Closed ruptures of the flexor digitorum tendons: MRI evaluation.

OBJECTIVE: To assess the MRI findings in cases of closed rupture of the flexor digitorum tendons (FDT). PATIENTS AND DESIGN: Ten patients with a clinical suspicion of rupture of FDT underwent MRI before surgery. None of the patients presented a skin injury. Fingers were imaged using axial T1-weighted SE sequences, three-dimensional GE images, and curved reconstructions. RESULTS: Twelve FDT had surgical confirmation of rupture. Flexor digitorum profundus (FDP) and flexor pollicis longus (FPL) tendons were more frequently ruptured (n=8) than flexor digitorum superficialis (FDS) tendons (n=4). MR images accurately depicted the level of the rupture. The gap between the tendon ends (mean 45 mm, range 21-70 mm) was assessed best with curved reconstructions and was well correlated with the surgical findings. The proximal end mainly retracted into the palm or the carpal tunnel (n=8), and less frequently into the digital canal (n=4). In two cases, the proximal end curled up in the palm, clinically simulating a rupture of a lumbrical muscle in one case. MRI also showed the appearance of the adjacent tendons. CONCLUSION: MRI accurately depicted the level of rupture and the gap between the tendon ends, which assisted the surgical choice between suture, graft or tendon transfer.

Contribution of magnetic resonance imaging for the diagnosis of median nerve lesion after endoscopic carpal tunnel release.

Deterioration of pre-existing signs or appearance of a nerve deficit raise difficult problems during the complicated course following endoscopic carpal tunnel release. One possible explanation is transient aggravation of nerve compression by passage of the endoscopy material, but these signs may also be due to incomplete section of the flexor retinaculum or an iatrogenic nerve lesion. Each case raises the problem of surgical revision. The authors report three cases of open revision in which MRI allowed a very precise preoperative diagnosis of the lesions and all of the MR findings were confirmed during surgical revision. In the first case, MRI showed section of the most radial branches of the median nerve (collateral nerves of the thumb, index finger and radial collateral nerve of the middle finger). The proximal origin of the nerve of the 3rd web space, above the retinaculum, an anatomical variant, was also identified. Section of 2/3 of the nerve of the 3rd web space, proximal to the superficial palmar arch, was observed in the second case. Simple thickening of the nerve of the 3rd web space, without disruption after opening of the perineurium, was observed in the third case. MRI therefore appears to be an examination allowing early and precise definition of indications for surgical revision in this new iatrogenic disease.

Complications of flexor tendon repair in the hand: MR imaging assessment.

PURPOSE: To determine if magnetic resonance (MR) imaging enables differentiation of adhesions from tendon rupture after repair of digital flexor tendon injuries. MATERIALS AND METHODS: The reference group comprised eight tendon sutures with a good clinical outcome. Axial and sagittal spin-echo sequences and three-dimensional gradient-echo sequences with curved reconstructions were analyzed in 63 injured fingers. Reoperation was performed in 41 fingers. RESULTS: MR imaging depicted isolated peritendinous adhesions (n = 31), most often with a continuous, uniform tendon (sensitivity 91%, specificity 100%). There were two types of rupture: frank rupture (n = 140; sensitivity 100%, specificity 100%) or elongated callus (n = 18; sensitivity 100%, specificity 94%). Tendon gap was significantly longer in frank rupture (P = .0011). Thin fibrous continuity existed with elongated callus. Tenolysis was sufficient when the callus was short and mature with predominant new collagen fibers. Axial spin-echo sections were essential, as they showed the maturation of the callus. CONCLUSION: MR imaging may enable distinction among several complications that occur after repair of an injured digital flexor tendon.

[Imaging of external instabilities of the patella. State of the art]. / Imagerie des instabilités externes de la rotule. Mise au point.

External femoropatellar instability is a dynamic abnormality from various origins: osseous, cartilaginous or musculotendinous; X-rays films cannot give a precise enough description of this phenomenon. Attention is drawn by anterior pain or a sensation of instability. Clinical analysis distinguishes between permanent, traumatic or transient dislocations which are now more frequently discovered as part of a femoro-patellar syndrome with or without cartilage involvement. Conventional imaging, CT-scan and MR imaging are based on faultless techniques. Lateral views precisely report femoropatellar architectural abnormalities and patellar instability. Skyline views are able to quantify the various parts of the dysplasia. Dynamic tests increase the sensitivity of the plain films. But the main shortcoming of these techniques is the lack of visualization of the initial patellar engagement in the trochlea. The femoropatellar component of the knee arthrography visualizes rather large cartilaginous lesions. CT-scan, better than skyline views, allows examining the patellar bone without interference with the trochlea (extended knee), during the engagement (15 degrees flexed knee) and after the engagement (30 degrees flexed knee). However, the examination technique varies from one author to another according to his own pathophysiologic understanding. With the bicondylar plane reference, the reliability of the CT-scan measurements are better than skyline views. Like the dynamic tests during the beginning of the patellar engagement at 15 degrees, flexion is more sensitive than those at 30 degrees. Finally, CT-scan arthrography demonstrates thinner cartilaginous lesions than conventional arthrography. Presently the main contribution of MR imaging consists of detecting transient patellar dislocation that a single clinical examination cannot differentiate from other internal knee disorders. MR imaging is more precise in analyzing the cartilaginous structure. Kinematic MR imaging, still in an experimental stage, offers a new approach to the dynamic study of the patellar tracking.

Median nerve suture in the distal part of the forearm. MRI evaluation.

The aim of the study was to assess MR images of median nerve suture in the distal part of the forearm on fresh cadavers and injured patients. The median nerve was dissected in the distal one-third of the forearm in four fresh cadaveric specimens, divided and repaired in three of them in two cases with 3/0 nylon (one with well-apposed edges and the other with a lateral gap) and, in the third specimen, with 9/0 nylon with well apposed edges. The course of the median nerve was then studied on MR imaging in different planes and the quality of the nerve repair was evaluated. A good correlation was found between the MR images and the type of nerve suture. These findings were applied in management of two clinical cases in whom reexploration and revision of the median nerve repair was carried out.

Subungual glomus tumors: evaluation with MR imaging.

PURPOSE: To determine the magnetic resonance (MR) imaging features of subungual glomus tumors. MATERIALS AND METHODS: Thirty-one patients with a clinical suspicion of glomus tumor and 10 control subjects underwent MR imaging at 1.5 T. MR images of normal glomus bodies of a cadaver finger were correlated with histologic slices. With a local surface gradient coil, the pixel size reached 117 microns in one direction. Relaxation times were measured. Gadoterate meglumine was injected in 19 patients. RESULTS: Normal glomus bodies were visualized in the reticular dermis of the nail bed. Twenty-seven of 28 pathologically confirmed glomus tumors were detected with MR imaging. A peripheral capsule was present in most tumors. The nail matrix was compressed in 13 cases. The authors were able to differentiate three subtypes of glomus tumors (vascular, solid, and myxoid) on the basis of relaxation times and enhancement characteristics. Four patients had mucoid cysts or angioma in the nail bed. CONCLUSION: MR imaging can help accurately define the location and limits of glomus tumors before excision.

Acute trauma of the extensor hood of the metacarpophalangeal joint: MR imaging evaluation.

PURPOSE: To assess detectability of the components of the extensor hood, especially the sagittal bands, with magnetic resonance (MR) imaging in normal and injured metacarpophalangeal (MP) joints. MATERIALS AND METHODS: T2*-weighted, T1-weighted, and contrast material-enhanced T1-weighted images were obtained of 54 normal MP joints (108 sagittal bands). The ability to detect the sagittal bands with each sequence was rated for three observers. These same sequences were used for MR imaging of nine patients with acute MP injury. Seven patients underwent surgery. RESULTS: The sensitivity of MR imaging for the detection of normal sagittal bands was 0.89-0.92 for T2*-weighted images, 0.80-0.88 for T1-weighted images, and 0.81-0.91 for contrast-enhanced T1-weighted images. MR imaging findings in patients with extensor hood injury included irregularity, poor definition, and increased signal intensity or uptake of contrast material by structures in and around the extensor hood. All MR imaging findings correlated well with those of surgery. CONCLUSION: MR imaging is accurate for determination of the presence and severity of injury to the extensor hood.

[Villonodular synovitis of the knee. Contributions of MRI]. / Synovite villo-nodulaire du genou. Apports de l'IRM.

This retrospective study included eight patients with villonodular synovitis of the knee (7 nodular forms and one villous form) who underwent magnetic resonance imaging and at least one arthroscopy. Joint enlargement and mild pain were the main manifestations. Other imaging studies provided little information. Magnetic resonance imaging showed highly suggestive hemosiderin-laden masses. Hemosiderin was most clearly seen on gradient echo sequences. Magnetic resonance imaging was also useful for determining the distribution of lesions. Intravenous gadolinium provided no additional information. Arthroscopy allowed to collect biopsy specimens and to perform synovectomy when called for. In our opinion, after a physical examination and plain roentgenograms, magnetic resonance imaging and arthroscopy should both be performed to determine the extent of lesions and to allow histological diagnosis and synovectomy, respectively.

Intraarticular diffusion of Gd-DOTA after intravenous injection in the knee: MR imaging evaluation.

Intraarticular concentration of gadolinium tetraazacyclododecanetetraacetic acid (DOTA) after intravenous injection and the diagnostic contribution of the subsequent arthrographic effect were assessed for meniscal lesions in the knee. Kinetics were studied in three healthy volunteers. Passage of contrast material into the synovial fluid of the joint was evaluated in 53 knees by measuring the signal intensity on T1-weighted images before, immediately after, and 1 hour after injection. Synovial fluid enhancement was 1.46-fold greater than the unenhanced value after 10 minutes, plateaued after 30 minutes, and was 1.95-fold greater after 1 hour. In articular fluid samples from four patients 1 hour after intravenous injection, the average intraarticular concentration was 141 mumol +/- 47 (1 standard deviation) at atomic absorption spectrophotometry. Knee mobilization improved the passage of contrast material into the synovial fluid by approximately 120% at 10 minutes and 25% at 1 hour. In eight of 39 tears, unenhanced standard sequences were equivocal. In seven of these uncertain cases, delayed contrast-enhanced images permitted adequate interpretation. Intraarticular concentration of Gd-DOTA produces a sufficient arthrographic effect for meniscus evaluation.

Preoperative computed tomography for transhiatal esophagectomy.

We report the results of a retrospective evaluation of preoperative chest computed tomography (CT) in 50 consecutive patients with esophageal carcinoma confirmed surgically. Forty patients underwent transhiatal esophagectomy without thoracotomy. In ten cases, blunt dissection of the esophageal carcinoma was impossible because of involvement of an adjacent organ. Transhiatal esophagectomy carries lower morbidity and mortality rates than the standard thoracotomy procedure, although long-term survival is considered to be the same with either method. The overall sensitivity of CT in detecting involvement of an adjacent organ, thus contraindicating the transhiatal procedure, was 90%, with an overall specificity of 92%. The positive predictive value was 75%, and the negative predictive value 89%. The negative predictive value of CT for tracheobronchial invasion, the main surgical risk in the transhiatal procedure, was 90%. A negative preoperative CT appears to be a reliable indicator for patients undergoing transhiatal esophagectomy.

D-dimer and thrombin-antithrombin III complex levels uncorrelated with phlebographic findings in 11 total knee replacement patients.

D-dimer and thrombin-antithrombin III complex (TAT) were assayed in 11 patients at various times pre- and post-operatively in order to determine the possible value of these parameters in screening for thromboembolic complications. Phlebography revealed distal thrombosis in 6 of the 11 patients. The D-dimer level, already elevated before surgery, increased at day 1 and remained high at days 5 and 10. Two methods were used for the assays and showed strongly correlated results. The TAT level increased at day 1 and then progressively returned toward basal values. No difference was observed at any time between patients with or without thrombosis. The results in surgical patients undergoing knee replacement suggest that neither D-dimer nor TAT assays are valid screening procedures for post-operative DVT. Nevertheless, in view of the small number of patient studied, further work is required to confirm these results.

Monocyte procoagulant activity and membrane-associated D dimer after knee replacement surgery.

We have recently shown that monocyte membrane-associated cross-linked fibrin derivatives (D dimer) can be evidenced by immunogold staining. Using this method, the procoagulant activity (PCA) expressed in vitro by endotoxin-stimulated monocytes has been found to correlate significantly with the number of D dimer-positive monocytes. The incidence of postoperative thrombosis in patients undergoing total knee replacement has been reported by Stulberg et al to be 57%. Since monocytes can play a role, via increased PCA, in the activation of intravascular coagulation, we sought to determine the level of monocyte PCA ex vivo after knee replacement surgery and its possible correlation with the number of D dimer-positive monocytes. Finally, we examined the possible link between these modifications and the occurrence of postoperative deep vein thrombosis (DVT). The PCA expressed by monocytes with or without suboptimal stimulation, the number of D dimer-positive monocytes and the plasma level of D dimer were measured pre- and post-operatively in 11 patients undergoing total knee replacement. Phlebography was performed on day 10 after surgery. A significant increase in the PCA of stimulated monocytes was observed on day 10 after surgery. Moreover, both the number of D dimer-positive monocytes and the plasma level of D dimer increased significantly post-operatively. The number of D dimer-positive monocytes correlated with both monocyte PCA and the plasma D dimer level. The relation between these parameters is discussed. However, neither monocyte PCA nor the number of D dimer-positive monocytes was found to correlate with the occurrence of deep vein thrombosis.

[Diagnosis of glucagonoma. Value of scanning, echography and arteriography. Apropos of 2 cases and a review of the literature]. / Diagnostic du glucagonome. Intérêt du scanner, de l'échographie et de l'artériographie. A propos de deux observations et revue de la littérature.

The authors report two cases of glucagonoma, a rare endocrine tumor of the pancreas, and describe the data currently found in literature. Glucagonoma is a single and usually large tumor, which develops in the alpha cells of the islets of Langerhans and evolves slowly. The combination of characteristic skin lesions, diabetes and weight loss should lead to searching for hyperglucagonemia and for the pancreatic tumor. The diagnosis is usually made rather late, average evolution is five years before diagnosis when it is detected. Imaging, in particular ultrasound and computed tomography (CT), proves to be necessary for the positive diagnosis of glucagonoma as it localizes the pancreatic mass and plays a role in local assessment, thus providing guidance for surgery. The role of imaging is also fundamental for the detection of metastases, which are the only sign of malignancy as no criterion of benignity is found for this tumor.

[Endoscopically "impassable" urethral stenosis. Catheterization under fluoroscopic guidance. Apropos of 11 cases]. / Sténoses de l'urètre "infranchissables" par voie endoscopique. Cathétérisme sous guidage radioscopique. A propos de onze cas.

In eleven patients with impassable urethral stenoses, we attempted retrograde catheterisation with an angiographic guide under fluoroscopic control. The stenosis was able to be negotiated with the guide in 10 cases (91% success). After dilatation by dilators (coaxial or rigid) or by Olbert's angioplasty balloon, we were able to introduce a Foley catheter into the bladder. The only failure was caused by a very marked separation of the two ends of the urethra due to trauma. This simple and effective method constitutes an alternative to immediate surgical treatment of endoscopically impassable urethral stenoses.

[X-ray computed tomography in acute pancreatitis]. / La tomodensitométrie dans les pancréatites aiguës.

Diagnostic imaging of acute pancreatitis has been revolutionized by the introduction of computed tomography (CT). The purpose of this report is to review the different CT findings of the disease. The authors emphasize the predictive value of the contrast enhanced CT. It seems to be the most reliable method for detecting the most severe forms of acute pancreatitis and their complications. Correlation of CT findings with clinical and biological prognostic signs allows an easier surgical management.

[Muscle metastases: ultrasonic and x-ray computerized tomographic aspects. Apropos of 9 cases]. / Les métastases musculaires: aspects échographiques et tomodensitométriques. A propos de 9 observations.

Clinical, ultrasound and CT scan examinations were carried out in 9 patients with secondary muscle lesions. All muscles can be affected but there was a marked predominance of psoas lesions (6 of the 9 cases). Two contrasting clinical pictures are seen. Secondary muscle tumors can occur during evolution of a known treated cancer (5 of the 9 cases), revealed usually by large, rarely painful, mass. CT scan imaging shows a heterogeneous mass taking up contrast and often partially necrotic, the lesions appearing hypoechogenic or heterogeneous on ultrasound examination. Certain lesions can be totally necrotic. In some cases (4 of the 9 patients) the muscle metastases revealed the presence of a tumor. Symptomatology may be atypical and lead to a delay in diagnosis. Fine needle puncture biopsy can detect the secondary origin of the muscle lesion and also the primary tumor site (4 out of 9 cases), bronchopulmonary and colon cancer predominating. Images are however non-specific and in the absence of NMR imaging the muscle or lymph node metastases can be confused, although this has no practice consequences since treatment is identical.

Hepatitis tuberculosis presenting as tumoral disease on ultrasonography.

Macronodular involvement of the liver is a rare manifestation of hepatitis tuberculosis. Two cases of this pseudotumoral form are reported on ultrasonography, demonstrating multiple hypoechoic nodules distributed throughout the liver. The authors state the difficulty in differentiating this form in its atypical presentation from lymphomatous or secondary malignancies. They stress the importance of the bacteriological and/or histological diagnosis which can be performed with fine-needle percutaneous biopsy under ultrasound guidance and which allows effective therapy.

[Prognostic value of x-ray computed tomography in acute pancreatitis: contribution of the injection of intravenous contrast media]. / Valeur pronostique de la tomodensitométrie dans les pancréatites aiguës: apport de l'injection de produit de contraste intraveineux.

Thirty seven patients suffering from acute pancreatitis were explored using contrast-enhanced computed tomography (CT). The authors found a good concordance between the extension of the lesions on the initial CT examination, prognostic criteria on admission and the course of the disease. In addition, a new prognostic CT sign was reported in the early phase of parenchymal contrast perfusion, i.e. the lack of contrast-enhancement in a limited portion of the pancreas. This sign was present in 8 patients, all with severe clinical symptoms. These 8 patients showed the highest morbidity rate in the series with abscess-type complications occurring in all, compared with 24 p. 100 among the 29 other patients who did not exhibit this CT sign. Moreover, these 8 patients showed the highest mortality rate (25 p. 100 compared with 3.5 p. 100 among the other patients). An histological analysis of partial pancreatectomy specimens was performed in 7 out of the 8 patients. Devitalized pancreatic tissue, at the site of the parenchymal abnormalities on CT scan, was found in all cases. One false negative case was reported. Contrast-enhanced CT scan seems to be the most reliable method for diagnosing pancreatic necrosis during acute severe pancreatitis. It appears to be an useful prognostic predictor of morbidity. It can improve the outcome of the disease by depicting and guiding needle aspiration of a fluid collection, and/or surgery in case of clinical findings suggesting abscess formation.

[Complications of the treatment of renal calculi by extracorporeal lithotripsy. Prospective evaluation of 80 treated kidneys]. / Complications du traitement de la lithiase rénale par lithotriptie extracorporelle. Evaluation prospective de 80 reins traités.

The acute effects of extracorporeal shock wave lithotripsy (ESWL) on morphology and function of the kidney were prospectively evaluated by abdominal radiography, ultrasonography and contrast-enhanced computed tomography, in 80 treated kidneys. Two types of complications were demonstrated: 1. Obstruction of the ureter by stone fragments in 25% of cases. Relief procedures became necessary in 5 patients (6% of the 80 cases). 2. Limited injuries of the kidney and perirenal spaces in 44% of cases: parenchymatous abnormalities 17.5%; subcapsular hematoma 12.5%; perirenal fluid collection 24%. No treatment was necessary and morphologic abnormalities disappeared in one or two months post-ESWL. Severe ureteral obstruction after ESWL seems to be related to stone size. No definitive evidence that kidney's injury was related to the number of shock waves applied to the kidney was found.