Reversal of diastolic cerebral blood flow in infants without brain death

The reversal of diastolic cerebral blood flow has been regarded as a characteristic waveform of brain death and a useful confirming sign. We report 2 patients who had diastolic flow reversal but survived. One, a 1-month-old boy with status epilepticus, had reversal of diastolic cerebral blood flow detected by Doppler ultrasound soon after admission. Reversal disappeared after medical management for increased intracranial pressure and seizure control. He recovered without sequelae. The other, a 6-month-old girl with choroid plexus papilloma, had reversal of diastolic flow during abrupt clinical deterioration. Emergent surgical removal of the tumor was performed and she survived with hemiparesis and psychomotor retardation. Our patients demonstrated that even in the presence of diastolic reversal of cerebral blood flow, prompt and effective treatment can avoid a fatal outcome.     

Laparoscopic nephrectomy in a porcine model.

Laparoscopic nephrectomy was performed in 15 male pigs, the procedure was successful in 14. Extraction of the intact kidney through a 5-cm lower abdomen incision was done in 7 animals; complete destruction and evacuation of the kidney was accomplished by a round-knife suction device through a 1-cm port in another 7 pigs. Grossly, the specimen consisted of sausage-like tubular renal tissue and a small amount of tissue debris. Pathology revealed that the glomerular and tubular structures were well preserved, no interstitial hematoma could be found. Four ports were usually used, one 1-cm umbilical camera port, one 0.5-cm port for ureter traction, and two 1-cm working ports along the midclavicular line. All the pigs recovered uneventfully. The average operation time was 3 h 20 min. The application of endo-GIA (United States Surgical Corporation) for renal hilum reduced the operative time to 2 h 20 min. Complications included renal vein tear during endoclip application and cutting in the first case, mild subcutaneous emphysema in 2 cases. This first pig received exploratory laparotomy for the repair and ligation of the renal vein. No more major complications occurred with increasing experience. From this porcine experiment, we conclude that the combination of laparoscopy, a tissue destroyer and an endobag for the entrapment of kidney seem to be a promising technique for clinical nephrectomy.     

Evaluation of variable line-shape models and prior information in automated 1H spectroscopic imaging analysis.

Analysis of in vivo short TE 1H spectra is complicated by broad baseline signal contributions and resonance line-shape distortions. Although the assumptions of ideal metabolite resonance line-shapes and slowly varying baseline signals can be used to separate these signals, the presence of broad or asymmetric line-shapes can invalidate this model. More complex line-shape models are computationally expensive or difficult to constrain, particularly for the low signal-to-noise commonly found for in vivo MR spectroscopic imaging applications. In this study, two time-domain models for fitting variable spectral line-shapes are examined, one using B-splines and another using summed sinusoids. The methods were verified using both phantom and human data, and Monte Carlo simulations were used to evaluate variations in calculated metabolite amplitudes due to interactions between the baseline and line-shape estimations. Additional studies investigated the use of prior line-shape information, obtained from either a water MRSI measurement or calculations from B(0) maps, to determine parameter starting values or optimization constraints. Both line-shape models showed the ability to fit the variety of line-shapes present in both the phantom and human MRSI data, with similar or improved accuracy over a Gaussian line-shape model; however, this improvement resulted in only minor improvement for the high-SNR phantom data and moderate improvements in regions with asymmetry for the fitted in vivo metabolite images. The use of prior line-shape information was of most benefit when applied toward setting optimization constraints but was of limited benefit when used to define initial starting values.     

Using a dense PTFE membrane without primary closure to achieve bone and tissue regeneration.

The most common types of barrier membranes used for bone or tissue regeneration are made of expanded-polytetrafluoroethylene (e-PTFE) or resorbable materials, such as collagen. Both the e-PTFE and resorbable membranes require primary soft tissue coverage. This article explores the use of a dense-polytetrafluoroethylene (d-PTFE) membrane, which does not require primary soft tissue coverage. The advantages of d-PTFE in contrast to the other more commonly used types of barrier membranes and the clinical significance of these advantages for implant surgical and restorative treatment are discussed.     

Disseminated histoplasmosis with oral manifestation

Histoplasmosis is a fungal disease that affects humans and is caused by Histoplasma capsulatum. The presentation of the infection may be acute, chronic, or disseminated. The disseminated form has extrapulmonary manifestations which may include oral manifestation a. A patient with AIDS sought treatment and he had disseminated histoplasmosis with oral manifestations. The purpose of this case report and literature review is to emphasize the role the dental team has in the diagnosis of disseminated disease when a patient presents with oral manifestations associated with the disease. This case report is clinically relevant because it is not uncommon for oral manifestations to be one of the first signs of systemic disease.