Ординатура / Офтальмология / Английские материалы / Oculoplasty and Reconstructive Surgery Made Easy_Garg,Touky, Nasralla_2009

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recently highlighted by burroughs et al.23 One usually needs to do excess levator correction or a two staged procedure for this extremely rare condition.

Role of steroids in childhood myasthenia: Kupersmith et al 24 studied recently the effect of treatment of myasthenia and found that children receiving prednisone showed resolution in primary gaze diplopia, downgaze diplopia, unilateral ptosis, and bilateral ptosis in 73.5%, 75.5%, 85.7%, and 98%, respectively at 1 month. The benefit persists at 3-6, 12, and 24 months except for the bilateral ptosis. The pyridostigmine group shows resolution in primary gaze diplopia, downgaze diplopia, unilateral ptosis, and bilateral ptosis in 6.9%, 17.2%, 50%, and 76.7% of patients after 1 month of treatment. Among the prednisone responsive patients, there are recurrences suggesting that 50-60 mg daily prednisone followed by lower doses (10 mg or less) has the benefit of resolving ptosis and diplopia that lasts for at least 2 years in approximately 70% of patients.

Comparison of silastic and banked fascia lata in pediatric frontalis suspension: Hersh et al 25 studied 131 frontalis suspension operations using either Silastic or banked fascia lata during the past 12 years at Children’s Hospital at Westmead, Sydney, Australia and found that functional success rates for primary frontalis suspension procedures were not significantly different for banked fascia lata and silastic (60% versus 67.2%, respectively). Infection and granuloma rates also were not significantly different (7.1% for banked fascia lata versus 15.2% for silastic). They however found a statistically significant difference between the two materials in ptosis recurrence (35.3% for banked fascia lata versus 13% for silastic) and concluded that silastic was significantly better than

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banked fascia lata in terms of ptosis recurrence. But more prospective data would be required as this study was a retrospective analysis.

Frontalis lobe suspension: A Croatian group 26 recently reported in a retrospective study their long-term results in 146 patients operated by frontal muscle lobe shaping with or without shaping of corrugator muscle lobe attached to the tarsal plate in children with congenital dystrophic ptosis.

Their criteria of postoperative success (defined as a situation with eyes open in which upper eyelid covers the cornea at 12 o’clock position by 1-2 mm; there is a good contour of the eyelid margin; there is no lagophthalmos; and there is symmetry with the other eye) was met by 91% patients at 6 months, 85% at one year, and 83% at 5 years after resurgery for undercorrection being done in 18% of patients.

Advancement of Whitnall’s ligament –conjunctival approach: Bajaj et al 27 recently did a prospective study of ptosis correction by advancement of Whitnall’s ligament by plication of the levator aponeurosis via the conjunctival route and found that good correction, i.e. within 1 mm of the normal fellow eye in primary gaze, can be obtained in 80% of patients and that patients with more than or equal to 8 mm levator function give better results. It has the advantages of shorter surgical time, minimal dissection of tissue planes and reversibility, with the conjunctival approach being cosmetically more acceptable as there is no visible scar on the lid.

Autogenous palmaris longus frontalis sling in children with congenital ptosis: Wong et al 28 investigated the long-term outcome of using autogenous palmaris longus tendon sling for correcting congenital ptosis in children with age ranging from 2 to 7 years with a mean follow-up of 92 months (range,

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80-104 months), and noted found that all eyelids were successfully corrected with good lid height. No recurrence or other postoperative complications were encountered except one patient who developed a small skin fold over the harvest site. It could be a good alternative to autogenous fascia lata, and further studies, to compare these two sling materials seem warranted.

Complication of surgery—inverse Bell’s phenomenon: Betharia et al 29 reported three patients who underwent levator resection and showed an inversion of the Bell’s phenomenon in the postoperative period, with the eye going down instead of up, during eyelid closure. This highlights the need for evaluating the bells phenomenon not only preoperatively but also postoperatively.

ORBITAL IMPLANTATION IN CHILDREN

Figure 4: Traumatic globe rupture and orbital implant with cornea preserving evisceration

Orbital implants are used regularly in pediatric patients at the time of enucleation. The commonest indications for enucleation are retinoblastoma, blind eye following trauma and end stage retinopathy of prematurity. Controversy

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regarding the rate of complications with newer implants in the pediatric population continues to confuse clinicians.

Size of Implant30

The average percent volume replaced by the implants in adult patients is 68%. The average percent volume replaced by the implants in pediatric patients is 21%. Up to seventy-one percent of pediatric patients undergo secondary implant surgery to augment volume and eliminate superior sulcus deformity and enophthalmos. The placement of an adequately sized implant in pediatric patients may obviate the need for secondary augmentation of socket volume in adulthood. Some authors suggest an implant 2 mm less in diameter than the axial length of the eye in pediatric patients.

Primary Orbital Implants in Children–Hydroxyapatite

Christmas et al31 studied 120 child eyes implanted and found that implant exposure rate was 0.8%, implant extrusion was not seen and implant migration rate was 2.4%. Of all patients 96% had good cosmesis and 98% had good motility and concluded that orbital implantation after enucleation is successful in the pediatric population and complications are minimal. Hydroxyapatite implants are not associated with unacceptable complications in the pediatric population.

Porous Polyethylene Implant in a Child

Iordanidou et al32 studied prospectively the incidence of complications of primary insertion of porous polyethylene orbital implant in the pediatric population who underwent primary placement of an anteriorly wrapped spherical porous

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polyethylene orbital implant with at least 17 months of followup weeks and found that there were no cases of implant extrusion, superior sulcus syndrome, orbital cellulitis, or significant inflammatory response.

The spherical implant size used may be 16 mm, 18 mm or 20 mm. The prosthesis is generally fitted after an interval of 5 weeks and usually the porous polyethylene orbital implant is now not drilled for peg placement. Anteriorly wrapped primary porous polyethylene orbital implant in the pediatric population appears to be well tolerated with few complications even in the author’s experience. Kim et al33 have noted a 33% exposure rate in eyes that had conventional enucleation and porous poly ethylene implantation, and none if a free orbital fat graft in addition suggesting that a free orbital fat graft is a simple, effective way to prevent orbital implant exposure in patients requiring enucleation and implantation.

Autogenous Dermis-fat Graft Orbital Implant

Mitchell et al34 studied autogenous dermis-fat graft orbital implants and found that all implants maintained appropriate volume allowing proper prosthetic fit and facial symmetry. Soome children experience excessive growth of their implants but that can be managed by surgical debulking. Some children develop a central graft ulcer, which can be managed by superficial revision and reclosure. It is indeed a promising implant for the pediatric anophthalmic socket.

Moreker’s Expandable Balloon Implants

These can be used in severe anophthalmic sockets which are contracted, so as to expand them.

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and that patients with trapdoor fractures who present with nausea/vomiting are at a high risk of inferior rectus entrapment and poor outcome. Egbert et al 38 reported that preoperative nausea and vomiting are immediately relieved after surgery. The median time for improvement of preoperative duction deficits and diplopia is 4 days for patients receiving surgery within 7 days and 10 days for those undergoing surgery after 14 days. Resolution of duction deficits or diplopia is not dependent on time of surgery if performed within 1 month of injury. For patients with severe limitation of ductions, early surgical repair within 7 days of injury results in more rapid improvement of ductions and diplopia than surgery performed later. Jordan et al 39 called it the “white eyed fracture” and reported that a 2-week waiting period has been found to be of little benefit in these persons and possibly harmful to their motility. They advocated surgery within the first few days after injury as it may help to avoid permanent motility restriction.

We (authors) perform orbital wall reconstruction with Prolene/ Medpor barrier sheet implantation (thickness 1mm) through transconjunctival approach under endoscopic guidance and at times whenever possible we do a complete endoscopic correction

Endoscopic Fracture Reduction and Mesh Implantation with Tissue Glue

A completely endoscopic approach transnasally with reduction of the trapdoor fracture fragments with endoscopically guided mesh kept in place by fironectin glue is done by the authors (Dr Milind Kirtane and Dr Sunil Moreker) at their institute (P.D Hinduja National Hospital and MRC,Bombay) and videos of the same were presented at

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LID AND ORBITAL TUMORS

Most pediatric orbital tumors are benign; developmental cysts comprise half of orbital cases, with capillary hemangioma being the second most common orbital tumor. The most common orbital malignancy is rhabdomyo-sarcoma. The most common intraocular malignant lesion is retinoblastoma. Choroidal melanoma, which is common in adults, is extremely rare in children. The orbit is the most common location for metastases in children, whereas the choroid is the predominant site in adults. Metastases to the orbit in childhood may be due to solid tumors such as a neuroblastoma or Ewing’s tumor. Orbital cysts are quite common and varied.

Shields Classification of Orbital Cysts40

The major categories in the classification include

a.Cysts of surface epithelium,

i.Simple epithelial cyst (epidermal, conjunctival, respiratory, and apocrine gland), and

ii.Dermoid cyst (epidermal and conjunctival).

b.Teratomatous cysts,

c.Neural cysts—include those associated with ocular maldevelopment (congenital cystic eye and colobomatous cyst) and those associated with brain and meningeal tissue (cephalocele and optic nerve meningocele).

d.Secondary cysts—most common mucocele that can occur in children with cystic fibrosis.

e.Inflammatory cysts, generally due to parasitic infestations and are more common in tropical areas of the world.

f.Noncystic lesions with cystic component—include adenoid cystic carcinoma, rhabdomyosarcoma, lymph-angioma, and others.

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Epidermal dermoid cyst (dermoid) is by far the most common orbital cystic lesion in children, accounting for over 40% of all orbital lesions of childhood and for 89% of all orbital cystic lesions of childhood that come to biopsy or surgical removal. Dermoid cysts are unusual neoplasms that often present in childhood, with the orbit being the area most commonly affected in the head and neck region. Imaging studies help rule out an intracranial or intraorbital extension. With complete excision, recurrence is unusual.41

Figure 8: Dermoid—pre- and immediate postoperatively