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Dive into the research topics where John D. McCann is active.

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Featured researches published by John D. McCann.


American Journal of Ophthalmology | 1995

A Sensitive and Specific Polymerase Chain Reaction-Based Assay for the Diagnosis of Cytomegalovirus Retinitis

John D. McCann; Todd P. Margolis; Mariwil G. Wong; Baruch D. Kuppermann; Alan Luckie; Daniel M. Schwartz; Alexander R. Irvine; Everett Ai

PURPOSE To develop a sensitive and specific laboratory assay for the diagnosis of cytomegalovirus retinitis. METHOD We used a polymerase chain reaction-based assay for detection of cytomegalovirus DNA in vitreous samples. We attempted to detect cytomegalovirus DNA in 19 vitreous samples from patients with the acquired immunodeficiency syndrome (AIDS) who had untreated cytomegalovirus retinitis and in 40 vitreous samples from patients with AIDS who had been treated with systemic ganciclovir or foscarnet, or both. We also attempted to detect cytomegalovirus DNA in vitreous samples from 54 immunocompetent patients, including 32 with retinal detachment or macular hole, 11 with vitreous inflammation, and 11 with vitreous hemorrhage. Additionally, we attempted to detect cytomegalovirus DNA in 15 vitreous samples from patients with AIDS who had vitreoretinal inflammation not caused by cytomegalovirus. RESULTS Cytomegalovirus DNA was detected in 18 of 19 eyes with untreated cytomegalovirus retinitis. We detected cytomegalovirus DNA in 19 of 40 vitreous samples from patients with previously treated cytomegalovirus retinitis. Cytomegalovirus DNA was not detected in any of 69 patients who did not have a clinical diagnosis of cytomegalovirus retinitis. Thus, the assay had an estimated sensitivity of 95% in detecting untreated cytomegalovirus retinitis and a sensitivity of 48% in detecting cytomegalovirus retinitis that had been treated with systemic ganciclovir or foscarnet, or both. The assay did not give false-positive results in patients with vitreous hemorrhage or vitreous inflammation. Most important, the assay did not give false-positive results in AIDS patients with vitreous inflammation from causes other than cytomegalovirus retinitis. CONCLUSION We have developed a sensitive and specific diagnostic assay that will assist in the diagnosis of cytomegalovirus retinitis.


Ophthalmic Plastic and Reconstructive Surgery | 2007

Treatment of lower eyelid retraction by expansion of the lower eyelid with hyaluronic Acid gel.

Robert A. Goldberg; Seongmu Lee; Thiran Jayasundera; Angelo Tsirbas; Raymond S. Douglas; John D. McCann

Purpose: To report our preliminary experience utilizing a nonsurgical alternative in the treatment of lower eyelid retraction: expansion and reinforcement of the lower eyelid with hyaluronic acid gel. Methods: Retrospective review of patients with lower eyelid retraction treated with hyaluronic acid gel. Pretreatment, post-treatment, and follow-up photographs were digitized and overall outcomes assessed. Measurements of inferior scleral show were standardized and compared. Results: Sixty-five procedures (31 patients; 14 male; mean age 58 years, range, 33–78 years) with lower eyelid retraction of various etiologies were treated with hyaluronic acid gel. A mean change in scleral show of 1.04 mm was found when pre- and post-treatment measurements were compared. The overall mean follow-up period was 6.2 months (range, 1–12 months). During the interval from initial treatment to follow-up visit (mean 4.6 months, range, 1–12 months), the effect of the hyaluronic acid gel diminished, with a mean increase in inferior scleral show of 0.52 mm. Twelve patients underwent a second, and 6 patients underwent a third, maintenance treatment with an improvement in scleral show of 0.87 mm and 1.13 mm, respectively. Complications were minor and included swelling, redness, bruising, and tenderness at the sites of injection. Conclusions: Based on our preliminary results, hyaluronic acid gel shows promise as a treatment modality for the management of lower eyelid retraction. Long-term follow-up will better clarify the required frequency of maintenance injections, the degree of hyaluronic acid gel retention, and the position of the lower eyelid over time.


Thyroid | 2004

Primary-Gaze Diplopia in Patients with Thyroid-Related Orbitopathy Undergoing Deep Lateral Orbital Decompression with Intraconal Fat Debulking: A Retrospective Analysis of Treatment Outcome

Guy J. Ben Simon; Lillian Wang; John D. McCann; Robert A. Goldberg

Our goal was to investigate the incidence of postoperative primary gaze diplopia in patients with thyroid-related orbitopathy (TRO) undergoing deep lateral wall orbital decompression surgery with intraconal fat debulking in the Jules Stein Eye Institute over a period of 4(1/4) years. Overall 201 orbital decompression surgeries were performed in 116 patients (23 males, 93 females). All surgeries were performed by two of the authors (R.A.G. and J.D.M.) and in the noninflammatory phase of the disease. Exophthalmos decreased by an average of 3.4 +/- 2.7 mm from 23.8 +/- 3.2 mm (17-31) to 20.4 +/- 2.5 mm (14-29), p < 0.001, 95% confidence interval (CI) (3.0:3.8). 31% of patients had preoperative primary gaze diplopia and 28.4% had postoperative primary gaze diplopia. Thirty (83%) of the 36 patients with preoperative diplopia had also postoperative diplopia; 6 (16.7%) of the 36 patients had improvement in diplopia following deep lateral wall decompression. Of the 80 (69%) of patients without preoperative double vision 3 developed postoperative double vision in primary gaze (2.6% of all patients). These 3 patients were older (56 versus 46 years, p = 0.047), had more limitation in ocular movements (p = 0.017) and achieved more decrease in proptosis with surgery (6 versus 3.1 mm, p = 0.024). No complications were associated with orbital decompression. In conclusion deep lateral wall orbital decompression surgery with intraconal fat debulking is associated with a low rate (2.6%) of new-onset primary gaze diplopia. Some patients (5.2%) with preoperative diplopia actually had improvement in diplopia postoperatively. This surgery is effective in reduction of congestion and exophthalmos, and is not associated with detrimental effects on visual acuity.


Ophthalmic Plastic and Reconstructive Surgery | 1999

A novel mechanism for benign essential blepharospasm.

John D. McCann; Mike Gauthier; Ricardo Morschbacher; Robert A. Goldberg; Richard L. Anderson; Perry G. Fine; Kathleen B. Digre

PURPOSE The purpose of this study is to test the hypothesis that the photophobia of benign essential blepharospasm (BEB) is caused by sympathetically maintained pain. METHODS Nineteen patients with photophobia and BEB were enrolled in an unblinded prospective treatment trial. The intervention was blockade of the superior sympathetic ganglion with local anesthetic. Outcome measures included the patients subjective report of ocular surface dryness, foreign body sensation, and eyelid spasm. We also obtained video recordings of eyelid movements. RESULTS Of the 19 patients, 13 reported subjective improvement in BEB symptoms after cervical sympathetic blockade (CSB). Thirteen of 19 patients also had objective evidence of decreased light-induced eyelid spasm after CSB. Ocular surface disease was present in 18 of 19 patients. CONCLUSION These data support the hypothesis that in many patients with BEB there is a sympathetically maintained pain syndrome associated with external ocular disease. We speculate on a neurologic circuit that may explain these findings.


Ophthalmic Surgery Lasers & Imaging | 2009

Early Versus Late Repair of Orbital Blowout Fractures

Guy J. Ben Simon; Hasan M Syed; John D. McCann; Robert A. Goldberg

BACKGROUND AND OBJECTIVE To compare early and late surgical repair of orbital blowout floor fractures. PATIENTS AND METHODS A retrospective, comparative interventional case series reviewed medical records of 50 consecutive patients who underwent unilateral orbital floor fracture repair in a 4-year period. Comparative analysis was performed between patients operated on within 2 weeks of injury and those operated on at a later stage. RESULTS Assault, motor vehicle accidents, and sports injuries were the most common causes of injury. Surgery was performed due to inferior rectus muscle entrapment and limitations in up gaze in 20 (40%) patients or to prevent enophthalmos in cases with significant bony orbital expansion in 30 (60%) patients. After surgery, enophthalmos improved an average of 0.8 mm. Limitation in ocular motility improved after surgery but was statistically significant only in up gaze. Patients who underwent early repair (within 2 weeks) achieved less improvement in enophthalmos versus patients who underwent late repair (delta enophthalmos of 0.2 +/- 1.1 vs 1.3 +/- 1.9 mm, respectively; P = .02). CONCLUSION In these patients, postoperative vertical ductions and postoperative enophthalmos improved after fracture repair. Surgery was associated with a low rate of postoperative complications. No apparent difference in surgical outcome was seen between early (within 2 weeks) and late surgical repair.


American Journal of Ophthalmology | 2008

Upper Eyelid Myectomy in Blepharospasm with Associated Apraxia of Lid Opening

Dan Georgescu; M. Reza Vagefi; Tristan F.W. McMullan; John D. McCann; Richard L. Anderson

PURPOSE To assess the impact of upper eyelid myectomy surgery on blepharospasm with associated apraxia of lid opening (ALO), dry eye, photophobia, and daily functioning in patients who are refractory to botulinum toxin treatment. DESIGN Noncomparative, consecutive, interventional case series. METHODS A retrospective chart review was performed to identify 100 consecutive patients beginning on January 1, 2000, who underwent upper eyelid myectomy surgery for blepharospasm and fulfilled the inclusion criteria. A survey was sent to all patients. Data were entered in an anonymous manner into a spreadsheet and analysis was performed using the Student t test with significance set at P<.05. RESULTS Forty-five (88%) patients experienced ALO before surgery, among which 15 (33%) patients stated they were completely cured and 20 (44%) others had more than 50% improvement in ALO with surgery. In 20 of 30 patients who continued botulinum toxin treatment after surgery, the effect lasted longer. Twelve (29%) of 42 patients who experienced dry eyes before surgery improved. Eighteen (41%) of the 44 patients who experienced light sensitivity before surgery improved. Thirty-seven (82%) patients noted their cosmetic appearance to be better after surgery. The cumulative preoperative disability score was 14.11+/-5.78 (59%), whereas the cumulative postoperative disability score was 5.20+/-8.25 (22%; P<.01). CONCLUSIONS Upper eyelid myectomy surgery appears to be effective in treating blepharospasm with associated ALO in most patients who are refractory to botulinum toxin injections and can provide improvement in the quality of life.


Pediatric Clinics of North America | 1990

Use of the Colposcope in Childhood Sexual Abuse Examinations

John D. McCann

The addition of the colposcope to the armamentarium of the medical investigator of childhood sexual abuse has many advantages. The ability to accurately record anatomic findings has implications for the medical community, the judicial system, the accused, the victim, and the family. Through the use of the photographs produced by this instrument, examiners can inspect physical findings without the time constraints imposed by the short attention span of the young child. If necessary, colleagues can be consulted and interpretations discussed. The availability of these photographs to the courts has reduced the need to re-examine the child for another opinion. The colposcopic photograph has also proved to be an excellent teaching and research tool. As an aid to teaching, the photographs and slides produced by this instrument help the instructor demonstrate anatomic findings while allowing the student time to ask questions. As a research tool, this instrument has opened up a myriad of possibilities for medical examiners. It has facilitated the collection of clinical data, it has allowed the standardization of examination techniques, and with the help of computers it has made possible the sophisticated analysis of the information collected. The colposcope has limitations. Aside from its cost, it is a difficult instrument to use in the examination of the young child. The time required for an examination can increase substantially as the examiner attempts to maneuver the scope into a proper position. During this procedure, the maintenance of the child in a suitable state of relaxation, while avoiding further emotional trauma, can be a challenge. The reality that the photograph is two dimensional and represents only the findings at that moment will always be a limiting factor in its use as a means of assessing a childs anatomy. Even the multimethod approach employed to offset this problem may compound the situation by further increasing the length of the examination. Most of these and other dilemmas encountered in the use of the colposcope can be solved by additional experience with this instrument. Despite the improvements brought about by the introduction of the colposcope, more advanced technology may be needed to help solve some of the problems currently plaguing medical examiners. The use of video tape could provide a solution to the documentation of the changes that occur in the soft tissues as the child moves or becomes more or less relaxed. The potential of the computer appears unlimited, and its application to the problem of the interpretation of findings could make a significant contribution to the field.(ABSTRACT TRUNCATED AT 250 WORDS)


International Ophthalmology Clinics | 2002

Benign essential blepharospasm.

John D. McCann; Suat Hayri Ugurbas; Robert A. Goldberg

Benign essential blepharospasm is a condition characterized by abnormal blinking or spasms of the eyelids. This condition is a type of dystonia, which is a group of movement disorders involving uncontrolled tensing of the muscles (muscle contractions), rhythmic shaking (tremors), and other involuntary movements. Benign essential blepharospasm is different from the common, temporary eyelid twitching that can be caused by fatigue, stress, or caffeine.


Ophthalmic Plastic and Reconstructive Surgery | 2002

Bovine hydroxyapatite orbital implant: A preliminary report

Julian D. Perry; Robert A. Goldberg; John D. McCann; Norman Shorr; Robert Engstrom; John T. Tong

Purpose To determine the safety and efficacy of bovine hydroxyapatite as an orbital implant material. Methods Prospective, consecutive case series of patients undergoing enucleation, evisceration, or secondary orbital implantation. A motility peg was placed in all consenting candidates. Patients were followed 1 week, 1 month, and several months after surgery for signs of inflammation, infection, extrusion, or other complication. Results Twenty-seven patients received a bovine hydroxyapatite orbital implant. Magnetic resonance imaging was obtained in 3 patients (3 orbits) approximately 4 weeks after surgery and showed signs of peripheral fibrovascular ingrowth in all three cases. Magnetic resonance imaging was obtained in 9 patients (9 orbits) 4 to 12 months after surgery and showed signs of incomplete fibrovascular ingrowth in 1 of 9 (11%) cases, subtotal fibrovascular ingrowth in 2 of 9 (22%) cases, and complete fibrovascular ingrowth in 6 of 9 (67%) of cases. Complications included postoperative chemosis in 3 cases (11%) and exposure requiring reoperation in 2 cases (7%). Motility peg placement was performed successfully in 5 patients (5 orbits). Conclusions Bovine hydroxyapatite appears to be a safe and effective orbital implant material. The material appears to be biocompatible and nonallergenic. Bovine hydroxyapatite allows for fibrovascular integration and motility peg placement.


Facial Plastic Surgery | 2010

Brow ptosis correction: a comparison of five techniques.

Dan Georgescu; Richard L. Anderson; John D. McCann

This study evaluates the effectiveness of five surgical techniques for brow ptosis repair including internal brow release (IBR), internal brow release with brow pexy (IBR + BP), internal brow release with corrugator and depressor supercilii removal (IBR + CDR), direct brow-lift (DB), and endoscopic brow-lift (EB). This is a retrospective study of 120 patients in which the preoperative and postoperative position of the medial, central, and lateral brow on both sides was measured. The brow was elevated 1.16 +/- 0.05 mm by IBR, 1.74 +/- 0.05 mm by IBR + BP, and 2.52 +/- 0.06 mm by IBR + CDR. IBR + BP was more effective than IBR in elevating the lateral brow ( P < 0.05). Removal of the medial brow depressors resulted in greater elevation of the medial and central brow than could be achieved with IBR or IBR + BP alone ( P < 0.01). EB resulted in the greatest amplitude of brow elevation (3.44 +/- 0.06 mm). Eyebrow-lifting surgery performed via the upper eyelid blepharoplasty incision prevents the lowering of brow position caused by blepharoplasty surgery alone. Brow pexy sutures are useful in enhancing elevation of the lateral brow, and removal of the medial brow depressors is useful in raising the medial and central brow.

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M. Reza Vagefi

University of California

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Seongmu Lee

University of California

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Tanuj Nakra

University of California

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