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Biomedical subjects

Michael R Harrison

Publications and source records attributed to Michael R Harrison.

45 records · Page 3Linked to original sources
PubMed2002

Fetal endoscopic surgery: lessons learned and trends reviewed.

PURPOSE: Fetal surgery is performed increasingly with minimal access approaches. The authors report their experience with fetal endoscopic procedures (fetendo) with emphasis on changing techniques and outcome trends. METHODS: All fetal endoscopic cases performed at a single institution from January 1996 to August 2001 were reviewed (n = 66). Cases were examined with respect to year performed, type of operation, operative data, and outcome. RESULTS: Twin-twin transfusion syndrome (26 cases) and congenital diaphragmatic hernia (35 cases) were the most common diseases treated. From 1996 to 2001, there was a decrease in average operating time (256 to 127 minutes [P =.0006]), number of ports utilized (3.8 to one [P =.00001]), pump volume (28.7 to 2.7 L [P =.00001]), and estimated blood loss (408 to 29 mL [P =.008]). In addition, port size changed from 10 mm to 5 mm. Chorioamniotic separation (31 of 66), premature rupture of membranes (32 of 66), chorioamnionitis (12 of 66), and fetal death (10 of 66) continued to be significant complications. CONCLUSIONS: Fetal endoscopic surgery over the last 6 years has evolved toward shorter operating time, the use of smaller and fewer ports, decreased pump fluid exchange, and decreased blood loss, with the types of cases centered on twin-twin transfusion syndrome and congenital diaphragmatic hernia.

Endoscopy↗
PubMed2002

Selective reduction of acardiac twin by radiofrequency ablation.

OBJECTIVE: Acardiac/acephalic twinning is a rare anomaly in which a normal "pump" twin perfuses an acardiac twin, which results in twin reversed arterial perfusion sequence. A novel technique for selective reduction and obliteration of blood flow in the acardiac twin is described. STUDY DESIGN: Thirteen consecutive cases of monochorionic twin gestation with twin reversed arterial perfusion sequence underwent selective reduction of the abnormal twin with the use of radiofrequency ablation. Under direct real-time sonographic guidance, a 3-mm (14-gauge) radiofrequency ablation needle was percutaneously inserted through the maternal abdominal wall into the intrauterine fetal abdomen at the level of the cord insertion site of the acardiac twin. Energy was applied until termination of blood flow to the acardiac fetus was documented by Doppler ultrasound scanning. RESULTS: All 13 mothers tolerated the procedure without major complications. All 13 "pump" fetuses have been delivered. Twelve of 13 infants are alive and well. The first patient in this series was delivered at 24.4 weeks and the infant subsequently died from complications of prematurity. Average gestational age at intervention was 20.7 weeks, and the average gestational age at delivery was 36.2 weeks. CONCLUSION: Radiofrequency ablation is a minimally invasive, percutaneous technique that can effectively obliterate blood supply to an acardiac twin to preserve and protect the pump twin.

Adult↗
PubMed2002

The "diaphanous" diaphragm: a radiographic sign seen after patch repair of congenital diaphragmatic hernia in neonates.

OBJECTIVE: The purpose of this study was to describe the radiographic features and etiology of the "diaphanous" (translucent) diaphragm. This sign, which, to our knowledge, has not previously been described, is a transient phenomenon seen on chest radiographs, after surgical patch repair of congenital diaphragmatic hernia. CONCLUSION: The diaphanous diaphragm is a consequence of air trapped in the porous polytetrafluoroethylene graft that creates an intragraft radiolucency apparent on postoperative chest radiographs obtained within the first 24 hr. This radiolucency is transient and gradually disappears over the first few postoperative days as the air is replaced by granulation tissue. This sign should be recognized and not mistaken for a persistent pneumothorax after repair of a congenital diaphragmatic hernia.

Diagnosis, Differential↗
PubMedDate not supplied

Chorioamniotic membrane separation following fetal surgery.

OBJECTIVE: As the volume of fetal surgery cases has steadily increased, an increasing incidence of chorioamniotic membrane separation (CMS) has been noted. Due to the potential adverse consequences from this abnormality, we reviewed the last decade of experience with fetal intervention at our institution and examined the incidence and outcomes of fetuses given this diagnosis. STUDY DESIGN: A retrospective chart review of 75 fetal surgery cases at our institution was performed. Variables analyzed included preoperative, operative, and outcome data. Postoperative ultrasounds were evaluated for the presence of CMS. RESULTS: Excluding operative deaths, the incidence of CMS was 47%. There were significant differences (p<0.05) in time to delivery (7 vs 5 weeks), cases using a perfusion pump (80% vs 60%), and number of trocars (2.13 vs 1.54) in cases of CMS versus those without. Ultrasounds showed normal to high levels of amniotic fluid in 97% of cases. There was an increased incidence of premature rupture of membranes (63% vs 45%), preterm labor (57% vs 38%), and chorioamnionitis (29% vs 15%) with CMS, but no difference in mortality rate. CONCLUSION: CMS is a frequent finding following fetal surgery. It is associated with significant morbidity but is manageable with close follow-up in a hospital setting. Following fetal surgery, the finding of CMS can be a life-threatening complication that warrants further study to understand its etiology and prevention.

Amnion↗
PubMedDate not supplied

Successful fetal intervention for congenital high airway obstruction syndrome.

INTRODUCTION: Complete congenital high airway obstruction syndrome (CHAOS) usually leads to stillbirth or death within minutes of delivery. We describe the management and long-term follow-up of a baby with a prenatally diagnosed airway obstruction. CASE: Because of progressive hydrops fetalis, massive ascites and everted diaphragms due to CHAOS in a fetus at 24 weeks of gestation, a fetal tracheostomy was performed. Persistent fetal bradycardia at the time of the fetal procedure led to delivery of the infant. Adequate oxygenation and ventilation were attained using relatively low oxygen concentrations and low ventilatory pressures. Plain radiographs demonstrated that the lungs were large and the ribs thin. The infant has a permanent tracheostomy, required continuous assisted ventilation for several months and assisted ventilation at night at home for 3 years. At 4 years of age, he has no speech, all feedings are by gastrostomy, and developmentally he is mildly to moderately delayed. CONCLUSION: Laryngeal atresia produced over-distended lungs and hydrops. Precise prenatal imaging and fetal surgical strategies may allow the survival of affected fetuses.

Adult↗
PubMedDate not supplied

Prenatal resection of a fetal pericardial teratoma.

OBJECTIVE: Pericardial teratomas are rare congenital tumors which invade the developing mediastinum, compressing the venous return to the heart, leading to hydrops. Tumors, with large cystic components, have been treated previously with in utero pericardiocentesis with some success. We present the first reported case of in utero open resection of a fetal pericardial teratoma. METHODS: A 31-year-old G1P0 woman was found to have a fetus with a pericardial teratoma. Hydrops developed at 24 weeks' gestation. After counseling, open fetal resection was performed via a fetal median sternotomy. RESULTS: Although the tumor was successfully removed, the hydrops did not resolve. In addition, over the course of 3 weeks, the mother developed maternal mirror syndrome which prompted an emergent cesarean section. Neonatal death ensued shortly after birth. CONCLUSIONS: The fetus with a pericardial teratoma complicated by hydrops is compromised. Treatment options include early delivery, aspiration of the pericardial effusion, and in utero operative resection.

Adult↗
PubMedDate not supplied

Giant fetal hepatic hemangioma. Case report and literature review.

The purpose of this case report is to demonstrate the importance of prenatal imaging for treatment management of fetal giant hepatic hemangiomas. Prenatal ultrasound revealed an abdominal mass with several cystic areas and punctate calcifications in a fetus at 29 weeks' gestation. Doppler scans confirmed the highly vascular nature of the mass. In this case, ultrasound diagnosed the mass was of hepatic origin, while magnetic resonance imaging at 32 weeks' gestation was more equivocal with respect to the anatomy source of the lesion. Imminent hydrops caused by a rapidly enlarged liver tumor was sonographically demonstrated at 34 weeks' gestation. An elective C-section and immediate tumor resection was performed. At the age of 20 months the infant is thriving. This case supports the notion that the survival rates for giant hepatic hemangiomas improve when fetal hydrops is averted and specific pre- and postnatal treatment is applied based on correct prenatal imaging diagnostics.

Adolescent↗
PubMedDate not supplied

The University of California at San Francisco Fetal Treatment Center: a personal perspective.

Today, the Fetal Treatment Center at the University of California, San Francisco is premier not only for its innovative and cutting-edge developments in fetal diagnosis and therapy, but in its delivery of excellent clinical care to patients from within and outside the United States. Indeed it is recognized as the pioneering institution for fetal surgery. But, the road to success and international recognition has been torturous and often tumultuous. From a personal perspective, Dr. Michael Harrison recounts the center's 25-year history--an evolution that has seen a 'California fault zone' become an epicenter of excellence for fetal therapy. Along the way, Dr. Harrison recalls the best and worst of times in the center's history particularly as they relate to fetal surgery, recalls the initial principal payers and subsequent cadre of professionals responsible for developing the center and providing the medical and surgical expertise that is the hallmark of the UCSF Fetal Treatment Center, provides a subjective assessment, a 'report card', of where they stand in fetal therapy today, and finally, gives well-deserved credit to the many talented research fellows, whom he calls the 'heart and soul' of the enterprise, whose 'fingerprints' are borne on all the advances in fetal treatment.

Academic Medical Centers↗