A Comparative Study of the Percutaneous versus Intraoral Technique for Mental Nerve Block

Objective: Mental nerve block is frequently used to aid repair of facial lacerations; both percutaneous and intraoral approaches to blocking this nerve are used, but have never been compared. The authors compared the two techniques for pain of administration and effectiveness of anesthesia. Methods: A prospective, randomized, single-blind, crossover study was conducted using ten healthy volunteers aged 22 to 33 years. Patients having prior experience with mental nerve blocks, lidocaine allergy, active oral/facial infection, or previous facial fractures were excluded. Bilateral mental nerve blocks were done using intraoral technique on one side and percutaneous technique on the other. Both techniques were used by the same investigator and were carried out with 27-gauge needles and 2.5 mL of 2% buffered lidocaine at room temperature injected over 20 seconds. The oral mucosa was topically anesthetized with viscous lidocaine for 1 minute prior to intraoral injection. The orders of the blocks and sides of the face anesthetized were randomized. Subjective and objective pain (visual-analog scale), efficacy (anesthesia of lower lip), time to onset, and duration of anesthesia were evaluated. Results: The intraoral technique was subjectively less painful than the percutaneous approach in nine of ten subjects (p = 0.02). Scores on the visual-analog pain scale were significantly lower for the intraoral technique (p = 0.03). Intraoral injection produced lower-lip anesthesia in 10/10 subjects versus 7/10 for percutaneous (p = 0.25). Times to onset (approximately 1–2 minutes) and durations of anesthesia (approximately one hour) were similar for the two techniques. Conclusion: The intraoral approach to the mental nerve block with adjunctive topical anesthesia was subjectively and objectively less painful than the percutaneous approach without adjunctive anesthesia. While the intraoral approach had a greater efficacy of lower-lip anesthesia and a longer duration of action, these differences were not statistically significant.     

Tolerance-like attenuation to contingent and noncontingent cocaine-induced elevation of extracellular dopamine in the ventral striatum following 7 days of withdrawal from chronic treatment

Time-dependent changes in mesolimbic dopamine (DA) function are believed to play a role in behavioral sensitization and drug craving experienced during withdrawal from chronic cocaine administration. The present study utilized intravenous (IV) cocaine self-administration coupled with intracranial microdialysis in rats to investigate time dependent changes during withdrawal from chronic cocaine exposure. Following 2 weeks of IV cocaine self-administration, rats were allowed contingent access to cocaine at 1 and 7 days of withdrawal while extracellular levels of DA were measured from the ventral striatum. A second group of animals received yoked, noncontingent cocaine for 2 weeks and were then administered noncontingent cocaine on days 1 and 7 of withdrawal. In addition, a third group of animals received 2 weeks of yoked saline followed by noncontingent cocaine 1 day after withdrawal. There were no significant differences between groups for the overall cocaine dosage or temporal pattern of infusions on days 1 and 7 of withdrawal. Basal extracellular DA concentrations did not differ between any treatment groups at either withdrawal time. Extracellular DA levels were increased throughout the session on both days; however, the increases at day 7 were significantly less than day 1 for both contingent and noncontingent conditions. DA overflow on day 1 did not differ between animals receiving chronic yoked cocaine or saline. These results suggest that tolerance-like attenuation to the DA-elevating effects of cocaine is not apparent early in withdrawal, but does develop by later time points. DA release in the ventral striatum may not be directly related to cocaine self-administration following withdrawal, since DA levels were attenuated after 7 days of withdrawal while responding for cocaine was unaltered.     

Decreased relative efficacy of the ketogenic diet for children with surgically approachable epilepsy.

PURPOSE: In children with intractable, surgically approachable epilepsy, the ketogenic diet is often perceived as less efficacious than surgery. METHODS: A retrospective chart review was performed of 554 children started on the ketogenic diet since 1994. Forty-five children were identified as surgical candidates, with at least 2 focal routine EEGs, ictal video-EEG, and corresponding focal neuroimaging findings, of whom 24 eventually had resective surgery and were followed subsequently. A comparison cohort group was also created of 45 children matched for age and seizure frequency that received the diet but were not surgical candidates (multifocal or generalized seizures). RESULTS: Of the 24 children who received both dietary and surgical therapies, there was a higher likelihood after 6 months of both >90% seizure reduction (71% versus 17%) and seizure freedom (63% versus 0%) following surgery, both p < 0.0001. Similarly, the 45 cohort children who were not surgical candidates were more likely to be seizure-free (29% versus 13%, p = 0.041) and remained on the diet for shorter duration (10 months versus 18 months, p = 0.035) compared to the surgical group. CONCLUSION: Children with surgically approachable epilepsy do respond to the diet, but are more likely to be seizure-free following surgery.     

Buflomedil. A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic efficacy in peripheral and cerebral vascular diseases

Buflomedil hydrochloride is a vasoactive drug with a variety of pharmacodynamic properties. Importantly, it seems to improve nutritional blood flow in ischaemic tissue of patients with peripheral and/or cerebral vascular disease by a combination of pharmacological effects: inhibition of alpha-adrenoceptors, inhibition of platelet aggregation, improved erythrocyte deformability, nonspecific and weak calcium antagonistic effects, and oxygen sparing activity. Therapeutic trials with buflomedil in patients with peripheral vascular diseases have shown that it increases walking distances in those with intermittent claudication and heals trophic lesions and reduces rest pain in many patients with more severe vasculopathies. In open clinical trials a good to very good clinical response was achieved in 57 to 87% of those treated. In comparative studies buflomedil 600 mg/day orally was shown to be significantly superior to placebo and comparable in efficacy to pentoxifylline (oxpentifylline) and naftidrofuryl. In patients with symptoms presumed to be due to cerebrovascular insufficiencies and elderly patients with senile dementia, buflomedil 450 to 600 mg/day alleviated symptoms associated with impairment of cognitive and psychometric function and was significantly superior to placebo and slightly more effective than drugs such as cinnarizine, flunarizine and co-dergocrine mesylate. Overall, buflomedil at dosages of up to 600 mg/day has been very well tolerated and discontinuation of therapy has rarely been necessary. Thus, buflomedil would seem to be a useful adjunct to conservative treatment in patients with mild-to-moderate peripheral vascular disease and/or cerebrovascular insufficiency, and well worth a try in patients with more severe peripheral disease unable to undergo surgery. However, a few well-designed long term studies are needed to fully define its overall place in therapy.     

Thrombosis of the inferior vena cava by seminoma

We report a case of metastatic seminoma that caused thrombosis and obstruction of the inferior vena cava. The pathogenesis of this rare clinical entity is discussed. The diagnostic studies for detection of vena caval thrombosis and clinical management strategies are reviewed.