Modelling the Anatomic Distribution of Neurologic Events in Patients with COVID-19: A Systematic Review of MRI Findings.

BACKGROUND: Neurologic events have been reported in patients with coronavirus disease 2019 (COVID-19). However, a model-based evaluation of the spatial distribution of these events is lacking. PURPOSE: Our aim was to quantitatively evaluate whether a network diffusion model can explain the spread of small neurologic events. DATA SOURCES: The MEDLINE, EMBASE, Scopus, and LitCovid data bases were searched from January 1, 2020, to July 19, 2020. STUDY SELECTION: Thirty-five case series and case studies reported 317 small neurologic events in 123 unique patients with COVID-19. DATA ANALYSIS: Neurologic events were localized to gray or white matter regions of the Illinois Institute of Technology (gray-matter and white matter) Human Brain Atlas using radiologic images and descriptions. The total proportion of events was calculated for each region. A network diffusion model was implemented, and any brain regions showing a significant association (P < .05, family-wise error-corrected) between predicted and measured events were considered epicenters. DATA SYNTHESIS: Within gray matter, neurologic events were widely distributed, with the largest number of events (∼10%) observed in the bilateral superior temporal, precentral, and lateral occipital cortices, respectively. Network diffusion modeling showed a significant association between predicted and measured gray matter events when the spread of pathology was seeded from the bilateral cerebellum (r = 0.51, P < .001, corrected) and putamen (r = 0.4, P = .02, corrected). In white matter, most events (∼26%) were observed within the bilateral corticospinal tracts. LIMITATIONS: The risk of bias was not considered because all studies were either case series or case studies. CONCLUSIONS: Transconnectome diffusion of pathology via the structural network of the brain may contribute to the spread of neurologic events in patients with COVID-19.

Short-limb skeletal dysplasias: evaluation of the fetal spine with sonography and radiography.

Sonograms and radiographs of the lumbar spine in 51 fetuses and neonates with thanatophoric dwarfism, achondroplasia, and osteogenesis imperfecta type II were retrospectively evaluated. Study data included 27 prenatal and 27 neonatal sonograms and radiographs in 40 fetuses and neonates and 11 cases described in the radiology literature. To precisely compare the sonographic and radiographic appearances of platyspondyly in dysplasia, a simple vertebral ratio was obtained from measurement of vertebral interspace and vertebral body height. Normal ranges were obtained from sonograms in 125 normal fetuses and from radiographs in 55 normal fetuses. The severe platyspondyly of thanatophoric dysplasia and the milder platyspondyly of achondroplasia were detected by about 20 menstrual weeks. The vertebral bodies appeared slightly larger on sonograms than on radiographs in both normal fetuses and fetuses with dysplasia.

Chest radiography in infant cardiac allotransplantation.

Heart transplants were performed in seven infants at Loma Linda University Medical Center from 1985 to 1987. Five of these seven patients survived. In this report, the radiographic appearance of the chest is presented before surgery, immediately after surgery, and during a documented episode of rejection. The most current available chest radiograph is also presented. Acute rejection was confirmed by clinical, echocardiographic, and ECG findings. The only pulmonary infection encountered was mycoplasma pneumonitis. Four patients developed gastrointestinal rotavirus infections and were shown to have dilated proximal small-bowel folds on upper gastrointestinal studies. At the time of this writing, the prognosis for the five surviving infants is good. We conclude that the radiographs of infants who have received heart transplants show an unusual cardiac contour and slight cardiomegaly. Increasing cardiomegaly can alert one to early rejection. Prominent folds in the small bowel are of uncertain origin and significance, but they may be related to infection resulting from immunosuppression.

Urokinase therapy for Silastic catheter-induced intravascular thrombi in infants and children.

Among the serious complications encountered with long-term, indwelling Silastic central venous catheters are catheter-induced intravascular thrombi. These thrombi are usually treated by removal of the catheter to prevent thrombus propagation, embolization, or infection. We treated ten patients with urokinase infusion who had experienced 12 incidents of induced intravascular thrombi. Catheter phlebography and two-dimensional echocardiography were used for diagnosis and follow-up. Eleven of the 12 episodes were treated successfully, with complete dissolution of the thrombus. One patient with a calcific thrombus had only partial clot lysis and required catheter removal. By utilizing urokinase infusion to treat Silastic catheter-induced intravascular thrombi, nine of ten central venous catheters were preserved and the possible need for thrombectomy was averted. No serious complications were encountered. In our experience, urokinase therapy has been an effective and safe method for treating Silastic catheter-induced intravascular thrombi.

Rickets associated with cholestasis and parenteral nutrition in premature infants.

Fourteen premature infants on prolonged total parenteral nutrition (TPN) exhibited radiographic evidence of rickets. All had received supplementary doses of vitamin D that, in retrospect, may have been inadequate. Cholestasis and rickets resolved in the 10 surviving infants after they were started on oral feelings, which corrected their hypophosphatemia. On the assumption that they might be deficient in vitamin D, they were given high doses of it. In retrospect, it appears probable that rickets in such cases is caused by hypophosphatemia, due to inadequate phosphorus intake, and that vitamin D deficiency is of little or no importance.

Hemangioendothelioma presenting as posterior mediastinal mass in a child.

A case of a five-month-old child who had a posterior mediastinal mass that was found to be a benign hemangioendothelioma is reported. This is the first reported case of this tumor in this location. Benign hemangioendothelioma should be considered in the differential diagnosis of posterior mediastinal mass in children.

Alteration of perirenal fat secondary to diffuse retroperitoneal infiltration.

Inflammatory effusions and diffuse neoplasia in the fatty retroperitoneal space, which can alter the perirenal fat, can be recognized radiographically because of density differences. The opacity of fluid and tumor accentuates the remaining fat which conforms to the renal contour. This perirenal fatty border appears as a lucent strip when the perirenal fat is not violated and as abnormal perirenal streakiness when the perirenal fat is infiltrated by fluid or tumor. Six cases are described.

Application of aortography and ultrasound in evaluation of renal agenesis.

Ultrasound followed by aortography, if necessary, has been a useful approach in the diagnosis of suspected renal agenesis.

Radiologic signs of the 4p- (Wolf) syndrome.

The improved Giemsa-trypsin banding technique was used to differentiate the 4p- (Wolf) from the 5p- (cri du chat) syndrome. New radiographic findings of polydactyly, cervical ribs, and fusion defects of the elbows, ribs, and spine are presented in a girl with 4p- syndrome with 45 chromosomes and a B4/G22 translocation [45, XX, -4, -22, +t(4p22q)].

Subcutaneous emphysema, pneumomediastinum, and pneumothorax in diabetic ketoacidosis.

The authors report two cases of coexistent pneumomediastinum and diabetic ketoacidosis. One patient had pneumothorax as well. Hyperpnea or vomiting, or a combination of the two, may be the etiologic agent in such cases. The prognosis is excellent and there is prompt regression of the pneumomediastinum following correction of the ketoacidosis.