Israel Medical Association Journal

Background: Neonatal cerebral imaging is a sensitive technique for evaluating brain injury in the neonatal period. When performing computed tomography or magnetic resonance imaging, sedation is needed to prevent motion artifacts. However, general anesthesia in neonates carries significant risks and requires a complex logistic approach that often limits the use of these modalities. The development of infant immobilizers now enables imaging without general anesthesia and significantly increases clinical and research investigational opportunities.

Objectives: To assess the efficacy of the infant immobilizer instead of general anesthesia for infants undergoing imaging.

Methods: The study group comprised all infants born over a 1 year period at Soroka University Medical Center who required imaging such as MRI, CT or bone scans. A MedVac Vacuum Splint infant immobilizer was used in all infants to prevent motion during imaging. The success rate of a single scan and the need for general anesthesia were assessed.  

Results: Forty infants were examined during 1 year. The studies included 15 CT scans, 25 MRIs and 1 bone scan. The infants’ gestational age at birth was 27–40 weeks and the examinations were performed at ages ranging from delivery to 6 months old. All imaging was successful and none of the infants required general anesthesia.

Conclusions: An infant immobilizer should be used for imaging of newborns. Since this method carries a low risk and has a high success rate, general anesthesia in newborns is justified only when this non-invasive procedure fails.
 

Background: An outbreak of respiratory illness caused by a novel swine-origin influenza virus (influenza A/H1N1 2009) that began in Mexico was declared a global pandemic by the World Health Organization in June 2009. The pandemic affected many countries, including Israel.

Objectives: To compare the course of chest radiographic and computed tomography findings in patients who survived and those who died following admission to the intensive care unit (ICU) or intubation due to severe laboratory-confirmed swine-origin influenza A/H1N1 2009.

Methods: We retrospectively reviewed the patient records (267 radiographs, 8 CTs) of 22 patients (10 males, 12 females) aged 3.5–66 years (median 34) with confirmed influenza A/H1N1 2009, admitted to the ICU and/or intubated in five major Israeli medical centers during the period July–November 2009. We recorded demographic, clinical, and imaging findings –including pattern of opacification, extent, laterality, distribution, zone of findings, and presence/absence of nodular opacities– at initial radiography and during the course of disease, and compared the findings of survivors and non-survivors. Statistical significance was calculated using the Wilcoxon (continuous variables) and Fisher's exact tests (categorical variables).

Results: The most common findings on the initial chest radiography were airspace opacities, which were multifocal in 17patients (77%) and bilateral in 16 (73%), in the lower or lower and middle lung zones in 19 patients (86%). Large airspace nodules with indistinct margins were seen in 8 patients (36%). Twelve patients survived, 10 died. Patients who died had multiple background illnesses and were significantly older than survivors (P = 0.006). Radiologic findings for the two groups were not significantly different.

Conclusion: Airspace opacities, often with nodular appearance, were the most common findings among patients with severeinfluenza A/H1N1 2009. The course of radiologic findings was similar in patients with severe influenza A/H1N1 2009 whosurvived and those who died.

Background: Many patients present to the emergency department with chest pain. While in most of them chest pain represents a benign complaint, in some patients it underlies a life-threatening illness.

Objectives: To assess the routine evaluation of patients presenting to the ED[1] with acute chest pain via the utilization of a cardiologist-based chest pain unit using different non-invasive imaging modalities.

Methods: We evaluated the records of 1055 consecutive patients who presented to the ED with complaints of chest pain and were admitted to the CPU[2]. After an observation period and according to the decision of the attending cardiologist, patients underwent myocardial perfusion scintigraphy, multidetector computed tomography, or stress echocardiography.

Results: The CPU attending cardiologist did not prescribe non-invasive evaluation for 108 of the 1055 patients, who were either admitted (58 patients) or discharged (50 patients) after an observation period. Of those remaining, 445 patients underwent MDCT[3], 444 MPS[4], and 58 stress echocardiography. Altogether, 907 patients (86%) were discharged from the CPU. During an average period of 236 ± 223 days, 25 patients (3.1%) were readmitted due to chest pain of suspected cardiac origin, and only 8 patients (0.9%) suffered a major adverse cardiovascular event.

Conclusions: Utilization of the CPU enabled a rapid and thorough evaluation of the patients’ primary complaint, thereby reducing hospitalization costs and occupancy on the one hand and avoiding misdiagnosis in discharged patients on the other.
 

[1] ED = emergency department

[2] CPU = chest pain unit

[3] MDCT = multidetector computed tomography

[4] MPS = myocardial perfusion scintigraphy

Background: Injury to patent grafts or cardiac chambers may occur during reoperation after coronary artery bypass grafting. Preoperative spatial localization of bypass grafts with computed tomography may improve the safety of these procedures.

Objectives: To characterize patients who undergo CT before repeat operations after previous coronary artery bypass grafting, and evaluate its benefit in terms of surgical outcome.

Methods: We compared 28 patients who underwent cardiac gated CT angiography before reoperation (CT group) to 45 re-do patients who were not evaluated with CT (no‑CT group).

Results: The two groups were similar in most preoperative and operative characteristics. The CT group, however, included more patients with patent saphenous vein grafts and fewer with emergency operations, acute myocardial infarction and need for intraaortic balloon pump support. During mid-sternotomy, there was no injury to grafts in the CT group, while there were two patent grafts and three right ventricular injuries in the no-CT group. There was no significant difference in perioperative mortality (3.6% vs. 8.9%). The overall complication rate in the CT group was 21.4% compared to 42.2% in the no‑CT group (P = 0.07). The only independent predictors of postoperative complications were diabetes mellitus, preoperative stroke and preoperative acute MI[1].

Conclusions: The patency and proximity of patent grafts to the sternum are well demonstrated by multidetector CT and may provide the surgeon with an important roadmap to avoid potential graft injury. A statistical trend towards reduced complications rate was demonstrated among patients who underwent CT angiography before their repeat cardiac operation. Larger series are required to demonstrate a statistically validated complication-free survival benefit of preoperative CT before repeat cardiac surgery.

Background: Magnetic resonance imaging of the breast has emerged as a valuable imaging tool in addition to conventional imaging modalities. It has high sensitivity for malignant lesions, and can detect mammographically, sonographically and clinically occult cancers. “MR only” lesions are best biopsied under MR guidance; however, this may be a challenging task.

Objectives:  To evaluate our initial clinical experience with MR-guided core needle breast biopsy and MR-guided needle localization.

Methods: We retrospectively evaluated 81 women with 97 lesions, who were scheduled for guided core needle biopsy or MR-guided needle localization followed by surgery. Lesions were categorized as malignant, high risk, or benign according to the BI- RADS MR classification system. MR findings were compared with final histopathology or with follow-up imaging findings.

Results: Fifteen (16%) lesions were malignant (9 invasive ductal carcinoma, 2 invasive lobular carcinoma, 4 ductal carcinoma in situ); 7 (7%) lesions were high risk (4 atypical ductal hyperplasia, 3 radial scars); 75 (77%) lesions were benign, mainly fibrocystic changes. Other benign findings were sclerosing adenosis, pseudoangiomatous stromal hyperplasia, fat necrosis, intraductal papilloma, fibroadenoma, capillary hemangioma, and florid ductal hyperplasia. No major complications were encountered.
Conclusions: MR-guided interventional procedures of the breast are accurate, safe and feasible methods for sampling breast lesions detected only by MR and have become a significant tool in the management of certain patients.

Background: Stem cell-based therapy is a promising approach for the treatment of neurodegenerative disease. In our laboratory, a novel protocol has been developed to induce bone marrow-derived mesenchymal stem cells into neurotrophic factor-secreting cells. These cells produce and secrete factors such as BDNF (brain-derived neurotrophic factor) and GDNF (glial-derived neurotrophic factor).

Objectives: To evaluate the migratory capacity and efficacy of NTF-SC[1] in animal models of Parkinson's disease and Huntington's disease.

Methods: MSCs[2] underwent two-phase medium-based induction. An efficacy study was conducted on the 6-hydroxydopamine-induced lesion, a rat model for Parkinson's disease. Cells were transplanted on the day of 6-OHDA[3] administration, and amphetamine-induced rotations were measured as a primary behavioral index. In a second experiment, migratory behavior was examined by transplanting cells a distance from a quinolinic acid-induced striatal lesion, a rat model for Huntington's disease. Migration, in vivo, was monitored using longitudinal magnetic resonance imaging scans followed by histology.

Results: NTF-SCs attenuated amphetamine-induced rotations by 45%. HPLC analysis demonstrated a marked decrease in dopamine depletion, post-cellular treatment. Moreover, histological assessments revealed that the engrafted cells migrated and acted to regenerate the damaged striatal dopaminergic nerve terminal network. In a preliminary work on an animal model for Huntington's disease, we demonstrated by high resolution MR images and correlating histology that induced cells migrated along the internal capsule towards the QA[4]-induced lesion.

Conclusions: The induced MSCs are a potential therapy for neurodegenerative diseases, due both to their NTF secretion and their ability to migrate towards the diseased tissue.

Background: Aural cholesteatoma is an epidermal cyst of the middle ear or mastoid that can only be eradicated by surgical resection. It is usually managed with radical or modified radical mastoidectomy. Clinical diagnosis of recurrent cholesteatoma in a closed postoperative cavity is difficult. Thus, the accepted protocol in most otologic centers for suspected recurrence consists of second-look procedures performed approximately 1 year after the initial surgery. Brain herniation into a post-mastoidectomy cavity is not rare and can be radiologically confused with cholesteatoma on the high resolution computed tomographic images of temporal bones that are carried out before second-look surgery.

Objectives: To present our experience with meningoceles that were confused with recurrent disease in patients who had undergone primary mastoidectomy for cholesteatoma and to support the use of magnetic resonance imaging as more suitable than CT in postoperative follow-up protocols for cholesteatoma.

Methods: We conducted a retrospective chart review of four patients.

Results: Axial CT sections demonstrated a soft tissue mass in the middle ear and mastoid in all four patients. Coronal reconstructions of CT scans showed a tympanic tegmen defect in two patients. CT failed to exclude cholesteatoma in any patient. Each underwent a second-look mastoidectomy and the only finding at surgery was meningocele in all four patients.

Conclusions: Echo-planar diffusion-weighted MRI can differentiate between brain tissue and cholesteatoma more accurately than CT. We recommend that otolaryngologists avoid unnecessary revision procedures by using the newest imaging modalities for more precise diagnosis of the patients who had undergone mastoidectomy for cholesteatoma in the past.
 

Background: Manganism is a central nervous system disorder caused by toxic exposure to manganese. Manganism has been related to occupational exposures, liver diseases, prolonged parenteral nutrition, and abuse of illicit drugs. Initially manifested by a reversible neuropsychiatric syndrome (locura manganica), the main symptoms and signs of manganism are emotional lability, compulsive behavior and visual hallucinations. Locura manganica is followed by an irreversible extrapyramidal syndrome, the onset of which occurs years after chronic exposure.

Objectives: To characterize the regional distribution of Mn[1] in the rat brain after subchronic exposure to Mn. This animal model holds special clinical relevance, reflecting the earlier clinical stages of manganism before chronic exposure to Mn exerts its irreversible effects.

Methods: Sprague-Dawley rats were intravenously injected with MnCl₂ weekly, for a total of 14 weeks – approximately 1/10 of the lifetime of the rat. T1-weighted magnetic resonance imaging was used to detect the distribution of Mn deposition in brain tissues, as evidenced by areas of T1-weighted hyperintense signals.

Results: A consistent region-specific pattern of T1-weighted hyperintensities was observed in the brains of Mn-treated rats. Cortical hyperintensities were prominent in the hippocampus and dentate gyrus. Hyperintensities were also observed in the olfactory bulbs, pituitary gland, optic nerves and chiasma, pons, midbrain tegmentum, habenula, lentiform and caudate nuclei, thalamus, chorioid plexus and cerebellar hemispheres.

Conclusions: Prominent Mn depositions, evidenced by T1-weighted hyperintensities in the hippocampus after subacute exposure to Mn, are compatible with the clinical picture of manganism during its early stages; and may explain its pathophysiology.