Perfusional evaluation of postesophagectomy gastroplasty with a radioisotopic study.

SUMMARY: Anastomotic fistula represents one of the frequent causes of postoperative morbidity and mortality following transhiatal esophageal resections. The main etiological factor is the ischemia of the gastric tube created for digestive transit reconstruction. Evidence suggests that per operative hypoperfusion can be maintained or even impaired after the surgery. Several methods have been employed in an attempt to assess the blood perfusion of the gastric flap, but they all pose limitations. However, there is a chronological relationship between perfusion assessments, which are almost exclusively performed per operatively, and the occurrence of a leak, which commonly appears several days after the surgery. The authors have developed a method of gastric perfusion evaluation by single photon emission computed tomography scintigraphy, which corrects that temporal matter, allowing the estimation of postoperative gastric perfusion. It is noninvasive, low cost, and may be applied by the time frame when most fistulas occur. High correlation between the event fistula and the low radiotracer uptake in the group of studied patients could be demonstrated. A role in the research of perfusion evaluation of different types of esophageal reconstruction is suggested.

Localization of the epileptogenic zone by ictal and interictal SPECT with 99mTc-ethyl cysteinate dimer in patients with medically refractory epilepsy.

PURPOSE: To evaluate the accuracy, feasibility and clinical value of both ictal and interictal 99mTc-ethyl cysteinate dimer (ECD) single photon emission computed tomography (SPECT) in patients with medically refractory epilepsy. METHODS: The study included 75 consecutive patients, 48 with temporal lobe epilepsy (TLE group), and 27 with extratemporal epilepsy (ExT group). The accuracy of SPECT was analyzed considering the final diagnosis reached by convergence of clinical, electrophysiologic, structural, pathologic and outcome data. RESULTS: Ictal SPECT correctly identified the epileptogenic zone in 21 (91.3%) of 23 patients, whereas interictal SPECTs could correctly identify the epileptogenic zone in only 41 (62.1%) of 66 patients (chi2 = 5.56, df = 1, p < 0.05). Results were similar when the two study groups were analyzed separately. Moreover, ictal studies had significantly higher specificity (91.3 vs. 60.6%) and positive predictive value (91.3 vs. 66.2%) than interictal studies for the whole series of patients. Considering all tools used in the preoperative workup of these patients, ictal SPECT significantly contributed to the final topographic diagnosis in seven of 14 patients from TLE group and in six of nine patients from the ExT group. In these patients, ictal SPECT either obviated the need for invasive EEG or helped to define where to concentrate the efforts of invasive investigation. CONCLUSIONS: These data demonstrate that ictal SPECT can be easily achieved by using 99mTc-ECD and can accurately localize the epileptogenic zone in both temporal and extratemporal epilepsies. Ictal ECD SPECT proved to be significantly more sensitive and specific than interictal ECD SPECT, and clinically useful in the definition of the epileptogenic zone.

Ventriculografia radioisotopica en repouso e durante esforço: valores normais / Radioisotopic ventriculography at rest and during effort: normal values

A ventriculografia radioisotopica e uma tecnica de medicina nuclear que vem sendo utilizada, particularmente no diagnostico da doenca coronaria. A maior sensibilidade e especificidade deste metodo, em relacao a eletrocardiografia de esforco, ja foi estabelecida. Esta tecnica avalia a funcao ventricular esquerda em repouso e durante esforco, a partir da administracao de um tracador radioativo (99m Tc-hemacia) que permanece no compartimento vascular. Para melhor valorizar a resposta ventricular ao esforco nos pacientes com coronariopatia, foram determinados os valores normais em nosso servico. Estudaram-se 20 voluntarios, sem evidencia clinica de cardiopatia e com teste ergometrico normal. Todos submeteram-se a um exercicio adequado (produto da frequencia cardiaca pela pressao arterial sistolica superior a 25000) sendo obtida uma fracao de ejecao media do ventriculo esquerdo em repouso de 54,1% + ou - 6,1% e durante exercicio, de 65,6% + ou - 7,6%. A variacao com o esforco atingiu 21,3% + ou - 8,9%. Os resultados, no grupo masculino, estao em concordancia com os apresentados por outros investigadores, os quais nao relatam um numero significativo de estudos em mulheres. O grupo feminino apresentou valores da fracao de ejecao significativamente inferiores aos dos homens-repouso (p < 0,05) e esforco (p<0,01) sendo, no entanto, as variacoes porcentuais entre os resultados de repouso e esforco similares (NS) entre os sexos