Biomedical subjects
Publications and source records attributed to J Jallo.
We report successful treatment of opioid-resistant postoperative pain in this case report. Oral ketamine reduced the doses of opioids needed for pain control. Opioid/N-methyl-D-aspartate receptor antagonist combinations should be studied further for acute pain treatment.
In an effort to study changes in cerebral blood flow (CBF), intracranial pressure (ICP) and intracranial compliance (ICC) simultaneously, we have developed a chronic model in rats using a pial window crown with two ports. This model can also be used to study vasoreactivity of pial vessels. Female Sprague-Dawley rats weighing between 225-250 g underwent placement of cranial chamber with dual ports under pentobarbital anesthesia. To test the utility of this technique 45 groups of rats were studied. Group 1 consisted of control animals. Group 2 consisted of rats undergoing 15 min of global cerebral ischemia. Rats in group 3 were evaluated for changes in vessel diameter and ICP after adenosine injection. In group 4 leukocyte/endothelial interactions were evaluated. These groups demonstrate the ability of this model to monitor CBF, ICP, ICC and pial vessel architecture in chronic rat experiments.
BACKGROUND: Chordomas are tumors of notochordal origin that account for approximately 1%-4% of all primary malignant bone tumors. The majority of patients with chordomas have a poor surgical prognosis due to extent of disease at diagnosis. These lesions have been previously classified based solely on their location. METHODS: We describe here a case report of a posterior epidural C5-T1 chordoma that was discovered in a young patient who presented with weakness and paresthesia in all four extremities. This lesion was notable for its extraosseous and extradural characteristics. RESULTS: C5-T1 laminectomy with gross total resection of the mass led to complete resolution of all symptoms. There has been no evidence of tumor recurrence to date. CONCLUSIONS: We propose here a new classification system for chordomas that emphasizes the difference in resectability of these lesions depending on the space they occupy and the presence or absence of an osseous connection.
Alterations in leukocyte/endothelium interaction due to phototoxic effects of the fluorescent dyes acridine orange (AO) and rhodamine 6G (Rh6G) were studied by intravital microscopy using the dorsal skinfold model in awake Syrian golden hamsters. AO (0.5 mg/kg/min; constant IV infusion) and Rh6G (0.1 micromol/kg; bolus IV) were administered via an indwelling venous catheter. Five to seven arterioles (35-55 microm) and postcapillary venules (30-65 microm) were investigated in each animal. Vessels were exposed four times for 30 sec to continuous light of the appropriate excitation wavelength with a 10-15-min time interval between exposures. Animals were randomly assigned to five experimental groups (five distinct light energy levels). AO and Rh6G induced leukocyte rolling/sticking in postcapillary venules and arterioles when exposed to high light energy levels. AO, but not Rh6G, induced arteriolar vasospasm when exposed to high light energies. The potential phototoxic effect of AO and Rh6G is demonstrated, as assessed by the stimulation of leukocyte-endothelium interaction and arteriolar vasospasm in vivo. This study underscores the necessity to optimize microscopic set-ups for intravital microscopy, to reduce the excitation light energy level significantly, and to perform stringent control experiments, ruling out an artificial phototoxicity-induced stimulation of leukocyte adhesion.
A 13-year-old female presented with acute left gaze paralysis. MRI revealed hydrosyringomyelia (HSM) with syringobulbia in the left pons extending cephalad into the centrum semiovale. A suboccipital craniotomy was performed and the foramen of Magendie was imperforate. Ocular movements normalized in 2 months and postoperative MRI confirmed resolution of the cerebral syrinx and syringobulbia and diminished HSM. This case represents an extreme example of the altered spinal fluid dynamics with Chiari I malformation. Theories on HSM are reviewed.
The authors recently treated three cases involving fractures of the occipital condyle. First described by Bell in 1817, this lesion has proven to be very rare, with only 32 cases previously reported in the literature. Plain films often do not reveal any abnormality, making diagnosis difficult. High-resolution computed tomography has been demonstrated to be very sensitive in diagnosing this lesion. This fact was borne out in the authors' series. All of the authors' patients were managed either with a Philadelphia collar or with halo fixation, with excellent outcomes.