Involutional entropion repair with fornix sutures and lateral tarsal strip procedure

PURPOSE: To evaluate the long-terrm effectiveness of fornix suture placement combined with a lateral tarsal strip procedure in correcting involutional entropion. Published reports regarding various surgical techniques and results are reviewed. METHODS: This retrospective study reviewed 119 patients with involutional lower eyelid entropion who underwent surgical repair between January 1987 and May 1999 at the Bascom Palmer Eye Institute. Exclusion criteria included follow-up duration of less than 6 months, previous lower eyelid blepharoplasty, previous conjunctival surgery other than chalazion removal, or cicatricial entropion. The three surgical subsets were (1) combined lateral tarsal strip and fornix sutures: (2) fornix sutures alone; and (3) lateral tarsal strip procedure alone. The chart review was complemented by a telephone questionnaire to assess the long-term clinical outcome, complications, and patient satisfaction. RESULTS: One hundred fifty-two eyelids in 119 patients were included. One hundred twenty-five eyelids had combined surgery (lateral tarsal strip with fornix sutures), 9 eyelids had only fornix suture repair, and 18 eyelids had repair with only the lateral tarsal strip procedure. The recurrence rate in these three surgical subsets was 1.6%, 33%, and 22%, respectively, with average follow-up of 36 months. One case of incisional cellulitis was encountered. Postoperative ectropion was not seen in the group having the combined lateral tarsal strip and fornix suture procedure. CONCLUSIONS: Suture advancement of the lower eyelid retractors in conjunction with a lateral tarsal strip procedure is a simple, quick, physiologic, and effective approach in achieving long-lasting correction for involutional entropion.     

The buried vertical mattress: a simplified technique for eyelid margin repair

We describe a new approach for the closure of eyelid margin defects. We conducted a prospective evaluation of patients undergoing the buried vertical mattress technique for full-thickness eyelid margin repair and found that 90 patients (follow-up, 3 to 18 months; average, 6 months) had eyelid margin defects closed with the use of a buried vertical mattress technique. There were no cases of dehiscence, and only 5 (5.5%) patients had minor notch formation. We conclude that the buried vertical mattress suture technique can be a safe and effective method to close eyelid margin defects while saving postoperative time and the cost of multiple sutures.     

Blepharoptosis Repair through the Small Orbital Septum Incision and Minimal Dissection Technique in Patients with Coexisting Dermatochalasis

Purpose

To describe a modified surgical technique for blepharoptosis repair through a small orbital septum incision and minimal dissection, along with the results obtained in patients with coexisting dermatochalasis.

Methods

A retrospective chart review included 33 patients (52 eyelids) with blepharoptosis coexisting with dermatochalasis, surgically corrected through a small orbital septum incision and minimal dissection after redundant upper lid skin excision, by placing a single fixation suture between the levator aponeurosis and the tarsal plate. Outcome measures included the pre- and postoperative marginal reflex distances (MRD1), eyelid contour, post-operative complications, and need for reoperation.

Results

The pre- and postoperative MRD1 averaged 1.1 ± 0.8 mm and 2.8 ± 1.1 mm, respectively. Of the 33 patients, 9 patients (9 eyelids) underwent surgery on one eyelid for unilateral blepharoptosis and dermatochalasis (Group I), 5 patients (5 eyelids) underwent a simple skin excision blepharoplasty of the contralateral eyelid (Group II), and 19 patients (38 eyelids) underwent bilateral blepharoptosis and dermatochalasis repair (Group III). Of the 14 eyelids that underwent unilateral ptosis repair (Groups I and II), 12 eyelids (85.7%) showed less than a 1-mm difference from the contralateral eyelid. Of the 38 eyelids that underwent bilateral ptosis repair (Group III), 27 eyelids (71.1%), 5 eyelids (13.1%), and 6 eyelids (15.8%) had excellent, good, and poor outcomes, respectively. Overall, 44 eyelids (84.6%) out of a total of 52 eyelids had successful outcomes; the remaining 8 eyelids demonstrated unsatisfactory eyelid contour was corrected by an additional surgery.

Conclusions

Blepharoptosis repair through a small orbital septum incision and minimal dissection can be considered an efficient technique in patients with ptosis and dermatochalasis.     

Eyelid retractor surgery as an adjunct to cicatricial ectropion repair

Purpose : To evaluate the effectiveness of eyelid retractor repair in cicatricial ectropion of the lower eyelid. Methods : The study design was a prospective case series. One hundred and twenty eight eyelids were operated on in 100 consecutive patients with cicatricial ectropion. All patients underwent lower eyelid retractor repair via a conjunctival approach combined with skin replacement to the anterior lamella with or without a horizontal lid tightening procedure. When only medial ectropion was present, a medial‐based transpositional skin flap was used to repair the anterior lamella (26 eyelids). The remaining eyelids with ectropion involving all or most of the eyelid underwent upper‐to‐lower eyelid lateral‐based transpositional skin flap repair (92 eyelids), or full thickness free skin grafting (10 eyelids). Horizontal lid tightening was performed by lateral canthoplasty in 123 eyelids. Results : Relief of cicatricial ectropion symptoms was reported in 90% of patients overall. A normal punctum position was achieved in 70% of eyelids, overall, and was highest (88%) with a medial‐based transpositional skin flap. Conclusions : Eyelid retractor repair combined with skin replacement and horizontal lid shortening is an effective procedure for cicatricial ectropion.     

Posterior layer advancement of the lower eyelid retractor in involutional entropion repair

PURPOSE: To examine effectiveness of posterior layer advancement of the lower eyelid retractor in involutional entropion repair. METHODS: Fifty lower eyelids (30 right and 20 left, average patient age 75.5 years) of 43 patients with involutional entropion underwent surgery. All cases were observed for at least 1 year postoperatively. During surgery, after detaching the anterior and posterior surfaces of the lower eyelid retractor, we positively advanced and fixed the posterior layer of the lower eyelid retractor to the tarsus. The anterior layer was used as reinforcement for the posterior layer. When lower eyelid retraction was intraoperatively observed, the suture was changed to fix to a more undercorrected position. RESULTS: Of the 50 patients, only 1, who was the second case operated on, showed recurrent entropion 5 months postoperatively, but following a repeat operation using the same procedure no recurrence was seen in the next 2 years. Three eyelids showed a low degree of ectropion in the early postoperative period, but all improved within 1 month. No postoperative lower eyelid retraction was observed in any patient. CONCLUSIONS: Posterior layer advancement of the lower eyelid retractor is useful for entropion repair.     

Lower eyelid retractor (white-line) advancement to correct tarsal ectropion

Objective

To describe a modification of trans-conjunctival, lower eyelid retractor advancement to correct tarsal ectropion.

Canthus-sparing ectropion repair

PURPOSE: To describe a novel surgical technique for lower eyelid ectropion repair that avoids canthotomy and cantholysis and can be used in combination with external levator repair and/or in combination with blepharoplasty. METHODS: A retrospective analysis of lower eyelid procedures with the use of the canthus-sparing technique between January 1, 1998, and December 31, 1999, was performed. The canthus-sparing approach was used in 198 eyelid procedures for the correction of lower eyelid ectropion. Seventy-four (37.4%) procedures involved the correction of lower eyelid ectropion alone and 25 (12.6%) procedures involved the correction of lower eyelid ectropion during upper eyelid small-incision external levator repair. In these cases, an incision was made lateral to the lateral canthus and a periosteal flap was created at the lateral orbital rim. The inferior crus of the lateral canthal tendon was then attached to this full-thickness elevated periosteum. Twenty (10.1%) procedures involved the correction of ectropion during upper blepharoplasty and 79 (39.9%) procedures involved the correction of ectropion during combined upper eyelid ptosis repair and blepharoplasty. In these cases, the inferior crus of the lateral canthal tendon was attached to a periosteal flap created through the lateral portion of the blepharoplasty incision. RESULTS: The mean age of patients undergoing ectropion repair was 74.3+/-9.3 years (range, 42-93 years). The average duration of symptoms (most commonly tearing and/or ocular irritation) was 20+/-14 months (range, 3-84 months). Recurrences of lower eyelid ectropion or symptoms occurred in 4 (2%) eyelids. The average follow-up interval was 54+/-65 days (range, 3-330 days). CONCLUSIONS: The canthus-sparing approach to ectropion repair promotes a secure adhesion to the lateral orbital wall with minimal violation of normal anatomic structures and relations. It is time-efficient and reduces postoperative morbidity.     

The histopathology of involutional ectropion

Twenty eyelid specimens from patients with involutional ectropion, obtained by full-thickness horizontal shortening procedures, were examined histopathologically by light and electron microscopy and compared with six normal eyelids from exenteration specimens. Paralytic, cicatricial, and congenital ectropions were excluded from the study. The main histopathologic features included: (1) collagen degeneration and elastosis of the tarsal plate; (2) increased amounts of adipose tissue in the distal tarsus and capsulopalpebral fascia; (3) subacute inflammation and epidermidalization of the tarsal conjunctiva; (4) focal degeneration, fibrosis and elastosis of pretarsal orbicularis, and occasionally minimal change in the muscle of Riolan; and (5) arteriosclerosis of the marginal artery. The combination of these histopathologic changes characterize and may contribute to the development of ectropion of the eyelid associated with aging.     

皮肤眼轮匝肌切除联合睫毛外翻褥式缝合矫正儿童下睑倒睫的疗效观察

目的 观察下睑皮肤眼轮匝肌切除联合睫毛外翻褥式缝合矫正术治疗儿童下睑倒睫的远期疗效。设计 回顾性病例系列。研究对象 2013年6月至2016年2月北京同仁医院眼科下睑倒睫患儿200例（400眼）,年龄3~10岁,平均5.56±2.30岁。方法 对200例（400眼）下睑倒睫者适量切除下睑皮肤及眼轮匝肌,睫毛外翻褥式缝合,皮肤连续缝合,部分患者联合灰线切开。术后随访观察6~12个月。主要指标 睫毛位置、畏光、流泪、角膜损伤、眼睑位置形态、有无下睑泪小点外翻、下睑皮肤凹陷性瘢痕、有无明显的下双眼皮。结果 术后患者倒睫全部矫正。200例患者术后随访观察6个月,倒睫无复发。170例患儿随访观察12个月,1例（1眼）倒睫部分复发。术后200例患儿畏光、流泪均消失,200例（380眼）角膜上皮损伤愈合,无下睑内、外翻,无下睑泪小点外翻,无下睑切口处皮肤凹陷性瘢痕,无明显下双眼皮,外观良好。结论 通过对下睑倒睫手术方案的精准设计,皮肤以及眼轮匝肌切除联合睫毛外翻褥式缝合,远期观察倒睫手术效果确切,且外观恢复良好。     

Orbicularis oculi muscle extirpation in a combined procedure for involutional entropion

Many factors are important in the pathophysiology of involutional entropion, including defects of the lower eyelid retractors, canthal tendon laxity, and acquired enophthalmos. The role of the overriding preseptal orbicularis oculi muscle is often ignored in modern techniques of entropion repair. The author describes a technique of extirpation of the preseptal orbicularis oculi muscle combined with repair of the lower eyelid retractors and a lateral tarsal strip procedure for the repair of primary and recurrent involutional entropion. Lateral canthal tendon laxity is recognized in most patients in this age group and must be corrected to avoid postoperative overcorrection and ectropion. Removal of the preseptal muscle had no clinical effect on the lacrimal pump and did not cause any significant cicatricial eyelid abnormalities. This combined procedure has been used in 50 eyelids of 40 patients with excellent functional and cosmetic results. Orbicularis extirpation is not advocated in combination with a marginal rotation procedure.     

Cicatricial ectropion: repair with myocutaneous flaps and canthopexy

BACKGROUND: To evaluate the effectiveness of myocutaneous upper eyelid flaps combined with canthopexy to treat cicatricial lower eyelid ectropion. METHODS: A prospective non-comparative case series undertaken in a private practice setting. Consecutive patients with moderate lower eyelid cicatricial ectropion and upper eyelid dermatochalasis underwent transfer of a bipedicle or monopedicle flap from the upper eyelid combined with canthopexy. The main outcome measures included the occurrence of complications, eyelid position and cosmesis. RESULTS: Sixty-two consecutive cases of cicatricial ectropion repair using myocutaneous flaps and canthopexy. After a mean follow up of 20 months, 58 (93.5%) of the cases had the lower lid punctum facing posterosuperior into the tear lake, showed lid globe apposition and satisfactory eyelid position. There was mild recurrence of cicatricial ectropion in four patients (6.5%). There were no cases of graft failure or granuloma formation. CONCLUSION: The use of a myocutaneous flap from the upper eyelid combined with a canthopexy suspension suture for repair of cicatricial ectropion may offer good eyelid position and function. This technique has the advantage of avoiding full thickness blepharotomy and was associated with a low incidence of early recurrence.     

Congenital ectropion: three case reports and literature review

To report 3 cases of congenital ectropion because of their rarity and confusing classification. Case 1: JPT, 2 days old, male, negro. Left upper eyelid eversion with chemosis was present, passive to mechanic reduction. Compressive occlusion was done with ectropion regression in 48 hours. Case 2: AJL, 6 years old, female, Caucasian, with Down syndrome. The left eye had hyperemia, lagophthalmos and inferior leucoma. She received horizontal shortening (superior and inferior tarsal strip) and skin grafts, and after 2 months the patient did not return. Case 3: GSD, 4 years old, male, Caucasian, with Down syndrome. His signs and treatment were the same as in case 2. According to Picó's classification the first case is classified as grade II due to eyelid eversion during the passage through the birth canal, more frequent in black people. Cases 2 and 3 represent grade III that is due to eyelid skin alteration, and the association with Down syndrome is observed. Treatment for ectropion grade III is always surgical, as it was done in these cases. We do not agree with Picó's classification, the only one found in medline, because there are no articles confirming the existence of grade I (absent tarsus), grade II should be called congenital upper eyelid eversion, grade IV (microphthalmos and orbital cyst) is a disease of the orbit. Grade III refers to true ectropion, because horizontal enlargement of superior and inferior eyelids (megaloblepharon).     

Correction of involutional lower eyelid medial ectropion with transconjunctival approach retractor plication and lateral tarsal strip

AIM: We describe the technique and our results in managing lower eyelid involutional medial ectropion using a combination of lateral tarsal strip to address horizontal eyelid laxity, and transconjunctival inferior retractor plication to address inferior retractor dehiscence. METHODS: Patients with symptoms of epiphora or signs of medial ectropion were offered this procedure. All had the following characteristics: medial lower eyelid eversion, punctal eversion >3 mm, medial canthal tendon laxity <4 mm, significant horizontal eyelid laxity and lacrimal systems that were patent to syringing. RESULTS: A total of 24 eyelids of 17 patients underwent this procedure over a 12-month period. The mean age of the patients was 79.7 years; 11 were male and six were female. The mean follow-up time was 18 months. Two eyes had undergone previous surgery. All patients had restoration of the eyelid margin to the globe and relief of symptoms. No complications were noted. DISCUSSION: These results suggest that excision of posterior lamellar tissue is not necessary for correction of involutional medial ectropion. Transconjunctival plication or reattachment of retractors is easy to perform and allows for the repair of more than the medial portion of the retractors if required.     

60例眼睑全层裂伤的临床特征和急诊手术方法

目的探讨急诊眼睑全层裂伤的病因、临床特点、手术方法及效果。设计回顾性病例系列。研究对象北京同仁医院眼科急诊的60例（60眼）眼睑全层裂伤患者。方法询问病史，详细眼科检查。应用垂直褥式、水平褥式和三缝线缝合法修复眼睑全层裂伤。对伴有泪小管断裂、内外眦韧带离断、眼睑皮肤缺损、眼睑全层缺损、提上睑肌断裂者，还需行泪小管断裂吻合、内外眦韧带复位、提上睑肌断裂缝合复位、皮肤缺损及眼睑缺损修复术。主要指标眼睑形态，日艮睑位置，眼睑运动功能，吻合后的泪小管是否通畅。结果眼睑全层裂伤病因主要是车祸伤、外物击伤、坠落伤、动物咬伤。眼睑裂伤多伴有泪小管断裂、内外眦韧带离断、眼睑皮肤及全层缺损、提上睑肌断裂。急诊手术后随访6～12个月，绝大部分患者术后眼睑外观形态、眼睑闭合以及运动恢复良好，38例（95％）泪小管吻合术后保持通畅。结论车祸伤和外物击伤是急诊眼睑全层裂伤的主要原因，及时、正确、细致地手术处理可使大部分眼睑裂伤在Ⅰ期得到良好的修复，同时也为少部分患者Ⅱ期整复做好准备。     

过睑板下缘连续缝合内固定联合眶隔整复治疗下睑赘皮

目的 评价应用皮肤、眼轮匝肌部分切除＋过睑板下缘连续缝合内固定术,或联合眶隔整复术治疗下睑赘皮的疗效,并分析相关的解剖结构特点.方法 回顾性病例系列研究.回顾分析2006年4月至2010年4月于我院诊断为下睑赘皮并行皮肤、眼轮匝肌部分切除＋过睑板下缘连续缝合内固定术,或联合眶隔整复术的14例患者的临床资料,患者年龄为13～30岁,均为双眼发病.所有患者均采用这种改良术式,其中8例还同时行眶隔整复术.术后随访4个月～4年,平均随访13个月.观察手术疗效：下睑赘皮及倒睫是否完全矫正,症状是否缓解,有无并发症出现及是否复发等.结果 所有患者均行皮肤、眼轮匝肌部分切除＋过睑板下缘连续缝合内固定术,其中8例（57%）术中发现眶隔附着点较高,同时行眶隔整复术.术中发现解剖特点为：所有患者均有下睑皮肤、皮下组织、眼轮匝肌向睑缘部堆积,10例睑缘部眼轮匝肌肥厚,8例眶隔附着点较高.术后27眼（96%）完全矫正,1眼（4%）残留轻度下睑赘皮.所有患者术后均无复发及并发症.结论 皮肤、眼轮匝肌部分切除＋过睑板下缘连续缝合内固定术是治疗下睑赘皮的有效方法,对于眶隔附着点较高者,需同时行眶隔整复术.     

Lateral tarsal strip and quickert sutures for lower eyelid entropion

PURPOSE: To evaluate the long-term outcome of involutional entropion repair by means of a combined procedure of lateral tarsal strip and Quickert everting sutures. METHODS: Noncomparative interventional case series of patients who underwent a combined procedure of lateral tarsal strip and Quickert sutures for treatment of involutional entropion between September 1999 and September 2002. Of 75 patients who underwent surgery, 36 were followed for at least 2 years. At the 2-year clinical examination, patient comfort, complications, recurrence rates, overcorrection, and cosmetic appearance were assessed. RESULTS: The average age of the 36 patients was 76.67 years. There were 5 bilateral cases, for a total of 41 eyelids. Nine eyelids underwent the procedure to correct recurrent entropion. The recurrence rate was 0% at 1 month after surgery, 2 of 41(4.9%) at 6 months, and 5 of 41 (12.2%) at 2 years. The recurrence rate after a primary procedure was 3 of 32 (9.4%), and, after a failed previous procedure, 2 of 9 (22.2%). There were no cases of secondary ectropion, and all patients were happy with their cosmetic appearance. CONCLUSIONS: A combined lateral tarsal strip and Quickert sutures procedure is effective, simple, and addresses all of the factors that contribute to involutional entropion formation, with a good long-term success rate and cosmetic outcome.     

Rotational Flap Repair of Full Thickness Eyelid Defects without a Posterior Lamellar Graft or Flap

Background: To determine the safety and effectiveness of full thickness eyelid reconstructions using a semicircular rotational flap without reconstructing the posterior lamella.

Methods: The charts of all patients undergoing semicircular flap closure of full thickness eyelid defects by one surgeon (JDP) at the Cole Eye Institute between March 2000 and October 2012 were reviewed. Charts were reviewed for patient demographic information, as well as for the size of the defect, the type of flap used, length of follow-up and complications.

Results: Fifty eyelids of 50 patients underwent a semicircular flap repair without posterior lamellar reconstruction during the study period, and 41 charts were available for review. Average patient age was 74 years (range, 40–92 years). Average follow-up was 9.8 months (range, 1–84 months). Average defect size was 19.1?mm (range, 14–30?mm, SD 4.6). Complications included pyogenic granuloma (10 patients, 24.4%), exposure keratopathy (7 patients, 17.1%) lagophthalmos (5 patients, 12.2%), ectropion (6 patients, 14.6%), lateral canthal dystopia (2 cases, 4.9%), eyelid notch (2 cases, 4.9%) and trichiasis (4 cases, 9.8%). Two patients underwent subsequent tarsorrhaphy and one patient underwent ectropion repair. There were no cases of wound dehiscence, diplopia or fornix inadequacy, and the recruited aspect of the eyelid healed well in each case. No case required reconstruction of the eyelid margin or fornix.

Conclusions: Semicircular flap repair of full thickness eyelid defects without flap or graft repair of the posterior lamella results in an adequate fornix and a low rate of secondary surgery.     

Role of the lower lid retractors in involutional ectropion repair

AIM. To outline the role of the lower lid retractors in correction of involutional ectropion. METHODS. Eight eyelids with a tarsal ectropion were included in the study. Clinical clues to help identify weakness of the lower lid retractors were documented. A transconjunctival lower lid retractor reattachment with concommitant correction of horizontal lid laxity and lamellar dissociation was performed. RESULTS. Stable eyelid position was obtained in 7 of the 8 cases. One case had a lateral ectropion due to a wound dehiscence. CONCLUSIONS. This small study helps better define the clinical presentations of retractor weakness and provides evidence of a systematic approach in correcting involutional ectropion.     

A modified posterior approach for upper eyelid retraction

PURPOSE: To describe and review a graded technique for lowering the upper eyelid from a posterior approach, recessing or resecting Müller muscle and levator aponeurosis but leaving a central pillar of Müller muscle intact, occasionally including a temporal tarsorrhaphy or superior tarsal strip where needed, and performing tissue dissection with a hot-wire cautery instrument. METHODS: A 10-year retrospective chart review was performed. Where follow-up was less than 6 months, telephone interviews were conducted to assess patient satisfaction with the procedure. Statistical analysis was performed using an unpaired t test. RESULTS: Ninety-nine patients (161 eyelids, 62 bilateral and 37 unilateral) with a mean age of 47 years (range, 21-82 years) were studied. The mean follow-up period was 61 months. The mean preoperative and postoperative margin reflex distances (MRD1) were 7.3 mm (range, 4.5-10 mm) and 4.3 mm (range, 2-7 mm), respectively. Eighty-nine percent (144/161 eyelids) achieved the target result of an MRD1 of 4 +/- 1 mm after one procedure. Fifteen eyelids (9% of operated eyelids) required a second procedure, and in this group, 2 (13% of the reoperated eyelids) underwent a third procedure. Although bilateral cases were more likely to achieve symmetry (p = 0.0071), 90% of either unilateral or bilateral cases achieved a postoperative MRD1 of 4 +/- 1 mm. Both mild (MRD1 of 5-7 mm) and severe (MRD1 > 7 mm) cases of eyelid retraction achieved similar operative outcomes. In the first 6 months after surgery, complications included undercorrection (8 eyelids), overcorrection (2 eyelids), and pyogenic granuloma (2 eyelids). None had a flattened upper eyelid contour. Late recurrence of retraction was seen in 9 eyelids. Mean operative time was 16 minutes per eyelid. CONCLUSIONS: This technique of lowering the retracted upper eyelid is effective even in severe cases of eyelid retraction. Minimal complications were encountered, and upper eyelid contours were well preserved. The use of hot-wire cautery dissection proved useful in shortening operative time.     

Microscopic findings of lateral tarsal fixation in Asians

PURPOSE: To identify microscopically lateral tarsal fixation in Asians. METHODS: Specimens from 19 postmortem lateral eyelids and orbits of 11 Asians (11 right, 8 left; aged 45-96 years at death) were used. Samples damaged on sectioning and samples without tarsal plates were excluded. The samples were fixed in 10% buffered formalin and examined under a microscope. Two levels of tarsus were observed in the upper and lower eyelids, suggesting the possibility of different means of fixation. The first and second sections, which were incised parallel to the eyelid margin, were obtained at 1 mm and 5 mm from the upper eyelid margin, and at 1 mm and 3 mm from the lower eyelid margin. The sections were stained with Masson trichrome. RESULTS: The first sections of all upper eyelids and those of the lower eyelids except one showed tarsal fixation by both the lateral rectus capsulopalpebral fascia (lr-CPF) and the tendon-ligament complex of the lateral canthal tendon (LCT), which in several cases received the muscle of Riolan. The second sections of all upper eyelids showed fixation by the lr-CPF and the ligamentous part of the LCT. The second sections of the lower eyelids were mostly similar to the second sections of upper eyelids, though some showed only ligamentous fixation. The lr-CPF in all cases included a small amount of smooth muscle fibers. CONCLUSIONS: The lateral aspect of the tarsus is supported by the lr-CPF and the LCT, which in some cases includes the muscle of Riolan.