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THS is usually diagnosed via exclusion, and as such a vast amount of laboratory tests are required to rule out other causes of the patient's symptoms. These tests include a complete blood count, thyroid function tests and serum protein electrophoresis. Studies of cerebrospinal fluid may also be beneficial in distinguishing between THS and conditions with similar signs and symptoms.
MRI scans of the brain and orbit with and without contrast, magnetic resonance angiography or digital subtraction angiography and a CT scan of the brain and orbit with and without contrast may all be useful in detecting inflammatory changes in the cavernous sinus, superior orbital fissure and/or orbital apex. Inflammatory change of the orbit on cross sectional imaging in the absence of cranial nerve palsy is described by the more benign and general nomenclature of orbital pseudotumor.
Sometimes a biopsy may need to be obtained to confirm the diagnosis, as it is useful in ruling out a neoplasm.
Differentials to consider when diagnosing THS include craniopharyngioma, migraine and meningioma.
Treatment of THS includes immunosuppressives such as corticosteroids (often prednisolone) or steroid-sparing agents (such as methotrexate or azathioprine).
Radiotherapy has also been proposed.
Though outwardly similar to cluster headaches, chronic paroxysmal hemicrania is rather different, and the two headaches are not a subset of one or the other. Key differences include:
- Different gender distributions – CPH is more common in women than men, with opposite occurring with cluster headaches.
- CPH attacks occur more frequently, but are shorter.
- Individuals with CPH are far more responsive to indomethacin than individuals with cluster headaches.
- CPH attacks can be provoked by neck movement.
- In a study conducted by Sjaastad, heating a patient's body will cause the painful side of the forehead to sweat more in CPH patients, while there will be less sweating on that side for those suffering from cluster headaches.
A ten-patient study conducted by Pareja et al. found that all patients diagnosed with CPH were responsive to indomethacin and were able to completely control their symptoms. Doses of the drug ranged from 25 mg per day to 150 mg per day with a median dose of 75 mg per 24-hour period.
Almost all cases of CPH respond positively and effectively to indometacin, but as much as 25 percent of patients discontinued use of the drug due to adverse side effects, namely complications in the gastrointestinal tract.
According to a case study by Milanlioglu et al., 100mg of lamotrigine, an antiepileptic drug, administered twice daily alleviated all painful symptoms. No side effects were noted after two months of treatment. Dosage of lamotrigine was decreased to 50mg a day after the first two months, and no symptoms or side-effects were recorded after a three-month followup.
Use of topiramate has also been found to be an effective treatment for CPH, but cluster headache medications have been found to have little effect.
Three tests are useful in confirming the presence and severity of Horner syndrome:
- Cocaine drop test: Cocaine eyedrops block the reuptake of post-ganglionic norepinephrine resulting in the dilation of a normal pupil from retention of norepinephrine in the synapse. However, in Horner's syndrome the lack of norepinephrine in the synaptic cleft causes mydriatic failure. A more recently introduced approach that is more dependable and obviates the difficulties in obtaining cocaine is to apply the alpha-agonist apraclonidine to both eyes and observe the increased mydriatic effect (due to hypersensitivity) on the affected side of Horner syndrome (the opposite effect to what the cocaine test would produce in the presence of Horner's).
- Paredrine test: This test helps to localize the cause of the miosis. If the third order neuron (the last of three neurons in the pathway which ultimately discharges norepinephrine into the synaptic cleft) is intact, then the amphetamine causes neurotransmitter vesicle release, thus releasing norepinephrine into the synaptic cleft and resulting in robust mydriasis of the affected pupil. If the lesion itself is of the third order neuron, then the amphetamine will have no effect and the pupil remains constricted. There is no pharmacological test to differentiate between a first and second order neuron lesion.
- Dilation lag test
It is important to distinguish the ptosis caused by Horner's syndrome from the ptosis caused by a lesion to the oculomotor nerve. In the former, the ptosis occurs with a constricted pupil (due to a loss of sympathetics to the eye), whereas in the latter, the ptosis occurs with a dilated pupil (due to a loss of innervation to the sphincter pupillae). In a clinical setting, these two ptoses are fairly easy to distinguish. In addition to the blown pupil in a CNIII (oculomotor nerve) lesion, this ptosis is much more severe, occasionally occluding the whole eye. The ptosis of Horner syndrome can be quite mild or barely noticeable (partial ptosis).
When anisocoria occurs and the examiner is unsure whether the abnormal pupil is the constricted or dilated one, if a one-sided ptosis is present then the abnormally sized pupil can be presumed to be on the side of the ptosis.
The most common causes in young children are birth trauma and a type of cancer called neuroblastoma. The cause of about a third of cases in children is unknown.
The best imaging modality for idiopathic orbital inflammatory disease is contrast-enhanced thin section magnetic resonance with fat suppression. The best diagnostic clue is a poorly marginated, mass-like enhancing soft tissue involving any area of the orbit.
Overall, radiographic features for idiopathic orbital inflammatory syndrome vary widely. They include inflammation of the extraocular muscles (myositis) with tendinous involvement, orbital fat stranding, lacrimal gland inflammation and enlargement (dacryoadenitis), involvement of the optic sheath complex, uvea, and sclera, a focal intraorbital mass or even diffuse orbital involvement. Bone destruction and intracranial extension is rare, but has been reported. Depending on the area of involvement, IOI may be categorized as:
- Myositic
- Lacrimal
- Anterior – Involvement of the globe, retrobulbar orbit
- Diffuse – Multifocal intraconal involvement with or without an extraconal component
- Apical – Involving the orbital apex and with intracranial involvement
Tolosa–Hunt syndrome is a variant of orbital pseudotumor in which there is extension into the cavernous sinus through the superior orbital fissure. Another disease variant is Sclerosing pseudotumor, which more often presents bilaterally and may extend into the sinuses.
CT findings
In non-enhanced CT one may observe a lacrimal, extra-ocular muscle, or other orbital mass. It may be focal or infiltrative and will have poorly circumscribed soft tissue. In contrast-enhanced CT there is moderate diffuse irregularity and enhancement of the involved structures. A dynamic CT will show an attenuation increase in the late phase, contrary to lymphoma where there is an attenuation decrease. Bone CT will rarely show bone remodeling or erosion, as mentioned above.
MR findings
On MR examination there is hypointensity in T1 weighted imaging (WI), particularly in sclerosing disease. T1WI with contrast will show moderate to marked diffuse irregularity and enhancement of involved structures. T2 weighted imaging with fat suppression will show iso- or slight hyperintensity compared to muscle. There is also decreased signal intensity compared to most orbital lesions due to cellular infiltrate and fibrosis. In chronic disease or sclerosing variant, T2WI with FS will show hypointensity (due to fibrosis). Findings on STIR (Short T1 Inversion Recovery) are similar to those on T2WI FS. In Tolosa–Hunt syndrome, findings include enhancement and fullness of the anterior cavernous sinus and superior orbital fissure in T1WI with contrast, while MRA may show narrowing of cavernous sinus internal carotid artery (ICA).
Ultrasonographic findings
On grayscale ultrasound there is reduced reflectivity, regular internal echoes, and weak attenuation, in a way, similar to lymphoproliferative lesions.
Diagnosis is generally made by magnetic resonance imaging (MRI), particularly using a specific imaging technique known as a gradient-echo sequence MRI, which can unmask small or punctate lesions that may otherwise remain undetected. These lesions are also more conspicuous on FLAIR imaging compared to standard T2 weighing. FLAIR imaging is different from gradient sequences. Rather, it is similar to T2 weighing but suppresses free-flowing fluid signal. Sometimes quiescent CCMs can be revealed as incidental findings during MRI exams ordered for other reasons. Many cavernous hemangiomas are detected "accidentally" during MRIs searching for other pathologies. These "incidentalomas" are generally asymptomatic. In the case of hemorrhage, however, a CT scan is more efficient at showing new blood than an MRI, and when brain hemorrhage is suspected, a CT scan may be ordered first, followed by an MRI to confirm the type of lesion that has bled.
Sometimes the lesion appearance imaged by MRI remains inconclusive. Consequently neurosurgeons will order a cerebral angiogram or magnetic resonance angiogram (MRA). Since CCMs are low flow lesions (they are hooked into the venous side of the circulatory system), they will be angiographically occult (invisible). If a lesion is discernible via angiogram in the same location as in the MRI, then an arteriovenous malformation (AVM) becomes the primary concern.
Corticosteroids remain the main treatment modality for IOI. There is usually a dramatic response to this treatment and is often viewed as pathognomonic for this disease. Although response is usually quick, many agree that corticosteroids should be continued on a tapering basis to avoid breakthrough inflammation.
Although many respond to corticosteroid treatment alone, there are several cases in which adjuvant therapy is needed. While many alternatives are available, there is no particular well-established protocol to guide adjuvant therapy. Among the available options there is: surgery, alternative corticosteroid delivery, radiation therapy, non-steroidal anti-inflammatory drugs, cytotoxic agents (chlorambucil, cyclophosphamide), corticosteroid sparing immunosuppressants (methotrexate, cyclosporine, azathioprine), IV immune-globin, plasmapheresis, and biologic treatments (such as TNF-α inhibitors).
Because this genetic anomaly is genetically linked, genetic counseling may be the only way to decrease occurrences of Cherubism. The lack of severe symptoms in the parents may be the cause of failure in recognizing the disorder. The optimal time to be tested for mutations is prior to having children. The disorder results from a genetic mutation, and this gene has been found to spontaneously mutate. Therefore, there may be no prevention techniques available.
Trochleitis is diagnosed based on three criteria: 1) demonstration of inflammation of superior oblique tendon/ trochlea region, 2) periorbital pain and tenderness to palpation in the area of the sore trochlea, and 3) worsening of pain on attempted vertical eye movement, particularly with adduction of the eye. It is important to identify trochleitis because it is a treatable condition and the patient can benefit much from pain relief. Treatment consists of a single injection of corticosteroids to the affected peritrochlear region. A specific "cocktail" consisting of 0.5 ml of depomedrol (80 mg/ml) and 0.5 ml of 2% lidocaine can be injected into the trochlea; immediate relief due to the effects of the local anesthetic indicates successful placement. However, great care must be taken as the injection is in the region of several arteries, veins and nerves. The needle should not be too small (so as not to penetrate tiny structures), the surgeon should draw back on the syringe (to ensure not have pierced a vessel), the lidocaine should not contain epinephrine (which could cause vasospasm), and the pressure of the injection must always be controlled. Only a limited number of injections can be made as they would otherwise lead to muscle atrophy. Diagnosis can be confirmed by response to this treatment; pain and swelling are expected to disappear in 48–72 hours. Some patients experience recurrence of trochleitis.
Dacryoadenitis can be diagnosed by examination of the eyes and lids. Special tests such as a CT scan may be required to search for the cause. Sometimes biopsy will be needed to be sure that a tumor of the lacrimal gland is not present.
The extent of inflammation that can occur in IgG4-ROD is well demonstrated on magnetic resonance imaging (MRI).
Infraorbital nerve enlargement (IONE) is considered to be a particularly suspicious sign of IgG4-ROD, but seems to occur only when inflammation is in direct contact with the infraorbital canal. IONE is defined as the infraorbital nerve diameter being greater than the optic nerve diameter in the coronal plane.
If the cause of dacryoadenitis is a viral condition such as mumps, simple rest and warm compresses may be all that is needed. For other causes, the treatment is specific to the causative disease.
IgG4-related ophthalmic disease (IgG4-ROD) is the recommended term to describe orbital (eye socket) manifestations of the systemic condition IgG4-related disease, which is characterised by infiltration of lymphocytes and plasma cells and subsequent fibrosis in involved structures. It can involve one or more of the orbital structures.
Frequently involved structures include the lacrimal glands, extraocular muscles, infraorbital nerve, supraorbital nerve and eyelids. It has also been speculated that ligneous conjunctivitis may be a manifestation of IgG4-related disease (IgG4-RD).
As is the case with other manifestations of IgG4-related disease, a prompt response to steroid therapy is a characteristic feature of IgG4-ROD in most cases, unless significant fibrosis has already occurred.
Other disorders can mimic the appearance of nasal polyps and should be considered if a mass is seen on exam. Examples include encephalocele, glioma, inverted papilloma, and cancer. Early biopsy is recommended for unilateral nasal polyps to rule out more serious conditions such as cancer, inverted papilloma, or fungal sinusitis.
CT scan can show the full extent of the polyp, which may not be fully appreciated with physical examination alone. Imaging is also required for planning surgical treatment. On a CT scan, a nasal polyp generally has an attenuation of 10–18 Hounsfield units, which is similar to that of mucus. Nasal polyps may have calcification.
As diagnostic criteria have been indecisive and its pathophysiology remains unclear, no permanent cure is available. Antiepileptic medications (membrane-stabilizing drugs) such as pregabalin, gabapentin, topiramate, and lamotrigine improve symptoms, but there is no effective permanent or long-term treatment for SUNCT.
However, a few short-term treatments are available and can relieve and possibly prevent some symptoms of attacks.
Lamotrigine exhibits some long-term prevention and reduction in many patients; however, titration of dose is difficult due to adverse skin reactions.
Topiramate also has preventive effects but it is accompanied by a high risk of severe side-effects for patients with a history of kidney stones, glaucoma, depression, or low body weight.
Intravenous lidocaine can abolish symptoms during its administration, or reduce frequency and duration of attacks. However, administration of intravenous lidocaine requires careful monitoring of ECG and blood pressure.
Methylprednisolone therapy shows some promise in short-term prevention of attacks, even though its mechanism of action is yet to be discovered.
The calcium channel blocker verapamil is reported to be useful in alleviating symptoms (lower frequency and duration of attacks), even though some patients experience worsened symptoms.
Various medications that are often used in other headache syndromes such as nonsteroidal anti-inflammatory drugs, acetaminophen, tricyclic antidepressants, calcium channel antagonists do not relieve the symptoms of SUNCT.
There have been attempts to alter oxygen supply during attacks to alleviate the symptoms since some of the headaches are caused by decreased oxygen supply; however, elevated blood oxygen level did not affect the symptoms.
Researchers now focus on the administration of various combination of medications and therapies to treat symptoms of SUNCT.
If binocular vision is present and head position is correct, treatment is not obligatory.
Treatment is required for: visual symptoms, strabismus, or incorrect head position.
Acquired cases that have active inflammation of the superior oblique tendon may benefit from local corticosteroid injections in the region of the trochlea.
The goal of surgery is to restore free ocular rotations. Various surgical techniques have been used:
- Harold Brown advocated that the superior oblique tendon be stripped. A procedure named sheathotomy. The results of such a procedure are frequently unsatisfactory because of reformation of scar tissue.
- Tenotomy of the superior oblique tendon (with or with out a tendon spacer) has also been advocated. This has the disadvantage that it frequently produces a superior oblique paresis.
- Weakening of the inferior oblique muscle of the affected eye may be needed to compensate for iatrogenic fourth nerve palsy.
During surgery, a traction test is repeated until the eye rotations are free and the eye is anchored in an elevated adducted position for about two weeks after the surgery. This maneuver is intended to prevent the reformation of scar tissue in the same places. Normalization of head position may occur but restoration of full motility is seldom achieved. A second procedure may be required.
The majority of patients remain symptom free and able to maintain binocularity with only a slight face turn. Amblyopia is uncommon and, where present, rarely dense. This can be treated with occlusion, and any refractive error can also be corrected.
Duane syndrome cannot be cured, as the "missing" cranial nerve cannot be replaced, and traditionally there has been no expectation that surgery will result in any increase in the range of eye movement. Surgical intervention, therefore, has only been recommended where the patient is unable to maintain binocularity, where they are experiencing symptoms, or where they are forced to adopt a cosmetically unsightly or uncomfortable head posture in order to maintain binocularity. The aims of surgery are to place the eye in a more central position and, thus, place the field of binocularity more centrally also, and to overcome or reduce the need for the adoption of an abnormal head posture. Occasionally, surgery is not needed during childhood, but becomes appropriate later in life, as head position changes (presumably due to progressive muscle contracture).
Surgical approaches include:
- Medial rectus recession in the involved eye or both eyes. By weakening the medial rectus muscles this procedure improves the crossed-eye appearance but does not improve outward eye movements (abductions).
- Morad et al. showed improved abduction after modest unilateral medial rectus recession and lateral rectus resection in a subgroup of patients with mild eye retraction and good adduction before surgery.
- Lateral transposition of the vertical muscles described by Rosenbaum has been shown to improve range of movement of the eye. The surgical procedure produces 40-65 degrees of binocular field. Orbital wall fixation of the lateral rectus muscle (muscle is disinserted and reattached to lateral orbital wall) is recommended an effective method to inactivate a lateral rectus muscle in cases of marked anomalous innervation and severe cocontraction.
The chemical imbalance is usually diagnosed when dental abnormalities are found. These abnormalities include premature deciduous teeth and abnormal growth of permanent teeth due to displacement by cysts and lesions. The only definite way to correctly diagnose the condition is by sequence analysis of the SH3BP2 gene. The gene has been found to have missense mutation in exon 9. Initial study of the patient is usually conducted using x-ray and CT scans. Neurofibromatosis may resemble Cherubism and may accompany the condition. Genetic testing is the final diagnosis tool.
CBC, ESR, blood cultures, and sinus cultures help establish and identify an infectious primary source. Lumbar puncture is necessary to rule out meningitis.
Sinus films are helpful in the diagnosis of sphenoid sinusitis. Opacification, sclerosis, and air-fluid levels are typical findings. Contrast-enhanced CT scan may reveal underlying sinusitis, thickening of the superior ophthalmic vein, and irregular filling defects within the cavernous sinus; however, findings may be normal early in the disease course.
A MRI using flow parameters and an MR venogram are more sensitive than a CT scan, and are the imaging studies of choice to diagnose cavernous sinus thrombosis. Findings may include deformity of the internal carotid artery within the cavernous sinus, and an obvious signal hyperintensity within thrombosed vascular sinuses on all pulse sequences.
Cerebral angiography can be performed, but it is invasive and not very sensitive. Orbital venography is difficult to perform, but it is excellent in diagnosing occlusion of the cavernous sinus.
Gradient-Echo T2WI magnetic resonance imaging (MRI) is most sensitive method for diagnosing cavernous hemangiomas. MRI is such a powerful tool for diagnosis, it has led to an increase in diagnosis of cavernous hemangiomas since the technology's advent in the 1980s. The radiographic appearance is most commonly described as "popcorn" or "mulberry"-shaped. Computed tomography (CT) scanning is not a sensitive or specific method for diagnosing cavernous hemangiomas. Angiography is typically not necessary, unless it is required to rule out other diagnoses. Additionally, biopsies can be obtained from tumor tissue for examination under a microscope. It is essential to diagnose cavernous hemangioma because treatments for this benign tumor are less aggressive than that of cancerous tumors, such as angiosarcoma. However, since MRI appearance is practically pathognomonic, biopsy is rarely needed for verification.
Most patients are diagnosed by the age of 10 years and Duane's is more common in girls (60 percent of the cases) than boys (40 percent of the cases). A French study reports that this syndrome accounts for 1.9% of the population of strabismic patients, 53.5% of patients are female, is unilateral in 78% of cases, and the left eye (71.9%) is affected more frequently than the right. Around 10–20% of cases are familial; these are more likely to be bilateral than non-familial Duane syndrome. Duane syndrome has no particular race predilection.