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Kimberly K Amrami

Publications and source records attributed to Kimberly K Amrami.

At least 19 recordsLinked to original sources
PubMed2007

Anatomic compartments of the foot: a 3-Tesla magnetic resonance imaging study.

There is neither consensus on the number nor agreement on the location of the anatomic compartments of the foot. This project utilized high-resolution magnetic resonance imaging (MRI) to identify foot compartments. The purpose of this study was to devise a new system using 3-Tesla (3T) MRI that assessed the number and location of these compartments. Six feet from healthy volunteers were imaged. From these, 10 compartments were described: (1) medial, (2) calcaneal, (3) lateral, (4) central superficial, (5) central deep (adductor), (6-9) interossei, and (10) skin. The 3T MRI and foot/ankle coil allowed us to assess the number and location of foot compartments.

Compartment Syndromes↗
PubMed2006

The clinico-anatomic explanation for tibial intraneural ganglion cysts arising from the superior tibiofibular joint.

OBJECTIVE: To demonstrate that tibial intraneural ganglia in the popliteal fossa are derived from the posterior portion of the superior tibiofibular joint, in a mechanism similar to that of peroneal intraneural ganglia, which have recently been shown to arise from the anterior portion of the same joint. DESIGN: Retrospective clinical study and prospective anatomic study. MATERIALS: The clinical records and MRI findings of three patients with tibial intraneural ganglion cysts were analyzed and compared with those of one patient with a tibial extraneural ganglion cyst and one volunteer. Seven cadaveric limbs were dissected to define the articular anatomy of the posterior aspect of the superior tibiofibular joint. RESULTS: The condition of the three patients with intraneural ganglia recurred because their joint connections were not identified initially. In two patients there was no cyst recurrence when the joint connection was treated at revision surgery; the third patient did not wish to undergo additional surgery. The one patient with an extraneural ganglion had the joint connection identified at initial assessment and had successful surgery addressing the cyst and the joint connection. Retrospective evaluation of the tibial intraneural ganglion cysts revealed stereotypic features, which allowed their accurate diagnosis and distinction from extraneural cases. The intraneural cysts had tubular (rather than globular) appearances. They derived from the postero-inferior portion of the superior tibiofibular joint and followed the expected course of the articular branch on the posterior surface of the popliteus muscle. The cysts then extended intra-epineurially into the parent tibial nerves, where they contained displaced nerve fascicles. The extraneural cyst extrinsically compressed the tibial nerve but did not directly involve it. All cadaveric specimens demonstrated a small single articular branch, which derived from the tibial nerve to the popliteus. The branch coursed obliquely across the posterior surface of the popliteus muscle before innervating the postero-inferior aspect of the superior tibiofibular joint. CONCLUSIONS: The clinical, MRI and anatomic features of tibial intraneural ganglion cysts are the posterior counterpart of the peroneal intraneural ganglion cysts arising from the anterior portion of the superior tibiofibular joint. These predictable features can be exploited and have implications for the pathogenesis of these intraneural cysts and treatment outcomes. These ganglion cysts are joint-related and provide further evidence to support the unifying articular theory. In each case the joint connection needs to be identified preoperatively, and the articular branches and the superior tibiofibular joint should be addressed operatively to prevent cyst recurrence.

Adult↗
PubMed2006

Coexisting secondary intraneural and vascular adventitial ganglion cysts of joint origin: a causal rather than a coincidental relationship supporting an articular theory.

OBJECTIVE: To introduce the clinical entity of an intraneural ganglion cyst coexisting with a vascular adventitial cyst arising from the same joint. DESIGN: Retrospective review. PATIENTS: Two patients presented with predominantly deep peroneal neuropathy due to complex superior tibiofibular joint-related cysts. In addition to having peroneal intraneural ganglion cysts, these patients had vascular adventitial cysts: one involving a capsular arterial branch, the other a capsular vein [as well as a large, recurrent, intramuscular (extraneural) ganglion]. We then reviewed MRIs of 12 other consecutive cases of intraneural ganglia (10 peroneal and 2 tibial) arising from the superior tibiofibular joint that we treated, as well as other reported cases in the literature to determine if there were other (unrecognized) examples supporting the combination of clinical findings and radiographic patterns. RESULTS: Retrospective analysis of MRIs in the two surgically proven cases of peroneal intraneural ganglia with vascular adventitial cyst extension showed a common imaging pattern that we have termed "the wishbone sign," consisting of the connection of the ascending limb of the peroneal intraneural ganglion and the longitudinal limb of the vascular adventitial cyst in the axial plane. Our review suggests that vascular adventitial cyst extension occurs in a large proportion of cases of peroneal intraneural ganglia. A similar growth pattern was noted in a case of a tibial intraneural ganglion. CONCLUSIONS: The combination of intraneural and vascular adventitial cysts is understandable given our knowledge of normal and pathologic anatomy of para-articular cysts. The combination of intraneural ganglia and vascular adventitial cysts broadens the spectrum of clinical presentations of these cysts and suggests that cysts and their content can dissect from a joint along neurovascular bundles. These cases provide important evidence to support the articular theory for the pathogenesis of not only neural but vascular adventitial cysts as well.

Diagnosis, Differential↗
PubMed2006

Screening mammograms: interpretation with computer-aided detection--prospective evaluation.

PURPOSE: To prospectively determine the effect of a commercially available computer-aided detection (CAD) system on interpretations of screening mammograms. MATERIALS AND METHODS: Institutional review board approval was granted; informed consent and HIPAA compliance were waived. A total of 21 349 screening mammograms obtained in 18 096 women were interpreted first without and then with review of CAD images to determine the effect of CAD analysis on the screening breast cancer detection rate, recall rate, and positive predictive value (PPV) for biopsy. The percentage of total cancers detected by the radiologists independent of CAD and the percentage correctly marked by the CAD system were determined. RESULTS: On the basis of pre-CAD interpretations, 2101 patients were recalled for diagnostic evaluation, 256 biopsies were performed, and 105 breast cancers were diagnosed. The breast cancer detection rate per 1000 screening mammograms was 4.92 (105 of 21 349 mammograms), the recall rate was 9.84% (2101 of 21 349 mammograms), and the PPV for biopsy was 41.0% (105 of 256 biopsies). After CAD image review, 199 additional patients were recalled, 21 additional biopsies were performed, and eight additional cancers were detected. The effect was a 7.62% (eight of 105) increase in the number of breast cancers detected, an increase in the recall rate to 10.77% (2300 of 21 349 mammograms), and a slight decrease in the PPV to 40.8% (113 of 277 biopsies). Radiologists detected 92.9% (105 of 113 cancers) of the total cancers, and CAD correctly marked 76.1% (86 of 113 cancers). CONCLUSION: The use of CAD improved the detection of breast cancer, with an acceptable increase in the recall rate and a minimal increase in the number of biopsies with benign results.

Adult↗
PubMed2006

Application of three-dimensional rendering in joint-related ganglion cysts.

The origin of para-articular cysts is poorly understood and controversial. The relatively common, simple (extraneural) cysts are presumed to be derived from joints, although joint connections are not always established. Rarer complex cysts are thought by many to form de novo within nerves (intraneural ganglion cysts) or within vessels (adventitial cysts) (degenerative theory). We believe that these simple and complex ganglion cysts are joint-related (articular theory). Joint connections are often not readily appreciated with routine imaging or at surgery. Not identifying and/or treating joint connections frequently leads to cyst recurrence. More sophisticated imaging may enhance visualization of these joint connections. We created a 3D rendering technique to assess potential joint connections of simple and complex cysts localized to the knee and superior tibiofibular joints in patients with fibular (peroneal) neuropathy. Two- and three-dimensional data sets from MRI examinations were segmented semiautomatically by signal intensity with further refinement based on interaction with the user to identify specific anatomic structures, such as small nerves and vessels on serial images. The bone, cysts, nerves, and vessels were each assigned different color representations, and 3D renderings were created in ANALYZE using the data sets closest to isotropic (voxel with equal length in all dimensions) resolution as the primary background rendering. We selected four cases to illustrate the spectrum of pathology. In all of these cases, we demonstrated joint connections and correlated imaging and operative findings. Surgery addressing the cyst and the joint connection resulted in excellent outcomes; postoperative MRIs done more than 6 months later confirmed that there was no recurrence. In addition to highlighting the important relationship of these cysts to neighboring anatomic structures, this 3D technique allows visualization of "occult" connections not readily appreciated with standard MR imaging. We believe that these joint-related cysts have a common pathogenesis; they dissect through a capsular rent and follow the path of least resistance; they may form simple cysts by dissecting out into the soft tissue, or more complex cysts by dissecting within the epineurium of nerves or adventitia of vessels (along an articular branch), or various combinations of all of these types of cysts. Understanding the pathogenesis for cyst formation will improve surgical management and outcomes. We have adapted this 3D technique to enhance the visualization of cysts occurring at other joints.

Adult↗
PubMed2006

Neoplastic lumbosacral radiculoplexopathy in prostate cancer by direct perineural spread: an unusual entity.

Neoplastic lumbosacral plexopathy occurs with some abdominal and pelvic malignancies. Patients present with severe pain radiating from the low back down to the lower extremities, and this progresses to weakness. Neoplastic lumbosacral plexopathy is virtually always associated with known malignancy or obvious pelvic metastatic disease. Uncommonly, prostate cancer can present as a lumbosacral plexopathy occurring through direct pelvic spread. We describe two cases of lumbosacral radiculoplexopathy from infiltrative prostate cancer without evidence of other pelvic or extraprostatic spread. The probable etiology of tumor spreading along prostatic nerves into the lumbosacral plexus (i.e., perineural spread) is discussed as are the potential mechanisms for this unusual mode of cancer dissemination.

Aged↗
PubMed2006

Isolated amyloidosis presenting with lumbosacral radiculoplexopathy: description of two cases and pathogenic review.

In this study, we present two cases of infiltrative, localized amyloidosis involving lumbosacral root and plexus, e.g., isolated amyloidomas. Rare and poorly understood amyloidomas may occur in both neurologic and non-neurologic tissues. The described cases emphasize potential for localized peripheral amyloidomas: (1) potential for associated lambda light chain lymphoplasmacytic lymphoma association; (2) e isolated amyloidosis without evidence for systemic plasma cell dyscrasia; (3) features suggestive of potential pathogenesis; and (4) discussion of treatment options including immunotherapy and resection. The limited literature and experience among other cases is described.

Aged↗
PubMed2006

Cystic transverse limb of the articular branch: a pathognomonic sign for peroneal intraneural Ganglia at the superior tibiofibular joint.

OBJECTIVE: The preoperative diagnosis of peroneal intraneural ganglia has been difficult to establish, and superior tibiofibular joint connections may not be identified. Misdiagnosis leads to incomplete treatment in that the articular branch connection may not be addressed, which can result in cyst recurrences. METHODS: We analyzed 20 surgically confirmed cases of paraarticular cysts arising from the superior tibiofibular joint to assess for joint connections and to determine common magnetic resonance imaging characteristics in intraneural ganglia that would allow distinction from extraneural ganglia. We identified and tested three radiographic signs describing the cysts and analyzed cyst morphology (i.e., size, shape, pattern), muscle compartments affected (i.e., for denervation), and neighboring joints (for associated pathology). RESULTS: Twelve cases of peroneal intraneural ganglia and eight cases of extraneural ganglia were connected to the superior tibiofibular joint. Retrospective review confirmed that these cysts were frequently misdiagnosed, and joint connections often were not recognized. The magnetic resonance imaging appearance of peroneal intraneural ganglia was stereotypical. These intraneural ganglia were tubular, whereas the extraneural were more mass-like. The tail sign was 100% sensitive for identifying joint connections but could not distinguish between intra- and extraneural cysts. The "transverse limb" sign (cystic material within the portion of the articular branch traversing the anterior surface of the fibula) was present in all cases of peroneal intraneural ganglia and none of the extraneural ganglia. The signet ring sign (the eccentric displacement of fascicles by cyst within the epineurium) was 100% sensitive for peroneal intraneural ganglia and 86% specific (it did not identify two cysts that did not extend more proximally into the common peroneal nerve). There was 100% interobserver concordance between the prospective interpretations by a single, blinded, radiologist and a trained first-year medical student with intraoperative findings. In this series, muscle denervation was more common and more pronounced in the intraneural than extraneural ganglia. Abnormalities in neighboring joints were noted nearly universally. CONCLUSION: This article demonstrates reproducible magnetic resonance imaging features that will easily allow one to identify the joint connection (the tail sign) in paraarticular cysts and also to distinguish between peroneal intraneural and extraneural ganglia (the transverse limb sign and the signet ring sign) at the superior tibiofibular joint with accuracy and confidence and with subsequent improvement in treatment and patient outcomes.

Adult↗
PubMed2006

Contiguous conventional and plexiform schwannomas. Report of two cases.

The authors present clinical, imaging, and histological features of two adult patients found to harbor a conventional schwannoma contiguous with a deep plexiform schwannoma. One patient had neurofibromatosis (NF) Type 2 (NF2), and both intracranial (bilateral oculomotor, trigeminal, acoustic, and hypoglossal schwannomas as well as meningiomas) and intraspinal (schwannomas and meningiomas) lesions. The proximal forearm lesions consisted of a conventional schwannoma and an underlying plexiform component. The second patient, who did not have NF2, presented with a similar enlarging mass in the distal arm; two contiguous lesions were resected. Both patients exhibited distinct, readily identifiable, magnetic resonance imaging features. Plexiform schwannomas are rare lesions that occur sporadically or, on occasion, in association with NF2 or meningiomas with or without multiple schwannomas. The authors believe that a more careful examination of patients with NF2 may show that these people have a higher incidence of plexiform schwannoma than previously thought. Pathological confirmation is crucial in distinguishing plexiform schwannomas from plexiform neurofibromas, because the latter are directly associated with NF1 and have a significant tendency to undergo malignant transformation. To the best of the authors' knowledge, this is the first report of a conventional schwannoma contiguous with a deep plexiform schwannoma.

Adult↗
PubMed2006

Suprascapular intraneural ganglia and glenohumeral joint connections.

OBJECT: Unlike the more commonly noted paralabral cysts (extraneural ganglia), which are well known to result in suprascapular nerve compression, only four cases of suprascapular intraneural ganglia have been reported. Because of their rarity, the pathogenesis of suprascapular intraneural ganglia has been poorly understood and a pathoanatomical explanation has not been provided. In view of the growing literature demonstrating strong associations between paralabral cysts and labral (capsular) pathology, joint connections, and joint communications, the authors retrospectively reviewed the magnetic resonance (MR) imaging studies and postoperative results in the two featured patients to test a hypothesis that suprascapular intraneural ganglia would have analogous findings. METHODS: Two patients who presented with suprascapular neuropathy were found to have intraneural ganglia. Connections to the glenohumeral joint could be established in both patients through posterior labrocapsular complex tears. In neither patient was the joint connection identified preoperatively or intraoperatively, and cyst decompression was performed by itself without attention to the labral tear. The suprascapular intraneural ganglia extended from the glenohumeral joint as far proximally as the level of the nerves' origin from the upper trunk in the supraclavicular fossa. Although both patients experienced symptomatic improvement after surgery, neurological recovery was incomplete. In both cases, postoperative MR images revealed cyst persistence. In addition, previously unrecognized superior labral anteroposterior (SLAP) Type II lesions (tears of the superior labrum extending anteroposterior and involving the biceps anchor at the labrum without actual extension into the tendon) were visualized. In one patient with a persistent cyst, an MR arthrogram was obtained and demonstrated a communication between the joint and the cyst. CONCLUSIONS: The findings in these two patients support the synovial theory for intraneural ganglia. Based on their experience with intraneural ganglia at other sites, the authors believe that suprascapular intraneural ganglia arise from the glenohumeral joint, egress through a superior (posterior) labral tear, and dissect within the epineurium along an articular branch into the main nerve, following the path of least resistance. Furthermore, these two cases of intraneural ganglia with SLAP lesions are directly analogous to the many cases of paralabral cysts associated with these types of labral tears. By better understanding the origin of this unusual type of ganglia and drawing analogies to the more common extraneural cysts, surgical strategies can be formulated to address the underlying pathoanatomy, improve operative outcomes, and prevent recurrences.

Adult↗
PubMed2005

The use of MR arthrography to document an occult joint communication in a recurrent peroneal intraneural ganglion.

The pathogenesis of intraneural ganglia remains controversial. Only half of the reported cases of the most common type, the peroneal nerve at the fibular neck, have been found to have pedicles connecting the cysts to neighboring joints detected with preoperative imaging or intraoperatively. We believe that all intraneural ganglia arise from joints, and that radiologists and surgeons need to look closely preoperatively and intraoperatively for connections. Not identifying these connections with imaging and surgical exploration has led not only to skepticism about an articular origin of the cyst, but also to a high recurrence rate after surgery. We present a patient who had two recurrences of a peroneal intraneural ganglion in whom a joint connection was not detected on previous MRIs and operations. Reinterpretation of the original films and high-resolution MRI demonstrated an "occult" joint connection to the superior tibiofibular joint. MR arthrography performed after exercise and 1 h delay, however, clearly showed the connection and communication. The joint connection was then confirmed at surgery through an articular branch. Postoperatively the patient regained nearly normal neurologic function, and follow-up MRI showed no cyst recurrence. MR arthrography with delayed imaging should be considered in cases of intraneural ganglia when a joint connection is not obvious on MRI.

Adult↗
PubMed2005

Lipomatosis of the sciatic nerve: typical and atypical MRI features.

Lipomatosis of nerve, also known as fibrolipomatous hamartoma, is a rare condition of nerve, usually affecting the median nerve. The MRI appearance is characteristic. We describe two cases of lipomatosis of nerve involving the sciatic nerve, an extremely unusual location for this lesion, in patients with sciatic neuropathy. These cases share the typical features previously described in the literature for other nerves, but also contain atypical features not previously highlighted, relating to the variability in distribution and extent of the fatty deposition. Recognition of the MRI appearance of this entity is important in order to avoid unnecessary attempts at surgical resection of this lesion.

Adult↗
PubMed2005

Imaging the brachial plexus.

Imaging the brachial plexus is challenging because of the complex anatomy of the region and the wide variety of pathology that can affect it. For the purpose of imaging, it is helpful to divide traumatic and nontraumatic entities affect-ing the brachial plexus. Improvements in imaging technology, including multidetector CT for CT myelography and the availability of full-field-strength MRI systems with fast gradients and dedicated surface coils for optimal spatial resolution, have led to more accurate prospective diagnoses and improved aid for neurosurgical planning for traumatic and nontraumatic brachial plexopathies. CT myelography is the current gold standard for the diagnosis of nerve root avulsions affecting the brachial plexus. MRI is the preferred modality for nontraumatic brachial plexopathy. Other modalities, such as US and PET, have a limited role in the evaluation of brachial plexus pathology. High-quality, high-resolution CT and MRI remain the mainstays for imaging the brachial plexus.

Brachial Plexus↗
PubMed2005

Adding in vivo quantitative 1H MR spectroscopy to improve diagnostic accuracy of breast MR imaging: preliminary results of observer performance study at 4.0 T.

PURPOSE: To determine whether the addition of in vivo quantitative hydrogen 1 (1H) magnetic resonance (MR) spectroscopy can improve the radiologist's diagnostic accuracy in interpreting breast MR images to distinguish benign from malignant lesions. MATERIALS AND METHODS: The study was approved by the institutional review board and, where appropriate, was compliant with the Health Insurance Portability and Accountability Act. All patients provided written informed consent. Fifty-five breast MR imaging cases-one lesion each in 55 patients aged 24-66 years with biopsy-confirmed findings-were retrospectively evaluated by four radiologists. Patients were examined with contrast material-enhanced fat-suppressed T1-weighted 4.0-T MR imaging. The concentration of total choline-containing compounds (tCho) was quantified by using single-voxel 1H MR spectroscopy. For each case, the radiologists were asked to give the percentage probability of malignancy, the Breast Imaging and Reporting Data System category, and a recommendation for patient treatment. Two interpretations were performed for each case: The initial interpretation was based on the lesion's morphologic features and time-signal intensity curve, and the second interpretation was based on the lesion's morphologic features, time-signal intensity curve, and tCho concentration. Receiver operating characteristic (ROC), Wilcoxon signed rank, kappa statistic, and accuracy (based on the area under the ROC curve) analyses were performed. RESULTS: Of the 55 lesions evaluated, 35 were invasive carcinomas and 20 were benign. The addition of 1H MR spectroscopy resulted in higher sensitivity, specificity, accuracy, and interobserver agreement for all four radiologists. More specifically, two of the four radiologists achieved a significant improvement in sensitivity (P=.03, P=.03), and all four radiologists achieved a significant improvement in accuracy (P = .01, P = .05, P = .009, P < .001). CONCLUSION: Current study results suggest that the addition of quantitative 1H MR spectroscopy to the breast MR imaging examination may help to improve the radiologist's ability to distinguish benign from malignant breast lesions.

Adolescent↗