of follow‐up imaging studies were recorded. Results 420 patients with spontaneous SAH were screened, in which 101 patients met study criteria. 86 patients were found to have a negative DSA, of which 51 (59.3%) were found to have a PMSAH bleeding pattern. Follow‐up MR performed within one week of presentation demonstrated no source of hemorrhage in any of the patients with PMSAH, however, within the subgroup of diffuse‐non‐aneurysmal SAH, two patients (5.7%) were found to have a cavernoma on MRI (p=0.039). Among the 226 patients (53.8%) who had a positive DSA in the same time period, nine patients (3.9%) had a negative CTA and 10 patients (4.4%) had a PMSAH hemorrhage pattern. Conclusion In spite of a well‐established hemorrhagic pattern for aneurysmal SAH, aneurysms may still present with a perimesencephalic SAH distribution. In light of our institutional experience, CTA is not deemed adequate alone for the exclusion of aneurysms in PMSAH, where catheter angiography should still be considered the gold standard in diagnostic evaluation. Finally, MRI of the brain and craniocervical region did not produce any benefit for the detection of a vascular etiology in PMSAH, however, the utilization of MRI should be considered for rare bleeding sources in non‐PM SAH, particularly when intraparenchymal hemorrhage is also present.

Delayed appearance of basilar trunk small atypical aneurysms in nontraumatic, initially angiogram-negative subarachnoid hemorrhage: A report of three patients.

Repeat angiography will identify vascular pathology in approximately 10% of cases following angiogram-negative subarachnoid hemorrhage (anSAH), but small atypical aneurysms of the basilar artery are very uncommon. To report a case series of delayed appearance of nontraumatic basilar artery small atypical aneurysms. IRB approval was obtained for this retrospective case series and patient consent was waived. Herein we report three cases of spontaneous anSAH, all of whom had a negative digital subtraction angiogram (DSA) on admission and all of whom had appearance of a small atypical aneurysms of the upper basilar trunk/apex on follow-up imaging (two during the initial admission and one in a delayed fashion). All three patients were ultimately treated with flow diversion (although one patient underwent attempted coiling that was abandoned due to inability to catheterize the aneurysm). This report highlights the importance of a repeat DSA in cases of anSAH as well as the importance of scrutinizing the basilar trunk for these very small atypical aneurysms that may go unnoticed.

Familial Predisposition and Differences in Radiographic Patterns in Spontaneous Nonaneurysmal Subarachnoid Hemorrhage.

Subarachnoid hemorrhage (SAH) from an intracranial aneurysmal rupture is the most common nontraumatic etiology for SAH, but up to 15% of patients with SAH have no identifiable source. To assess familial predisposition to spontaneous nonaneurysmal SAH (naSAH) and to evaluate whether family history affects the severity of presentation and prognosis of this condition. We conducted a retrospective analysis of all spontaneous SAH with negative digital subtraction angiography from 2004 to 2018. Patients were divided into 2 groups: patients with first- or second-degree relatives with intracranial aneurysms and patients with no family history. Univariate and multivariate regression analyses were used to study patient presentation, radiographic patterns of hemorrhage, and clinical outcome. A total of 100 patients met the inclusion criteria. There were no individuals with family history of naSAH. A total of 15 patients (15%) had at least one family member with an intracranial aneurysm, of which 12 (12%) presented as SAH. Patients without family history had a higher percentage of perimesencephalic presentation, whereas those with family history had a higher percentage of nonperimesencephalic SAH presentation (47%vs 13%, odds ratio [OR] 0.17 [95% CI 0.04, 0.81]). We found a high rate of family history of intracranial aneurysms in patients who presented with naSAH. Although there was no difference in clinical outcome in patients with and without family history, there appears to be a higher percentage of nonperimesencephalic radiographic patterns of SAH in those with family history, suggesting possible different etiologies of these hemorrhages.

Non-traumatic non-aneurysmal subarachnoid haemorrhage: Single institutional experience

Aim: Despite the advanced diagnostic methods we use today, the rate of negative digital subtraction angiography (DSA) is 15% in patients diagnosed with subarachnoidal hemorrhage (SAH), and these types of hemorrhages are named as non-aneurysmal (NASAH). Various factors such as inadequate interpretation of the beginning angiography, vasospasm, thrombosis, intra-cerebral hematoma pressure may cause DSA to be negative. This study aims to determine the causes of bleeding in patients who were suffered from NASAH.Materials and Methods: The study evaluated 664 patients with SAH from 2010 to 2016. DSA was performed on these patients within the first 3 or 6 hours. Sixty-seven patients with DSA negative were included in the study group. The patients were divided into three groups as perimesencephalic subarachnoidal hemorrhage (PMSAH), non-perimesencephalic subarachnoidal hemorrhage (nPMSAH), CT negative subarachnoidal hemorrhage (CT negative SAH). These three groups were evaluated based on age, gender, Glascow coma scale (GCS), World Federation of Neurosurgical Societies (WFNS) grade, Hunt and Hess Classification and Fisher’s scale, hospitalization time duration, complications and computerized tomography (CT), and cervical and cranial MRI was performed on patients without correlation between DSA results if needed.Results: Of the 664 patients diagnosed with SAH, 67 (10.09%) had NASAH. Statistically significant differences were found between CT Negative SAH and PMSAH and CT Negative SAH and nPMSAH in terms of the variables of GCS during hospital admission and total duration of hospitalization. Statistically significant differences were found between CT Negative SAH and PMSAH and nPMSAH in terms of the variables of GCS during hospital discharge. There were statistically significant differences between the types in terms of WFNS Classification, Hunt and Hess Classification and Fisher’s Scala.Conclusion: We believe that this study will contribute to the literature about the necessity of performing additional radiologic imaging during clinical follow-up since belated diagnosis in patients with NASAH may increase mortality.

Empiric cone-beam CT-guided embolization in acute lower gastrointestinal bleeding.

To evaluate the clinical effect and safety of cone-beam CT (CBCT)-guided empirical embolization for acute lower gastrointestinal bleeding (LGIB) in patients with a positive CT angiography (CTA) but subsequent negative digital subtraction angiography (DSA). A retrospective study of consecutive LGIB patients with a positive CTA who received a DSA within 24h from January 2008 to July 2019. Patients with a positive DSA were treated with targeted embolization (TE group). Patients with a negative DSA underwent an empiric CBCT-guided embolization of the assumed ruptured vas rectum (EE group) or no embolization (NE group). Recurrent bleeding, major ischemic complications, and in-hospital mortality were compared by means of Fisher's exact test. Further subgroup analysis was performed on hemodynamic instability. Eighty-five patients (67.6years ± 15.7, 52 men) were included (TE group, n = 47; EE group, n = 19; NE group, n= 19). If DSA was positive, technical success of targeted embolization was 100% (47/47). If DSA was negative and the intention to treat by empiric CBCT-guided embolization, technical success was 100% (19/19). Recurrent bleeding rates in the TE group, EE group, and NE group were 17.0% (8/47), 21.1% (4/19), and 52.6% (10/19) respectively. Empiric CBCT-guided embolization reduced rebleeding significantly in patients with a negative DSA and hemodynamic instability (EE group, 3/10 vs NE group, 10/12, p = .027). Major ischemic complications occurred in one patient (TE group). Overall, the in-hospital mortality rate was 7.1% (6/85). Empiric cone-beam CT-guided embolization proved to be a feasible, effective, and safe treatment strategy to reduce rebleeding and improve clinical success in hemodynamically unstable patients with acute LGIB, positive CTA but negative DSA. • A novel transarterial embolization technique guided by cone-beam CT could be developed extending the "empiric" embolization strategy to lower gastrointestinal bleeding. • By implementing the empiric treatment strategy, nearly all patients with an active lower gastrointestinal bleeding on CTA will be eligible for a superselective empiric embolization, even if subsequent catheter angiography is negative. • In patients with a negative catheter angiography, empiric embolization reduces the rebleeding rate and, particularly in hemodynamically unstable patients, improves clinical success compared with a conservative "wait-and-see" management.

Analysis of negative DSA findings in patients with acute nonvariceal gastrointestinal bleeding: A retrospective study of 133 patients

PurposeTo analyze causes of acute nonvariceal gastrointestinal bleeding (GIB) with negative digital subtraction angiography (DSA) results. Materials and methodsThe clinical and follow-up data of 133 patients - recruited between February 2008 and November 2016 - with acute nonvariceal GIB and negative DSA results were included in this study. DSA results, diagnoses, and clinical outcomes were recorded. ResultsThe DSA results were negative in all 133 patients. Of the total, 55 patients (41.4%) chose to undergo surgery and 78 (58.6%) opted for conservative treatment. Within 30 days, there was no significant difference in the rebleeding or mortality rates between the two groups (P < .05). Of all 133 patients, 76 (57.1%) had upper GIB and 57 (42.9%) had lower GIB; within 30 days, the rebleeding rate in the upper GIB group (44.7%, 34/76) was significantly higher than that in the lower GIB group (26.3%, 15/57). There was no significant statistical difference (P < .05) within 30 days in the mortality rates between the two groups.Among patients with upper GIB, 26 (34.2%, 26/76) opted to undergo surgery and 50 (65.8%, 50/76) chose conservative treatment; within 30 days, the rebleeding rate in the group that chose surgery (61.5%, 16/26) was higher than that in the conservative treatment group (36%, 18/50). There was no significant difference (P < .05) within 30 days in the mortality rate between the two groups.Among the patients with lower GIB, 29 (50.9%, 29/57) chose to undergo surgery and 28 (49.1%, 28/57) opted for conservative treatment. Within 30 days, the rebleeding rate in the surgery group (13.8%, 4/29) was lower than that in conservative treatment group (39.3%, 11/28). There was no significant difference (P < .05) within 30 days in the mortality rate between the two groups.Sixteen patients underwent prophylactic arterial embolization; in 6 of these, bleeding was stopped for 30 days. DSA was then repeated in these 16 patients after a median interval of 1 day, and a positive bleeding site was found in 9 of the 16. Causes of bleeding were found in 111 patients by surgery or endoscopy, whereas the causes remained unknown in 22 patients. ConclusionsUpper GIB with negative DSA results was stopped by conservative treatment, whereas lower GIB required surgery to detect the culprit bleeding site. Rare causes of GIB should be considered and appropriate management selected in a timely manner in order to detect unusual causes.

MRI-detection rate and incidence of lumbar bleeding sources in 190 patients with non-aneurysmal SAH.

BackgroundUp to 15% of all spontaneous subarachnoid hemorrhages (SAH) have a non-aneurysmal SAH (NASAH). The evaluation of SAH patients with negative digital subtraction angiography (DSA) is sometimes a diagnostic challenge. Our goal in this study was to reassess the yield of standard MR-imaging of the complete spinal axis to rule out spinal bleeding sources in patients with NASAH.MethodsWe retrospectively analyzed the spinal MRI findings in 190 patients with spontaneous NASAH, containing perimesencephalic (PM) and non-perimesencephalic (NPM) SAH, diagnosed by computer tomography (CT) and/or lumbar puncture (LP), and negative 2nd DSA.Results190 NASAH patients were included in the study, divided into PM-SAH (n = 87; 46%) and NPM-SAH (n = 103; 54%). Overall, 23 (22%) patients had a CT negative SAH, diagnosed by positive LP. MR-imaging of the spinal axis detected two patients with lumbar ependymoma (n = 2; 1,05%). Both patients complained of radicular sciatic pain. The detection rate raised up to 25%, if only patients with radicular sciatic pain received an MRI.ConclusionRoutine radiological investigation of the complete spinal axis in NASAH patients is expensive and can not be recommended for standard procedure. However, patients with clinical signs of low-back/sciatic pain should be worked up for a spinal pathology.

Quadrigeminal perimesencephalic subarachnoid hemorrhage

ObjectiveA variant of perimesencephalic subarachnoid hemorrhage (PSAH) has been described characterized by blood centered in the quadrigeminal cistern and limited to the superior vermian and perimesencephalic cisterns. Herein, three cases of quadrigeminal PSAH are presented. Materials and methodsMedical records of all patients who underwent digital subtraction angiography for evaluation of non-traumatic SAH between July 2002 and April 2012 were reviewed. Patients with anterior circulation aneurysms were excluded. Two blinded reviewers identified admission noncontrast CT scans with pretruncal and quadrigeminal patterns of PSAH. ResultsThe total cohort included 106 patients: 53% (56/106) with one or more negative digital subtraction angiograms and 47% (50/106) with posterior circulation or posterior communicating artery aneurysms. Three patients with quadrigeminal PSAH were identified, two with nonaneurysmal SAH and one with a posterior circulation aneurysm. Seventeen patients (16%; 17/106) with pretruncal PSAH were identified, none of whom were found to have an aneurysm. The quadrigeminal pattern comprised 11% (2/19) of cases of pretruncal or quadrigeminal nonaneurysmal PSAH. ConclusionA small subset of patients with nonaneurysmal PSAH present with blood centered in the quadrigeminal cistern, and the etiology of this pattern may be similar to that of the classic pretruncal variant. However, patients with quadrigeminal PSAH must still undergo thorough vascular imaging, including at least two digital subtraction angiograms, to exclude a ruptured aneurysm.

Clinical effects of preventive interventional therapy in gastrointestinal bleeding patients with negative digital subtraction angiography findings

Clinical effects of preventive interventional therapy in gastrointestinal bleeding patients with negative digital subtraction angiography findings

The clinical characteristics of cognitive impairments in subarachnoid hemorrhage patients with negative digital subtraction angiography

Objective To estimate the cognitive function of subarachnoid hemorrhage patients with negative digital subtraction angiography (DSA), and analyse its relevant factors and clinical characteristics. Methods 96 subarachnoid hemorrhage patients were selected, and the disease condition were classfied into different grades by Fisher scale, Hunt-Hess scale and the cognitive function were estimated by mini-mental state examination(MMSE), then calculated its incidence, analysed the relationship between the classification and cognitive impairments. Results The incidences of cognitive impairment in subarachnoid hemorrhage patients with negative DSA were 51.04%. Cognitive impairment was closely related to Hunt-Hess and Fisher grade (P<0.01). Conclusion Subarachnoid hemorrhage patients with negative DSA exist different extent of cognitive impairment.The higher Hunt-Hess or Fisher grade, the more serious cognitive impairment. Key words: Subarachnoid hemorrhage; Cognitive impairment; Digital subtraction angiography

Contrast Extravasation on Computed Tomographic Angiography Mimicking a Basilar Artery Aneurysm in Angiogram-Negative Subarachnoid Hemorrhage

Contrast extravasation on computed tomography angiography (CTA) is becoming more common, with increasing use of CTA for myriad intracranial vascular pathologies. This article describes the first 2 documented cases of contrast extravasation from a nonaneurysmal basilar artery source seen on CTA and discusses possible pathophysiologic mechanisms. We present 2 cases of diffuse atraumatic subarachnoid hemorrhage in which the CTA showed an abnormality in association with the basilar artery highly suggestive of a ruptured aneurysm. Follow-up digital subtraction angiography, however, was completely negative. Subsequent repeat digital subtraction angiography failed to reveal a vascular lesion. Both patients were treated for complications associated with SAH, but given the negative digital subtraction angiography, no intervention was performed. Because of the frequent use of CTA, contrast extravasation is an increasingly common observation. Physicians should be aware that basilar artery extravasation can mimic the appearance of an aneurysm.

Diagnostic value of magnetic resonance imaging in perimesencephalic and nonperimesencephalic subarachnoid hemorrhage of unknown origin

The aim of this study was to evaluate the diagnostic value of MR imaging in perimesencephalic (PM) and nonperimesencephalic (non-PM) subarachnoid hemorrhage (SAH) of unknown origin. The authors conducted a retrospective review of all patients with SAH (1226 patients) in their department between January 1991 and December 2008. Included in the study were cases of spontaneous SAH diagnosed using CT scans obtained within 24 hours of the initial symptoms and initially negative digital subtraction (DS) angiograms. Patients with traumatic SAH and an unknown history were excluded from the study. Patients with initially negative DS angiograms were divided into 2 groups: Group 1, a typically PM bleeding pattern (PM SAH); and Group 2, a non-PM bleeding pattern (non-PM SAH) such as hemorrhage in the sylvian or interhemispheric fissure. Cranial MR imaging including the craniocervical region was performed within 72 hours after SAH was diagnosed in all patients in Groups 1 and 2. One thousand sixty-eight patients underwent DS angiography, and among them were 179 (16.7%) with negative angiograms--47 patients (26.3%) from Group 1 and 132 patients (73.7%) from Group 2. Magnetic resonance imaging demonstrated no bleeding sources in any case (100% negative). Thirty-four patients in Group 1 and 120 patients in Group 2 underwent a second DS angiography study. Digital subtraction angiography revealed an aneurysm as the bleeding source in 1 case in Group 1 and in 13 cases in Group 2. Magnetic resonance imaging of the brain and craniocervical region did not produce additional benefit for the detection of a bleeding source and the therapy administered for PM SAH and non-PM SAH (100% negative). The costs of this examination exceeded the clinical value. Despite the results of this study, MR imaging should be discussed on a case-by-case basis because rare bleeding sources are periodically diagnosed in cases of non-PM SAH. A second-look DS angiogram is necessary because aneurysmal hemorrhage occasionally produces PM SAH as well as non-PM SAH. Further prospective studies are needed to verify the authors' results in the future.

Active extravasation of the abdomen and pelvis in trauma using 64MDCT

The objective of this study was to determine the clinical and management implications of the finding of active extravasation in blunt or penetrating trauma patients evaluated with abdomino-pelvic computed tomography (CT) using 64MDCT technology. This HIPAA compliant, retrospective study was IRB-approved, and the need for consent was waived. All adult patients scanned with 64MDCT who sustained blunt or penetrating abdomino-pelvic trauma and had findings of active extravasation at our Level I trauma center during a 30-month period were included. Two radiologists reviewed all abdomino-pelvic CT scans and characterized the active hemorrhage by location, extent, and attenuation on all available phases of imaging. Subsequent therapy and disposition were determined by reviewing the patients' medical records. The relationship between the location of a source of extravasation and subsequent clinical outcome was evaluated using Fischer's exact test. The relationship between the size and attenuation of the active hemorrhage and patient outcome were compared using the Wilcoxon rank sum test. One hundred and twenty-five patients with active extravasation were included. Patients with solid organ or pelvic injuries that were managed conservatively or had a negative digital subtraction angiogram had statistically significant smaller areas of active extravasation when compared to those that required intervention or died. When the attenuation values of extravasation are normalized to the intravascular attenuation achieved after intravenous contrast injection, no significant differences were seen based on subsequent clinical outcome. Based on location, those patients with solid organ, gastrointestinal/mesenteric, and pelvic sources of bleeding showed statistically significant higher likelihood of requiring subsequent intervention or dying, compared with those patients with subcutaneous, intramuscular, or retroperitoneal sources of active extravasation who were more likely to be managed conservatively (p < 0.0001, p = 0.005, p = 0.006, respectively). In blunt and penetrating trauma patients evaluated using 64MDCT technology, the location and size of the region of active extravasation are predictive of the type of subsequent clinical management. Normalized attenuation values of the active extravasation, however, are not predictive of subsequent management.

Supplementary Use of Computed Tomographic Angiography in Subarachnoid Hemorrhage with Negative Digital Subtraction Angiography: Report of a Case

With advances of resolution and re-combination techniques in computed tomography (CT), CT angiography (CTA) has frequently been employed to detect intracranial aneurysms. Its advantages, such as being non-invasive and time efficient, as well as the high resolution and 3-dimensional images obtained, have made it the preferred choice for screening patients at high-risk for intracranial aneurysms. Here we report the case of a 57-year-old man whose initial digital subtraction angiography (DSA) was negative. However, a follow-up CTA revealed a neck of intracranial aneurysm on the anterior communicating artery 48 hours later. This aneurysm was clipped successfully through the left sub-frontal approach and the patient made a good recovery following the surgery. In this case, a DSA-missed aneurysm was picked up by CTA and a catastrophe was prevented. We have thus shown DSA-negative pictures in CTA-positive subarachnoid hemorrhage, and the reason for this unusual image presentation was probably intra-aneurysmal thrombosis, which was confirmed by surgery.

Clinical Follow-Up of Patients after a Negative Digital Subtraction Pulmonary Arteriogram in the Evaluation of Pulmonary Embolism

This study was designed to examine the clinical course of patients following digital subtraction pulmonary arteriography (DSPA) interpreted as negative for pulmonary emboli (PE). Sixty-three patients underwent DSPA interpreted as negative for PE over a 27-month period. Follow-up data were collected by means of medical and diagnostic radiology record review, interviews of referring physicians, and patient telephone interviews. Of 63 patients, two were excluded and seven were lost to follow-up, leaving a study population of 54 patients. Mean follow-up was 12.1 months (range, 0-28.5 months). Thirty-one reported no symptoms of PE. Of 13 patients reporting intermittent chest pain and/or dyspnea during their mean follow-up of 13.6 months, 10 had a history of cardiac, nonthrombotic pulmonary, or gastroesophageal reflux disease. There were no subsequent positive angiograms or ventilation/perfusion scans. Comorbid conditions in the 10 patients who died included cardiac events (n = 4), advanced cancer (n = 2), sepsis/pneumonia (n = 2), sarcoidosis (n = 1), and cerebrovascular accident (n = 1). No documented PE was identified. The technique of DSPA is sufficiently sensitive to exclude clinically significant PE. The advantages of image post-processing, in addition to the savings in cost, time, and contrast media, support its use in the angiographic diagnosis of PE.