Marcus M. Marcet
University of Hong Kong
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Ophthalmology | 2011
Kenneth V. Cahill; Elizabeth A. Bradley; Dale R. Meyer; Philip L. Custer; D. E. E. Holck; Marcus M. Marcet; Louise A. Mawn
OBJECTIVE To evaluate the functional indications and outcomes for blepharoplasty and blepharoptosis repair by assessing functional preoperative impairment and surgical results. METHODS Literature searches of the PubMed and Cochrane Library databases were conducted on July 24, 2008, with no age or date restrictions, and they were limited to articles published in English. These searches retrieved 1147 citations; 87 studies were reviewed in full text, and 13 studies met inclusion criteria and were included in the evidence analysis. RESULTS The 13 studies reported the functional effects or treatment results of simulated ptosis; several types of blepharoptosis repair, including conjunctiva-Müllers muscle resection, frontalis suspension, and external levator resection; and upper eyelid blepharoplasty. CONCLUSIONS Repair of blepharoptosis and upper eyelid dermatochalasis provides significant improvement in vision, peripheral vision, and quality of life activities. Preoperative indicators of improvement include margin reflex distance 1 (MRD(1)) of 2 mm or less, superior visual field loss of at least 12 degrees or 24%, down-gaze ptosis impairing reading and other close-work activities, a chin-up backward head tilt due to visual axis obscuration, symptoms of discomfort or eye strain due to droopy lids, central visual interference due to upper eyelid position, and patient self-reported functional impairment. FINANCIAL DISCLOSURE(S) The author(s) have no proprietary or commercial interest in any materials discussed in this article.
Current Opinion in Ophthalmology | 2014
Marcus M. Marcet; Andrew K.T. Kuk; Paul O. Phelps
Purpose of review To review the current surgical practices in endoscopic endonasal dacryocystorhinostomy (EN-DCR) from the studies of last 12 months. Recent findings Success rates in EN-DCR now rival those of the conventional external approach. Indications are expanding beyond primary acquired nasolacrimal duct obstruction to include DCR revisions, acute lacrimal sac abscesses, nasolacrimal duct obstructions in patients who have received chemotherapy or radiation, and common canalicular obstructions. There is limited evidence that intubation with silicone stents improves the outcomes. Mitomycin C appears to improve the success rates of EN-DCR, especially revision surgery. Concomitant procedures, such as septoplasty and anterior middle turbinectomy, are sometimes required in primary as well as revision EN-DCR to achieve high success rates. There is increasing evidence that silicone stents are of limited benefit, whereas mucosal flap formation has been of benefit in case series. Summary With innovations and improvements in the endonasal approach, EN-DCR has become a viable alternative to external DCR for primary acquired nasolacrimal duct obstruction. EN-DCR has the distinct advantages of no surface scar and a lack of damage to the pump mechanism that often occur with external DCR. Recent evidence indicates a comparable success rate to external DCR.
Ophthalmic Plastic and Reconstructive Surgery | 2010
Marcus M. Marcet; Pete Setabutr; Bradley N. Lemke; Megan E. Collins; James C. Fleming; Ralph E. Wesley; Jayant M. Pinto; Allen M. Putterman
Purpose: To assess for alterations in the microscopic anatomy that occur as a result of the Müller muscle-conjunctival resection (MMCR) ptosis procedure and to better understand the mechanisms by which MMCR elevates the eyelid. Methods: Sixteen orbits from 8 fresh frozen Caucasian cadaver heads, ranging from 38 to 100 years of age were used. For each head, MMCR was performed on one side. The contralateral, unoperated orbit served as an anatomic control. Each exenterated orbital contents and excised MMCR specimen was evaluated. The histopathology of the eyelids and MMCR specimens were studied microscopically by staining with hematoxylin-eosin, elastic, and Verhoeff-Masson trichrome. Results: Müller muscle and conjunctiva were present in all 8 of the excised MMCR specimens. Elastic fibers consistent with Müller muscle tendon or among the smooth muscle fibers were seen within all excised MMCR specimens. The levator aponeurosis was intact in 8 of 8 operated eyelids; however, the aponeurosis was plicated in all. The accessory lacrimal gland tissues were intact in all of the operated and unoperated eyelids. Conclusions: MMCR works by shortening the posterior lamella, which results in advancement of the levator palpebrae superioris muscle and plication of the levator aponeurosis. Plication of the levator aponeurosis likely contributes to the increased volumetric effect seen clinically after MMCR. Phenylephrine testing can help in fine-tuning the amount of resection, but given the mechanism of action of MMCR, adequate levator muscle function remains a critical factor in the success of the surgery. Moreover, MMCR preserves accessory lacrimal gland tissues.
Ophthalmology | 2015
Marcus M. Marcet; Roni M. Shtein; Elizabeth A. Bradley; Sophie X. Deng; Dale R. Meyer; Jurij R. Bilyk; Michael T. Yen; W. Barry Lee; Louise A. Mawn
OBJECTIVE To review the published literature assessing the efficacy and safety of lacrimal drainage system plug insertion for dry eye in adults. METHODS Literature searches of the PubMed and Cochrane Library databases were last conducted on March 9, 2015, without date restrictions and were limited to English language abstracts. The searches retrieved 309 unique citations. The primary authors reviewed the titles and abstracts. Inclusion criteria specified reports that provided original data on plugs for the treatment of dry eyes in at least 25 patients. Fifty-three studies of potential relevance were assigned to full-text review. The 27 studies that met the inclusion criteria underwent data abstraction by the panels. Abstracted data included study characteristics, patient characteristics, plug type, insertion technique, treatment response, and safety information. All studies were observational and rated by a methodologist as level II or III evidence. RESULTS The plugs included punctal, intracanalicular, and dissolving types. Fifteen studies reported metrics of improvement in dry eye symptoms, ocular-surface status, artificial tear use, contact lens comfort, and tear break-up time. Twenty-five studies included safety data. Plug placement resulted in ≥50% improvement of symptoms, improvement in ocular-surface health, reduction in artificial tear use, and improved contact lens comfort in patients with dry eye. Serious complications from plugs were infrequent. Plug loss was the most commonly reported problem with punctal plugs, occurring on average in 40% of patients. Overall, among all plug types, approximately 9% of patients experienced epiphora and 10% required removal because of irritation from the plugs. Canaliculitis was the most commonly reported problem for intracanalicular plugs and occurred in approximately 8% of patients. Other complications were reported in less than 4% of patients on average and included tearing, discomfort, pyogenic granuloma, and dacryocystitis. CONCLUSIONS On the basis of level II and III evidence in these studies, plugs improve the signs and symptoms of moderate dry eye that are not improved with topical lubrication, and they are well tolerated. There are no level I studies that describe the efficacy or safety of lacrimal drainage system plugs.
Investigative Ophthalmology & Visual Science | 2014
John C. Dreixler; Jacqueline N. Poston; Irina V. Balyasnikova; Afzhal R. Shaikh; Kelsey Y. Tupper; Sineadh Conway; Venkat Boddapati; Marcus M. Marcet; Maciej S. Lesniak; Steven Roth
PURPOSE Delayed treatment after ischemia is often unsatisfactory. We hypothesized that injection of bone marrow stem cell (BMSC) conditioned medium after ischemia could rescue ischemic retina, and in this study we characterized the functional and histological outcomes and mechanisms of this neuroprotection. METHODS Retinal ischemia was produced in adult Wistar rats by increasing intraocular pressure for 55 minutes. Conditioned medium (CM) from rat BMSCs or unconditioned medium (uCM) was injected into the vitreous 24 hours after the end of ischemia. Recovery was assessed 7 days after ischemia using electroretinography, at which time we euthanized the animals and then prepared 4-μm-thick paraffin-embedded retinal sections. TUNEL and Western blot were used to identify apoptotic cells and apoptosis-related gene expression 24 hours after injections; that is, 48 hours after ischemia. Protein content in CM versus uCM was studied using tandem mass spectrometry, and bioinformatics methods were used to model protein interactions. RESULTS Intravitreal injection of CM 24 hours after ischemia significantly improved retinal function and attenuated cell loss in the retinal ganglion cell layer. CM attenuated postischemic apoptosis and apoptosis-related gene expression. By spectral counting, 19 proteins that met stringent identification criteria were increased in the CM compared to uCM; the majority were extracellular matrix proteins that mapped into an interactional network together with other proteins involved in cell growth and adhesion. CONCLUSIONS By restoring retinal function, attenuating apoptosis, and preventing retinal cell loss after ischemia, CM is a robust means of delayed postischemic intervention. We identified some potential candidate proteins for this effect.
The Journal of Steroid Biochemistry and Molecular Biology | 2005
Daniel M. Albert; Lori A. Plum; William Yang; Marcus M. Marcet; Mary J. Lindstrom; Margaret Clagett-Dame; Hector F. DeLuca
OBJECTIVES To investigate the effectiveness of 2-methylene-19-nor-(20S)-1alpha-hydroxybishomopregnacalciferol (2MbisP) in inhibiting the growth of retinoblastoma (RB) and neuroblastoma (NB). METHODS For the RB study, the xenograft athymic mouse/human retinoblastoma cell (Y-79) model and the transgenic beta-luteinizing hormone-large T antigen (LHbeta-Tag) mice were systemically treated with 2MbisP or vehicle for 5 weeks. For the NB study, the xenograft athymic mouse/human neuroblastoma cell (SK-N-AS) model was treated with 2MbisP or vehicle for 5 weeks. Tumor size and toxicity were assessed. RESULTS In the xenograft models of RB and NB, 2MbisP caused statistically significant inhibition of tumor growth. Tumor growth inhibition was also observed in the transgenic RB mice, but did not achieve statistical significance. In all the groups, no biologically significant toxic effects were observed using the following variables: serum calcium levels, degree of kidney calcification, changes in body weight or survival. CONCLUSIONS In athymic mice, 2MbisP was effective in inhibiting RB and NB growth compared with controls. A lesser effect was seen in the transgenic RB model. 2MbisP did not cause hypercalcemia or a significant increase in mortality. CLINICAL RELEVANCE 2MbisP should be considered for use in clinical trials of RB and NB.
Current Opinion in Ophthalmology | 2015
Marcus M. Marcet; Paul O. Phelps; Jimmy S. M. Lai
Purpose of review To review current surgical practices for the repair of lower eyelid involutional entropion with a focus on recent studies. Recent findings A shorter axial length, which may be interrelated with exophthalmometry, correlates with involutional entropion. Although it is known Asian eyelids more frequently develop involutional entropion, there is greater awareness of customized surgical approaches. Minimally invasive techniques for strengthening the action of lower eyelid retractors, such as everting sutures and transconjunctival approaches, continue to be refined and studied. Such surgery is efficacious in patients who do not have horizontal laxity. However, there is consistent evidence that in the presence of laxity the recurrence rate is higher if the eyelid is not horizontally tightened. Summary By knowing of the demographics and factors associated with involutional entropion, clinicians can have better understanding of the condition and the patients most at risk. There is not sufficient evidence to determine whether a short axial length is an independent-risk factor for entropion. Advances in surgical technique have led to continued interest in minimally invasive approaches. Precision in addressing individual patients’ underlying anatomic abnormalities is important.
Ophthalmology | 2013
Marcus M. Marcet; Dale R. Meyer; Mark J. Greenwald; Steven Roth; Dinesh Selva
PURPOSE To examine the tarsal attachments of the levator aponeurosis. DESIGN Experimental anatomic study. PARTICIPANTS Sixteen orbits from 12 fresh frozen white cadavers. METHODS Eight specimens served as controls. In the remaining 8 specimens from 4 cadavers, the upper eyelid was everted. All specimens then were fixed in formalin. The age, sex, and laterality were recorded in both groups. The eyelid lamellae and tarsal attachments of the levator aponeurosis in particular were examined microscopically. Lamellar and nonlamellar ocular anatomic features and the relationships of the preaponeurotic and postaponeurotic spaces were measured. MAIN OUTCOME MEASURES Histologic findings of the extent and pattern of the tarsal attachments of the levator aponeurosis in relation to the tarsus and Müllers muscle and of the changes in the lamellae in eyelid eversion. RESULTS The demographic and baseline anatomic characteristics of both the noneverted control and everted eyelid groups were similar. In comparing everted with noneverted controls, the preaponeurotic space was significantly shorter (6.22 and 10.61 mm, respectively; P = 0.003) and the preaponeurotic-to-postaponeurotic space ratio was halved (0.57 and 1.16, respectively; P = 0.005). Although the distance from the superior tarsal border to Whitnalls ligament increased significantly in everted versus noneverted eyes (14.65 and 11. 03 mm, respectively; P = 0.016), there was no significant difference in the length of postaponeurotic space in the 2 groups (11.07 and 9.69 mm, respectively; P = 0.370). The levator aponeurosis attached to the anterior tarsus in both groups. The proximal point of attachment was the superior border of the tarsal plate, adjacent to the insertion of Müllers muscle tendon. CONCLUSIONS The deeper aponeurotic fibers and Müllers muscle attach proximally at the superior tarsal border. Upon eyelid eversion, the 2 lamellae move as a unit and the postaponeurotic space remains stable. A proximal tarsal attachment suggests that blepharoptosis procedures that advance an involutional or disinserted levator aponeurosis onto to the superior tarsus approximate that aspect of native anatomic features. In addition, posterior surgical approaches that address Müllers muscle may involve resections in closer proximity to the aponeurosis than previously thought. FINANCIAL DISCLOSURE(S) The author(s) have no proprietary or commercial interest in any materials discussed in this article.
Ophthalmic Plastic and Reconstructive Surgery | 2005
Marcus M. Marcet; John J. Woog; Bellows Ar; Mandeville Jt; Maltzman Js; Khan J
A retrospective case series of 2 patients with orbital complications after tube shunt placement for glaucoma is reported. The first patient presented with limited motility and conjunctival injection in the setting of intraocular gas leakage in the superior orbit after previous vitreoretinal surgery. The second patient presented with multiple signs of orbital cellulitis. Both patients improved with intravenous antibiotics. Although rare, orbital complications may occur after glaucoma tube shunt surgery.
Orbit | 2013
Soo Khai Ng; WengOnn Chan; Marcus M. Marcet; Hirohiko Kakizaki; Dinesh Selva
ABSTRACT The levator palpebrae superioris (LPS) muscle is the main retractor of the upper eyelid, responsible for elevating the upper eyelid and maintaining it in an open position. Sound knowledge of its anatomy and adjacent structures is essential for eyelid surgery. Work from researchers and anatomists over the years continue to enrich our understanding in the anatomy of the LPS. In this review, we present an update on the anatomy of the LPS and its surgical implications. Important adnexa such as Whitnalls ligament, intermuscular-transverse ligament and Müller’s muscle are also covered.