Review of technology: planning for the development of telesonography.

Teleradiology allows contemporaneous interpretation of imaging exams performed at some distance from the interpreting radiologist. The transmitted images are usually static. However, there is benefit to real-time review of full-motion ultrasound (US) exams as they are performed. Telesonography is transmission of full-motion sonographic data to a remote site. We hypothesize that US exams, read after having been compressed utilizing Motion Picture Experts Group version 4 (MPEG-4) compression scheme, transmitted over the Internet as streaming multimedia, decompressed, and displayed, are equivalent in diagnostic accuracy to reading the examinations locally. MPEG-4 uses variable compression on each image frame to achieve a constant output bit rate. With less compression, the bit rate rises, and the only way the encoder can contain bit rate within the set bandwidth is by lowering frame rate or reducing image quality. We review the relevant technologies and industry standard components that will enable low-cost telesonography.

Bladder wall necrosis in an extremely low-birth-weight infant: a thought-provoking complication of necrotizing enterocolitis.

An 879-g baby boy had catastrophic necrotizing enterocolitis (NEC) at 29 days of life and underwent surgical laparotomy with a subsequent ileostomy and peritoneal drain placement. The infant was subsequently stable until 42 days of life when a spontaneous perforation of the bladder apex was diagnosed by a suprapubic cystogram. Laparotomy on day of life 46 found a loop of dead bowel herniating into a necrotic hole of the bladder dome. This case shows a previously unreported complication of NEC and discusses the possibility that prolonged use of a peritoneal drain may have permitted its genesis.

Imaging the lungs in asthmatic patients by using hyperpolarized helium-3 magnetic resonance: assessment of response to methacholine and exercise challenge.

BACKGROUND: Imaging of gas distribution in the lungs of patients with asthma has been restricted because of the lack of a suitable gaseous contrast agent. Hyperpolarized helium-3 (HHe3) provides a new technique for magnetic resonance imaging of lung diseases. OBJECTIVE: We sought to investigate the use of HHe3 gas to image the lungs of patients with moderate or severe asthma and to assess changes in gas distribution after methacholine and exercise challenge. METHODS: Magnetic resonance imaging was performed in asthmatic patients immediately after inhalation of HHe3 gas. In addition, images were obtained before and after methacholine challenge and a standard exercise test. RESULTS: Areas of the lung with no signal or sharply reduced HHe3 signal (ventilation defects) are common in patients with asthma, and the number of defects was inversely related to the percent predicted FEV(1) (r = 0.71, P <.002). After methacholine challenge (n = 3), the number of defects increased. Similarly, imaging of the lungs after exercise (n = 6) showed increased ventilation defects in parallel with decreases in FEV(1). The increase in defects after challenge in these 9 asthmatic patients was significant both for the number (P <.02) and extent (P <.02) of the defects. The variability and speed of changes in ventilation and the complete lack of signal in many areas is in keeping with a model in which the defects result from airway closure. CONCLUSION: HHe3 magnetic resonance provides a new technique for imaging the distribution of inhaled air in the lungs. The technique is suitable for following responses to treatment of asthma and changes after methacholine or exercise challenge.

Extravasation of hyperalimentation into the liver parenchyma from a peripherally inserted central catheter.

A neonate receiving hyperalimentation through a peripherally inserted central catheter (PICC) had acute abdominal distension and respiratory distress. She was found to have extravasated a 9-cm x 9-cm pocket of hyperalimentation into the liver parenchyma, most likely caused by arterial placement of the PICC. She had severe anasarca and markedly decreased synthetic liver function. After 3 weeks of intensive care, she began to diurese. Her respiratory status subsequently improved, she started feeding, and her liver function test results returned to normal. This case shows the remarkable regenerative capacity of the neonatal liver and provides a rationale for conservative management of this rare but morbid PICC complication.