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David Lee

Publications and source records attributed to David Lee.

At least 91 records · Page 5Linked to original sources

Epiretinal membrane formation is a late manifestation of shaken baby syndrome.

Shaken baby syndrome is a constellation of injuries resulting from the intentional shaking type movement of a child who is usually younger than 3-years-old. This rapid acceleration-deceleration movement of the head is responsible for lesions attributed to shearing forces placed on the vitreoretinal structures and meningeal vessels across the dura. The ophthalmic findings include intraocular hemorrhages, perimacular retinal folds, and peripheral retinoschisis in the presence of intracranial injuries such as subdural hematomas without obvious external signs of head trauma. We describe a case of late development of an epiretinal membrane in a child with a history of shaken baby syndrome and propose a differential diagnosis list for epiretinal membrane formation in the pediatric age group.

Epiretinal Membrane↗

Transjugular liver biopsy effecting changes in clinical management.

Although transjugular liver biopsies are frequently performed in patients with impaired blood coagulation, their impact on effecting changes in clinical management has not been assessed. We reviewed our experience with 43 consecutive transjugular liver biopsies performed over 3 years (1998-2000) at Westmead Hospital, Sydney, Australia. The technical success, procedural complication rates and subsequent management of these patients were ascertained from the medical case records. Forty-two (28 men) patients were studied. The indications for liver biopsy were as follows: assessment of hepatitis/cirrhosis status (n = 21), evaluation of liver dysfunction following bone marrow transplantation (n = 19) and miscellaneous (n = 2). All liver biopsies were performed with a Cook 20-G transjugular cutting needle device. Adequate histological samples were obtained in 42 (98%) of the 43 biopsies performed. The pre-biopsy diagnoses were confirmed by histology in 28 cases (65%). A change in clinical diagnosis was observed in 12 (28%) patients, and there were changes to subsequent management in all 12 patients. Four patients developed procedural complications, including small neck haematomas in two patients and a self-limiting biliary fistula in one. The only major complication was an extracapsular bleed from a hepatic laceration. This patient required emergency surgery but recovered. Transjugular liver biopsies can be effectively and safely performed in high-risk patients with impaired coagulation. They aid accurate histological appraisal of liver dysfunction in these patients and influence clinical decision-making.

Adult↗

Ocular hypotensive efficacy of bimatoprost when used as a replacement for latanoprost in the treatment of glaucoma and ocular hypertension.

PURPOSE: To evaluate the clinical effectiveness of bimatoprost (Lumigan, Allergan, Inc.) when used as a replacement for latanoprost (Xalatan, Pharmacia) in the treatment of glaucoma and ocular hypertension. METHODS: This was a community-based, two-month, open-label, multicenter, trial. Patients with glaucoma or ocular hypertension who needed additional IOP lowering or who were intolerant of other glaucoma medications were placed on bimatoprost therapy (alone or in combination with other drugs at the physician's discretion). RESULTS: This first report of the data from this study focuses on those patients for whom the physician chose to replace latanoprost therapy with bimatoprost therapy (n = 1283). After 2 months of bimatoprost therapy, the mean decrease in IOP was 3.4 mm Hg and many more patients had achieved low target pressures. The percentage of patients achieving a target pressure of < or =18 mm Hg doubled from 33% to 66% (P <.001). The percentage of patients achieving target pressures of < or =15 mm Hg and < or =14 mm Hg was approximately 3 to 4 times greater at the end of the study than the beginning; increasing from 11% to 36% and from 6% to 26%, respectively (P <.001). A subgroup analysis showed comparable improvements in IOP-control regardless of the previous treatment regimen or whether bimatoprost was used alone or in combination with other medications. The most commonly reported adverse event was conjunctival hyperemia (3.7%; 47/1283). CONCLUSION: Bimatoprost therapy is well-tolerated and helps many more patients reach low target pressures when used as a replacement for latanoprost in a variety of treatment regimens.

Amides↗

Successful transfer of open surgical skills to a laparoscopic environment using a robotic interface: initial experience with laparoscopic radical prostatectomy.

PURPOSE: For a skilled laparoscopic surgeon the learning curve for achieving proficiency with laparoscopic radical prostatectomy (LRP) is estimated at 40 to 60 cases. For the laparoscopically naïve surgeon the curve is estimated at 80 to 100 cases. The development of a robotic interface might significantly shorten the LRP learning curve for an experienced open yet naïve laparoscopic surgeon. To our knowledge we report the initial experience with robot assisted LRP of a surgeon without laparoscopic experience. MATERIALS AND METHODS: Following a 1-day da Vinci (Intuitive Surgical, Mountain View, California) robotic laparoscopic training course and 2 cadaveric robotic LRPs an experienced oncologist (TEA) without laparoscopic experience performed 45 robotic LRPs. RESULTS: All procedures were successfully completed laparoscopically with no rectal injuries or transfusions. The learning curve to 4-hour proficiency was 12 patients and mean operating time subsequently was 3.45 hours (range 2.5 to 5.1). Mean blood loss was 145 cc (range 25 to 350), the mean postoperative day 1 decrease in hemoglobin was 2.6 mg/dl (range 1.9% to 5.1) and mean hospital stay was 36 hours (range 18 to 168). Mean Gleason score was 6.8, mean prostate volume was 50.5 gm (range 12.5 to 163) and the margin positive rate was 35.5%. Four patients (8.8%) had a total of 6 complications, which were managed conservatively. Catheterization time was 7 days (range 7 to 42). Continence (0 pads) was 33% at 1 week, 63% at 1 month and 81% at 3 months. CONCLUSIONS: A laparoscopically naïve yet experienced open surgeon successfully transferred open surgical skills to a laparoscopic environment in 8 to 12 cases using a robotic interface. This outcome is comparable to the reported experience of skilled laparoscopic surgeons after more than 100 LRPs.

Aged↗

Evaluation of synchronous twin pulse technique for shock wave lithotripsy: determination of optimal parameters for in vitro stone fragmentation.

PURPOSE: The Twinheads extracorporeal shock wave lithotriptor (THSWL) is composed of 2 identical shock wave generators and reflectors. One reflector is under the table and the other is over the table with a variable angle between the axes of the 2 reflectors. The 2 reflectors share a common second focal point, making it possible to deliver an almost synchronous twin pulse to the targeted stone. We studied the optimal parameters for in vitro stone fragmentation. MATERIALS AND METHODS: Two types of 1 cm artificial stones were used, namely Bon(n)-stones of 3 compositions (75% calcium oxalate monohydrate [COM] plus 25% uric acid, struvite and cystine) and plaster of Paris. The parameters tested were shock wave number (100, 500 and 1,000), shock wave power (8, 11 and 14 kV) and angle between the reflector axes (67, 90 and 105 degrees). After the optimal parameters were determined we studied the disintegrative efficacy of THSWL for 3 types of human urinary calculi, including COM, calcium hydrogen phosphate (brushite) and cystine. Each stone received 1,000 twin shock waves at 14 kV with an angle of 90 degrees between the reflectors. All experiments were done using a rate of 60 twin shock waves per minute. Following lithotripsy stone fragments were processed and sized. The ratio of the weight of fragments greater than 2 mm-to-total weight of all fragments was calculated. RESULTS: Optimal stone fragmentation results for THSWL were obtained with the maximum number of shock waves (1,000) and full power (14 kV). There was no significant statistical difference in fragment size or the ratio of fragments greater than 2 mm with the use of different angles except for cystine and plaster of Paris calculi, for which the right angle was most effective. At application of the optimal parameters to human stones THSWL produced small fragment size for COM and cystine stones, while brushite stones were not fragmented to the same extent. CONCLUSIONS: The efficacy of synchronous twin pulse technology improves as the number of shock waves and power increase. A 90-degree angle between the shock wave reflectors is advantageous for certain stones (that is cystine and plaster of Paris) but it is not a factor for other stone compositions. THSWL has satisfactory disintegrative efficacy for human stones, especially COM and cysteine calculi.

Calcium Oxalate↗

Using a 401(h) account to fund retiree health benefits from your pension plan.

If a health and welfare plan covering retirees faces financial shortfalls, administrators and trustees can fund retiree health benefit payments from a related pension plan that may be in better condition. This method is legal and ethical, but it requires sophisticated accounting techniques for creating an account that provides retiree members with promised benefits while meeting statutory and regulatory requirements.

Accounting↗

Investigation of the diastereoselective cyclization of bis-sulfonyl esters.

[reaction: see text] The diastereoselective cyclization of bissulfonyl esters was investigated by varying both the size and the placement of the substituent on the tether adjoining the reacting centers. Substitution at either the alpha or beta position relative to the ester moiety gave diastereomeric ratios of (1-3):1, while gamma substitution dramatically increased the diastereomeric ratios to (6-20):1.

Journal Article↗