Lumbar Puncture Test in Normal Pressure Hydrocephalus: Does the Volume of CSF Removed Affect the Response to Tap?

BACKGROUND AND PURPOSE: There is limited evidence to support the use of high-volume lumbar taps over lower-volume taps in the diagnosis of normal pressure hydrocephalus. The purpose of this study is to detect whether the volume of CSF removed from patients undergoing high-volume diagnostic lumbar tap test for normal pressure hydrocephalus is significantly associated with post-lumbar tap gait performance. MATERIALS AND METHODS: This retrospective study included 249 consecutive patients who underwent evaluation for normal pressure hydrocephalus. The patients were analyzed both in their entirety and as subgroups that showed robust response to the lumbar tap test. The volume of CSF removed was treated as both a continuous variable and a discrete variable. Statistical tests were repeated with log-normalized volumes. RESULTS: This study found no evidence of a relationship between the volume of CSF removed during the lumbar tap test and subsequent gait test performance in the patient population (Pearson coefficient r = 0.049-0.129). Log normalization of the volume of CSF removed and controlling for age and sex failed to yield a significant relationship. Subgroup analyses focusing on patients who showed greater than 20% improvement in any of the gait end points or who were deemed sufficiently responsive clinically to warrant surgery also yielded no significant relationships between the volume of CSF removed and gait outcomes, but there were preliminary findings that patients who underwent tap with larger-gauge needles had better postprocedure ambulation among patients who showed greater than 20% improvement in immediate time score (P = .04, n = 62). CONCLUSIONS: We found no evidence to support that a higher volume of CSF removal impacts gait testing, suggesting that a high volume of CSF removal may not be necessary in a diagnostic lumbar tap test.

Postoperative Imaging Findings following Sigmoid Sinus Wall Reconstruction for Pulse Synchronous Tinnitus.

BACKGROUND AND PURPOSE: Transmastoid sigmoid sinus wall reconstruction is a surgical technique increasingly used for the treatment of pulsatile tinnitus arising from sigmoid sinus wall anomalies. The imaging appearance of the temporal bone following this procedure has not been well-characterized. The purpose of this study was to evaluate the postoperative imaging appearance in a group of patients who underwent this procedure. MATERIALS AND METHODS: The medical records of 40 consecutive patients who underwent transmastoid sigmoid sinus wall reconstruction were reviewed. Thirteen of 40 patients underwent postoperative imaging. Nineteen CT and 7 MR imaging examinations were assessed for the characteristics of the materials used for reconstruction, the impact of these on the adjacent sigmoid sinus, and complications. RESULTS: Tinnitus resolved in 38 of 40 patients. Nine patients were imaged postoperatively for suspected complications, including dural sinus thrombosis, facial swelling, and wound drainage. Two patients underwent imaging for persistent tinnitus, and 2, for development of tinnitus on the side contralateral to the side of surgery. The materials used for reconstruction (NeuroAlloderm, HydroSet, bone pate) demonstrated characteristic imaging appearances and could be consistently identified. In 5 of 13 patients, there was extrinsic compression of the sigmoid sinus by graft material. Dural sinus thrombosis occurred in 2 patients. CONCLUSIONS: The imaging findings following sigmoid sinus wall repair are characteristic. Graft materials may result in extrinsic compression of the sigmoid sinus, and this finding may be confused with dural venous thrombosis. Awareness of the imaging characteristics of the graft materials used enables this differentiation.

1-Methyl-4-phenylpyridinium affects fast axonal transport by activation of caspase and protein kinase C.

Parkinson's disease (PD), a late-onset condition characterized by dysfunction and loss of dopaminergic neurons in the substantia nigra, has both sporadic and neurotoxic forms. Neurotoxins such as 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and its metabolite 1-methyl-4-phenylpyridinium (MPP+) induce PD symptoms and recapitulate major pathological hallmarks of PD in human and animal models. Both sporadic and MPP+-induced forms of PD proceed through a "dying-back" pattern of neuronal degeneration in affected neurons, characterized by early loss of synaptic terminals and axonopathy. However, axonal and synaptic-specific effects of MPP+ are poorly understood. Using isolated squid axoplasm, we show that MPP+ produces significant alterations in fast axonal transport (FAT) through activation of a caspase and a previously undescribed protein kinase C (PKCdelta) isoform. Specifically, MPP+ increased cytoplasmic dynein-dependent retrograde FAT and reduced kinesin-1-mediated anterograde FAT. Significantly, MPP+ effects were independent of both nuclear activities and ATP production. Consistent with its effects on FAT, MPP+ injection in presynaptic domains led to a dramatic reduction in the number of membranous profiles. Changes in availability of synaptic and neurotrophin-signaling components represent axonal and synaptic-specific effects of MPP+ that would produce a dying-back pathology. Our results identify a critical neuronal process affected by MPP+ and suggest that alterations in vesicle trafficking represent a primary event in PD pathogenesis. We propose that PD and other neurodegenerative diseases exhibiting dying-back neuropathology represent a previously undescribed category of neurological diseases characterized by dysfunction of vesicle transport and associated with the loss of synaptic function.

[Use of GnRH antagonists (cetrorelix) in assisted reproduction: first report in Mexican literature]. / Uso de antagonistas de GnRH (Cetrorelix) en reproducción asistida: primer informe en la literatura mexicana.

The use of GnRH antagonists in assisted reproduction techniques (ARTs) has been shown to be effective in blocking the luteinizing hormone (LH), without a repercussion on ovaric response. The present study reports the use of a GnRH antagonist (cetrorelix) 0.25 mg/d s.c. in patients stimulated with recombinant FSH (rFSH) for IVF/ICSI. 44 patients with mean age of 33.3 years were included in this study, four patients were receptors for oocyte donation program and another patients was receptor for frozen embryos. Controlled ovarian stimulation was carried out with rFSH, starting on day 3 of menstrual cycle. The total mean dose used was 3.570 +/- 1.102 UI for each patient. The LH serum concentrations were monitored during ovaric stimulation, in two patients a premature LH surge (> 10 UI/L) was detected. The oocytes were collected 36 hours after hCG administration, the mean preovulatory oestradiol was 4.006 +/- 2.418 pg/mL. The mean total oocytes retrieved was 10.8 +/- 7.4 per patient, the fertilization rate was 58.3%, in only three patients fertilization was failed. No difference was observed in oocyte retrieval, fertilization rate, implantation rate between both groups (GnRH antagonists versus GnRH agonists). The embryo transfer was realized on day 3, and only two patients was on blastocyst stage. In 17 of 41 patients with successful transfer, pregnancy was achieved in the group with antagonists, and 8 of 20 patients in the group with agonists. In conclusion Cetrorelix prevents adequately premature LH surges and allows an effective ovaric response in controlled stimulation in IVF cycles, except in patients in oocyte donation programs who require higher cetrorelix doses.

Uso de antagonistas de GnRH (Cetrorelix) en reproducción asistida: primer informe en la literatura mexicana / Use of GnRH antagonists (cetrorelix) in assisted reproduction: first report in Mexican literature

The use of GnRH antagonists in assisted reproduction techniques (ARTs) has been shown to be effective in blocking the luteinizing hormone (LH), without a repercussion on ovaric response. The present study reports the use of a GnRH antagonist (cetrorelix) 0.25 mg/d s.c. in patients stimulated with recombinant FSH (rFSH) for IVF/ICSI. 44 patients with mean age of 33.3 years were included in this study, four patients were receptors for oocyte donation program and another patients was receptor for frozen embryos. Controlled ovarian stimulation was carried out with rFSH, starting on day 3 of menstrual cycle. The total mean dose used was 3.570 +/- 1.102 UI for each patient. The LH serum concentrations were monitored during ovaric stimulation, in two patients a premature LH surge (> 10 UI/L) was detected. The oocytes were collected 36 hours after hCG administration, the mean preovulatory oestradiol was 4.006 +/- 2.418 pg/mL. The mean total oocytes retrieved was 10.8 +/- 7.4 per patient, the fertilization rate was 58.3, in only three patients fertilization was failed. No difference was observed in oocyte retrieval, fertilization rate, implantation rate between both groups (GnRH antagonists versus GnRH agonists). The embryo transfer was realized on day 3, and only two patients was on blastocyst stage. In 17 of 41 patients with successful transfer, pregnancy was achieved in the group with antagonists, and 8 of 20 patients in the group with agonists. In conclusion Cetrorelix prevents adequately premature LH surges and allows an effective ovaric response in controlled stimulation in IVF cycles, except in patients in oocyte donation programs who require higher cetrorelix doses.