Clinical aspects of ballistic peripheral nerve injury: shrapnel versus gunshot.

OBJECTIVES: Ballistic injuries to peripheral nerves pose special challenges in terms of indications, timing and type of surgical intervention. The aim of the present work was to analyze our experience in the surgical treatment of peripheral nerve ballistic injuries with respect to the mechanism of injury (gunshot versus shrapnel), and identify common and dissimilar prognostic factors in both types of injury. METHODS: This study was conducted on 42 patients totaling 58 nerves. Twenty-two patients (32 nerves) were injured by gunshot and 20 patients (26 nerves) by shrapnel. Median postoperative follow-up was 33 months (range 12 months to 14 years). RESULTS: Overall postoperative outcome appears to be more favorable for gunshot-wound (GSW) patients than shrapnel-injured patients, especially in terms of neuropathic pain relief (75 % vs. 58 % respectively, p < 0.05). Presence of foreign particles in shrapnel injured patients has a negative impact on the surgical outcome in terms of rate of pain improvement (28 % compared to 67 % in patients with and without foreign particles, respectively). Nerve graft reconstruction, rather than neurolysis, seems to be the more beneficial treatment for shrapnel-induced neuropathic pain (100 % vs. 47 % in improvement rate, respectively). Early surgical intervention (median 2 months after injury) significantly relieved neuropathic pain in 83 % of shrapnel-injured patients compared to 58 % in patients operated later. CONCLUSIONS: This study suggests that shrapnel injury is more destructive for nerve tissue than gunshot injury. Our impression is that early surgical intervention in shrapnel injuries and split nerve grafting (especially when small fragments are recognized in the nerve) significantly improve the patient's functional activity and quality of life.

Computed tomography colonography ("virtual colonoscopy") in Israel: results of the National CT Colonography Survey of the Israeli Association of Abdominal Imaging and the Israeli Radiological Association.

BACKGROUND: Computed tomographio colonography, also known as virtual colonoscopy, is a rapid, non-invasive imaging technique to detect colorectal masses and polyps that is becoming increasingly popular. OBJECTIVES: To evaluate the availability, technique, standards of performance and indications for CT colonography in Israel. METHODS: A questionnaire on CT colonography was sent to all radiology departments and private institutions that perform CTC in Israel. We evaluated multiple technical parameters regarding the performance and interpretation of CTC as well as radiologists' training and experience. RESULTS: Fourteen institutions--7 hospitals and 7 private clinics--participated in the study. Most of the small radiology departments and nearly all of the more peripheral radiology departments do not perform CTC studies. Since 2000 and until March 2007, a total of 15,165 CTC studies were performed but only 14% (2123 examinations) were performed at public hospitals and 86% (13,042 exams) at private clinics. CTC was performed after an incomplete colonoscopy or for various contraindications to endoscopic colonoscopy in up to a third of cases. In the various institutions patients were self-referred in 20-60% of cases, more commonly in private clinics. All CTC examinations were performed on 16-64 slice CT scanners and only a small minority was performed on 4-slice scanners in 2001. All but one center used low radiation protocols. Nearly all facilities used a 2 day bowel-cleansing protocol. All except one facility did not use stool tagging or computer-aided diagnosis. All facilities inflated the colon with room air manually. All institutions used state-of-the-art workstations, 3D and endoluminal navigation, and coronal multi-planar reconstructions routinely. There are 18 radiologists in the country who perform and interpret CTC studies; half of them trained abroad. Ten of the radiologists (56%) have read more than 500 CTC studies. CONCLUSIONS: In Israel, CTC examinations are performed by well-trained and highly experienced radiologists using the latest CT scanners and workstations and adhering to acceptable CTC guidelines.

Vascular and biliary abnormalities mimicking cholangiocarcinoma in patients with cavernous transformation of the portal vein: role of color Doppler sonography.

OBJECTIVE: The purpose of this study was to describe and evaluate the sonographic and color Doppler features of tumorlike biliary and venous changes in patients with cavernous transformation of the portal vein (CTPV). METHODS: The sonographic studies of 24 patients with CTPV were reviewed. Sonographic evaluation of the biliary system included measurement of intrahepatic and extrahepatic biliary duct caliber changes and common bile duct (CBD) wall thickening and character. Color Doppler features of the portoportal collateral circulation at various locations (intrahepatic, periportal, gallbladder, pancreatic, and gastric regions) were carefully evaluated. RESULTS: Biliary abnormalities were detected in 13 (54%) of 24 patients with CTPV. All 13 patients (100%) had intrahepatic biliary dilatation; 11 patients (85%) had CBD abnormalities: diffuse CBD wall thickening causing diffuse narrowing of the true lumen in 7 (54%) and CBD dilatation proximal to the focal area of narrowing due to pericholedochal compressing venous collaterals in 4 (30%). A tumorlike solid mass appeared on the gray scale images of 2 patients (8%): 1 at the porta hepatis and the other at the pancreatic head level. Color Doppler imaging evaluation showed venous-type flow, suggesting a bulk of varicosities. CONCLUSIONS: Portoportal collaterals in patients with CTPV may alter the biliary and venous systems, causing biliary wall thickening, stenosis, intrahepatic and extrahepatic dilatation, and pseudotumors. Detailed sonographic and color Doppler imaging assessment can show and facilitate the correct diagnosis of those changes, thus avoiding the need for a more invasive modality such as endoscopic retrograde cholangiopancreatography or a more expensive investigation such as magnetic resonance cholangiopancreatography.

Percutaneous drainage as the treatment of choice for neonatal ovarian cysts.

BACKGROUND: Involution of neonatal ovarian cysts occurs usually by 12 months. Persisting cysts larger than 4 cm are prone to torsion. Two modes of therapy are advocated: surgery and percutaneous US-guided cyst aspiration. OBJECTIVE: To compare ovarian preservation following the use of US-guided aspiration or conventional surgery for the treatment of large asymptomatic neonatal ovarian cysts, and to suggest alternative treatment when intrauterine ovarian torsion occurs. MATERIALS AND METHODS: The study population comprised 25 baby girls with an ovarian cyst, 5 with a simple cyst and 20 with a complex cyst. Of these 25 infants, 8 had surgery and 17 had US-guided cyst aspiration. RESULTS: In the surgical group of 8, 6 underwent oophorectomy, and in 2 the ovary was saved. In the aspirated group of 17, the ovary was saved in 10, and was lost in 5. At the time of this report one patient was still in the follow-up period, and one was lost to follow-up. CONCLUSION: US-guided aspiration of large neonatal cysts preserves ovarian tissue in a higher percentage of patients than surgery. It is safe, effective, and repeatable. We recommend US-guided aspiration of asymptomatic large ovarian cysts for salvage or for decompression if intrauterine ovarian torsion occurs. Surgery should be reserved for patients with acute torsion, intestinal obstruction and intestinal volvulus.

Modification of surgical planning based on cardiac multidetector computed tomography in reoperative heart surgery.

BACKGROUND: Repeat open heart surgery is associated with an increased risk of injury to old conduits and cardiac structures. To reduce this risk, we evaluated the contribution of multidetector computed tomography angiography in planning repeat cardiac operations. METHODS: Fifteen patients who had previous coronary artery bypass grafting procedures underwent retrospective-gated computed tomographic angiography with a 16-slice multidetector computed tomography. Relation of the grafts to the expected median sternotomy line, graft patency and anatomic course, possible aortic cannulation and cross-clamp sites, distances between the right ventricle to the sternum, and calcification of the ascending aorta were assessed. RESULTS: Multidetector computed tomography demonstrated 45 conduits (mean, 3 +/- 1.1); 18 arterial grafts and 13 saphenous vein grafts that were patent, and 2 internal mammary artery grafts and 12 saphenous vein grafts that were occluded. Significant narrowing was shown in 3 of the patent internal mammary arteries and 4 of the patent saphenous vein grafts. Adherence of the right ventricle, left internal mammary artery, and saphenous vein graft to the sternum (0 to 3 mm in the midline) was demonstrated in 8, 2, and 1 patients, respectively. Two patients had a heavily calcified aorta. During surgery, all multidetector computed tomographic findings were confirmed. Three aspects of the operative plans of 4 patients were modified according to multidetector computed tomographic findings: median sternotomy approach (3 patients), cannulation site (2 patients), and myocardial preservation technique (3 patients). On the basis of multidetector computed tomographic evaluations, surgery was cancelled in 2 patients in whom repeat operation was judged to be associated with increased risk: 1 patient, scheduled for coronary artery bypass grafting, had an extremely calcified aorta, and the other, scheduled for aortic valve replacement, had grafts that were adherent to the sternum. CONCLUSIONS: Multidetector computed tomography is a new noninvasive tool for three-dimensional preoperative assessment of complex cardiac and graft anatomy. Our initial experience suggests that it may provide information to warrant modifying surgical planning, thus contributing to the safety of reoperative heart surgery.

Radiographic manifestations of normal postoperative anatomy and gastrointestinal complications of bariatric surgery, with emphasis on CT imaging findings.

Recently, there has been a tremendous increase in the frequency of utilization of surgery to control morbid obesity that is very common and increasing in incidence in Western industrialized nations. Imaging plays an important role in the evaluation and management of patients before and after bariatric surgery. In this article, we discuss the imaging findings relating to bariatric procedures, focusing on the role of computed tomography (CT) in the evaluation of normal postoperative anatomy and gastrointestinal complications.

Further development of reconstructive and cell tissue-engineering technology for treatment of complete peripheral nerve injury in rats.

UNLABELLED: In this work we evaluated the efficacy of biodegradable composite co-polymer guiding neurotube, based on tissue-engineering technology, for the treatment of complete peripheral nerve injury where the nerve defect is significant. The right sciatic nerve of 12 three-month-old rats was completely transected and peripheral nerve segment was removed. A 2.2-cm biodegradable co-polymer neurotube containing viscous gel (NVR-N-Gel) with survival factors, neuroprotective agents and Schwann cells was placed between the proximal and the distal parts of the transected nerve for reconnection a 2-cm nerve defect. The proximal and distal parts of the nerve were fixed into the neurotube using 10-0 sutures. Ultrasound observation showed growth of the axons into the composite neurotube 2 months after the surgery. Electrophysiological study indicated compound muscle action potentials in nine out of 12 rats, 2-4 months after peripheral nerve reconstructive surgery. The postoperative follow-up (up to 4 months) on the operated rats that underwent peripheral nerve reconstruction using composite co-polymer neurotube, showed beginning of re-establishment of active foot movements. The tube was dissolved and nerve showed complete reconnection. Histological observation of the nerve showed growth of myelinated axons into the site where a 2-cm nerve defect replaced by composite co-polymer neurotube and into the distal part of the nerve. IN CONCLUSION: (1) an innovative composite neurotube for reconstruction of significant loss of peripheral nerve segment is described; (2) a viscous gel, containing survival factors, neuroprotective agents and Schwann cells served as a regenerative environment for repair. Further investigations of this reconstructive procedure are being conducted.

Sonographic evaluation of brachial plexus pathology.

Pre-operative US examinations of the brachial plexus were performed with the purpose of exploring the potential of this technique in recognizing lesions in the region and defining their sonographic morphology, site, extent, and relations to adjacent anatomic structures, and comparing them to the surgical findings to obtain maximal confirmation. Twenty-eight patients with clinical, electro-conductive, and imaging findings suggestive of brachial plexus pathology were included in this study. There were four main etiology groups: post-traumatic brachial plexopathies; primary tumors (benign and malignant); secondary tumors; and post irradiation injuries. Twenty-one of the 28 patients underwent surgery. Advanced imaging (mostly MRI) served as an alternative gold standard for confirmation of the findings in the non-surgically treated group of patients. The US examinations were performed with conventional US units operating at 5- to 10-MHz frequencies. The nerves were initially localized at the level of the vertebral foramina and then were followed longitudinally and axially down to the axillary region. Abnormal US findings were detected in 20 of 28 patients. Disruption of nerve continuity and focal scar tissue masses were the principal findings in the post-traumatic cases. Focal masses within a nerve or adjacent to it and diffuse thickening of the nerve were the findings in primary and secondary tumors. Post-irradiation changes presented as nerve thickening. Color Doppler was useful in detecting internal vascularization within masses and relation of a mass to adjacent vessels. The eight sonographically negative cases consisted either of traumatic neuromas smaller than 12 mm in size and located in relatively small branches of posterior location or due to fibrotic changes of diffuse nature. Sonography succeeded in depicting a spectrum of lesions of traumatic, neoplastic, and inflammatory nature in the brachial plexus. It provided useful information regarding the lesion site, extent, and anatomic relationships; thus, the principal aims of the study were therefore met. Once the technique of examination is mastered, sonography should be recommended as part of the pre-operative evaluation process post-ganglionic brachial plexus pathology. Most disadvantages are related to the restricted field of view and inability to overcome bonny obstacles particularly in evaluating pre-ganglionic region. As sonography is frequently employed for investigation of the supraclavicular region, awareness of the radiologist to the findings described may enable the early recognition of pathologies involving or threatening to involve the brachial plexus.

[Left paraduodenal hernia: a report of a case and a review of clinical and diagnostic CT findings].

Internal hernias are an uncommon cause of small bowel obstruction. Paraduodenal hernias have been considered until recently the most common sub-type. Due to non-specific and intermittent signs and symptoms the diagnosis of these hernias is notoriously difficult. We report a case of a paraduodenal hernia diagnosed correctly with abdominal computed tomography that was confirmed at surgery and review the clinical and imaging findings of these hernias.

Cystic appearance of cervical lymph nodes is characteristic of metastatic papillary thyroid carcinoma.

PURPOSE: The usefulness of high-resolution sonography in diagnosing cervical lymph node metastases from papillary thyroid carcinoma was investigated. The accuracy of a particular sign, cystic change within a node, in establishing the diagnosis was assessed. METHODS: The sonographic findings in 63 patients with enlarged cervical lymph nodes were retrospectively reviewed. The patients had undergone high-resolution gray-scale and color Doppler sonography followed by ultrasound-guided fine-needle aspiration (FNA) in all patients and surgical excision in 27 patients. RESULTS: Abnormal sonographic features were present in the lymph nodes of all 63 patients. In 14 (70%) of 20 patients with papillary thyroid carcinoma, sonography depicted cystic changes. This pattern was not found in any of the other 43 patients, in whom FNA revealed either metastasis from another malignancy (22 patients) or benign reactive lymphadenopathy (21 patients). Among the 63 patients, there were 43 true-negative, 14 true-positive, 6 false-negative, and no false-positive results in the diagnosis of metastatic papillary thyroid carcinoma using the presence or absence of an intranodal cystic area on sonography. These results yielded a 70% sensitivity, 100% specificity, 100% positive predictive value, 88% negative predictive value, and 90% overall accuracy for this criterion. CONCLUSIONS: Cystic changes within a cervical lymph node are highly suggestive of metastatic papillary thyroid carcinoma.

Delineating gray and white matter involvement in brain lesions: three-dimensional alignment of functional magnetic resonance and diffusion-tensor imaging.

OBJECT: The role of functional magnetic resonance (fMR) imaging has become increasingly important in the presurgical mapping of gray matter. Neurosurgical interventions often involve fiber bundles that connect critical functional areas. Recently, diffusion-tensor (DT) imaging has enabled the visualization of fiber bundle direction and integrity, thus providing the ability to delineate clearly white matter from gray matter tissue. The main objective of this study was to improve the presurgical assessment of critical functionality in the vicinity of brain lesions by combining DT and fMR imaging methodologies. METHODS: Twenty patients with various space-occupying brain lesions underwent imaging for presurgical evaluation of motor and/or somatosensory functions. The authors focus on five patients with diverse space-occupying brain lesions. Diffusion tensor-based fiber tracking and fMR imaging activation maps were superimposed in three dimensions to visualize pyramidal tracts corresponding to motor and somatosensory regional activation. CONCLUSIONS: The combination of DT and fMR imaging for presurgical functional brain mapping provides valuable information that cannot be extracted using either method alone. The validity and sensitivity of noninvasive functional mapping for surgical guidance could be improved by considering results obtained with both methods. Furthermore, the use of three-dimensional visualization seems crucial and unique for viewing and understanding the complicated spatial relationship among the lesion, gray matter activation, and white matter fiber bundles.

Brachial plexus sonography: a technique for assessing the root level.

OBJECTIVE: Our study was intended to establish a technique to assess the level of the roots of the brachial plexus using high-resolution sonography. MATERIALS AND METHODS: The skeleton of a cervical spine was examined in vitro to determine whether the vertebrae may be identified individually on sonography by means of the evaluation of their transverse processes. Then 20 healthy subjects and five patients who had undergone CT of the cervical spine were evaluated sonographically, and we attempted to identify the level of individual roots of the brachial plexus using the transverse processes as landmarks. To establish the reliability of this method, a blinded review of sonograms of the paravertebral area obtained at various levels was performed independently by three examiners. RESULTS: In vitro, sonography was reliable in depicting the level of the C7 vertebra because of the absence of the anterior tubercle from its transverse processes. In healthy subjects, this feature allowed us to establish the level of the roots outside the spine. In our series, the C4-C7 roots were visible sonographically in all cases, whereas the C8 and T1 levels were seen, respectively, in only 16 of 20 and eight of 20 cases. All examiners correctly identified the C7 level in the blinded review of sonograms. CONCLUSION: High-resolution sonography can reveal the level of the roots of the brachial plexus on the basis of the different morphology of the transverse processes of the vertebrae. Our study has implications for confirming the exact level of pathologic roots before surgery.

Minimally invasive techniques in the treatment of liver tumors.

BACKGROUND: Despite advances in cancer therapy the treatment of liver tumors remains a challenge. Most patients are poor candidates for surgical resection; both chemotherapy and irradiation have a low success rate and neither is without complications. New minimally invasive techniques for ablation of unresectable tumors have gained attention as effective treatment alternatives. Among these are percutaneous ethanol injection and radiofrequency ablation; both are effective for primary liver tumors and RFA is also effective for hepatic metastases. OBJECTIVE: To report our experience with PEI and RFA in the treatment of hepatic lesions. METHODS: The study included 49 lesions in 27 patients: 23 primary lesions in 13 patents treated with PEI and 26 lesions (22 secondary and 4 primary) in 14 patients treated with RFA. PEI was performed on an outpatient basis in the ultrasound suite; RFA was done in hospitalized patents (9 in the ultrasound suite and 4 in the operating room). Patients were followed with triphasic spiral computerized tomography 1 month after treatment and every 3-6 months thereafter. RESULTS: Complete necrosis was achieved with PEI on the first attempt in 11 of 23 primary lesions (91.3%). In 8.7% (2/23) a second series of treatments was required. Using RFA, complete necrosis was achieved in 85% of lesions (22/26) and partial necrosis in 15% (4/26). Complications included low fever (3 patients), high fever and abscess formation (1 patient), peri-tumoral necrosis (1 patient) and portal vein thrombosis (1 patient). CONCLUSIONS: Our preliminary results confirm that PEI and RFA are an effective and safe option for treating hepatic tumors in patients unfit for surgery.