The basilic vein and the cephalic vein perform equally in upper arm arteriovenous fistulae.

OBJECTIVE: To compare the brachiocephalic (BC) and basilic vein transposition (BVT) arteriovenous fistula (AVF) with regard to maturation, patency, blood flow and complication rates. DESIGN: A retrospective chart review. MATERIALS AND METHOD: Between January 2000 and December 2010, consecutive patients undergoing BC or BVT AVF were included. Patient characteristics were collected retrospectively from digital patient files and a prospective database of haemodialysis patients. RESULTS: A total of 173 autologous upper arm AVFs (87 BC and 86 BVT) were created in 151 patients. Mean (±SEM) follow-up was 19 ± 1.4 months (range 0-100). There were no differences between the groups in respect to brachial artery and cubital fossa vein diameters, time to first use, flow and the number of secondary interventions. Operative time was significantly longer (P < 0.001) and the mid upper arm vein diameter before bifurcation greater (P = 0.038) in BVT patients. The 1- and 2-year primary patency rates for the whole cohort was 40.8% and 30.2% with secondary patency rates of 78.0% and 72.4%. There was no difference between the groups for these outcomes (P = 0.951, P = 0.516, respectively). CONCLUSION: With the exception of the efferent vein diameter in the mid upper arm and operative time, there was no difference between a BC and BVT AVF.

Perforating veins: an anatomical approach to arteriovenous fistula performance in the forearm.

OBJECTIVES: Arteriovenous fistulae (AVFs) play a key role for people who rely on chronic haemodialysis. Stenosis in the venous outflow of the AVF will cause an alternative route of the subcutaneous blood flow via the deeper venous pathways by means of side branches and the perforating veins (PVs). The purpose for the present study was to define the number and anatomical localisation of the perforating veins in the forearm. METHODS: Twenty forearms were dissected to study the venous anatomy. The localisation, size and connections of the perforators were recorded and stored digitally. RESULTS: In total, 189 PVs were defined (mean, 9.5 per arm; range, 6-19), with 60 (32%) PVs connected to the cephalic vein, 97 (51%) connections to the basilic vein and 32 (17%) PVs to the median vein of the forearm. Most PVs originate from the basilic vein and connect with the ulnar venae comitans. The cephalic vein connects equally to the radial venae comitans, interossea veins and the muscles. CONCLUSION: The cephalic vein has the fewest PVs and almost a third of them connect to the muscles. This is probably important for the maturation of the AVF, the superficial flow volume and the accessibility for puncture.

Multi-slice computed tomographic angiography for stenosis detection in forearm hemodialysis arteriovenous fistulas.

PURPOSE: A method of diagnosing the extent and severity of arteriovenous fistula (AVF) stenoses is multislice computed tomographic angiography (MS-CTA). The aim of this prospective study was to assess the accuracy of MS-CTA for the detection and grading of stenoses in AVF in comparison to digital subtraction angiography (DSA), which was used as the gold standard of reference. METHODS: Fifteen hemodialysis (HD) patients with dysfunctioning forearm AVF were included. These AVFs were evaluated by both DSA and MS-CTA and were read in a prospective, blinded manner by two radiologists experienced in vascular imaging. RESULTS: ROC analysis revealed areas under the curve of 0.90+/-0.07 for observer I and 0.87+/-0.08 for observer II at a stenosis cut-off level of >or=50% diameter reduction. The combined results for MS-CTA showed sensitivity, specificity and positive and negative predictive values of 82%, 98%, 82% and 98% for stenoses>or=50% and 71%, 99%, 77% and 98% for stenoses>or=75%. Inter-observer agreement for the detection of stenoses>or=50% diameter reduction was 0.70 and 1.0, for MS-CTA and DSA, respectively. CONCLUSION: MS-CTA can provide good visualization of forearm HD access AVF and has moderate sensitivity, but high specificity for the detection of flow-limiting stenoses.

Classification and localization of acetabular labral tears.

OBJECTIVE: The purpose of this study was to compare the findings on hip MR arthrography (MRA) with the published MRA and arthroscopic classifications of hip labral tears and to evaluate a clock-face method for localizing hip labral tears. DESIGN/PATIENTS: We retrospectively reviewed 65 hip MRA studies with correlative hip arthroscopies. Each labrum was evaluated on MRA using the classification system of Czerny and an MRA modification of the Lage arthroscopic classification. In addition, each tear was localized on MRA by using a clock-face description where 6 o'clock was the transverse ligament and 3 o'clock was anterior. These MRA findings were then correlated with the arthroscopic findings using the clock-face method of localization and the Lage arthroscopic classification of labral tears. RESULTS: At MRA, there were 42 Czerny grade 2 and 23 grade 3 labral tears and 22 MRA Lage type 1, 11 type 2, 22 type 3 and 10 type 4 tears. At arthroscopy, there were 10 Lage type 1 flap tears, 20 Lage type 2 fibrillated tears, 18 Lage type 3 longitudinal peripheral tears and 17 Lage type 4 unstable tears. The Czerny MRA classification and the modified MRA Lage classification had borderline correlation with the arthroscopic Lage classification. Localization of the tears using a clock-face description was within 1 o'clock of the arthroscopic localization of the tears in 85% of the patients. CONCLUSIONS: The Lage classification, which is the only published arthroscopic classification system for hip labral tears, does not correlate well with the Czerny MRA or an MRA modification of the Lage classification. Using a clock-face description to localize tears provides a way to accurately localize a labral tear and define its extent.

Hand assisted laparoscopic surgery of aortoiliac occlusive disease: initial results.

OBJECTIVES: Open aortobifemoral bypass grafting has been the procedure of choice for many years in patients with symptomatic aortoiliac occlusive disease (AIOD). Hand assisted laparoscopic surgery (HALS) for AIOD could have advantages like faster recovery, faster oral intake and shorter hospital stay compared to the conventional technique. We documented the results of patients who underwent HALS for AIOD in our hospitals. MATERIALS AND METHODS: from January 1999 to December 2002, 33 consecutive patients underwent HALS for AIOD. Peri- and postoperative results were prospectively registered. Three different laparoscopic approaches were applied: transperitoneal, retroperitoneal and apron approach. RESULTS: There were 23 males and 10 females, with a mean age of 59 years (range 39-85). The surgical technique applied was: transperitoneal: 22 patients, retroperitoneal: 7 patients, apron: 4 patients. Per-operative results (median) of the transperitoneal, retroperitoneal and apron approach are: operating time 240, 420 and 263 minutes, cross clamp time 32.5, 40 and 33.5 minutes, blood loss 1150, 2100 and 950 ml, respectively. Postoperatively oral intake was fully resumed in 3, 4.5 and 2 days after performing the transperitoneal, retroperitoneal and apron technique. During the ICU stay patients received artificial respiration for 0, 1 and 0 days, admission to the ICU was 0.5, 1 and 0.75 days for the transperitoneal, retroperitoneal and apron approach. Finally, hospital stay was 8, 12.5 and 7 days after the transperitoneal, retroperitoneal and apron approach. Four patients (12%) had a minor complication, 4 patients (12%) had a major complication; pneumonia with ARDS, sepsis, bypass occlusion and chylo-abdomen. No patients died. CONCLUSIONS: HALS for AIOD is a technically demanding operation with a long learning curve. All three approaches are feasible. In this series of patients, we feel the transperitoneal and apron approach have the most advantages because of the larger working space. Finally, randomized trials will determine if laparoscopic assisted or total laparoscopic aortoiliac surgery has the potential to reduce morbidity for the patient compared to the conventional technique.

Autogenous radial-cephalic or prosthetic brachial-antecubital forearm loop AVF in patients with compromised vessels? A randomized, multicenter study of the patency of primary hemodialysis access.

OBJECTIVE: The construction of an autogenous radial-cephalic direct wrist arteriovenous fistula (RCAVF) is the primary and best option for vascular access for hemodialysis. However, 10%-24% of RCAVFs thrombose directly after operation or do not function adequately due to failure of maturation. In case of poor arterial and/or poor venous vessels for anastomosis, the outcome of RCAVFs may be worse and an alternative vascular access is probably indicated. A prosthetic graft implant may be a second best option. Therefore, a randomized multicenter study comparing RCAVF with prosthetic (polytetrafluoroethylene [PTFE]) graft implantation in patients with poor vessels was performed. METHODS: A total of 383 consecutive new patients needing primary vascular access were screened for enrollment in a prospective randomized study. According to defined vessel criteria from the preoperative duplex scanning, 140 patients were allocated to primary placement of an RCAVF and 61 patients to primary prosthetic graft implantation. The remaining 182 patients were randomized to receive either an RCAVF (n = 92) or prosthetic graft implant (n = 90). Patency rate was defined as the percentage of AVFs that functioned well after implantation. RESULTS: Primary and assisted primary 1-year patencies were 33% +/- 5.3% vs 44% +/- 6.2% (P = .03) and 48% +/- 5.5% vs 63% +/- 5.9% (P = .035) for the RCAVF and prosthetic AVF, respectively. Secondary patencies were 52% +/- 5.5% vs 79% +/- 5.1% (P = .0001) for the RCAVF and prosthetic AVF, respectively. Patients with RCAVFs developed a total of 102 (1.19/patient-year [py]) vs 122 (1.45/py; P = .739) complications in the prosthetic AVFs. A total of 43 (0.50/py) interventions in the RCAVF group and 79 (0.94/py) in the prosthetic graft group were needed for access salvage (P = .077). CONCLUSIONS: Although there were more interventions needed for access salvage in the patients with prosthetic graft implants, we may conclude that patients with poor forearm vessels do benefit from implantation of a prosthetic graft for vascular access.

Abnormal superior popliteomeniscal fascicle and posterior pericapsular edema: indirect MR imaging signs of a lateral meniscal tear.

OBJECTIVE: Because MR diagnosis of lateral meniscal tears can be difficult, indirect signs may be useful when a tear is suspected. We studied whether an abnormality of the superior popliteomeniscal fascicle or pericapsular edema was associated with lateral meniscal tears and thus may be an indirect MR imaging sign of a lateral meniscal tear. MATERIALS AND METHODS: We identified 59 consecutive patients who underwent both knee MR imaging examinations and knee arthroscopy. Thirty patients had lateral meniscal tears, and 29 had intact lateral menisci. We reviewed paired sagittal proton density- and T2-weighted MR images from these 59 patients for abnormal superior popliteomeniscal fascicles and edema surrounding the posterolateral capsule. RESULTS: The superior popliteomeniscal fascicles were abnormal in nine of the 30 patients with torn lateral menisci but were normal in all 29 patients with intact menisci (p = 0.001). Abnormal fascicles were apparent only when the lateral meniscal tear involved the posterior horn. Posterior pericapsular edema was seen in 10 patients with a torn posterior horn and in one patient with an anterior horn tear of the lateral meniscus, but in only two patients with intact menisci (p = 0.006). CONCLUSION: The presence of superior popliteomeniscal fascicle abnormalities and of posterior pericapsular edema is significantly associated with a tear of the lateral meniscus, most commonly in the posterior horn. Noting the presence of these findings may help improve the accuracy of MR diagnosis of lateral meniscal tears.

Noninvasive evaluation before and after percutaneous therapy of iliac artery stenoses: the value of the Bernoulli-predicted pressure gradient.

PURPOSE: The purpose of this study was to assess the value of the Bernoulli-predicted pressure gradient in the noninvasive evaluation of patients undergoing iliac percutaneous transluminal angioplasty (PTA) or stent placement with the use of intra-arterial pressure measurements as the standard of reference. METHODS: Stent placement or PTA was performed in 261 patients with intermittent claudication caused by iliac artery stenoses (333 procedures). Intra-arterial translesional pressure gradients were recorded before and after each procedure. Hemodynamic success was defined as a postprocedural mean pressure gradient less than or equal to 10 mm Hg at rest and during vasodilatation. Before and after intervention, the following noninvasive parameters were determined: the Bernoulli-predicted pressure gradient, the peak systolic velocity ratio, and the ankle-brachial pressure index. RESULTS: Before treatment, both the intra-arterial-measured pressure gradients and the Bernoulli-predicted gradients indicated hemodynamic significance of the iliac artery stenoses. After treatment, both methods indicated significant improvement of the translesional pressure gradient (P <. 0001). However, the correlation between the intra-arterially measured pressure gradient and the Bernoulli-predicted gradient of iliac artery stenoses was low (Pearson's r = 0.27). None of the three investigated noninvasive methods could differentiate an optimal PTA or stent result from a suboptimal result, as assessed by intra-arterial pressure measurements. CONCLUSIONS: The disappointing correlation among the duplex velocity data, whether expressed as pressure gradient or as a peak systolic velocity ratio, and the actually measured pressure gradient might be caused by errors in pressure or velocity measurements or the different circumstances in which the pressure or velocity measurements were performed. Residual pressure gradients after iliac PTA or stent placement assessed with intra-arterial pressure measurements could not be assessed with the investigated noninvasive methods.

Superior labrum anterior-posterior (SLAP) tears: evaluation of three MR signs on T2-weighted images.

PURPOSE: To compare the sensitivity and specificity of three magnetic resonance (MR) imaging signs for the diagnosis of superior labrum anterior-posterior (SLAP) tears. MATERIALS AND METHODS: The study involved 23 consecutive patients with a type 2, 3, or 4 SLAP tear at arthroscopy and 31 age-matched control patients with an arthroscopically normal or type 1 SLAP lesion. The superior labrum was evaluated on MR images for high signal intensity extending to the articular surface in the posterior third of the labrum, an irregular or laterally curved area of high signal intensity, or two high-signal-intensity lines. RESULTS: The sensitivity, specificity, and accuracy of posterior high signal intensity for a type 2, 3, or 4 SLAP tear were 48%, 94%, and 74%, respectively, for observer 1 and 61%, 81%, and 72%, respectively, for observer 2. For laterally curved area of high signal intensity, these values were 65%, 84%, and 76%, respectively, and 56%, 84%, and 72%, respectively. For two high-signal-intensity lines, these values were 17%, 94%, and 61%, respectively, and 13%, 94%, and 59%, respectively. For the presence of either posterior or laterally curved high signal intensity, the sensitivity was 65% for both observers, whereas the specificity was 84% for observer 1 and 74% for observer 2. The kappa values for interobserver agreement were 0.60 for posterior high signal intensity and 0.58 for laterally curved high signal intensity. CONCLUSION: Laterally curved and posterior high signal intensities are specific signs for distinguishing a SLAP tear from a normal-variant superior sublabral recess.

"Dem bones": osteochondral injuries of the knee.

MR imaging plays a valuable role in the diagnosis and staging of osteochondral injuries of the femorotibial joint. Bone contusions may be the source of a patient's pain, and MR imaging characteristics of certain types may help to predict which contusions might progress to more serious osteochondral lesions. MR imaging also is vital in the diagnosis of occult osteochondral fractures and in accurately classifying displaced intra-articular fractures. Although osteochondral dissecans usually is diagnosed radiographically, MR imaging is the best noninvasive test for determining if an osteochondral fragment is unstable. Unstable lesions are a treatable cause of knee pain.

MR imaging of the distribution and location of acute hamstring injuries in athletes.

OBJECTIVE: Although hamstring injuries are common in athletes, the distribution and location of such injuries have not been well defined. We used MR imaging to determine the frequency of injury by muscle, involvement of one or more muscles, and location of injuries within the musculotendinous unit. SUBJECTS AND METHODS: We performed MR imaging on 15 consecutive college athletes with clinically diagnosed acute hamstring injuries. A hamstring injury was diagnosed and located on MR imaging by identifying high signal intensity within the muscle on T2-weighted images. RESULTS: We found that 10 athletes had injuries of a single muscle with six injuries of the biceps femoris, three of the semitendinosus, and one of the semimembranosus. In an additional five athletes, we found primary injuries of the biceps femoris and secondary injuries of the semitendinosus. The injuries occurred in diverse locations within the muscles including five injuries at the proximal musculotendinous junction, two at the distal musculotendinous junction, four within the proximal half of the muscle belly, and four in the distal half. All eight intramuscular injuries were located at the musculotendinous junction within the muscle. CONCLUSION: The biceps femoris is the most commonly injured hamstring muscle and the semitendinosus is the second most commonly injured. Although hamstring injuries often involve one muscle injured proximally, multiple muscles were involved in 33% of athletes (5/15) and the injuries were distal in 40% of athletes (6/15). All intramuscular injuries occurred at the musculotendinous junction, either at the ends of the muscle or within the muscle belly.

MR visualization of the popliteomeniscal fascicles.

OBJECTIVE: Although the popliteomeniscal fascicles are important stabilizers of the lateral meniscus, there have been few studies of their MR appearance. We wished to determine: (1) whether the fascicles are normally seen on MR imaging, and (2) whether certain imaging factors influenced their visualization. DESIGN AND PATIENTS: We reviewed the sagittal MR images of 66 consecutive patients who had no evidence of injury to the lateral compartment. We determined the frequencies of MR visualization of the superior and inferior popliteomeniscal fascicles, and whether visualization was affected by the weighting of spin echo sequences, the presence of a joint effusion, slice placement relative to the fascicles, and windowing of the images. RESULTS AND CONCLUSIONS: Both popliteomeniscal fascicles were seen in 64 of the 66 patients. The fascicles were better seen on T2-weighted images than on proton-density weighted images (P<0.01). On the T2-weighted images, fascicle visualization was not significantly affected by the presence or absence of an effusion, slice placement or image windowing (P=0.2 to 1.0). On proton-density weighted images, fascicle visualization was significantly improved when high-contrast windowing was used (P=0.04). In conclusion, we found that the popliteomeniscal fascicles are normally seen on MR imaging of the knee when there are no lateral compartment injuries. The fascicles are significantly better visualized on T2-weighted than on proton-density weighted images. Visualization is not significantly affected by the presence of an effusion or slice placement.

Are oblique views needed for trauma radiography of the distal extremities?

OBJECTIVE: To our knowledge, few studies exist on the importance of the oblique view when radiography of the distal extremities is performed after acute trauma. Our prospective study aimed to determine whether the oblique view uniquely revealed abnormalities or clarified findings when it was obtained along with routine frontal and lateral radiographs. SUBJECTS AND METHODS: We prospectively interpreted 1461 consecutive radiographic examinations of the distal extremities in patients presenting with acute trauma to four family medicine clinics. The anatomic sites radiographed included the ankle, foot, toe, wrist, hand, finger, and thumb. Each study was interpreted and given a diagnostic certainty score using the lateral and posteroanterior or anteroposterior views only and then scored again with the oblique view added. RESULTS: The examinations included 421 with abnormal findings, 34 with equivocal findings, and 1006 with normal findings. The addition of the oblique view changed the interpretation in 70 (4.8%) of the 1461 examinations. Of these changed interpretations, 39 were changed from equivocal to either positive or negative, three from positive to negative, and 28 from negative to positive. Addition of the oblique view increased diagnostic confidence: The percentage of examinations scored as having probably normal, equivocal, and probably abnormal findings decreased from 13.9% with two views to 8.4% with three views (p < .0001). The oblique view was equally valuable in the ankle, foot, toe, wrist, hand, finger, and thumb. CONCLUSION: In the distal extremities, the oblique view uniquely reveals abnormalities and increases the confidence of the final radiographic diagnosis when the oblique view is interpreted along with frontal and lateral radiographs.

The hypothenar hammer syndrome: update and literature review.

The hypothenar hammer syndrome is a rather rare vascular injury. It is seen in posttraumatic digital ischaemia caused by irregularity or occlusion of the distal ulnar artery at the level of the hamate bone. It characteristically occurs in the dominant hand of middle-aged men whose occupational or recreational activities require the use of the hand as a hammer. Three typical cases are presented along with literature review. The different aspects of this syndrome are described such as the cause and pathogenesis, the most important clinical characteristics and differential diagnosis, the role of angiography and Doppler mapping in establishing the diagnosis and the various therapeutic options, ranging from conservative treatment to resection of the thrombosed artery segment with vein graft interposition.

Untreated osteochondritis dissecans of the femoral condyles: prediction of patient outcome using radiographic and MR findings.

OBJECTIVE: We investigated the usefulness of plain film and MR findings in predicting the outcome of conservatively treated patients with femoral osteochondritis dissecans. DESIGN: Without knowledge of the clinical outcome, we retrospectively reviewed the initial plain films and MR examinations. Each MR examination was evaluated for the four MR findings of instability. PATIENTS: Fourteen patients were studied in whom osteochondritis dissecans of a femoral condyle had been treated conservatively for periods ranging from 1.2 to 8.5 years. RESULTS AND CONCLUSION: Three of five patients with an open femoral growth plate and one of nine patients with a closed growth plate had a good clinical outcome. Both patients with lesions smaller than 160 mm2 in area had a good outcome and ten of 12 patients with larger lesions had a poor outcome. Both patients with stable lesions by MR imaging had a good outcome while ten of 12 patients with a lesion unstable by MR imaging had poor outcomes. All six patients with a cartilage fracture or articular defect had poor outcomes. The results of this study should be considered preliminary since only 14 patients were followed. However, it appears that a good clinical outcome is likely when the femoral growth plate is open, when the osteochondritis dissecans is small, and when the lesion is stable by MR imaging. When a cartilage fracture or articular defect is found on MR imaging, the patient is likely to have a poor outcome.