Results of Long-Term Follow-Up Observations of Blepharoptosis Correction Using the Palmaris Longus Tendon

The materials used for the frontalis sling procedure include artificial materials such as prolene, a silicone sling, supramid suture, braided polyester, expanded polytetrafluoroethylene (Gore-Tex), and autogenous tensor fascia lata and palmaris longus tendon. In addition, freeze-dried tensor fascia lata, which is a treated tensor fascia lata of humans, can also be used. Nevertheless, there are reports of poor long-term results in cases treated using the tensor fascia lata. Wilson and Johnson [5] went so far as to state that half the procedures in which the tensor fascia lata was used failed 8–9 years after surgery. However, there were significantly different results between the autogenous fascia lata and lyophilized fascia lata. Wassermann et al. [6] reported recurrence rates of 4.2% with the autogenous fascia lata and 51.4% with the lyophilized fascia lata. On the other hand, the palmaris longus tendon might be used in children under the age of 3 years and would be an autogenous tissue with less recurrence after surgery. Wong et al. [7] examined 14 patients and 15 eyelids and reported that there was no recurrence after surgery using the palmaris longus tendon during a mean follow-up period of 7.8 years. Therefore, the palmaris longus tendon, with its advantage of being an autogenous tissue and having long-term endurance after surgery, might be an ideal material for blepharoptosis correction compared with the autogenous tensor fascia lata.

The problem in using the palmaris longus tendon is that there are many anatomical variations. Reimann et al. [8] reported in a study of 1600 cases that approximately 21.8% of patients had anatomical abnormalities, the most common being an absence of the palmaris longus tendon (in up 12.8% of cases). Lee [9] reported the bilateral and unilateral existence of the palmaris longus tendon in 70% and 85%, respectively. On the other hand, Won et. al. [10], in a study of 1000 patients, reported the bilateral absence of the palmaris longus tendon in 11 patients (1.1%) and unilateral absence in 32 (3.2%). A study in China reported that the incidence of bilateral and unilateral absence was 1.2% and 3.3%, respectively [11]. This means that there are significant anatomical variations between Asians and Caucasians with respect to the palmaris longus tendon. Cases where the palmaris longus tendon is missing often have other anatomical abnormalities. A typical example would be the plantaris tendon [12]. However, the plantaris tendon has relatively no association with the absence of the flexor digitorum superficialis of the fifth finger [13]. Other than that, the variation of the superficial palmar arch or cases in which the muscle and tendon parts are switched and the muscle part exists distally might be the cause of carpal tunnel syndrome [14, 15]. In addition, it should be noted that there could be a multitude of anatomical variations that need to be considered before surgery. Reimann et al. [8] reported that more females lacked the palmaris longus tendon on the left side. However, recent studies showed that there were no significant differences in the presence of the palmaris longus tendon between genders or between the left and right sides [10‐12]. The mean length of the palmaris longus tendon in Asians is 124 mm for males and 108 mm for females, and the mean widths are 45 mm for males and 40 mm for females [16]. There are many methods for verifying the introduction of the palmaris longus tendon, including the “two finger” sign, “finger fan out” sign, “closed fist” sign, “lotus” sign, and “flexion of the wrist against resistance.” All these methods examine for presence of the palmaris longus tendon [17].

The disadvantage of the eyelid bulging out was minimized using a one-half to one-third portion of the palmaris longus tendon instead of the entire tendon. In particular, Asians do not like the baseline of the double-folded eyelid bulging out, and it is best to perform surgery using a minimum thickness palmaris longus tendon. A complete resection of the palmaris longus tendon does not lead to functional abnormalities such as a reduction in finger gripping and grabbing power. Nevertheless, only a part of the palmaris longus tendon was used to prevent wasting the tendon [18].

The methods for fixing the palmaris longus tendon differ between authors. First, Kurihara et al. [3] attempted to achieve symmetry by dividing one strip into three. Chung et al. later utilized the same method [19]. Typical fixation methods using the existing tensor fascia lata include the Fox method and the Crawford method. Later, many modified approaches were introduced, including one triangle (Fox variation), two triangles (Crawford variation), and pentagonal and rectangular forms. This study used a pentagonal form, which is a modified Fox method that allows a firmer fixation than the triangle form that uses one fixing point. The pentagonal form uses two fixation points and reduces the incidence of recurrence. With respect to suturing the palmaris longus tendon onto the eyelid, distortion of the eyelid shape was minimized by allowing five chances to adjust the eyelid: (1) when suturing the palmaris longus tendon onto the tarsal plate, (2, 3) when suturing it to the eyebrow area (left and right), (4) when tying up two strips of the palmaris longus tendon into one, and (5) when fixing it onto the frontalis muscle. Fixation in the eyebrow area would be carried out into the subfollicular layer. According to Hwang et al. [20] the reason could be that the layer of the frontalis muscle would extend to the inner area of the eyebrow, to the upper edge of the eyebrow centrally, and to the area 0.5 cm below the upper edge of the eyebrow laterally. Therefore, fixations of the layer of the frontalis muscle onto the eyebrow can have the effect of suturing onto the frontalis muscle itself. For target locations of the edge of the eyelid, an excess of 1 mm on one side compared with the opposite side was corrected in unilateral eyelid surgery while the level of lagophthalmos was considered for the area located 1–2 mm above the corneal limbus in bilateral eyelid surgery before undertaking such corrective surgery. This level was lower than the area 1 mm above the corneal limbus targeted by Lam et al. [2]. This means that postoperative complications such as exposure keratitis could last a long time if a surgeon positions the palmaris longus tendon into an area considered to be “good” in Manners et al. [21] postoperative assessment. Therefore, it is believed that the incidence of complications can be reduced and an adequate field of view and good aesthetic outcome can be provided by securing a sufficient field of view and positioning the fixation in an area 1 mm below the corneal limbus [21]. To reduce the probability of exposure keratitis, the patients were asked to administer an artificial tear solution or ointment before bedtime for a minimum of 6 months to 1 year.

A preoperative plan might be the most important index for determining the suitability of surgery. Achieving left and right symmetry during surgery is often very difficult because of local anesthesia or hematoma. In such cases, it would be best to confirm the difference between the left and right sides in a lid lag, and at the same time the surgeon should perform surgery based on the preoperative plan. Even in long-term follow-up observations after surgery, the position of the eyelid edge allows verification of the visual field and maintenance of the location that is not associated with an excessive or underestimated correction. This article reports this method based on the idea that the postoperative MRD1 is 3.1 mm and a correction of severe blepharoptosis using the palmaris longus tendon can provide excellent long-term results, bilateral symmetry, and less recurrence.