There are no specific radiological tests for SCTC verification. However these tests might be useful for identification of tumor borders and in planning of surgery.

Immunohistochemistry is performed as additional test. The strong positive expression of cytokeratin 19 was showed in primary SCTC, and negative in metastatic SCTC.

It is important to exclude a tumor which is directly extending into the ear canal from the parotid salivary gland, especially when dealing with an adenoid cystic or mucoepidermoid carcinoma. This can be eliminated by clinical or imaging studies. Otherwise, the histologic differential diagnosis includes a ceruminous adenoma (a benign ceruminous gland tumor) or a neuroendocrine adenoma of the middle ear (middle ear adenoma).

The detection of tumours specific to VHL disease is important in the disease's diagnosis. In individuals with a family history of VHL disease, one hemangioblastoma, pheochromocytoma or renal cell carcinoma may be sufficient to make a diagnosis. As all the tumours associated with VHL disease can be found sporadically, at least two tumours must be identified to diagnose VHL disease in a person without a family history.

Genetic diagnosis is also useful in VHL disease diagnosis. In hereditary VHL, disease techniques such as southern blotting and gene sequencing can be used to analyse DNA and identify mutations. These tests can be used to screen family members of those afflicted with VHL disease; "de novo" cases that produce genetic mosaicism are more difficult to detect because mutations are not found in the white blood cells that are used for genetic analysis.

Radiologically

- Odontogenic Myxoma

- Ameloblastoma

- Central Giant Cell Granuloma

- Adenomatoid odontogenic tumor

Histologically

- Orthokeratocyst

- Radicular cyst (particularly if the OKC is very inflamed)

- Unicystic ameloblastoma

The definitive diagnosis is by histologic analysis, i.e. and examination under the microscope.

Under the microscope, OKCs vaguely resemble keratinized squamous epithelium; however, they lack rete ridges and often have an artifactual separation from their basement membrane.

On a CT scan, The radiodensity of a keratocystic odontogenic tumour is about 30 Hounsfield units, which is about the same as ameloblastomas. Yet, ameloblastomas show more bone expansion and seldom show high density areas.

The long-term prognosis for patients with Stargardt disease is widely variable although the majority of people will progress to legal blindness.

Stargardt disease has no impact on general health and life expectancy is normal. Some patients, usually those with the late onset form, can maintain excellent visual acuities for extended periods, and are therefore able to perform tasks such as reading or driving.

Complete surgical excision is the treatment of choice, associated with an excellent long term clinical outcome.

As metanephric adenomas are considered benign, they can be left in place, i.e. no treatment is needed.

Macular telangiectasia type 1 must be differentiated from secondary telangiectasis caused by retinal vascular diseases such as retinal venous occlusions, diabetic retinopathy, radiation retinopathy, sickle cell maculopathy, inflammatory retinopathy/Irvine–Gass syndrome, ocular ischemic syndrome/carotid artery obstruction, hypertensive retinopathy, polycythemia vera retinopathy, and localized retinal capillary hemangioma. In addition, Macular telangiectasia type 1 should be clearly differentiated from dilated perifoveal capillaries with evidence of vitreous cellular infiltration secondary to acquired inflammatory disease or tapetoretinal dystrophy. Less commonly, macular telangiectasis has been described in association with fascioscapulohumeral muscular dystrophy, incontinentia pigmenti, and familial exudative vitreoretinopathy with posterior pole involvement.

Macular telangiectasia type 2 is commonly under-diagnosed. The findings may appear very similar to diabetic retinopathy, and many cases ave been incorrectly ascribed to diabetic retinopathy or age-related macular degeneration. Recognition of this condition can save an affected patient from unnecessarily undergoing extensive medical testing and/or treatment. MacTel should be considered in cases of mild paramacular dot and blot hemorrhages and in cases of macular and paramacular RPE hyperplasia where no other cause can be identified.

Diagnosis of AIR can be difficult due to the overlap of symptoms with other disorders. Examination of the fundus (inner surface of eye) can show no results or it can show narrowing of the blood vessels, abnormal colouration of the optic disc, and retinal atrophy. Fundus examination results are not indicative of autoimmune retinopathy but they are used to initiate the diagnostic process. An electroretinogram (eye test used to see abnormalities in the retina) is used to detect AIR. An abnormal electroretinogram (ERG) with respect to light and dark adaptations indicates AIR. The ERG also allows differentiation between cancer-associated retinopathy and melanoma-associated retinopathy. If the ERG shows cone responses, CAR can be prematurely diagnosed. If the ERG shows a significant decrease in b-wave amplitude, MAR can be prematurely diagnosed. To confirm, analysis for anti-retinal antibodies through Western blotting of serum collected from the patient is done.

Wide, radical, complete surgical excision is the treatment of choice, with free surgical margins to achieve the best outcome and lowest chance of recurrence. Radiation is only used for palliation. In general, there is a good prognosis, although approximately 50% of patients die from disease within 3–10 years of presentation.

An accurate diagnosis of retinitis pigmentosa relies on the documentation of the progressive loss photoreceptor cell function, confirmed by a combination of visual field and visual acuity tests, fundus and optical coherence imagery, and electroretinography (ERG),

Visual field and acuity tests measure and compare the size of the patient's field of vision and the clarity of their visual perception with the standard visual measurements associated with healthy 20/20 vision. Clinical diagnostic features indicative of retinitis pigmentosa include a substantially small and progressively decreasing visual area in the visual field test, and compromised levels of clarity measured during the visual acuity test. Additionally, optical tomography such as fundus and retinal (optical coherence) imagery provide further diagnostic tools when determining an RP diagnosis. Photographing the back of the dilated eye allows the confirmation of bone spicule accumulation in the fundus, which presents during the later stages of RP retinal degeneration. Combined with cross-sectional imagery of optical coherence tomography, which provides clues into photoreceptor thickness, retinal layer morphology, and retinal pigment epithelium physiology, fundus imagery can help determine the state of RP progression.

While visual field and acuity test results combined with retinal imagery support the diagnosis of retinitis pigmentosa, additional testing is necessary to confirm other pathological features of this disease. Electroretinography (ERG) confirms the RP diagnosis by evaluating functional aspects associated with photoreceptor degeneration, and can detect physiological abnormalities before the initial manifestation of symptoms. An electrode lens is applied to the eye as photoreceptor response to varying degrees of quick light pulses is measured. Patients exhibiting the retinitis pigmentosa phenotype would show decreased or delayed electrical response in the rod photoreceptors, as well as possibly compromised cone photoreceptor cell response.

The patient's family history is also considered when determining a diagnosis due to the genetic mode of inheritance of retinitis pigmentosa. At least 35 different genes or loci are known to cause "nonsyndromic RP" (RP that is not the result of another disease or part of a wider syndrome). Indications of the RP mutation type can be determine through DNA testing, which is available on a clinical basis for:

- (autosomal recessive, Bothnia type RP)

- (autosomal dominant, RP1)

- (autosomal dominant, RP4)

- (autosomal dominant, RP7)

- (autosomal dominant, RP13)

- (autosomal dominant, RP18)

- CRB1 (autosomal recessive, RP12)

- (autosomal recessive, RP19)

- (autosomal recessive, RP20)

For all other genes (e.g. DHDDS), molecular genetic testing is available on a research basis only.

RP can be inherited in an autosomal dominant, autosomal recessive, or X-linked manner. X-linked RP can be either recessive, affecting primarily only males, or dominant, affecting both males and females, although males are usually more mildly affected. Some digenic (controlled by two genes) and mitochondrial forms have also been described.

Genetic counseling depends on an accurate diagnosis, determination of the mode of inheritance in each family, and results of molecular genetic testing.

It is important to separate hiberoma from adult rhabdomyoma, a granular cell tumor and a true liposarcoma.

Retinal detachment can be examined by fundus photography or ophthalmoscopy. Fundus photography generally needs a considerably larger instrument than the ophthalmoscope, but has the advantage of availing the image to be examined by a specialist at another location and/or time, as well as providing photo documentation for future reference. Modern fundus photographs generally recreate considerably larger areas of the fundus than what can be seen at any one time with handheld ophthalmoscopes.

Ultrasound has diagnostic accuracy similar to that of examination by an ophthalmologist. The recent meta-analysis shows the diagnostic accuracy of emergency department (ED) ocular ultrasonography is high. The sensitivity and specificity ranged from 97% to 100% and 83% to 100%. The typical feature of retinal detachment when viewed on ultrasound is "flying angel sign". It shows the detached retina moving with a fixed point under the B mode, linear probe 10 MHz.

MTSCC can be a difficult diagnosis due to its morphologic heterogeneity. Several morphological variants have been described, as the ‘‘mucin-poor variants’’, showing a predominance of tubular or spindle cell components and only minimal pale mucinous background.

Focal papillations or papillary cores and foamy histiocytes can also be seen, creating confusion with type 1 papillary RCC. Helpful features for diagnosis are bland cytologic features and adjacent tubular and spindle cell components. Focal areas of clear cells and oncocytic cells can also be present.

Metanephric adenoma is diagnosed histologically. The tumours can be located at upper pole, lower pole and mid-hilar region of the kidney; they are well circumscribed but unencapsulated, tan pink, with possible cystic and hemorrhagic foci. They show a uniform architecture of closely packed acinar or tubular structures of mature and bland appearance with scanty interposed stroma. Cells are small with dark staining nuclei and inconspicuous nucleoli. Blastema is absent whereas calcospherites may be present. Glomeruloid figures are a striking finding, reminiscent of early fetal metenephric tissue. The lumen of the acini may contain otherwise epithelial infoldings or fibrillary material but it is quite often empty. Mitoses are conspicuously absent.

In the series reported by Jones "et al." tumour cells were reactive for Leu7 in 3 cases of 5, to vimentine in 4 of 6, to cytocheratin in 2 of 6, to epithelial membrane antigen in 1 of 6 cases and muscle specific antigen in 1 of 6.

Olgac "et al." found that intense and diffuse immunoreactivity for alpha-methylacyl-CoA racemase (AMACR) is useful in differentiating renal cell carcinoma from MA but a panel including AMACR, CK7 and CD57 is better in this differential diagnosis.

Differential diagnosis may be quite difficult indeed as exemplified by the three malignancies initially diagnosed as MA that later metastasized, in the report by Pins et al.

Although MacTel is uncommon, its prevalence is probably higher than most physicians believe. The early findings are subtle, so the diagnosis is likely often missed by optometrists and general ophthalmologists. MacTel was detected in 0.1% of subjects in the Beaver Dam study population over age 45 years, but this is probably an underestimate because identification was made based only on color photographs.

No major new biomicroscopic features of MacTel have been identified since the early work of Gass and colleagues.

The advent of optical coherence tomography (OCT) has allowed better characterization of the nature of the inner and outer lamellar cavities. Loss of central masking seen on autofluorescence studies, apparently due to loss of luteal pigment, is now recognized as probably the earliest and most sensitive and specific MacTel abnormality.

The key fundus findings in macular telangiectasia type 2 involve retinal crystalline—fine, refractile deposits in the superficial retinal layers—may be seen within the affected area.a focal area of diminished retinal transparency (i.e. "greying") and/or small retinal hemorrhages just temporal to the fovea. Dilated capillaries may also be noted within this area, and while this is often difficult to visualize ophthalmoscopically, the abnormal capillary pattern is readily identifiable with fluorescein angiography.

Areas of focal RPE hyperplasia, i.e.pigment plaques, often develop in the paramacular region as a response to these abnormal vessels. Other signs of macular telangiectasia type 2 include right angle venules, representing an unusual alteration of the vasculature in the paramacular area, with vessels taking an abrupt turn toward the macula as if being dragged.

Diagnosis of MacTel type 2 may be aided by the use of advanced imaging techniques such as fluorescein angiography, fundus autofluorescence, and OCT. These can help to identify the abnormal vessels, pigment plaques, retinal crystals, foveal atrophy and intraretinal cavities associated with this disorder.

Fluorescein angiography (FA) is helpful in identifying the anomalous vasculature, particularly in the early stages of Type 2 disease. Formerly, FA was essential in making a definitive diagnosis. However, the diagnosis can be established with less invasive imaging techniques such as OCT and fundus autofluorescence. Some clinicians argue that FA testing may be unnecessary when a diagnosis is apparent via less invasive means.

The natural history of macular telangiectasia suggests a slowly progressive disorder. A retrospective series of 20 patients over 10 to 21 years showed deterioration of vision in more than 84% of eyes, either due to intra-retinal edema and serous retinal detachment (Type 1) or pigmented RPE scar formation or neovascularisation (Type 2).

A diagnosis of choroideremia can be made based on family history, symptoms, and the characteristic appearance of the fundus. However, choroideremia shares several clinical features with retinitis pigmentosa, a similar but broader group of retinal degenerative diseases, making a specific diagnosis difficult without genetic testing. Because of this choroideremia is often initially misdiagnosed as retinitis pigmentosa. A variety of different genetic testing techniques can be used to make a differential diagnosis.

Chondromyxoid fibromas can share characteristics with chondroblastomas with regards to histologic and radiographic findings. However they more commonly originate from the metaphysis, lack calcification and have a different histologic organization pattern. Other differential diagnoses for chondroblastoma consist of giant cell tumors, bone cysts, eosinophilic granulomas, clear cell chondrosarcomas, and enchondromas (this list is not exhaustive).

Spermatocytic seminomas are diagnosed based on tissue from orchiectomy (or partial orchiectomy), done for a lesion suspicious for cancer on medical imaging.

The macroscopic appearance of the tumour is of a mutinodular grey-white to tan coloured mass with gelatinous, haemorrhagic and necrotic areas. The tumour may extend beyond the testis.

A minority of retinal detachments result from trauma, including blunt blows to the orbit, penetrating trauma, and concussions to the head. A retrospective Indian study of more than 500 cases of rhegmatogenous detachments found that 11% were due to trauma, and that gradual onset was the norm, with over 50% presenting more than one month after the inciting injury.

STGD1 is the most common form of inherited juvenile macular degeneration with a prevalence of approximately 1 in 10,000 births.

This type of carcinoma is commonly managed by local resection, cryotherapy, topical chemotherapy, and radiotherapy. Multimodal therapy has been shown to improve both visual prognosis and survival.

Mohs micrographic surgery has become the treatment of choice for this form of cancer. When used as the primary treatment modality for sebaceous carcinoma of the eyelid, Mohs surgery is associated with significantly lower local and distant recurrence rates.

Despite the temporary nature of the vision loss, those experiencing amaurosis fugax are usually advised to consult a physician immediately as it is a symptom that may herald serious vascular events, including stroke. Restated, “because of the brief interval between the transient event and a stroke or blindness from temporal arteritis, the workup for transient monocular blindness should be undertaken without delay.” If the patient has no history of giant cell arteritis, the probability of vision preservation is high; however, the chance of a stroke reaches that for a hemispheric TIA. Therefore, investigation of cardiac disease is justified.

A diagnostic evaluation should begin with the patient's history, followed by a physical exam, with particular importance being paid to the ophthalmic examination with regards to signs of ocular ischemia. When investigating amaurosis fugax, an ophthalmologic consult is absolutely warranted if available. Several concomitant laboratory tests should also be ordered to investigate some of the more common, systemic causes listed above, including a complete blood count, erythrocyte sedimentation rate, lipid panel, and blood glucose level. If a particular cause is suspected based on the history and physical, additional relevant labs should be ordered.

If laboratory tests are abnormal, a systemic disease process is likely, and, if the ophthalmologic examination is abnormal, ocular disease is likely. However, in the event that both of these routes of investigation yield normal findings or an inadequate explanation, noninvasive duplex ultrasound studies are recommended to identify carotid artery disease. Most episodes of amaurosis fugax are the result of stenosis of the ipsilateral carotid artery. With that being the case, researchers investigated how best to evaluate these episodes of vision loss, and concluded that for patients ranging from 36–74 years old, "...carotid artery duplex scanning should be performed...as this investigation is more likely to provide useful information than an extensive cardiac screening (ECG, Holter 24-hour monitoring, and precordial echocardiography)." Additionally, concomitant head CT or MRI imaging is also recommended to investigate the presence of a “clinically silent cerebral embolism.”

If the results of the ultrasound and intracranial imaging are normal, “renewed diagnostic efforts may be made,” during which fluorescein angiography is an appropriate consideration. However, carotid angiography is not advisable in the presence of a normal ultrasound and CT.