The outcome of closure of inguinal hernia with laparoscopic percutaneous extraperitoneal closure in young adults.

BACKGROUND: Hernioplasty is one of the most commonly performed surgeries. However, the optimal procedure for young adults has not been defined yet. Our study compared the outcomes of laparoscopic percutaneous extraperitoneal closure (LPEC) in young adults with outcomes in children. MATERIAL AND METHODS: We retrospectively reviewed patients aged 0-30 years who underwent LPEC. Data regarding age, sex, hernia type, surgical time, pre-intraoperative laterality, contralateral patent processus vaginalis (CPPV), and complications were analyzed. RESULTS: LPEC was performed on 2642 patients in our hospital. Of these, 51 patients were young adults (aged 15-30 years). Asymptomatic CPPV in unilateral patients was frequent in the <15-year age group (50.2%) compared to the 15-30-year age group (15.9%). The median surgical time was shorter in the <15-year age group (19 min, interquartile range [IQR]: 24-33) compared to that of the 15-30-year age group (33 min, IQR: 23.3-40.8). CONCLUSIONS: This is the first report on the outcomes in young adult patients who underwent LPEC. The median surgical time was longer in the 15-30-year age group than in the <15-year age group. The median follow-up was 4.7 years with no intra-postoperative complications, such as postoperative bleeding, infection, persistent pain, and recurrence. LPEC is an effective, cosmetic, and safe surgical treatment in young adults and children.

[Giant Thrombus in the Left Atrium Showing a Rapid Growth:Report of a Case].

A 74-year-old woman had been on hemodialysis for about 2 months using a short-term indwelling dialysis catheter due to chronic kidney disease. A 20 mm-diameter left atrial neoplastic lesion was noted during a screening echocardiogram performed at the time of induction of hemodialysis. The lesion rapidly increased to 30 mm 2 months later and was referred to our hospital for surgical resection. Under cardiopulmonary bypass and cardiac arrest, tumor resection was performed. Although the lesion was myxomatous with a thin stalk on the left atrial ceiling, the pathological diagnosis was thrombus. After the initiation of anticoagulation, the patient was discharged.

Evaluation of the widths of the mucosal strips in pathological examination of specimens of endoscopic submucosal dissection for early gastric cancer.

BACKGROUND: Endoscopic submucosal dissection (ESD) is the standard treatment for early gastric cancer in Japan. Pathological evaluation of ESD specimens is considered essential to determine if additional gastrectomy is necessary. Usually, specimens resected by ESD are sliced into 2-3 mm wide sections, and each section is examined for depth of tumor and lymphovascular invasion. Nevertheless, in most cases of additional gastrectomy, lymph node metastasis is not present. Given that there are few-studies on how clinical-decisions based on the pathologic-evaluation-method, in particular the specimen cut-width, influence patient outcomes, we retrospectively evaluated whether reducing the number of cuts to one-half or one-third would result in underestimation of the real need for additional surgery. The effect of the actual cut-width on recommended treatment (referral to operation) and patient-outcomes was also assessed. METHODS: Pathological records of 498 lesions from 439 patients were reviewed and re-evaluated. All pathological descriptions are based on the gastric cancer classification system of the Japanese Gastric Cancer Association, 15th edition. RESULTS: In 5.8% and 8.5% of the total specimens, underdiagnosis of tumor-depth and lymphovascular invasion occurred when the number of sections was reduced to one-half and one-third, respectively. Significantly more submucosal invasions were found in the group in which the cut-with was between 3 and 4 mm than in the group in which the cut width was less than 3 mm. CONCLUSION: Evaluation of the appropriate cut-width is important and should be discussed from the standpoint of labor costs and lost opportunities to search for molecular markers in ESD materials.

[Requiring Differential Diagnosis of Pulmonary Arteriovenous Fistula and Pulmonary Venous Aneurysm: Report of a Case].

A pulmonary arteriovenous fistula (PAVF) is a direct abnormal connection between the pulmonary artery and pulmonary vein, lacking capillary tissue. On the other hand, a pulmonary venous aneurysm (PVA) is a localized dilation and aneurysmal formation in the pulmonary vein without reflux issues. Treatment approaches for PAVF and PVA differ, considering surgery or catheter embolization for PAVF due to the risk of cerebral infarction or rupture caused by the abnormal shunt. PVA cases, being rare in rupture and embolism, are usually recommended for observation. Therefore, distinguishing between these two conditions is crucial. This article presents a case where both PVA and PAVF were present, necessitating a differential diagnosis.

Computed tomography perfusion in patients of stroke with left ventricular assist device.

Left ventricular assist devices (LVAD) are widely applied for patients with severe heart failure as a bridge to heart transplantation as well as destination therapy. Patients with implanted LVAD have an increased risk of cerebral thrombosis and computed tomographic perfusion (CTP) has the potential to be performed for early diagnosis and treatment of acute ischemic stroke (AIS), including interventional thrombectomy. Here, we report our series of CTP examination in patients having suspected AIS after LVAD implantation. We retrospectively investigated 33 contrast-enhanced CTPs from January 2017 to December 2018 which were performed in 12 cases of patients because of possible neurological findings leading to suspected AIS during LVAD circulatory support who did not have definite ischemic findings nor intracerebral hemorrhage on non-contrast computed tomography. AIS with perfusion disturbance area was diagnosed in 11 (33.3%) out of a total of 33 CTPs in 4 (33.3%) out of 12 patients. Endovascular thrombectomy (EVT) was successfully performed in this research study four times for three patients. CTP was able to detect and determine the indication for EVT without serious complications. CTP could potentially be the first-choice assessment for early diagnosis of AIS with recoverable ischemic penumbra in patients with LVAD implantation.

Technique and Theory of Hollow-fiber Phantom for Cerebral CT Perfusion.

We developed a phantom using a hollow-fiber hemodialyzer to evaluate the quantitative reliability of cerebral computed tomography (CT) perfusion. Our phantom consisted of a hollow-fiber hemodialyzer and a syringe-shaped X-ray device made up of resin. The phantom can give theoretical true values for cerebral blood volume, cerebral blood flow, and mean transit time. We compared the values measured in the phantom with predicted theoretical values. The purpose of the current report is to describe the theory and experimental technique used to obtain an absolute value in a phantom.

Diffusion-weighted MR imaging of pancreatic cancer and inflammation: Prognostic significance of pancreatic inflammation in pancreatic cancer patients.

BACKGROUND: Pancreatic cancer often accompanies chronic obstructive pancreatitis (COP) due to obstruction of the main pancreatic duct, and the inflammatory environment may enhance cancer progression. The purpose of this study is to evaluate COP using the apparent diffusion coefficient (ADC) value measured by diffusion-weighted MR imaging (DWI), and to assess its prognostic significance in pancreatic cancer. METHODS: Twenty-eight patients (16 men, 12 women; mean age 67.1 years) with pancreatic cancers who underwent DWI followed by curative surgery were evaluated. The ADC value of pancreatic parenchyma upstream to the tumor (upstream pancreas) was measured and compared with the upstream pancreatic duct dilatation to assess whether DWI could reflect COP. The ADC values of tumor and upstream portion were compared with overall survival (OS) using Cox regression and Kaplan-Meier analysis. RESULTS: The ADC value of upstream pancreas was significantly lower in patients with greater dilated pancreatic duct than those with less (P = 0.03). In univariate Cox regression analysis, the ADC value of upstream pancreas showed a significant association with OS (P = 0.01), but that of tumor did not (P = 0.06). In Kaplan-Meier analysis, patients with lower ADC value of upstream pancreas (<1.36 × 10(-3) mm(2)/s) were significantly associated with poor OS (P = 0.0006). In multivariate analysis, the ADC value of upstream pancreas was identified as an independent prognostic factor (P = 0.01; hazards ratio, 0.05; 95% CI, 0.004-0.59). CONCLUSIONS: The ADC value of upstream pancreas was an independent prognostic factor for OS in pancreatic cancer patients. Inflammatory environment may play an important role in pancreatic cancer progression.

Synthetic polyglycomer short-term absorbable sutures vs. polydioxanone long-term absorbable sutures for preventing incisional hernia and wound dehiscence after abdominal wall closure: a comparative randomized study of patients treated for gastric or colon cancer.

PURPOSE: To compare the results of abdominal wall closure using interrupted synthetic short-term vs. long-term tensile strength-retaining absorbable sutures. METHODS: The subjects were 55 patients undergoing elective laparotomy through a midline vertical incision for gastric or colon cancer surgery between November 2008 and August 2010, at our hospital. After providing informed consent, the patients were randomized for suturing with Polysorb(®), which provides short-term tensile strength, or with PDS(®)II, which provides long-term strength. The primary outcome analyzed was the incidence of incisional hernia or wound dehiscence. RESULT: There were 28 patients allocated to the Polysorb group and 27 to the PDS II group. Postoperative wound dehiscence was noted in two patients (3.6%). Five of 51 patients (9.8%) suffered incisional hernia within 1 year after surgery, 6 of 41 patients (14.6%) within 2 years, and 6 of 35 patients (17.1%) within 3 years. There was no significant per year difference in the incidence of incisional hernia or wound dehiscence between the groups. CONCLUSION: Outcomes were favorable in both groups and not inferior to reported outcomes of larger-scale studies. Verification of the equivalence between the two types of suture material necessitates larger-scale studies that adopt the same suture methods.

Mediastinal hematoma as an unusual intrathoracic manifestation of Boerhaave Syndrome: A case report.

INTRODUCTION: Boerhaave Syndrome (BS) is rare but life-threatening condition caused by a sudden increase in the intraluminal pressure due to vomiting. We present a case of BS manifesting as a posterior mediastinal hematoma, indicative of a potentially fatal condition. PRESENTATION OF CASE: A 51-year-old man presented with acute chest pain after vomiting. Enhanced Computed Tomography revealed mediastinal fluid with a left pleural effusion, leading to a diagnosis of BS. Emergency surgery revealed a posterior mediastinal hematoma with active bleeding due to a torn proper esophageal artery. Hemostasis and a wall repair were performed, and the patient was discharged uneventfully. DISCUSSION: This case highlights two important aspects. Firstly, a spontaneous esophageal perforation can manifest as a mediastinal hematoma due to the subpleural arterial injury, delaying bacterial spillage. While preoperative thoracentesis may not always diagnose BS accurately, bloody thoracic drainage can serve as an alternative diagnostic sign. Secondly, the mediastinal hematoma itself poses a serious risk, as it can lead to a catastrophic outcome even before bacterial contamination occurs, emphasizing the necessity of a timely surgical intervention in BS cases. CONCLUSION: BS can manifest as a mediastinal hematoma, and the absence of gastrointestinal content in the thoracic drainage does not rule out the possibility of BS. Prompt surgical intervention remains essential, as a mediastinal hematoma alone can result in a catastrophic outcome. This case highlights the significance of a comprehensive diagnostic assessment for BS.

Depicting the semicircular canals with inner-ear MRI: a comparison of the SPACE and TrueFISP sequences.

PURPOSE: To assess the ability of magnetic resonance imaging (MRI) to depict the semicircular canals of the inner ear by comparing results from the sampling perfection with application-optimized contrasts by using different flip angle evolutions (SPACE) sequence with those from the true free induction with steady precession (TrueFISP) sequence. MATERIALS AND METHODS: A 1.5-T MRI system was used to perform an in vivo study of 10 healthy volunteers and 17 patients. A three-point visual score was employed for assessing the depiction of the semicircular canals and facial and vestibulocochlear nerves and the contrast-to-noise ratio (CNR) was computed for the vestibule and pons on images with the SPACE and TrueFIPS sequences. RESULTS: There were no susceptibility artifact-related filling defects with the SPACE sequence. However, the TrueFISP sequence showed filling defects for at least one semicircular canal on both sides in seven cases for healthy subjects and in 10 cases for patients. The CNR with the SPACE sequence was significantly higher than with the TrueFISP sequence (P < 0.05). There was no statistically significant difference in depicting the facial and the vestibulocochlear nerves (P = 0.32). CONCLUSION: For the depiction of the semicircular canal, the SPACE sequence is superior to the TrueFISP sequence.

[Neoadjuvant chemotherapy for advanced colorectal cancer].

BACKGROUND: The prognosis of advanced colorectal cancer after surgical resection remains poor if curative resection cannot be achieved. Neoadjuvant chemotherapy( NAC) may increase the curative resection rate and reduce the recurrence rate following resection of marginally resectable advanced colorectal cancer by ensuring adequate surgical margin and controlling micro-metastases. Herein, we report the treatment regimen and outcomes of NAC for advanced colorectal cancer at our institute. PATIENTS AND METHODS: Between April 2005 and December 2012, 10 patients with marginally resectable advanced colorectal cancer received NAC before undergoing laparotomy. NAC consisted of 4 to 8 courses of the FOLFIRI-3 regimen combined with molecular targeted agents. Laparotomy was performed 4 to 6 weeks after the last course of NAC, and 12 courses of mFOLFOX6 were recommended as adjuvant chemotherapy after surgery. RESULTS: A partial response (PR) according to Response Evaluation Criteria in Solid Tumors ver. 3 was observed in 5 patients and progressive disease (PD) was not observed in any patient. Curative resection was achieved in 9 patients. All patients are currently alive, and the 2-year relapse-free survival rate was 62.2%. CONCLUSIONS: This is a retrospective study of a small number of subjects; however, the results suggest that NAC for marginally resectable advanced colorectal cancer increases the curative resection rate and reduces the recurrence rate.

Out-of-Plane Needle Placements Using 3D Augmented Reality Protractor on Smartphone: An Experimental Phantom Study.

PURPOSE: To evaluate the accuracy of needle placement using a three-dimensional (3D) augmented reality (AR) protractor on smartphones (AR Puncture). MATERIALS AND METHODS: An AR protractor that can be rotated in three directions against the CT plane with angle guidance lines for smartphones was developed. The protractor center can be adjusted to an entry point by manually moving the smartphone with the protractor center fixed at the center of the screen (Fix-On-Screen) or by image tracking with a printed QR code placed at an entry point (QR-Tracking). Needle placement was performed by viewing a target line in the tangent direction with the Bull's eye method. The needle placement errors placed by four operators in six out-of-plane directions in a phantom using a smartphone (iPhone XR, Apple, Cupertino, CA, USA) were compared with two registration methods. RESULTS: No significant difference in the average needle placement error was observed between the Fix-On-Screen and QR-Tracking methods (5.6 ± 1.7 mm vs. 6.1 ± 2.9 mm, p = 0.475). The average procedural time of the Fix-On-Screen method was shorter than that of the QR-Tracking method (71.0 ± 23.9 s vs. 98.4 ± 59.5 s, p = 0.042). CONCLUSION: The accuracies of out-of-plane needle placements using the 3D AR protractor with the two registration methods were equally high, with short procedure times. In clinical use, the Fix-On-Screen registration method would be more convenient because no additional markers are required.

Only surgical resection can identify the second primary lung cancer out of the metastasis after gastric cancer surgery.

OBJECTIVE: Solitary pulmonary lesions (SPLs) in patients with a history of malignancy require not only the distinction between benign and malignant, but also that between metastatic and primary lesions. We aim to establish the clinical strategy for the treatment of a solitary pulmonary lesion that is detected during the postoperative surveillance for gastric cancer. METHODS: We retrospectively examined the clinical records of the patients who underwent curative resection for gastric cancer between January 1999 and December 2009. Patients who were diagnosed with solitary pulmonary lesion during the postoperative surveillance underwent pulmonary resection, and were reviewed with regard to their histological diagnosis and prognosis. RESULTS: Out of a total of 1017 patients who underwent gastric resections during this period, 13 patients with solitary pulmonary lesion underwent pulmonary resection. These tumors were shown to be eight primary lung cancers, four metastatic tumors (three from gastric cancer) and one benign nodule. Of the eight patients with primary lung cancer, seven remained alive after pulmonary resection, including one liver metastasis case, and the other died without recurrence. In contrast, the other three patients with metastasis from gastric cancer died with distant metastasis, despite undergoing curative pulmonary resection. One of these three metastatic patients was misdiagnosed as primary lung cancer by transbronchial biopsy before surgery. CONCLUSIONS: Solitary pulmonary lesions detected during postoperative gastric cancer surveillance should undergo surgical resection to distinguish between primary and metastatic disease because of the quite different prognosis of these two entities.

Pull-through technique with pincer tactics for stent placement in severe superior vena cava syndrome.

The pull-through technique is an interventional radiological procedure used when an occluded lesion cannot be traversed from one direction. To pass the lesion, a long guidewire is traversed from the opposite side and pulled through the ipsilateral sheath using a snare wire. The present report describes a case of severe superior vena cava syndrome treated by stent placement using a pull-through technique with pincer tactics. We successfully placed a stent in the occluded right internal jugular vein to the superior vena cava using a bilateral approach by snaring a guidewire in the right subclavian vein.

[Neoadjuvant chemotherapy for recurrent colorectal cancer].

BACKGROUND: The prognosis after surgical resection of recurrent colorectal cancer is still poor, even if it is diagnosed as "resectable" before operation. Neoadjuvant chemotherapy (NAC) may reduce the recurrence rate after resection of recurrent lesions by ensuring the surgical margin and controlling micro-metastases. This report presents the treatment regimen and outcome of NAC for recurrent colorectal cancer at this institution. PATIENTS AND METHODS: Nineteen patients with recurrent colorectal cancer, excluding hepatic and pulmonary metastases, received NAC before laparotomy between April 2005 and November 2011. The FOLFIRI3 regimen combined with molecular targeting agents was used for NAC, and 4 to 8 courses were administered. Laparotomy was performed during the 4-to 6-week period after the last NAC administration, and 12 courses of mFOLFOX6 were recommended as adjuvant chemotherapy after the operation. RESULTS: Complete remission was observed in 1 patient and partial remission in 7 patients according to Response Evaluation Criteria in Solid Tumors ver. 3, and no progressive disease was observed. Curative resection was achieved in 13 patients. The 3-year overall survival rate was 83.6%, and the 3-year relapse-free survival rate was 50.3%. CONCLUSION: This retrospective study using a small number of subjects suggested that NAC for recurrent colorectal cancer may increase the curative resection rate while reducing the recurrence rate.

Noncontact measurement of puncture needle angle using augmented reality technology in computed tomography-guided biopsy: stereotactic coordinate design and accuracy evaluation.

PURPOSE: This study aims to introduce a new handheld device application for noncontact and real-time measurements of the angle of a biopsy needle using augmented reality (AR) image tracking technology. Furthermore, this study discusses the methods used to optimize the related coordinate design for computed tomography (CT)-guided biopsy procedures. METHODS: An in-house noncontact angle measurement application was developed using AR platform software. This application tracks the position and direction of a printed texture located on the handle of a biopsy needle. The needle direction was factorized into two directions: tilting or rolling. Tilting was defined following the tilting of the CT gantry so that rolling would match the angle measured in CT images. In this study, CT-guided tumor biopsies were performed using a conventional guiding method with a protractor. The true value of needle rolling was measured by CT imaging and was then compared to the rolling measurement provided by the application developed in the current study using a mobile phone. RESULTS: This study enrolled 18 cases of tumor biopsy (five renal tumors, five lung tumors, four retroperitoneal tumors, one soft tissue tumor, one thyroid tumor, one mesentery tumor, and one bone tumor). The measurement accuracy was - 0.2°, which was the average difference between AR and CT, and the measurement precision was 2.0°, which was the standard deviation of the difference between AR and CT measurements. The coefficient of determination (R2) was 0.996. CONCLUSION: The noncontact needle measurement software using AR technology is sufficiently reliable for use in clinical settings. A real-time display of the needle angle that also shows the direction of the CT gantry is expected to enable a simple biopsy needle navigation.

Mixed Reality Needle Guidance Application on Smartglasses Without Pre-procedural CT Image Import with Manually Matching Coordinate Systems.

PURPOSE: To develop and assess the accuracy of a mixed reality (MR) needle guidance application on smartglasses. MATERIALS AND METHODS: An MR needle guidance application on HoloLens2, without pre-procedural CT image reconstruction or import by manually matching the spatial and MR coordinate systems, was developed. First, the accuracy of the target locations in the image overlay at 63 points arranged on a 45 × 35 × 21 cm box and needle angles from 0° to 80°, placed using the MR application, was verified. The needle placement errors from 12 different entry points in a phantom by seven operators (four physicians and three non-physicians) were compared using a linear mixed model between the MR guidance and conventional methods using protractors. RESULTS: The average errors of the target locations and needle angles placed using the MR application were 5.9 ± 2.6 mm and 2.3 ± 1.7°, respectively. The average needle insertion error using the MR guidance was slightly smaller compared to that using the conventional method (8.4 ± 4.0 mm vs. 9.6 ± 5.1 mm, p = 0.091), particularly in the out-of-plane approach (9.6 ± 3.5 mm vs. 12.3 ± 4.6 mm, p = 0.003). The procedural time was longer with MR guidance than with the conventional method (412 ± 134 s vs. 219 ± 66 s, p < 0.001). CONCLUSION: MR needle guidance without pre-procedural CT image import is feasible when matching coordinate systems, and the accuracy of needle insertion is slightly better than that of the conventional method.

New standards for phantom image quality and SUV harmonization range for multicenter oncology PET studies.

Not only visual interpretation for lesion detection, staging, and characterization, but also quantitative treatment response assessment are key roles for 18F-FDG PET in oncology. In multicenter oncology PET studies, image quality standardization and SUV harmonization are essential to obtain reliable study outcomes. Standards for image quality and SUV harmonization range should be regularly updated according to progress in scanner performance. Accordingly, the first aim of this study was to propose new image quality reference levels to ensure small lesion detectability. The second aim was to propose a new SUV harmonization range and an image noise criterion to minimize the inter-scanner and intra-scanner SUV variabilities. We collected a total of 37 patterns of images from 23 recent PET/CT scanner models using the NEMA NU2 image quality phantom. PET images with various acquisition durations of 30-300 s and 1800 s were analyzed visually and quantitatively to derive visual detectability scores of the 10-mm-diameter hot sphere, noise-equivalent count (NECphantom), 10-mm sphere contrast (QH,10 mm), background variability (N10 mm), contrast-to-noise ratio (QH,10 mm/N10 mm), image noise level (CVBG), and SUVmax and SUVpeak for hot spheres (10-37 mm diameters). We calculated a reference level for each image quality metric, so that the 10-mm sphere can be visually detected. The SUV harmonization range and the image noise criterion were proposed with consideration of overshoot due to point-spread function (PSF) reconstruction. We proposed image quality reference levels as follows: QH,10 mm/N10 mm ≥ 2.5 and CVBG ≤ 14.1%. The 10th-90th percentiles in the SUV distributions were defined as the new SUV harmonization range. CVBG ≤ 10% was proposed as the image noise criterion, because the intra-scanner SUV variability significantly depended on CVBG. We proposed new image quality reference levels to ensure small lesion detectability. A new SUV harmonization range (in which PSF reconstruction is applicable) and the image noise criterion were also proposed for minimizing the SUV variabilities. Our proposed new standards will facilitate image quality standardization and SUV harmonization of multicenter oncology PET studies. The reliability of multicenter oncology PET studies will be improved by satisfying the new standards.

Perfusion fraction of diffusion-weighted MRI for predicting the presence of blood supply in ovarian masses.

PURPOSE: To evaluate whether perfusion fraction (PF) calculated with diffusion-weighted magnetic resonance imaging (MRI) predicts the presence of blood supply in ovarian masses. MATERIALS AND METHODS: PFs of 92 ovarian lesions in 53 patients administered gadolinium were retrospectively calculated with diffusion-weighted images at b-values of 0, 500, and 1000 sec/mm(2). PFs were compared between ovarian lesions, except for fat, with (n = 21) or without contrast enhancement (n = 57), using Student's t-test and receiver operating characteristics (ROC) curve analysis. Lesion enhancement rates of contrast-enhanced images at 30 and 180 seconds after gadolinium injection (ER(30sec) and ER(180sec)) and PFs were compared using Pearson's correlation coefficient. RESULTS: PFs of the lesions with contrast enhancement were significantly higher than those without contrast enhancement (0.22 ± 0.09 and 0.02 ± 0.08, respectively, P < 0.0001). The ROC curve identified the best cutoff point for PF at 0.135 (95.2% sensitivity and 94.7% specificity) as a predictor of the contrast enhancement effect. The area under the ROC curve was 0.984. PF correlated moderately with ER(30sec) (0.62, y = 0.13x + 0.04, P < 0.0001) and ER(180sec) (0.74, y = 0.13x + 0.03, P < 0.0001). CONCLUSION: PF calculated with diffusion-weighted images can potentially predict blood supply in ovarian masses.

Unenhanced ECG-gated fast spin-echo MR digital subtraction angiography (MRDSA) using short echo-spacing three-dimensional sequence of femoral arteries: initial experience.

PURPOSE: To compare the image qualities of unenhanced electrocardiographically (ECG)-gated fast spin-echo magnetic resonance digital subtraction angiography (MRDSA) using a short echo-spacing three-dimensional (3D) sequence, known as sampling perfection with application-optimized contrasts using different flip angle evolutions (SPACE), and the conventional half-Fourier single-shot turbo spin-echo (HASTE) sequence. MATERIALS AND METHODS: Unenhanced ECG-gated MRDSA using SPACE and HASTE of the femoral arteries were prospectively acquired in 13 healthy volunteers at 1.5 Tesla (T) MRI. Sequential frontal maximum-intensity-projection images produced by subtracting each of 10 systolic images from a diastolic image were evaluated quantitatively using paired t-test and qualitatively by two blinded radiologists using the Mann-Whitney U-test. RESULTS: Quantitatively, relative contrast against the background, contour sharpness index, and slope of the sequential signal changes of the superficial femoral artery of MRDSA using SPACE were significantly better than those of HASTE (P = 0.005, P = 0.001, and P < 0.0001, respectively). Qualitatively, the overall subjective image quality and sequential appearance changes of MRDSA using SPACE were significantly better than those of HASTE (P < 0.0001 and P < 0.0001, respectively). CONCLUSION: Unenhanced ECG-gated fast spin-echo MRDSA using SPACE produces increments in signal intensity, which reflect arterial pulse wave transmission, more clearly than the conventional HASTE sequence.