Glenn Tung

John Brown University · Diagnostic Imaging

ACL injuries place the knee at risk for post‐traumatic osteoarthritis (PTOA) despite surgical ACL reconstruction (ACLR). One parameter thought to affect PTOA risk is the initial graft tension. This randomized controlled trial (RCT) was designed to compare outcomes between two graft tensioning protocols that bracket the range commonly used. At 7‐yea...

Neuroimaging manifestations of COVID-19 are being reported with increasing frequency with recent reports of associated atypical leukoencephalopathies. We add to this literature by describing a COVID-19 + patient who demonstrated imaging findings typical for posterior reversible encephalopathy syndrome (PRES). The inflammatory syndrome associated wi...

Purpose Patients with large vessel occlusion and target mismatch on imaging may be thrombectomy candidates in the extended time window. However, the ability of imaging modalities including non-contrast CT Alberta Stroke Program Early Computed Tomographic Scoring (CT ASPECTS), CT angiography collateral score (CTA-CS), diffusion-weighted MRI ASPECTS...

We describe the case of a patient with anti-Hu paraneoplastic limbic encephalitis secondary to small cell lung cancer in whom imaging demonstrated migratory luid-attenuated inversion recovery (FLAIR) hyperintensities in the frontal, temporal and occipital lobes which resolved with minimal residual gliosis after immunotherapy. Paraneoplastic limbic...

Background and purpose: Within the thrombolysis in cerebral infarction (TICI) classification, TICI 2b has been historically considered successful recanalization. Recent studies have suggested that TICI 3 and a proposed TICI 2c should be separately reported from TICI 2b, in both the original (>66% reperfusion) and modified (>50% reperfusion) defini...

Introduction: Since mechanical thrombectomy was established as the gold standard for treatment of stroke caused by an emergent large vessel occlusion (ELVO), comprehensive stroke centers have worked to streamline their workflow and minimize time-to-intervention; the ability to rapidly review CT angiography (CTA) is one hurdle in that process. To th...

Background and purpose: The Thrombolysis in Cerebral Infarction (TICI) 2b classification is defined as “near complete” recanalization for acute ischemic stroke. While this category has historically combined with TICI 3 (“complete reperfusion”) as “successful recanalization”, recent studies have suggested that TICI 3 and a proposed intermediate TICI...

Background and purpose: We compared the value of Alberta Stroke Program Early Computed Tomographic scoring using CT (CT ASPECTS), collateral score on CT angiography (CTA), ASPECTS using diffusion-weighted MRI (DWI ASPECTS), DWI lesion volume, and DWI volume with National Institute of Health Stroke Scale (NIHSS) in determining candidacy of patients...

Background: The "initial graft tension" applied at the time of graft fixation during anterior cruciate ligament (ACL) reconstruction surgery modulates joint contact mechanics, which in turn may promote posttraumatic osteoarthritis (OA). Purpose/hypotheses: The study objectives were to compare clinical, functional, patient-reported, and OA imagin...

We present a case of caudal regression syndrome (CRS), a relatively uncommon defect of the lower spine accompanied by a wide range of developmental abnormalities. CRS is closely associated with pregestational diabetes and is nearly 200 times more prevalent in infants of diabetic mothers (1, 2). We report a case of prenatally suspected CRS in a fetu...

Clinical, functional, and patient-oriented outcomes are commonly used to evaluate the efficacy of treatments after anterior cruciate ligament (ACL) injury; however, these evaluation techniques do not directly measure the biomechanical changes that occur with healing. To determine if the magnetic resonance (MR) image-derived parameters of graft volu...

PURPOSE/AIM TDI is common but frequently overlooked or incorrectly described by radiologists. In a busy level I trauma center, a dental consultation for TDI occurs daily. This electronic exhibit will raise awareness of dental trauma by reviewing basic dental anatomy, discussing the spectrum of TDI and focusing on radiologic findings that most impac...

Background: The initial graft tension applied at the time of anterior cruciate ligament (ACL) reconstruction alters joint contact and may influence cartilage health. The objective was to compare outcomes between 2 commonly used "laxity-based" initial graft tension protocols. Hypotheses: (1) The high-tension group would have less knee laxity, imp...

A previously healthy 40-year-old male called paramedics after experiencing palpitations, weakness, and presyncope. In the emergency room, the 12-lead ECG shown in Fig. 168.1 was recorded. What rhythm is shown on the ECG? What is the best approach for acute therapy?

Quantifying changes in meniscal volume in vivo before and after partial meniscectomy (PM) could help elucidate the mechanisms involved in osteoarthritis development after meniscal injury and its surgical treatment. Purpose/ To determine whether quantitative magnetic resonance imaging (qMRI) can detect the immediate reduction in meniscal volume crea...

The objective of our study was to determine the relationship between the apparent diffusion coefficient (ADC) value on diffusion-weighted imaging (DWI) and Gleason score of prostate cancer and percentage of tumor involvement on prostate core biopsy. We performed a retrospective study of 57 patients with biopsy-proven prostate cancer who underwent e...

A 31-year-old woman with morning glory optic disc anomaly (MGDA) developed acute retrobulbar optic neuritis and a bullous macular detachment. MRI demonstrated truncation of the perineural space of the affected optic nerve as well as focal optic nerve enhancement. Optical coherence tomography (OCT) showed retinoschisis associated with the macular de...

Early detection of glycosaminoglycan (GAG) loss may provide insight into mechanisms of cartilage damage in the anterior cruciate ligament (ACL)-injured patient. We hypothesized that tibial and femoral Delayed Gadolinium-Enhanced MR Imaging of Cartilage (dGEMRIC) indices would be lower in the medial compartment of the ACL-injured knee than in the co...

Osteoarthritis and avascular necrosis are common clinical entities with unknown origins. Recently, vascular changes were implicated in the pathogenesis of both conditions. This article discusses the use of novel noninvasive imaging techniques as a means of assessing bone perfusion and quantifying differences seen in osteoarthritis and avascular nec...

Objective: The purpose of this article is to review mechanisms of injury leading to posterior glenohumeral instability and the correlated imaging findings on CT and MRI. Conclusion: In patients with suspected posterior glenohumeral instability, imaging of the affected shoulder can show abnormalities of the bone, labrum, and joint capsule. Accura...

PURPOSE To determine if diffusion weighted imaging (DWI) improves interreader agreement for both prostate cancer identification and staging of extracapsular extension (ECE) and seminal vesicle invasion (SVI). METHOD AND MATERIALS We performed an IRB approved retrospective review of endorectal prostate MRI performed with T2-weighted imaging and DWI...

PURPOSE Although there are imaging signs of advanced discitis, osteomyelitis, and spinal epidural abscess (SEA), signs of early infectious spondylitis are less well known. The purpose of this study is to describe imaging signs of early infectious spondylitis that were unrecognized on imaging tests performed prior to diagnostic spinal MR imaging. M...

A study was conducted to demonstrate the size and concentration effect of gold nanoparticles (GNPs) on X-ray attenuation measured by computed tomography (CT). The GNPs were prepared by borohydride reduction of gold salts in the presence of sodium citrate. The X-ray attenuation of GNPs at different concentrations was compared with a commercial iodin...

To assess the effects of interference screws, which are commonly used to surgically fix an anterior cruciate ligament (ACL) graft in the ACL-deficient knee, and magnetic field strength on cartilage volume and thickness measurements with quantitative magnetic resonance imaging (qMRI). Five cadaver knees were imaged using a cartilage-sensitive sequen...

To assess the reliability and accuracy of manual and semi-automated segmentation methods for quantifying knee cartilage thickness. This study employed both manual and LiveWire-based semi-automated segmentation methods, ex vivo and in vivo, to measure tibiofemoral (TF) cartilage thickness. The articular cartilage of a cadaver knee and a healthy volu...

Tension pneumocephalus is an unusual, potentially life-threatening complication of frontal fossa tumors. We present an uncommon case of a frontoethmoidal osteoma causing a tension pneumocephalus and neurological deterioration prompting a combined endonasal ethmoidectomy and bifrontal craniotomy with craniofacial approach for resection. A 68-year-ol...

Meniscal injuries place the knee at risk for early osteoarthritis (OA) because they disrupt their load-bearing capabilities. Partial resection is routinely performed to alleviate symptomatic meniscal tears. While the removal of meniscal tissue may not be the only factor associated with partial meniscectomy outcome, the amount removed certainly cont...

Bone marrow edema is seen in osteoarthritis, avascular necrosis, and other clinical conditions including the bone marrow edema syndrome. Bone marrow edema is associated with bone pain and may be related to the pathophysiology of osteoarthritis. Our hypothesis is that bone marrow edema is associated with a reduction in perfusion in subchondral bone,...

PURPOSE Bone marrow edema (BME)can be associated with osteoarthritis (OA), avascular necrosis (AVN), and other causes. Its pathophysiology remains largely unknown. In this study, we compare perfusion kinetics of normal marrow and BME using dynamic, contrast-enhanced (DCE)-MRI. METHOD AND MATERIALS DCE-MR imaging of the knee (n=15), hip (n=8), or a...

PURPOSE/AIM The purpose of this educational exhibit is to review mechanisms of shoulder injury leading to posterior glenohumeral instability (PGHI) and to present characteristic imaging findings on CT, MR imaging and MR arthrography of osseous and soft tissue lesions associated with PGHI. CONTENT ORGANIZATION PGHI presents with shoulder pain, and...

Objective: The purpose of this pictorial essay is to discuss the differential diagnosis of cerebral microhemorrhages on T2*-weighted gradient-echo MRI. Conclusion: Cerebral amyloid angiopathy and chronic systemic hypertension are the two most common causes of cerebral microhemorrhages. Less common causes include diffuse axonal injury, cerebral e...

Continuous voice recognition dictation systems for radiology reporting provide a viable alternative to conventional transcription services with the promise of shorter report turnaround times and increased cost savings. While these benefits may be realized in academic institutions, it is unclear how voice recognition dictation impacts the private pr...

Objective: The purpose of this article is to highlight the normal anatomic features of the meniscal roots on photographs of dissected cadaveric knee specimens and 3-T MR images. Conclusion: The meniscal roots, which are critical attachment sites of the medial and lateral menisci to the central tibial plateau, are well-visualized on intermediate-...

A 39-year-old man, who presented at age 312 with Landau-Kleffner syndrome, had persisting oral and written language deficits into adulthood. Seizures were easily controlled in childhood, but reemerged in adulthood as medication-refractory complex partial seizures. Abnormal T2 signal hyperintensity was seen in the left mesial temporal area on brain...

PURPOSE Bone Marrow Edema (BME) has been associated with many diseases including osteoathritis and osteonecrosis; however, the pathophysiology of BME is not known. In this study, we investigate perfusion kinetics of BME with dynamic contrast enhanced MRI (DCE-MRI). METHOD AND MATERIALS MR imaging was performed on 16 adults with BME using a 1.5T ma...

Mixed-density convexity subdural hematoma and interhemispheric subdural hematoma suggest nonaccidental head injury. The purpose of this retrospective observational study is to investigate subdural hematoma on noncontrast computed tomography in infants with nonaccidental head injury and to compare these findings in infants with accidental head traum...

To retrospectively determine the prevalence of posterior lateral meniscus root tears (LMRTs), as depicted on magnetic resonance (MR) images, in patients with an anterior cruciate ligament (ACL) tear and to investigate the association of LMRTs with lateral meniscus extrusion and other ligament injuries. Institutional review board approval was obtain...

We describe a method to accurately assess articular cartilage morphology using the three-dimensional laser scanning technology. Traditional methods to obtain ground truth for validating the assessment of cartilage morphology from MR images have relied on water displacement, anatomical sections obtained with a high precision band saw, stereophotogra...

The purpose of this study was to determine the prevalence of hydrocephalus in patients with vestibular schwannoma. A second objective was to investigate possible etiologies for hydrocephalus in this population by attempting to correlate the incidence and severity of hydrocephalus with tumor volume and extent of fourth ventricular compression. The M...

This was a retrospective study of 101 consecutive patients (104 shoulders) with chronic, atraumatic shoulder pain who were evaluated by a fellowship-trained shoulder specialist. The patients were assessed with a complete history, physical examination, plain radiographs, Simple Shoulder Test, and visual analog scores of pain, shoulder function, and...

To compare conspicuity of liver hemangiomas on STIR, T1-weighted, and T2-weighted magnetic resonance (MR) images before and after administration of gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA) (hepatocellular contrast agent), using contrast-to-noise ratios (CNRs). Thirteen hemangiomas were imaged using breath-hold gradie...

PURPOSE Early reports suggested that 1H-MRSI might serve as a useful lateralizing test in pre-surgical evaluation of patients. However, later reports have refuted that impression. This study prospectively examines the predictive value of 1H-MRSI in patients with intractable TLE. METHOD AND MATERIALS Consecutive patients with intractable TLE (n=14)...

PURPOSE Medial meniscus root tears (MMRT) may be a risk factor for premature osteoarthritis due to abnormal biomechanics that result from meniscal extrusion. Recently, lateral meniscus root tears (LMRT) associated with ACL disruptions have also been reported. The objective of this study was to evaluate the prevalence of meniscus root tears and meni...

To prospectively compare the effectiveness of multi-detector row computed tomographic (CT) angiography with that of conventional intraarterial digital subtraction angiography (DSA) used to detect intracranial aneurysms in patients with nontraumatic acute subarachnoid hemorrhage. Thirty-five consecutive adult patients with acute subarachnoid hemorrh...

Objective: This retrospective study reports the diffusion-weighted MRI appearance of Toxoplasma abscesses, rim-enhancing cerebral masses resulting from toxoplasmosis infection. In all patients, the signal intensity of the abscess core on diffusion-weighted MRI was equal to or less than that of normal, unaffected cerebral white matter and the measu...

Restricted water diffusion has been used to distinguish pyogenic abscess from other rim-enhancing brain masses; however diffusion-weighted imaging of cerebral infection before capsule formation has rarely been described. We report a case of fungal cerebritis in which water diffusion was more restricted than that of normal contralateral brain and th...

We evaluated a method for quantifying vasogenic edema (VE) on MRI to identify brain hematomas caused by neoplasms. We performed a blinded review of 68 acute and subacute hematomas caused by neoplasms (22), hypertension or presumed amyloid angiopathy (27), or vascular malformations (19). The extent of vasogenic edema was quantified on an axial T2-we...

Restricted water diffusion has been used to distinguish pyogenic abscess from other rim-enhancing brain masses; however diffusion-weighted imaging of cerebral infection before capsule formation has rarely been described. We report a case of fungal cerebritis in which water diffusion was more restricted than that of normal contralateral brain and th...

To present a case of a primary orbital leiomyosarcoma and the corresponding magnetic resonance imaging (MRI) appearance. Observational case report. Correlation of MRI with clinicopathologic findings. A 56-year-old woman presented with a 10-month history of diplopia in left gaze and left exophthalmos. An enhanced MRI of the left orbit revealed an ex...

The purpose of our study was to investigate the relationship between tears of the posterior labrocapsular complex and glenohumeral alignment on MR arthrography and the presence and extent of posterior labrocapsular tears in patients with posterior instability. Posterior labrocapsular tears identified on 24 MR arthrograms and surgically confirmed we...

Objective: The purpose of this study was to describe the features of pyogenic ventriculitis (ventricular empyema, pyocephalus) on diffusion-weighted MR imaging. Conclusion: Markedly increased signal intensity of dependent intraventricular fluid on diffusion-weighted MR imaging and an apparent diffusion coefficient that is less than that of norma...

Pituitary apoplexy is defined as a clinical syndrome that may include headache, visual deficits, ophthalmoplegia, or altered mental status. It may result from either infarction or hemorrhage of the pituitary gland. Prognosis is significantly improved with early diagnosis and surgical treatment. We report two cases in which diffusion-weighted MR ima...

The purpose of this study was to evaluate the response of pituitary adenomas to radiosurgery as manifested by changes in size and appearance on serial MR imaging. Over a mean follow-up period of 36 months, changes in 44 pituitary adenomas were assessed on 147 enhanced MR imaging studies. Prior surgery had been performed in 36 tumors (82%). At the t...

OBJECTIVE: This retrospective study investigated the specificity of restricted water diffusion for the diagnosis of brain abscess. Two of five rim-enhancing brain masses with restricted water diffusion (apparent diffusion coefficient of 0.79 [10(-3) mm(2)/sec] or less) were brain abscesses, but diagnoses in the other cases were metastatic squamous...

OBJECTIVE. This retrospective study investigated the specificity of restricted water diffusion for the diagnosis of brain abscess. Two of five rim-enhancing brain masses with restricted water diffusion (apparent diffusion coefficient of 0.79 [10-3 mm2/sec] or less) were brain abscesses, but diagnoses in the other cases were metastatic squamous cell...

The purpose of this work was to investigate signs of subscapularis tendon tear on MRI. Preoperative written interpretations of high field (n = 9) and low field (n = 7) MRI of 16 patients with tears confirmed at surgery or arthroscopy were reviewed, followed by retrospective review of these studies. A preoperative diagnosis of subscapularis tear was...

A 7-year-old girl with primary varicella presented with encephalopathy and focal neurologic deficits 10 days after her first skin lesions appeared. She was discovered to have bilateral wedge-shaped renal infarctions, and ischemic lesions in the conus medullaris, cerebral cortex, and deep gray matter consistent with a medium and large vessel arterit...

Epstein-Barr virus encephalitis is a self-limiting disease with few sequelae. Persistence of neurologic deficits prior to and after the acute illness has yet to be described in children. We describe five children with persistent cognitive and focal neurologic deficits due to chronic Epstein-Barr virus encephalitis with various T2-weighted magnetic...

We investigated the pathophysiology of paraglenoid labral cysts on the basis of MR imaging, MR arthrography, and cyst aspiration. From 2211 MR imaging examinations, 51 (2.3%) cysts in 46 patients were identified. MR arthrography (n = 5), cystography (n = 1), arthroscopy (n = 17), percutaneous needle aspiration (n = 4), and medical records were also...

The patient is a 19-year-old man with a 10-month history of nasal congestion and worsening epistaxis for the past 3 months. Previous medical history is significant for bilateral retinoblastoma at age 3 that was treated with left eye enucleation and ocular implant, and conventional radiation treatment of the right globe. Computed tomography (CT), en...

The purpose of this study was to determine the performance characteristics of high-field and low-field MR imaging for the diagnosis of a glenoid superior labral anteroposterior (SLAP) tear. High-field (n = 46) or low-field (n = 21) MR imaging was performed on 41 patients with SLAP tears and 26 patients with normal superior labra. The superior labru...

Our purpose was to determine if specific MRI findings in spinal epidural abscess (SEA), at the time of diagnosis, are associated with the clinical outcome. The clinical records and MRI studies of 18 patients with SEA were reviewed and follow-up was obtained from the outpatient medical record, telephone interview, or both. The association between fi...

The purpose of this study was to determine whether an in-hospital transportable CT scanner can provide diagnostic brain images and to compare the quality of these images with those from a conventional fixed-platform CT scanner. Twenty-seven patients with known or suspected intracranial pathology underwent imaging on a transportable scanner and a fi...

Our goal was to assess the value of MR imaging to patient care in the setting of angiographically negative subarachnoid hemorrhage and to evaluate the potential of MR imaging for revealing the mechanism for idiopathic perimesencephalic subarachnoid hemorrhage. We retrospectively reviewed 71 patients who presented with subarachnoid hemorrhage and in...

This retrospective study compared the magnetic resonance imaging (MRI) findings in 87 patients with acute and chronic anterior cruciate ligament (ACL) tears. Sixty patients had acute tears and 27 had chronic tears. The appearance of the torn ligament was examined on MRI, and associated meniscal and osteochondral injuries were described. All finding...

In this study, 12 patients over age 60 with depression with moderate to severe subcortical hyperintensities (SH) localized to the periventricular white matter were identified by quantitative MRI. Using the California Verbal Learning Test, they were compared with 12 age-, education-, and severity-matched patients with depression with minimal white m...

We investigated the correlation between cortical perfusion and white matter hyperintensities on magnetic resonance images (MRI) of patients with dementia. The study included 40 subjects, each of whom had undergone both MRI and single-photon emission computed tomography (SPECT) studies as part of their diagnostic evaluation for degenerative dementia...

The team physician is faced with an array of imaging studies to evaluate the injured athlete, including CT scans, conventional and cross-sectional arthrography, bone scanning, sonography, and MR imaging. An understanding of the clinical usefulness of these examinations requires some knowledge of the physical principles on which they are based. This...

Meniscal and nonosseous anterior cruciate ligament (ACL) injuries are being recognized in children and adolescents more frequently. This increase appears to be the result of better diagnostic skills, newer imaging techniques, and the ever-increasing physical demands of organized youth sports. We retrospectively reviewed all cases of knee arthroscop...

We sought to determine whether geriatric patients with late-life-onset major depression have more subcortical hyperintensities on MRI and greater cognitive impairment than age-matched geriatric patients with early-life-onset major depression, suggesting that subcortical disease may be etiologic in late-life depression. Most negative studies of the...

Data from 30 elderly inpatients with major depression were analyzed to explore the relationship between subcortical hyperintensities (SH) on MRI and activities of daily living (ADLs). A comparison of subjects based on a median split of the severity of SH revealed that subjects with greater SH performed worse on both instrumental and physical ADLs....

MR imaging is used to characterize cavernous hemangiomas of the liver because these neoplasms have a long transverse relaxation time compared with normal liver parenchyma and other hepatic neoplasms. The purpose of this study was to correlate the pathologic findings of hemangiomas with their appearance on high-field MR images and with mean T2 relax...

A Tc-99m bone scan of a patient with classic roentgenographic findings of osteopoikilosis revealed multiple foci of increased activity that corresponded to many of the sclerotic foci on the roentgenograms. The authors presume that the abnormal bone scan in this patient reflects active osseous remodeling, similar to what has been observed in bone is...

A Tc-99m bone scan of a patient with classic roentgenographic findings of osteopoikilosis revealed multiple foci of increased activity that corresponded to many of the sclerotic foci on the roentgenograms. The authors presume that the abnormal bone scan in this patient reflects active osseous remodeling, similar to what has been observed in bone is...

To investigate primary and secondary signs of anterior cruciate ligament (ACL) tear at magnetic resonance (MR) imaging, the authors retrospectively reviewed 103 MR imaging examinations obtained in 99 patients, the original interpretations of these examinations, clinical records, and arthroscopy reports. Fifty cases of arthroscopy-documented complet...

In a retrospective review of percutaneous needle biopsy in 38 patients, we assessed the safety of this procedure for establishing the diagnosis of cavernous hemangioma of the liver. Computed tomography (CT) or ultrasound was used to direct the biopsy of focal liver lesions ranging in size from 1 to 13.5 cm, with a median size of 3 cm. In all patien...

Magnetic resonance imaging is used widely to investigate soft tissue masses. The effectiveness of MRI derives from unrivaled soft tissue contrast and multiplanar imaging capability. Magnetic resonance spectroscopy has been used to examine the phosphometabolites of normal and pathological soft tissues. We review the role of MRI and MRS in the detect...

The incidental adrenal mass is encountered with greater frequency than in the past because of the increasing use of cross-sectional imaging in clinical practice. The evaluation and treatment of an adrenal mass depends on clinical history, endocrinological assessment, and whether the mass is detected incidentally or after a directed search for adren...

Three patients with pyocystis and urethral obstruction were successfully treated with percutaneous placement of a suprapubic cystostomy catheter. This approach is an alternative to transurethral bladder irrigation or cystectomy in selected patients.

A large Gartner duct cyst associated with solitary crossed renal ectopia was diagnosed in a young woman presenting with dyspareunia and pelvic pain. Among the radiologic imaging modalities used, magnetic resonance imaging and sonography were the most helpful in determining the cystic nature of the mass, its separation from other pelvic organs, as w...