The historical evaluation of a brow ptosis patient is key to determining the underlying etiology.

• History of present illness should be focused on the onset and progression of symptoms. A long term onset in an older patient clues the provider into an age-related case. In contrast, patients with more rapid onset may be suffering from Bell palsy, trauma, neoplasm, or other more unusual causes. A waxing and waning course with accompanying fatigability could be clues for myotonic dystrophy, myasthenia gravis, or oculopharyngeal dystrophy. 
• The medical history should specifically evaluate for past instances of facial paralysis of any etiology, even cases long in the past.
• Chemotherapy and radiation should be asked about, as they can speed cutaneous and soft tissue aging.
• The surgical/procedural history must reveal all surgeries in the area of the brow and along the course of the facial nerve, including any neuro-otologic or neurosurgical procedures. Botulinum toxin injections must be inquired about. 
• The social history should reveal sun exposure, smoking, and drug use as they can all speed involutional changes.

The physical exam should follow a formulaic, stepwise approach that is generalizable to all periorbital aging.[10]

• Neutral brow position should be evaluated by having the patient close his or her eyes and relax the facial muscles, then open the eyes as gently as possible without raising the brows.
• Brow versus lid pathology should be differentiated via manual elevation of the brow to the neutral position. A lid that is still ptotic after brow elevation indicates true blepharoptosis, rather than pseudoptosis caused by a drooping brow.
• Blepharoptosis should be thoroughly evaluated. Margin-reflex distance (MRD) is recorded. This is the distance measured from the corneal light reflex to the upper lid margin (MRD-1) or lower lid margin (MRD-2). MRD-1 less than 2-3 mm is indicative of blepharoptosis. The distance also needs to be measured between the upper eyelid margin and the superior palpebral crease. More than 8-10 mm often indicates blepharoptosis due to levator aponeurosis dehiscence. Brow asymmetry must also be noted if present. An asymmetric brow with symmetric eyelids may be masking ptosis on the side of the elevated brow due to excessive frontalis contraction in an attempt to compensate for a ptotic eyelid. Finally, the patient must be evaluated for the Hering phenomenon. If the elevation of a ptotic lid - or the lid on the side of the elevated brow - produces drooping of the contralateral upper eyelid, the patient may have bilateral but asymmetric blepharoptosis. Brow height asymmetry is also commonly caused by hemifacial microsomia, more frequently on the right than on the left.
• While not directly applicable to the evaluation of brow ptosis, the points mentioned here are essential to a thorough periorbital examination: festoons and fat pseudoherniation should be evaluated with digital pressure on the globe while visualizing the upper and lower lids. The former will not enlarge, but the latter will. Festoons will also contract with effortful eye closure. Lower lid laxity should be evaluated via the snap test. This is performed by distracting the lid from the globe, then releasing and observing lid recoil, which should take no longer than 2 seconds and should occur without the patient blinking. The lower eyelid vector should be evaluated via observation of the relationship between the cornea and cheek with the patient in the Frankfort horizontal position. If the cornea is anterior to the cheek skin at the infraorbital rim, the vector is negative. This is associated with aging and increased risk of ectropion if lower lid blepharoplasty is performed. Finally, tear production should be evaluated via the Schirmer test. Filter paper is inserted into the fornix of the lower eyelid; if there is less than 10 mm of dampness after 5 minutes, tear production is not adequate, and the surgeon must adjust the surgical plan accordingly. 
• The hairline position and shape of the forehead must be visually evaluated to inform the surgeon’s choice of operative approach.
• A thorough cranial nerve exam should be carried out, especially if damage to the facial nerve is suspected.

Evaluation of brow ptosis outside of thorough history and physical is rarely necessary. However, there are some cases in which imaging and labs are beneficial or even diagnostic. Myogenic causes have lab tests specific to them; for example, suspected myasthenia gravis may be diagnosed via serologic testing for acetylcholine receptor antibodies.[14] Brow ptosis caused by neoplasm will need a full workup of the mass. These evaluations vary widely based on the suspected type of neoplasm, including anything from shave biopsy to MRI to PET scanning.

The treatment of brow ptosis [15] is dependent on brow morphology, ptosis etiology, severity, and, most importantly, patient goals. Surgical management is required for the resolution of age-related causes. It is also indicated in some traumatic, neoplastic, or iatrogenic causes. Those surgeries may include nerve decompression, removal of neoplasm, or nerve reconstruction, and are outside the scope of the current discussion. More common procedures used to treat brow ptosis are discussed below. Many of these procedures are combined with other rejuvenation procedures such as upper blepharoplasty, botox injection, or skin resurfacing.

The endoscopic brow lift also called the endobrow procedure, is the most common approach.[16] Dissection is carried forward from the median, paramedian, and temporal incisions in the subperiosteal plane (within the central forehead) and a plane along the fascia of the temporalis muscle (laterally) until the periosteum around the superior and lateral orbit is released at the arcus marginalis. Then the periosteum is lifted and fixated to the skull; this is often accomplished with resorbable implants, but may also be performed with screws and staples or a drill and suture. The endoscopic brow lift is best suited for patients with low or average brow height, defined as six or fewer centimeters from the brow to the hairline, and those without significant curvature or bossing of the forehead. A major benefit of this procedure is that it can address glabellar rhytides, a common comorbidity of brow ptosis, through the division of the corrugator supercilii or procerus muscles. Some limitations include only about 5 mm of lift, risk of damage to the frontal branch of the facial nerve which would exacerbate brow ptosis, risk of damage to the supratrochlear and supraorbital nerves that would cause forehead numbness, and difficulty in correcting brow asymmetry.

Open coronal approaches are named based on the location of the initial incision. Pretrichial incisions are placed at or just in front of the hairline, while trichophytic incisions are hidden within the hairline; the classic coronal incision passes directly over the vertex of the scalp. Dissection is carried forward in the subgaleal plane until diving subperiosteally 1-2 cm superior to the orbital rim. The flap is elevated, the excess skin and soft tissue are excised as necessary, and the incision is closed. These procedures allow for better visualization of critical structures like the frontal branch of the facial nerve and can achieve a higher lift than the endoscopic option. However, they result in significant scars that may be revealed by balding and more commonly cause minor complications like forehead numbness, pruritus, and alopecia.

The direct brow lift is performed through an incision just above the hair-bearing brow. Excess skin and soft tissue are excised to create a considerable amount of lift with a relatively minor procedure, one that can easily be done in the clinic under local anesthesia. This procedure is the most effective option for heavy lateral hooding and is the most straightforward procedure with which to correct brow asymmetry. Its drawbacks include the risk of visible scarring and an increased chance of excessive elevation that may result in a surprised look.

For significant brow asymmetry, particularly for patients with facial paralysis and very dense soft tissues, unilateral suture suspension of the ptotic brow to a titanium miniplate fixated to the frontal bone at the level of the hairline may be effective.  As a side benefit, the sutures can potentially be tightened under local anesthesia in the future if the brow ptosis recurs or worsens.

The transblepharoplasty browpexy is a way to combine treatment of upper lid dermatochalasis or blepharoptosis with the treatment of brow ptosis. These conditions are often comorbid, so this approach is becoming more common. An upper eyelid blepharoplasty is performed first, then dissection is carried superiorly, along the orbital septum, until the pericranium above the supraorbital rim is reached. The periosteum can then be used as an anchor to suspend the brow from its deep surface.

The mid-forehead brow lift is mostly a procedure of historical interest, in which an incision is hidden within a deep, transverse forehead rhytid. The excess skin and soft tissue are excised, and the incision is closed like the direct brow lift. It has been largely abandoned because the scars are very hard to hide, and other options allow for a similar amount of lift. 

Nonsurgical treatment may be pursued in particular cases. Botox injections effectively treat spastic brow ptosis or even elevate the brow slightly by weakening the depressor supercilii muscle; more systemic etiologies like myasthenia gravis need specialized medical therapy.

Brow ptosis is a fairly straightforward and well-defined diagnosis but may be confused with or obscured by other periorbital pathology. Asymmetric brow ptosis can seem like unilateral pathology unless a thorough physical exam reveals that the more ptotic side was masking the appearance of the less ptotic side. Severe dermatochalasis or blepharoptosis may distract the physician from identifying concomitant brow ptosis. A thorough history and physical examination will reveal whether a patient’s brow ptosis is age-related, traumatic, myogenic, spasm-induced, infectious, neoplastic, or iatrogenic.

Prognosis is highly dependent on etiology and the patients' primary concerns. For those who are mainly focused on the visual field deficits caused by their ptotic brows, full resolution and patient satisfaction can usually be achieved. [17] Patients whose concerns are primarily cosmetic have higher dissatisfaction rates. Patients with non-age-related etiologies have more varied prognoses.

Brow ptosis itself rarely progresses to more serious pathology. Its most notable sequela is visual field obstruction, progressing from lateral to medial. 

Brow ptosis correction surgery complications include patient dissatisfaction (7.4%), numbness of the forehead due to supratrochlear and supraorbital nerve damage (5.5%), alopecia (2.8%), and brow asymmetry (1.7%).[8] 

Nonsurgical brow rejuvenation complications are very rare. The most common complication of Botox treatment is periorbital bruising in 1.7% of patients.

Patients should be educated to their desired level of detail on the pathophysiology of the cause of the brow ptosis. Once sufficient understanding of the pathology is achieved, surgical and nonsurgical treatment options should be explained in order to inform a decision. A thorough discussion of both common and rare complications of the chosen treatment method is required.

Brow ptosis is a relatively common problem, but one that is often misdiagnosed or overlooked due to more apparent upper eyelid pathologies. Patients almost always first present to their primary care providers, who must refer to the appropriate facial plastics, general plastics, or oculoplastics specialist for definitive treatment. Once patients are directed to the correct subspecialist, close coordination among nurses, physicians, case managers, and others in direct contact with the patient is key to a timely and satisfactory outcome. Cases that are not age-related may require further consultation with neurosurgery, neurology, infectious disease, rheumatology, or other specialties.

Intraoperatively, a support staff made up of specialty-trained nurses who are familiar with the equipment and selected procedure in conjunction with a properly subspecialized and experienced surgeon is imperative to a safe and effective procedure. [Level 5]