Ординатура / Офтальмология / Английские материалы / Oculoplasty and Reconstructive Surgery Made Easy_Garg,Touky, Nasralla_2009
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Endoscopic Dacryocystorhinostomy 439
G.Trauma
H.Radiation therapy
EXAMINATION
Punctum
Pouting puncti, stenosis, canaliculitis and ectropion punctum or entropion punctum (Figures 1A and B).
Figures 1A and B
Sac Syringing
Syringing is a primary procedure done as part of the evaluation of epiphora. A drop of anesthetic is instilled in the conjunctival sac and then irrigated with normal saline. A punctum dilator can be used before inserting the cannula if the punctum is too small. Before the test the patient is told that the saline may pass into the nose and throat and asked to inform the clinician if he/she feels it in the throat. Syringing is usually done through the lower punctum as it is easily accessible but can be done through both puncta. If the saline passes through the NLD and reaches the throat it is patent and there is no anatomical obstruction. A patent syringing can indicate a physiological cause for obstruction. If the saline regurgitates through the opposite punctum, then there is a block at the common canaliculus or upper sac. If the saline
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regurgitates through the same punctum, then the punctum which is being tested is blocked. There can also be a partial block in the NLD where the patient feels a small amount of saline in the throat and some of it regurgitates. Probing can be performed after syringing to determine where the block is. On probing if you reach a hard stop it means that the common canaliculus is patent. But if you reach a soft stop then obstruction of the common canaliculus can be suspected hard versus a soft stop.
The Jones Test
The test is done by instilling fluorescein in the conjunctival sac andvisualizingitinthenoseafteraperiodoffiveminutes. Ifdye not seen in the nose after five minutes, then a secondary test is done, by irrigating the duct. If after irrigating the duct no dye is found in the nose, the dye has never really reached the lacrimal sac to begin with and it’s a partial obstruction. If dye is seen by irrigation, it is likely to be pump failure.
Dacryocystogram
For the dacryocystogram, the patient is in supine position and the contents of the sac should be first emptied by massage and irrigated thoroughly with saline to remove any residual mucoid material. After placing a topical anesthetic in the conjunctival sac, the radiopaque dye is then injected in the lacrimal sac through a tube in the punctum. Radiographs are taken as soon as the dye is injected. They are usually obtained in the posteroanterior view and lateral view.
Indications for DCG
•Complete obstructions of the lacrimal system: If you reach a soft stop during syringing suggesting a complete
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obstruction, DCG will determine if the obstruction is in the canaliculus or the sac.
•Incomplete obstructions: in incomplete obstructions it will give us the exact location of the blockage.
•Tumors of the lacrimal sac are assessed with DCG.
•Previous lacrimal sac surgery.
A DCG can cause little discomfort to the patient and does not allow any physiological assessment of the lacrimal sac. A preoperative radiograph DCG can be placed on the view box in the operating room. This could be helpful while performing the operation (Figure 2).
Figure 2
Dacryoscintigraphy with Radiolabeled Materials
Lacrimal Dacryoscintigraphy (LDS)
LDS is a form of nuclear imaging of the lacrimal sac. A drop of radionuclide is instilled in the palpebral aperture or conjunctival sac. Radiographic images are taken to follow the radionuclide through the lacrimal system. The patient is advised to blink normally and the images are taken every 10 seconds for the first 2-3 minutes and then every 5 minutes for a total of 20 minutes.
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Indications for LDS
•Complaint of epiphora even with patent syringing: if syringing is patent it could indicate a functional black like lacrimal pump failure, even though the anatomy of the lacrimal system is normal.
•Patients with Lid Laxity: LDS can determine if the lid laxity is the cause for lacrimal pump failure.
•Assessment of Punctal occlusion: LDS can determine the efficacy of punctal occlusion.
LDS causes less discomfort for the patient, as there is not
tube to be inserted. Studies have shown that LDS is a marginally superior technique to DCG. LDS gives us physiologic or functional information about the lacrimal sac, but no anatomic details.2 Thus, LDS needs to be done in conjunction with a DCG or syringing and cannot be the only diagnostic procedure. LDS has also been shown to be more sensitive in detecting abnormalities in the upper lacrimal system.
All three procedures; syringing, DCG and LDS have to be performed complementary to each other and cannot indicate the cause for epiphora alone (Figure 3).
Figure 3
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Extrinsic Tumors
CT scan2 to exclude extrinsic tumors, lacrimal sac mucoceles, the state of the sinuses and dacryoliths for you.
ENDOSCOPIC DCR
First described by McDonogh in 1989.The anterior portion of the middle turbinate is used as a landmark. A mucosal flap is elevated, exposing the lacrimal fossa. This bone is drilled out, that is the frontal process of the maxillary bone and some of the lacrimal bone, exposing the nasal lacrimal sac. A probe is used to tent the sac, and the sac is incised to create a ostium so that tears can drain from the canaliculus directly into the nose through the middle turbinate and bypass any obstruction in the nasolacrimal duct. This ostium is kept open with a tube stent with a silicone tube placed through the puncta into the sac and out the nose. The tubes are retained for six months.
Advantages of the Endoscopic DCR
A.There is no external scar.
B.It preserves the lacrimal pump system.
C.Any intranasal pathology that might have caused failure of the first procedure can be corrected, including adhesions, enlarged middle turbinate and septal deviation (Figure 4).
D.Negative pressure was detected during blinking and forced blinking in all normal subjects and in most patients who had successfully undergone DCR. In contrast, positive pressure was detected in cases with epiphora and patients in whom DCR had failed. Negative pressure was higher after endoscopic than external DCR. During the Valsalva maneuver there were no pressure changes in normal cases and patients with epiphora. In contrast, positive pressure was detected after all of the successful procedures (being
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Figure 4
higher after external than endoscopic DCR) and in most of the patients in whom external DCR failed. In normal subjects, negative pressure is created during blinking. In cases with epiphora due to NLD obstruction, the lacrimal pump is affected but its function is restored after successful DCR. The suction power of the pump mechanism is more effective after endoscopic than external (Acta OtoLaryngologica, Volume 123, Issue 2 February 2003; pp 325-9).
Disadvantages
A.No Mucosal flaps made -Mucosal flaps have been found to decrease recurrence rates in the external procedures.
B.A smaller rhinostomy is performed in Endo DCR than in the external procedure
C.No suturing of flaps.
Complications
A.Closure of the ostium
B.Intranasal adhesions
C.Canalicular laceration
D.Pyogenic granuloma
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E.CSF leak
F.Orbital hemorrhage can occur from the interior ethmoid artery during the endoscopic procedure
Comparison of External and Endo-DCR
Hartikainen et al3,4 did a prospective study comparing endoscopic to external DCR of 64 patients followed up for one year. He found a patency rate of 75% in the endoscopic cases versus 91% externally. This did not, however, reach a statistically significant difference. After revision procedures, there was a 97% success rate in both groups.
Lasers in DCR5-8
A.Massaro5 used an Argon laser
B.Holmium-Yag8 laser has advantages of fiberoptic delivery, effective bone ablation, soft tissue coagulation and shallow depth of penetration, which makes it safer.
C.KTP laser
Adjuvants in DCR
Mitomycin-C9,10 an alkylating agent has been found useful by Camara et al11 improving success rate for endoscopic DCRs from 89 to 99% with no complications.
RECENT MODIFICATIONS
A.The new technique involved creation of a large bony ostium and mucosal flaps12 to create an anastomosis between the lacrimal sac mucosa and nasal mucosa.
B.Mechanical endonasal dacryocystorhinostomy (MENDCR)13 creation of a large ostium as well as mucosal flaps improves the efficacy of this endonasal technique.
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C.Modified endoscopic dacryocystorhinostomy with posterior lacrimal sac flap14 for nasolacrimal duct obstruction.The new technique involved the creation of a large posterior flap at the medial lacrimal sac wall, reflecting it posteriorly, followed by removal of the remaining small anterior flap
D.Moreker Kirtane Suturing of Endoscopic nasal and sac flaps in Endonasal DCR-the authors follow a technique of suturing of the nasal and sac flaps in endoscopic DCR (video enclosed)
E.Moreker Mankekar technique of Tissue glue for apposing flaps-The authors follow a technique of holding the nasal and sac flaps with tissue fibronectin glue (video enclosed)
REFERENCES
1.Yung MW, Logan BM. The anatomy of the lacrimal bone at the lateral wall of the nose: its significance to the lacrimal surgeon. Clin Otolaryngol 1999;24:262-65.
2.Francis IC, Kappagoda MB, Cole IE, Bank L, Dunn GD. Computed tomography of the lacrimal drainage system: retrospective study of 107 cases of dacryostenosis. Ophthal Plast Reconstr Surg 1999;15:21726.
3.Hartikainen J, Grenman R, Puuka P, Seppa H. Prospective randomized comparison of external dacryocystorhinostomy and endonasal laser dacryocystorhinostomy. Ophthalmology 1998;105:1106-13.
4.Hartikainen J, Antila J, Varpula M, Puuka P, Seppa H, Grenman R. Prospective randomized comparison of endonasal endoscopic dacryocystorhinostomy and external dacryocystorhinostomy. Laryngoscope 1998;108:1861-66.
5.Massaro BM, Gonnering RS, Harris GI. Endonasal laser dacryocystorhinostomy: a new approach to nasolacrimal duct obstruction. Arch Ophthalmol 1990;108:1172-6.1989;103: 585-7.
6.Metson R, Woog JJ, Puliafito CA. Endoscopic laser dacryocystorhinostomy. Laryngoscope 1994;104:269-274.
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7.Meullner K, Bodner E, Mannor GE, Wolf G, Hoffman T, Luxenberger W. Endolacrimal laser assisted lacrimal surgery. Br J Ophthomol 2000;84:16-8.
8.Sadiq SA, Hugkulstone CE, Jones NS, Downes RN. Endoscopic holmiun:YAG laser dacryocystorhinostomy. Eye 1996;10:43-6.
9.Szubin L, Papageorge A, Sacks E. Endonasal laser-assisted dacryocystorhinostomy. Am J Rhinol 1999;13:371-4
10.Weidenbecher M, Hoseman W, Buhr W. Endoscopic endonasal dacryocystorhinostomy: results in 56 patients. Ann Otol Rhinol Laryngol 1994;103:363-7.
11.Camara JG, Bengzon AU, Henson RD. The safety and efficacy of mitomycin C in endonasal endoscopic laser-assisted dacryocystorhinostomy. Ophthal Plast Reconstr Surg 2000;16:114-8.
12.Tsirbas A, Wormald PJ. Endonasal dacryocystorhinostomy with mucosal flaps. Am J Ophthalmol. 2003 Jan;135(1):76-83.
13.Tsirbas A, Wormald PJ. Mechanical endonasal dacryocystorhinostomy with mucosal flaps.Br J Ophthalmol. 2003 Jan;87(1):43- 7.
14.Yuen KS, Lam LY, Tse MW, Chan DD, Wong BW, Chan WM. Modified endoscopic dacryocystorhinostomy with posterior lacrimal sac flap for nasolacrimal duct obstruction. Hong Kong Med J. 2004 Dec;10(6):394-400.
PLICATION OF ORBICULARIS OCULI FOR PTOSIS
The surgery involves the exposure of the orbicularis oculi muscle, by making a skin flap that starts from near the upper orbital margin downwards. The orbicularis oculi fibers near the lid margin are joined to the proximal orbicularis fibers with the help of 80 microns stainless steel sutures.
Steps of Operation
Exposure of the Orbicularis Oculi Muscle
A skin-deep curved incision with its convexity towards the orbital margin is made. The central highest point of the convexity is about 5 to 7 mm from the orbital margin. The incision line slopes gently towards the either end. The ends are kept away from the lid margin by at least 7-8 mm (Figures 1 and 2).
The skin is carefully separated from the underlying orbicularis oculi muscle close to the incision line. It is then progressively undermined and separated, right up to the lid margin. During the process of undermining and separation of the skin, the tip of the blunt curved corneal scissors is kept directed towards the skin, so that the orbicularis muscle is not excessively injured or carried along with the skin. A clean dissection in the right plane minimizes oozing of the blood.