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David Varssano

Publications and source records attributed to David Varssano.

8 recordsLinked to original sources
PubMed2005

Alcohol- vs hypertonic saline-assisted laser-assisted subepithelial keratectomy.

OBJECTIVE: To evaluate the predictability and safety of hypertonic saline (5% sodium chloride) [correction]-assisted laser-assisted subepithelial keratectomy (HS-LASEK) vs 20% alcohol-assisted LASEK (A-LASEK). SETTING: American Laser Medical Center, Rishon Le-Zion, Israel. METHODS: Fifty-two consecutive eyes (26 patients) were randomized to HS-LASEK (30 eyes) and A-LASEK (22 eyes) groups. The patients' eyes were examined, refracted, and photographed at 1 day, 5 days, 2 weeks, and 1 month postoperatively by a masked physician. Corneal topography and confocal examination were performed before and 1 month after surgery. MAIN OUTCOME MEASURES: The predictability, accuracy, and visual recovery of HS-LASEK vs A-LASEK in the first postoperative month. RESULTS: The accuracy of HS-LASEK was similar and sometimes better than A-LASEK. Two weeks after surgery, 17 eyes (57%) in the HS-LASEK group and 10 eyes (46%) in the A-LASEK group were within +/- 0.5 diopter of the intended refractive correction (P<.05). At all time points eyes in the HS-LASEK group had better best-corrected visual acuity than eyes in the A-LASEK group, although the uncorrected visual acuity was similar. Eighteen (61%) of the HS-LASEK-treated eyes and 12 (55%) of the A-LASEK-treated eyes had an epithelial defect after surgery. The HS-LASEK-treated eyes had significantly larger epithelial defects. The resolution of the defects was faster in the HS-LASEK-treated eyes (mean +/- SD, 4.5 +/- 0.4 days vs 5.8 +/- 0.2 days, P = .002). The subepithelial scar was thicker in A-LASEK-treated eyes. CONCLUSIONS: Hypertonic saline-assisted LASEK provides good postoperative accuracy, safety, and a similar rate of complications. In view of recent evidence regarding the epithelial toxic effects of alcohol, HS-LASEK might be a better treatment alternative.

Adult↗
PubMed2005

Air transportation of corneal tissue: experience with local compared to transatlantic donor corneas.

PURPOSE: To compare the outcome of corneas obtained at the same hospital in which they were transplanted (group 1) to that of corneas obtained in the United States and grafted in Israel (group 2). METHODS: One hundred twenty-six patients undergoing corneal grafting in Israel during the years 1995 to 1998 were included in a retrospective, nonrandomized clinical trial. Group 1 included 31 procedures, and group 2 included 95. Data regarding preoperative condition, tissue characteristics, and postoperative outcome were collected from hospital charts. Statistically significant difference between groups was considered as P < 0.05. RESULTS: Follow-up time was 796 +/- 523 days for group 1 (mean +/- SD) and 815 +/- 510 days for group 2. Donor age and gender, recipient age and gender, graft size, and length of follow-up were similar. Time from preservation to transplantation was longer for group 2 (8.8 +/- 2.29 days) compared with in group 1 (3.13 +/- 2.38 days). Graft clarity was similar between groups 1 and 2 at 1 year (79% versus 71%) and at last follow-up visit (57% versus 62%). Visual acuity, intraocular pressure, and incidence of complications such as rejection (32% versus 38%), failure (35% versus 28%), secondary glaucoma (35% versus 43%), corneal ulcer (13% versus 6%), and regrafts (13% versus 7%) showed no difference between the groups. CONCLUSIONS: Air transport of corneal tissue, including loss of time due to travel and handling, did not compromise corneal transplantation success rate.

Aircraft↗
PubMed2004

Contrast sensitivity after wave front-guided LASIK.

PURPOSE: To compare the effects on contrast sensitivity of wave front-guided (WFG) versus standard LASIK. DESIGN: Prospective, nonrandomized, comparative clinical study. PARTICIPANTS: Twenty-four eyes of 13 consecutive patients (mean age, 25.2+/-8.4 years; spherical equivalent, -0.5 to -4.25 diopters [D]) treated with WFG LASIK (WaveLight-Allegretto scanning-spot laser and wave front analyzer) and 22 eyes of 12 consecutive patients (mean age, 28.4+/-9.1 years; spherical equivalent, -0.75 to -4.5 D) treated with standard LASIK (WaveLight-Allegretto scanning-spot laser). METHODS: Best-corrected contrast sensitivity was measured before and 1 month after surgery in both the WFG LASIK group and the standard LASIK group. A sine-wave contrast sensitivity test (functional acuity contrast test) was used to measure contrast sensitivity at 5 spatial frequencies (1.5, 3, 6, 12, and 18 cycles/degree). We compared the LASIK-induced changes in contrast sensitivity in each groups at each spatial frequency. MAIN OUTCOME MEASURE: The effect on contrast sensitivity of WFG LASIK versus standard LASIK. RESULTS: Uncorrected visual acuity of 20/20 or better was achieved by 72% of eyes treated with WFG LASIK and by 70% of the eyes treated with standard LASIK. One month after LASIK, 88% of the contrast sensitivity measurements improved in the WFG LASIK group, whereas in the standard LASIK group, only 40% of the contrast sensitivity measurements improved. The contrast sensitivity improvement was significantly larger in the WFG LASIK group at all spatial frequencies (P<0.05). The WFG LASIK patients had a negative correlation between the changes in contrast sensitivity and the preoperative refractive error. CONCLUSIONS: The ability of WFG LASIK to correct optical aberrations results in significantly improved contrast sensitivity compared with standard LASIK 1 month after surgery.

Adult↗
PubMed2004

Antichemical protective gear prolongs time to successful airway management: a randomized, crossover study in humans.

BACKGROUND: Airway management is the first step in resuscitation. The extraordinary conditions in mass casualty situations impose special difficulties in airway management, even for experienced caregivers. The authors evaluated whether wearing surgical attire or antichemical protective gear made any difference in anesthetists' success of airway control with either an endotracheal tube or a laryngeal mask airway. METHODS: Fifteen anesthetists with 2-5 yr of residency and wearing either full antichemical protective gear or surgical attire intubated or inserted laryngeal masks in 60 anesthetized patients. The study was performed in a prospective, randomized, crossover manner. The duration of intubation/insertion was measured from the time the device was grasped to the time a normal capnography recording was obtained. RESULTS: Endotracheal tubes were introduced significantly (P < 0.01) faster when the anesthetist wore surgical attire (31 +/- 7 vs. 54 +/- 24 s for protective gear), but the mean times necessary to successfully insert laryngeal masks were similar (44 +/- 20 s for surgical attire vs. 39 +/- 11 s for protective gear). Neither performance failure nor incidences of hypoxemia were recorded. CONCLUSIONS: This first report in humans shows to what extent anesthetists' wearing of antichemical protective gear slows the time to intubate but not to insert a laryngeal mask airway compared with wearing surgical attire. Laryngeal mask airway insertion is faster than tracheal intubation when wearing protective gear, indicating its advantage for airway management when anesthetists wear antichemical protective gear. If chances for rapid and successful tracheal intubation under such chaotic conditions are poor, laryngeal mask airway insertion is a viable choice for airway management until a proper secured airway is obtainable.

Adult↗
PubMed2004

Topographic patterns in refractive surgery candidates.

PURPOSE: To evaluate the prevalence of different topographic patterns in refractive surgery candidates and to estimate the extent of candidate rejection based on topography alone. METHODS: We performed a retrospective evaluation of videokeratographies of previously unoperated refractive surgery candidates. The defined topographic patterns of their corneas and the indices computed by the videokeratographer software were registered. The data were evaluated by SPSS/PC statistical software. RESULTS: One hundred candidate electronic topography records were evaluated. The candidates included 41 women and 59 men whose average age was 32 years (range 17.5-63.5). Their topographic patterns were: spherical (36/200 evaluated eyes), spherocylindrical (60), upper steep (32), lower steep (43), irregular astigmatism (9), decentered (3), suspected keratoconus (11), and probable keratoconus (6 eyes). Rejection from undergoing the procedure was based on topography alone in 27 of the 200 eyes. It was difficult to decide what to do with the 43 eyes with a lower steep pattern, and they were eventually rejected. Of the nine software-calculated indices, only one, "keratoconus index," could distinguish between the spherocylindrical and the lower steep patterns. CONCLUSIONS: More than one-half of corneal topographies of refractive surgery candidates did not comply with the assumed "normal" spherical or spherocylindrical patterns. The possible continuum of keratoconus-suspected keratoconus-lower steep pattern raises the question of where to draw the line between reasonable and risky when considering corneal refractive surgery.

Adolescent↗
PubMed2002

Excision of pterygium and conjunctival autograft.

BACKGROUND: Pterygium is a common disease in Israel. Different surgical techniques are used to manage it with varying degrees of success. OBJECTIVES: To evaluate the efficacy and safety of a conjunctival autograft after excision of pterygium. METHODS: Excision followed by conjunctival autograft was used to treat 40 eyes of 40 patients with pterygium. The surgical results were evaluated retrospectively. Follow-up continued for a median of 296 days (range 6-1,056); 26 cases were followed for more than 100 days (average 418 days) and comprised the study cohort. All reported procedures were performed consequentially and by one surgeon in the Tel Aviv Sourasky Medical Center, Israel between 1 June 1997 and 31 March 2000. RESULTS: There were two recurrences of pterygium (2/26, 7.7%) 2 months postoperatively. There were no major complications. Superficial comeal vessels (without concurrent fibrosis) appeared in 10 of 17 cases sutured with nylon, but none occurred in any of the seven grafts sutured with vicryl (P = 0.068). The average LogMAR-corrected visual acuity of the study group improved slightly, from 6/16.5 to 6/11 (P = 0.003). CONCLUSIONS: Excision of pterygium with a conjunctival autograft is a safe and effective operation, with no procedure-specific added surgical risks. The relatively long surgical time and microsurgical methods required to perform the procedure properly have hindered its acceptance as the mainstream approach to pterygium management. Long-term follow-up is needed for better discernment of the surgical results in Israel.

Adult↗
PubMedDate not supplied

Hospital preparedness for possible nonconventional casualties: an Israeli experience.

Since 9/11, hospitals and health authorities have been preparing medical response in case of various mass terror attacks. The experience of Tel Aviv Sourasky Medical Center in treating suicide-bombing mass casualties served, in the time leading up to the war in Iraq, as a platform for launching a preparedness program for possible attacks with biological and chemical agents of mass destruction. Adapting Quarantelli's criteria on disaster mitigation to the "microinfrastructure" of the hospital, and including human behavior experts, we attempted to foster an interactive emergency management process that would deal with contingencies stemming from the potential hazards of chemical and biological (CB) weapons. The main objective of our work was to encourage an organization-wide communication network that could effectively address the contingent hazards unique to this unprecedented situation. A stratified assessment of needs, identification of unique dangers to first responders, and assignment of team-training sessions paved the way for program development. Empowerment through leadership and resilience training was introduced to emergency team leaders of all disciplines. Focal subject matters included proactive planning, problem-solving, informal horizontal and vertical communication, and coping through stress-management techniques. The outcome of this process was manifested in an "operation and people" orientation supporting a more effective and compatible emergency management. The aim of article is to describe this process and to point toward the need for a broad-spectrum view in such circumstances. Unlike military units, the civilian hospital staff at risk, expected to deal with CB casualties, requires adequate personal consideration to enable effective functioning. Issues remain to be addressed in the future. We believe that collaboration and sharing of knowledge, information, and expertise beyond the medical realm is imperative in assisting hospitals to expedite appropriate preparedness programs.

Biological Warfare↗