Anatomical hemispherectomy revisited-outcome, blood loss, hydrocephalus, and absence of chronic hemosiderosis.

PURPOSE: To evaluate microsurgical trans-sylvian trans-ventricular anatomical hemispherectomy with regard to seizure outcome, risk of hydrocephalus, blood loss, and risk of chronic hemosiderosis in patients with intractable seizures selected for surgery using current preoperative assessment techniques. METHODS: Out of 86 patients who underwent hemispherectomy between February 2000 and April 2019, by a single surgeon, at a tertiary care referral center, 77 patients (ages 0.2-20 years; 40 females) who had an anatomical hemispherectomy were analyzed. Five of these were 'palliative' surgeries. One-stage anatomical hemispherectomy was performed in 55 children, two-stage anatomical hemispherectomy after extraoperative intracranial monitoring in 16, and six hemispherectomies were done following failed previous resection. Mean follow-up duration was 5.7 years (range 1-16.84 years). Forty-six patients had postoperative MRI scans. RESULTS: Ninety percent of children with non-palliative hemispherectomy achieved ILAE Class-1 outcome. Twenty-seven patients were no longer taking anticonvulsant medications. Surgical failures (n = 4) included one patient with previous meningoencephalitis, one with anti-GAD antibody encephalitis, one with idiopathic neonatal thalamic hemorrhage, and one with extensive tuberous sclerosis. There were no failures among patients with malformations of cortical development. Estimated average blood loss during surgery was 387 ml. Ten (21%) children developed hydrocephalus and required a shunt following one-stage hemispherectomy, whereas 10 (50%) patients developed hydrocephalus among those who had extraoperative intracranial monitoring. Only 20% of the shunts malfunctioned in the first year. Early malfunctions were related to the valve and later to fracture disconnection of the shunt. One patent had a traumatic subdural hematoma. None of the patients developed clinical signs of chronic 'superficial cerebral hemosiderosis' nor was there evidence of radiologically persistent chronic hemosiderosis in patients who had postoperative MRI imaging. CONCLUSION: Surgical results of anatomical hemispherectomy are excellent in carefully selected cases. Post-operative complications of hydrocephalus and intraoperative blood loss are comparable to those reported for hemispheric disconnective surgery (hemispherotomy). The rate of shunt malfunction was less than that reported for patients with hydrocephalus of other etiologies Absence of chronic 'superficial hemosiderosis', even on long-term follow-up, suggests that anatomical hemispherectomy should be revisited as a viable option in patients with intractable seizures and altered anatomy such as in malformations of cortical development, a group that has a reported high rate of seizure recurrence related to incomplete disconnection following hemispheric disconnective surgery.

MR imaging of the fetal brain at 1.5T and 3.0T field strengths: comparing specific absorption rate (SAR) and image quality.

OBJECTIVES: Our two objectives were to evaluate the feasibility of fetal brain magnetic resonance imaging (MRI) using a fast spin echo sequence at 3.0T field strength with low radio frequency (rf) energy deposition (as measured by specific absorption rate: SAR) and to compare image quality, tissue contrast and conspicuity between 1.5T and 3.0T MRI. METHODS: T2 weighted images of the fetal brain at 1.5T were compared to similar data obtained in the same fetus using a modified sequence at 3.0T. Quantitative whole-body SAR and normalized image signal to noise ratio (SNR), a nominal scoring scheme based evaluation of diagnostic image quality, and tissue contrast and conspicuity for specific anatomical structures in the brain were compared between 1.5T and 3.0T. RESULTS: Twelve pregnant women underwent both 1.5T and 3.0T MRI examinations. The image SNR was significantly higher (P=0.03) and whole-body SAR was significantly lower (P<0.0001) for images obtained at 3.0T compared to 1.5T. All cases at both field strengths were scored as having diagnostic image quality. Images from 3.0T MRI (compared to 1.5T) were equal (57%; 21/37) or superior (35%; 13/37) for tissue contrast and equal (61%; 20/33) or superior (33%, 11/33) for conspicuity. CONCLUSIONS: It is possible to obtain fetal brain images with higher resolution and better SNR at 3.0T with simultaneous reduction in SAR compared to 1.5T. Images of the fetal brain obtained at 3.0T demonstrated superior tissue contrast and conspicuity compared to 1.5T.

MR venography of the fetal brain using susceptibility weighted imaging.

PURPOSE: To evaluate the feasibility of performing fetal brain magnetic resonance venography using susceptibility weighted imaging (SWI). MATERIALS AND METHODS: After obtaining informed consent, pregnant women in the second and third trimester were imaged using a modified SWI sequence. Fetal SWI acquisition was repeated when fetal or maternal motion was encountered. The median and maximum number of times an SWI sequence was repeated was four and six respectively. All SWI image data were systematically evaluated by a pediatric neuroradiologist for image quality using an ordinal scoring scheme: 1. diagnostic; 2. diagnostic with artifacts; and 3. nondiagnostic. The best score in an individual fetus was used for further statistical analysis. Visibility of venous vasculature was also scored using a dichotomous variable. A subset of SWI data was re-evaluated by the first and independently by a second pediatric neuroradiologist. Kappa coefficients were computed to assess intra-rater and inter-rater reliability. RESULTS: SWI image data from a total of 22 fetuses were analyzed. Median gestational age and interquartile range of the fetuses imaged were 32 (29.9-34.9) weeks. In 68.2% of the cases (n = 15), there was no artifact; 22.7% (n = 5) had minor artifacts and 9.1% (n = 2) of the data was of nondiagnostic quality. Cerebral venous vasculature was visible in 86.4% (n = 19) of the cases. Substantial agreement (Kappa = 0.73; 95% confidence interval 0.44-1.00)) was observed for intra-rater reliability and moderate agreement (Kappa = 0.48; 95% confidence interval 0.19-0.77) was observed for inter-rater reliability. CONCLUSION: It is feasible to perform fetal brain venography in humans using SWI.

An Atypical Radiologic Presentation of Right Sixth Lateral Rectus Palsy: A Case Report.

Isolated ocular palsies are often associated with a benign process in the pediatric population but early diagnosis is critical to exclude any serious pathology. In this case, a six-year-old female with no significant past medical history presented with isolated right-eye medial deviation. The patient reported right-eye medial deviation for the past several weeks and associated double vision, but denied any pain with eye movements, other cranial nerve changes, or headaches. This case highlights the key radiologic finding which may ultimately allow for a leading diagnosis and inform further management in cases of isolated ocular nerve palsy.

MR imaging findings of retinal hemorrhage in a case of nonaccidental trauma.

Retinal hemorrhage is a well-recognized manifestation of child abuse found in many babies with shaken baby syndrome. The presence of retinal hemorrhage is generally associated with more severe neurological damage and a worse clinical outcome. MR imaging findings of retinal hemorrhages are not well described in the pediatric literature. We present a 6-month-old boy with new-onset seizures, subdural hemorrhage and bilateral retinal hemorrhages that were detected by MRI and confirmed by indirect ophthalmoscopy. This case demonstrates the MR imaging findings of retinal hemorrhages and the importance of radiologists being able to recognize these specific imaging features.

Transient small bowel intussusceptions: ultrasound findings and clinical significance.

PURPOSE: To study the ultrasound (US) findings and clinical significance of transient small bowel intussusceptions (TSBI) in adults and children. METHODS: Clinical records and US findings of 108 consecutive patients of intestinal intussusception diagnosed on US between August 1995 and August 2004 were reviewed. In all cases, the length, diameter, wall thickness and color Doppler study of the bowel segment involved in intussusception were evaluated. Subsequent follow-up scans were performed at 30 min, 3 days and 2 weeks. Patients were clinically followed up for 6 months. RESULTS: Forty-one patients were diagnosed as TSBI. Thirty-six intussusceptions were incidentally detected during US performed for some unrelated disease or vague abdominal symptom. Five patients presented with signs of obstruction at the time of the initial US diagnosis; however, the intussusceptions resolved without any treatment and were not detected on follow-up scans. Sixty-seven symptomatic patients required surgical intervention. CONCLUSION: Incidentally detected, small bowel intussusceptions without an identifiable pathological lead point, with a normal wall thickness, a length of less than 3.5 cm, normal nondilated proximal bowel and normal vascularity on color Doppler reduce spontaneously and are of no clinical significance.

Ultrasound in the diagnosis of typhoid fever.

OBJECTIVES: To establish the efficacy of ultrasound (US) of the abdomen as a diagnostic test in Typhoid. To determine the ultrasound diagnostic criteria in cases of Typhoid. METHODS: The Widal test is the most commonly used method of detecting Typhoid fever, but does not provide results until a week after onset of fever due to the need for enough antibodies to develop to render a positive result. Abdominal Ultrasound was performed within three days of the onset of fever in 80 cases suspected to be having Typhoid fever. Subsequent follow-up scans were performed at five days, ten days and fifteen days. Subsequently, all 80 cases were found to be Widal positive and Salmonella culture was positive in 32 cases. We present our findings in 26 patients in the age group between 4 to 20 years in whom both Widal test and Salmonella culture was subsequently positive. RESULTS: The US findings were as follows: splenomegaly (n-26, 100%); Bowel wall thickening (n-22, 85%); mesenteric lymphadenopathy(n-20,77%); hepatomegaly with normal parenchymal echotexture (n-8, 31%); thickened gall bladder (n-16, 62%); biliary sludge (n-6, 23%); positive US Murphy's sign (n-7, 27%); pericholecystic edema with increased vascularity (n-6, 23%); mucosal ulceration in the wall of the gall bladder (n-1, 3.8%). CONCLUSION: In endemic areas like India, ultrasound findings of hepatomegaly, splenomegaly, ileal and cecal thickening, mesenteric lymphadenopathy and thick-walled gallbladder are diagnostic features of typhoid. Ultrasound can be a non-invasive, economical and a reasonably sensitive tool for diagnosing typhoid when serology is equivocal and cultures are negative.