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Phuong, Loi K.

Mayo Clinic

Mayo Clinic

Citations 3

Management of Intracranial Infectious Aneurysms: A Series of 16 Cases
Phuong, Loi K., Link, Michael J. , Barrow, Daniel L. , Wijdicks, Eelco F. M. , Barrow, Daniel L

Neurosurgery | July 30, 2004 | Volume: 51 | Issue: 5 | Pages: 1145-1152

10.1097/00006123-200211000-00008 Get It

Abstract OBJECTIVE The purpose of this study was to better define the management of intracranial infectious aneurysms. METHODS We present a retrospective review of the management of 16 patients with intracranial infectious aneurysms. The mean follow-up period was 86 months. RESULTS None of the patients had a rehemorrhage during antibiotic treatment. The mortality and long-term outcome from ruptured intracranial infectious aneurysms may be better than previously thought. There was no significant difference in long-term outcome between patients with single or multiple infectious aneurysms or between patients who underwent surgical resection and those who were treated only with antibiotics. CONCLUSION Operative treatment should be pursued for patients with ruptured infectious aneurysms. Patients with unruptured intracranial infectious aneurysms should be observed during antibiotic therapy and followed up with cerebral angiography. Surgical resection should be considered if the aneurysm enlarges and the patient's general medical condition allows general anesthesia to be tolerated.
Natural History of Tethered Cord in Patients with Meningomyelocele
Phuong, Loi K., Schoeberl, Kimberly A., Raffel, Corey

Neurosurgery | July 30, 2004 | Volume: 50 | Issue: 5 | Pages: 989-995

10.1097/00006123-200205000-00011 Get It

AbstractOBJECTIVE:The purpose of this study was to describe the natural history of tethered cord in patients who have undergone meningomyelocele repair.METHODS:We performed a retrospective review of 45 patients with a history of neonatal meningomyelocele repair who subsequently developed symptoms of tethered cord. Symptoms of tethered cord in this cohort consisted of the development of bladder spasticity or orthopedic foot deformity. None of these patients were treated with cord untethering; instead, they were treated symptomatically.RESULTS:On follow-up, 40 (88.9%) of these patients subsequently required additional orthopedic or urological procedures because of further symptoms of tethered cord. The incidence of progression of tethered cord syndrome is 27.5, 40, and 60% at 1, 2, and 5 years, respectively.CONCLUSION:Although this study does not address the question whether cord untethering will prevent further symptom development, these results do provide a strong rationale for consideration of an untethering procedure in patients with repaired meningomyelocele at the time of the onset of symptoms of tethered cord.
High-dose Trigeminal Neuralgia Radiosurgery Associated with Increased Risk of Trigeminal Nerve Dysfunction
Pollock, Bruce E. , Phuong, Loi K., Foote, Robert L. , Stafford, Scott L., Gorman, Deborah A.

Neurosurgery | July 30, 2004 | Volume: 49 | Issue: 1 | Pages: 58-64

10.1097/00006123-200107000-00008 Get It

Abstract OBJECTIVE Stereotactic radiosurgery is being used with more frequency in the management of patients with trigeminal neuralgia. To improve facial pain outcomes, many centers have increased the prescribed radiation dose to the trigeminal nerve. METHODS Between April 1997 and December 1999, 68 patients underwent radiosurgery for trigeminal neuralgia with use of the Leksell gamma knife (Elekta Instruments, Norcross, GA) and a single 4-mm isocenter of radiation. Twenty-seven patients (40%) received 70 Gy (low dose) of irradiation and 41 patients (60%) received 90 Gy (high dose). The groups were similar with regard to age, sex, duration of pain, number of prior surgeries, and preexisting trigeminal deficits. The primary facial pain outcomes for analysis were excellent (pain-free, no medications) and good (pain-free, reduced medications). The mean length of follow-up after radiosurgery was 14.4 months (range, 2–36 mo). RESULTS At last follow-up examination, 11 (41%) of the 27 patients with low-dose radiosurgery remained pain-free compared with 25 (61%) of the 41 patients with high-dose radiosurgery (P = 0.17). Additional surgery was performed in 12 low-dose patients (44%) and 8 high-dose patients (20%) (P = 0.05). High-dose radiosurgery was associated with an increased rate of permanent trigeminal nerve dysfunction (54% versus 15%, P = 0.003). Bothersome dysesthesias occurred in 13 high-dose patients (32%), whereas only 1 low-dose patient had this complication (P = 0.01). Three high-dose patients (8%) developed corneal numbness after radiosurgery. Pain recurred with more frequency in patients not developing trigeminal nerve dysfunction after radiosurgery (9 of 22 patients, 41%) compared with those who sustained facial numbness, paresthesias, or dysesthesias (4 of 27 patients, 15%); however, the difference was not statistically significant (P = 0.08). CONCLUSION Higher doses of radiation may correlate with better facial pain outcomes after radiosurgery for trigeminal neuralgia. However, the incidence of significant trigeminal nerve dysfunction is markedly increased after radiosurgery for patients receiving high-dose radiosurgery. Because of the nonselective nature of this ablative technique, dose prescription should be limited to less than 90 Gy.