Biological and clinical aspects in laser hair removal.

INTRODUCTION: In the past century, unwanted hair has been traditionally treated with multitudes of techniques that were found to be slow, tedious, painful, impractical, and resulted in poor long-term efficacy. Consequently, there has been a public demand for a novel, rapid, reliable, safe, and affordable hair removal technique. In the last decade, laser and light-based technology for hair removal became one of the fastest growing procedures in modern cosmetic dermatology. OBJECTIVE: To discuss the latest scientific and clinical issues in the field of photoepilation as evolved in the past decade: hair biology, laser physics and skin optics, technology and clinical experience. RESULTS: From substantial clinical experience, it becomes apparent that in the ideal subject with fair skin and dark hair, a single treatment can reduce hair by 10-40%; three treatments by 30-70%; and repeated treatments by as much as 90%. These results persist for as long as 12 months. Diffuse and perifollicular cutaneous erythema and pigmentary changes are the most common adverse side effects. Most complications are generally temporary. CONCLUSIONS: Photoepilation, when properly used, offers clear advantages when compared with older, traditional techniques. Although an ever-increasing number of published studies have confirmed the safety and short and long-term efficacy of photoepilation, the technology still has limits and risks.

Harvesting in a resource dependent age structured Leslie type population model.

We analyse the effect of harvesting in a resource dependent age structured population model, deriving the conditions for the existence of a stable steady state as a function of fertility coefficients, harvesting mortality and carrying capacity of the resources. Under the effect of proportional harvest, we give a sufficient condition for a population to extinguish, and we show that the magnitude of proportional harvest depends on the resources available to the population. We show that the harvesting yield can be periodic, quasi-periodic or chaotic, depending on the dynamics of the harvested population. For populations with large fertility numbers, small harvesting mortality leads to abrupt extinction, but larger harvesting mortality leads to controlled population numbers by avoiding over consumption of resources. Harvesting can be a strategy in order to stabilise periodic or quasi-periodic oscillations in the number of individuals of a population.

Intravitreal injection of tissue plasminogen activator for central retinal vein occlusion.

PURPOSE: This pilot study evaluated the feasibility of intravitreal injections of tissue plasminogen activator (tPA) in eyes with central retinal vein occlusion (CRVO). METHODS: Between August 1997 and October 2000, 9 eyes with CRVO were treated with intravitreal injection of tPA, 100 micrograms (50 micrograms/0.1 mL), and paracentesis. After the injection, each patient was placed at strict bed rest in the supine position for 6 hours. Each patient was administered one baby aspirin daily. Best corrected visual acuity with Light House charts was obtained at each visit. A change of 3 or more lines of vision from pretreatment levels at 6 months' follow-up or a change in one level (i.e., counting fingers to hand motions) was deemed significant. RESULTS: All patients were followed up for at least 6 months. Four of 9 eyes (44%) showed 3 or more lines improvement at 6 months. In this group, the average improvement was 7 lines. Two eyes showed 6 or more lines loss of vision at 6 months. Four eyes showed dramatic improvement in visual acuity within 1 month of injection. There were no adverse effects related to treatment. Three eyes subsequently developed retinal or anterior-segment neovascularization requiring panretinal photocoagulation; all were graded as ischemic CRVO on fluorescein angiography at baseline. CONCLUSION: Intravitreal tPA can be injected safely and easily. Local injection of tPA should spare the patient the serious systemic risks of intravenous tPA administration, such as stroke. Given the morbidity of CRVO, further investigation with this therapy to establish both efficacy and safety seems warranted.

Dark skin tissue reaction in laser assisted hair removal with a long-pulse ruby laser.

BACKGROUND: Photo-epilation has become an accepted modality for the removal of unwanted hair. However, adverse effects may occur in darker skin patients. Treatment with the ruby laser is generally advised for skin types I-III. Treatment of over 3000 patients (skin types I-III) in our clinic has resulted in a minimal percentage (approximately 3%) of adverse effects. Increasing pulse duration should allow the epidermis to cool and thus minimize thermal damage so that treatment can be extended to dark skin patients. OBJECTIVES: The purpose of our study was to compare tissue reaction in dark skin patients (skin type IV) after treatment with a long-pulse (20 msec) ruby laser and compare the reaction with a 1 msec ruby laser treatment. RESULTS: Hair removal efficacy was determined to be similar with both pulse durations, but tissue reaction was more severe, including eschar and hypopigmentation, following treatment of dark skin patients with the 1 msec protocol. Increasing the pulse duration to 20 msec appears to result in safe and efficacious ruby laser treatment even for darker skinned patients.

The effect of propranolol versus placebo on resident surgical performance.

PURPOSE: To determine whether propranolol can decrease surgical tremor and anxiety in residents performing ocular microsurgery without impairing patient or physician safety. METHODS: In this randomized, double-masked, crossover study, 5 third-year ophthalmology residents ingested a capsule containing either propranolol, 40 mg, or placebo 1 hour prior to performing ophthalmic microsurgery. All residents were healthy men under age 30 years. Prior to commencement of the study, all participants had successfully been administered a test dose of propranolol without side effects. The study took place over a 10-week period. At the conclusion of each case, both the resident and attending surgeon observer independently completed a form grading, on a sliding scale: (1) amount of overall tremor; (2) amount of tremor during placement of the first 3 sutures after lens or nucleus extraction; (3) anticipated difficulty of the case; (4) actual difficulty with the case; and (5) anxiety (surgeon only). In addition, the type of procedure performed, complications encountered, and surgeon side effects were recorded. The data were analyzed with a 2-way analysis of variance for unbalanced data. RESULTS: A total of 73 surgical cases were performed; the surgeons were administered propranolol for 40 cases and placebo for 33. As judged by the resident surgeon, there was a highly significant effect of propranolol in decreasing anxiety (P = .0058), reducing surgical tremor overall (P < .0001), and reducing tremor while placing the first 3 sutures following lens extraction (P < .0001). There was no treatment-by-surgeon interaction for any of the measures. Complications and difficulty of the case, as judged by both the resident and attending surgeons, were not significantly different in the propranolol versus placebo groups (P > .05). There were no side effects reported or observed in any of the surgeons. CONCLUSIONS: Propranolol, 40 mg, administered 1 hour prior to surgery, significantly decreases tremor and anxiety in the surgeon without untoward effects to the surgeon and the patient. However, it is unknown whether decreased tremor and anxiety improved surgical outcome.

Laser-assisted hair removal by selective photothermolysis. Preliminary results.

BACKGROUND: Laser-assisted hair removal with the long pulsed ruby laser is a promising new technique based on selectively targeting melanin in hair follicles. OBJECTIVE: The purpose of this study was to evaluate the efficacy and safety of the long pulsed ruby laser (EpiTouch) for hair removal. METHODS: The Epitouch laser was used for hair removal of the arms of 20 patients. The areas were evaluated immediately post-treatment, and at 1, 4, 8, and 12 weeks, for efficacy and complications. RESULTS: Postoperative results showed 40-80% regrowth after 12 weeks. CONCLUSION: Selective melanin-based photothermolysis with a free running pulsed ruby laser seems to be a promising, noninvasive technique for long-term hair removal. More than one treatment is necessary since only anagen hair will be affected.

Visual field loss following vitreous surgery.

OBJECTIVE: To assess possible causes of visual field loss following vitreous surgery. DESIGN: Charts of 8 patients prospectively identified, who developed visual field loss following vitreous surgery, were reviewed to characterize this newly recognized syndrome and assess possible causes. RESULTS: Two patients had preexisting chronic open-angle glaucoma and 1 had ocular hypertension. Indications for surgery included 4 eyes with macular holes, 1 eye with epiretinal membrane, 2 eyes with rhegmatogenous retinal detachment, and 1 eye with retinal detachment and giant retinal tear. All patients received retrobulbar anesthesia. Seven of 8 patients had fluid/gas exchange with installation of long-acting bubbles. In 1 patient with a macular hole, a small hemorrhage was noted along a vessel coming off the nerve superotemporally while attempting to engage the posterior cortical vitreous intraoperatively. This patient developed an inferior visual field defect. No intraocular pressure (IOP) measurements greater than 26 mm Hg were recorded in any eye perioperatively. Visual field defects included 4 eyes with inferotemporal defects, 2 eyes with inferior altitudinal defects, 1 eye with a cecocentral scotoma, and 1 eye with a superonasal defect. Only 1 patient had worsened visual acuity. A relative afferent pupillary defect was observed in 4 eyes and disc pallor in 5 eyes. CONCLUSIONS: Central or peripheral visual field loss can now be recognized as a possible complication of vitreous surgery. In some cases, a relative afferent pupillary defect and optic disc pallor are present, suggesting that the optic nerve is the site of injury. Possible mechanisms include ischemia due to elevated IOP or fluctuations in IOP, optic nerve damage from retrobulbar injection, direct intraoperative mechanical trauma to the optic nerve, indirect injury from vigorous suction near the optic nerve leading to shearing of peripapillary axons or vessels, or a combination of these. Certain optic nerves may be more susceptible to injury because of preexisting compromise from glaucoma or vascular disease.

Thrombolytic therapy for central retinal vein occlusion: results of a pilot study.

OBJECTIVE: To evaluate the feasibility of conducting a randomized, controlled trial of thrombolytic therapy for central retinal vein occlusion (CRVO) using tissue plasminogen activator (TPA); to establish relative efficacy and safety of various dosing regimens. DESIGN AND PATIENTS: Ninety-six patients with CRVO were treated with TPA between May 1986 and December 1992. Prior to patient enrollment, a standardized, detailed protocol was developed for evaluation and treatment of all patients. This included standard protocols for determining eligibility, reporting complications, performing photography and electroretinography, and measuring visual acuity. MAIN OUTCOME MEASURES: Best corrected visual acuity at 6 months, systemic and ophthalmic treatment complications. RESULTS: At 6 months' follow-up, 42% (n = 89) of eyes gained three or more lines of vision from pretreatment levels (average gain, 5.1 lines), 37% remained stable, and 21% lost three or more lines. Of eyes with 20/100 or worse pretreatment vision (n = 32), 59% gained three or more lines vision (average gain, 6.4 lines), 31% remained stable, and 9% lost three or more lines. One patient suffered a fatal stroke. Three patients developed intraocular bleeding during TPA administration. CONCLUSION: Thromobolytic therapy with TPA appears to be a promising, albeit risky, new treatment; conclusive evaluation of safety and efficacy awaits a multicenter, randomized, clinical trial; feasibility of such a trial has been established by this study.

Endogenous Fusarium endophthalmitis in a patient with acute lymphocytic leukemia.

Endogenous fungal endophalmitis is an uncommon complication of systemic mycosis. Only a few cases involving Fusarium have been reported, most with unfavorable visual outcomes. We examined a 31-year-old woman with acute lymphocytic leukemia who developed sudden visual loss in her right eye. A dense, white placoid infiltrate was present in the right macula extending into the vitreous. An iris nodule and hypopyon were present in the left eye. A vitreous aspirate of the right eye was positive for Fusarium species. The patient progressively lost vision despite amphotericin B and 5-fluorocytosine therapy. She died from bronchopneumonia, fungemia, and multisystem failure. Histopathologic study disclosed a panophthalmitis with Fusarium organisms invading all the ocular coats in the right eye. Leukemic infiltrates were present in the left iris, anterior chamber, and trabecular meshwork. The ocular destructiveness of Fusarium may be caused by marked mycotic vascular invasion and occlusion with consequent infarction and necrosis of ocular tissues.

Pathogenesis of urinary tract infection--experimental studies of vaginal resistance to colonization.

The review summarizes studies of vaginal colonization resistance against Escherichia coli in a primate model. The genital flora surrounding the urethral orifice exerts a strong colonization resistance. Amoxicillin profoundly disturbs the normal vaginal microflora, reduces its adherence to vaginal epithelial cells in vivo and promotes a persistent vaginal E. coli colonization. Certain cephalosporins may have a similar effect. The induced ecological changes mimic those seen in patients with recurrent urinary tract infections (UTI). Amoxicillin also promotes the spread of E. coli from rectum to vagina, which may be of clinical significance. Trimethoprim and nitrofurantoin do not have these effects. The natural colonization resistance could not clearly be correlated with the presence of lactobacilli, which were only transiently reduced by amoxicillin. The colonization resistance against E. coli could only partly be restored by vaginal instillation of lactobacilli, but was fully restored by flushing of the whole vaginal flora from a healthy monkey. Clinical observations suggest that accumulation of E. coli around the urethral orifice increases the risk of UTI. We conclude that antibiotics and other compounds that interfere with the normal genital flora may increase the risk of UTI. This should influence the choice of antibiotics in the treatment of UTI.

Optic nerve decompression surgery improves visual function in patients with pseudotumor cerebri.

Papilledema from pseudotumor cerebri can cause severe loss of visual acuity and visual field. We performed optic nerve decompression surgery on 17 patients with pseudotumor cerebri who, despite maximum conventional therapy, developed progressive loss of visual acuity and/or visual field. Postoperatively, visual acuity improved or stabilized in 33 of 34 eyes (97%). Visual fields improved in 20 of 21 eyes that underwent surgery. Optic nerve decompression surgery relieves local cerebrospinal fluid pressure on the optic nerve. Progressive loss of visual function associated with pseudotumor cerebri can be reversed or stabilized with optic nerve sheath decompression surgery.

The effect of amoxycillin on vaginal colonization resistance and normal vaginal flora in monkeys.

Previous studies have shown that vaginal colonization resistance in monkeys can be eliminated by amoxycillin and restored by flushing vaginal flora from a healthy monkey into the vagina of a monkey colonized with Escherichia coli. The hypothesis that the effect of amoxycillin resulted from elimination of parts of the normal flora was tested in the present study. Nine monkeys were flushed vaginally with amoxycillin daily for six days. The number of anaerobic bacteria decreased during amoxycillin administration, as did the number of species isolated. The most obvious effects were observed among the genera Bacteroides and Peptostreptococcus, while Lactobacillus spp. were less affected. Restoration of the flora after amoxycillin administration was slow in most of the monkeys. During amoxycillin administration, all monkeys became colonized spontaneously with E. coli. This was not, however, associated with increased adherence in vitro. The colonization persisted throughout the study period (29 days). It was concluded that amoxycillin disturbs vaginal colonization resistance by eliminating at least part of the normal vaginal flora, thereby promoting periurethral colonization with enterobacteria.

Lack of effect of trimethoprim and nitrofurantoin on colonization resistance in the vagina of monkeys.

The effects of trimethoprim and nitrofurantoin, two antibiotics often used for treatment and long-term prophylaxis of urinary tract infections, on colonization resistance in the vagina of monkeys were investigated. Female monkeys were flushed intravaginally with one of the antibiotics or buffered saline or amoxicillin (controls) for six days. During or after this antibiotic administration a pyelonephritogenic Escherichia coli, strain DS17, was flushed into the vagina. A persistent colonization was obtained in two of eight trimethoprim experiments and a transient colonization in one trimethoprim and two of seven nitrofurantoin experiments. These results did not differ significantly from those of the buffer control experiments. Neither the number of anaerobic bacteria nor the composition of the anaerobic microflora was much affected by these antibiotic agents, while amoxicillin both reduced the number of anaerobic bacteria and promoted E. coli colonization. We conclude that trimethoprim and nitrofurantoin exert a limited effect on the microecology and the colonization resistance in the vagina. From an ecological aspect both drugs seem to be good choices for treatment and prophylaxis of urinary tract infections.

Modified optic nerve decompression in patients with functioning lumboperitoneal shunts and progressive visual loss.

Chronic papilledema from pseudotumor cerebri can cause progressive visual loss despite functioning lumboperitoneal shunts. The authors performed modified optic nerve sheath decompression in 12 patients (16 operations) with functioning lumboperitoneal shunts and progressive visual loss. All of the patients demonstrated improvement in visual function. Optic nerve sheath decompression allows release of localized cerebrospinal fluid (CSF) pressure. By performing optic nerve sheath decompression, progressive visual loss secondary to chronic papilledema can be halted and reversed.

The effect of age and initial visual acuity on the systemic and visual prognosis of central retinal vein occlusion.

Papillophlebitis is the term that is often used to describe a central retinal vein occlusion with preserved visual acuity in a young, healthy patient. Among 194 patients with a diagnosis of central retinal vein occlusion (CRVO), 19 patients were identified who were under 50 years of age and who had visual acuity of 6/12 or better in the affected eye. These patients retained good vision in the affected eye during the course of the disorder with 17 eyes returning to 6/6. All of these patients remained healthy over a mean follow-up period of about four years. This group of patients was compared to a second group of 28 patients who also were under 50 years of age, but who had initial visual acuity in the affected eye less than 6/12. These patients had a variable visual outcome. In addition, they had a higher prevalence of systemic hypertension over the follow-up period than did a group of age-matched control subjects. An additional comparison was made to a group of 26 patients with visual acuity of 6/12 or better in the affected eye but who were over 50 years of age. Forty-six per cent of these patients had final visual acuity less than 6/12, and they had a higher prevalence of systemic vascular disease than did a group of age-matched control subjects.