Mery Kato

Typical and Atypical Perfusion Patterns in Periictal SPECT of Patients with Unilateral Temporal Lobe Epilepsy

Summary:  Purpose: To characterize perfusion patterns of periictal single‐photon emission tomography (SPECT) in patients with unilateral temporal lobe epilepsy (TLE) and to determine their relationship to the epileptogenic zone (EZ).

Pontine activation during focal status epilepticus secondary to hamartoma of the floor of the fourth ventricle

Epileptic seizures associated with hamartoma of the floor of the fourth ventricle (HFFV) are generally resistant to antiepileptic medication, may evolve into status epilepticus, and can respond favorably to surgical therapy. HFFV are rare, and during the neonatal or infantile period may be associated with repetitive and stereotyped attacks of hemifacial spasm, eye blinking, facial movements, head deviation and dysautonomic manifestations. Similarly, to gelastic seizures provoked by hypothalamic hamartomas, it has been suggested that these spells arise from within the HFFV, thus constituting a type of non-cortical seizure. We report an infant female patient that developed continuous left hemifacial attacks since she was 2-month-old, and that underwent presurgical investigation when she was 18-month-old. MRI disclosed a left sided HFFV, Video-EEG showed non-localizing and non-lateralizing findings, and SPECT aligned with MRI showed marked hyperperfusion within the hamartoma, spreading to ipsilateral cerebellar parenchyma and brainstem nuclei. Patient underwent lesionectomy and became seizure-free. We found two evidences on literature supporting the hypothesis of non-cortical seizures related to HFFV. The first, intra-cerebellar recordings surrounding hamartoma showed electrical activity related to seizures. The second, subtracted SPECT co-registered MRI showed hyperemia within hamartoma. The present report provides the third additional evidence. We found the involvement not only of the hamartoma, and pars of cerebellar hemisphere, but also an intense hyperemia involving brainstem nuclei during seizures. We believe that all these findings suggest a short subcortical network responsible for generating seizures in HFFV patients.

Ictal chronology and interictal spikes predict perfusion patterns in temporal lobe epilepsy: a multivariate study

Typical (TPP) and atypical (APP) perfusion patterns (PP) may be seen in ictal SPECT of patients with temporal lobe epilepsy (TLE). APP may pose problem in the lateralization of the epileptogenic zone (EZ). We aimed to investigate predictive variables for the occurrence of TPP and APP. Fifty-one TLE patients were submitted to successful anterior-mesial temporal lobectomy. Univariate (UVA) and multivariate (MVA) analysis were performed upon clinical data, distribution of interictal spikes, and ictal chronology of seizures. From MVA, a final predictive model (FPM) was determined to better predict TPP and APP. Forty patients showed TPP (78.5%) and 11 patients APP (21.5%). Accuracy of ictal SPECT was higher in the unilateral (UIS) than in the bilateral (BIS) interictal spikes group (P = 0.05). FPM showed that patients exhibiting BIS, with shorter proportion of the electrographic seizure occurring after completion of tracer injection, and longer clinical than EEG seizure duration had more APP (P = 0.003). Generalized tonic-clonic seizures did not result in more APP. We concluded that analysis of ictal SPECT in TLE requires the knowledge of TPP and APP, the distribution of interictal spikes on temporal lobes and the ictal chronology of seizures. BIS showed that beyond a more complex epileptogenicity and seizure propagation, they may also lead to APP.

Late evaluation of the relationship between morphological and functional renal changes and hypertension after non-operative treatment of high-grade renal injuries

ObjectiveTo evaluate the anatomical and functional renal alterations and the association with post-traumatic arterial hypertension.MethodsThe studied population included patients who sustained high grades renal injury (grades III to V) successfully non-operative management after staging by computed tomography over a 16-year period. Beyond the review of medical records, these patients were invited to the following protocol: clinical and laboratory evaluation, abdominal computed tomography, magnetic resonance angiography, DMSA renal scintigraphy, and ambulatory blood pressure monitoring. The hypertensive patients also were submitted to dynamic renal scintigraphy (99mTc EC), using captopril stimulation to verify renal vascular etiology.ResultsOf the 31 patients, there were thirteen grade III, sixteen grade IV (nine lacerations, and seven vascular lesions), and two grade V injuries. All the patients were asymptomatic and an average follow up post-injury of 6.4 years. None had abnormal BUN or seric creatinine. The percentage of renal volume reduction correlates with the severity as defined by OIS. There was no evidence of renal artery stenosis in Magnetic Resonance angiography (MRA). DMSA scanning demonstrated a decline in percentage of total renal function corresponding to injury severity (42.2 ± 5.5% for grade III, 35.3 ± 12.8% for grade IV, 13.5 ± 19.1 for grade V). Six patients (19.4%) had severe compromised function (< 30%). There was statistically significant difference in the decrease in renal function between parenchymal and vascular causes for grade IV injuries (p < 0.001). The 24-hour ambulatory blood pressure monitoring detected nine patients (29%) with post-traumatic hypertension. All the patients were male, mean 35.6 years, 77.8 % had a familial history of arterial hypertension, 66.7% had grade III renal injury, and average post-injury time was 7.8 years. Seven patients had negative captopril renography.ConclusionsLate results of renal function after conservative treatment of high grades renal injuries are favorable, except for patients with grades IV with vascular injuries and grade V renal injuries. Moreover, arterial hypertension does not correlate with the grade of renal injury or reduction of renal function.

Imaging in Kidney Transplantation

At the end-stage of renal failure, the best option for treatment is kidney transplantation, before starting any form of dialysis. The scarcity of organs from cadaveric donors and the comorbidity of the receptors patients, delay this treatment from being routinely performed prior to dialysis. Living-donor kidney transplantation can meet this objective perfectly, since it does not depend on waiting lists imposed by cadaveric donation [1]. In recent years, the expansion of genetically unrelated living donation has facilitated living-donor kidney transplantation as spouses, distant relatives, and even good friends have increased the pool of potential living donors. The living-donor transplants offer better survival than those of cadaveric-donor transplants, despite of HLA compatibility [2, 3].

Good response of low-fat/high-protein diet in a patient with chyluria

Abstract Chyluria is an inappropriate urinary excretion of chyle that turns the urine milky. A nutritional approach based on low-fat/high-protein content diet associated or not with medium-chain triglyceride (MCT) showed to be an efficient conservative treatment to improve the milky urine appearance in a patient with chyluria. Case report: A 30-year-old female patient was admitted with chyluria of unknown etiology. An ureteropyeloscopy revealed a single lesion in each kidney, both with linear aspect and measuring 5 mm in extension. These lesions were located close to the renal papillae and were leaking a cloudy and milky fluid. Both lesions were laser cauterized followed by improvement of the milky urine. However, the chyluria relapsed after few months and a low-fat/high-protein content diet with 10 g of soybean oil to meet the requirements essential fatty acids (EFA) and with MCT from coconut oil as alternative to prepare foods was started. Few weeks later the patient returned reporting consistent improvement of the milky urine appearance related with the use of the diet. However since the diet was tasteless and time consuming to prepare, she reported low compliance to diet with MCT and the milky urine relapsed. The MCT was discontinued and the diet with EFA source was maintained with better compliance. Since then the chyluria remains in remission. In conclusion, the dramatic improvement of the milky urine with low-fat/high-protein diet with EFA source observed in our patient demonstrates that this nutritional approach is efficient with fast results to treat chyluria during long term.

Epistaxis during a generalized seizure leading to an atypical ictal SPECT finding at the skull base

INTRODUCTION: Generalized tonic-clonic seizures (GTCS) are among the most dramatic types of epileptic seizures and may be accompanied by rising blood pressure and pulse rate, physical injuries from falling, muscular convulsions, tongue biting, or aspiration pneumonia. Epistaxis is an uncommon complication of generalized seizures and investigations should exclude local or systemic disorders. OBJECTIVE: We aim to report a 29-year-old male patient with medically intractable right temporal lobe epilepsy whose ictal SPECT showed a conspicuous high extracerebral accumulation of the tracer at the skull base. METHODS: The tracer 99mTc-ECD was injected during a GTCS complicated by simultaneous epistaxis during a long term video-electroencephalographic monitoring. RESULTS: Initially, SPECT images showed an unexpected hot spot at the skull base suggesting pharyngeal or pituitary tumors. Clinical history disclosed chronic sinusitis and rare episodes of epistaxis. White and red cells blood count, platelet count, serum biochemistry, coagulation tests, and rest arterial blood pressure were normal. Computed tomography and MRI excluded sinusoidal expansive or vascular lesions, head trauma, fractures or acute infections. Subtracted SPECT disclosed a focal high concentration of the radiotracer within the left sphenoid sinus, probably related to the nose bleeding. CONCLUSION: This is a singular case of a brain SPECT artifact secondary to a nasal bleeding during a generalized seizure that was misinterpreted as neoplastic disease. Also, this case raises concerns about the pathophysiological relationship among epileptic seizures, nasal bleedings and chronic sinusitis.

Characterization of resolution, sensitivity, and shielding of a gamma-probe for sentinel lymph node localization: an experimental study

Objective The aim of this study was to evaluate angular, spatial, and energy resolution, sensitivity, and shielding of a gamma-probe. Materials and methods The EUROPROBE II gamma-probe (EuroRad) with sources of technetium-99m was assessed according to NEMA NU-3-2004. Resolution tests were evaluated considering the full width at half maximum (FWHM). The following parameters were evaluated: angular resolution in air, spatial resolution with a scattering medium and in air, energy resolution, and sensitivity and shielding. The collimator was used to evaluate angular and spatial resolution, sensitivity, and shielding. Background radiation was considered and did not affect the counts. Results FWHM of angular resolution (at 3/30 cm) was 39.17°/33.13° with the collimator and 74.08°/71.51° without the collimator; FWHM of spatial resolution in air at 10 mm was 13.32 mm with the collimator and 21.23 mm without the collimator. Energy resolution (%FWHM) was 20.51%. Sensitivity at 10 mm was 4.642±5 cps/MBq without the collimator and 1.063±2 cps/MBq with the collimator; shielding effectiveness of the probe tip was 99.52%. Background was not relevant to the counts. Conclusion We showed that the collimator improved angular and spatial resolution to the detriment of sensitivity. Feasible results of energy resolution, sensitivity, and shielding were achieved.